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NASA Technical Reports Server (NTRS)
Kinzler, J. A.; Hefferman, J. T.; Fehrenkamp, L. G.; Lee, W. S. (Inventor)
A surface of an article adapted for relative motion with a fluid environment is finished by coating the surface with a fluid adhesive, covering the adhesive with a sheet of flexible film material under tension on the film material whereby the tensioned film material is bonded to the surface by the adhesive.
Surface Finishing for Biomaterials
NASA Astrophysics Data System (ADS)
Mizutani, Masayoshi; Komotori, Jun; Nagata, Jin; Katahira, Kazutoshi; Ohmori, Hitoshi
Conventional biomaterials, such as titanium alloys, require enhanced chemical stability and wear resistance, which are dependent on the quality of the surficial oxide layer. However, it is very difficult to produce a sufficiently homogenous oxide layer by polishing using isolation abrasive alone. In our previous study, we proposed a new electrical grinding method (ELID grinding). The process improves oxide formation on the finished surface, resulting in finished surfaces with very thick and potentially stable oxide layers. In this study, to ensure the fabrication of surface with desirable characteristics for biomaterials, three types of specimens, which were processed with different surface finishing methods were prepared. Processed surfaces were analyzed by using an Energy Dispersive X-ray analyzer (EDX). To measure the thickness of surface oxide layers, detailed observation were performed by using a Transmission Electron Microscope (TEM). Although the ELID ground surface shows a higher value of surface roughness, excellent corrosion resistance was observed as compared with the samples finished by polishing. This is because of the formation of a thick oxide layer on the finished surface by ELID grinding. Consequently, ELID grinding appears to offer significant future promise for use in biomaterials and other engineering components subjected to the corrosion process.
Surface finishing. [for aircraft wings
NASA Technical Reports Server (NTRS)
Kinzler, J. A.; Heffernan, J. T.; Fehrenkamp, L. G.; Lee, W. S. (Inventor)
A surface of an article adapted for relative motion with a fluid environment is finished by coating the surface with a fluid adhesive. The adhesive is covered with a sheet of flexible film material under tension, and the adhesive is set while maintaining tension on the film material.
Surface Finish after Laser Metal Deposition
NASA Astrophysics Data System (ADS)
Rombouts, M.; Maes, G.; Hendrix, W.; Delarbre, E.; Motmans, F.
Laser metal deposition (LMD) is an additive manufacturing technology for the fabrication of metal parts through layerwise deposition and laser induced melting of metal powder. The poor surface finish presents a major limitation in LMD. This study focuses on the effects of surface inclination angle and strategies to improve the surface finish of LMD components. A substantial improvement in surface quality of both the side and top surfaces has been obtained by laser remelting after powder deposition.
NCMS PWB Surface Finishes Team project summary
Kokas, J.; DeSantis, C.; Wenger, G.
The NCMS PWB Surface Finishes Consortium is just about at the end of the five year program. Dozens of projects related to surface finishes and PWB solder-ability were performed by the team throughout the program, and many of them are listed in this paper. They are listed with a cross reference to where and when a technical paper was presented describing the results of the research. However, due to time and space constraints, this paper can summarize the details of only three of the major research projects accomplished by the team. The first project described is an ``Evaluation of PWB Surface Finishes.`` It describes the solderability, reliability, and wire bondability of numerous surface finishes. The second project outlined is an ``Evaluation of PWB Solderability Test Methods.`` The third project outlined is the ``Development and Evaluation of Organic Solderability Preservatives.``
Optimizing parameters for magnetorheological finishing supersmooth surface
NASA Astrophysics Data System (ADS)
Cheng, Haobo; Feng, Zhijing; Wang, Yingwei
This paper presents a reasonable approach to this issue, i.e., computer controlled magnetorheological finishing (MRF). In MRF, magnetically stiffened magnetorheological (MR) abrasive fluid flows through a preset converging gap that is formed by a workpiece surface and a moving rigid wall, to create precise material removal and polishing. Tsinghua University recently completed a project with MRF technology, in which a 66 mm diameter, f/5 parabolic mirror was polished to the shape accuracy of λ/17 RMS (λ=632.8nm) and the surface roughness of 1.22 nm Ra. This was done on a home made novel aspheric computer controlled manufacturing system. It is a three-axis, self-rotating wheel machine, the polishing tool is driven with one motor through a belt. This paper presents the manufacturing and testing processes, including establish the mathematics model of MRF optics on the basis of Preston equation, profiler test and relative coefficients, i.e., pressure between workpiece and tool, velocity of MR fluid in polishing spot, tolerance control of geometrical parameters such as radius of curvature and conic constant also been analyzed in the paper. Experiments were carried out on the features of MRF. The results indicated that the required convergent speed, surface roughness could be achieved with high efficiency.
Effect of Burnishing Parameters on Surface Finish
NASA Astrophysics Data System (ADS)
Shirsat, Uddhav; Ahuja, Basant; Dhuttargaon, Mukund
Burnishing is cold working process in which hard balls are pressed against the surface, resulting in improved surface finish. The surface gets compressed and then plasticized. This is a highly finishing process which is becoming more popular. Surface quality of the product improves its aesthetic appearance. The product made up of aluminum material is subjected to burnishing process during which kerosene is used as a lubricant. In this study factors affecting burnishing process such as burnishing force, speed, feed, work piece diameter and ball diameter are considered as input parameters while surface finish is considered as an output parameter In this study, experiments are designed using 25 factorial design in order to analyze the relationship between input and output parameters. The ANOVA technique and F-test are used for further analysis.
This document provides guidance to surface finishing manufacturers on control technologies and process changes for approaching zero discharge (AZD). AZD is a key theme underlying the Strategic Goals Program (SGP). The SGP is a cooperative effort between the EPA nd the American El...
Lathe Attachment Finishes Inner Surface of Tubes
NASA Technical Reports Server (NTRS)
Lancki, A. J.
Extremely smooth finishes are machined on inside surfaces of tubes by new attachment for a lathe. The relatively inexpensive accessory, called a "microhone," holds a honing stone against workpiece by rigid tangs instead of springs as in conventional honing tools. Inner rod permits adjustment of microhoning stone, while outer tube supports assembly. Outer tube is held between split blocks on lathe toolpost. Microhoning can be done with either microhone or workpiece moving and other member stationary.
Densified carbonaceous bodies with improved surface finishes
Hucke, E.E.
A method is described of producing a densified carbonaceous body with a superior surface finish, the method comprising the steps of: impregnating a permeable body composed essentially of a fine grained, isotropic graphite with a liquid impregnant containing furfural or furfural alcohol or a mixture thereof, an acid catalyst, and a pore-forming agent comprising a polyalkylene oxide adduct nonionic surfactant; heating the impregnated, permeable body to a temperature which is sufficiently high to polymerize the impregnant; and then heating the body to a temperature which is sufficiently high to pyrolyze the carbon in the polymerized impregnant.
Review of Capabilities of the ENEPIG Surface Finish
NASA Astrophysics Data System (ADS)
Ratzker, Menahem; Pearl, Adam; Osterman, Michael; Pecht, Michael; Milad, George
Surface finishes are used to protect exposed copper metallization in printed circuit boards from oxidation and to provide a solderable surface on which to mount electronic components. While it is true that some people have called electroless nickel electroless palladium immersion gold (ENEPIG) a "universal finish" for a wide range of applications from wire bonding to solder interconnects, this paper provides a review of the current literature on ENEPIG and assesses its overall capabilities compared to other surface finishes. Gaps in understanding the performance of ENEPIG as a printed wiring board surface finish are identified and further testing is recommended.
30 CFR 18.33 - Finish of surface joints.
Code of Federal Regulations, 2012 CFR
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Finish of surface joints. 18.33 Section 18.33 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND... Requirements § 18.33 Finish of surface joints. Flat surfaces between bolt holes that form any part of a...
30 CFR 18.33 - Finish of surface joints.
Code of Federal Regulations, 2011 CFR
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Finish of surface joints. 18.33 Section 18.33 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND... Requirements § 18.33 Finish of surface joints. Flat surfaces between bolt holes that form any part of a...
30 CFR 18.33 - Finish of surface joints.
Code of Federal Regulations, 2013 CFR
... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Finish of surface joints. 18.33 Section 18.33 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND... Requirements § 18.33 Finish of surface joints. Flat surfaces between bolt holes that form any part of a...
30 CFR 18.33 - Finish of surface joints.
Code of Federal Regulations, 2014 CFR
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Finish of surface joints. 18.33 Section 18.33 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND... Requirements § 18.33 Finish of surface joints. Flat surfaces between bolt holes that form any part of a...
30 CFR 18.33 - Finish of surface joints.
Code of Federal Regulations, 2010 CFR
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Finish of surface joints. 18.33 Section 18.33 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES Construction and Design Requirements § 18.33 Finish of...
Large planer for finishing smooth, flat surfaces of large pieces ...
Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey
Large planer for finishing smooth, flat surfaces of large pieces of metal; in operating condition and used for public demonstrations. - Thomas A. Edison Laboratories, Building No. 5, Main Street & Lakeside Avenue, West Orange, Essex County, NJ
Solder flow over fine line PWB surface finishes
Hosking, F.M.; Hernandez, C.L.
The rapid advancement of interconnect technology has stimulated the development of alternative printed wiring board (PWB) surface finishes to enhance the solderability of standard copper and solder-coated surfaces. These new finishes are based on either metallic or organic chemistries. As part of an ongoing solderability study, Sandia National Laboratories has investigated the solder flow behavior of two azole-based organic solderability preservations, immersion Au, immersion Ag, electroless Pd, and electroless Pd/Ni on fine line copper features. The coated substrates were solder tested in the as-fabricated and environmentally-stressed conditions. Samples were processed through an inerted reflow machine. The azole-based coatings generally provided the most effective protection after aging. Thin Pd over Cu yielded the best wetting results of the metallic coatings, with complete dissolution of the Pd overcoat and wetting of the underlying Cu by the flowing solder. Limited wetting was measured on the thicker Pd and Pd over Ni finishes, which were not completely dissolved by the molten solder. The immersion Au and Ag finishes yielded the lowest wetted lengths, respectively. These general differences in solderability were directly attributed to the type of surface finish which the solder came in contact with. The effects of circuit geometry, surface finish, stressing, and solder processing conditions are discussed.
Analytical methods for the characterization of surface finishing in bricks.
Nardini, I; Zendri, E; Biscontin, G; Brunetin, A
The recent restoration works of Santo Stefano Church Façade (XV century) in Venice have shown traces variously saved of different kind of surface finishes. These finishes were found on the brick's surface both in the masonry and in the decorative elements. Different brick's surface and decorative tile samples were investigated using several techniques: optical microscopy, scanning electron-microscopy, thermal analysis, infrared spectroscopy and reflectance Fourier transform infrared microspectroscopy. The evaluation of the reached results was used to understand the decorative techniques and to recognize the material employed. PMID:17723684
Reflective fiber optic probe for surface finish survey
NASA Astrophysics Data System (ADS)
Wawrzyniuk, Leszek
The Report relates to verification of the design of refractive fiber optic probes designed for checking surface finish condition and provides a description of tests on the models of such probes. Presented in the paper are the results of performance tests of a bifurcated probe to the concept of application of a non-random bundle of light guides for identification of surfaces representing different CLA values (0.32, 0.63, 1.25, 2.50 micrometers).
Corrective finishing of a micro-aspheric mold made of tungsten carbide to 50 nm accuracy.
Guo, Jiang
The increasing demand on the optical performance of micro-aspheric glass lenses used for consumer, medical, as well as industrial applications places a high requirement on the surface quality of the molds used for replicating these lenses. However, it is difficult, almost impossible to generate a supersmooth surface with extremely high form accuracy by using the current cutting or grinding techniques. Therefore, this paper presents a corrective polishing process to finish micro-aspheric molds made of tungsten carbide by applying the vibration-assisted polishing method, aiming to obtain tens-of-nanometer form accuracy and subnanometer surface roughness. A polishing system which provides precise position, angle, and force control in 5 degrees of freedom (DOF)is employed for the experiments, and a tilting angle control method is introduced for the ease of the precisely controlling polishing force so as to keep the material removal rate stable. Then a dwell time algorithm is proposed by considering the scanning path of the polishing tool and the tilting angle of the workpiece. The experimental results show that after corrective polishing, the form accuracy of a micro-aspheric mold with high numerical aperture (NA) is successfully improved from 230 nm peak-to-valley (PV) to under 50 nm PV, while the surface roughness is reduced from 7.2 nm root-mean-square (rms) to 0.5 nm rms. PMID:26193027
Improvement of figure and finish of diamond turned surfaces with magneto-rheological finishing (MRF)
NASA Astrophysics Data System (ADS)
Dumas, Paul; Golini, Don; Tricard, Marc
Single Point Diamond Turning (SPDT) has been a cost effective technique to achieve the required figure and roughness specification on a wide range of infrared (IR) optics. SPDT is one of the few technologies that can efficiently generate aspherical surfaces, and as recent developments such as fast-tool servos mature, "free-form" surfaces are becoming feasible as well. Optical end-user requirements for a wide range of industries are continuing to tighten, driven, for example by multi-spectral systems that require good performance at shorter wavelengths in addition to IR. In many cases, specified shape tolerances can exceed SPDT capabilities. Additionally, SPDT typically leaves "turning marks" (affecting micro-roughness) that can be detrimental to performance. In some cases, surface integrity (e.g. sub-surface damage) can also be of concern. Magneto-Rheological Finishing (MRF®) has the proven ability to simultaneously improve roughness, figure, and surface integrity in a fast and cost effective manner. MRF is a deterministic, sub-aperture polishing technology, and is typically employed as the last manufacturing step. MRF can deterministically remove from tens of nanometers to microns worth of material, while efficiently "converging" to the specified requirements. Conversely, SPDT has proven to be very effective in removing the hundreds of microns (if not mm) sometimes required to "pre-shape" an aspheric surface before its final polish. After a brief introduction of MRF, this paper will discuss how SPDT and MRF processes can complement one another very effectively. Examples of MRF results on a wide range of IR materials will be presented.
Polymer micromolds with near optical quality surface finishes
NASA Astrophysics Data System (ADS)
Shiu, Pun-Pang; Knopf, George K.; Nikumb, Suwas
Disposable microfluidic systems are used to avoid sample contamination in a variety of medical and environmental monitoring applications. A contactless hot intrusion (HI) process for fabricating reusable polymer micromolds with near "optical quality" surface finishes is described in this paper. A metallic hot intrusion mask with the desired microchannels and related passive components is first machined using a tightly focused beam from a diode-pumped solid-state (DPSS) laser. The polymer mold master is then created by pressing the 2D metallic mask onto a polymethylmethacrylate (PMMA) substrate. Since it is a contactless fabrication process the resultant 3D micro-reliefs have near optical quality surface finishes. Unfortunately, the desired micro-relief dimensions (height and width) are not easily related to the hot intrusion process parameters of pressure, temperature, and time exposure profile. A finite element model is introduced to assist the manufacturing engineer in predicting the behavior of the PMMA substrate material as it deforms under heat and pressure during micromold manufacture. The FEM model assumes that thermo-plastics like PMMA become "rubber like" when heated to a temperature slightly above the glass transition temperature. By controlling the material temperature and maintaining its malleable state, it is possible to use the stress-strain relationship to predict the profile dimensions of the imprinted microfeature. Examples of curved microchannels fabricated using PMMA mold masters are presented to illustrate the proposed methodology and verify the finite element model. In addition, the non-contact formation of the micro-reliefs simplifies the demolding process and helps to preserve the high quality surface finishes.
Adaptive control of surface finish in automated turning processes
NASA Astrophysics Data System (ADS)
García-Plaza, E.; Núñez, P. J.; Martín, A. R.; Sanz, A.
The primary aim of this study was to design and develop an on-line control system of finished surfaces in automated machining process by CNC turning. The control system consisted of two basic phases: during the first phase, surface roughness was monitored through cutting force signals; the second phase involved a closed-loop adaptive control system based on data obtained during the monitoring of the cutting process. The system ensures that surfaces roughness is maintained at optimum values by adjusting the feed rate through communication with the PLC of the CNC machine. A monitoring and adaptive control system has been developed that enables the real-time monitoring of surface roughness during CNC turning operations. The system detects and prevents faults in automated turning processes, and applies corrective measures during the cutting process that raise quality and reliability reducing the need for quality control.
Influence of Finishing/Polishing Procedures on the Surface Texture of Two Resin Composites
Kameyama, Atsushi; Nakazawa, Taeko; Haruyama, Akiko; Haruyama, Chikahiro; Hosaka, Makoto; Hirai, Yoshito
This study compared surface roughness and gloss produced by different finishing/polishing procedures for two resin composites, Clearfil AP-X (AP-X) and Estelite Σ (ES). A total of 70 composite discs (n=35 for each resin composite) were prepared and divided at random into seven finishing/polishing groups (n=5): glass-pressed control; using a super-fine-grit diamond bur (SF); using CompoMaster (CM) after SF-finishing (SF+CM); using White Point (WP) after SF-finishing (SF+WP); using CM after SF+WP-finishing (SF+WP+CM); using Stainbuster (SB) after SF-finishing (SF+SB); and using CM after SF+SB-finishing (SF+SB+CM). After the finishing/polishing procedures, average surface roughness (Ra) and surface gloss (Gs(60°)) of all specimens were assessed with a surface profilometer and specimen gloss meter, respectively. Glass-pressed controls for both AP-X and ES composites showed the best surface finish in terms of both Ra and Gs(60°). SF-finishing produced the roughest surface and led to almost complete loss of gloss. While additional polishing with CM reduced Ra and increased Gs(60°), the additional finishing effect of WP or SB between SF-finishing and CM-polishing was not found for either AP-X or ES. PMID:19088883
Specification And Control Of Surface Finish: Empiricism Versus Dogmatism
NASA Astrophysics Data System (ADS)
Stout, K. J.; Obray, C.; Jungles, J.
This paper reviews the development of the analysis of surface finish from the early attempts in the 1930s to the present day. The development of parameters used in surface analysis is shown in context with the instrumental techniques available at the time, and it is argued that characterization based on graphical and experimental convenience has influenced industrial practice. As the requirements of manufacture and functional performance have been stretched by advancing technology, many industrialists have been forced to accept the fact that existing specification practices are limited and have sought alternative descriptions based on well-established techniques; but these techniques themselves are limited, their suitability to in-process measurement being practically nonexistent. It is shown that attempts have been made recently to develop optical methods of assessing surface finish using traditional parameters such as Ra. This paper suggests that it may be time to look toward a new form of specification that is more suited to assessment by optical transducers, and some methods of assessment are proposed. To support this view, a simple low-cost device is discussed that can be calibrated to give Ra but that also presents information in a more relevant empirical way that may be more valid than the existing parameter specification.
Influence of finishing by burnishing on surface characteristics
NASA Astrophysics Data System (ADS)
Saï, W. Bouzid; Lebrun, J. L.
The aim of this study was to analyze the evolution of residual stresses, microhardness, and roughness in relation to the finishing process. The x-ray diffraction (XRD) technique was used to determine the residual stresses, which were measured from the surface to the bottom of the machined workpiece. Processes that were studied included turning, grinding, and burnishing. Burnishing was done on a surface that was initially turned, or turned and then ground. A duplex stainless steel was used in this study. This material belongs to a high-strength stainless steel family with high corrosion resistance properties. We noted that the burnishing process produces the best quality of the surface when compared with turning or grinding.
Deburring and surface finishing: The past ten years and projections for the next ten years
Gillespie, L.K.
The 1970s were a decade of significant growth in deburring and surface finishing. In the 1980s progress was made in robotic finishing, burr formation models, surface finish measurement, new processes, equipment and tooling. The centers of burr and surface related research changed. The decade of the 1990s will bring greater competition, environmental restrictions, more processes, more automation, and better characterization and simulation of processes.
Towards Arbitrary Accuracy Inviscid Surface Boundary Conditions
NASA Technical Reports Server (NTRS)
Dyson, Rodger W.; Hixon, Ray
Inviscid nonlinear surface boundary conditions are currently limited to third order accuracy in time for non-moving surfaces and actually reduce to first order in time when the surfaces move. For steady-state calculations it may be possible to achieve higher accuracy in space, but high accuracy in time is required for efficient simulation of multiscale unsteady phenomena. A surprisingly simple technique is shown here that can be used to correct the normal pressure derivatives of the flow at a surface on a Cartesian grid so that arbitrarily high order time accuracy is achieved in idealized cases. This work demonstrates that nonlinear high order time accuracy at a solid surface is possible and desirable, but it also shows that the current practice of only correcting the pressure is inadequate.
Computer Simulation Of An In-Process Surface Finish Sensor.
NASA Astrophysics Data System (ADS)
Rakels, Jan H.
It is generally accepted, that optical methods are the most promising for the in-process measurement of surface finish. These methods have the advantages of being non-contacting and fast data acquisition. Furthermore, these optical instruments can be easily retrofitted on existing machine-tools. In the Micro-Engineering Centre at the University of Warwick, an optical sensor has been developed which can measure the rms roughness, slope and wavelength of turned and precision ground surfaces during machining. The operation of this device is based upon the Kirchhoff-Fresnel diffraction integral. Application of this theory to ideal turned and ground surfaces is straightforward, and indeed the calculated diffraction patterns are in close agreement with patterns produced by an actual optical instrument. Since it is mathematically difficult to introduce real machine-tool behaviour into the diffraction integral, a computer program has been devised, which simulates the operation of the optical sensor. The program produces a diffraction pattern as a graphical output. Comparison between computer generated and actual diffraction patterns of the same surfaces show a high correlation. The main aim of this program is to construct an atlas, which maps known machine-tool errors versus optical diffraction patterns. This atlas can then be used for machine-tool condition diagnostics. It has been found that optical monitoring is very sensitive to minor defects. Therefore machine-tool detoriation can be detected before it is detrimental.
The accuracy of altimetric surfaces
NASA Technical Reports Server (NTRS)
Wunsch, C.; Zlotnicki, V.
Estimates of the shape of the sea surface as determined from satellite altimeters have become of increasing importance in geophysics, geodesy and physical oceanography. The most effective error reduction procedures used in producing these surfaces have been some version of a crossing-arc analysis. The problem with this procedure is the absence of an easy means of evaluating the noise structure of the final result. By recasting the problem as one of objective mapping (optimal estimation) the error reduction is optimized and an explicit estimate is obtained of the wave-number structure of the final altimetric surface. Examples, suitable to a small computer, have been generated to show that the error reduction along the sub-satellite tracks is very great, with most of the residual lying in long wavelengths.
The topographic development and areal parametric characterization of a stratified surface polished by mass finishing
NASA Astrophysics Data System (ADS)
Walton, Karl; Blunt, Liam; Fleming, Leigh
Mass finishing is amongst the most widely used finishing processes in modern manufacturing, in applications from deburring to edge radiusing and polishing. Processing objectives are varied, ranging from the cosmetic to the functionally critical. One such critical application is the hydraulically smooth polishing of aero engine component gas-washed surfaces. In this, and many other applications the drive to improve process control and finish tolerance is ever present. Considering its widespread use mass finishing has seen limited research activity, particularly with respect to surface characterization. The objectives of the current paper are to; characterise the mass finished stratified surface and its development process using areal surface parameters, provide guidance on the optimal parameters and sampling method to characterise this surface type for a given application, and detail the spatial variation in surface topography due to coupon edge shadowing. Blasted and peened square plate coupons in titanium alloy are wet (vibro) mass finished iteratively with increasing duration. Measurement fields are precisely relocated between iterations by fixturing and an image superimposition alignment technique. Surface topography development is detailed with 'log of process duration' plots of the 'areal parameters for scale-limited stratified functional surfaces', (the Sk family). Characteristic features of the Smr2 plot are seen to map out the processing of peak, core and dale regions in turn. These surface process regions also become apparent in the 'log of process duration' plot for Sq, where lower core and dale regions are well modelled by logarithmic functions. Surface finish (Ra or Sa) with mass finishing duration is currently predicted with an exponential model. This model is shown to be limited for the current surface type at a critical range of surface finishes. Statistical analysis provides a group of areal parameters including; Vvc, Sq, and Sdq
An ultra-low surface finish process for 6061-Al mirrors
NASA Astrophysics Data System (ADS)
Wamboldt, Leonard; Roy, Brian; Crifasi, Joseph; Stephens, Shane; Hanninen, Derek; Woodard, Kenneth; Felock, Robert; Cunha-Vasconcelos, Sofia; Polczwartek, Stephen; Parenteau, Jeffrey
An ultra-low surface finishing process for 6061 T6 type aluminum has been developed by Corning Incorporated, Specialty Materials Division, and has been successfully applied to mirrors up to 13 inches in diameter. This paper presents finish and figure data achieved from the mirror finishing process. Mirror stability is demonstrated through Pre and post thermal cycle surface figure measurements; temperature range of cycle -55°C to +70°C. As an added benefit, the process enables the use of deterministic finishing and enhances the reflective optics resistance to corrosion. Survivability of the reflective optic is evaluated through extended humidity testing.
Surface Fatigue Lives of Case-Carburized Gears With an Improved Surface Finish
NASA Technical Reports Server (NTRS)
Krantz, T. L.; Alanou, M. P.; Evans, H. P.; Snidle, R. W.; Krantz, T. L. (Technical Monitor)
Previous research provides qualitative evidence that an improved surface finish can increase the surface fatigue lives of gears. To quantify the influence of surface roughness on life, a set of AISI 93 10 steel gears was provided with a nearmirror finish by superfinishing. The effects of the superfinishing on the quality of the gear tooth surfaces were determined using data from metrology, profilometry, and interferometric microscope inspections. The superfinishing reduced the roughness average by about a factor of 5. The superfinished gears were subjected to surface fatigue testing at 1.71 -GPa (248-ksi) Hertz contact stress, and the data were compared with the NASA Glenn gear fatigue data base. The lives of gears with superfinished teeth were about four times greater compared with the lives of gears with ground teeth but with otherwise similar quality.
Nanometric Finishing on Biomedical Implants by Abrasive Flow Finishing
NASA Astrophysics Data System (ADS)
Subramanian, Kavithaa Thirumalai; Balashanmugam, Natchimuthu; Shashi Kumar, Panaghra Veeraiah
Abrasive flow finishing (AFF) is a non-conventional finishing technique that offers better accuracy, efficiency, consistency, economy in finishing of complex/difficult to machine materials/components and provides the possibility of effective automation as aspired by the manufacturing sector. The present study describes the finishing of a hip joint made of ASTM grade Co-Cr alloy by Abrasive Flow Machining (AFM) process. The major input parameters of the AFF process were optimized for achieving nanometric finishing of the component. The roughness average (Ra) values were recorded during experimentation using surface roughness tester and the results are discussed in detail. The surface finished hip joints were characterized using Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM) and residual stress analysis using X-Ray Diffraction (XRD). The discussion lays emphasis on the significance, efficacy and versatile nature of the AFF process in finishing of bio-medical implants.
Laser engineered net shaping (LENS{trademark}) process: Optimization of surface finish and microstructural properties
Smugeresky, J.E.; Keicher, D.M.; Romero, J.A.; Griffith, M.L.; Harwell, L.D.
Rapid prototyping (RP) has revolutionized the approach to fabricating geometrically complex hardware from a CAD solid model. The various RP techniques allow component designers to directly fabricate conceptual models in plastics and polymer coated metals; however, each of the techniques requires additional processes, e.g. investment casting, to allow the fabrication of functional metallic hardware. This limitation has provided the impetus for further development of solid freeform fabrication technologies which enable fabrication of functional metallic hardware directly from the CAD solid model. The Laser Engineered Net Shaping (LENS{trademark}) process holds promise in satisfying this need. This newly emerging technology possesses the capability to fabricate fully dense components with good dimensional accuracy and with unique materials properties. Relatively complex geometrical shapes have been fabricated using this technology. In continuing to develop the LENS{trademark} process, further advancements are required. The functional dependence of the component surface finish and microstructural characteristics on process parameters including power size and size distribution are being evaluated. A set of statistically designed experiments is being used to sort through the various process parameters and identify significant process variables for improving surface finish and achieving optimum material microstructural properties.
Hydrophilic modification of polyester fabric by applying nanocrystalline cellulose containing surface finish.
Zaman, Masuduz; Liu, Hongbin; Xiao, Huning; Chibante, Felipe; Ni, Yonghao
In this study, polyethylene terephthalate (PET) fabric was modified by applying a hydrophilic surface finishing agent that contains nanocrystalline cellulose (NCC). To impart superior hydrophilicity, NCC was further cationically modified through quaternization by grafting glycidyl tri-methyl ammonium chloride (GTMAC). A textile binder, PrintRite595(®), was added to the finishing system. The surface finish was applied on the fabric using a rolling-drying-curing process. The modified fabric was characterized in terms of coating durability, moisture regain, and wettability. The durability of the surface finish was tested by six repeated washing steps. The surface properties of the fabric changed from hydrophobic to hydrophilic after heat treatment with the NCC-containing surface finishing agent. The results from the washing fastness, SEM, FTIR, and EDX analyses confirmed that the cationic NCC-containing textile surface finish showed superior adhesion onto the cationic dyeable (anionic) PET surface over the un-modified NCC. Furthermore, the cationic textile surface finish was capable of withstanding multiple washing cycles. PMID:23121945
77 FR 12227 - Long Term 2 Enhanced Surface Water Treatment Rule: Uncovered Finished Water Reservoirs; Public...
Federal Register 2010, 2011, 2012, 2013, 2014
... AGENCY 40 CFR Parts 141 and 142 Long Term 2 Enhanced Surface Water Treatment Rule: Uncovered Finished Water Reservoirs; Public Meeting AGENCY: Environmental Protection Agency (EPA). ACTION: Notice of public..., concerning information that may inform the regulatory review of the uncovered finished water...
Analysis of the influence of electrolyte on surface finish in electropolished stainless steel
NASA Astrophysics Data System (ADS)
Hernando, M.; Núñez, P. J.; García, E.; Trujillo, R.
Electropolishing is a surface finishing process of metals and alloys that enhances brilliant surface finishes with low surface roughness values. The most widely used electrolytes for the electropolishing of stainless steel are varying concentrations of phosphoric and sulphuric acid, and occasionally additives such as chromic acid. The objective of this study was to assess the performance of three commonly used industrial electrolytes in terms of the surface finish of electropolished stainless steel AISI 316L. Each electrolyte had varying sulphuric-phosphoric acid combinations with or without chromic acid. The following electropolishing conditions were assessed: current density, bath temperature, electropolishing time, and initial surface texture. The results revealed that adding chromic acid to the electrolyte did not significantly enhance surface finish, and electropolishing ranges were quite similar for all three electrolytes.
Effect of interior surface finish on the break-up of commercial shaped charge liners
Baker, E L; Schwartz, A J
A series of experiments aimed at understanding the influence of the liner interior surface finish on the break-up of shaped charge jets has been completed. The experiments used a standard 81-mm shaped charge design, loaded with LX-14 high explosive; incorporating high-precision copper shaped charged liners. The results indicate that a significant reduction of jet break-up time occurs between a surface finish of 99.30 microinches and 375.65 microinches. Surface finishes of 4.78, 44.54 and 99.30 microinches produced significantly better ductility and associated break-up times than the 375.65-microinch finish. The baseline production process high-precision liners were measured to have an average surface finish of 44.54 microinches. The results show that for the shaped charge warhead geometry and explosive combination investigated, some care must be taken in respect to surface finish, but that very fine surface finishes do not significantly improve the jet ductility and associated break-up times.
Minimum 10-year Survival of Kerboull Cemented Stems According to Surface Finish
Baqué, François; Lefevre, Nicolas; Kerboull, Marcel
The optimal surface finish for a cemented THA stem is still debated. We hypothesized surface finish would influence survival of Kerboull cemented hip arthroplasties and a matte finish would have lower survival. We reviewed survival of 433 total hip arthroplasties in 395 patients: 284 consecutive patients (310 hips) were enrolled in a prospective, randomized study of polished (165 hips) or matte finish stems (145 hips) and compared to a historical series of satin stems (123 hips) in 111 patients. The satin and matte finish implants had similar geometry but the polished was quadrangular rather than oval. Finish roughnesses were: polished (radius, 0.04 μm), satin (radius, 0.9 μm), and matte (radius, 1.7 μm). The mean age of the patients at the time of the index arthroplasty was 63.6 years. The survival rate at 13 years, using radiographic loosening as the end point, was 97.3% ± 2.6% for polished stems, 97.1% ± 2.1% for satin stems, and 78.9% ± 5.8% for matte stems. The data suggest survival of Kerboull stems was higher with a polished or satin surface finish than with a matte finish. Level of Evidence: Level II, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence. PMID:18196414
An experimental investigation on the influence of machining parameters on surface finish in diamond turning of silicon optics
NASA Astrophysics Data System (ADS)
Khatri, Neha; Sharma, Rohit; Mishra, Vinod; Kumar, Mukesh; Karar, Vinod; Sarepaka, RamaGopal V.
Silicon is widely used in IR optics, X-Ray optics and electronics applications. These applications require Silicon of optical quality surface as well as good form accuracy. To get the desired finish and dimensional accuracy, diamond turning is preferable. Taylor-Hobson Nanoform-250 diamond turning equipment is used to machine flat Silicon mirror. Negative rake diamond tool is used with a tool nose radius of 1.5 mm. A series of SPDT machining operations are performed in the sequential combinations of tool feed rate, Spindle Speed and depth of cut. In order to find out the effect of machining parameters on the Surface Roughness during turning, Response Surface Methodology (RSM) is used and a prediction model is developed related to average Surface Roughness (Ra) using experimental data. The surface quality is analyzed in terms of arithmetic roughness (Ra) and Power Spectral Density for uniform evaluation. In addition, a good agreement between the predicted and measured Surface Roughness is observed.
Effects of Tooth Coating Material and Finishing Agent on Bleached Enamel Surfaces by KTP Laser
Kameda, Ayumi; Masuda, Yoshiko Murakami; Teruo, Toko; Yamada, Yoshishige; Kimura, Yuichi; Tamaki, Yukimichi; Miyazaki, Takashi
Objective: The purpose of this study was to evaluate the effect of tooth coating material and finishing agent on bleached enamel surfaces after using KTP laser with 27% hydrogen peroxide. Background data: There have been few reports on the effects of tooth coating materials and finishing agents after bleaching. Methods: After 40 crowns of human extracted maxillary incisors were bleached by KTP laser, bleached enamels were finished with fluoride only or both of fluoride and nano-hydroxyapatite as a finishing agent. After application(s) of fluoride and/or finishing agent, the enamel surfaces were divided into 2 groups, which were covered with the coating material or without coating material. After application of coating materials, all specimens were kept for 2 weeks at 37°C of 100% humidity. After removing the coating material, color changing was measured and enamel surfaces were examined by scanning electron microscopy (SEM). Results: SEM observation of enamel surfaces treated the fluoride gel, finishing agent and coating material showed the most flattered surface compared to other groups. By measuring the color changing, few color changing was observed on the enamel surfaces treated the fluoride gel, finishing agents and coating material. Conclusion: These results suggested that applications of fluoride gel, finishing agent and coating material made the enamel-surfaces flattered and kept effects of bleaching, could prevent the re-coloration. After applications of fluoride gel and finishing agent, covering the bleached-enamel surfaces with the coating material enhanced the keeping whiteness. It would give the patients satisfaction of whiteness. PMID:24155557
Study of microstructure of surface layers of low-carbon steel after turning and ultrasonic finishing
NASA Astrophysics Data System (ADS)
Kovalevskaya, Zh. G.; Ivanov, Yu. F.; Perevalova, O. B.; Klimenov, V. A.; Uvarkin, P. V.
Profilometry and optical and transmission electron microscopy are used to examine the microstructure of surface layers of a low-carbon ferrite-pearlite steel subjected to turning and ultrasonic finishing. It is shown that turning peaks and valleys have different microstructures, which stipulates manifestation of technological hereditary when processing surfaces of machined parts. Ultrasonic finishing causes the severe plastic deformation of the surface layer, which favors the elimination of a technological heredity that is acquired during turning.
An evaluation of wear of human enamel opposed by ceramics of different surface finishes
Mulay, Gauri; Dugal, Ramandeep; Buhranpurwala, Murtuza
Statement of Problem: Surface of porcelain restoration is a matter of clinical concern because of its abrasive action on the opposing enamel. Purpose: This study comparatively evaluated wear of enamel when opposed by three different surface finishes of ceramic. Materials and Methods: A total of 60 metal-ceramic discs (10 mm × 2 mm) with different surface finishes were fabricated. They were divided into four groups of autoglazed ceramic surface, over glazed ceramic surface, ceramic surface polished with Shofu polishing kit and ceramic surface polished with DFS polishing wheels and paste. Each group comprised of 15 discs. Sixty human teeth samples were prepared from freshly extracted, unrestored, caries free, nonattrited maxillary first premolars. Each tooth sample was weighed before wear testing using AT200 Mettler Toledo electronic analytical balance of 0.0001 g accuracy. Occlusal surfaces of these teeth were then abraded against the substrates in a wear machine for a total of 10,000 cycles. Each tooth sample was weighed after 5000 cycles and after the total of 10,000 cycles, respectively, using the same balance. Differences in weight of tooth samples before and after wear testing were evaluated statistically using one-way analysis of variance and Bonferroni's correction for multiple group comparisons. Results: The values obtained for percentage weight loss after 10,000 cycles for over glazed ceramic surface were marginally higher than values obtained for autoglazed surface. It was observed that values obtained for percentage weight loss by polished ceramic after 10,000 cycles were statistically less as compared to the values obtained with autoglazed and over glazed ceramic surface (P < 0.001). There was no statistically significant difference between the values obtained by polished ceramic surfaces of two different groups. Conclusion: Enamel wear produced by polished porcelain is substantially less than autoglazed and over glazed porcelain. No significant
Actual surface finishing shop examples are used to illustrate the use of process chemistry understanding and analyses to identify immediate, interim and permanent response options for industrial waste water treatment plant (IWTP) upset problems caused by chelating agents. There i...
An improved evaluation of surface finish with a three dimensional tester
NASA Technical Reports Server (NTRS)
The design and programming of an automated three dimensional surface finish tester is described. The device produces a three dimensional image of the microscopic texture of the examined surface. The surface finish tester presents the following advantages over conventional profilometry: (1) more complete exploration of surface texture by successive probe sweeps; (2) automation of measuring and calculating; (3) more accurate representation of the derived parameters; (4) analysis of the degree of homogeneity of the surface; (5) three dimensional graphic representation accurately depicting the state of the surface; (6) detection of local imperfections; and (7) detection of scoring that occurred during machining.
Three common finishing treatments of stainless steel that are used for equipment during poultry processing were tested for resistance to bacterial contamination. Methods were developed to measure attached bacteria and to identify factors that make surface finishes susceptible or ...
Effects of surface finish and mechanical training on Ni-Ti sheets for elastocaloric cooling
NASA Astrophysics Data System (ADS)
Engelbrecht, Kurt; Tušek, Jaka; Sanna, Simone; Eriksen, Dan; Mishin, Oleg V.; Bahl, Christian R. H.; Pryds, Nini
Elastocaloric cooling has emerged as a promising alternative to vapor compression in recent years. Although the technology has the potential to be more efficient than current technologies, there are many technical challenges that must be overcome to realize devices with high performance and acceptable durability. We study the effects of surface finish and training techniques on dog bone shaped polycrystalline samples of NiTi. The fatigue life of several samples with four different surface finishes was measured and it was shown that a smooth surface, especially at the edges, greatly improved fatigue life. The effects of training both on the structure of the materials and the thermal response to an applied strain was studied. The load profile for the first few cycles was shown to change the thermal response to strain, the structure of the material at failure while the final structure of the material was weakly influenced by the surface finish.
Improving surface figure and microroughness of IR materials and diamond turned surfaces with magnetorheological finishing (MRF)
NASA Astrophysics Data System (ADS)
Supranowitz, Christopher; Hall, Christopher; Dumas, Paul; Hallock, Bob
Optics manufactured for infrared (IR) applications are commonly produced using single point diamond turning (SPDT). SPDT can efficiently produce spherical and aspheric surfaces with microroughness and figure error that is often acceptable for use in this region of the spectrum. The tool marks left by the diamond turning process cause high surface microroughness that can degrade performance when used in the visible region of the spectrum. For multispectral and high precision IR applications, surface figure may also need to be improved beyond the capabilities of the SPDT process. Magnetorheological finishing (MRF®) is a deterministic, subaperture polishing technology that has proven to be very successful at simultaneously improving both surface microroughness and surface figure on spherical, aspheric, and most recently, freeform surfaces. MRF has been used on many diamond turned IR materials to significantly reduce surface microroughness from tens of nanometers to below 1 nm. MRF has also been used to successfully correct figure error on several IR materials that are not diamond turnable. This paper will show that the combination of SPDT and MRF technologies enable the manufacture of high precision surfaces on a variety of materials including calcium fluoride, silicon, and nickel-plated aluminum. Results will be presented for microroughness reduction and surface figure improvement, as well as for smoothing of diamond turning marks on an off-axis part. Figure correction results using MRF will also be presented for several other IR materials including sapphire, germanium, AMTIR, zinc sulfide, and polycrystalline alumina (PCA).
A comparison of several surface finish measurement methods as applied to ground ceramic and metal surfaces
Blau, P.J.; Martin, R.L.; Riester, L.
Surface finish is one of the most common measures of surface quality of ground ceramics and metal parts and a wide variety of methods and parameters have been developed to measure it. The purpose of this investigation was to compare the surface roughness parameters obtained on the same two specimens from three different types of measuring instruments: a traditional mechanical stylus system, a non-contact laser scanning system, and the atomic force microscope (two different AFM systems were compared). The same surface-ground silicon nitride and Inconel 625 alloy specimens were used for all measurements in this investigation. Significant differences in arithmetic average roughness, root-mean-square roughness, and peak-to-valley roughness were obtained when comparing data from the various topography measuring instruments. Non-contact methods agreed better with the others on the metal specimen than on the ceramic specimen. Reasons for these differences include the effective dimensions and geometry of the probe with respect to the surface topography; the reflectivity of the surface, and the type of filtering scheme Results of this investigation emphasize the importance of rigorously specifying the manner of surface roughness measurement when either reporting roughness data or when requesting that roughness data be provided.
Study of the influence of reference system in surface finishing parameters evaluation
NASA Astrophysics Data System (ADS)
Sanz, A.; Fernández, R.; Pindado, S.; Núñez, P.
In the present paper the influence of the reference system with regard to the characterization of the surface finishing is analyzed. The effect of the reference system's choice on the most representative surface finishing parameters (e.g. roughness average Ra and root mean square values Rq) is studied. The study can also be applied to their equivalent parameters in waviness and primary profiles. Based on ISO and ASME standards, three different types of regression lines (central, mean and orthogonal) are theoretically and experimentally analyzed, identifying the validity and applicability fields of each one depending on profile's geometry.
Effect of Blade-surface Finish on Performance of a Single-stage Axial-flow Compressor
NASA Technical Reports Server (NTRS)
Moses, Jason J; Serovy, George, K
A set of modified NACA 5509-34 rotor and stator blades was investigated with rough-machine, hand-filed, and highly polished surface finishes over a range of weight flows at six equivalent tip speeds from 672 to 1092 feet per second to determine the effect of blade-surface finish on the performance of a single-stage axial-flow compressor. Surface-finish effects decreased with increasing compressor speed and with decreasing flow at a given speed. In general, finishing blade surfaces below the roughness that may be considered aerodynamically smooth on the basis of an admissible-roughness formula will have no effect on compressor performance.
Surface-finish effects on the high-cycle fatigue of Alloy 718
Korth, G.E.
Alloy 718 us a precipitation-hardening nickel-base superalloy that is being specified for various components for liquid-meal fast breeder reactors (LMFBRs). This alloy maintains high strength at elevated temperatures making it a desirable structural material. But the property that justifies most LMFBR applications is the alloy's resistance to thermal striping damage due to its high fatigue endurance strength. Thermal striping is a high-cycle fatigue phenomenon caused by thermal stresses from the fluctuating mixing action of sodium streams of differing temperatures impinging on the metal surfaces. Most of the design data is generated from laboratory fatigue specimens with carefully controlled surface finishes prepared with a low-stress grind and buffed to a surface finish 8--12 in. Since Alloy 718 has been shown to be quite notch sensitive under cyclic loading, the detrimental effect on the high-cycle fatigue properties caused by shop surface finishes of actual components has been questioned. This report examines some of the surface finishes that could be produced in a commercial shop on an actual component.
Mathematical modeling of surface roughness in magnetic abrasive finishing of BK7 optical glass.
Pashmforoush, Farzad; Rahimi, Abdolreza; Kazemi, Mehdi
Magnetic abrasive finishing (MAF) is one of the advanced machining processes efficiently used to finish hard-to-machine materials. Simulation and modeling of the process is of particular importance to understand the mechanics of material removal and consequently achieve a high-quality surface with a minimum of surface defects. Hence, in this paper, we performed a numerical-experimental study to mathematically model the surface roughness during the MAF of BK7 optical glass. For this purpose, the initial roughness profile was estimated using fast Fourier transform (FFT) and a Gaussian filter. We obtained the final surface profile based on the material removal mechanisms and the corresponding chipping depth values evaluated by finite element analysis. We then validated experimentally the simulation results in terms of the arithmetic average surface roughness (R(a ). The comparison between the obtained results demonstrates that the theoretical and experimental findings are in good agreement when predicting the parameters' effect on surface roughness behavior. PMID:26479596
Chemical milling solution produces smooth surface finish on aluminum
NASA Technical Reports Server (NTRS)
Lorenzen, H. C.
Elementary sulfur mixed into a solution of caustic soda and salts produces an etchant which will chemically mill end-grain surfaces on aluminum plate. This composition results in the least amount of thickness variation and pitting.
Impact of surface finishes on the flexural strength and fracture toughness of In-Ceram Zirconia.
Manawi, Manal; Ozcan, Mutlu; Madina, Manal; Cura, Cenk; Valandro, Luiz Felipe
Dental restorations made of zirconia are usually selectively adjusted chairside to eliminate occlusal or internal interferences that can impair the mechanical properties of ceramic framework material. Effects of polishing procedures on zirconia after chipping or simply glazing the monolithic zirconia restorations are not known. This study evaluated the effects of different surface treatment procedures--namely, glazing or grinding, finishing, and polishing regimens--on the flexural strength and fracture toughness of a zirconia core material. Forty zirconia specimens were prepared and divided into two main groups (n = 20) according to the type of surface treatment (glazed or ground, finished, and polished). Each group was further divided into two subgroups (n = 10) according to type of mechanical test (flexural strength and fracture toughness). The roughness measurements were performed before mechanical testing. Qualitative evaluation of representative specimens of each subgroup was performed using SEM. The surface roughness mean (μm; ± standard deviations) recorded for the glazed specimens (0.94 ± 0.2) was significantly lower than that of the finished and polished group (3.01 ± 0.1) (P < 0.05). The glazed zirconia showed significantly higher flexural strength (385.4 ± 45.4 MPa) and fracture toughness (6.07 ± 1 MPa.m½) values than the ground, finished, polished zirconia (302.4 ± 47.6 MPa and 2.14 ± 0.5 MPa.m½) (P = 0.002 and P < 0.001 for flexural strength and fracture toughness, respectively). A smooth topographic pattern after glazing could not be obtained after finishing and polishing. Grinding, finishing, and polishing markedly decreased the flexural strength and fracture toughness of zirconia compared to the glazed groups. PMID:22414507
Technology Transfer Automated Retrieval System (TEKTRAN)
Corrosion, an important factor for the durability of a metal finish after exposure to water and chemicals during processing, is a real concern for many wet process industries. The effects of rouging, corrosion, and biofouling are costly problems on the surface of stainless steel, the most common mat...
Effect of processing parameters on surface finish for fused deposition machinable wax patterns
NASA Technical Reports Server (NTRS)
Roberts, F. E., III
This report presents a study on the effect of material processing parameters used in layer-by-layer material construction on the surface finish of a model to be used as an investment casting pattern. The data presented relate specifically to fused deposition modeling using a machinable wax.
Evaluation of ENEPIG and Immersion Silver Surface Finishes Under Drop Loading
NASA Astrophysics Data System (ADS)
Pearl, Adam; Osterman, Michael; Pecht, Michael
The effect of printed circuit board surface finish on the drop loading reliability of ball grid array (BGA) solder interconnects has been examined. The finishes examined include electroless nickel/electroless palladium/immersion gold (ENEPIG) and immersion silver (ImAg). For the ENEPIG finish, the effect of the Pd plating layer thickness was evaluated by testing two different thicknesses: 0.05 μm and 0.15 μm. BGA components were assembled onto the boards using either eutectic Sn-Pb or Sn-3.0Ag-0.5Cu (SAC305) solder. Prior to testing, the assembled boards were aged at 100°C for 24 h or 500 h. The boards were then subjected to multiple 1500-g drop tests. Failure analysis indicated the primary failure site for the BGAs to be the solder balls at the board-side solder interface. Cratering of the board laminate under the solder-attached pads was also observed. In all cases, isothermal aging reduced the number of drops to failure. The components soldered onto the boards with the 0.15- μm-Pd ENEPIG finish with the SAC305 solder had the highest characteristic life, at 234 drops to failure, compared with the other finish-solder combinations.
Effect finishing and polishing procedures on the surface roughness of IPS Empress 2 ceramic
Nishida, Rodrigo; Elossais, André Afif; Lima, Darlon Martins; Reis, José Mauricio Santos Nunes; Campos, Edson Alves; de Andrade, Marcelo Ferrarezi
Objective. To evaluate the surface roughness of IPS Empress 2 ceramic when treated with different finishing/polishing protocols. Materials and methods. Sixteen specimens of IPS Empress 2 ceramic were made from wax patterns obtained using a stainless steel split mold. The specimens were glazed (Stage 0–S0, control) and divided into two groups. The specimens in Group 1 (G1) were finished/polished with a KG Sorensen diamond point (S1), followed by KG Sorensen siliconized points (S2) and final polishing with diamond polish paste (S3). In Group 2 (G2), the specimens were finished/polished using a Shofu diamond point (S1), as well as Shofu siliconized points (S2) and final polishing was performed using Porcelize paste (S3). After glazing (S0) and following each polishing procedure (S1, S2 or S3), the surface roughness was measured using TALYSURF Series 2. The average surface roughness results were analyzed using ANOVA followed by Tukey post-hoc tests (α = 0.01) Results. All of the polishing procedures yielded higher surface roughness values when compared to the control group (S0). S3 yielded lower surface roughness values when compared to S1 and S2. Conclusions. The proposed treatments negatively affected the surface roughness of the glazed IPS Empress 2 ceramic. PMID:22724660
Surface finish produced on three resin composites by new polishing systems.
St-Georges, Annie J; Bolla, Marc; Fortin, Daniel; Muller-Bolla, Michelle; Thompson, Jeffrey Y; Stamatiades, Perry J
This study evaluated the surface finish of three direct resin composites polished with three different systems. Disk-shaped specimens (n=16 per material; phi=8.0 mm x h=2.0 mm) were formed in a stainless steel mold by packing uncured material, either a hybrid composite (Z250, 3M ESPE) or two micro-hybrid composites (Point 4, Kerr; Esthet-X, Dentsply), and light-cured from the top and the bottom surfaces with a light-emitting diode (LED) curing unit (NRG, Dentsply). After storing the specimens in deionized water at 37 degrees C for seven days, one side of each specimen was finished through 1200-grit SiC abrasive (Buehler). Five specimens of each resin composite were randomly assigned to one of the three polishing systems (Identoflex, Kerr; Pogo, Dentsply; Sof-Lex, 3M ESPE). Manufacturers' instructions were followed during the polishing procedures. The average surface roughness (Ra) was determined by generating tracings across the polished surface of each disk using a scanning profilometer (Surfanalyzer System 5000, Federal Products Co). The results were analyzed by Kruskal-Wallis and Mann and Whitney tests (p < or = 0.05). The smoothest surfaces were produced with the celluloid strip (control group) on all the resin composites tested. The aluminum oxide disks (Sof-Lex) produced a statistically equivalent surface finish (Ra) on the three resin composites. The lowest mean roughness values were recorded with diamond micropolisher disks (PoGo) on the hybrid composite (Z250). Overall, the two new polishing systems, Identoflex and PoGo, created a comparable surface finish to that produced by the Sof-Lex system on all three resin composites. PMID:16268393
Pb-free surface-finishing on electronic components' terminals for Pb-free soldering assembly
Tanaka, Hitoshi; Tanimoto, Morimasa; Matsuda, Akira; Uno, Takeo; Kurihara, Masaaki; Shiga, Shoji
Pb-free solderable surface finishing is essential to implement Pb-free solder assembly in order to meet with the growing demand of environmental consciousness to eliminate Pb from electronic products. Two types of widely applicable Pb-free surface finishing technologies are developed. One is the multilayer-system including Pd with Ni undercoat. Heat-resistance of Pd enables whole-surface-plating on to leadframe before IC-assembling process. The other is the double-layer-system with low-melting-point-materials, for example, thicker Sn underlayer and thinner Sn-Bi alloy overlayer, dilutes Sn-Bi alloy's defects of harmful reactivity along with substrate metal and mechanical brittleness with keeping its advantages of solder-wettability and no whisker.
Influence law of structural characteristics on the surface roughness of a magnetorheological-finished KDP crystal.
Chen, Shaoshan; Li, Shengyi; Hu, Hao; Li, Qi; Tie, Guipeng
A new nonaqueous and abrasive-free magnetorheological finishing (MRF) method is adopted for processing potassium dihydrogen phosphate (KDP) crystal due to its low hardness, high brittleness, temperature sensitivity, and water solubility. This paper researches the influence of structural characteristics on the surface roughness of MRF-finished KDP crystal. The material removal by dissolution is uniform layer by layer when the polishing parameters are stable. The angle between the direction of the polishing wheel's linear velocity and the initial turning lines will affect the surface roughness. If the direction is perpendicular to the initial turning lines, the polishing can remove the lines. If the direction is parallel to the initial turning lines, the polishing can achieve better surface roughness. The structural characteristic of KDP crystal is related to its internal chemical bonds due to its anisotropy. During the MRF finishing process, surface roughness will be improved if the structural characteristics of the KDP crystal are the same on both sides of the wheel. The processing results of (001) plane crystal show we can get the best surface roughness (RMS of 0.809 nm) if the directions of cutting and MRF polishing are along the (110) direction. PMID:25402879
Evaluation of the surface roughness in dental ceramics submitted to different finishing and polishing methods.
Vieira, Alex C; Oliveira, Mario C S; Lima, Emilena M C X; Rambob, Isabel; Leite, Mariana
Ceramic restorations have been widely used in dentistry. These restorations often require intraoral adjustment with diamond burs after their cementation causing increasing roughness of the ceramic surface. Consequently some finishing and polishing methods have been used to minimize this occurrence. The aim of this study is to evaluate the roughness of the ceramic surfaces submitted to different finishing and polishing methods. 144 specimens of VITAVM(®)7, VM(®)9 and VM(®)13 (VITA Zahnfabrik) ceramics were fabricated and submitted to grinding using diamond burs. They were then divided into 15 groups (five of each ceramic type). Groups 1, 6 and 11-positive control (Glaze); Groups 2, 7 and 12-negative control (no polishing); Groups 3, 8 and 13-polished with abrasive rubbers (Edenta), felt disc and diamond polishing past; Groups 4, 9 and 14-polished with abrasive rubbers (Shofu), felt disc and diamond polishing past; Groups 5, 10 and 15-polished with aluminum oxide discs (Sof-Lex, 3M-ESPE), felt disc and diamond polishing paste. The roughness of the samples surfaces were measured using the rugosimeter Surfcorder SE 1700 and the data were submitted to statistical analysis using ANOVA and Tukey test at a level of significance of 5 %. There was statistically significance difference between the positive control groups and the other groups in all the ceramic types. Mechanical finishing and polishing methods were not able to provide a surface as smooth as the glazed surface for the tested ceramics. To assist dental practitioners to select the best finishing and polishing methods for the final adjustment of the ceramic restorations. PMID:24431749
Analysis of machining accuracy during free form surface milling simulation for different milling strategies
NASA Astrophysics Data System (ADS)
Matras, A.; Kowalczyk, R.
The analysis results of machining accuracy after the free form surface milling simulations (based on machining EN AW- 7075 alloys) for different machining strategies (Level Z, Radial, Square, Circular) are presented in the work. Particular milling simulations were performed using CAD/CAM Esprit software. The accuracy of obtained allowance is defined as a difference between the theoretical surface of work piece element (the surface designed in CAD software) and the machined surface after a milling simulation. The difference between two surfaces describes a value of roughness, which is as the result of tool shape mapping on the machined surface. Accuracy of the left allowance notifies in direct way a surface quality after the finish machining. Described methodology of usage CAD/CAM software can to let improve a time design of machining process for a free form surface milling by a 5-axis CNC milling machine with omitting to perform the item on a milling machine in order to measure the machining accuracy for the selected strategies and cutting data.
Finished surface texture, abrasion resistance, and porosity of Aspa glass-ionomer cement.
Smales, R; Joyce, K
1. With the finishing agents tested Concise had a smoother surface texture than Aspa. 2. The smoothest surface was on Concise polymerized against a Mylar matrix strip. The smoothest surface for Aspa was obtained with a silicon carbide disk. 3. Aspa abraded about three times as rapidly by volume as Concise when tested by a two-body abrasion method. 4. Significantly more air bubbles were entrapped by hand mixing within Aspa than within Concise. 5. Controlled clinical studies of the glass-ionomer cements are needed before they can be fully evaluated as restorative materials. PMID:281506
Surface finish in ultra-precision diamond turning of single-crystal silicon
NASA Astrophysics Data System (ADS)
Ayomoh, M.; Abou-El-Hossein, K.
Silicon is an optical material widely used in the production of infrared optics. However, silicon as a brittle material exhibits some difficulties when ultra-precision machined by mono-crystalline single point diamond. Finish turning of silicon with mono- crystalline diamond inserts results in accelerated tool wear rates if the right combination of the machining parameters is not properly selected. In this study, we conducted a series of machining tests on an ultra-high precision machine tool using finish turning conditions when using mono-crystalline diamond inserts with negative rake angle and relatively big nose radius. The study yields some recommendations on the best combination of machining parameters that will result in maximum material removal rates with smallest possible surface finish. In this work, standard non-controlled waviness diamond inserts having nose radius of about 1.5 mm, rake angle of negative 25°, and clearance angle of 5° were used to produce flat surfaces on silicon disk. From the results, it has been established that feed rate has the most influential effect followed by the depth of cut and cutting speed.
A novel magnetic field-assisted polishing method using magnetic compound slurry and its performance in mirror surface finishing of miniature V-grooves
NASA Astrophysics Data System (ADS)
Wang, Youliang; Wu, Yongbo; Mitsuyoshi, Nomura
A novel magnetic field-assisted polishing technique was proposed for finishing 3D structured surface using a magnetic compound (MC) slurry. The MC slurry was prepared by blending carbonyl-iron-particles, abrasive grains and α-cellulose into a magnetic fluid which contains nano-scale magnetite particles. An experimental setup was constructed firstly by installing an oscillation worktable and a unit onto a polishing machine. Then, experimental investigations were conducted on oxygen-free copper workpiece with parallel distributed linear V-grooves to clarify the influence of the polishing time and abrasive impact angle on the grooves surface qualities. It was found that (1) the groove form accuracy, i.e. the form retention rate η varied with the polishing locations. Although the form retention rate η deteriorated during the polishing process, the final η was greater than 99.4%; (2) the effective impact angle θm affected the material removal and form accuracy seriously. An increase of the absolute value θm resulted with an increase of material removal rate and a decrease of the form accuracy; (3) the work-surface roughness decreased more than 6 times compared with the original surface after MC slurry polishing. These results confirmed the performance of the proposed new magnetic field-assisted polishing method in the finishing of 3D-structured surface.
The effect of rotor blade thickness and surface finish on the performance of a small axial flow turbine
NASA Technical Reports Server (NTRS)
Roelke, R. J.; Haas, J. E.
An experimental investigation was conducted to determine the effect of blade profile inaccuracies and surface finish on the aerodynamic performance of a 11.13 cm tip diameter turbine. The as-received cast rotor blades had a significantly thicker profile than the design intent and a fairly rough surface finish. Stage test results showed an increase of one point in efficieny by smoothing the surface finish and another three points by thinning the blade profiles to near the design profile. Most of the performance gain between the as-cast thick and the thinned rotor blades both with the same surface finish, was attributed to reduced trailing edge losses of the recontoured blades.
Effects of PCB Substrate Surface Finish, Flux, and Phosphorus Content on Ionic Contamination
NASA Astrophysics Data System (ADS)
Bacior, M.; Sobczak, N.; Siewiorek, A.; Kudyba, A.; Homa, M.; Nowak, R.; Dziula, M.; Masłoń, S.
The ionic contamination on printed circuit boards (PCB) having different surface finishes was examined using ionograph. The study was performed at the RT on three types of PCBs covered with: (i) hot air solder leveling (HASL LF), (ii) electroless nickel immersion gold (ENIG), and (iii) organic surface protectant (OSP), all on Cu substrates, as well as two types of fluxes, namely EF2202 and RF800. In the group of boards without soldered components, the lowest average value of contamination was for the ENIG 18 µm surface (0.01 μg NaCl/cm2). Boards with soldered components were more contaminated (from 0.29 μg NaCl/cm2 for the HASL LF 18 µm surface). After spraying boards with fluxing agents, the values of contaminants were the highest. The influence of phosphorus content in Ni-P layer of ENIG finish on ionic contamination was examined. In the group of PCBs with Au coating, the smallest amount of surface contaminants (0.32 μg NaCl/cm2) was for Ni-2-5%P layer. PCBs with Ni-11%P layer were higher contaminated (0.47 μg NaCl/cm2), and another with Ni-8%P layer had 0.81 μg NaCl/cm2. PCBs without Au coating, had the lowest contamination (0.48 μg NaCl/cm2) at phosphorous content equal 11%P. Higher contamination (0.67 μg NaCl/cm2) was at 2-5%P, up to 1.98 μg NaCl/cm2 for 8% of P. Boards with Au finish have lower value of contamination than identical boards without Au layer thus contributing to better reliability of electronic assemblies, since its failures due to current leakage and corrosion can be caused by contaminants.
Role of surface finishing on pitting corrosion of a duplex stainless steel in seawater
NASA Astrophysics Data System (ADS)
Salah-Rousset, N. Ben; Chaouachi, M. A.; Chellouf, A.
Localized corrosion of duplex UNS S32550 stainless steel in seawater was investigated in the laboratory and in field trials for several surface finish conditions: polished, ground, and sandblasted. Electrochemical data obtained by polarization curves showed that the smoother, polished surface had better characteristics (higher pitting and protection potentials) than the ground or sandblasted surfaces. However, despite its high degree of roughness, the sandblasted surface was the most resistant in field conditions, exhibiting the lowest number of sites attacked. Internal compressive stresses created by sandblasting seem also to have an "unsensitizing" effect on sensitized zones that exist in cast steel (due to repairs of mold defects), reducing its susceptibility to microbiologically influenced corrosion (MIC). Such stresses are not generated in polished or ground surfaces, and localized MIC attack can occur.
The effects of surface finish and grain size on the strength of sintered silicon carbide
NASA Technical Reports Server (NTRS)
You, Y. H.; Kim, Y. W.; Lee, J. G.; Kim, C. H.
The effects of surface treatment and microstructure, especially abnormal grain growth, on the strength of sintered SiC were studied. The surfaces of sintered SiC were treated with 400, 800 and 1200 grit diamond wheels. Grain growth was induced by increasing the sintering times at 2050 C. The beta to alpha transformation occurred during the sintering of beta-phase starting materials and was often accompanied by abnormal grain growth. The overall strength distributions were established using Weibull statistics. The strength of the sintered SiC is limited by extrinsic surface flaws in normal-sintered specimens. The finer the surface finish and grain size, the higher the strength. But the strength of abnormal sintering specimens is limited by the abnormally grown large tabular grains. The Weibull modulus increases with decreasing grain size and decreasing grit size for grinding.
New vibration-assisted magnetic abrasive polishing (VAMAP) method for microstructured surface finishing.
Guo, Jiang; Kum, Chun Wai; Au, Ka Hing; Tan, Zhi'En Eddie; Wu, Hu; Liu, Kui
In order to polish microstructured surface without deteriorating its profile, we propose a new vibration-assisted magnetic abrasive polishing (VAMAP) method. In this method, magnetic force guarantees that the magnetic abrasives can well contact the microstructured surface and access the corners of microstructures while vibration produces a relative movement between microstructures and magnetic abrasives. As the vibration direction is parallel to the microstructures, the profile of the microstructures will not be deteriorated. The relation between vibration and magnetic force was analyzed and the feasibility of this method was experimentally verified. The results show that after polishing, the surface finish around microstructures was significantly improved while the profile of microstructures was well maintained. PMID:27410370
Finish ion beam treatment of the longrange cylindrical products outer surface in automatic mode
NASA Astrophysics Data System (ADS)
Kalin, B. A.; Volkov, N. V.; Valikov, R. A.; Yashin, A. S.; Krivobokov, V. P.; Yanin, S. N.; Asainov, O. Kh; Yurev, Yu N.
The results of using of ion-beam technologies methods for finish treatment of metal products are presented. The experiments were performed at the installation ILUR-03, which allows the operation of cleaning, polishing and surface layers doping of the material of unlimited length cylindrical samples by radial Ar+ ions beam with energy up to 5 keV. The tubes from zirconium alloy E110 up to 500 mm length were used as samples for investigation. It is shown that selected automatic treatment modes reduce the surface roughness over the entire length of the samples and increase uniformity of the surface layer without observable effect on the bulk properties of material. Treatment promotes the formation of oxide films with improved defensive properties.
The Effect of Composition on the Surface Finish of PS400: A New High Temperature Solid Lubricant Coating
NASA Technical Reports Server (NTRS)
DellaCorte, Christopher; Stanford, malcolm K.; Thomas, Fransua; Edmonds, Brian J.
A new composite, multi-constituent, solid lubricant coating, NASA PS400, developed for high temperature tribological applications, exhibits a smoother surface finish after grinding and polishing than its predecessors PS200 and PS300. In this paper, the baseline composition of PS400 is modified to investigate each individual constituent s role on the achievable surface finish through a series of coating deposition, grinding, and polishing experiments. Furthermore, to explore the limits of compositional tailoring for improved tribological performance, several PS400 coatings were doped with additional solid lubricants (graphite, MoS2 and BN) and tribologically tested. The test results clearly showed that, compared to PS300 coatings, PS400 achieves a smoother surface finish via a reduced lubricant content. Coatings prepared with higher than the baseline level (10 wt%) of lubricants exhibited higher final surface roughness than the earlier generation PS300 coatings. Reducing or eliminating the one or both lubricants (fluorides or silver) did not further improve the surface finish suggesting that the current composition of PS400 is near optimal with respect to surface finish. Lastly, attempts to improve the poor initial room temperature tribological behavior of PS400 via the addition of traditional solid lubricants were unsuccessful. Based upon this work and earlier results it is expected that future research will concentrate on developing methods to produce a lubricious glaze on the rubbing surface during break in to ensure that low friction and wear are rapidly achieved.
Evaluation of the Bondability of the Epoxy-Enhanced Sn-58Bi Solder with ENIG and ENEPIG Surface Finishes
NASA Astrophysics Data System (ADS)
Myung, Woo-Ram; Kim, Yongil; Jung, Seung-Boo
The effect of different surface finishes, electroless nickel immersion gold (ENIG) and electroless nickel electroless palladium immersion gold (ENEPIG), on the mechanical properties of Sn-58Bi bumps made with solder paste enhanced with epoxy were investigated. The microstructure and fracture surfaces were observed with scanning electron microscopy, and the compositions of the IMC and solder were measured using energy dispersive spectrometry and an electron probe micro-analyzer (EPMA). To evaluate the mechanical properties, low-speed shear tests and board-level drop tests were performed. The result of the shear tests showed that the bonding strength of the epoxy-enhanced Sn-58Bi solder bumps was higher than that of Sn-58Bi solder for all surface finishes, because of the epoxy surrounding the solder, and the fracture surfaces of epoxy-enhanced Sn-58Bi indicated ductile fracture in the solder joint. However, the result of the drop tests showed that samples with the ENIG and ENEPIG surface finishes had lower drop numbers compared to the sample without these surface finishes. The lower performance resulted from insufficient ejection of epoxy from the ENIG and ENEPIG surface finishes during reflow, which reduced the interfacial bonding area.
The Specification And Control Of Surface Finish-Empiricism Versus Dogmatism
NASA Astrophysics Data System (ADS)
Stout, K. J.; Obray, C.; Jungles, J.
This paper reviews the development of the analysis of surface finish from the early attempts in the nineteen thirties to the present day. The development of parameters is put in context with the techniques available and it is demonstrated that characterization based on graphical and experimental convenience has influenced industrial practice. As the requirements of manufacture and functional performance have been stretched by advancing technology many industrialists have been forced to accept that existing practices are limited, and have sought other descriptions still based on well established techniques; but these existing techniques are limited, their suitability to inprocess measurement practically non existent. It is shown that recently attempts have been made to develop optical methods of assessing surface finish using traditional parameters such as Ra. This paper suggests that it may be time to look towards a new form of specification, more suited to assessment by optical transducers, and some methods of assessment are proposed. To support this view a simple low cost device is discussed which can be calibrated to give Ra but which also presents information in a more relevant empirical way which may be more valid than the existing parameter specification.
Methodology for optimizing the electropolishing of stainless steel AISI 316L combining criteria of surface finish and dimensional precision
NASA Astrophysics Data System (ADS)
Núñez, P. J.; García-Plaza, E.; Martín, A. R.; Trujillo, R.; De la Cruz, C.
This work examines a methodology for optimizing electrochemical polishing conditions bearing in mind the criteria that enhance minimum surface roughness and dimensional precision (minimum loss of thickness). The study consisted in electrochemically polishing stainless steel AISI 316L (ISO 4954 X2CrNiMo17133E) under a combination of different temperatures (T) baths and current densities (J), and application times (t). The surface finish (ΔRa) and dimensional variations (Δh) of the electrochemically polished workpieces were assessed, and the experimental data of the variables was correlated as can be seen by the response surfaces. This methodology enables optimum working areas to be specified using the sole criteria of surface finish, or by using a combination of both criteria (minimum roughness and maximum precision). The methodology has proven to be an optimum method for selecting electrochemical polishing conditions using the combined criteria of surface finish and dimensional precision in accordance with design requirements.
Surface Roughness, Microhardness, and Microleakage of a Silorane-Based Composite Resin after Immediate or Delayed Finishing/Polishing.
Lins, Fernanda Carvalho Rezende; Ferreira, Raquel Conceição; Silveira, Rodrigo Richard; Pereira, Carolina Nemésio Barros; Moreira, Allyson Nogueira; Magalhães, Claudia Silami
Objective. This study evaluated the effect of immediate or delayed finishing/polishing using different systems on the surface roughness, hardness, and microleakage of a silorane-based composite. Material and Methods. Specimens were made with silorane-based composite (Filtek P90, 3M ESPE) and assigned to the treatments: control (light-cured); aluminum oxide discs (Sof-Lex, 3M ESPE); diamond-impregnated silicone tips (Astropol, Ivoclar Vivadent); aluminum oxide-impregnated silicone tips (Enhance, Dentsply). Half of the specimens were finished/polished immediately and the rest after 7 days. Surface roughness (Ra, μm; n = 20) and Vickers microhardness (50 g; 45 s; n = 10) were measured. Cavities were prepared in bovine incisors and filled with Filtek P90. The fillings received immediate or delayed finishing/polishing (n = 10) and were subjected to dye penetration test (0.5% basic fuchsin, 24 h). Data were analyzed by ANOVA and Scheffe, Kruskal-Wallis, and Mann-Whitney tests (p < 0.05). Results. The finishing/polishing system significantly influenced roughness and microhardness (p < 0.0001). For enamel, microleakage was not affected by the finishing/polishing system (p = 0.309). For dentin, Sof-Lex discs and Astropol points promoted greater microleakage than Enhance points (p = 0.033). Conclusion. Considering roughness, microhardness, and microleakage together, immediate finishing/polishing of a silorane-based composite using aluminum oxide discs may be recommended. PMID:26977150
Surface Roughness, Microhardness, and Microleakage of a Silorane-Based Composite Resin after Immediate or Delayed Finishing/Polishing
Lins, Fernanda Carvalho Rezende; Ferreira, Raquel Conceição; Silveira, Rodrigo Richard; Pereira, Carolina Nemésio Barros; Moreira, Allyson Nogueira; Magalhães, Claudia Silami
Objective. This study evaluated the effect of immediate or delayed finishing/polishing using different systems on the surface roughness, hardness, and microleakage of a silorane-based composite. Material and Methods. Specimens were made with silorane-based composite (Filtek P90, 3M ESPE) and assigned to the treatments: control (light-cured); aluminum oxide discs (Sof-Lex, 3M ESPE); diamond-impregnated silicone tips (Astropol, Ivoclar Vivadent); aluminum oxide-impregnated silicone tips (Enhance, Dentsply). Half of the specimens were finished/polished immediately and the rest after 7 days. Surface roughness (Ra, μm; n = 20) and Vickers microhardness (50 g; 45 s; n = 10) were measured. Cavities were prepared in bovine incisors and filled with Filtek P90. The fillings received immediate or delayed finishing/polishing (n = 10) and were subjected to dye penetration test (0.5% basic fuchsin, 24 h). Data were analyzed by ANOVA and Scheffe, Kruskal-Wallis, and Mann-Whitney tests (p < 0.05). Results. The finishing/polishing system significantly influenced roughness and microhardness (p < 0.0001). For enamel, microleakage was not affected by the finishing/polishing system (p = 0.309). For dentin, Sof-Lex discs and Astropol points promoted greater microleakage than Enhance points (p = 0.033). Conclusion. Considering roughness, microhardness, and microleakage together, immediate finishing/polishing of a silorane-based composite using aluminum oxide discs may be recommended. PMID:26977150
Interferometric And Microscopic Measurements Of Surface Finish Appearance Evaluations Of Ophthalmic Lens Edges
NASA Astrophysics Data System (ADS)
Gamble, M.; Mezghani, S.; El Mansori, M.; Divo, F.
Surface appearance and product material integrity are important features that will affect product functionality, reliability and customer confidence. Yet despite this, and perhaps surprisingly, lens surface inspection is still undertaken visually with undefined criteria, varying levels of quality expertise, and differing moods of inspectors. In this paper, an objective quality inspection method for the polished edge of ophthalmic lenses is developed. Four defect categorizes have been indentified on the machined edge of non-acceptable lenses: chatter marks, linear, creep and cracks. Chatter matters have an irregular surface with waviness. The linear defect has a linear defect along the lens' edge surface. Creep has deformation of the surface due to the material removal process. Cracks have cracks along the surface of the lens. The developed technique was applied to several ophthalmic lens materials (Polycarbonate, CR39, high index materials) that contain defects of diverse shapes and sizes in different locations. Results show the effectiveness of the developed inspection technique for ophthalmic lens quality assurance and defect identification. It was also found that there is a correlation between the scale-sensitive fractal dimension parameter and surface finish appearance.
Toward a production-line classification of metallic satin-finished surfaces using coherent light
NASA Astrophysics Data System (ADS)
Lopez de Meneses, Yuri; Meylan, Gregoire; Monay, Florent; Jacot, Jacques
Some manufacturing processes, such as satin finish on stainless steel parts for the watchmaking and biomedical industries, apply purely aesthetic, global criteria for their quality control. This control is currently performed by human operators, and is found to be subjective, due to variability in operator judgement. This project aims to develop a device for automatic, production-line classification of satin finish according to the aesthetic criteria currently applied in the watchmaking industry. We exploit two coherent light phenomena to produce features to classify the parts into the same classes indicated by human operators. The analysis of the optical Fourier transform and the scattering pattern are used to generate high-dimensional feature vectors for their subsequent classification. The vectors, corresponding to different regions of the part surface, are classified using Principal Component Analysis and Kohonen networks. Experimental results show that both optical phenomena provide features capable of discriminating between conforming and nonconforming parts. Classification is simple enough to afford an inspection in under 1 s and its robustness has also been verified. We have thus completed a first step towards a simple, production-line device capable of providing an automatic, objective evaluation based on aesthetic quality criteria.
Structural and Electronic Properties of Gold Contacts on CdZnTe with Different Surface Finishes for Radiation Detector Applications
NASA Astrophysics Data System (ADS)
Tari, S.; Aqariden, F.; Chang, Y.; Ciani, A.; Grein, C.; Li, Jin; Kioussis, N.
State-of-the-art room-temperature, high-resolution x-ray and gamma-ray semiconductor detectors can be fabricated from CdZnTe (CZT) crystals. The structural and electronic properties of the CZT surface, especially the contact interfaces, can have a substantial effect on radiation detector performance, for example leakage current, signal-to-noise ratio, and energy resolution, especially for soft x-rays and large pixilated arrays. Atomically smooth and defect-free surfaces are desirable for high-performance CZT-based detectors; chemo-mechanical polishing (CMP) is typically performed to produce such surfaces. The electrical behavior of the metal/CZT interface varies substantially with surface preparation before contact deposition, and with choice of metal and deposition technique. We report a systematic study of the structural and electronic properties of gold (Au) contacts on CZT prepared with different surface finishes. We observed subsurface damage under Au contacts on CMP-finished CZT and abrupt interfaces for Au on chemically-polished (CP) CZT. Schottky barrier formation was observed for Au contacts, irrespective of surface finish, and less charge trapping and low surface resistance were observed for CP-finished surfaces. Pre-deposition surface treatment produced interfaces free from oxide layers.
Accuracy assessment of NLCD 2006 land cover and impervious surface
Wickham, James D.; Stehman, Stephen V.; Gass, Leila; Dewitz, Jon; Fry, Joyce A.; Wade, Timothy G.
Release of NLCD 2006 provides the first wall-to-wall land-cover change database for the conterminous United States from Landsat Thematic Mapper (TM) data. Accuracy assessment of NLCD 2006 focused on four primary products: 2001 land cover, 2006 land cover, land-cover change between 2001 and 2006, and impervious surface change between 2001 and 2006. The accuracy assessment was conducted by selecting a stratified random sample of pixels with the reference classification interpreted from multi-temporal high resolution digital imagery. The NLCD Level II (16 classes) overall accuracies for the 2001 and 2006 land cover were 79% and 78%, respectively, with Level II user's accuracies exceeding 80% for water, high density urban, all upland forest classes, shrubland, and cropland for both dates. Level I (8 classes) accuracies were 85% for NLCD 2001 and 84% for NLCD 2006. The high overall and user's accuracies for the individual dates translated into high user's accuracies for the 2001–2006 change reporting themes water gain and loss, forest loss, urban gain, and the no-change reporting themes for water, urban, forest, and agriculture. The main factor limiting higher accuracies for the change reporting themes appeared to be difficulty in distinguishing the context of grass. We discuss the need for more research on land-cover change accuracy assessment.
Three-dimensional evaluation of surface roughness of resin composites after finishing and polishing
Nair, Veena S; Sainudeen, Shan; Padmanabhan, Prabeesh; Vijayashankar, L V; Sujathan, Unu; Pillai, Rajesh
Aim: This study aims to investigate the effects of finishing and polishing procedures on four novel resin composites using three-dimensional optical profilometer. Materials and Methods: Four composites classified according to their filler size, were selected: Filtek™ Z350 XT/Nanofill (3M™ ESPE™), Esthet-X HD/Hybrid (Dentsply Caulk), Te Econom/Microfill (Ivoclar Vivadent®), Tetric EvoCeram® /Nanohybrid (Ivoclar Vivadent®). Composite specimens were made in Plexiglass mold and polished with Soflex (3M ESPE), Enhance + Pogo (Dentsply Caulk). Both the systems were used according to the manufacturers' instructions, and the polished surfaces were assessed with an optical profilometer. Statistical Analysis Used: Kruskal-Wallis test and further pairwise comparison were performed by Mann-Whitney test. Results: The smoothest surfaces for all the resin composites tested were obtained from the Mylar strip; statistically significant differences were observed among them (P = 0.001). The order of composites was ranked from the lowest to highest surface roughness; Filtek Z350 XT < Te Econom < Tetric EvoCeram < Esthet XHD. Pairwise multiple comparison with Mann-Whitney test showed Filtek Z350 to have the smoothest surface and the least with Teric EvoCeram. Among the polishing systems, Soflex showed the smoothest surface and was significantly different from Pogo (P = 0.046). Conclusions: The effectiveness of the polishing systems seems to be dependent on the material used, treatment modality and also on the filler particle size. PMID:26957802
Effect of surface roughness and stainless steel finish on Listeria monocytogenes attachment and biofilm formation.
Rodriguez, Andres; Autio, Wesley R; McLandsborough, Lynne A
The purpose of this study was to evaluate the effect of surface roughness (Ra) and finish of mechanically polished stainless steel (Ra = 0.26 +/- 0.05, 0.49 +/- 0.10, and 0.69 +/- 0.05 microm) and electropolished stainless steel (Ra = 0.16 +/- 0.06, 0.40 +/- 0.003, and 0.67 +/- 0.02 microm) on Listeria adhesion and biofilm formation. A four-strain cocktail of Listeria monocytogenes was used. Each strain (0.1%) was added to 200 ml of tryptic soy broth (TSB), and coupons were inserted to the mixture for 5 min. For biofilm formation, coupons with adhesive cells were incubated in 1:20 diluted TSB at 32 degrees C for 48 h. The experiment was performed by a randomized block design. Our results show that the level of Listeria present after 48 h of incubation (mean = 7 log CFU/cm2) was significantly higher than after 5 min (mean = 6.0 log CFU/cm2) (P < 0.01). No differences in initial adhesion were seen in mechanically finished (mean = 6.7 log CFU/cm2) when compared with electropolished stainless steel (mean = 6.7 log CFU/cm2) (P > 0.05). Listeria initial adhesion (values ranged from 5.9 to 6.1 log CFU/cm2) or biofilm formation (values ranged from 6.9 to 7.2 log CFU/cm2) was not significantly correlated with Ra values (P > 0.05). Image analysis with an atomic force microscope showed that bacteria did not colonize the complete surface after 48 h but were individual cells or grouped in microcolonies that ranged from 5 to 10 microm in diameter and one to three cell layers in thickness. Exopolymeric substances were observed to be associated with the colonies. According to our results, electropolishing stainless steel does not pose a significant advantage for food sanitation over mechanically finished stainless steel. PMID:18236679
Control of formaldehyde and TVOC emission from wood-based flooring composites at various manufacturing processes by surface finishing.
Kim, Sumin
This paper assesses the reproducibility of testing formaldehyde and TVOC emission behavior from wood flooring composites bonded by urea-formaldehyde resin at various manufacturing steps for surface finishing materials. The surface adhesion step of laminate flooring for this research was divided into two steps; HDF only and HDF with LPMs. In the case of engineered flooring, the manufacturing steps were divided into three steps; plywood only, fancy veneer bonded on plywood and UV coated on fancy veneer with plywood. Formaldehyde and VOCs emission decreased at the process of final surface finishing materials; LPMs were applied on the surface of HDF for laminate flooring. Although emissions increased when fancy veneer was bonded onto plywood in the case of engineered flooring, emission was dramatically reduced up to similar level with plywood only when final surface finishing; UV-curable coating was applied on fancy veneer. This study suggests that formaldehyde and VOCs emission from floorings can be controlled at manufacturing steps for surface finishing. PMID:19467783
Choice of crystal surface finishing for a dual-ended readout depth-of-interaction (DOI) detector.
Fan, Peng; Ma, Tianyu; Wei, Qingyang; Yao, Rutao; Liu, Yaqiang; Wang, Shi
The objective of this study was to choose the crystal surface finishing for a dual-ended readout (DER) DOI detector. Through Monte Carlo simulations and experimental studies, we evaluated 4 crystal surface finishing options as combinations of crystal surface polishing (diffuse or specular) and reflector (diffuse or specular) options on a DER detector. We also tested one linear and one logarithm DOI calculation algorithm. The figures of merit used were DOI resolution, DOI positioning error, and energy resolution. Both the simulation and experimental results show that (1) choosing a diffuse type in either surface polishing or reflector would improve DOI resolution but degrade energy resolution; (2) crystal surface finishing with a diffuse polishing combined with a specular reflector appears a favorable candidate with a good balance of DOI and energy resolution; and (3) the linear and logarithm DOI calculation algorithms show overall comparable DOI error, and the linear algorithm was better for photon interactions near the ends of the crystal while the logarithm algorithm was better near the center. These results provide useful guidance in DER DOI detector design in choosing the crystal surface finishing and DOI calculation methods. PMID:26757857
The Surface Finish of Thermally Aged Carbon Fibre Reinforced Composites Using E-glass as a Surface Barrier
NASA Astrophysics Data System (ADS)
de Souza, M. L.; Fox, B. L.
This work investigated the effect of woven E-glass mass (25 g/m2, 50 g/m2, 85 g/m2, 135 g/m2) on the painted surface finish of various thermoset (EPIKOTETM RIM935, EPIKOTETM 04434, Ultratec LpTM ES300, Ultratec LpTM SPV6035) carbon fibre composite laminates, before and after aging at 95 °C for 168 h. The as-moulded laminate surfaces were evaluated using surface profilometry techniques and the painted and aged surfaces were evaluated using a wave-scan distinctness of image (DOI) instrument. It was found that the 25 g/m2 E-glass surface layer assisted with reducing the roughness of the as-moulded surfaces and the long-term waviness of the painted surfaces due to the increase in resin-richness at the surface. The EPIKOTETM 04434 resin system that contained diglycidyl ether of bisphenol F (DGEBF) epoxy had the least change in long-term waviness with thermal aging due to the rigid fluorene-based backbone in comparison to the diglycidyl ether of bisphenol A (DGEBA) systems.
Corrosion Behavior of Titanate Ceramics in Short-Term MCC-1 Tests: The Effects of Surface Finish
Bakel, A.J.; Basco, J.K.; Nole, M.K.; Chamberlain, D.B.
Two series of MCC-1 tests were designed and conducted to describe the effects of surface finish on the corrosion behavior of titanate ceramics. These effects are important for the comparison of short-term test results from different laboratories. Test samples were prepared with 240- and 600-grit finishes. Tests, conducted for 1, 3, 7, and 14 days at 90 C, were carried out in Teflon{reg_sign} vessels. Two different ceramics were used in this study: a Hf-Ce-Ce ceramic containing pyrochlore, perovskite, rutile and a small amount of a silicate phase, and a Hf-Ce-U ceramic containing pyrochlore and rutile. This study shows no detectable difference in the results of tests with ceramics finished to 240-grit and 600-grit; therefore, tests conducted at these two surface finishes can be directly compared. Due to its broader use, we recommend that short-term tests be conducted with monoliths finished to 600-grit. Comparison of data from blank tests in Teflon{reg_sign} and stainless steel vessels shows that the background associated with Teflon{reg_sign} vessels is lower. Therefore, we recommend that short-term tests be conducted in Teflon{reg_sign} vessels.
Coating and surface finishing definition for the Solar Orbiter/METIS inverted external occulter
NASA Astrophysics Data System (ADS)
Landini, Federico; Romoli, Marco; Vives, Sebastien; Baccani, Cristian; Escolle, Clement; Pancrazzi, Maurizio; Focardi, Mauro; Da Deppo, Vania; Moses, John D.; Fineschi, Silvano
The METIS coronagraph aboard the Solar Orbiter mission will undergo extreme environmental conditions (e.g., a thermal excursion of about 350 degrees throughout the various mission phases), due to the peculiar spacecraft trajectory that will reach a perihelion of 0.28 AUs. METIS is characterized by an innovative design for the occultation system that allows to halve the thermal load inside the instrument while guaranteeing the stray light reduction that is required for a solar coronagraph. The Inverted External Occulter (IEO) concept revolutionizes the classical scheme, by exchanging the usual positions of the entrance aperture (that is now the outermost element of the instrument facing the Sun) with the actual occulter (that is a spherical mirror inside the coronagraph boom). The chosen material for the IEO manufacturing is Titanium, as a trade o_ between light weight, strength and low thermal expansion coefficient. A 2 years long test campaign has been run to define the IEO geometry, and its results are addressed in previous dedicated papers. This work describes the results of a further campaign aimed at defining the IEO surface and edge finishing, the support flange geometry and the Titanium coating. Various edge finishing were installed on a prototype of the instrument occulting system and their performance in stray light reduction were compared. The support flange geometry was designed in order to reduce the overall weight, to control the thermal load and to accentuate its stray light suppression performance. The coating is a particularly delicate issue. A black coating is necessary in order to assess the stray light issues, typically critical for visible coronagraphs. Black coating of Titanium is not a standard process, thus several space qualified black coatings were experimented on Titanium and characterized. The impact of the IEO coatings was evaluated, the reflectivity and the BRDFs were measured and are addressed in the paper.
Leg lesions and cleanliness of finishing bulls kept in housing systems with different lying area surfaces.
Schulze Westerath, H; Gygax, L; Mayer, C; Wechsler, B
The influence of the quality of different lying surfaces on lesions and swellings at the joints as well as on the cleanliness of finishing bulls throughout the fattening period was studied. On 17 farms (623 bulls), pens with fully slatted concrete floors (CONCRETE), with rubber coated slats (RUBBER), with cubicles (CUBICLES, provided with five different types of soft lying mat) and with a littered lying area (STRAW) were compared. Bulls kept on STRAW developed the smallest lesion scores at the joints. In CUBICLES, there was a huge variability in the lesion scores depending on the type of lying mat, ranging from values comparable to STRAW up to and greater than the values for CONCRETE. The highest lesion scores at the carpal joints were found on CONCRETE, with intermediate values on RUBBER and in CUBICLES. At the tarsal joints, lesion scores were similar on CONCRETE and RUBBER and in the same range or worse on most mats in the CUBICLES. Swelling scores were highest on CONCRETE and intermediate on RUBBER and in CUBICLES compared to STRAW. In general, there was a steady increase in the lesion scores of the leg joints throughout the fattening period on CONCRETE, RUBBER and STRAW, whereas on some of the mats in CUBICLES these scores were at a high level from early on in the fattening period. Animals in all the housing systems were clean over the whole fattening period. Littering the lying area in CUBICLES affected neither the lesion scores nor the swelling scores at the joints nor animal cleanliness. In conclusion, both rubber coated slats and cubicles provided with soft lying mats were favourable with regard to the levels of lesions and swellings of the leg joints of finishing bulls compared to concrete slats. However, these levels were even lower in pens with a straw bedded lying area. PMID:16843018
Research of polishing process to control the iron contamination on the magnetorheological finished KDP crystal surface.
Chen, Shaoshan; Li, Shengyi; Peng, Xiaoqiang; Hu, Hao; Tie, Guipeng
A new nonaqueous and abrasive-free magnetorheological finishing (MRF) method is adopted for processing a KDP crystal. MRF polishing is easy to result in the embedding of carbonyl iron (CI) powders; meanwhile, Fe contamination on the KDP crystal surface will affect the laser induced damage threshold seriously. This paper puts forward an appropriate MRF polishing process to avoid the embedding. Polishing results show that the embedding of CI powders can be avoided by controlling the polishing parameters. Furthermore, on the KDP crystal surface, magnetorheological fluids residua inevitably exist after polishing and in which the Fe contamination cannot be removed completely by initial ultrasonic cleaning. To solve this problem, a kind of ion beam figuring (IBF) polishing is introduced to remove the impurity layer. Then the content of Fe element contamination and the depth of impurity elements are measured by time of flight secondary ion mass spectrometry. The measurement results show that there are no CI powders embedding in the MRF polished surface and no Fe contamination after the IBF polishing process, respectively. That verifies the feasibility of MRF polishing-IBF polishing (cleaning) for processing a KDP crystal. PMID:25968216
The influence of finishing/polishing time and cooling system on surface roughness and microhardness of two different types of composite resin restorations
Kaminedi, Raja Rajeswari; Penumatsa, Narendra Varma; Priya, Tulasi; Baroudi, Kusai
Objective: The aim of this study was to evaluate the effect of finishing time and polishing time on surface roughness and microhardness of nanofilled and hybrid resin composites. Materials and Methods: Hundred disk composite specimens from micro hybrid composite and nanohybrid composite were prepared, 50 for each type of composite. The specimens were divided into five groups according to the time of finishing and polishing (immediate, 15 min, 24 h and dry). Composite under the Mylar strip without finishing and polishing was taken as the control group. Surface roughness was measured with environmental scanning electronic microscope (ESEM) and microhardness was determined using Vickers Microhardness Tester. Data collected were statistically analyzed by t-test and one-way analysis of variance (ANOVA) followed by Turkey's post hoc test. Results: Smooth surface with low hardness was obtained for the group under Mylar strip without finishing and polishing. The highest roughness was recorded for delayed finishing and polishing for both composites. Immediate finishing and polishing increased the surface hardness more than that in the control group in both types of composites. Dry finishing reduced the hardness significantly for micro hybrid composite, but resulted in the highest surface hardness for nanofilled composite. Conclusion: Immediate finishing and polishing under coolant resulted in the best surface smoothness and hardness values in micro hybrid composite; however, immediate dry finishing and polishing gave the best smoothness and hardness values in nanohybrid composite. PMID:25558457
Comparison of Roller Burnishing Method with Other Hole Surface Finishing Processes Applied on AISI 304 Austenitic Stainless Steel
NASA Astrophysics Data System (ADS)
Akkurt, Adnan
Component surface quality and selection of the optimum material are the main factors determining the performance of components used in machine manufacturing. The level of hole surface quality can be evaluated by the measurements regarding surface roughness, micro-hardness, and cylindricity. In this study, data had been obtained for different hole drilling methods. The characteristics of materials obtained after applications were compared for different hole-finishing processes to identify best hole drilling method. AISI 304 austenitic stainless steel material was used. Surface finishing of holes were performed using drilling, turning, reaming, grinding, honing, and roller burnishing methods. The results of the study show that the roller burnishing method gives the best results for mechanical, metallurgical properties, and hole surface quality of the material. On the other hand, the worst characteristics were obtained in the drilling method.
Effect of substrate surface finish on the lubrication and failure mechanisms of molybdenum disulfide films
NASA Technical Reports Server (NTRS)
Fusaro, R. L.
An optical microscope was used to study the lubrication and failure mechanisms of rubbed (burnished) MoS2 films applied to three substrate surface finishes - polished, sanded, and sandblasted - as a function of sliding distance. The lubrication mechanism was the plastic flow of thin films of MoS2 between flat plateaus on the rider and on the metallic substrate. If the substrate was rough, flat plateaus were created during 'run-in' and the MoS2 flowed across them. Wear life was extended by increasing surface roughness since valleys in the roughened substrate served as reservoirs for MoS2 and a deposit site for wear debris. In moist air, the failure mechanism was the transformation of metallic-colored MoS2 films to a black, powdery material that was found by X-ray diffraction to consist primarily of alpha-iron and MoO3 powders. In dry argon, the failure mechanism was the gradual depletion of the MoS2 film from the contact region by transverse flow. Analysis of the wear debris on the wear track at failure showed it consisted mainly of alpha-iron and some residual MoS2. No molybdenum oxides were found.
Effect of Substrate Surface Finish on the Lubrication and Failure Mechanisms of Molybdenum Disulfide Films
NASA Technical Reports Server (NTRS)
Fusaro, R. L.
An optical microscope was used to study the lubrication and failure mechanisms of rubbed (burnished) MoS2 films applied to three substrate surface finishes - polished, sanded, and sandblasted - as a function of sliding distance. The lubrication mechanism was the plastic flow of thin films of MoS2 between flat plateaus on the rider and on the metallic substrate. If the substrates were rough, flat plateaus were created during 'run in' and the MoS2 flowed across them. Wear life was extended by increasing surface roughness since valleys in the roughened substrate served as reservoirs for MoS2 and a deposit site for wear debris. In moist air, the failure mechanism was the transformation of metallic colored MoS2 films to a black, powdery material that was found by X ray diffraction to consist primarily of alpha iron and MoO3 powders. In dry argon, the failure mechanism was the gradual depletion of the MoS2 film from the contact region by transverse flow. Analysis of the wear debris on the wear track at failure showed it consisted mainly of alpha iron and some residual MoS2. No molybdenum oxides were found.
The Effect of Surface Finish on Low-Temperature Acetylene-Based Carburization of 316L Austenitic Stainless Steel
NASA Astrophysics Data System (ADS)
Ge, Yindong; Ernst, Frank; Kahn, Harold; Heuer, Arthur H.
We observed a strong influence of surface finish on the efficacy of low-temperature acetylene-based carburization of AISI 316L austenitic stainless steel. Steel coupons were prepared with different surface finishes prior to carburization, from P400 SiC grit paper to 1- µm-diameter-diamond-paste. The samples with the finer surface finish developed a thicker "case" (a carbon-rich hardened surface layer) and a larger surface carbon concentration. Transmission electron microscopy revealed that the differences arose mainly from the nature of the deformation-induced disturbed layer on the steel surface. A thick (>400 nm) disturbed layer consisting of nano-crystalline grains (≈10 nm diameter) inhibits acetylene-based carburization. The experimental observations can be explained by assuming that during machining or coarse polishing, the surface oxide layer is broken up and becomes incorporated into the deformation-induced disturbed layer. The incorporated oxide-rich films retard or completely prevent the ingress of carbon into the stainless steel.
Accuracy of digital surface models generated from UAV images
NASA Astrophysics Data System (ADS)
Eltner, Anette; Zenker, Albrecht
The interest in unmanned aerial vehicles (UAV) as a common survey and monitoring technology in geosciences is growing. Progress in digital photogrammetry and computer vision enables fast and precise creation of digital surface models (DSM). Measuring soil erosion with DSM derived from overlapping images is one potential application of UAV data. Therefor, the calculation of DSM with high resolution and accuracy is necessary. However, due to the chaotic characteristic of natural surfaces measuring the accuracy of a UAV-DSM is a difficult task. A first comparison of a field plot captured by UAV and terrestrial laser scanning (TLS) allows for qualitative conclusions, but probable errors within the TLS-DSM (e.g. due to low incidence angles) impede comprised quantitative accuracy information. Thus, a millimetre accurate reference field with the size of 35 m² is designed and measured with a total station. DSM of the test area are generated with different cameras - single-lens reflex camera, compact system camera and compact camera - to account for different camera geometries and their performance at automatic image matching and orientation. Furthermore, different software is tested which on the one hand uses structure from motion and on the other hand a combination of methods from photogrammetry and computer vision. Results show accuracies within few millimetres for a simulated flying height of four metres.
3D printed glass: surface finish and bulk properties as a function of the printing process
NASA Astrophysics Data System (ADS)
Klein, Susanne; Avery, Michael P.; Richardson, Robert; Bartlett, Paul; Frei, Regina; Simske, Steven
It is impossible to print glass directly from a melt, layer by layer. Glass is not only very sensitive to temperature gradients between different layers but also to the cooling process. To achieve a glass state the melt, has to be cooled rapidly to avoid crystallization of the material and then annealed to remove cooling induced stress. In 3D-printing of glass the objects are shaped at room temperature and then fired. The material properties of the final objects are crucially dependent on the frit size of the glass powder used during shaping, the chemical formula of the binder and the firing procedure. For frit sizes below 250 μm, we seem to find a constant volume of pores of less than 5%. Decreasing frit size leads to an increase in the number of pores which then leads to an increase of opacity. The two different binders, 2- hydroxyethyl cellulose and carboxymethylcellulose sodium salt, generate very different porosities. The porosity of samples with 2-hydroxyethyl cellulose is similar to frit-only samples, whereas carboxymethylcellulose sodium salt creates a glass foam. The surface finish is determined by the material the glass comes into contact with during firing.
Fatigue performance of metastable β titanium alloys: Effects of microstructure and surface finish
NASA Astrophysics Data System (ADS)
Kocan, Marcin; Wagner, Lothar; Rack, H. J.
This investigation examined the role of microstructure and surface finish on the high cycle fatigue (HCF) performance of TIMETAL LCB (Ti-6.8Mo-4.5Fe-1.5Al). The as-received microstructure of LCB consisted of elongated β grains with a semicontinuous grain boundary α layer. In contrast, a fine equiaxed β + spheroidized α LCB microstructure was achieved by hot swaging and solution (recrystallization) anneal. The latter modification of the prior β grain structure, together with the size, morphology, and distribution of the primary α phase, resulted in a significant enhancement in the tensile and HCF properties. Furthermore, prestraining (PS), as would be expected during the fabrication of an automotive coil spring, and prior to aging for 30 min at temperatures between 500 and 550 °C, led to additional increases in tensile strength. In contrast, the HCF performance was always reduced when PS prior to aging was included in the overall processing procedure. Finally, shot-peening and roller-burnishing both resulted in an increased fatigue life in the finite life regimen; however, significant reductions in the 107 cycle fatigue strengths were observed when these procedures were used. These observations have been explained by including the effect of process-induced residual tensile stresses in the fatigue analysis, resulting in subsurface fatigue crack nucleation.
An Overview of Surface Finishes and Their Role in Printed Circuit Board Solderability and Solder Joint Performance
Vianco, P.T.
A overview has been presented on the topic of alternative surface finishes for package I/Os and circuit board features. Aspects of processability and solder joint reliability were described for the following coatings: baseline hot-dipped, plated, and plated-and-fused 100Sn and Sn-Pb coatings; Ni/Au; Pd, Ni/Pd, and Ni/Pd/Au finishes; and the recently marketed immersion Ag coatings. The Ni/Au coatings appear to provide the all-around best option in terms of solderability protection and wire bondability. Nickel/Pal ftishes offer a slightly reduced level of performance in these areas that is most likely due to variable Pd surface conditions. It is necessmy to minimize dissolved Au or Pd contents in the solder material to prevent solder joint embrittlement. Ancillary aspects that included thickness measurement techniques; the importance of finish compatibility with conformal coatings and conductive adhesives; and the need for alternative finishes for the processing of non-Pb bearing solders were discussed.
Factors Governing Surface Form Accuracy In Diamond Machined Components
NASA Astrophysics Data System (ADS)
Myler, J. K.; Page, D. A.
Manufacturing methods for diamond machined optical surfaces, for application at infrared wavelengths, require that a new set of criteria must be recognised for the specification of surface form. Appropriate surface form parameters are discussed with particular reference to an XY cartesian geometry CNC machine. Methods for reducing surface form errors in diamond machining are discussed for certain areas such as tool wear, tool centring, and the fixturing of the workpiece. Examples of achievable surface form accuracy are presented. Traditionally, optical surfaces have been produced by use of random polishing techniques using polishing compounds and lapping tools. For lens manufacture, the simplest surface which could be created corresponded to a sphere. The sphere is a natural outcome of a random grinding and polishing process. The measurement of the surface form accuracy would most commonly be performed using a contact test gauge plate, polished to a sphere of known radius of curvature. QA would simply be achieved using a diffuse monochromatic source and looking for residual deviations between the polished surface and the test plate. The specifications governing the manufacture of surfaces using these techniques would call for the accuracy to which the generated surface should match the test plate as defined by a spherical deviations from the required curvature and a non spherical astigmatic error. Consequently, optical design software has tolerancing routines which specifically allow the designer to assess the influence of spherical error and astigmatic error on the optical performance. The creation of general aspheric surfaces is not so straightforward using conventional polishing techniques since the surface profile is non spherical and a good approximation to a power series. For infra red applications (X = 8-12p,m) numerically controlled single point diamond turning is an alternative manufacturing technology capable of creating aspheric profiles as well as
Optical surface pressure measurements: Accuracy and application field evaluation
NASA Astrophysics Data System (ADS)
Bukov, A.; Mosharov, V.; Orlov, A.; Pesetsky, V.; Radchenko, V.; Phonov, S.; Matyash, S.; Kuzmin, M.; Sadovskii, N.
Optical pressure measurement (OPM) is a new pressure measurement method rapidly developed in several aerodynamic research centers: TsAGI (Russia), Boeing, NASA, McDonnell Douglas (all USA), and DLR (Germany). Present level of OPM-method provides its practice as standard experimental method of aerodynamic investigations in definite application fields. Applications of OPM-method are determined mainly by its accuracy. The accuracy of OPM-method is determined by the errors of three following groups: (1) errors of the luminescent pressure sensor (LPS) itself, such as uncompensated temperature influence, photo degradation, temperature and pressure hysteresis, variation of the LPS parameters from point to point on the model surface, etc.; (2) errors of the measurement system, such as noise of the photodetector, nonlinearity and nonuniformity of the photodetector, time and temperature offsets, etc.; and (3) methodological errors, owing to displacement and deformation of the model in an airflow, a contamination of the model surface, scattering of the excitation and luminescent light from the model surface and test section walls, etc. OPM-method allows getting total error of measured pressure not less than 1 percent. This accuracy is enough to visualize the pressure field and allows determining total and distributed aerodynamic loads and solving some problems of local aerodynamic investigations at transonic and supersonic velocities. OPM is less effective at low subsonic velocities (M less than 0.4), and for precise measurements, for example, an airfoil optimization. Current limitations of the OPM-method are discussed on an example of the surface pressure measurements and calculations of the integral loads on the wings of canard-aircraft model. The pressure measurement system and data reduction methods used on these tests are also described.
Effects of Aging Treatment on Mechanical Properties of Sn-58Bi Epoxy Solder on ENEPIG-Surface-Finished PCB
NASA Astrophysics Data System (ADS)
Kim, Jungsoo; Myung, Woo-Ram; Jung, Seung-Boo
The mechanical properties of Sn-58Bi epoxy solder were evaluated by low-speed shear testing as functions of aging time and temperature. To determine the effects of epoxy, the interfacial reaction and mechanical properties of both Sn-58Bi and Sn-58Bi epoxy solder were investigated after aging treatment. The chemical composition and growth kinetics of the intermetallic compound (IMC) formed at the interface between Sn-58Bi solder and electroless nickel electroless palladium immersion gold (ENEPIG) surface finish were analyzed. Sn-58Bi solder paste was applied by stencil-printing on flame retardant-4 substrate, then reflowed. Reflowed samples were aged at 85°C, 95°C, 105°C, and 115°C for up to 1000 h. (Ni,Pd)3Sn4 IMC formed between Sn-58Bi solder and ENEPIG surface finish after reflow. Ni3Sn4 and Ni3P IMCs formed at the interface between (Ni,Pd)3Sn4 IMC and ENEPIG surface finish after aging at 115°C for 300 h. The overall IMC growth rate of Sn-58Bi solder joint was higher than that of Sn-58Bi epoxy solder joint during aging. The shear strength of Sn-58Bi epoxy solder was about 2.4 times higher than that of Sn-58Bi solder due to the blocking effect of epoxy, and the shear strength decreased with increasing aging time.
Laser damage initiation and growth of antireflection coated S-FAP crystal surfaces prepared by pitch lap and magnetorheological finishing
Stolz, C J; Menapace, J A; Schaffers, K I; Bibeau, C; Thomas, M D; Griffin, A J
Antireflection (AR) coatings typically damage at the interface between the substrate and coating. Therefore the substrate finishing technology can have an impact on the laser resistance of the coating. For this study, AR coatings were deposited on Yb:S-FAP [Yb{sup 3+}:Sr{sub 5}(PO{sub 4}){sub 3}F] crystals that received a final polish by both conventional pitch lap finishing as well as magnetorheological finishing (MRF). SEM images of the damage morphology reveals laser damage originates at scratches and at substrate coating interfacial absorbing defects. Previous damage stability tests on multilayer mirror coatings and bare surfaces revealed damage growth can occur at fluences below the initiation fluence. The results from this study suggest the opposite trend for AR coatings. Investigation of unstable HR and uncoated surface damage morphologies reveals significant radial cracking that is not apparent with AR damage due to AR delamination from the coated surface with few apparent cracks at the damage boundary. Damage stability tests show that coated Yb:S-FAP crystals can operate at 1057 nm at fluences around 20 J/cm{sup 2} at 10 ns; almost twice the initiation damage threshold.
Effects of different surface finishing procedures on the change in surface roughness and color of a polymer infiltrated ceramic network material
Arslan, Merve; Türker, Nurullah; Barutcigil, Kubilay
PURPOSE Polymer infiltrated ceramic network (PICN) materials, also called hybrid ceramics, are new materials in dental market. The manufacturer of the PICN material VITA Enamic suggests 3 different finishing procedures for this new material. In the present study, surface roughness and color differences caused from different finishing procedures of VITA Enamic were investigated. MATERIALS AND METHODS 120 specimens were prepared in dimensions 2 × 10 × 12 mm from VITA Enamic hybrid ceramic blocks with 'high translucency' and 'translucency 2M2' shades. The specimens were divided into 8 groups. For each group, different finishing procedures suggested by the manufacturer were performed. Surface roughness values were determined by a tactile portable profilometer. Color changes were evaluated using a clinical spectrophotometer. The data were analyzed using one-way ANOVA and Tukey's post-hoc comparison. The significance level was set at α=0.05. RESULTS The roughest surfaces were observed in Glaze Groups. Their surface roughness values were similar to that of the control group. Clinical Kit and Technical Kit groups did not show a statistically significant difference regarding surface roughness (P>.05). The largest color difference regarding ΔE00 was observed in Clinical Kit finishing groups. There were also statistically significant color changes between the groups (P<.05). However, all the groups showed clinically acceptable color change (ΔE00<2.25) except Clinical Kit Groups (ΔE00>2.25). CONCLUSION Within the limitations of the present study, it may be suggested that finishing the VITA Enamic restorations by Technical Kit instead of Glaze and Clinical Kit gives better clinical performance in regard to surface roughness and shade matching. PMID:26949483
History of magnetorheological finishing
NASA Astrophysics Data System (ADS)
Harris, Daniel C.
Magnetorheological finishing (MRF) is a deterministic method for producing complex optics with figure accuracy <50 nm and surface roughness <1 nm. MRF was invented at the Luikov Institute of Heat and Mass Transfer in Minsk, Belarus in the late 1980s by a team led by William Kordonski. When the Soviet Union opened up, New York businessman Lowell Mintz was invited to Minsk in 1990 to explore possibilities for technology transfer. Mintz was told of the potential for MRF, but did not understand whether it had value. Mintz was referred to Harvey Pollicove at the Center for Optics Manufacturing of the University of Rochester. As a result of their conversation, they sent Prof. Steve Jacobs to visit Minsk and evaluate MRF. From Jacobs' positive findings, and with support from Lowell Mintz, Kordonski and his colleagues were invited in 1993 to work at the Center for Optics Manufacturing with Jacobs and Don Golini to refine MRF technology. A "preprototype" finishing machine was operating by 1994. Prof. Greg Forbes and doctoral student Paul Dumas developed algorithms for deterministic control of MRF. In 1996, Golini recognized the commercial potential of MRF, secured investment capital from Lowell Mintz, and founded QED Technologies. The first commercial MRF machine was unveiled in 1998. It was followed by more advanced models and by groundbreaking subaperture stitching interferometers for metrology. In 2006, QED was acquired by and became a division of Cabot Microelectronics. This paper recounts the history of the development of MRF and the founding of QED Technologies.
Improved accuracy of the remote sensing of sea surface temperature
NASA Technical Reports Server (NTRS)
Dalu, G.; Prabhakara, C.; Lo, R. C.
A method is described for determining the water vapor content to within + or - 0.4 g/sq cm from remotely sensed radiances in three infrared channels, 11, 13, 18 microns. Using this method, it is possible to significantly improve the accuracy of sea surface temperature (SST) over what is obtainable with the two channel technique. A radiative computational scheme for the radiative transfer equation is used to study the manner in which the equivalent radiative temperature of the atmosphere changes as a function of wave number for different atmospheric conditions. Average climatological conditions are used to simulate the radiative response of the atmosphere. This radiative transfer simulation is used to compute brightness temperatures for radiosonde profiles obtained from oceanographic ships, which temperatures are in turn used to estimate the SST. Nimbus 4 IRIS spectral measurements corresponding to the profiles were used in the same way for purposes of comparison.
Experimental evaluation of inlet turbulence, wall boundary layer, surface finish, and fillet radius on small axial turbine state performance
NASA Technical Reports Server (NTRS)
Kozak, A. A.; Brockett, W. D.; Haas, J. E.
The results of an experimental investigation are presented which establish the effects of surface finish, fillet radius, inlet boundary layer thickness, and free-stream inlet turbulence level on the aerodynamic performance of a small axial flow turbine stator. The principal objective was to help understand why large turbine efficiency is not maintained when a large turbine is scaled to a smaller size and to provide the turbine designer with the performance compromises expected for a small scale design. A comprehensive test matrix was used to gain an understanding of the effects of each variable over the full range of all the other variables.
Investigation Into the Accuracy of 3D Surface Roughness Characteristics
NASA Astrophysics Data System (ADS)
Kumermanis, M.; Rudzitis, J.; Mozga, N.; Ancans, A.; Grislis, A.
The existing standards for surface roughness cover only two dimensions, while in reality this is three-dimensional (3D). In particular, the 3D surface roughness parameters are important for solving the contact surface mechanics problems as related to the accuracy of 3D surface roughness characteristics. One of the most important factors for determination of 3D characteristics is the number of data points (NDP) on the x- and y-axes (i.e. in cut-off length). The NDP has a profound effect on the accuracy of measurement results, measuring time and volume of the output data (especially along the y-axis, where the NDP is identical to the number of parallel profiles). At a too small NDP the results will be incorrect and with too broad scatter, while a too large NDP - though not enlarging the range of basic information - considerably increases the measuring time. Therefore, the aim of the work was to find the optimal NDP for such surface processing methods as grinding, spark erosion and shot methods of surface treatment. Eksistējošie virsmas raupjuma standarti apskata virsmas raupjumu tikai divās dimensijās. Tomēr reālais virsmas raupjums pēc savas dabas ir trīsdimensiju (3D) objekts. Līdz ar to virsmas raupjums ir jāraksturo ar 3D parametriem. Un no šo parametru noteikšanas precizitātes ir atkarīgi tālākie virsmas aprēķini, piemēram, virsmu kontaktēšanās process. Viens no svarīgākajiem faktoriem, raksturojot virsmas raupjumu 3D, pielietojot kontakta tipa mēriekārtas, ir datu punktu skaits pa abām mērīšanas asīm x un y. Ar datu punktu skaitu mēs saprotam to skaitu mērīšanas bāzes garumā. Datu punktu skaits būtiski ietekmē sagaidāmo mērījumu rezultātu precizitāti, mērīšanai nepieciešamo laiku un izejas datu faila izmērus (sevišķi y-ass virzienā, kur katrs datu punkts ir paralēls profils). Datu punktu skaitam ir jābūt optimālam. Pārāk mazs punktu skaits noved pie neprecīziem rezultātiem un lielas to izkliedes, savuk
Evaluation of the Effect of Surface Finish on High-Cycle Fatigue of SLM-IN718
NASA Technical Reports Server (NTRS)
Lambert, D. M.
The surface finish of parts produced by additive manufacturing processes is much rougher than the surface finish generated by machining processes, and a rougher surface can reduce the fatigue strength of a part. This paper discusses an effort to quantify that reduction of strength in high-cycle fatigue for selective laser melt (SLM) coupons. A high-cycle fatigue (HCF) knockdown factor was estimated for Inconel 718, manufactured with the SLM process. This factor is the percentage reduction from the maximum stress in fatigue for low-stress ground (LSG) specimens to the maximum stress of those left with the original surface condition at the same fatigue life. Specimens were provided by a number of vendors, free to use their "best practice"; only one heat treat condition was considered; and several test temperatures were characterized, including room temperature, 800F, 1000F, and 1200F. The 1000F data had a large variance, and was omitted from consideration in this document. A first method used linear approximations extracted from the graphs, and only where data was available for both. A recommended knockdown factor of the as-built surface condition (average roughness of approximately 245 micro-inches/inch) versus low-stress ground condition (roughness no more than 4 micro-inches/inch) was established at approximately 1/3 or 33%. This is to say that for the as-built surface condition, a maximum stress of 2/3 of the stress for LSG can be expected to produce a similar life in the as-built surface condition. In this first evaluation, the knockdown factor did not appear to be a function of temperature. A second approach, the "KP method", incorporated the surface finish measure into a new parameter termed the pseudo-stress intensity factor, Kp, which was formulated to be similar to the fracture mechanics stress intensity factor. Using Kp, the variance seemed to be reduced across all sources, and knockdown factors were estimated using Kp over the range where data occurred. A
Surface accuracy measurement sensor test on a 50-meter antenna surface model
NASA Technical Reports Server (NTRS)
Spiers, R. B.; Burcher, E. E.; Stump, C. W.; Saunders, C. G.; Brooks, G. F.
The Surface Accuracy Measurement Sensor (SAMS) is a telescope with a focal plane photo electric detector that senses the lateral position of light source targets in its field of view. After extensive laboratory testing the engineering breadboard sensor system was installed and tested on a 30 degree segment of a 50-meter diameter, mesh surface, antenna model. Test results correlated well with the laboratory tests and indicated accuracies of approximately 0.59 arc seconds at 21 meters range. Test results are presented and recommendations given for sensor improvements.
Characterization of load bearing metrological parameters in reptilian exuviae in comparison to precision-finished cylinder liner surfaces
NASA Astrophysics Data System (ADS)
Abdel-Aal, H. A.; El Mansori, M.
Design of precise functional surfaces is essential for many future applications. In the technological realm, the accumulated experience with construction of such surfaces is not sufficient. Nature provides many examples of dynamic surfaces worthy of study and adoption, at least in concept, within human engineering. This work probes the load-bearing metrological features of the ventral skin in snakes. We examine the structure of two snake species that mainly move by rectilinear locomotion. These are Python regius (Pythonidae) and Bitis gabonica (Vipridae). To this end, we focus on the load-bearing characteristics of the ventral skin surface (i.e., the Sk family of parameters). Therefore, detailed comparison is drawn between the metrological structure of the reptilian surfaces and two sets of technological data. The first set pertains to an actual commercial cylinder liner, whereas the second set is a summary of recommended surface finish metrological values for several commercial cylinder liner manufacturers. The results highlight several similarities between the two types of surfaces. In particular, it is shown that there is a striking correspondence between the sense of texture morphology within both surfaces (although their construction evolved along entirely different paths). It is also shown that reptilian surfaces manifest a high degree of specialization with respect to habitat constraints on wear resistance and adhesive effects. In particular, their surface displays a high degree of pre-conditioning to functional requirements, which eliminates the need for a running-in period.
Compatibility of lead-free solders with lead containing surface finishes as a reliability issue in electronic assemblies
Vianco, P.; Rejent, J.; Artaki, I.; Ray, U.; Finley, D.; Jackson, A.
Enhanced performance goals and environmental restrictions have heightened the consideration for use of alternative solders as replacements for the traditional tin-lead (Sn-Pb) eutectic and near-eutectic alloys. However, the implementation of non-Pb bearing surface finishes may lag behind solder alloy development. A study was performed which examined the effect(s) of Pb contamination on the performance of Sn-Ag-Bi and Sn-Ag-Cu-Sb lead-free solders by the controlled addition of 63Sn-37Pb solder at levels of 0.5 {minus} 8.0 wt.%. Thermal analysis and ring-in-plug shear strength studies were conducted on bulk solder properties. Circuit board prototype studies centered on the performance of 20I/O SOIC gull wing joints. Both alloys exhibited declines in their melting temperatures with greater Sn-Pb additions. The ring-in-plug shear strength of the Sn-Ag-Cu-Sb solder increased slightly with Sn-Pb levels while the Sn-Ag-Bi alloy experienced a strength loss. The mechanical behavior of the SOIC (Small Outline Integrated Circuit) Sn-Ag-Bi solder joints reproduced the strength levels were insensitive to 10,106 thermal cycles. The Sn-Ag-Cu-Sb solder showed a slight decrease in the gull wing joint strengths that was sensitive to the Pb content of the surface finish.
Specification of the surface figure and finish of optical elements in terms of system performance
Church, E.L.; Takacs, P.Z.
Brookhaven National Laboratory is the site of the National Synchrotron Light Source (NSLS); an electron synchrotron which is an intense source of hard and soft x-rays. Since there are no effective refracting elements for x rays, this radiation must be manipulated and focused by mirrors configured to give high reflectivity. This paper describes methods of predicting the degradation of the performance of a simple imaging system in terms of the statistics of the shape errors of the focusing element, and conversely, of specifying those statistics in terms of requirements on image quality. Results are illustrated for a normal-incidence x-ray mirrors having figure errors plus conventional and/or fractal finish errors.
Drop Reliability of Epoxy-contained Sn-58 wt.%Bi Solder Joint with ENIG and ENEPIG Surface Finish Under Temperature and Humidity Test
NASA Astrophysics Data System (ADS)
Myung, Woo-Ram; Kim, Yongil; Kim, Kyung-Yeol; Jung, Seung-Boo
The influence of two kinds of surface finish, namely electroless nickel immersion gold (ENIG) and electroless nickel electroless palladium immersion gold (ENEPIG), on the interfacial reactions and drop reliability of epoxy-enhanced Sn-58 wt.%Bi solder has been investigated after temperature-humidity storage tests. The chemical composition and morphology of intermetallic compounds (IMCs) were characterized by scanning electron microscopy, energy-dispersive x-ray spectroscopy, and electron probe microanalysis. Also, the mechanical reliability of solder joints was evaluated using board-level drop tests. The Sn-Bi epoxy solder/ENEPIG joint exhibited higher IMC growth rate than the Sn-Bi epoxy solder/ENIG joint. After 500 h at 85°C/85% RH storage condition, new IMCs were formed on the Ni3Sn4 layer in samples with both surface finishes. The results of board-level drop tests showed that the number of drops was higher for the ENIG than the ENEPIG surface finish. Solder joint fracture occurred along the interface between the solder and IMC layer for the ENIG surface finish. However, with the ENEPIG surface finish, the crack propagated between the IMCs.
Drop Reliability of Epoxy-contained Sn-58 wt.%Bi Solder Joint with ENIG and ENEPIG Surface Finish Under Temperature and Humidity Test
NASA Astrophysics Data System (ADS)
Myung, Woo-Ram; Kim, Yongil; Kim, Kyung-Yeol; Jung, Seung-Boo
The influence of two kinds of surface finish, namely electroless nickel immersion gold (ENIG) and electroless nickel electroless palladium immersion gold (ENEPIG), on the interfacial reactions and drop reliability of epoxy-enhanced Sn-58 wt.%Bi solder has been investigated after temperature-humidity storage tests. The chemical composition and morphology of intermetallic compounds (IMCs) were characterized by scanning electron microscopy, energy-dispersive x-ray spectroscopy, and electron probe microanalysis. Also, the mechanical reliability of solder joints was evaluated using board-level drop tests. The Sn-Bi epoxy solder/ENEPIG joint exhibited higher IMC growth rate than the Sn-Bi epoxy solder/ENIG joint. After 500 h at 85°C/85% RH storage condition, new IMCs were formed on the Ni3Sn4 layer in samples with both surface finishes. The results of board-level drop tests showed that the number of drops was higher for the ENIG than the ENEPIG surface finish. Solder joint fracture occurred along the interface between the solder and IMC layer for the ENIG surface finish. However, with the ENEPIG surface finish, the crack propagated between the IMCs.
Surface integrity evolution from main cut mode to finish trim cut mode in W-EDM of shape memory alloy
NASA Astrophysics Data System (ADS)
Liu, J. F.; Li, L.; Guo, Y. B.
Shape memory alloys such as Nitinol are widely used in medical, aerospace, actuator, and machine tool industries. However, Nitinol is a very difficult-to-machine material due to the superelasticity, high ductility, and severe strain-hardening. The machined surface should have tailored micro texture to enhance cell adhesion. This study explores the process capability of W-EDM (DI-water based dielectric) in machining Ni50.8Ti49.2 by one main cut (MC) mode followed by four trim cut (TC) modes. Experimental results show that the 6-sigma distributions of Ra are very different between MC mode and finish TC mode. Thick white layers (2-8 μm) with microcracks in MC mode and very thin white layers (0-2 μm) free of those defects in finish TC mode can be observed. However, microcracks would not propagate into the heat affected zone (HAZ) below the white layer. The microhardness of white layer by TC mode is about 50% higher than that by MC mode. In addition, Ni is the dominant element for the measured microhardness.
Picklex, a proprietary formulation, is an alterantive to conventional metal surface pretreatments and is claimed not to produce waste or lower production or lower performance. A laboratory program was designed to evaluate Picklex in common, large scale, polluting surface finishin...
Effect of surface finishing on early-stage corrosion of a carbon steel studied by electrochemical and atomic force microscope characterizations
NASA Astrophysics Data System (ADS)
Li, Yuan; Cheng, Y. Frank
In this work, the early-stage corrosion of a carbon steel with various surface roughness, which was created by different levels of surface finishing treatment, was characterized by an atomic force microscope and electrochemical measurements. It is found that the resulting surface roughness is at nano-meter scale. As the surface roughness increases, the corrosion activity of the steel is increased. The early-stage corrosion of the steel is featured with two stages of dissolution. While the first stage involves a rapid dissolution and increasing surface roughness of the steel, stage two is in an equilibrium state to have an approximately constant corrosion rate and surface roughness. Generally, the corrosion rate of the steel decreases when the surface finish of the specimen becomes finer. Local preferential corrosion occurs at surface irregularities, resulting in the deepening and widening of the features such as scratches with time.
Effect of Pd Interlayer on Electrochemical Properties of ENIG Surface Finish in 3.5 wt.% NaCl Solution
NASA Astrophysics Data System (ADS)
Nam, N. D.; Bui, Q. V.; Nhan, H. T.; Phuong, D. V.; Bian, M. Z.
The corrosion resistance of a multilayered (NiP-Pd-Au) coating with various thicknesses of palladium (Pd) interlayer deposited on copper by an electroless method was investigated using electrochemical techniques including potentiodynamic polarization and electrochemical impedance spectroscopy. In addition, the surface finish was examined by x-ray diffraction analysis and scanning electron microscopy, and the contact angle of the liquid-solid interface was recorded. The corrosion resistance of the copper substrate was considerably improved by Pd interlayer addition. Increase of the thickness of the Pd interlayer enhanced the performance of the Cu-NiP-Pd-Au coating due to low porosity, high protective efficiency, high charge-transfer resistance, and contact angle. These are attributed to the diffusion of layers in the Cu-NiP-Pd-Au coating acting as a physical barrier layer, leading to the protection provided by the coating.
Quantitative evaluation of the surface finish of high gloss polished tool steels
NASA Astrophysics Data System (ADS)
Rebeggiani, S.; Rosén, B.-G.
Standardized procedures to measure and estimate surface qualities of moulds for injection moulding of plastic components do not exist. Instead, steel producers as well as polishers and mould-users need to rely on master plaques for tactile comparisons and/or their own visual estimations for surface quality controls. This paper presents an overview of various surface evaluation methods of steels, including existing standards and available surface metrology. A new method to evaluate high gloss polished tool steel surfaces, based on a three-dimensional non-contacting measurement technique, is presented. The suggested method is based on defect extraction, and should be useful for both specifications and quality controls. Included defects were found to be quality criteria for polished tool steel surfaces. The surface acceptance levels and defect classification are based on interviews and questionnaires, as well as literature studies and visual estimations of test samples made by experienced polishers.
Effect of Surface Finish on Fatigue Properties at Elevated Temperatures I : Low-carbon N-155 with Grain Size of A.S.T.M. 1
NASA Technical Reports Server (NTRS)
Ferguson, Robert R
Effect of three surface finishes of roughness 4 to 5, 20 to 25, and 70 to 80 micro inches rms on fatigue properties were determined for low-carbon N-155 alloy of grain size A.S.T.M. 1 at temperatures of 80 , 1000, 1350, and 1500 F. The fatigue properties for the various finishes differed appreciably at room temperature; however, after short periods at 1000 F and for all periods investigated at temperatures above 1000 F, the specimen finishes had the same fatigue strength. It was concluded that the primary cause of the difference in room-temperature strength was due to compressive stresses set up in the surface and that at elevated temperatures these compressive stresses were relieved by annealing. Apparently, roughness alone did not significantly affect fatigue strength.
Surface Layer Formation When Finish-Hardening Processing of the Parts by Smoothing
NASA Astrophysics Data System (ADS)
Belyaev, V. N.; Tatarkin, E. Ju
Problems of surface layer formation of the parts, when hydraulic smoothing, are considered in this work. The results of theoretical and pilot studies of smoothing in case of nanocarbons and copper salts introduction into the process liquid are given. The influence dependences of the processing modes on roughness and microhardness of surface layer are defined.
ERIC Educational Resources Information Center
Lengert, Gerald
This manual, a self-study guide for apprentices in the drywall finishing trade in British Columbia, attempts to establish standards for the trade. It tells how to produce a properly taped and filled drywall surface and describes what that surface should look like. The standards emphasize quality work that can be realistically achieved on the job.…
Relevance of roughness parameters of surface finish in precision hard turning.
Jouini, Nabil; Revel, Philippe; Bigerelle, Maxence
Precision hard turning is a process to improve the surface integrity of functional surfaces. Machining experiments are carried out on hardened AISI 52100 bearing steel under dry condition using c-BN cutting tools. A full factorial experimental design is used to characterize the effect of cutting parameters. As surface topography is characterized by numerous roughness parameters, their relative relevance is investigated by statistical indices of performance computed by combining the analysis of variance, discriminant analysis and the bootstrap method. The analysis shows that the profile Length ratio (Lr) and the Roughness average (Ra) are the relevant pair of roughness parameters which best discriminates the effect of cutting parameters and enable the classification of surfaces which cannot be distinguished by one parameter: low profile length ratio Lr (Lr = 100.23%) is clearly distinguished from an irregular surface corresponding to a profile length ratio Lr (Lr = 100.42%), whereas the roughness average Ra values are nearly identical. PMID:23868394
Plasma-deposited fluorocarbon polymer films on titanium for preventing cell adhesion: a surface finishing for temporarily used orthopaedic implants
NASA Astrophysics Data System (ADS)
Finke, B.; Testrich, H.; Rebl, H.; Walschus, U.; Schlosser, M.; Zietz, C.; Staehlke, S.; Nebe, J. B.; Weltmann, K. D.; Meichsner, J.; Polak, M.
The design of a titanium implant surface should ideally support its later application in clinical use. Temporarily used implants have to fulfil requirements different from permanent implants: they should ensure the mechanical stabilization of the bone stock but in trauma surgery they should not be integrated into the bone because they will be removed after fracture healing. Finishing of the implant surface by a plasma-fluorocarbon-polymer (PFP) coating is a possible approach for preventing cell adhesion of osteoblasts. Two different low pressure gas-discharge plasma processes, microwave (MW 2.45 GHz) and capacitively coupled radio frequency (RF 13.56 MHz) plasma, were applied for the deposition of the PFP film using a mixture of the precursor octafluoropropane (C3F8) and hydrogen (H2). The thin films were characterized by x-ray photoelectron spectroscopy, Fourier transform infrared reflection absorption spectroscopy, and water contact angle measurements. Cell culture experiments show that cell adhesion and spreading of MG-63 osteoblasts were clearly reduced or nonexistent on these surfaces, also after 24 h of storage in the cell culture medium. In vivo data demonstrated that the local inflammatory tissue response for the PFP films deposited in MW and RF plasma were comparable to uncoated controls.
Influence of femoral stem surface finish on the apparent static shear strength at the stem-cement interface.
Zhang, H; Brown, L T; Blunt, L A; Barrans, S M
The stem-cement interface has long been implicated in failure of cemented total hip replacement. Much research has been performed to study the factors affecting the bond strength between the femoral stem and the bone cement. The present study aims to further investigate the influence of femoral stem surface finish on the apparent static shear strength at the stem-cement interface through a series of pull out tests, where stainless steel rods are employed to represent the femoral stem. The results demonstrated that there was a general tendency for the apparent static shear strength to be increased with the rise of surface roughness. The polished and glass bead-blasted rods illustrated a slip-stick-slip failure whereas the shot-blasted and grit-blasted rods displayed gross interface failure. Following pull out test, cement transfer films were detected on the polished rods, and there was cement debris adhered to the surface of the grit-blasted rods. Micropores, typically 120 mum in diameter, were prevalent in the cement surface interfaced with the polished rods, and the cement surfaces in contact with the shot-blasted and grit-blasted rods were greatly damaged. There was also evidence of metal debris embedding within the cement mantle originating from the tests of the grit-blasted rods, indicating an extremely strong mechanical interlocking at the interface. In summary, this present research demonstrated that the grit-blasted rods with the highest surface roughness were the best in terms of apparent static shear strength. However, it seemed to be most applicable only to the stem designs in which mechanical interlocking of the stem in the initial fixed position was essential. PMID:19627775
Evaluation of the Effect of Surface Finish on High-Cycle Fatigue for SLM-IN718
NASA Technical Reports Server (NTRS)
Lambert, Dennis M.
A high-cycle fatigue (HCF) knockdown factor was estimated for Inconel 718, manufactured with the selective laser melt (SLM) process. This factor is the reduction at a common fatigue life from the maximum stress in fatigue for low-stress ground (LSG) specimens to the maximum stress of those left with the original surface condition. Various vendors provided specimens. To reduce the number of degrees-of-freedom, only one heat treat condition was evaluated. Testing temperatures included room temperature, 800F, 1000F, and 1200F. The two surface conditions were compared at constant lives, where data was available. The recommended knockdown factor of the as-built surface condition (average roughness of approximately 245 micro-inches/inch) versus low-stress ground condition (roughness <= 4 micro-inches/inch) is approximately 1/3 or 33%. This is to say that for the as-built surface condition, a maximum stress of 2/3 of the stress for LSG can be expected to produce the same life in the as built surface condition. As an alternative method, the surface finish was incorporated into a new parameter with the maximum stress. The new parameter was formulated to be similar to the fracture mechanics stress intensity factor, and it was named the pseudo stress intensity factor, Kp. Using Kp, the variance seemed acceptable across all sources, and the knockdown factor was estimated over the range of data identified by Kp where data occurred. A plot of the results suggests that the knockdown factor is a function of temperature, and that for low lives the knockdown is greater than the knockdown observed above about one million cycles, where it stabilizes. One data point at room temperature was clearly different, and the sparsity of data in the higher life region reduces the value of these results. The method does appear to provide useful results, and further characterization of the method is suggested.
Accuracy of functional surfaces on comparatively modeled protein structures
Zhao, Jieling; Dundas, Joe; Kachalo, Sema; Ouyang, Zheng; Liang, Jie
Identification and characterization of protein functional surfaces are important for predicting protein function, understanding enzyme mechanism, and docking small compounds to proteins. As the rapid speed of accumulation of protein sequence information far exceeds that of structures, constructing accurate models of protein functional surfaces and identify their key elements become increasingly important. A promising approach is to build comparative models from sequences using known structural templates such as those obtained from structural genome projects. Here we assess how well this approach works in modeling binding surfaces. By systematically building three-dimensional comparative models of proteins using Modeller, we determine how well functional surfaces can be accurately reproduced. We use an alpha shape based pocket algorithm to compute all pockets on the modeled structures, and conduct a large-scale computation of similarity measurements (pocket RMSD and fraction of functional atoms captured) for 26,590 modeled enzyme protein structures. Overall, we find that when the sequence fragment of the binding surfaces has more than 45% identity to that of the tempalte protein, the modeled surfaces have on average an RMSD of 0.5 Å, and contain 48% or more of the binding surface atoms, with nearly all of the important atoms in the signatures of binding pockets captured. PMID:21541664
NASA Astrophysics Data System (ADS)
Riendeau, Diane
As we finish this publishing cycle, I'd like to thank all the readers who sent in video clips. If you have a YouTube clip that you use in class, please send the link and a brief description to firstname.lastname@example.com.
Surface finish quality of the outer AXAF mirror pair based on X-ray measurements of the VETA-I
NASA Technical Reports Server (NTRS)
Hughes, John P.; Schwartz, Daniel; Szentgyorgyi, Andrew; Van Speybroeck, Leon; Zhao, Ping
We employ the X-ray measurements of the VETA-I taken at the X-Ray Calibration Facility (XRCF) of the Marshall Space Flight Center (MSFC) to extract information about the surface finish quality of the outermost pair of AXAF mirrors. The particular measurements we consider are 1D scans of the core of the point response function (PRF) (FWHM scans), the encircled energy as a function of radius, and 1D scans of the wings of the PRF. We discuss briefly our raytrace model which incorporates the numerous effects present in the VETA-I test, such as the finite source distance, the size and shape of the X-ray source, the residual gravitational distortions of the optic, the despace of the VETA-I, and particulate contamination. We show how the data constrain the amplitude of mirror surface deviations for spatial frequencies greater than about 0.1/mm. Constraints on the average amplitude of circumferential slope errors are derived as well.
Surface finish quality of the outer AXAF mirror pair based on x ray measurements of the VETA-I
NASA Technical Reports Server (NTRS)
Hughes, John P.; Schwartz, Daniel A.; Szentgyorgyi, Andrew; Vanspeybroeck, Leon; Zhao, Ping
We employ the X-ray measurements of the VETA-I taken at the X-Ray Calibration Facility (XRCF) of the Marshall Space Flight Center (MSFC) to extract information about the surface finish quality of the outermost pair of AXAF mirrors. The particular measurements we consider are one dimensional scans of the core of the point response function (PRF) (full width half maximum (FWHM) scans), the encircled energy as a function of radius, and one dimensional scans of the wings of the PRF. We discuss briefly our ray trace model which incorporates the numerous effects present in the VETA-I test, such as the finite source distance, the size and shape of the X-ray source, the residual gravitational distortions of the optic, the despace of the VETA-I, and particulate contamination. We show how the data constrain the amplitude of mirror surface deviations for spatial frequencies greater than about 0.1 mm(exp -1). Constraints on the average amplitude of circumferential slope errors are derived as well.
The pH effect on black spots in surface finish: Electroless nickel immersion gold
NASA Astrophysics Data System (ADS)
Won, Yong Sun; Park, Sung Soo; Lee, Jinuk; Kim, Jong-Yun; Lee, Seong-Jae
In order to understand the black spot generation after electroless nickel immersion gold (ENIG) plating, we investigated the pH effect with a combined approach of experiments and computer aided engineering (CAE). As the pH is increased in IG plating solution, the deprotonation of citric acid as chelating agent is enhanced to stabilize the solution by producing Ni-citrate complex ion. For the substitution reaction between nickel and gold, excess citrate ions (deprotonated citric acids) are adsorbed along nodal boundaries of Ni-P layer to decrease the surface reactivity. Since the low reactivity decreases the overall growth rate, the resulting homogeneous Au layer growth avoids the unfavorable galvanic cell corrosion to control black spot. Based on molecular orbital method and kinetic Monte Carlo calculation, our computational approach well explained the capability of citric acid as chelating agent and the Au growth rate along the nodal boundaries of Ni-P layer depending on the surface reactivity.
Space processing applications of ion beam technology. [surface finishing, welding, milling and film deposition
NASA Technical Reports Server (NTRS)
Grodzka, P. G.
Ion thruster engines for spacecraft propulsion can serve as ion beam sources for potential space processing applications. The advantages of space vacuum environments and the possible gravity effects on thruster ion beam materials operations such as thin film growth, ion milling, and surface texturing were investigated. The direct gravity effect on sputter deposition and vapor deposition processes are discussed as well as techniques for cold and warm welding.
NCMS PWB program report surface finishes team task WBS No. 3.1.1: Phase 1, Etching Studies: Chemical etching of copper for improved solderability
Stevenson, J.O.; Guilinger, T.R.; Hosking, F.M.; Yost, F.G.; Sorensen, N.R.
Sandia National Laboratories has established a Cooperative Research and Development Agreement with consortium members of the National Center for Manufacturing Sciences (NCMS) to develop fundamental generic technology in the area of printed wiring board materials and surface finishes. Improved solderability of copper substrates is an important component of the Sandia-NCMS program. We are investigating the effects of surface roughness on the wettability and solderability behavior of several different types of copper board finishes. In this paper, we present roughness and solderability characterizations for a variety of chemically-etched copper substrates. Initial testing on six chemical etches demonstrate that surface roughness can be greatly enhanced through chemical etching. Noticeable improvements in solder wettability were observed to accompany increases in roughness. A number of different algorithms and measures of roughness were used to gain insight into surface morphologies that lead to improved solderability.
Optimizing surface finishing processes through the use of novel solvents and systems
NASA Astrophysics Data System (ADS)
Quillen, M.; Holbrook, P.; Moore, J.
As the semiconductor industry continues to implement the ITRS (International Technology Roadmap for Semiconductors) node targets that go beyond 45nm [1], the need for improved cleanliness between repeated process steps continues to grow. Wafer cleaning challenges cover many applications such as Cu/low-K integration, where trade-offs must be made between dielectric damage and residue by plasma etching and CMP or moisture uptake by aqueous cleaning products. [2-5] Some surface sensitive processes use the Marangoni tool design [6] where a conventional solvent such as IPA (isopropanol), combines with water to provide improved physical properties such as reduced contact angle and surface tension. This paper introduces the use of alternative solvents and their mixtures compared to pure IPA in removing ionics, moisture, and particles using immersion bench-chemistry models of various processes. A novel Eastman proprietary solvent, Eastman methyl acetate is observed to provide improvement in ionic, moisture capture, and particle removal, as compared to conventional IPA. [7] These benefits may be improved relative to pure IPA, simply by the addition of various additives. Some physical properties of the mixtures were found to be relatively unchanged even as measured performance improved. This report presents our attempts to cite and optimize these benefits through the use of laboratory models.
The purpose of this document is to provide guidance to surface finishing manufacturers, metal finishing decision maker and regulators on management practices and control technologies for managing cyanide in the workplace. This information can benefit key industry stakeholder gro...
Theoretical bases of the surface layer formation in the finishing and hardening treatment of details by SPD in flexible granular environment
NASA Astrophysics Data System (ADS)
Tamarkin, M. A.; Tishchenko, E. E.; Fedorov, V. P.
The article presents results of theoretical studies of the surface layer formation during finishing and hardening treatment of details by SPD in flexible granular environment. The dependencies are fixed for determining the surface roughness, processing time, the depth of the hardened layer and the degree of hardening for different methods of treatment by SPD in flexible granular environment. The process of residual stresses formation is researched.
Solar absorption characteristics of several coatings and surface finishes. [for solar energy collectors
NASA Technical Reports Server (NTRS)
Lowery, J. R.
Solar absorption characteristics are established for several films potentially favorable for use as receiving surfaces in solar energy collectors. Included in the investigation were chemically produced black films, black electrodeposits, and anodized coatings. It was found that black nickel exhibited the best combination of selective optical properties of any of the coatings studied. A serious drawback to black nickel was its high susceptibility to degradation in the presence of high moisture environments. Electroplated black chrome generally exhibited high solar absorptivities, but the emissivity varied considerably and was also relatively high under some conditions. The black chrome had the greatest moisture resistance of any of the coatings tested. Black oxide coatings on copper and steel substrates showed the best combination of selective optical properties of any of the chemical conversion films studied.
Ion beam technology applications study. [ion impact, implantation, and surface finishing
NASA Technical Reports Server (NTRS)
Sellen, J. M., Jr.; Zafran, S.; Komatsu, G. K.
Specific perceptions and possible ion beam technology applications were obtained as a result of a literature search and contact interviews with various institutions and individuals which took place over a 5-month period. The use of broad beam electron bombardment ion sources is assessed for materials deposition, removal, and alteration. Special techniques examined include: (1) cleaning, cutting, and texturing for surface treatment; (2) crosslinking of polymers, stress relief in deposited layers, and the creation of defect states in crystalline material by ion impact; and (3) ion implantation during epitaxial growth and the deposition of neutral materials sputtered by the ion beam. The aspects, advantages, and disadvantages of ion beam technology and the competitive role of alternative technologies are discussed.
Surface Accuracy Measurement Sensor for Deployable Reflector Antennas (SAMS DRA)
NASA Technical Reports Server (NTRS)
Neiswander, R. S.
Specifications, system configurations, and concept tests for surface measurement sensors for deployable reflector antennas are presented. Two approaches toward the optical measurement of remote target displacements are discussed: optical ranging, in which the basic measurement is target-to-sensor range; and in particular, optical angular sensing, in which the principle measurements are of target angular displacements lateral to the line of sight. Four representative space antennas are examined.
Comparative Study of ENIG and ENEPIG as Surface Finishes for a Sn-Ag-Cu Solder Joint
NASA Astrophysics Data System (ADS)
Yoon, Jeong-Won; Noh, Bo-In; Jung, Seung-Boo
Interfacial reactions and joint reliability of Sn-3.0Ag-0.5Cu solder with two different surface finishes, electroless nickel-immersion gold (ENIG) and electroless nickel-electroless palladium-immersion gold (ENEPIG), were evaluated during a reflow process. We first compared the interfacial reactions of the two solder joints and also successfully revealed a connection between the interfacial reaction behavior and mechanical reliability. The Sn-Ag-Cu/ENIG joint exhibited a higher intermetallic compound (IMC) growth rate and a higher consumption rate of the Ni(P) layer than the Sn-Ag-Cu/ENEPIG joint. The presence of the Pd layer in the ENEPIG suppressed the growth of the interfacial IMC layer and the consumption of the Ni(P) layer, resulting in the superior interfacial stability of the solder joint. The shear test results show that the ENIG joint fractured along the interface, exhibiting indications of brittle failure possibly due to the brittle IMC layer. In contrast, the failure of the ENEPIG joint only went through the bulk solder, supporting the idea that the interface is mechanically reliable. The results from this study confirm that the Sn-Ag-Cu/ENEPIG solder joint is mechanically robust and, thus, the combination is a viable option for a Pb-free package system.
Experimental Investigation of the Heat-Transfer Rate to a Series of 20 deg Cones of Various Surface Finishes at a Mach Number of 4.95
NASA Technical Reports Server (NTRS)
Jones, Jim J.
The heat-transfer rates were measured on a series of cones of various surface finishes at a Mach number of 4.95 and Reynolds numbers per foot varying from 20 x 10(exp 6) to 100 x 10(exp 6). The range of surface finish was from a very smooth polish to smooth machining with no polish (65 micro inches rms). Some laminar boundary-layer data were obtained, since transition was not artificially tripped. Emphasis, however, is centered on the turbulent boundary layer. The results indicated that the turbulent heat-transfer rate for the highest roughness tested was only slightly greater than that for the smoothest surface. The laminar-sublayer thickness was calculated to be about half the roughness height for the roughest model at the highest value of unit Reynolds number tested.
Deterministic precision finishing of domes and conformal optics
NASA Astrophysics Data System (ADS)
Shorey, Aric; Kordonski, William; Tricard, Marc
In order to enhance missile performance, future window and dome designs will incorporate shapes with improved aerodynamic performance compared with the more traditional flats and spheres. Due to their constantly changing curvature and steep slopes, these shapes are incompatible with most conventional polishing and metrology solutions. Two types of a novel polishing technology, Magnetorheological Finishing (MRF®) and Magnetorheological (MR) Jet, could enable cost-effective manufacturing of free-form optical surfaces. MRF, a deterministic sub-aperture magnetically assisted polishing method, has been developed to overcome many of the fundamental limitations of traditional finishing. MRF has demonstrated the ability to produce complex optical surfaces with accuracies better than 30 nm peak-to-valley (PV) and surface micro-roughness less than 1 nm rms on a wide variety of optical glasses, single crystals, and glass-ceramics. The polishing tool in MRF perfectly conforms to the optical surface making it well suited for finishing this class of optics. A newly developed magnetically assisted finishing method MR JetTM, addresses the challenge of finishing the inside of steep concave domes and other irregular shapes. An applied magnetic field coupled with the properties of the MR fluid allow for stable removal rate with stand-off distances of tens of centimeters. Surface figure and roughness values similar to traditional MRF have been demonstrated. Combining these technologies with metrology techniques, such as Sub-aperture Stitching Interferometer (SSI®) and Asphere Stitching Interferometer (ASI®), enable higher precision finishing of the windows and domes today, as well as the finishing of future conformal designs.
Effects of a range of machined and ground surface finishes on the simulated reactor helium corrosion of several candidate structural materials. [Inconel MA 754
Thompson, L.D.
This report discusses the corrosion behavior of several candidate reactor structural alloys in a simulated advanced high-temperature gas-cooled reactor (HTGR) environment over a range of lathe-machined and centerless-ground surface finishes. The helium environment contained 50 Pa H/sub 2//5 Pa CO/5 Pa CH/sub 4//<0.05 Pa H/sub 2/O (500 ..mu..atm H/sub 2//50 ..mu..atm CO/50 ..mu..atm CH/sub 4//<0.5 ..mu..atm H/sub 2/O) at 900/sup 0/C for a total exposure of 3000 h. The test alloys included two vacuum-cast superalloys (IN 100 and IN 713LC); a centrifugally cast austenitic alloy (HK 40); three wrought high-temperature alloys (Alloy 800H, Hastelloy X, and Inconel 617); and a nickel-base oxide-dispersion-strengthened alloy (Inconel MA 754). Surface finish variations did not affect the simulated advanced-HTGR corrosion behavior of these materials. Under these conditions, the availability of reactant gaseous impurities controls the kinetics of the observed gas-metal interactions. Variations in the near-surface activities and mobilities of reactive solute elements, such as chromium, which might be expected to be affected by changes in surface finish, do not seem to greatly influence corrosion in this simulated advanced HTGR environment. 18 figures, 4 tables.
Code of Federal Regulations, 2010 CFR
... 7 Agriculture 2 2010-01-01 2010-01-01 false Finish. 29.2518 Section 29.2518 Agriculture...-Cured Tobacco (u.s. Types 22, 23, and Foreign Type 96) § 29.2518 Finish. The reflectance factor in color perception. Finish indicates the sheen or shine of the surface of a tobacco leaf. (See chart, § 29.2601.)...
Code of Federal Regulations, 2010 CFR
... 7 Agriculture 2 2010-01-01 2010-01-01 false Finish. 29.2268 Section 29.2268 Agriculture... INSPECTION Standards Official Standard Grades for Virginia Fire-Cured Tobacco (u.s. Type 21) § 29.2268 Finish. The reflectance factor in color perception. Finish indicates the sheen or shine of the surface of...
Code of Federal Regulations, 2010 CFR
... 7 Agriculture 2 2010-01-01 2010-01-01 false Finish. 29.3022 Section 29.3022 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Finish. The reflectance factor in color perception. Finish indicates the sheen or shine of the surface...
A broad overview of the metal finishing processes in pollution prevention. The volume of hazardous/toxic waste streams produced from metal finishing operations is significant. It is common for product surfaces to undergo more than 10 finishing steps. The elimination of any of ...
Concentration Data for Anthropogenic Organic Compounds in Ground Water, Surface Water, and Finished Water of Selected Community Water Systems in the United States, 2002-05
Carter, Janet M.; Delzer, Gregory C.; Kingsbury, James A.; Hopple, Jessica A.
The National Water-Quality Assessment Program of the U.S. Geological Survey began implementing Source Water-Quality Assessments (SWQAs) in 2001 that focus on characterizing the quality of source water and finished water of aquifers and major rivers used by some of the larger community water systems (CWSs) in the United States. As used for SWQA studies, source water is the raw (ambient) water collected at the supply well prior to water treatment (for ground water) or the raw (ambient) water collected from the river near the intake (for surface water), and finished water is the water that is treated and ready to be delivered to consumers. Finished water is collected before entering the distribution system. SWQA studies are conducted in two phases, and the objectives of SWQA studies are twofold: (1) to determine the occurrence and, for rivers, seasonal changes in concentrations of a broad list of anthropogenic organic compounds (AOCs) in aquifers and rivers that have some of the largest withdrawals for drinking-water supply (phase 1), and (2) for those AOCs found to occur most frequently in source water, characterize the extent to which these compounds are present in finished water (phase 2). These objectives were met for SWQA studies by collecting ground-water and surface-water (source) samples and analyzing these samples for 258 AOCs during phase 1. Samples from a subset of wells and surface-water sites located in areas with substantial agricultural production in the watershed were analyzed for 19 additional AOCs, for a total of 277 compounds analyzed for SWQA studies. The 277 compounds were classified according to the following 13 primary use or source groups: (1) disinfection by-products; (2) fumigant-related compounds; (3) fungicides; (4) gasoline hydrocarbons, oxygenates, and oxygenate degradates; (5) herbicides and herbicide degradates; (6) insecticides and insecticide degradates; (7) manufacturing additives; (8) organic synthesis compounds; (9) pavement- and
Study of the effect of tribo-materials and surface finish on the lubricant performance of new halogen-free room temperature ionic liquids
NASA Astrophysics Data System (ADS)
Saurín, N.; Minami, I.; Sanes, J.; Bermúdez, M. D.
The present work evaluates different materials and surface finish in the presence of newly designed, hydrophobic halogen-free room temperature ionic liquids (RTILs) as lubricants. A reciprocating tribo-tester was employed with steel-ceramic and steel-thermosetting epoxy resin contacts under boundary lubrication conditions. Four different tetraalkylphosphonium organosilanesulfonate RTILs provided excellent lubricating performance, with friction coefficients as low as 0.057, and non-measurable wear for the higher roughness machine-finish stainless steel flat against sapphire balls, in the case of the lubricants containing the 2-trimethylsilylethanesulfonate anion. Higher friction coefficients of the order of 0.1 and wear volumes of the order of 10-4 mm3 were observed for the lower roughness fine-finished flat stainless steel surface. All RTILs prevent wear of epoxy resin against stainless steel balls, with friction coefficients in the range of 0.03-0.06. EDX analysis shows the presence of RTILs on the stainless steel surfaces after the tribological tests. Under the experimental conditions, no corrosive processes were observed.
Enamel and Dentin Surface Finishing Influence on the Roughness and Microshear Bond Strength of a Lithium Silicate Glass-Ceramic for Laminate Veneers
Gonzaga, Carla Castiglia; Bravo, Ruth Peggy; Pavelski, Thiago Vinícius; Garcia, Paula Pontes; Correr, Gisele Maria; Leonardi, Denise Piotto; da Cunha, Leonardo Fernandes; Furuse, Adilson Yoshio
Objectives. This study evaluated the influence of cavity surface finishing with diamond burs of different grit mounted on high-speed turbine and ultrasound on the roughness and microshear bond strength (MBS) of a lithium silicate glass-ceramic to enamel and dentin. Methods. Enamel and dentin specimens were divided into seven groups, according to the type of surface finishing: 1200-grit sandpaper (control), two different brands of medium-grit and fine-grit diamond burs in a high-speed turbine; medium-grit and fine-grit CVD (chemical vapor deposition) tips in an ultrasonic device. Roughness parameters (n = 5) and MSBS to a glass-ceramic (n = 10) were determined. Data were analyzed using ANOVA and Tukey's test (α = 5%). Results. Control group showed lower mean roughness readings and groups that used medium-grit diamond burs showed the highest mean roughness values. Regarding MSBS, there was no statistical difference when comparing the groups gritted with the same brand of medium- and fine-grit burs and tips. Conclusions. Cavity surface finishing influenced the roughness parameters and MSBS of a glass-ceramic to enamel and dentin. Medium-grit diamond burs in high-speed turbine showed the highest mean roughness values. Fine-grit CVD tips in ultrasound presented the highest MSBS values for both enamel and dentin. PMID:27347507
Surface Accuracy Analysis of Single Panels for the Shanghai 65-M Radio Telescope
NASA Astrophysics Data System (ADS)
Fu, Li; Liu, Guoxi; Jin, Chao; Yan, Feng; An, Tao; Zhiqiang, Shen
We presented the surface accuracy measurements of 5 single panels of the Shanghai 65-meter radio telescope by employing the coordinate measuring machine and laser tracker. The measurement data obtained from the two instruments were analyzed with the common point transformation and CAD surface fitting techniques, respectively. The derived rms uncertainties of panel accuracy from two methods are consistent with each other, and both match the design specification. The simulations of the effects of manufacturing error, gravity, temperature and wind on the panel surface accuracy with the finite element analysis method suggest that the first two factors account for primary sources of the accuracy uncertainty. The panel deformation under concentrated load was analyzed through finite element analysis and experiment, and the comparison error is 5.6%. There is not plastic deformation when people of weight below 70kg installs and remedies the panel.
Concentration data for anthropogenic organic compounds in groundwater, surface water, and finished water of selected community water systems in the United States, 2002-10
Carter, Janet M.; Kingsbury, James A.; Hopple, Jessica A.; Delzer, Gregory C.
The National Water-Quality Assessment Program of the U.S. Geological Survey began implementing Source Water-Quality Assessments (SWQAs) in 2001 that focus on characterizing the quality of source water and finished water of aquifers and major rivers used by some of the larger community water systems in the United States. As used in SWQA studies, source water is the raw (ambient) water collected at the supply well before water treatment (for groundwater) or the raw (ambient) water collected from the river near the intake (for surface water), and finished water is the water that has been treated and is ready to be delivered to consumers. Finished-water samples are collected before the water enters the distribution system. The primary objective of SWQAs is to determine the occurrence of more than 250 anthropogenic organic compounds in source water used by community water systems, many of which currently are unregulated in drinking water by the U.S. Environmental Protection Agency. A secondary objective is to understand recurrence patterns in source water and determine if these patterns also occur in finished water before distribution. SWQA studies were conducted in two phases for most studies completed by 2005, and in one phase for most studies completed since 2005. Analytical results are reported for a total of 295 different anthropogenic organic compounds monitored in source-water and finished-water samples collected during 2002-10. The 295 compounds were classified according to the following 13 primary use or source groups: (1) disinfection by-products; (2) fumigant-related compounds; (3) fungicides; (4) gasoline hydrocarbons, oxygenates, and oxygenate degradates; (5) herbicides and herbicide degradates; (6) insecticides and insecticide degradates; (7) manufacturing additives; (8) organic synthesis compounds; (9) pavement- and combustion-derived compounds; (10) personal-care and domestic-use products; (11) plant- or animal-derived biochemicals; (12) refrigerants and
Accuracy assessment of a surface electromyogram decomposition system in human first dorsal interosseus muscle
NASA Astrophysics Data System (ADS)
Hu, Xiaogang; Rymer, William Z.; Suresh, Nina L.
Objective. The aim of this study is to assess the accuracy of a surface electromyogram (sEMG) motor unit (MU) decomposition algorithm during low levels of muscle contraction. Approach. A two-source method was used to verify the accuracy of the sEMG decomposition system, by utilizing simultaneous intramuscular and surface EMG recordings from the human first dorsal interosseous muscle recorded during isometric trapezoidal force contractions. Spike trains from each recording type were decomposed independently utilizing two different algorithms, EMGlab and dEMG decomposition algorithms. The degree of agreement of the decomposed spike timings was assessed for three different segments of the EMG signals, corresponding to specified regions in the force task. A regression analysis was performed to examine whether certain properties of the sEMG and force signal can predict the decomposition accuracy. Main results. The average accuracy of successful decomposition among the 119 MUs that were common to both intramuscular and surface records was approximately 95%, and the accuracy was comparable between the different segments of the sEMG signals (i.e., force ramp-up versus steady state force versus combined). The regression function between the accuracy and properties of sEMG and force signals revealed that the signal-to-noise ratio of the action potential and stability in the action potential records were significant predictors of the surface decomposition accuracy. Significance. The outcomes of our study confirm the accuracy of the sEMG decomposition algorithm during low muscle contraction levels and provide confidence in the overall validity of the surface dEMG decomposition algorithm.
Microstructural characterization of diamond-turned aluminum substrates of memory disks: effects of inclusions on the surface finish and tool wear
Syn, C.K.
Diamond-turned substrates of computer memory disks of Al-Mg alloys of 5086 and 5186 grades and a worn diamond tool usd in machining 5086 alloy were examined by means of optical and scanning electron microscopy. Detailed analysis of the examination results showed that the undesirable ''orange peel'' finish and accelerated tool wear that occurred in machining 5086 grade alloy disks could be traced to high inclusion content in the material. The iron-containing inclusion particles were shown to be detrimental to the tool life since they could chemically react with the tool material and induce machine tool chatter. The tool wear induced by the inclusion particles then contributed to the ''orange peel'' finish by creating an unevenly cut, rough surface on the disks.
Uav Aerial Survey: Accuracy Estimation for Automatically Generated Dense Digital Surface Model and Orthothoto Plan
NASA Astrophysics Data System (ADS)
Altyntsev, M. A.; Arbuzov, S. A.; Popov, R. A.; Tsoi, G. V.; Gromov, M. O.
A dense digital surface model is one of the products generated by using UAV aerial survey data. Today more and more specialized software are supplied with modules for generating such kind of models. The procedure for dense digital model generation can be completely or partly automated. Due to the lack of reliable criterion of accuracy estimation it is rather complicated to judge the generation validity of such models. One of such criterion can be mobile laser scanning data as a source for the detailed accuracy estimation of the dense digital surface model generation. These data may be also used to estimate the accuracy of digital orthophoto plans created by using UAV aerial survey data. The results of accuracy estimation for both kinds of products are presented in the paper.
Computer-aided high-accuracy testing of reflective surface with reverse Hartmann test.
Wang, Daodang; Zhang, Sen; Wu, Rengmao; Huang, Chih Yu; Cheng, Hsiang-Nan; Liang, Rongguang
The deflectometry provides a feasible way for surface testing with a high dynamic range, and the calibration is a key issue in the testing. A computer-aided testing method based on reverse Hartmann test, a fringe-illumination deflectometry, is proposed for high-accuracy testing of reflective surfaces. The virtual "null" testing of surface error is achieved based on ray tracing of the modeled test system. Due to the off-axis configuration in the test system, it places ultra-high requirement on the calibration of system geometry. The system modeling error can introduce significant residual systematic error in the testing results, especially in the cases of convex surface and small working distance. A calibration method based on the computer-aided reverse optimization with iterative ray tracing is proposed for the high-accuracy testing of reflective surface. Both the computer simulation and experiments have been carried out to demonstrate the feasibility of the proposed measurement method, and good measurement accuracy has been achieved. The proposed method can achieve the measurement accuracy comparable to the interferometric method, even with the large system geometry calibration error, providing a feasible way to address the uncertainty on the calibration of system geometry. PMID:27557245
Synthetic rubber surface as an alternative to concrete to improve welfare and performance of finishing beef cattle reared on fully slatted flooring.
Brscic, M; Ricci, R; Prevedello, P; Lonardi, C; De Nardi, R; Contiero, B; Gottardo, F; Cozzi, G
The aim of this study was to compare a fully slatted concrete floor (concrete slatted (CS)) with the same floor on which synthetic rubber slats were placed on the concrete slats (rubber slatted (RS)) as housing solution for finishing beef cattle. The present study involved five commercial beef cattle farms in which the floor of at least three pens was kept as fully slatted, and in an equal number of pens a rubber cover was placed on the floor, tightly matching the gap profile of the concrete slats to allow the drainage of manure. A total of 326 finishing beef bulls were used (153 on CS and 173 on RS), and regardless of the floor treatment animals were housed in groups of 6 to 12 bulls/pen with a space allowance of 3.1 ± 0.2 m2/bull. Bulls had similar initial live weights (422.3 kg on CS and 425.0 kg on RS), but bulls on RS were heavier at the end of the finishing period with a higher average daily gain than bulls kept on CS (1.53 v. 1.46 kg/day; P<0.05). The proportion of bulls treated for locomotor problems was lower in RS pens compared with CS. Rubber covering prevented the occurrence of bursitis, but it increased the odds for hoof overgrowth at end of the finishing period. Hoof overgrowth detected in vivo in bulls on RS was confirmed at the slaughterhouse by the longer dorsal wall and diagonal lengths of the hoof as well as by a more acute toe angle. Compared with bulls on CS, bulls on RS showed less inactivity and resting time, increased social interactions, decreased abnormal lying down and unsuccessful attempts to lie down, as well as shortened the time for lying down. Bulls in RS pens were dirtier compared with those in CS pens, likely due to the draining gaps being reduced to 11.6 ± 1.2% of the total pen surface compared with the 16.9 ± 1.7% in CS pens. This study gave further evidence about the positive effects of the RS floor on growth performance and welfare of finishing beef cattle, although compromising cleanliness and hoof overgrowth. PMID:26190252
Assessment of the influence of surface finishing and weld joints on the corrosion/oxidation behaviour of stainless steels in lead bismuth eutectic
NASA Astrophysics Data System (ADS)
Martín-Muñoz, F. J.; Soler-Crespo, L.; Gómez-Briceño, D.
The objective of this paper is to gain some insight into the influence of the surface finishing in the oxidation/corrosion behaviour of 316L and T91 steels in lead bismuth eutectic (LBE). Specimens of both materials with different surface states were prepared (as-received, grinded, grinded and polished, and electrolitically polished) and oxidation tests were carried out at 775 and 825 K from 100 to 2000 h for two different oxygen concentrations and for H 2/H 2O molar ratios of 3 and 0.03. The general conclusion for these tests is that the effect of surface finishing on the corrosion/protection processes is not significant under the tested conditions. In addition the behaviour of weld joints, T91-T91 Tungsten Inert Gas (TIG) and T91-316L have been also studied under similar conditions. The conclusions are that, whereas T91-T91 welded joint shows the same corrosion properties as the parent materials for the conditions tested, AISI 316L-T91 welded joint, present an important dissolution over seam area that it associated to the electrode 309S used for the fabrication process.
Manipulating Mechanics and Chemistry in Precision Optics Finishing
Jacobs, S.D.
Deterministic processing is critical to modern precision optics finishing. Put simply, determinism is the ability to predict an outcome before carrying out an activity. With the availability of computer numerically controlled (CNC) equipment and sophisticated software algorithms, it is now possible to grind and polish optics from a variety of materials to surface shape accuracies of ~20 nm peak-to-valley (p-v), with surface roughness values (measured on white light interferometers over 250 um x 350 um areas) to sub-nm root-mean-square (rms) levels. In the grinding phase the capability now exists to estimate removal rates, surface roughness, and the depth of subsurface damage (SSD) for a previously unprocessed material, knowing its Young's modulus, hardness, and fracture toughness. An understanding of how chemistry aids in the abrasive-driven removal of material from the surface during polishing is also critical, Recent polishing process research reveals the importance of chemistry, specifically slurry pH, for preventing particle agglomeration in order to achieve smooth surface finishes with conventional pad or pitch laps. New sub-aperture polishing processes like magnetorheoogical finishing (MRF) can smooth and shape flat, spherical, aspheric and free-form surfaces within a few process iterations. Difficult to finish optical materials like soft polymer polymethyl methacrylate, microstructured polycrystalline zinc sulfide, and water soluble single-crystal potassium dihydrogen phosphate (KDP) can be finished with MRF. The key is the systematic alteration of MR fluid chemistry and mechanics (i.e. the abrasive) to match the unique physical properties of each workpiece.
[Assessment of precision and accuracy of digital surface photogrammetry with the DSP 400 system].
Krimmel, M; Kluba, S; Dietz, K; Reinert, S
The objective of the present study was to evaluate the precision and accuracy of facial anthropometric measurements obtained through digital 3-D surface photogrammetry with the DSP 400 system in comparison to traditional 2-D photogrammetry. Fifty plaster casts of cleft infants were imaged and 21 standard anthropometric measurements were obtained. For precision assessment the measurements were performed twice in a subsample. Accuracy was determined by comparison of direct measurements and indirect 2-D and 3-D image measurements. Precision of digital surface photogrammetry was almost as good as direct anthropometry and clearly better than 2-D photogrammetry. Measurements derived from 3-D images showed better congruence to direct measurements than from 2-D photos. Digital surface photogrammetry with the DSP 400 system is sufficiently precise and accurate for craniofacial anthropometric examinations. PMID:15832575
Assembly accuracy analysis for small components with a planar surface in large-scale metrology
NASA Astrophysics Data System (ADS)
Wang, Qing; Huang, Peng; Li, Jiangxiong; Ke, Yinglin; Yang, Bingru; Maropoulos, Paul G.
Large-scale mechanical products, such as aircraft and rockets, consist of large numbers of small components, which introduce additional difficulty for assembly accuracy and error estimation. Planar surfaces as key product characteristics are usually utilised for positioning small components in the assembly process. This paper focuses on assembly accuracy analysis of small components with planar surfaces in large-scale volume products. To evaluate the accuracy of the assembly system, an error propagation model for measurement error and fixture error is proposed, based on the assumption that all errors are normally distributed. In this model, the general coordinate vector is adopted to represent the position of the components. The error transmission functions are simplified into a linear model, and the coordinates of the reference points are composed by theoretical value and random error. The installation of a Head-Up Display is taken as an example to analyse the assembly error of small components based on the propagation model. The result shows that the final coordination accuracy is mainly determined by measurement error of the planar surface in small components. To reduce the uncertainty of the plane measurement, an evaluation index of measurement strategy is presented. This index reflects the distribution of the sampling point set and can be calculated by an inertia moment matrix. Finally, a practical application is introduced for validating the evaluation index.
Effect of two different finishing systems on surface roughness of feldspathic and fluorapatite porcelains in ceramo-metal restorations: Comparative in vitro study
Anmol, Cherry; Soni, Sumeet
Objective: The objective of present study was to qualitatively and quantitatively evaluate and compare the effect of two ceramic finishing systems and diamond polishing paste on surface texture of two ceramic materials. Methodology: The 40 test specimens were randomly divided into two main groups (Group I and Group II). Which were subsequently veneered with feldspathic porcelain and fluorapatite leucite porcelain systems respectively. The samples in Test group I and Test group II were subjected to different abrasion and finishing systems (Soft Lex and White silicon and grey rubber respectively). The surface roughness of all the four groups was assessed qualitatively using the scanning Electron Microscope and profilometer. Results: The surface roughness of Feldspathic and fluorapetite porcelain increased after abrasion and finishing as compared to auto-glazed porcelin. The surface roughness was more in grey rubber disc group (Gp Ib) as compared to the soft lex disc groups. After polishing with the diamond paste, there was reduction in the surface roughness of both the disc groups. The Mean Ra values of the Feldspathic porcelain at three intervals were 0.52 ± 0.06, 0.54 ± 0.06, 0.32 ± 0.06 and 0.50 ± 0.04, 1.25 ± 0.10, 0.45 ± 0.6 respectively for grey rubber disc and soft lex groups. The Mean Ra values of Fluorapetite porcelain at three intervals were 0.40 ± 0.06, 0.52 ± 0.06, 0.30 ± 0.03 and 0.41 ± 0.04, 1.17 ± 0.09, 0.39 ± 0.07 respectively for grey rubber disc and soft lex groups. Discussion and Conclusion: The surface roughness was less in the polished samples as compared to the auto-glazed porcelain. The findings were more reinforcing in the soft lex group as compared to the white/grey rubber disc group. Between the two porcelain systems, the Fluorapatite leucite porcelain specimens exhibited better surface smoothness than feldspathic porcelain. PMID:24818090
Accuracy of surface tension measurement from drop shapes: the role of image analysis.
Kalantarian, Ali; Saad, Sameh M I; Neumann, A Wilhelm
Axisymmetric Drop Shape Analysis (ADSA) has been extensively used for surface tension measurement. In essence, ADSA works by matching a theoretical profile of the drop to the extracted experimental profile, taking surface tension as an adjustable parameter. Of the three main building blocks of ADSA, i.e. edge detection, the numerical integration of the Laplace equation for generating theoretical curves and the optimization procedure, only edge detection (that extracts the drop profile line from the drop image) needs extensive study. For the purpose of this article, the numerical integration of the Laplace equation for generating theoretical curves and the optimization procedure will only require a minor effort. It is the aim of this paper to investigate how far the surface tension accuracy of drop shape techniques can be pushed by fine tuning and optimizing edge detection strategies for a given drop image. Two different aspects of edge detection are pursued here: sub-pixel resolution and pixel resolution. The effect of two sub-pixel resolution strategies, i.e. spline and sigmoid, on the accuracy of surface tension measurement is investigated. It is found that the number of pixel points in the fitting procedure of the sub-pixel resolution techniques is crucial, and its value should be determined based on the contrast of the image, i.e. the gray level difference between the drop and the background. On the pixel resolution side, two suitable and reliable edge detectors, i.e. Canny and SUSAN, are explored, and the effect of user-specified parameters of the edge detector on the accuracy of surface tension measurement is scrutinized. Based on the contrast of the image, an optimum value of the user-specified parameter of the edge detector, SUSAN, is suggested. Overall, an accuracy of 0.01mJ/m(2) is achievable for the surface tension determination by careful fine tuning of edge detection algorithms. PMID:24018120
Accuracy of exchange-correlation functionals and effect of solvation on the surface energy of copper
NASA Astrophysics Data System (ADS)
Fishman, Matthew; Zhuang, Houlong L.; Mathew, Kiran; Dirschka, William; Hennig, Richard G.
Surface energies are important for predicting the shapes of nanocrystals and describing the faceting and roughening of surfaces. Copper surfaces are of particular interest in recent years since they are the preferred surfaces for growing graphene using chemical vapor deposition. In this study we calculate the surface energies of copper for the three low-index facets (111), (100), and (110) and one high-index facet, (210), using density-functional theory with both the local-density approximation and various parametrizations of the generalized-gradient approximation to the exchange-correlation functional. To assess the accuracy of the different functionals, we obtain the average surface energies of an isotropic crystal using a broken-bond model. We use this method, which can be generalized to other crystal structures, to compare calculated surface energies to experimental surface energies for fcc crystals. We find that the recent exchange-correlation functionals AM05 and PBEsol are the most accurate functionals for calculating the surface energies of copper. To determine how solvents affect the surface energies of copper, we perform calculations using a continuum solvation model. We find that aqueous solvation changes the overall magnitude of the surface energies only slightly but leads to more isotropic surface energies.
Determining the accuracies of sea-surface temperatures derived from measurements of MODIS and VIIRS
NASA Astrophysics Data System (ADS)
Minnett, P. J.; Kilpatrick, K. A.; Podesta, G. P.; Izaguirre, M.; Williams, E.; Walsh, S.
The appropriate application of sea-surface temperatures (SSTs) derived from MODIS and VIIRS requires knowledge of the errors and uncertainties of the SST fields. The accuracies of the SSTs are determined by comparison with independent measurements, usually derived from drifting and moored buoys, and ship-board radiometers. By using similar cloud detection and clear-sky atmospheric correction algorithms to derived SST from both MODIS's on Terra and Aqua, and the VIIRS on S-NPP a consistent time series of SSTs can be derived from the first useful Terra MODIS data in 2000 to the present, and by using the same approach to assess their accuracies, a consistent set of errors and uncertainties can also be derived. The presentation will provide a summary of recently modified algorithms used to derive SSTs from the MODIS's and VIIRS, and discuss the accuracies of the derived fields, including recent improvements to the VIIRS atmospheric correction algorithm to reduce the effects of instrumental artifacts.
Investigation of crystal surface finish and geometry on single LYSO scintillator detector performance for depth-of-interaction measurement with silicon photomultipliers
NASA Astrophysics Data System (ADS)
Bircher, Chad; Shao, Yiping
Depth of Interaction (DOI) information can improve quality of reconstructed images acquired from Positron Emission Tomography (PET), especially in high resolution and compact scanners dedicated for breast, brain, or small animal imaging applications. Additionally, clinical scanners with time of flight capability can also benefit from DOI information. One of the most promising methods of determining DOI in a crystal involves reading the signal from two ends of a scintillation crystal, and calculating the signal ratio between the two detectors. This method is known to deliver a better DOI resolution with rough crystals compared to highly polished crystals. However, what is still not well studied is how much of a tradeoff is involved between spatial, energy, temporal, and DOI resolutions as a function of the crystal surface treatment and geometry with the use of Silicon Photomultipliers (SiPM) as the photo detectors. This study investigates the effects of different crystal surface finishes and geometries on energy, timing and DOI resolutions at different crystal depths. The results show that for LYSO scintillators of 1.5×1.5×20 mm3 and 2×2×20 mm3 with their surfaces finished from 0.5 to 30 μm roughness, almost the same energy and coincidence timing resolutions were maintained, around 15% and 2.4 ns, respectively across different crystal depths, while the DOI resolutions were steadily improved from worse than 5 mm to better than 2 mm. They demonstrate that crystal roughness, with proper surface preparing, does not have a significant effect on the energy and coincidence timing resolutions in the crystals examined, and there does not appear to be a tradeoff between improving DOI resolution and degrading other detector performances. These results will be valuable to guide the selection of crystal surface conditions for developing a DOI measurable PET detector with a full array of LYSO scintillators coupled to SiPM arrays.
Investigation of Crystal Surface Finish and Geometry on Single LYSO Scintillator Detector Performance for Depth-of-Interaction Measurement with Silicon Photomultipliers
Bircher, Chad
Depth of Interaction (DOI) information can improve quality of reconstructed images acquired from Positron Emission Tomography (PET), especially in high resolution and compact scanners dedicated for breast, brain, or small animal imaging applications. Additionally, clinical scanners with time of flight capability can also benefit from DOI information. One of the most promising methods of determining DOI in a crystal involves reading the signal from two ends of a scintillation crystal, and calculating the signal ratio between the two detectors. This method is known to deliver a better DOI resolution with rough crystals compared to highly polished crystals. However, what is still not well studied is how much of a tradeoff is involved between spatial, energy, temporal, and DOI resolutions as a function of the crystal surface treatment and geometry with the use of Silicon Photomultipliers (SiPM) as the photo detectors. This study investigates the effects of different crystal surface finishes and geometries on energy, timing and DOI resolutions at different crystal depths. The results show that for LYSO scintillators of 1.5×1.5×20 mm3 and 2×2×20 mm3 with their surfaces finished from 0.5 to 30 micron roughness, almost the same energy and coincidence timing resolutions were maintained, around 15% and 2.4 ns respectively across different crystal depths, while the DOI resolutions were steadily improved from worse than 5 mm to better than 2 mm. They demonstrate that crystal roughness, with proper surface preparing, does not have a significant effect on the energy and coincidence timing resolutions in the crystals examined, and there does not appear to be a tradeoff between improving DOI resolution and degrading other detector performances. These results will be valuable to guide the selection of crystal surface conditions for developing a DOI measurable PET detector with a full array of LYSO scintillators coupled to SiPM arrays. PMID:23087497
Finishing of additively manufactured titanium alloy by shape adaptive grinding (SAG)
NASA Astrophysics Data System (ADS)
Beaucamp, Anthony T.; Namba, Yoshiharu; Charlton, Phillip; Jain, Samyak; Graziano, Arthur A.
In recent years, rapid prototyping of titanium alloy components for medical and aeronautics application has become viable thanks to advances in technologies such as electron beam melting (EBM) and selective laser sintering (SLS). However, for many applications the high surface roughness generated by additive manufacturing techniques demands a post-finishing operation to improve the surface quality prior to usage. In this paper, the novel shape adaptive grinding process has been applied to finishing titanium alloy (Ti6Al4V) additively manufactured by EBM and SLS. It is shown that the micro-structured surface layer resulting from the melting process can be removed, and the surface can then be smoothed down to less than 10 nm Ra (starting from 4-5 μm Ra) using only three different diamond grit sizes. This paper also demonstrates application of the technology to freeform shapes, and documents the dimensional accuracy of finished artifacts.
Reconstruction Accuracy Assessment of Surface and Underwater 3D Motion Analysis: A New Approach
de Jesus, Kelly; de Jesus, Karla; Figueiredo, Pedro; Vilas-Boas, João Paulo; Fernandes, Ricardo Jorge; Machado, Leandro José
This study assessed accuracy of surface and underwater 3D reconstruction of a calibration volume with and without homography. A calibration volume (6000 × 2000 × 2500 mm) with 236 markers (64 above and 88 underwater control points—with 8 common points at water surface—and 92 validation points) was positioned on a 25 m swimming pool and recorded with two surface and four underwater cameras. Planar homography estimation for each calibration plane was computed to perform image rectification. Direct linear transformation algorithm for 3D reconstruction was applied, using 1600000 different combinations of 32 and 44 points out of the 64 and 88 control points for surface and underwater markers (resp.). Root Mean Square (RMS) error with homography of control and validations points was lower than without it for surface and underwater cameras (P ≤ 0.03). With homography, RMS errors of control and validation points were similar between surface and underwater cameras (P ≥ 0.47). Without homography, RMS error of control points was greater for underwater than surface cameras (P ≤ 0.04) and the opposite was observed for validation points (P ≤ 0.04). It is recommended that future studies using 3D reconstruction should include homography to improve swimming movement analysis accuracy. PMID:26175796
Accuracy Comparison of Digital Surface Models Created by Unmanned Aerial Systems Imagery and Terrestrial Laser Scanner
NASA Astrophysics Data System (ADS)
Naumann, M.; Geist, M.; Bill, R.; Niemeyer, F.; Grenzdörffer, G.
The main focus of the paper is a comparative study in which we have investigated, whether automatically generated digital surface models (DSM) obtained from unmanned aerial systems (UAS) imagery are comparable with DSM obtained from terrestrial laser scanning (TLS). The research is conducted at a pilot dike for coastal engineering. The effort and the achievable accuracy of both DSMs are compared. The error budgets of these two methods are investigated and the models obtained in each case compared against each other.
Bacteria adhere to food products and processing surfaces that can cross-contaminate other products and work surfaces (Arnold, 1998). Using materials for food processing surfaces that are resistant to bacterial contamination could enhance food safety. Stainless steel, although sus...
Accuracy and precision of stream reach water surface slopes estimated in the field and from maps
Isaak, D.J.; Hubert, W.A.; Krueger, K.L.
The accuracy and precision of five tools used to measure stream water surface slope (WSS) were evaluated. Water surface slopes estimated in the field with a clinometer or from topographic maps used in conjunction with a map wheel or geographic information system (GIS) were significantly higher than WSS estimated in the field with a surveying level (biases of 34, 41, and 53%, respectively). Accuracy of WSS estimates obtained with an Abney level did not differ from surveying level estimates, but conclusions regarding the accuracy of Abney levels and clinometers were weakened by intratool variability. The surveying level estimated WSS most precisely (coefficient of variation [CV] = 0.26%), followed by the GIS (CV = 1.87%), map wheel (CV = 6.18%), Abney level (CV = 13.68%), and clinometer (CV = 21.57%). Estimates of WSS measured in the field with an Abney level and estimated for the same reaches with a GIS used in conjunction with l:24,000-scale topographic maps were significantly correlated (r = 0.86), but there was a tendency for the GIS to overestimate WSS. Detailed accounts of the methods used to measure WSS and recommendations regarding the measurement of WSS are provided.
Convergence and accuracy of kernel-based continuum surface tension models
Williams, M.W.; Kothe, D.B.; Puckett, E.G.
Numerical models for flows of immiscible fluids bounded by topologically complex interfaces possessing surface tension inevitably start with an Eulerian formulation. Here the interface is represented as a color function that abruptly varies from one constant value to another through the interface. This transition region, where the color function varies, is a thin O(h) band along the interface where surface tension forces are applied in continuum surface tension models. Although these models have been widely used since the introduction of the popular CSF method [BKZ92], properties such as absolute accuracy and uniform convergence are often not exhibited in interfacial flow simulations. These properties are necessary if surface tension-driven flows are to be reliably modeled, especially in three dimensions. Accuracy and convergence remain elusive because of difficulties in estimating first and second order spatial derivatives of color functions with abrupt transition regions. These derivatives are needed to approximate interface topology such as the unit normal and mean curvature. Modeling challenges are also presented when formulating the actual surface tension force and its local variation using numerical delta functions. In the following they introduce and incorporate kernels and convolution theory into continuum surface tension models. Here they convolve the discontinuous color function into a mollified function that can support accurate first and second order spatial derivatives. Design requirements for the convolution kernel and a new hybrid mix of convolution and discretization are discussed. The resulting improved estimates for interface topology, numerical delta functions, and surface force distribution are evidenced in an equilibrium static drop simulation where numerically-induced artificial parasitic currents are greatly mitigated.
Ab Initio Calculation of Rate Constants for Molecule-Surface Reactions with Chemical Accuracy.
Piccini, GiovanniMaria; Alessio, Maristella; Sauer, Joachim
The ab initio prediction of reaction rate constants for systems with hundreds of atoms with an accuracy that is comparable to experiment is a challenge for computational quantum chemistry. We present a divide-and-conquer strategy that departs from the potential energy surfaces obtained by standard density functional theory with inclusion of dispersion. The energies of the reactant and transition structures are refined by wavefunction-type calculations for the reaction site. Thermal effects and entropies are calculated from vibrational partition functions, and the anharmonic frequencies are calculated separately for each vibrational mode. This method is applied to a key reaction of an industrially relevant catalytic process, the methylation of small alkenes over zeolites. The calculated reaction rate constants (free energies), pre-exponential factors (entropies), and enthalpy barriers show that our computational strategy yields results that agree with experiment within chemical accuracy limits (less than one order of magnitude). PMID:27008460
3D Surface Reconstruction of Plant Seeds by Volume Carving: Performance and Accuracies
Roussel, Johanna; Geiger, Felix; Fischbach, Andreas; Jahnke, Siegfried; Scharr, Hanno
We describe a method for 3D reconstruction of plant seed surfaces, focusing on small seeds with diameters as small as 200 μm. The method considers robotized systems allowing single seed handling in order to rotate a single seed in front of a camera. Even though such systems feature high position repeatability, at sub-millimeter object scales, camera pose variations have to be compensated. We do this by robustly estimating the tool center point from each acquired image. 3D reconstruction can then be performed by a simple shape-from-silhouette approach. In experiments we investigate runtimes, theoretically achievable accuracy, experimentally achieved accuracy, and show as a proof of principle that the proposed method is well sufficient for 3D seed phenotyping purposes. PMID:27375628
Ab Initio Calculation of Rate Constants for Molecule–Surface Reactions with Chemical Accuracy
Piccini, GiovanniMaria; Alessio, Maristella
Abstract The ab initio prediction of reaction rate constants for systems with hundreds of atoms with an accuracy that is comparable to experiment is a challenge for computational quantum chemistry. We present a divide‐and‐conquer strategy that departs from the potential energy surfaces obtained by standard density functional theory with inclusion of dispersion. The energies of the reactant and transition structures are refined by wavefunction‐type calculations for the reaction site. Thermal effects and entropies are calculated from vibrational partition functions, and the anharmonic frequencies are calculated separately for each vibrational mode. This method is applied to a key reaction of an industrially relevant catalytic process, the methylation of small alkenes over zeolites. The calculated reaction rate constants (free energies), pre‐exponential factors (entropies), and enthalpy barriers show that our computational strategy yields results that agree with experiment within chemical accuracy limits (less than one order of magnitude). PMID:27008460
The 8th Annual AESF/EPA Conference and Exhibit on Pollution Control for the Metal Finishing Industry was held in San Diego, California, February 9, 10, and 11, 1987. The primary objective of the 8th Conference was to continue the dialogue established by the first AESF/EPA Confere...
Evaluation of interproximal finishing techniques for silver amalgam restorations.
Bower, C F; Reinhardt, R A; DuBois, L M
In spite of the incidence of recurrent caries and gingival inflammation surrounding the gingival margins of interproximal silver amalgam restorations, little information exists on the efficacy of finishing procedures in this location. This study was intended to evaluate surface smoothness of interproximal silver amalgams using four finishing techniques. Results indicated that surfaces finished using the carve, floss, and finishing strip polish consistently produced a measurably smoother surface (p less than 0.01) than did the other techniques. The use of finishing strips on the gingival margin of Class II silver amalgam restorations shows promise of improving interproximal surface smoothness. PMID:3462385
Properties of M40J Carbon/PMR-II-50 Composites Fabricated with Desized and Surface Treated Fibers. Characterization of M40J Desized and Finished Fibers
NASA Technical Reports Server (NTRS)
Allred, Ronald E.; Gosau, Jan M.; Shin, E. Eugene; McCorkle, Linda S.; Sutter, James K.; OMalley, Michelle; Gray, Hugh R. (Technical Monitor)
To increase performance and durability of high temperature composites for potential rocket engine components, it is necessary to optimize wetting and interfacial bonding between high modulus carbon fibers and high temperature polyimide resins. It has been previously demonstrated that the electro-oxidative shear treatments used by fiber manufacturers are not effective on higher modulus fibers that have fewer edge and defect sites in the surface crystallites. In addition, sizings commercially supplied on most carbon fibers are not compatible with polyimides. This study was an extension of prior work characterizing the surface chemistry and energy of high modulus carbon fibers (M40J and M60J, Torray) with typical fluorinated polyimide resins, such as PMR-II-50. A continuous desizing system which utilizes environmentally friendly chemical- mechanical processes was developed for tow level fiber and the processes were optimized based on weight loss behavior, surface elemental composition (XPS) and morphology (FE-SEM) analyses, and residual tow strength of the fiber, and the similar approaches have been applied on carbon fabrics. Both desized and further treated with a reactive finish were investigated for the composite reinforcement. The effects of desizing and/or subsequent surface retreatment on carbon fiber on composite properties and performance including fiber-matrix interfacial mechanical properties, thermal properties and blistering onset behavior will be discussed in this presentation.
Simulated studies of wear and friction in total hip prosthesis components with various ball sizes and surface finishes
NASA Technical Reports Server (NTRS)
Swikert, M. A.; Johnson, R. L.
Experiments were conducted on a newly designed total hip joint simulator. The apparatus closely simulates the complex motions and loads of the human hip in normal walking. The wear and friction of presently used appliance configurations and materials were determined. A surface treatment of the metal femoral ball specimens was applied to influence wear. The results of the investigation indicate that wear can be reduced by mechanical treatment of metal femoral ball surfaces. A metallographic examination and surface roughness measurements were made.
Powell, M.
Edge finishing processes have seemed like ideal candidates for automation. Most edge finishing processes are unpleasant, dangerous, tedious, expensive, not repeatable and labor intensive. Estimates place the cost of manual edge finishing processes at 12% of the total cost of fabricating precision parts. For small, high precision parts, the cost of hand finishing may be as high as 305 of the total part cost. Up to 50% of this cost could be saved through automation. This cost estimate includes the direct costs of edge finishing: the machining hours required and the 30% scrap and rework rate after manual finishing. Not included in these estimates are the indirect costs resulting from cumulative trauma disorders and retraining costs caused by the high turnover rate for finishing jobs.. Despite the apparent economic advantages, edge finishing has proven difficult to automate except in low precision and/or high volume production environments. Finishing automation systems have not been deployed successfully in Department of Energy defense programs (DOE/DP) production, A few systems have been attempted but have been subsequently abandoned for traditional edge finishing approaches: scraping, grinding, and filing the edges using modified dental tools and hand held power tools. Edge finishing automation has been an elusive but potentially lucrative production enhancement. The amount of time required for reconfiguring workcells for new parts, the time required to reprogram the workcells to finish new parts, and automation equipment to respond to fixturing errors and part tolerances are the most common reasons cited for eliminating automation as an option for DOE/DP edge finishing applications. Existing automated finishing systems have proven to be economically viable only where setup and reprogramming costs are a negligible fraction of overall production costs.
Effects of Microstructure and Loading on Fracture of Sn-3.8Ag-0.7Cu Joints on Cu Substrates with ENIG Surface Finish
NASA Astrophysics Data System (ADS)
Huang, Z.; Kumar, P.; Dutta, I.; Sidhu, R.; Renavikar, M.; Mahajan, R.
When dropped, electronic packages often undergo failure by propagation of an interfacial crack in solder joints under a combination of tensile and shear loading. Hence, it is crucial to understand and predict the fracture behavior of solder joints under mixed-mode high-rate loading conditions. In this work, the effects of the loading conditions (strain rate and loading angle) and microstructure [interfacial intermetallic compound (IMC) morphology and solder yield strength] on the mixed-mode fracture toughness of Sn-3.8 wt.%Ag-0.7 wt.%Cu solder joints sandwiched between two Cu substrates with electroless nickel immersion gold (ENIG) metallization have been studied, and compared with the fracture behavior of joints attached to bare Cu. Irrespective of the surface finish, the fracture toughness of the solder joints decreased monotonically with strain rate and mode-mixity, both resulting in increased fracture proportion through the interfacial IMC layer. Furthermore, the proportion of crack propagation through the interfacial IMC layer increased with increase in the thickness and the roughness of the interfacial IMC layer and the yield strength of the solder, resulting in a decrease in the fracture toughness of the joint. However, under most conditions, solder joints with ENIG finish showed higher resistance to fracture than joints attached directly to Cu substrates without ENIG metallization. Based on the experimental observations, a fracture mechanism map is constructed correlating the yield strength of the solder, the morphology and thickness of the interfacial IMC, and the fracture mechanisms as well as the fracture toughness values for different solder joints under mode I loading.
Determining the required accuracy of LST products for estimating surface energy fluxes
NASA Astrophysics Data System (ADS)
Pinheiro, A. C.; Reichle, R.; Sujay, K.; Arsenault, K.; Privette, J. L.; Yu, Y.
Land Surface Temperature (LST) is an important parameter to assess the energy state of a surface. Synoptic satellite observations of LST must be used when attempting to estimate fluxes over large spatial scales. Due to the close coupling between LST, root level water availability, and mass and energy fluxes at the surface, LST is particularly useful over agricultural areas to help determine crop water demands and facilitate water management decisions (e.g., irrigation). Further, LST can be assimilated into land surface models to help improve estimates of latent and sensible heat fluxes. However, the accuracy of LST products and its impact on surface flux estimation is not well known. In this study, we quantify the uncertainty limits in LST products for accurately estimating latent heat fluxes over agricultural fields in the Rio Grande River basin of central New Mexico. We use the Community Land Model (CLM) within the Land Information Systems (LIS), and adopt an Ensemble Kalman Filter approach to assimilate the LST fields into the model. We evaluate the LST and assimilation performance against field measurements of evapotranspiration collected at two eddy-covariance towers in semi-arid cropland areas. Our results will help clarify sensor and LST product requirements for future remote sensing systems.
Advance in a nano-accuracy surface profiler with an extended-angle test range
NASA Astrophysics Data System (ADS)
Qian, Shinan; Qian, Kun; Idir, Mourad
An advanced design of a nano-accuracy surface profiler (NSP) is introduced wherein we combined a scanning optical head with non-tilted reference system to facilitate measurements over an extended range of angles. The lateral motion of the beam during testing of a strongly curved mirror induces a systematic error. For a pencil-beam scanning profiler, the arm with varying optical-path lengths should be non-tilted so to eliminate the beam's lateral motion, and the arm for testing larger angles should be short and fixed so to reduce the beam's lateral motion. Our new scheme of having a non-tilted reference system offers an effective, simple, and convenient solution. A beam spot of 0.5-1 mm is used for higher spatial frequency tests in surface-figure measurements. Some preliminary studies and test are demonstrated.
On the accuracy of surface hopping dynamics in condensed phase non-adiabatic problems
NASA Astrophysics Data System (ADS)
Chen, Hsing-Ta; Reichman, David R.
We perform extensive benchmark comparisons of surface hopping dynamics with numerically exact calculations for the spin-boson model over a wide range of energetic and coupling parameters as well as temperature. We find that deviations from golden-rule scaling in the Marcus regime are generally small and depend sensitively on the energetic bias between electronic states. Fewest switches surface hopping (FSSH) is found to be surprisingly accurate over a large swath of parameter space. The inclusion of decoherence corrections via the augmented FSSH algorithm improves the accuracy of dynamical behavior compared to exact simulations, but the effects are generally not dramatic, at least for the case of an environment modeled with the commonly used Debye spectral density.
Effects of pH, surface finish and thermal treatment on the corrosion of AlFeNi aluminum alloy. Characterization of oxide layers
NASA Astrophysics Data System (ADS)
Nabhan, D.; Kapusta, B.; Billaud, P.; Colas, K.; Hamon, D.; Dacheux, N.
The aluminum alloy AlFeNi used as fuel cladding for the Jules Horowitz Reactor (JHR) may undergo corrosion in the reactor environment. In order to qualify the corrosion behavior of the fuel elements of the JHR in accidental conditions, several specimens of AlFeNi have been corroded at 250 °C for different durations (9-34 days) in distilled water at various pH (4.9, 5.2 and 5.6) chosen to simulate that currently considered for the JHR. On all specimens, the only crystalline corrosion product formed is boehmite (AlOOH). The corrosion film is composed of three oxide layers which show through thickness chemical composition variations. The iron-nickel precipitates pre-existing in the metal matrix are present in the inner and intermediate oxide layers though oxidized. For long corrosion times, some of the iron and nickel particles are released in the water and some precipitation is observed at the surface of the oxide layer. The effect of surface finish (as received or polished) and thermal treatment (annealed and not annealed) on the oxide growth rate has also been investigated. For durations over 25 days, pH = 5.6 appears to be more favorable than pH = 5.2 and 4.9 in terms of oxide thickness and weight gain limitation. This effect of pH is however reduced on unpolished specimens. The effect of surface finish on the corrosion behavior as measured by optical microscopy appears to be strong, especially for pH = 4.9 where polished samples exhibited an accelerated evolution of the oxide thickness and of the mass gain. This could be due to the combined effect of a strong acid solution (pH = 4.9) and of the local microstructural changes formed at the interface through polishing. The effect of thermal treatment on the behavior of unpolished AlFeNi specimens during corrosion tests in the conditions investigated was found to be small. In this study, microstructural and chemical analyses were performed on the corroded specimens in order to get a better understanding of the
Accuracy assessment of CKC high-density surface EMG decomposition in biceps femoris muscle
NASA Astrophysics Data System (ADS)
Marateb, H. R.; McGill, K. C.; Holobar, A.; Lateva, Z. C.; Mansourian, M.; Merletti, R.
The aim of this study was to assess the accuracy of the convolution kernel compensation (CKC) method in decomposing high-density surface EMG (HDsEMG) signals from the pennate biceps femoris long-head muscle. Although the CKC method has already been thoroughly assessed in parallel-fibered muscles, there are several factors that could hinder its performance in pennate muscles. Namely, HDsEMG signals from pennate and parallel-fibered muscles differ considerably in terms of the number of detectable motor units (MUs) and the spatial distribution of the motor-unit action potentials (MUAPs). In this study, monopolar surface EMG signals were recorded from five normal subjects during low-force voluntary isometric contractions using a 92-channel electrode grid with 8 mm inter-electrode distances. Intramuscular EMG (iEMG) signals were recorded concurrently using monopolar needles. The HDsEMG and iEMG signals were independently decomposed into MUAP trains, and the iEMG results were verified using a rigorous a posteriori statistical analysis. HDsEMG decomposition identified from 2 to 30 MUAP trains per contraction. 3 ± 2 of these trains were also reliably detected by iEMG decomposition. The measured CKC decomposition accuracy of these common trains over a selected 10 s interval was 91.5 ± 5.8%. The other trains were not assessed. The significant factors that affected CKC decomposition accuracy were the number of HDsEMG channels that were free of technical artifact and the distinguishability of the MUAPs in the HDsEMG signal (P < 0.05). These results show that the CKC method reliably identifies at least a subset of MUAP trains in HDsEMG signals from low force contractions in pennate muscles.
Accuracy evaluation of the optical surface monitoring system on EDGE linear accelerator in a phantom study.
Mancosu, Pietro; Fogliata, Antonella; Stravato, Antonella; Tomatis, Stefano; Cozzi, Luca; Scorsetti, Marta
Frameless stereotactic radiosurgery (SRS) requires dedicated systems to monitor the patient position during the treatment to avoid target underdosage due to involuntary shift. The optical surface monitoring system (OSMS) is here evaluated in a phantom-based study. The new EDGE linear accelerator from Varian (Varian, Palo Alto, CA) integrates, for cranial lesions, the common cone beam computed tomography (CBCT) and kV-MV portal images to the optical surface monitoring system (OSMS), a device able to detect real-time patient׳s face movements in all 6 couch axes (vertical, longitudinal, lateral, rotation along the vertical axis, pitch, and roll). We have evaluated the OSMS imaging capability in checking the phantoms׳ position and monitoring its motion. With this aim, a home-made cranial phantom was developed to evaluate the OSMS accuracy in 4 different experiments: (1) comparison with CBCT in isocenter location, (2) capability to recognize predefined shifts up to 2° or 3cm, (3) evaluation at different couch angles, (4) ability to properly reconstruct the surface when the linac gantry visually block one of the cameras. The OSMS system showed, with a phantom, to be accurate for positioning in respect to the CBCT imaging system with differences of 0.6 ± 0.3mm for linear vector displacement, with a maximum rotational inaccuracy of 0.3°. OSMS presented an accuracy of 0.3mm for displacement up to 1cm and 1°, and 0.5mm for larger displacements. Different couch angles (45° and 90°) induced a mean vector uncertainty < 0.4mm. Coverage of 1 camera produced an uncertainty < 0.5mm. Translations and rotations of a phantom can be accurately detect with the optical surface detector system. PMID:26994827
Effect of Traffic Position Accuracy for Conducting Safe Airport Surface Operations
NASA Technical Reports Server (NTRS)
Jones, Denise R.; Prinzel, Lawrence J., III; Bailey, Randall E.; Arthur, Jarvis J., III; Barnes, James R.
The Next Generation Air Transportation System (NextGen) concept proposes many revolutionary operational concepts and technologies, such as display of traffic information and movements, airport moving maps (AMM), and proactive alerts of runway incursions and surface traffic conflicts, to deliver an overall increase in system capacity and safety. A piloted simulation study was conducted at the National Aeronautics and Space Administration (NASA) Langley Research Center to evaluate the ability to conduct safe and efficient airport surface operations while utilizing an AMM displaying traffic of various position accuracies as well as the effect of traffic position accuracy on airport conflict detection and resolution (CD&R) capability. Nominal scenarios and off-nominal conflict scenarios were conducted using 12 airline crews operating in a simulated Memphis International Airport terminal environment. The data suggest that all traffic should be shown on the airport moving map, whether qualified or unqualified, and conflict detection and resolution technologies provide significant safety benefits. Despite the presence of traffic information on the map, collisions or near collisions still occurred; when indications or alerts were generated in these same scenarios, the incidences were averted.
Fluorophosphonate-functionalised titanium via a pre-adsorbed alkane phosphonic acid: a novel dual action surface finish for bone regenerative applications.
Ayre, Wayne Nishio; Scott, Tom; Hallam, Keith; Blom, Ashley W; Denyer, Stephen; Bone, Heather K; Mansell, Jason P
Enhancing vitamin D-induced human osteoblast (hOB) maturation at bone biomaterial surfaces is likely to improve prosthesis integration with resultant reductions in the need for revision arthroplasty consequent to aseptic loosening. Biomaterials that are less appealing to microorganisms implicated in implant failures through infection are also highly desirable. However, finding surfaces that enhance hOB maturation to active vitamin D yet deter bacteria remain elusive. In addressing this, we have sought to bio-functionalise titanium (Ti) with lysophosphatidic acid (LPA) and related, phosphatase-resistant, LPA analogues. The impetus for this follows our discovery that LPA co-operates with active vitamin D3 metabolites to secure hOB maturation in vitro including cells grown upon Ti. LPA has also been found, by others, to inhibit virulence factor production and biofilm formation of the human opportunistic pathogen Pseudomonas aeruginosa. Collectively, selected LPA species might offer potential dual-action surface finishes for contemporary bone biomaterials. In attaching a phosphatase-resistant LPA analogue to Ti we took advantage of the affinity of alkane phosphonic acids for TiO2. Herein, we provide evidence for the facile development of a dual-action Ti surface for potential orthopaedic and dental applications. Successful conjugation of an LPA analogue (3S)1-fluoro-3-hydroxy-4-(oleoyloxy)butyl-1-phosphonate (FHBP) to the Ti surface was supported through physiochemical characterisation using x-ray photoelectron spectroscopy and secondary ion mass spectrometry. hOB maturation to active vitamin D3 was enhanced for cells grown on FHBP-Ti whilst these same surfaces exhibited clear antiadherent properties towards a clinical isolate of Staphylococcus aureus. PMID:26704553
Accuracy of Implant Position Transfer and Surface Detail Reproduction with Different Impression Materials and Techniques
Alikhasi, Marzieh; Siadat, Hakimeh; Kharazifard, Mohammad Javad
Objectives: The purpose of this study was to compare the accuracy of implant position transfer and surface detail reproduction using two impression techniques and materials. Materials and Methods: A metal model with two implants and three grooves of 0.25, 0.50 and 0.75 mm in depth on the flat superior surface of a die was fabricated. Ten regular-body polyether (PE) and 10 regular-body polyvinyl siloxane (PVS) impressions with square and conical transfer copings using open tray and closed tray techniques were made for each group. Impressions were poured with type IV stone, and linear and angular displacements of the replica heads were evaluated using a coordinate measuring machine (CMM). Also, accurate reproduction of the grooves was evaluated by a video measuring machine (VMM). These measurements were compared with the measurements calculated on the reference model that served as control, and the data were analyzed with two-way ANOVA and t-test at P= 0.05. Results: There was less linear displacement for PVS and less angular displacement for PE in closed-tray technique, and less linear displacement for PE in open tray technique (P<0.001). Also, the open tray technique showed less angular displacement with the use of PVS impression material. Detail reproduction accuracy was the same in all the groups (P>0.05). Conclusion: The open tray technique was more accurate using PE, and also both closed tray and open tray techniques had acceptable results with the use of PVS. The choice of impression material and technique made no significant difference in surface detail reproduction. PMID:27252761
Effect of Coating Surface Finishing on Fatigue Behavior of C450 Steel CAPVD Coated with (Ti,Cr)N
NASA Astrophysics Data System (ADS)
Poursaiedi, E.; Salarvand, A.
The present study evaluated the effect of the surface quality of a custom 450 stainless steel substrate coated with a (Ti,Cr)N nanolayer by cathodic arc physical vapor deposition on fatigue performance in air and in a 3.5% NaCl solution. Scanning electron microscopy was used to locate crack origin sites and characterize the coating. X-ray diffraction was used to analyze the phase formation and measurement of residual stress in the coating. The results showed that the determined in plane residual stress is compressive, with amount of - 2.8 ± 0.4 GPa. Chemical mechanical polishing was used to decrease the coating surface roughness (R a from 0.35 to 0.07 µm). This significantly decreased the area having a high stress concentration and delayed the appearance of micro-cracks in the coating during fatigue testing. The results showed that when the material is tested under axial loading at a maximum alternating stress of 555 to 930 MPa, the fatigue strength of coated specimens with polished surfaces increased 10.6% in air and 26.7% in NaCl solution over the coated specimens with normal surfaces. Post-treatment of the coating increased the fatigue strength 3.5% in air and 10.1% in NaCl solution over the uncoated specimens and the weakness of CAPVD coating was eliminated in the field of fatigue.
Effects of machining accuracy on frequency response properties of thick-screen frequency selective surface
NASA Astrophysics Data System (ADS)
Fang, Chunyi; Gao, Jinsong; Xin, Chen
Electromagnetic theory shows that a thick-screen frequency selective surface (FSS) has many advantages in its frequency response characteristics. In addition, it can be used to make a stealth radome. Therefore, we research in detail how machining accuracy affects the frequency response properties of the FSS in the gigahertz range. Specifically, by using the least squares method applied to machining data, the effects of different machining precision in the samples can be calculated thus obtaining frequency response curves which were verified by testing in the near-field in a microwave dark room. The results show that decreasing roughness and flatness variation leads to an increase in the bandwidth and that an increase in spacing error leads to the center frequency drifting lower. Finally, an increase in aperture error leads to an increase in bandwidth. Therefore, the conclusion is that machining accuracy should be controlled and that a spatial error less than 0.05 mm is required in order to avoid unwanted center frequency drift and a transmittance decrease.
Effects of Regional Topography and Spacecraft Observation Geometry on Surface Soil Moisture Estimation Accuracies
NASA Astrophysics Data System (ADS)
Moghaddam, M.; Akbar, R.; West, R. D.; Colliander, A.; Kim, S.; Dunbar, R. S.
The NASA Soil Moisture Active-Passive Mission (SMAP), launched in January 2015, provides near-daily global surface soil moisture estimates via combined Active Radar and Passive Radiometer observations at various spatial resolutions. The goal of this mission is to enhance our understanding of global carbon and water cycles. This presentation will focus on a comprehensive assessment of the SMAP high resolution radar backscatter data (formally the L1C_S0_HiRes data product) obtained over a 3 km Woody Savanna region in north-central California during a 2.5 month period starting late May 2015. The effects of spacecraft observation geometry (fore- and aft-looks as well as ascending and descending obits) along with regional topography on soil moisture estimation abilities will be examined. Furthermore surface soil moisture retrievals, obtained through utilization of different combinations of observation geometries, will be compared to an existing network of in situsensors. Current electromagnetic scattering and emission models do not properly account for surface topography, therefore physical forward model predictions and observations have unaccounted mismatch errors which also affect soil moisture estimation accuracies. The goal of this study is to quantify these soil moisture prediction errors and highlight the need for new and complete Electromagnetic modeling efforts.
Accuracy Analysis of a Robotic Radionuclide Inspection and Mapping System for Surface Contamination
Mauer, Georg F.; Kawa, Chris
The mapping of localized regions of radionuclide contamination in a building can be a time consuming and costly task. Humans moving hand-held radiation detectors over the target areas are subject to fatigue. A contamination map based on manual surveys can contain significant operator-induced inaccuracies. A Fanuc M16i light industrial robot has been configured for installation on a mobile aerial work platform, such as a tall forklift. When positioned in front of a wall or floor surface, the robot can map the radiation levels over a surface area of up to 3 m by 3 m. The robot's end effector is a commercial alpha-beta radiation sensor, augmented with range and collision avoidance sensors to ensure operational safety as well as to maintain a constant gap between surface and radiation sensors. The accuracy and repeatability of the robotically conducted contamination surveys is directly influenced by the sensors and other hardware employed. This paper presents an in-depth analysis of various non-contact sensors for gap measurement, and the means to compensate for predicted systematic errors that arise during the area survey scans. The range sensor should maintain a constant gap between the radiation counter and the surface being inspected. The inspection robot scans the wall surface horizontally, moving down at predefined vertical intervals after each scan in a meandering pattern. A number of non-contact range sensors can be employed for the measurement of the gap between the robot end effector and the wall. The nominal gap width was specified as 10 mm, with variations during a single scan not to exceed {+-} 2 mm. Unfinished masonry or concrete walls typically exhibit irregularities, such as holes, gaps, or indentations in mortar joints. These irregularities can be sufficiently large to indicate a change of the wall contour. The responses of different sensor types to the wall irregularities vary, depending on their underlying principles of operation. We explored
Imprinting high-gradient topographical structures onto optical surfaces using magnetorheological finishing: manufacturing corrective optical elements for high-power laser applications.
Menapace, Joseph A; Ehrmann, Paul E; Bayramian, Andrew J; Bullington, Amber; Di Nicola, Jean-Michel G; Haefner, Constantin; Jarboe, Jeffrey; Marshall, Christopher; Schaffers, Kathleen I; Smith, Cal
Corrective optical elements form an important part of high-precision optical systems. We have developed a method to manufacture high-gradient corrective optical elements for high-power laser systems using deterministic magnetorheological finishing (MRF) imprinting technology. Several process factors need to be considered for polishing ultraprecise topographical structures onto optical surfaces using MRF. They include proper selection of MRF removal function and wheel sizes, detailed MRF tool and interferometry alignment, and optimized MRF polishing schedules. Dependable interferometry also is a key factor in high-gradient component manufacture. A wavefront attenuating cell, which enables reliable measurement of gradients beyond what is attainable using conventional interferometry, is discussed. The results of MRF imprinting a 23 μm deep structure containing gradients over 1.6 μm / mm onto a fused-silica window are presented as an example of the technique's capabilities. This high-gradient element serves as a thermal correction plate in the high-repetition-rate advanced petawatt laser system currently being built at Lawrence Livermore National Laboratory. PMID:27409216
Imprinting high-gradient topographical structures onto optical surfaces using magnetorheological finishing: Manufacturing corrective optical elements for high-power laser applications
Menapace, Joseph A.; Ehrmann, Paul E.; Bayramian, Andrew J.; Bullington, Amber; Di Nicola, Jean -Michel G.; Haefner, Constantin; Jarboe, Jeffrey; Marshall, Christopher; Schaffers, Kathleen I.; Smith, Cal
Corrective optical elements form an important part of high-precision optical systems. We have developed a method to manufacture high-gradient corrective optical elements for high-power laser systems using deterministic magnetorheological finishing (MRF) imprinting technology. Several process factors need to be considered for polishing ultraprecise topographical structures onto optical surfaces using MRF. They include proper selection of MRF removal function and wheel sizes, detailed MRF tool and interferometry alignment, and optimized MRF polishing schedules. Dependable interferometry also is a key factor in high-gradient component manufacture. A wavefront attenuating cell, which enables reliable measurement of gradients beyond what is attainable using conventional interferometry,more » is discussed. The results of MRF imprinting a 23 μm deep structure containing gradients over 1.6 μm / mm onto a fused-silica window are presented as an example of the technique's capabilities. As a result, this high-gradient element serves as a thermal correction plate in the high-repetition-rate advanced petawatt laser system currently being built at Lawrence Livermore National Laboratory.« less
On the formability, geometrical accuracy, and surface quality of sheet metal parts produced by SPIF
NASA Astrophysics Data System (ADS)
Alves, M. L.; Silva, M. B.; Alves, L. M.; Martins, P. A. F.
Conventional sheet metal forming processes are not suitable for flexible small-batch production and, therefore, are not appropriate for the growing agile manufacturing trends requiring very short life-cycles, development and production lead times. In fact, the present need for flexible sheet metal forming techniques requires the development of innovative technological solutions that are capable of reducing the fixed and capital costs of sheet metal forming to a level where small-batch production becomes economically feasible. Single point incremental forming (SPIF) is a new sheet metal forming process with a high potential economic payoff for rapid prototyping applications and for small quantity production. In general terms a typical SPIF set-up makes use of a small number of low cost active tools components; (i) a blankholder, (ii) a backing plate and (iii) a single point forming tool. The tool path is generated in a CNC machining center and during the process there is no backup die supporting the back surface of the sheet. Despite the contributions of many researchers on the development of industrial applications and better characterization of the forming limits of the process, several key topics related to the mechanics of deformation, likely mode of failure, geometric accuracy and surface quality of the formed parts remain little understood and scarcely systematized. This paper attempts to provide new contributions about the abovementioned issues by means of a comprehensive experimental investigation performed under laboratory controlled conditions.
Impact of pooling on accuracy of hepatitis B virus surface antigen screening of blood donations.
Novack, L; Sarov, B; Goldman-Levi, R; Yahalom, V; Safi, J; Soliman, H; Orgel, M; Yaari, A; Galai, N; Pliskin, J S; Shinar, E
Expenditure on screening blood donations in developing countries can be reduced by testing donations in pools. This study evaluated serological screening in pools for hepatitis B virus (HBV) at the Israeli national blood bank and a hospital blood bank in Gaza, the Palestinian Authority. The accuracy of HBV surface antigen (HBsAg) enzyme immunoassay performed on pools of 3-24 samples was compared with individual tests. Delay in detecting positive samples due to dilution in pools and the possibility of antibody-antigen neutralization were analyzed. The sensitivity of pooled testing for HBsAg was 93-99%, prolonging the window period by 5 days (8.3%). Neutralization of HBsAg by hepatitis B surface antibodies (anti-HBs) could be minimized by testing immediately after pooling. Serological testing for HBsAg in pools may be performed using manually created pools of up to six samples, with 5% loss in sensitivity and a risk of neutralization by anti-HBs present in the donor population. Pooling can therefore be considered as an option only in countries with a low prevalence of HBV. PMID:18486172
Surface accuracy and radiation pattern characteristics of mesh deployable refector antennas
NASA Astrophysics Data System (ADS)
Ueno, Miyoshi; Ebisui, Takashi; Okamato, Teruki; Orikasa, Teruaki; Sugimoto, Toshio; Iso, Akio
To facilitate the growth of mobile satellite communications, both an increase in the Equivalent Isotropically Radiated Power (EIRP) of satellites and improved frequency reuse are required to achiveve compact size, low cost terminal usage, and high channel capacity. High gain and low sidelobe antenna technology are very important for high EIRP and frequency reuse, respectively. These requirements are expected to be met by using a large deployable mesh reflector antenna, which is the key technology for future multibeam moble communications systems. In this paper, surface accruracy and related electrical characteristics are studied using a TETRUS-(Tetra Trigonal Prism Truss) type deployable mesh reflector antenna. Surface accuracy and related electrical characteristics of reflector antennas becaue any distortion of the ideal paraboloidal configuration causes antenna patterns to deteriorate, thereby reducing reflector aperture efficiency and increasing sidelobe and grating lobe levels. The sidelobe and grating lobe characteristics are especially important in frequency reuse. First, we show the problem with the radiation pattern characteristics of TETUS antenna. We then propose a new antenna configuration called the 'HYBRID TETRUS' that improves these characteristics. The mechanical performances of two partial deployable models are also described. Mechanical testing results reveal agreement between the calculated and measured values and high rigidities.
We developed a technique for assessing the accuracy of sub-pixel derived estimates of impervious surface extracted from LANDSAT TM imagery. We utilized spatially coincident
sub-pixel derived impervious surface estimates, high-resolution planimetric GIS data, vector--to-
The scalpel finishing technique: a tooth-friendly way to finish dental composites in anterior teeth.
Kup, Elaine; Tirlet, Gil; Attal, Jean-Pierre
Optimal results can be obtained on direct restorations by the application of layering procedures that combine the accurate morphological insertion of restorative materials with the knowledge of the optical and mechanical properties of both composite resin and natural hard dental tissue. Even if the finishing procedures on restorations, such as margination (the trimming of margins), are minimized by anatomical layering techniques, finishing can still be highly complicated due to a number of pre-finishing sequences using specific instruments proposed in the literature, which include finishing burs and abrasive discs. Finishing procedures performed with a scalpel on polymerized direct composite restorations can improve the quality of the final sculptured surface by developing natural contours and characteristics and by removing the excess restorative material at the tooth-structure margin. Enhanced movement control and fine fingertip perception of the surface texture while moving the scalpel blade allow the operator to detect and cut the excess composite material during the margination procedure and to refine the final anatomy. Avoiding the use of finishing burs during finishing procedures on direct composite restorations may save adjacent enamel surfaces from abrasive damage. The composite surface and margins may also benefit from using the scalpel finishing technique, considering the potential risk of excess removal and surface crazing that the improper use of finishing burs could cause to composite material. The purpose of this article is to propose and describe the scalpel finishing technique step by step, as well as to briefly discuss the advantages of its application within the limits of a clinical case report. PMID:25874271
Statistical downscaling of precipitation using local regression and high accuracy surface modeling method
NASA Astrophysics Data System (ADS)
Zhao, Na; Yue, Tianxiang; Zhou, Xun; Zhao, Mingwei; Liu, Yu; Du, Zhengping; Zhang, Lili
Downscaling precipitation is required in local scale climate impact studies. In this paper, a statistical downscaling scheme was presented with a combination of geographically weighted regression (GWR) model and a recently developed method, high accuracy surface modeling method (HASM). This proposed method was compared with another downscaling method using the Coupled Model Intercomparison Project Phase 5 (CMIP5) database and ground-based data from 732 stations across China for the period 1976-2005. The residual which was produced by GWR was modified by comparing different interpolators including HASM, Kriging, inverse distance weighted method (IDW), and Spline. The spatial downscaling from 1° to 1-km grids for period 1976-2005 and future scenarios was achieved by using the proposed downscaling method. The prediction accuracy was assessed at two separate validation sites throughout China and Jiangxi Province on both annual and seasonal scales, with the root mean square error (RMSE), mean relative error (MRE), and mean absolute error (MAE). The results indicate that the developed model in this study outperforms the method that builds transfer function using the gauge values. There is a large improvement in the results when using a residual correction with meteorological station observations. In comparison with other three classical interpolators, HASM shows better performance in modifying the residual produced by local regression method. The success of the developed technique lies in the effective use of the datasets and the modification process of the residual by using HASM. The results from the future climate scenarios show that precipitation exhibits overall increasing trend from T1 (2011-2040) to T2 (2041-2070) and T2 to T3 (2071-2100) in RCP2.6, RCP4.5, and RCP8.5 emission scenarios. The most significant increase occurs in RCP8.5 from T2 to T3, while the lowest increase is found in RCP2.6 from T2 to T3, increased by 47.11 and 2.12 mm, respectively.
Rovibrational spectra of ammonia. I. Unprecedented accuracy of a potential energy surface used with nonadiabatic corrections.
Huang, Xinchuan; Schwenke, David W; Lee, Timothy J
In this work, we build upon our previous work on the theoretical spectroscopy of ammonia, NH(3). Compared to our 2008 study, we include more physics in our rovibrational calculations and more experimental data in the refinement procedure, and these enable us to produce a potential energy surface (PES) of unprecedented accuracy. We call this the HSL-2 PES. The additional physics we include is a second-order correction for the breakdown of the Born-Oppenheimer approximation, and we find it to be critical for improved results. By including experimental data for higher rotational levels in the refinement procedure, we were able to greatly reduce our systematic errors for the rotational dependence of our predictions. These additions together lead to a significantly improved total angular momentum (J) dependence in our computed rovibrational energies. The root-mean-square error between our predictions using the HSL-2 PES and the reliable energy levels from the HITRAN database for J = 0-6 and J = 7∕8 for (14)NH(3) is only 0.015 cm(-1) and 0.020∕0.023 cm(-1), respectively. The root-mean-square errors for the characteristic inversion splittings are approximately 1∕3 smaller than those for energy levels. The root-mean-square error for the 6002 J = 0-8 transition energies is 0.020 cm(-1). Overall, for J = 0-8, the spectroscopic data computed with HSL-2 is roughly an order of magnitude more accurate relative to our previous best ammonia PES (denoted HSL-1). These impressive numbers are eclipsed only by the root-mean-square error between our predictions for purely rotational transition energies of (15)NH(3) and the highly accurate Cologne database (CDMS): 0.00034 cm(-1) (10 MHz), in other words, 2 orders of magnitude smaller. In addition, we identify a deficiency in the (15)NH(3) energy levels determined from a model of the experimental data. PMID:21280738
Wall Finishes; Carpentry: 901895.
ERIC Educational Resources Information Center
Dade County Public Schools, Miami, FL.
The course outline is designed to provide instruction in selecting, preparing, and installing wall finishing materials. Prerequisites for the course include mastery of building construction plans, foundations and walls, and basic mathematics. Intended for use in grades 11 and 12, the course contains five blocks of study totaling 135 hours of…
The amount of impervious surface in a watershed is a landscape indicator integrating a number of concurrent interactions that influence a watershed's hydrology. Remote sensing data and techniques are viable tools to assess anthropogenic impervious surfaces. However a fundamental ...
Evaluation of the Accuracy of a 3D Surface Imaging System for Patient Setup in Head and Neck Cancer Radiotherapy
Gopan, Olga; Wu Qiuwen
Purpose: To evaluate the accuracy of three-dimensional (3D) surface imaging system (AlignRT) registration algorithms for head-and-neck cancer patient setup during radiotherapy. Methods and Materials: Eleven patients, each undergoing six repeated weekly helical computed tomography (CT) scans during treatment course (total 77 CTs including planning CT), were included in the study. Patient surface images used in AlignRT registration were not captured by the 3D cameras; instead, they were derived from skin contours from these CTs, thereby eliminating issues with immobilization masks. The results from surface registrations in AlignRT based on CT skin contours were compared to those based on bony anatomy registrations in Pinnacle{sup 3}, which was considered the gold standard. Both rigid and nonrigid types of setup errors were analyzed, and the effect of tumor shrinkage was investigated. Results: The maximum registration errors in AlignRT were 0.2 Degree-Sign for rotations and 0.7 mm for translations in all directions. The rigid alignment accuracy in the head region when applied to actual patient data was 1.1 Degree-Sign , 0.8 Degree-Sign , and 2.2 Degree-Sign in rotation and 4.5, 2.7, and 2.4 mm in translation along the vertical, longitudinal, and lateral axes at 90% confidence level. The accuracy was affected by the patient's weight loss during treatment course, which was patient specific. Selectively choosing surface regions improved registration accuracy. The discrepancy for nonrigid registration was much larger at 1.9 Degree-Sign , 2.4 Degree-Sign , and 4.5 Degree-Sign and 10.1, 11.9, and 6.9 mm at 90% confidence level. Conclusions: The 3D surface imaging system is capable of detecting rigid setup errors with good accuracy for head-and-neck cancer. Further investigations are needed to improve the accuracy in detecting nonrigid setup errors.
Recent advances in electronic structure theory and their influence on the accuracy of ab initio potential energy surfaces
NASA Technical Reports Server (NTRS)
Bauschlicher, Charles W., Jr.; Langhoff, Stephen R.; Taylor, Peter R.
Recent advances in electronic structure theory and the availability of high speed vector processors have substantially increased the accuracy of ab initio potential energy surfaces. The recently developed atomic natural orbital approach for basis set contraction has reduced both the basis set incompleteness and superposition errors in molecular calculations. Furthermore, full CI calculations can often be used to calibrate a CASSCF/MRCI approach that quantitatively accounts for the valence correlation energy. These computational advances also provide a vehicle for systematically improving the calculations and for estimating the residual error in the calculations. Calculations on selected diatomic and triatomic systems will be used to illustrate the accuracy that currently can be achieved for molecular systems. In particular, the F+H2 yields HF+H potential energy hypersurface is used to illustrate the impact of these computational advances on the calculation of potential energy surfaces.
Recent advances in electronic structure theory and their influence on the accuracy of ab initio potential energy surfaces
NASA Technical Reports Server (NTRS)
Bauschlicher, Charles W., Jr.; Langhoff, Stephen R.; Taylor, Peter R.
Recent advances in electronic structure theory and the availability of high speed vector processors have substantially increased the accuracy of ab initio potential energy surfaces. The recently developed atomic natural orbital approach for basis set contraction has reduced both the basis set incompleteness and superposition errors in molecular calculations. Furthermore, full CI calculations can often be used to calibrate a CASSCF/MRCI approach that quantitatively accounts for the valence correlation energy. These computational advances also provide a vehicle for systematically improving the calculations and for estimating the residual error in the calculations. Calculations on selected diatomic and triatomic systems will be used to illustrate the accuracy that currently can be achieved for molecular systems. In particular, the F + H2 yields HF + H potential energy hypersurface is used to illustrate the impact of these computational advances on the calculation of potential energy surfaces.
Recent advances in electronic structure theory and their influence on the accuracy of ab initio potential energy surfaces
NASA Astrophysics Data System (ADS)
Bauschlicher, Charles W., Jr.; Langhoff, Stephen R.; Taylor, Peter R.
Recent advances in electronic structure theory and the availability of high speed vector processors have substantially increased the accuracy of ab initio potential energy surfaces. The recently developed atomic natural orbital approach for basis set contraction has reduced both the basis set incompleteness and superposition errors in molecular calculations. Furthermore, full CI calculations can often be used to calibrate a CASSCF/MRCI approach that quantitatively accounts for the valence correlation energy. These computational advances also provide a vehicle for systematically improving the calculations and for estimating the residual error in the calculations. Calculations on selected diatomic and triatomic systems will be used to illustrate the accuracy that currently can be achieved for molecular systems. In particular, the F + H2 yields HF + H potential energy hypersurface is used to illustrate the impact of these computational advances on the calculation of potential energy surfaces.
Recent advances in electronic structure theory and their influence on the accuracy of ab initio potential energy surfaces
NASA Astrophysics Data System (ADS)
Bauschlicher, Charles W., Jr.; Langhoff, Stephen R.; Taylor, Peter R.
Recent advances in electronic structure theory and the availability of high speed vector processors have substantially increased the accuracy of ab initio potential energy surfaces. The recently developed atomic natural orbital approach for basis set contraction has reduced both the basis set incompleteness and superposition errors in molecular calculations. Furthermore, full CI calculations can often be used to calibrate a CASSCF/MRCI approach that quantitatively accounts for the valence correlation energy. These computational advances also provide a vehicle for systematically improving the calculations and for estimating the residual error in the calculations. Calculations on selected diatomic and triatomic systems will be used to illustrate the accuracy that currently can be achieved for molecular systems. In particular, the F+H2 yields HF+H potential energy hypersurface is used to illustrate the impact of these computational advances on the calculation of potential energy surfaces.
Assessment of the accuracy of plasma shape reconstruction by the Cauchy condition surface method in JT-60SA.
Miyata, Y; Suzuki, T; Takechi, M; Urano, H; Ide, S
For the purpose of stable plasma equilibrium control and detailed analysis, it is essential to reconstruct an accurate plasma boundary on the poloidal cross section in tokamak devices. The Cauchy condition surface (CCS) method is a numerical approach for calculating the spatial distribution of the magnetic flux outside a hypothetical surface and reconstructing the plasma boundary from the magnetic measurements located outside the plasma. The accuracy of the plasma shape reconstruction has been assessed by comparing the CCS method and an equilibrium calculation in JT-60SA with a high elongation and triangularity of plasma shape. The CCS, on which both Dirichlet and Neumann conditions are unknown, is defined as a hypothetical surface located inside the real plasma region. The accuracy of the plasma shape reconstruction is sensitive to the CCS free parameters such as the number of unknown parameters and the shape in JT-60SA. It is found that the optimum number of unknown parameters and the size of the CCS that minimizes errors in the reconstructed plasma shape are in proportion to the plasma size. Furthermore, it is shown that the accuracy of the plasma shape reconstruction is greatly improved using the optimum number of unknown parameters and shape of the CCS, and the reachable reconstruction errors in plasma shape and locations of strike points are within the target ranges in JT-60SA. PMID:26233387
Correlation between average tissue depth data and quantitative accuracy of forensic craniofacial reconstructions measured by geometric surface comparison method.
Lee, Won-Joon; Wilkinson, Caroline M; Hwang, Hyeon-Shik; Lee, Sang-Mi
Accuracy is the most important factor supporting the reliability of forensic facial reconstruction (FFR) comparing to the corresponding actual face. A number of methods have been employed to evaluate objective accuracy of FFR. Recently, it has been attempted that the degree of resemblance between computer-generated FFR and actual face is measured by geometric surface comparison method. In this study, three FFRs were produced employing live adult Korean subjects and three-dimensional computerized modeling software. The deviations of the facial surfaces between the FFR and the head scan CT of the corresponding subject were analyzed in reverse modeling software. The results were compared with those from a previous study which applied the same methodology as this study except average facial soft tissue depth dataset. Three FFRs of this study that applied updated dataset demonstrated lesser deviation errors between the facial surfaces of the FFR and corresponding subject than those from the previous study. The results proposed that appropriate average tissue depth data are important to increase quantitative accuracy of FFR. PMID:25739646
Assessment of the accuracy of plasma shape reconstruction by the Cauchy condition surface method in JT-60SA
Miyata, Y.; Suzuki, T.; Takechi, M.; Urano, H.; Ide, S.
For the purpose of stable plasma equilibrium control and detailed analysis, it is essential to reconstruct an accurate plasma boundary on the poloidal cross section in tokamak devices. The Cauchy condition surface (CCS) method is a numerical approach for calculating the spatial distribution of the magnetic flux outside a hypothetical surface and reconstructing the plasma boundary from the magnetic measurements located outside the plasma. The accuracy of the plasma shape reconstruction has been assessed by comparing the CCS method and an equilibrium calculation in JT-60SA with a high elongation and triangularity of plasma shape. The CCS, on which both Dirichlet and Neumann conditions are unknown, is defined as a hypothetical surface located inside the real plasma region. The accuracy of the plasma shape reconstruction is sensitive to the CCS free parameters such as the number of unknown parameters and the shape in JT-60SA. It is found that the optimum number of unknown parameters and the size of the CCS that minimizes errors in the reconstructed plasma shape are in proportion to the plasma size. Furthermore, it is shown that the accuracy of the plasma shape reconstruction is greatly improved using the optimum number of unknown parameters and shape of the CCS, and the reachable reconstruction errors in plasma shape and locations of strike points are within the target ranges in JT-60SA.
Research on the use of particles coming from almond husk as fillers for vinyl plastisols to manufacture hollow pieces with similar surface finishing than wood by using a rotational moulding process
NASA Astrophysics Data System (ADS)
Crespo Amoros, Jose Enrique
PVC pastes or plasticized PVC offer great possibilities in the industrial field in which this research work has been developed since they show great relevance in plastic processing. On one hand, it is important to study these materials from different points of view: quality improvement, wide range of performance, high versatility, low costs,.... On the other hand, most of the industrial fields that usually employ these polymeric materials are characterized by developing products on which aesthetic considerations and surface finishing acquire special relevance. These industrial fields include all those on which new designs require complex shapes and new and novelty surface finishing such as interior design (furniture, wood products,...) toys industry, houseware, shoe industry,.... The main aim of this work is to improve the use of PVC plastisols in these industrial fields by optimizing formulations with new additives (low toxicity plasticizers) and fillers (lignocellulosic wastes) to obtain new materials that minimize damages to environment. In this work, we have developed new plastisol formulations based on the use of low toxicity plasticizers to obtain more ecological plastisols. We have used a biodegradable plasticizer DINCH which is a derivative of a dicarboxilate as substitute of traditional plasticizers based on phthalates. As we are working with relatively new plasticizers (specially at industrial level) we have performed a whole study of its properties by using different experimental analysis techniques such as differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), dynamical-mechanical analysis (DMA) and espectrofotometric techniques (visible and infrared). Furthermore a complete mechanical characterization has been carried out to analyze the most important parameters that influence on materials properties such as processing parameters (temperature and time) and plastisol formulations (mainly plasticizer content). We have also performed a
Satellite and Skin Layer Effects on the Accuracy of Sea Surface Temperature Measurements from the GOES Satellites
NASA Technical Reports Server (NTRS)
Wick, Gary A.; Bates, John J.; Scott, Donna J.
The latest Geostationary Operational Environmental Satellites (GOES) have facilitated significant improvements in our ability to measure sea surface temperature (SST) from geostationary satellites. Nonetheless, difficulties associated with sensor calibration and oceanic near-surface temperature gradients affect the accuracy of the measurements and our ability to estimate and interpret the diurnal cycle of the bulk SST. Overall, measurements of SST from the GOES Imagers on the GOES 8-10 satellites are shown to have very small bias (less than 0.02 K) and rms differences of between 0.6 and 0.9 K relative to buoy observations. Separate consideration of individual measurement times, however, demonstrates systematic bias variations of over 0.6 K with measurement hour. These bias variations significantly affect both the amplitude and shape of estimates of the diurnal SST cycle. Modeled estimates of the temperature difference across the oceanic cool skin and diurnal thermocline show that bias variations up to 0.3 K can result from variability in the near-surface layer. Oceanic near-surface layer and known "satellite midnight" calibration effects, however, explain only a portion of the observed bias variations, suggesting other possible calibration concerns. Methods of explicitly incorporating skin layer and diurnal thermocline effects in satellite bulk SST measurements were explored in an effort to further improve the measurement accuracy. While the approaches contain more complete physics, they do not yet significantly improve the accuracy of bulk SST measurements due to remaining uncertainties in the temperature difference across the near-surface layer.
Anthropogenic impervious surfaces have an important relationship with non-point source pollution (NPS) in urban watersheds. The amount of impervious surface area in a watershed is a key indicator of landscape change. As a single variable, it serves to integrate a number of conc...
Improving the Accuracy of Satellite Sea Surface Temperature Measurements by Explicitly Accounting for the Bulk-Skin Temperature Difference
NASA Technical Reports Server (NTRS)
Wick, Gary A.; Emery, William J.; Castro, Sandra L.; Lindstrom, Eric (Technical Monitor)
The focus of this research was to determine whether the accuracy of satellite measurements of sea surface temperature (SST) could be improved by explicitly accounting for the complex temperature gradients at the surface of the ocean associated with the cool skin and diurnal warm layers. To achieve this goal, work was performed in two different major areas. The first centered on the development and deployment of low-cost infrared radiometers to enable the direct validation of satellite measurements of skin temperature. The second involved a modeling and data analysis effort whereby modeled near-surface temperature profiles were integrated into the retrieval of bulk SST estimates from existing satellite data. Under the first work area, two different seagoing infrared radiometers were designed and fabricated and the first of these was deployed on research ships during two major experiments. Analyses of these data contributed significantly to the Ph.D. thesis of one graduate student and these results are currently being converted into a journal publication. The results of the second portion of work demonstrated that, with presently available models and heat flux estimates, accuracy improvements in SST retrievals associated with better physical treatment of the near-surface layer were partially balanced by uncertainties in the models and extra required input data. While no significant accuracy improvement was observed in this experiment, the results are very encouraging for future applications where improved models and coincident environmental data will be available. These results are included in a manuscript undergoing final review with the Journal of Atmospheric and Oceanic Technology.
Integration of magnetorheological finishing (MRF) technology for ultraprecision optical manufacturing
NASA Astrophysics Data System (ADS)
Pun, Ashley M. H.; Chan, Norman S. W.; Louie, Derek C. H.; Li, Li-Man
Magneto-rheological-finishing (MRF) technology is capable of substantially improving the surface figure of spherical lens to about 1/20 wavelength. Nonetheless, since MRF technology is an ultra-fine polishing process, in which only less than a few microns of material will be removed per cycle, time for making an aspheric surface from a best-fit sphere can be very significant. The situation can be worse if the surface profile is considerably deviated from its best-fit spherical surface. This is not desirable for actual production, and thus a manufacturing cell is proposed to enhance the efficiency of the high precision lens manufacturing process. On the other hand, MRF was suggested to be an alternative for lapping of surface of ceramic lens mould insert. Rather than using the abrasive particles in typical lapping process, the magnetized slurry in MRF is moved past the rotating surface of mould insert locally under the computer-control process so as to achieve the desired surface form accuracy.
High-Accuracy Surface Figure Measurement of Silicon Mirrors at 80 K
NASA Technical Reports Server (NTRS)
Blake, Peter; Mink, Ronald G.; Chambers, John; Davila, Pamela; Robinson, F. David
This report describes the equipment, experimental methods, and first results at a new facility for interferometric measurement of cryogenically-cooled spherical mirrors at the Goddard Space Flight Center Optics Branch. The procedure, using standard phase-shifting interferometry, has an standard combined uncertainty of 3.6 nm rms in its representation of the two-dimensional surface figure error at 80, and an uncertainty of plus or minus 1 nm in the rms statistic itself. The first mirror tested was a concave spherical silicon foam-core mirror, with a clear aperture of 120 mm. The optic surface was measured at room temperature using standard absolute techniques; and then the change in surface figure error from room temperature to 80 K was measured. The mirror was cooled within a cryostat. and its surface figure error measured through a fused-silica window. The facility and techniques will be used to measure the surface figure error at 20K of prototype lightweight silicon carbide and Cesic mirrors developed by Galileo Avionica (Italy) for the European Space Agency (ESA).
Translation of Land Surface Model Accuracy and Uncertainty into Coupled Land-Atmosphere Prediction
NASA Technical Reports Server (NTRS)
Santanello, Joseph A.; Kumar, Sujay; Peters-Lidard, Christa D.; Harrison, Kenneth W.; Zhou, Shuija
Land-atmosphere (L-A) Interactions playa critical role in determining the diurnal evolution of both planetary boundary layer (PBL) and land surface heat and moisture budgets, as well as controlling feedbacks with clouds and precipitation that lead to the persistence of dry and wet regimes. Recent efforts to quantify the strength of L-A coupling in prediction models have produced diagnostics that integrate across both the land and PBL components of the system. In this study, we examine the impact of improved specification of land surface states, anomalies, and fluxes on coupled WRF forecasts during the summers of extreme dry (2006) and wet (2007) land surface conditions in the U.S. Southern Great Plains. The improved land initialization and surface flux parameterizations are obtained through the use of a new optimization and uncertainty estimation module in NASA's Land Information System (US-OPT/UE), whereby parameter sets are calibrated in the Noah land surface model and classified according to a land cover and soil type mapping of the observation sites to the full model domain. The impact of calibrated parameters on the a) spinup of the land surface used as initial conditions, and b) heat and moisture states and fluxes of the coupled WRF Simulations are then assessed in terms of ambient weather and land-atmosphere coupling along with measures of uncertainty propagation into the forecasts. In addition, the sensitivity of this approach to the period of calibration (dry, wet, average) is investigated. Finally, tradeoffs of computational tractability and scientific validity, and the potential for combining this approach with satellite remote sensing data are also discussed.
Cost-effective subaperture approaches to finishing and testing astronomical optics
NASA Astrophysics Data System (ADS)
Tricard, Marc; Shorey, Aric; Hallock, Bob; Murphy, Paul
The fabrication and metrology of astronomical optics are very demanding tasks. In particular, the large sizes needed for astronomical optics and mirrors present significant manufacturing challenges. One of the long-lead aspects (and primary cost drivers) of this process has traditionally been the final polishing and metrology steps. Furthermore, traditional polishing becomes increasingly difficult if the optics are aspheric and/or lightweight. QED Technologies (QED(r)) has developed two novel technologies that have had a significant impact on the production of precision optics. Magnetorheological Finishing (MRF(r)) is a deterministic, production proven, sub-aperture polishing process that can enable significant reductions in cost and lead-time in the production of large optics. MRF routinely achieves surface figure accuracy of better than 30 nm peak-to-valley (better than 5 nm rms) and microroughness better than 1 nm rms on a variety of glasses, glass ceramics and ceramic materials. Unique characteristics of MRF such as a comparatively high, stable removal rate, the conformal nature of the sub-aperture tool and a shear-mode material removal mechanism give it advantages in finishing large and lightweight optics. QED has, for instance, developed the Q22-950F MRF platform which is capable of finishing meter-class optics and the fundamental technology is scalable to even larger apertures. Using MRF for large optics is ideally partnered by a flexible metrology system that provides full aperture metrology of the surface to be finished. A method that provides significant advantages for mirror manufacturing is to characterize the full surface by stitching an array of sub-aperture measurements. Such a technique inherently enables the testing of larger apertures with higher resolution and typically higher accuracy. Furthermore, stitching lends itself to a greater range of optical surfaces that can be measured in a single setup. QED's Subaperture Stitching Interferometer (SSI
Accuracy Assessment of Digital Surface Models Based on WorldView-2 and ADS80 Stereo Remote Sensing Data
Hobi, Martina L.; Ginzler, Christian
Digital surface models (DSMs) are widely used in forest science to model the forest canopy. Stereo pairs of very high resolution satellite and digital aerial images are relatively new and their absolute accuracy for DSM generation is largely unknown. For an assessment of these input data two DSMs based on a WorldView-2 stereo pair and a ADS80 DSM were generated with photogrammetric instruments. Rational polynomial coefficients (RPCs) are defining the orientation of the WorldView-2 satellite images, which can be enhanced with ground control points (GCPs). Thus two WorldView-2 DSMs were distinguished: a WorldView-2 RPCs-only DSM and a WorldView-2 GCP-enhanced RPCs DSM. The accuracy of the three DSMs was estimated with GPS measurements, manual stereo-measurements, and airborne laser scanning data (ALS). With GCP-enhanced RPCs the WorldView-2 image orientation could be optimised to a root mean square error (RMSE) of 0.56 m in planimetry and 0.32 m in height. This improvement in orientation allowed for a vertical median error of −0.24 m for the WorldView-2 GCP-enhanced RPCs DSM in flat terrain. Overall, the DSM based on ADS80 images showed the highest accuracy of the three models with a median error of 0.08 m over bare ground. As the accuracy of a DSM varies with land cover three classes were distinguished: herb and grass, forests, and artificial areas. The study suggested the ADS80 DSM to best model actual surface height in all three land cover classes, with median errors <1.1 m. The WorldView-2 GCP-enhanced RPCs model achieved good accuracy, too, with median errors of −0.43 m for the herb and grass vegetation and −0.26 m for artificial areas. Forested areas emerged as the most difficult land cover type for height modelling; still, with median errors of −1.85 m for the WorldView-2 GCP-enhanced RPCs model and −1.12 m for the ADS80 model, the input data sets evaluated here are quite promising for forest canopy modelling. PMID:22778645
Maintaining the Accuracy of a Sea Surface Height Climate Data Record from Multi-mission Altimeter Data
NASA Astrophysics Data System (ADS)
Ray, R. D.; Beckley, B. D.; Lemoine, F. G.; Zelensky, N. P.; Yang, X.; Mitchum, G. T.; Ricko, M.; Desai, S.; Brown, S. T.
The determination of the rate of change of mean sea level (MSL) has undeniable societal significance. The measurement of geocentric sea level change from satellite altimetry requires an extreme stability of the altimeter measurement system since the signal being measured is at the level of a few mm/yr. Many of the obstacles previously impeding the measurement and validation of estimates of GMSL from satellite altimetry have been overcome (Fu and Haines, 2012). Nonetheless, measuring sea level rates at the precision required for climate science continues to be challenging for at least two reasons: (1) the Terrestrial Reference Frame (TRF) realizations are determined using space geodetic data over finite time spans, and must be periodically updated; (2) the dynamic nature of the Earth engenders global and regional variations in the geopotential which if not properly modeled ultimately cause errors in the computed sea level. Recent developments in Precise Orbit Determinations (POD) due to in particular to revisions to the terrestrial reference frame (i.e. updates to ITRF2008, and the expected availability of ITRF2013) and the development of improved time variable gravity (TVG) models continue to provide improvements to the accuracy and stability of the POD that directly affect mean sea level estimates. Long-term and reliable MSL estimates that rely on data from multiple altimeter missions require the highest possible orbit accuracy and consistency in the use of applied geophysical models in POD computations. The stringent GMSL accuracy requirements are particularly essential for closure of the mass budget over the relative short time period where measurements from Jason-1&2, GRACE, and Argo are coincident. In this presentation we describe the development, utility, and the accuracy maintenance of the MEaSURE's TPJAOS V3.0 sea surface height Climate Data Record (http://podaac.jpl.nasa.gov/dataset/MERGED_TP_J1_OSTM_OST_ALL). We provide an assessment of recent
Use of single-representative reverse-engineered surface-models for RSA does not affect measurement accuracy and precision.
Seehaus, Frank; Schwarze, Michael; Flörkemeier, Thilo; von Lewinski, Gabriela; Kaptein, Bart L; Jakubowitz, Eike; Hurschler, Christof
Implant migration can be accurately quantified by model-based Roentgen stereophotogrammetric analysis (RSA), using an implant surface model to locate the implant relative to the bone. In a clinical situation, a single reverse engineering (RE) model for each implant type and size is used. It is unclear to what extent the accuracy and precision of migration measurement is affected by implant manufacturing variability unaccounted for by a single representative model. Individual RE models were generated for five short-stem hip implants of the same type and size. Two phantom analyses and one clinical analysis were performed: "Accuracy-matched models": one stem was assessed, and the results from the original RE model were compared with randomly selected models. "Accuracy-random model": each of the five stems was assessed and analyzed using one randomly selected RE model. "Precision-clinical setting": implant migration was calculated for eight patients, and all five available RE models were applied to each case. For the two phantom experiments, the 95%CI of the bias ranged from -0.28 mm to 0.30 mm for translation and -2.3° to 2.5° for rotation. In the clinical setting, precision is less than 0.5 mm and 1.2° for translation and rotation, respectively, except for rotations about the proximodistal axis (<4.1°). High accuracy and precision of model-based RSA can be achieved and are not biased by using a single representative RE model. At least for implants similar in shape to the investigated short-stem, individual models are not necessary. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:903-910, 2016. PMID:26553748
Assessing the accuracy and repeatability of automated photogrammetrically generated digital surface models from unmanned aerial system imagery
NASA Astrophysics Data System (ADS)
Chavis, Christopher
Using commercial digital cameras in conjunction with Unmanned Aerial Systems (UAS) to generate 3-D Digital Surface Models (DSMs) and orthomosaics is emerging as a cost-effective alternative to Light Detection and Ranging (LiDAR). Powerful software applications such as Pix4D and APS can automate the generation of DSM and orthomosaic products from a handful of inputs. However, the accuracy of these models is relatively untested. The objectives of this study were to generate multiple DSM and orthomosaic pairs of the same area using Pix4D and APS from flights of imagery collected with a lightweight UAS. The accuracy of each individual DSM was assessed in addition to the consistency of the method to model one location over a period of time. Finally, this study determined if the DSMs automatically generated using lightweight UAS and commercial digital cameras could be used for detecting changes in elevation and at what scale. Accuracy was determined by comparing DSMs to a series of reference points collected with survey grade GPS. Other GPS points were also used as control points to georeference the products within Pix4D and APS. The effectiveness of the products for change detection was assessed through image differencing and observance of artificially induced, known elevation changes. The vertical accuracy with the optimal data and model is ≈ 25 cm and the highest consistency over repeat flights is a standard deviation of ≈ 5 cm. Elevation change detection based on such UAS imagery and DSM models should be viable for detecting infrastructure change in urban or suburban environments with little dense canopy vegetation.
Analysis of spatial variability of near-surface soil moisture to increase rainfall-runoff modelling accuracy in SW Hungary
NASA Astrophysics Data System (ADS)
Hegedüs, P.; Czigány, S.; Pirkhoffer, E.; Balatonyi, L.; Hickey, R.
Between September 5, 2008 and September 5, 2009, near-surface soil moisture time series were collected in the northern part of a 1.7 km2 watershed in SWHungary at 14 monitoring locations using a portable TDR-300 soil moisture sensor. The objectives of this study are to increase the accuracy of soil moisture measurement at watershed scale, to improve flood forecasting accuracy, and to optimize soil moisture sensor density. According to our results, in 10 of 13 cases, a strong correlation exists between the measured soil moisture data of Station 5 and all other monitoring stations; Station 5 is considered representative for the entire watershed. Logically, the selection of the location of the representative measurement point(s) is essential for obtaining representative and accurate soil moisture values for the given watershed. This could be done by (i) employing monitoring stations of higher number at the exploratory phase of the monitoring, (ii) mapping soil physical properties at watershed scale, and (iii) running cross-relational statistical analyses on the obtained data. Our findings indicate that increasing the number of soil moisture data points available for interpolation increases the accuracy of watershed-scale soil moisture estimation. The data set used for interpolation (and estimation of mean antecedent soil moisture values) could be improved (thus, having a higher number of data points) by selecting points of similar properties to the measurement points from the DEM and soil databases. By using a higher number of data points for interpolation, both interpolation accuracy and spatial resolution have increased for the measured soil moisture values for the Pósa Valley.
Accuracy and precision of porosity estimates based on velocity inversion of surface ground-penetrating radar data: A controlled experiment at the Boise Hydrogeophysical Research Site
NASA Astrophysics Data System (ADS)
Bradford, J.; Clement, W.
Although rarely acquired, ground penetrating radar (GPR) data acquired in continuous multi-offset geometries can substantially improve our understanding of the subsurface compared to conventional single offset surveys. This improvement arises because multi-offset data enable full use of the information that the GPR signal can carry. The added information allows us to maximize the material property information extracted from a GPR survey. Of the array of potential multi-offset GPR measurements, traveltime vs offset information enables laterally and vertically continuous electromagnetic (EM) velocity measurements. In turn, the EM velocities provide estimates of water content via petrophysical relationships such as the CRIM or Topp's equations. In fully saturated media the water content is a direct measure of bulk porosity. The Boise Hydrogeophysical Research Site (BHRS) is a experimental wellfield located in a shallow alluvial aquifer near Boise, Idaho. In July, 2006 we conducted a controlled 3D multi-offset GPR experiment at the BHRS designed to test the accuracy of state-of-the-art velocity analysis methodologies. We acquired continuous multi-offset GPR data over an approximately 20 x 30 m 3D area. The GPR system was a Sensors and Software pulseEkko Pro multichannel system with 100 MHz antennas and was configured with 4 receivers and a single transmitter. Data were acquired in off-end geometry for a total of 16 offsets with a 1 m offset interval and 1 m near offset. The data were acquired on a 1 m x 1m grid in four passes, each consisting of a 3 m range of equally spaced offsets. The survey encompassed 13 wells finished to the ~20 m depth of the unconfined aquifer. We established velocity control by acquiring vertical radar profiles (VRPs) in all 13 wells. Preliminary velocity measurements using an established method of reflection tomography were within about 1 percent of local 1D velocity distributions determined from the VRPs. Vertical velocity precision from the
The Diagnostic Value of Surface Markers in Acute Appendicitis; A Diagnostic Accuracy Study
Gholi Mezerji, Naser Mohammad; Rafeie, Mohammad; Shayan, Zahra; Mosayebi, Ghasem
Objective: To determine the diagnostic value of blood cells surface markers in patients with acute appendicitis. Methods: In this cross-sectional study, 71 patients who underwent appendectomy following a diagnosis of appendicitis were recruited during a one-year period. The patients were divided into two groups: patients with histopathologically confirmed acute appendicitis and subjects with normal appendix. Blood cell surface markers of all patients were measured. Univariate and multivariate analytical methods were applied to identify the most useful markers. Receiver operating characteristics (ROC) curves were also used to find the best cut-off point, sensitivity, and specificity. Results: Overall we included 71 patients with mean age of 22.6±10.7 years. Of the 71 cases, 45 (63.4%) had acute appendicitis while 26 (36.6%) were normal. There was no significant difference between two study groups regarding the age (p=0.151) and sex (p=0.142). The initial WBC count was significantly higher in those with acute appendicitis (p=0.033). Maximum and minimum area under the ROC curve in univariate analysis was reported for CD3/RA (0.71) and CD38 (0.533), respectively. Multivariate regression models revealed the percentage of accurate diagnoses based on the combination of γ/δ TCR, CD3/RO, and CD3/RA markers to be 74.65%. Maximum area under the ROC curve (0.79) was also obtained for the same combination. Conclusion: the best blood cell surface markers in the prediction of acute appendicitis were HLA-DR+CD19, a/β TCR, and CD3/RA. The simultaneous use of γ/δ TCR, CD3/RA, and CD3/RO showed the highest diagnostic value in acute appendicitis. PMID:27162905
Improving the Accuracy of Satellite Sea Surface Temperature Measurements by Explicitly Accounting for the Bulk-Skin Temperature Difference
NASA Technical Reports Server (NTRS)
Castro, Sandra L.; Emery, William J.
The focus of this research was to determine whether the accuracy of satellite measurements of sea surface temperature (SST) could be improved by explicitly accounting for the complex temperature gradients at the surface of the ocean associated with the cool skin and diurnal warm layers. To achieve this goal, work centered on the development and deployment of low-cost infrared radiometers to enable the direct validation of satellite measurements of skin temperature. During this one year grant, design and construction of an improved infrared radiometer was completed and testing was initiated. In addition, development of an improved parametric model for the bulk-skin temperature difference was completed using data from the previous version of the radiometer. This model will comprise a key component of an improved procedure for estimating the bulk SST from satellites. The results comprised a significant portion of the Ph.D. thesis completed by one graduate student and they are currently being converted into a journal publication.
Clinical Evaluation of a Laser Surface Scanning System in 120 Patients for Improving Daily Setup Accuracy in Fractionated Radiation Therapy
Moser, Torsten; Habl, Gregor; Uhl, Matthias; Schubert, Kai; Sroka-Perez, Gabriele; Debus, Jürgen; Herfarth, Klaus; Karger, Christian P.
Purpose: To evaluate the clinical suitability of a specific optical surface imaging system to detect setup errors in fractionated radiation therapy. Methods and Materials: The setup correction accuracy of a 3-dimensional laser imaging system was analyzed for 6 different tumor locations with 20 patients each. For each patient, the setup corrections of the megavoltage computed tomography (MVCT) images of a TomoTherapy unit (TomoTherapy, Madison, WI) were compared with those of the laser system for the first 10 fractions. For the laser system, the reference surface either was obtained from the DICOM (Digital Imaging and Communications in Medicine) surface structure delineated on the planning computed tomography images or was acquired with the system itself at the first fraction after the MVCT-based setup correction. Data analysis was performed for both reference types. Results: By use of the DICOM reference image, systematic shifts between 3 and 9 mm were found, depending on the tumor location. For the optical reference, no clinically relevant systematic shifts were found. MVCT-based setup corrections were detected with high accuracy, and only small movements were observed during treatment. Conclusions: Using a reference image acquired with the laser system itself after MVCT-based setup correction appears more reliable than importing the DICOM reference surface. After generation of the optical reference, the laser system may be used to derive setup corrections over a certain number of fractions, but additional radiologic imaging may still be necessary on a regular basis (eg, weekly) or if the corrections of the optical system appear implausibly large. Nevertheless, such a combined application may help to reduce the imaging dose for the patient.
The effect of inhomogeneities on the distance to the last scattering surface and the accuracy of the CMB analysis
Bolejko, Krzysztof
The standard analysis of the CMB data assumes that the distance to the last scattering surface can be calculated using the distance-redshift relation as in the Friedmann model. However, in the inhomogeneous universe, even if (δρ) = 0, the distance relation is not the same as in the unperturbed universe. This can be of serious consequences as a change of distance affects the mapping of CMB temperature fluctuations into the angular power spectrum C{sub l}. In addition, if the change of distance is relatively uniform no new temperature fluctuations are generated. It is therefore a different effect than the lensing or ISW effects which introduce additional CMB anisotropies. This paper shows that the accuracy of the CMB analysis can be impaired by the accuracy of calculation of the distance within the cosmological models. Since this effect has not been fully explored before, to test how the inhomogeneities affect the distance-redshift relation, several methods are examined: the Dyer-Roeder relation, lensing approximation, and non-linear Swiss-Cheese model. In all cases, the distance to the last scattering surface is different than when homogeneity is assumed. The difference can be as low as 1% and as high as 80%. An usual change of the distance is around 20–30%. Since the distance to the last scattering surface is set by the position of the CMB peaks, in order to have a good fit, the distance needs to be adjusted. After correcting the distance, the cosmological parameters change. Therefore, a not properly estimated distance to the last scattering surface can be a major source of systematics. This paper shows that if inhomogeneities are taken into account when calculating the distance then models with positive spatial curvature and with Ω{sub Λ} ∼ 0.8−0.9 are preferred.
Accuracy verification of surface energy components measured by inverse gas chromatography.
Mohammad, Mohammad Amin
Inverse gas chromatography (IGC) measures the retention times of probes which are then used to calculate the surface properties of solids. No method is available to verify how much the measured values are close to their accurate values. According to the chromatographic adhesion law, the accurate determination of the dispersive retention factor (K(a)(CH2)) is a necessary prerequisite to obtain accurate surface components. Employing two equations in this paper, %ΔγS(d), which is the percentage deviation of dispersive component (γS(d)) from its accurate value (γS0(d)), was correlated firstly to %CV(ln K(a)(CH2)), the percentage coefficient of variation of ln K(a)(CH2), and secondly to FEK(a)(CH2), the factor error of K(a)(CH2), via two linear equations. The first equation is to outline the upper and lower limits of the uncertainty range of γS0(d), and the second equation is to estimate γS0(d). To minimize the uncertainty range of γS0(d) to less than ±5%, %CV(ln K(a)(CH2)) should be less than 0.7%. Then considering the sign of FEK(a)(CH2) narrows the uncertainty range to either its upper or lower half. PMID:25976125
The effect of sub-surface volume scattering on the accuracy of ice-sheet altimeter retracking algorithms
NASA Technical Reports Server (NTRS)
Davis, Curt H.
The NASA and ESA retracking algorithms are compared with an algorithm based upon a combined surface and volume (S/V) scattering model. First, the S/V, NASA, and ESA algorithms were used to retrack over 400,000 altimeter return waveforms from the Greenland and Antarctic ice sheets. The surface elevations from the S/V algorithm were compared with the elevations produced by the NASA and ESA algorithms to determine the relative accuracy of these algorithms when subsurface volume-scattering occurs. The results show that the NASA algorithm produced surface elevations within 35 to 50 cm of the S/V algorithm, while the performance of the ESA algorithm was slightly worse. Next, by analyzing several thousand satellite crossover points from the Antarctic data set, we determined the retracking algorithm that produced the most repeatable surface elevations. The elevations derived from the S/V algorithm had the smallest RMS error for the region of the East Antarctic plateau examined here. The ESA algorithm produced erroneous estimates of elevation change when seasonal variations were present; it measured 0.7 to 1.6-m change in elevation over a 6-month period on the East Antarctic plateau where accumulation rates are only 10 cm/year.
Vibratory finishing as a decontamination process
McCoy, M.W.; Arrowsmith, H.W.; Allen, R.P.
The major objective of this research is to develop vibratory finishing into a large-scale decontamination technique that can economicaly remove transuranic and other surface contamination from large volumes of waste produced by the operation and decommissioning of retired nuclear facilities. The successful development and widespread application of this decontamination technique would substantially reduce the volume of waste requiring expensive geologic disposal. Other benefits include exposure reduction for decontamination personnel and reduced risk of environmental contamination. Laboratory-scale studies showed that vibratory finishing can rapidly reduce the contamination level of transuranic-contaminated stainless steel and Plexiglas to well below the 10-nCi/g limit. The capability of vibratory finishing as a decontamination process was demonstrated on a large scale. The first decontamination demonstration was conducted at the Hanford N-Reactor, where a vibratory finisher was installed to reduce personnel exposure during the summer outage. Items decontaminated included fuel spacers, process-tube end caps, process-tube inserts, pump parts, ball-channel inspection tools and miscellaneous hand tools. A second demonstration is currently being conducted in the decontamination facility at the Hanford 231-Z Building. During this demonstration, transuranic-contaminated material from decommissioned plutonium facilities is being decontaminated to <10 nCi/g to minimize the volume of material that will require geologic disposal. Items that are being decontaminated include entire glove boxes, process-hood structural material and panels, process tanks, process-tank shields, pumps, valves and hand tools used during the decommissioning work.
Laplacian drop shapes and effect of random perturbations on accuracy of surface tension measurement for different drop constellations.
Saad, Sameh M I; Neumann, A Wilhelm
Theoretical drop shapes are calculated for three drop constellations: pendant drops, constrained sessile drops, and unconstrained sessile drops. Based on total Gaussian curvature, shape parameter and critical shape parameter are discussed as a function of different drop sizes and surface tensions. The shape parameter is linked to physical parameters for every drop constellation. The as yet unavailable detailed dimensional analysis for the unconstrained sessile drop is presented. Results show that the unconstrained sessile drop shape depends on a dimensionless volume term and the contact angle. Random perturbations are introduced and the accuracy of surface tension measurement is assessed for precise and perturbed profiles of the three drop constellations. It is concluded that pendant drops are the best method for accurate surface tension measurement, followed by constrained sessile drops. The unconstrained sessile drops come last because they tend to be more spherical at low and moderate contact angles. Of course, unconstrained sessile drops are the only option if contact angles are to be measured. PMID:25466689
Dynamic sea surface topography, gravity and improved orbit accuracies from the direct evaluation of SEASAT altimeter data
NASA Technical Reports Server (NTRS)
Marsh, J. G.; Lerch, F.; Koblinsky, C. J.; Klosko, S. M.; Robbins, J. W.; Williamson, R. G.; Patel, G. B.
A method for the simultaneous solution of dynamic ocean topography, gravity and orbits using satellite altimeter data is described. A GEM-T1 based gravitational model called PGS-3337 that incorporates Seasat altimetry, surface gravimetry and satellite tracking data has been determined complete to degree and order 50. The altimeter data is utilized as a dynamic observation of the satellite's height above the sea surface with a degree 10 model of dynamic topography being recovered simultaneously with the orbit parameters, gravity and tidal terms in this model. PGS-3337 has a geoid uncertainty of 60 cm root-mean-square (RMS) globally, with the uncertainty over the altimeter tracked ocean being in the 25 cm range. Doppler determined orbits for Seasat, show large improvements, with the sub-30 cm radial accuracies being achieved. When altimeter data is used in orbit determination, radial orbital accuracies of 20 cm are achieved. The RMS of fit to the altimeter data directly gives 30 cm fits for Seasat when using PGS-3337 and its geoid and dynamic topography model. This performance level is two to three times better than that achieved with earlier Goddard earth models (GEM) using the dynamic topography from long-term oceanographic averages. The recovered dynamic topography reveals the global long wavelength circulation of the oceans with a resolution of 1500 km. The power in the dynamic topography recovery is now found to be closer to that of oceanographic studies than for previous satellite solutions. This is attributed primarily to the improved modeling of the geoid which has occurred. Study of the altimeter residuals reveals regions where tidal models are poor and sea state effects are major limitations.
Assessing the Accuracy of Sentinel-3 SLSTR Sea-Surface Temperature Retrievals Using High Accuracy Infrared Radiiometers on Ships of Opportunity
NASA Astrophysics Data System (ADS)
Minnett, P. J.; Izaguirre, M. A.; Szcszodrak, M.; Williams, E.; Reynolds, R. M.
The assessment of errors and uncertainties in satellite-derived SSTs can be achieved by comparisons with independent measurements of skin SST of high accuracy. Such validation measurements are provided by well-calibrated infrared radiometers mounted on ships. The second generation of Marine-Atmospheric Emitted Radiance Interferometers (M-AERIs) have recently been developed and two are now deployed on cruise ships of Royal Caribbean Cruise Lines that operate in the Caribbean Sea, North Atlantic and Mediterranean Sea. In addition, two Infrared SST Autonomous Radiometers (ISARs) are mounted alternately on a vehicle transporter of NYK Lines that crosses the Pacific Ocean between Japan and the USA. Both M-AERIs and ISARs are self-calibrating radiometers having two internal blackbody cavities to provide at-sea calibration of the measured radiances, and the accuracy of the internal calibration is periodically determined by measurements of a NIST-traceable blackbody cavity in the laboratory. This provides SI-traceability for the at-sea measurements. It is anticipated that these sensors will be deployed during the next several years and will be available for the validation of the SLSTRs on Sentinel-3a and -3b.
Accuracy of surface registration compared to conventional volumetric registration in patient positioning for head-and-neck radiotherapy: A simulation study using patient data
Kim, Youngjun; Li, Ruijiang; Na, Yong Hum; Xing, Lei; Lee, Rena
Purpose: 3D optical surface imaging has been applied to patient positioning in radiation therapy (RT). The optical patient positioning system is advantageous over conventional method using cone-beam computed tomography (CBCT) in that it is radiation free, frameless, and is capable of real-time monitoring. While the conventional radiographic method uses volumetric registration, the optical system uses surface matching for patient alignment. The relative accuracy of these two methods has not yet been sufficiently investigated. This study aims to investigate the theoretical accuracy of the surface registration based on a simulation study using patient data. Methods: This study compares the relative accuracy of surface and volumetric registration in head-and-neck RT. The authors examined 26 patient data sets, each consisting of planning CT data acquired before treatment and patient setup CBCT data acquired at the time of treatment. As input data of surface registration, patient's skin surfaces were created by contouring patient skin from planning CT and treatment CBCT. Surface registration was performed using the iterative closest points algorithm by point–plane closest, which minimizes the normal distance between source points and target surfaces. Six degrees of freedom (three translations and three rotations) were used in both surface and volumetric registrations and the results were compared. The accuracy of each method was estimated by digital phantom tests. Results: Based on the results of 26 patients, the authors found that the average and maximum root-mean-square translation deviation between the surface and volumetric registrations were 2.7 and 5.2 mm, respectively. The residual error of the surface registration was calculated to have an average of 0.9 mm and a maximum of 1.7 mm. Conclusions: Surface registration may lead to results different from those of the conventional volumetric registration. Only limited accuracy can be achieved for patient
Effect of vertebral surface extraction on registration accuracy: a comparison of registration results for iso-intensity algorithms applied to computed tomography images
NASA Astrophysics Data System (ADS)
Herring, Jeannette L.; Maurer, Calvin R., Jr.; Muratore, Diane M.; Galloway, Robert L., Jr.; Dawant, Benoit M.
This paper presents a comparison of iso-intensity-based surface extraction algorithms applied to computed tomography (CT) images of the spine. The extracted vertebral surfaces are used in surface-based registration of CT images to physical space, where our ultimate goal is the development of a technique that can be used for image-guided spinal surgery. The surface extraction process has a direct effect on image-guided surgery in two ways: the extracted surface must provide an accurate representation of the actual surface so that a good registration can be achieved, and the number of polygons in the mesh representation of the extracted surface must be small enough to allow the registration to be performed quickly. To examine the effect of the surface extraction process on registration error and run time, we have performed a large number of experiments on two plastic spine phantoms. Using a marker-based system to assess accuracy, we have found that submillimetric registration accuracy can be achieved using a point-to- surface registration algorithm with simplified and unsimplified members of the general class of iso-intensity- based surface extraction algorithms. This research has practical implications, since it shows that several versions of the widely available class of intensity-based surface extraction algorithms can be used to provide sufficient accuracy for vertebral registration. Since intensity-based algorithms are completely deterministic and fully automatic, this finding simplifies the pre-processing required for image-guided back surgery.
The Magnetorheological Finishing (MRF) of Potassium Dihydrogen Phosphate (KDP) Crystal with Fe3O4 Nanoparticles
NASA Astrophysics Data System (ADS)
Ji, Fang; Xu, Min; Wang, Chao; Li, Xiaoyuan; Gao, Wei; Zhang, Yunfei; Wang, Baorui; Tang, Guangping; Yue, Xiaobin
The cubic Fe3O4 nanoparticles with sharp horns that display the size distribution between 100 and 200 nm are utilized to substitute the magnetic sensitive medium (carbonyl iron powders, CIPs) and abrasives (CeO2/diamond) simultaneously which are widely employed in conventional magnetorheological finishing fluid. The removal rate of this novel fluid is extremely low compared with the value of conventional one even though the spot of the former is much bigger. This surprising phenomenon is generated due to the small size and low saturation magnetization ( M s) of Fe3O4 and corresponding weak shear stress under external magnetic field according to material removal rate model of magnetorheological finishing (MRF). Different from conventional D-shaped finishing spot, the low M s also results in a shuttle-like spot because the magnetic controllability is weak and particles in the fringe of spot are loose. The surface texture as well as figure accuracy and PSD1 (power spectrum density) of potassium dihydrogen phosphate (KDP) is greatly improved after MRF, which clearly prove the feasibility of substituting CIP and abrasive with Fe3O4 in our novel MRF design.
The Magnetorheological Finishing (MRF) of Potassium Dihydrogen Phosphate (KDP) Crystal with Fe3O4 Nanoparticles.
Ji, Fang; Xu, Min; Wang, Chao; Li, Xiaoyuan; Gao, Wei; Zhang, Yunfei; Wang, Baorui; Tang, Guangping; Yue, Xiaobin
The cubic Fe3O4 nanoparticles with sharp horns that display the size distribution between 100 and 200 nm are utilized to substitute the magnetic sensitive medium (carbonyl iron powders, CIPs) and abrasives (CeO2/diamond) simultaneously which are widely employed in conventional magnetorheological finishing fluid. The removal rate of this novel fluid is extremely low compared with the value of conventional one even though the spot of the former is much bigger. This surprising phenomenon is generated due to the small size and low saturation magnetization (M s) of Fe3O4 and corresponding weak shear stress under external magnetic field according to material removal rate model of magnetorheological finishing (MRF). Different from conventional D-shaped finishing spot, the low M s also results in a shuttle-like spot because the magnetic controllability is weak and particles in the fringe of spot are loose. The surface texture as well as figure accuracy and PSD1 (power spectrum density) of potassium dihydrogen phosphate (KDP) is greatly improved after MRF, which clearly prove the feasibility of substituting CIP and abrasive with Fe3O4 in our novel MRF design. PMID:26858161
NICE3 Textile Finishing Process
Blazek, S.
This new energy-saving approach to fabric finishing can help our domestic textile industry compete in an increasingly competitive global market. Learn how this new technology can lower your maintenance costs and increase your productivity.
Buffered Electropolishing – A New Way for Achieving Extremely Smooth Surface Finish on Nb SRF Cavities to be Used in Particle Accelerators
Hui Tian, Charles Reece, Michael Kelley
Future accelerators require unprecedented cavity performance, which is strongly influenced by interior surface nano-smoothness. Electropolishing (EP) is the technique of choice to be developed for high-field superconducting radio frequency (SRF) cavities. Electrochemical impedance spectroscopy (EIS) and related techniques point to the electropolishing mechanism of Nb in a sulphuric and hydrofluoric acid electrolyte controlled by a compact surface salt film under F- diffusion-limited mass transport control. These and other findings are guiding a systematic characterization to form the basis for cavities process optimization.
Improving accuracy in coronary lumen segmentation via explicit calcium exclusion, learning-based ray detection and surface optimization
NASA Astrophysics Data System (ADS)
Lugauer, Felix; Zhang, Jingdan; Zheng, Yefeng; Hornegger, Joachim; Kelm, B. Michael
Invasive cardiac angiography (catheterization) is still the standard in clinical practice for diagnosing coronary artery disease (CAD) but it involves a high amount of risk and cost. New generations of CT scanners can acquire high-quality images of coronary arteries which allow for an accurate identification and delineation of stenoses. Recently, computational fluid dynamics (CFD) simulation has been applied to coronary blood flow using geometric lumen models extracted from CT angiography (CTA). The computed pressure drop at stenoses proved to be indicative for ischemia-causing lesions, leading to non-invasive fractional flow reserve (FFR) derived from CTA. Since the diagnostic value of non-invasive procedures for diagnosing CAD relies on an accurate extraction of the lumen, a precise segmentation of the coronary arteries is crucial. As manual segmentation is tedious, time-consuming and subjective, automatic procedures are desirable. We present a novel fully-automatic method to accurately segment the lumen of coronary arteries in the presence of calcified and non-calcified plaque. Our segmentation framework is based on three main steps: boundary detection, calcium exclusion and surface optimization. A learning-based boundary detector enables a robust lumen contour detection via dense ray-casting. The exclusion of calcified plaque is assured through a novel calcium exclusion technique which allows us to accurately capture stenoses of diseased arteries. The boundary detection results are incorporated into a closed set formulation whose minimization yields an optimized lumen surface. On standardized tests with clinical data, a segmentation accuracy is achieved which is comparable to clinical experts and superior to current automatic methods.
The effect of three finishing systems on four esthetic restorative materials.
Hoelscher, D C; Neme, A M; Pink, F E; Hughes, P J
Previous studies have investigated the finishing and smoothness of composite and traditional glass-ionomer restorations, but few have included resin-modified glass-ionomer cements or more recent finishing systems. The results of using three different finishing systems (Sof-Lex, Enhance, finishing burs) on two composites (Silux, Prisma TPH), a traditional glass ionomer (Ketac-Fil), and a resin-modified glass ionomer (Fuji II LC) were studied. Sixty samples were condensed into sectioned acrylic tubes, covered with a Mylar matrix plus a glass slide at each surface, then cured as per the manufacturers' instructions. Samples were randomized to three groups of five for each material and testing with a Surfanalyzer 4000 of unfinished samples (cured with Mylar matrix) was done to obtain baseline average surface roughness (Ra). Samples were then finished as per the manufacturers' instructions using polishing disks, abrasive impregnated disks, and finishing burs before further surface testing. Samples finished with burs and with abrasive impregnated disks were further polished using polishing paste (Prisma Gloss) and again tested. Data were analyzed with ANOVA testing and Tukey's HSD pairwise comparison. Initial testing after randomization to groups showed no significant difference in surface roughness (P = 0.24). Two-factor analysis revealed no significant difference between materials (P = 0.34), a significant difference in method of finish (P < or = 0.00), with no significant interaction between type of material and method of finish (P = 0.11). Aluminum oxide disk and impregnated disk systems provided the best finish for microfilled composite and both glass-ionomer materials (P < or = 0.00). No significant difference in method of finish existed with the hybrid composite (P = 0.07). Overall, esthetic restorative material finishing is best accomplished using abrasive impregnated disks or aluminum oxide disks. Finishing burs gave a significantly rougher surface than the
An assessment of the near-surface accuracy of the international geomagnetic reference field 1980 model of the main geomagnetic field
Peddie, N.W.; Zunde, A.K.
The new International Geomagnetic Reference Field (IGRF) model of the main geomagnetic field for 1980 is based heavily on measurements from the MAGSAT satellite survey. Assessment of the accuracy of the new model, as a description of the main field near the Earth's surface, is important because the accuracy of models derived from satellite data can be adversely affected by the magnetic field of electric currents in the ionosphere and the auroral zones. Until now, statements about its accuracy have been based on the 6 published assessments of the 2 proposed models from which it was derived. However, those assessments were either regional in scope or were based mainly on preliminary or extrapolated data. Here we assess the near-surface accuracy of the new model by comparing it with values for 1980 derived from annual means from 69 magnetic observatories, and by comparing it with WC80, a model derived from near-surface data. The comparison with observatory-derived data shows that the new model describes the field at the 69 observatories about as accurately as would a model derived solely from near-surface data. The comparison with WC80 shows that the 2 models agree closely in their description of D and I near the surface. These comparisons support the proposition that the new IGRF 1980 main-field model is a generally accurate description of the main field near the Earth's surface in 1980. ?? 1985.
Environmentally friendly antibacterial cotton textiles finished with siloxane sulfopropylbetaine.
Chen, Shiguo; Chen, Shaojun; Jiang, Song; Xiong, Meiling; Luo, Junxuan; Tang, Jiaoning; Ge, Zaochuan
This paper reports a novel environmentally friendly antibacterial cotton textile finished with reactive siloxane sulfopropylbetaine(SSPB). The results show that SSPB can be covalently bound onto the cotton textile surface, imparting perdurable antibacterial activity. The textiles finished with SSPB have been investigated systematically from the mechanical properties, thermal stability, hydrophilic properties and antibacterial properties. It is found that the hydrophilicity and breaking strength are improved greatly after the cotton textiles are finished with SSPB. Additionally, the cotton textiles finished with SSPB exhibit good antibacterial activities against gram-positive bacteria Staphylococcus aureus (S.aureus, ATCC 6538), gram-negative bacteria Escherichia coli (E.coli, 8099) and fungi Candida albicans (C.albicans, ATCC 10231). Moreover, SSPB is nonleachable from the textiles, and it does not induce skin stimulation and is nontoxic to animals. Thus, SSPB is ideal candidate for environmentally friendly antibacterial textile applications. PMID:21417413
Effect of Pd Thickness on the Interfacial Reaction and Shear Strength in Solder Joints Between Sn-3.0Ag-0.5Cu Solder and Electroless Nickel/Electroless Palladium/Immersion Gold (ENEPIG) Surface Finish
NASA Astrophysics Data System (ADS)
Kim, Young Min; Park, Jin-Young; Kim, Young-Ho
Intermetallic compound formation at the interface between Sn-3.0Ag-0.5Cu (SAC) solders and electroless nickel/electroless palladium/immersion gold (ENEPIG) surface finish and the mechanical strength of the solder joints were investigated at various Pd thicknesses (0 μm to 0.5 μm). The solder joints were fabricated on the ENEPIG surface finish with SAC solder via reflow soldering under various conditions. The (Cu,Ni)6Sn5 phase formed at the SAC/ENEPIG interface after reflow in all samples. When samples were reflowed at 260°C for 5 s, only (Cu,Ni)6Sn5 was observed at the solder interfaces in samples with Pd thicknesses of 0.05 μm or less. However, the (Pd,Ni)Sn4 phase formed on (Cu,Ni)6Sn5 when the Pd thickness increased to 0.1 μm or greater. A thick and continuous (Pd,Ni)Sn4 layer formed over the (Cu,Ni)6Sn5 layer, especially when the Pd thickness was 0.3 μm or greater. High-speed ball shear test results showed that the interfacial strengths of the SAC/ENEPIG solder joints decreased under high strain rate due to weak interfacial fracture between (Pd,Ni)Sn4 and (Cu,Ni)6Sn5 interfaces when the Pd thickness was greater than 0.3 μm. In the samples reflowed at 260°C for 20 s, only (Cu,Ni)6Sn5 formed at the solder interfaces and the (Pd,Ni)Sn4 phase was not observed in the solder interfaces, regardless of Pd thickness. The shear strength of the SAC/ENIG solder joints was the lowest of the joints, and the mechanical strength of the SAC/ENEPIG solder joints was enhanced as the Pd thickness increased to 0.1 μm and maintained a nearly constant value when the Pd thickness was greater than 0.1 μm. No adverse effect on the shear strength values was observed due to the interfacial fracture between (Pd,Ni)Sn4 and (Cu,Ni)6Sn5 since the (Pd,Ni)Sn4 phase was already separated from the (Cu,Ni)6Sn5 interface. These results indicate that the interfacial microstructures and mechanical strength of solder joints strongly depend on the Pd thickness and reflow conditions.
The Accuracy of Conformation of a Generic Surface Mesh for the Analysis of Facial Soft Tissue Changes
Cheung, Man Yan; Almukhtar, Anas; Keeling, Andrew; Hsung, Tai-Chiu; Ju, Xiangyang; McDonald, James; Ayoub, Ashraf; Khambay, Balvinder Singh
Purpose Three dimensional analysis of the face is required for the assessment of complex changes following surgery, pathological conditions and to monitor facial growth. The most suitable method may be "dense surface correspondence". Materials and Methods This method utilizes a generic facial mesh and "conformation process" to establish anatomical correspondences between two facial images. The aim of this study was to validate the use of conformed meshes to measure simulated maxillary and mandibular surgical movements. The "simulation" was performed by deforming the actual soft tissues of the participant during image acquisition. The study was conducted on 20 volunteers and used 77 facial landmarks pre-marked over six anatomical regions; left cheek, right cheek, left upper lip, philtrum, right upper lip and chin region. Each volunteer was imaged at rest and after performing 5 different simulated surgical procedures using 3D stereophotogrammetry. The simulated surgical movement was determined by measuring the Euclidean distances and the mean absolute x, y and z distances of the landmarks making up the six regions following digitization. A generic mesh was then conformed to each of the aligned six facial 3D images. The same six regions were selected on the aligned conformed simulated meshes and the surgical movement determined by determining the Euclidean distances and the mean absolute x, y and z distances of the mesh points making up the six regions were determined. Results In all cases the mean Euclidian distance between the simulated movement and conformed region was less than 0.7mm. For the x, y and z directions the majority of differences in the mean absolute distances were less than 1.0mm except in the x-direction for the left and right cheek regions, which was above 2.0mm. Conclusions This concludes that the conformation process has an acceptable level of accuracy and is a valid method of measuring facial change between two images i.e. pre- and
Comparative Evaluation of the Efficiency of Four Ceramic Finishing Systems
Aravind, Prasad; Razak, P Abdul; Francis, P G; Issac, Johnson K; Shanoj, R P; Sasikumar, T P
Aim: To compare the effect of four different finishing systems and diamond paste on ceramic roughness with the objectives of evaluating the roughness of ceramic surface of prepared specimens after abrasion, finishing and polishing. Materials & Methods: A total of 50 test specimens were fabricated in the form of discs of diameter 13mm and 0.6mm thickness. Test specimens were then randomly distributed into five groups of 10 and coded. All the test specimens were then abraded with 125μm diamond in unidirectional motion to create surface roughness that will simulate occlusal or incisal correction. The values were recorded and the specimens were then finished using the various finishing systems. multiple range tests by Duncan's procedure. One way Anova was used to calculate the p-value Results:After fini shing, the Ra,Rq,Rz and Rt values showed a tendency to decline to levels much inferior to the values obtained after the preparation of the specimens. Ra values of group III specimens were slightly higher and the increase was significant. The highest Rt value [5.29] obtained after polishing is below the lowest roughness values [7.42] obtained after finishing the specimens. Conclusions: Finishing and polishing procedures have a significant role in reducing the roughness of ceramics.Following abrasion with diamond point to simulate clinical adjustment the roughness values doubled when compared to the initial reading.Ra, Rq,Rz and Rt values suggest that Sof lex is the most efficient of all the systems tested followed by auto glazing.After the final diamond paste polishing, sof lex group specimens showed the best finish and auto glazed specimens showed a value almost as equal to the so flex group. How to cite this article: Aravind P, Razak PA, Francis PG, Issac JK, Shanoj RP, Sasikumar TP. Comparative Evaluation of the Efficiency of Four Ceramics Finishing Systems. J Int Oral Health 2013; 5(5):59-64. PMID:24324306
Efficient dielectric fluid approach in electrodischarge finish machining on the material surface roughness of titanium alloy Ti-621/0.8
NASA Astrophysics Data System (ADS)
Mihai, N. V.; Brabie, G.
This study was developed to reveal the correlation between current intensity and pulse off time with surface roughness of Ti-621/0.8 in fine EDM machining, in a unique manner of dielectric fluid approach. Depth of cut was taken in consideration to be not as high 1 gm due to the fact that good results were taken for more less heights before. In the case of Ti alloy (Ti-621/0.8) bar, EDM machining with low parameters (limited 110 V) is a delicate process, in which reaching SR under 1 gm is a challenge. Cooper and Graphite electrodes were used, die sinker oil dielectric from machine manufacture was used, without thermal modification to workpiece or electrode, just active dielectric compensatory fluid pumping solution with 0.5 MPa.
Diagnostic yield and accuracy of postmortem cytological sampling from the brain surface of animals with neurological abnormalities.
Wünsche, S; Rosati, M; Matiasek, K
Clarification of central nervous system (CNS) disorders frequently requires pathological investigation via brain biopsy or postmortem examination. The use of cytology is usually restricted to diagnosis of mass lesions and septic meningitis. The value of brain cytology at postmortem examination has not been explored sufficiently. This study aimed to clarify the diagnostic value of meningeal imprint cytology at postmortem brain examination. Samples were taken from cerebrum and cerebellum and stained with the modified Wright stain and with haematoxylin-eosin. The slides were evaluated and findings were compared to brain histopathology with respect to resemblance, discrepancy and diagnostic validity. The study included 169 cases involving multiple animal species. Histopathology identified inflammatory disorders in 60/135 (44.4%) cases, neoplasia in 19/135 (14.1%) and non-infiltrative diseases in 56/135 (41.5%). Cytology revealed pathological changes in 79/135 (58.5%) of these cases. The histopathological diagnosis was reproduced in 57/135 (42.2%) cases, 43/57 (75.4%) of which were inflammatory. Non-diagnostic cases included 16/135 (11.9%) with sub-diagnostic cytological features and 3/135 (2.2%) with unclear phenomena. In 55/135 (40.7%) of brains with histological lesions, cytology proved inferior, providing negative results, including 40/55 (72.7%) cases with non-infiltrative diseases, 12/55 (21.8%) with inflammation and 3/55 (5.5%) with neoplasia. Conversely, 3/34 (8.8%) of controls showed cytological abnormalities. Cytological sampling from CNS adds to the sensitivity of neuropathological investigations, even if restricted to non-invasive surface imprints. The diagnostic accuracy exceeds 40%, with infiltrative diseases being five times more likely to be detected than non-infiltrative diseases. PMID:27009475
Magnetorheological finishing and subaperture stitching interferometry of large and lightweight optics
NASA Astrophysics Data System (ADS)
Shorey, Aric B.; Kordonski, William; Tricard, Marc
Significant challenges are faced in the manufacturing of the complex optics for the next generation of astronomical telescopes. Process improvements are required to establish cost effective techniques to finish the optics to the tight specification required in a timely manner. An added complication is realized when the optics are lightweight. The non-uniform support of the face-sheet in this case requires special efforts to avoid a print-through of the cell structure due to fabrication processes, gravity and/or cryogenic effects. Magnetorheological finishing (MRF) is a deterministic, sub-aperture polishing process that has been a revolutionary success in the fabrication of optics in the size range of 10-1000 mm. This production proven process is capable of polishing flats, spheres, aspheres and cylinders to a surface figure accuracy of better than 30 nm peak-to-valley (better than 5 nm rms), and microroughness better than 1 nm rms on a variety of glasses, glass ceramics and single crystal materials. Unique characteristics of MRF such as a high, stable removal rate, conformal nature of the sub-aperture tool and shear mode of material removal give it advantages in the finishing of large and lightweight optics. These qualities provide for a cost-effective process with a high rate of convergence that requires few iterations. Such a technology is ideally complemented by a system for the stitching of interferometric sub-aperture data. Stitching inherently enables the testing of larger apertures with higher resolution and, thanks to the built-in calibration, even to higher accuracy in many situations. While this approach enables the non-null testing of parts with greater aspheric departure and can lead to a significantly reduced non-common air path in the testing of long-radius concave parts, it is especially effective for convex optics. That is, stitching is particularly well suited to the testing of secondary mirrors and, alongside the testing of the off-axis primary
Potential of EnMAP spaceborne imaging spectroscopy for the prediction of common surface soil properties and expected accuracy
NASA Astrophysics Data System (ADS)
Chabrillat, Sabine; Foerster, Saskia; Steinberg, Andreas; Stevens, Antoine; Segl, Karl
There is a renewed awareness of the finite nature of the world's soil resources, growing concern about soil security, and significant uncertainties about the carrying capacity of the planet. As a consequence, soil scientists are being challenged to provide regular assessments of soil conditions from local through to global scales. However, only a few countries have the necessary survey and monitoring programs to meet these new needs and existing global data sets are out-of-date. A particular issue is the clear demand for a new area-wide regional to global coverage with accurate, up-to-date, and spatially referenced soil information as expressed by the modeling scientific community, farmers and land users, and policy and decision makers. Soil spectroscopy from remote sensing observations based on studies from the laboratory scale to the airborne scale has been shown to be a proven method for the quantitative prediction of key soil surface properties in local areas for exposed soils in appropriate surface conditions such as low vegetation cover and low water content. With the upcoming launch of the next generation of hyperspectral satellite sensors in the next 3 to 5 years (EnMAP, HISUI, PRISMA, SHALOM), a great potential for the global mapping and monitoring of soil properties is appearing. Nevertheless, the capabilities to extend the soil properties current spectral modeling from local to regional scales are still to be demonstrated using robust methods. In particular, three central questions are at the forefront of research nowadays: a) methodological developments toward improved algorithms and operational tools for the extraction of soil properties, b) up scaling from the laboratory into space domain, and c) demonstration of the potential of upcoming satellite systems and expected accuracy of soil maps. In this study, airborne imaging spectroscopy data from several test sites are used to simulate EnMAP satellite images at 30 m scale. Then, different soil
Simulation of Magnetic Field Assisted Finishing (MFAF) Process Utilizing Smart MR Polishing Tool
NASA Astrophysics Data System (ADS)
Barman, Anwesa; Das, Manas
Magnetic field assisted finishing process is an advanced finishing process. This process is capable of producing nanometer level surface finish. In this process magnetic field is applied to control the finishing forces using magnetorheological polishing medium. In the current study, permanent magnet is used to provide the required magnetic field in the finishing zone. The working gap between the workpiece and the magnet is filled with MR fluid which is used as the polishing brush to remove surface undulations from the top surface of the workpiece. In this paper, the distribution of magnetic flux density on the workpiece surface and behaviour of MR polishing medium during finishing are analyzed using commercial finite element packages (Ansys Maxwell® and Comsol®). The role of magnetic force in the indentation of abrasive particles on the workpiece surface is studied. A two-dimensional simulation study of the steady, laminar, and incompressible MR fluid flow behaviour during finishing process is carried out. The material removal and surface roughness modelling of the finishing process are also presented. The indentation force by a single active abrasive particle on the workpiece surface is modelled during simulation. The velocity profile of MR fluid with and without application of magnetic field is plotted. It shows non-Newtonian property without application of magnetic field. After that the total material displacement due to one abrasive particle is plotted. The simulated roughness profile is in a good agreement with the experimental results. The conducted study will help in understanding the fluid behavior and the mechanism of finishing during finishing process. Also, the modelling and simulation of the process will help in achieving better finishing performance.
Quantifying the Accuracy of a Quad-Rotor Unmanned Aerial Vehicle as a Platform for Atmospheric Pressure, Temperature and Humidity Measurements near the Surface.
NASA Astrophysics Data System (ADS)
Guest, P. S.
Miniature multi-rotor unmanned aerial vehicles (UAVs) can be used to directly sample the lower atmosphere over land and over the ocean in the vicinity of ships or shorelines. These UAVs are generally inexpensive and easy to operate. The author used the InstantEye quad-rotor UAV, manufactured by Physical Sciences Inc., as a test platform for meteorological measurements. In this case, the atmospheric sensor was the RS-92 radiosonde manufactured by Vaisala Inc. The author will present quantitative results of several experiments performed over land at Camp Roberts, California in which the InstantEye with radiosonde sensors was flown alongside a calibrated meteorological tower, thus allowing the accuracy of the UAV measurements to be quantified. Measurements near the surface were most strongly affected by turbulent fluctuations during sunny, low wind days over a dry surface. The rotor wash (1) provides sensor aeration which counteracts radiation contamination effects (2) creates a dynamic pressure effect in lowest 1.5 m and (3) moves air from a different level (1 - 2 m). Horizontal motion of the UAV had little effect on the measurements. The accuracy of the mean temperature measurements in the surface layer during unstable conditions was estimated to be 0.2 to 0.3 C, if samples are taken for at least one minute, except in the lowest 1.5 m above the surface, where rotor wash effects brought hot surface air to the sensors, degrading the accuracy. Above the turbulent surface layer, the temperature measurements approached a 0.1 C accuracy.
Concrete Finisher Program. Apprenticeship Training.
ERIC Educational Resources Information Center
Alberta Learning, Edmonton. Apprenticeship and Industry Training.
This document presents information about the apprenticeship training program of Alberta, Canada, in general and the concrete finishing program in particular. The first part of the document discusses the following items: Alberta's apprenticeship and industry training system; the apprenticeship and industry training committee structure; local…
Magnetorheological finishing (MRF) in commercial precision optics manufacturing
NASA Astrophysics Data System (ADS)
Golini, Donald; Kordonski, William I.; Dumas, Paul; Hogan, Stephen J.
Finish polishing of highly precise optical surfaces is one of the most promising uses of magnetic fluids. We have taken the concept of magnetorheological finishing (MRF) from the laboratory to the optical fabrication shop floor. A commercial, computer numerically controlled (CNC) MRF machine, the Q22, has recently come on-line in optics companies to produce precision flat, spherical and aspheric optical components. MRF is a sub-aperture lap process that requires no specialized tooling, because the magnetically-stiffened abrasive fluid conforms to the local curvature of any arbitrarily shaped workpiece. MRF eliminates subsurface damage, smoothes rms microroughness to less than 1 nm, and corrects p-v surface figure errors to (lambda) /20 in minutes. Here the basic details of the MRF process are reviewed. MR fluid performance for soft and hard materials, the removal of asymmetric grinding errors and diamond turning marks, and examples of batch finishing of glass aspheres are also described.
Nano-accuracy measurements and the surface profiler by use of Monolithic Hollow Penta-Prism for precision mirror testing
NASA Astrophysics Data System (ADS)
Qian, Shinan; Wayne, Lewis; Idir, Mourad
We developed a Monolithic Hollow Penta-Prism Long Trace Profiler-NOM (MHPP-LTP-NOM) to attain nano-accuracy in testing plane- and near-plane-mirrors. A new developed Monolithic Hollow Penta-Prism (MHPP) combined with the advantages of PPLTP and autocollimator ELCOMAT of the Nano-Optic-Measuring Machine (NOM) is used to enhance the accuracy and stability of our measurements. Our precise system-alignment method by using a newly developed CCD position-monitor system (PMS) assured significant thermal stability and, along with our optimized noise-reduction analytic method, ensured nano-accuracy measurements. Herein we report our tests results; all errors are about 60 nrad rms or less in tests of plane- and near-plane- mirrors.
Accuracy and consistency of grass pollen identification by human analysts using electron micrographs of surface ornamentation1
Mander, Luke; Baker, Sarah J.; Belcher, Claire M.; Haselhorst, Derek S.; Rodriguez, Jacklyn; Thorn, Jessica L.; Tiwari, Shivangi; Urrego, Dunia H.; Wesseln, Cassandra J.; Punyasena, Surangi W.
• Premise of the study: Humans frequently identify pollen grains at a taxonomic rank above species. Grass pollen is a classic case of this situation, which has led to the development of computational methods for identifying grass pollen species. This paper aims to provide context for these computational methods by quantifying the accuracy and consistency of human identification. • Methods: We measured the ability of nine human analysts to identify 12 species of grass pollen using scanning electron microscopy images. These are the same images that were used in computational identifications. We have measured the coverage, accuracy, and consistency of each analyst, and investigated their ability to recognize duplicate images. • Results: Coverage ranged from 87.5% to 100%. Mean identification accuracy ranged from 46.67% to 87.5%. The identification consistency of each analyst ranged from 32.5% to 87.5%, and each of the nine analysts produced considerably different identification schemes. The proportion of duplicate image pairs that were missed ranged from 6.25% to 58.33%. • Discussion: The identification errors made by each analyst, which result in a decline in accuracy and consistency, are likely related to psychological factors such as the limited capacity of human memory, fatigue and boredom, recency effects, and positivity bias. PMID:25202649
Scanning Optical Head with Nontilted Reference Beam: Assuring Nanoradian Accuracy for a New Generation Surface Profiler in the Large-Slope Testing Range
Qian, Shinan
Nmore » anoradian Surface Profilers (NSPs) are required for state-of-the-art synchrotron radiation optics and high-precision optical measurements.ano-radian accuracy must be maintained in the large-angle test range. However, the beams' notable lateral motions during tests of most operating profilers, combined with the insufficiencies of their optical components, generate significant errors of ∼ 1 μ rad rms in the measurements. The solution to nano-radian accuracy for the new generation of surface profilers in this range is to apply a scanning optical head, combined with nontilted reference beam. I describe here my comparison of different scan modes and discuss some test results.« less
Recent advances in sub-aperture approaches to finishing and metrology
NASA Astrophysics Data System (ADS)
Tricard, Marc; Dumas, Paul; Forbes, Greg; DeMarco, Mike
This paper summarizes some of latest developments by QED Technologies (QED) in the field of high-precision polishing and metrology. Magneto-Rheological Finishing (MRF) is a deterministic sub-aperture polishing process that overcomes many of the fundamental limitations of traditional finishing. The MR fluid forms a polishing tool that is perfectly conformal and therefore can polish a variety of shapes, including flats, spheres, aspheres, prisms, and cylinders, with round or non-round apertures. Over the past several years, QED's Q22 family of polishing platforms, based on the MRF process, have demonstrated the ability to produce optical surfaces with accuracies better than 30 nm peak-to-valley (PV) and surface micro-roughness less than 0.5 nm rms on an ever-widening variety of optical glass, single crystal, and glass-ceramic materials. The MRF process facilitates the correction of the transmitted wavefront of single elements and/or entire systems, as well as enabling the inducement of specific desired wavefront characteristics (i.e., other than making surfaces perfectly flat or spherical), which is beneficial for applications such as phase correction or other freeform applications. QED's Sub-aperture Stitching Interferometer (SSI) complements MRF by extending the effective aperture, accuracy, resolution, and dynamic range of a phase-shifting interferometer. This workstation performs automated sub-aperture stitching measurements of spheres, flats, and mild aspheres. It combines a six-axis precision stage system, a commercial Fizeau interferometer, and specially developed software that automates measurement design, data acquisition, and the reconstruction of the full-aperture map of figure error. Aside from the correction of sub-aperture placement errors (such as tilts, optical power, and registration effects), the SSI software also accounts for reference-wave error, distortion, and other aberrations in the interferometer's imaging optics. By addressing these matters
Code of Federal Regulations, 2010 CFR
... 7 Agriculture 2 2010-01-01 2010-01-01 false Finish. 29.1017 Section 29.1017 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 92) § 29.1017 Finish. The reflectance factor in color perception. Finish indicates the sheen...
Code of Federal Regulations, 2010 CFR
... 7 Agriculture 2 2010-01-01 2010-01-01 false Finish. 29.3517 Section 29.3517 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Type 95) § 29.3517 Finish. The reflectance factor in color perception. Finish indicates the sheen...
27 CFR 25.231 - Finished beer.
Code of Federal Regulations, 2013 CFR
... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Finished beer. 25.231... OF THE TREASURY ALCOHOL BEER Beer Purchased From Another Brewer § 25.231 Finished beer. (a) A brewer may obtain beer in barrels and kegs, finished and ready for sale from another brewer. The...
27 CFR 25.231 - Finished beer.
Code of Federal Regulations, 2014 CFR
... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Finished beer. 25.231... OF THE TREASURY ALCOHOL BEER Beer Purchased From Another Brewer § 25.231 Finished beer. (a) A brewer may obtain beer in barrels and kegs, finished and ready for sale from another brewer. The...
27 CFR 25.231 - Finished beer.
Code of Federal Regulations, 2012 CFR
... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Finished beer. 25.231... OF THE TREASURY LIQUORS BEER Beer Purchased From Another Brewer § 25.231 Finished beer. (a) A brewer may obtain beer in barrels and kegs, finished and ready for sale from another brewer. The...
27 CFR 25.231 - Finished beer.
Code of Federal Regulations, 2010 CFR
... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Finished beer. 25.231... OF THE TREASURY LIQUORS BEER Beer Purchased From Another Brewer § 25.231 Finished beer. (a) A brewer may obtain beer in barrels and kegs, finished and ready for sale from another brewer. The...
27 CFR 25.231 - Finished beer.
Code of Federal Regulations, 2011 CFR
... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Finished beer. 25.231... OF THE TREASURY LIQUORS BEER Beer Purchased From Another Brewer § 25.231 Finished beer. (a) A brewer may obtain beer in barrels and kegs, finished and ready for sale from another brewer. The...
16 CFR 1509.8 - Construction and finishing.
Code of Federal Regulations, 2011 CFR
... REGULATIONS REQUIREMENTS FOR NON-FULL-SIZE BABY CRIBS § 1509.8 Construction and finishing. (a) All wood surfaces of non-full-size baby cribs shall be smooth and free from splinters. (b) All wood parts of non-full-size baby cribs shall be free from splits, cracks, or other defects that might lead to...
The Robotic Edge Finishing Laboratory
Loucks, C.S.; Selleck, C.B.
The Robotic Edge Finishing Laboratory at Sandia National Laboratories is developing four areas of technology required for automated deburring, chamfering, and blending of machined edges: (1) the automatic programming of robot trajectories and deburring processes using information derived from a CAD database, (2) the use of machine vision for locating the workpiece coupled with force control to ensure proper tool contact, (3) robotic deburring, blending, and machining of precision chamfered edges, and (4) in-process automated inspection of the formed edge. The Laboratory, its components, integration, and results from edge finishing experiments to date are described here. Also included is a discussion of the issues regarding implementation of the technology in a production environment. 24 refs., 17 figs.
SU-E-J-217: Accuracy Comparison Between Surface and Volumetric Registrations for Patient Setup of Head and Neck Radiation Therapy
Kim, Y; Li, R; Na, Y; Jenkins, C; Xing, L; Lee, R
Purpose: Optical surface imaging has been applied to radiation therapy patient setup. This study aims to investigate the accuracy of the surface registration of the optical surface imaging compared with that of the conventional method of volumetric registration for patient setup in head and neck radiation therapy. Methods: Clinical datasets of planning CT and treatment Cone Beam CT (CBCT) were used to compare the surface and volumetric registrations in radiation therapy patient setup. The Iterative Closest Points based on point-plane closest method was implemented for surface registration. We employed 3D Slicer for rigid volumetric registration of planning CT and treatment CBCT. 6 parameters of registration results (3 rotations and 3 translations) were obtained by the two registration methods, and the results were compared. Digital simulation tests in ideal cases were also performed to validate each registration method. Results: Digital simulation tests showed that both of the registration methods were accurate and robust enough to compare the registration results. In experiments with the actual clinical data, the results showed considerable deviation between the surface and volumetric registrations. The average root mean squared translational error was 2.7 mm and the maximum translational error was 5.2 mm. Conclusion: The deviation between the surface and volumetric registrations was considerable. Special caution should be taken in using an optical surface imaging. To ensure the accuracy of optical surface imaging in radiation therapy patient setup, additional measures are required. This research was supported in part by the KIST institutional program (2E24551), the Industrial Strategic technology development program (10035495) funded by the Ministry of Trade, Industry and Energy (MOTIE, KOREA), and the Radiation Safety Research Programs (1305033) through the Nuclear Safety and Security Commission, and the NIH (R01EB016777)
Accuracy of dynamic patient surface monitoring using a time-of-flight camera and B-spline modeling for respiratory motion characterization
NASA Astrophysics Data System (ADS)
Wentz, T.; Fayad, H.; Bert, J.; Pradier, O.; Clement, J. F.; Vourch, S.; Boussion, N.; Visvikis, D.
Time-of-flight (ToF) camera technology provides a real-time depth map of a scene with adequate frequency for the monitoring of physiological patient motion. However, dynamic surface motion estimation using a ToF camera is limited by issues such as the raw measurement accuracy and the absence of fixed anatomical landmarks. In this work we propose to overcome these limitations using surface modeling through B-splines. This approach was assessed in terms of both motion estimation accuracy and associated variability improvements using acquisitions of an anthropomorphic surface phantom for a range of observation distances (0.6-1.4 m). In addition, feasibility was demonstrated on patient acquisitions. Using the proposed B-spline modeling, the mean motion estimation error and associated repeatability with respect to the raw measurements decreased by a factor of 3. Significant correlation was found between patients' surfaces motion extracted using the proposed B-spline approach applied to the ToF data and the one extracted from synchronized 4D-CT acquisitions as the ground truth. ToF cameras represent a promising alternative for contact-less patient surface monitoring for respiratory motion synchronization or modeling in imaging and/or radiotherapy applications.
Planialtimetric Accuracy Evaluation of Digital Surface Model (dsm) and Digital Terrain Model (dtm) Obtained from Aerial Survey with LIDAR
NASA Astrophysics Data System (ADS)
Cruz, C. B. M.; Barros, R. S.; Rabaco, L. M. L.
It's noticed a significant increase in the development of orbital and airborne sensors that enable the extraction of three-dimensional data. Consequently, it's important the increment of studies about the quality of altimetric values derived from these sensors to verify if the improvements implemented in the acquisition of data may influence the results. In this context, as part of a larger project that aims to evaluate the accuracy of various sensors, this work aims to analysis the planialtimetric accuracy of DSM and DTM generated from an aerial survey with LIDAR, using as reference for the planimetric analysis of the orthophotos obtained. The project was developed for an area of São Sebastião city, located in the basin of the North Coast of São Paulo state. The area's relief is very steep, with a predominance of dense forest vegetation, typical of the Atlantic Forest. All points have been established in the field, with the use of GNSS of one frequency (L1) through static relative positioning, acquiring a minimum of 1,500 epochs, for a distance less than 20 km to the base. In this work it's considered the Brazilian standard specifications for classification of cartographic bases (PEC). The Brazilian company responsible for the aerial survey (LACTEC) gave the following products for analysis: point clouds in raw format (x, y, z) using orthometric heights; point clouds (first and last pulse) for each range of flight to verify systematic errors; DTM uniformly spaced, filtering small natural obstacles, buildings and vegetation, in Geotiff format; DSM also uniformly spaced, in Geotiff format; and the mosaic of georeferenced digital images. The analysis realized on products from the LIDAR indicated their adoption to the scales 1:2,000 (Class A for the orthophotos and Class B for the DTM) and 1:5,000 (class C for the DSM). There were no indications of trends in the results. The average error was 0.01 m. It's important that new areas with different topographic
Accuracy Assessment of Three-dimensional Surface Reconstructions of In vivo Teeth from Cone-beam Computed Tomography
Sang, Yan-Hui; Hu, Hong-Cheng; Lu, Song-He; Wu, Yu-Wei; Li, Wei-Ran; Tang, Zhi-Hui
Background: The accuracy of three-dimensional (3D) reconstructions from cone-beam computed tomography (CBCT) has been particularly important in dentistry, which will affect the effectiveness of diagnosis, treatment plan, and outcome in clinical practice. The aims of this study were to assess the linear, volumetric, and geometric accuracy of 3D reconstructions from CBCT and to investigate the influence of voxel size and CBCT system on the reconstructions results. Methods: Fifty teeth from 18 orthodontic patients were assigned to three groups as NewTom VG 0.15 mm group (NewTom VG; voxel size: 0.15 mm; n = 17), NewTom VG 0.30 mm group (NewTom VG; voxel size: 0.30 mm; n = 16), and VATECH DCTPRO 0.30 mm group (VATECH DCTPRO; voxel size: 0.30 mm; n = 17). The 3D reconstruction models of the teeth were segmented from CBCT data manually using Mimics 18.0 (Materialise Dental, Leuven, Belgium), and the extracted teeth were scanned by 3Shape optical scanner (3Shape A/S, Denmark). Linear and volumetric deviations were separately assessed by comparing the length and volume of the 3D reconstruction model with physical measurement by paired t-test. Geometric deviations were assessed by the root mean square value of the imposed 3D reconstruction and optical models by one-sample t-test. To assess the influence of voxel size and CBCT system on 3D reconstruction, analysis of variance (ANOVA) was used (α = 0.05). Results: The linear, volumetric, and geometric deviations were −0.03 ± 0.48 mm, −5.4 ± 2.8%, and 0.117 ± 0.018 mm for NewTom VG 0.15 mm group; −0.45 ± 0.42 mm, −4.5 ± 3.4%, and 0.116 ± 0.014 mm for NewTom VG 0.30 mm group; and −0.93 ± 0.40 mm, −4.8 ± 5.1%, and 0.194 ± 0.117 mm for VATECH DCTPRO 0.30 mm group, respectively. There were statistically significant differences between groups in terms of linear measurement (P < 0.001), but no significant difference in terms of volumetric measurement (P = 0.774). No statistically significant difference were
Accuracy Evaluation of a 3-Dimensional Surface Imaging System for Guidance in Deep-Inspiration Breath-Hold Radiation Therapy
Alderliesten, Tanja; Sonke, Jan-Jakob; Betgen, Anja; Honnef, Joeri; Vliet-Vroegindeweij, Corine van; Remeijer, Peter
Purpose: To investigate the applicability of 3-dimensional (3D) surface imaging for image guidance in deep-inspiration breath-hold radiation therapy (DIBH-RT) for patients with left-sided breast cancer. For this purpose, setup data based on captured 3D surfaces was compared with setup data based on cone beam computed tomography (CBCT). Methods and Materials: Twenty patients treated with DIBH-RT after breast-conserving surgery (BCS) were included. Before the start of treatment, each patient underwent a breath-hold CT scan for planning purposes. During treatment, dose delivery was preceded by setup verification using CBCT of the left breast. 3D surfaces were captured by a surface imaging system concurrently with the CBCT scan. Retrospectively, surface registrations were performed for CBCT to CT and for a captured 3D surface to CT. The resulting setup errors were compared with linear regression analysis. For the differences between setup errors, group mean, systematic error, random error, and 95% limits of agreement were calculated. Furthermore, receiver operating characteristic (ROC) analysis was performed. Results: Good correlation between setup errors was found: R{sup 2}=0.70, 0.90, 0.82 in left-right, craniocaudal, and anterior-posterior directions, respectively. Systematic errors were {<=}0.17 cm in all directions. Random errors were {<=}0.15 cm. The limits of agreement were -0.34-0.48, -0.42-0.39, and -0.52-0.23 cm in left-right, craniocaudal, and anterior-posterior directions, respectively. ROC analysis showed that a threshold between 0.4 and 0.8 cm corresponds to promising true positive rates (0.78-0.95) and false positive rates (0.12-0.28). Conclusions: The results support the application of 3D surface imaging for image guidance in DIBH-RT after BCS.
Precision Fabrication of a Large-Area Sinusoidal Surface Using a Fast-Tool-Servo Technique ─Improvement of Local Fabrication Accuracy─
NASA Astrophysics Data System (ADS)
Gao, Wei; Tano, Makoto; Araki, Takeshi; Kiyono, Satoshi
This paper describes a diamond turning fabrication system for a sinusoidal grid surface. The wavelength and amplitude of the sinusoidal wave in each direction are 100µm and 100nm, respectively. The fabrication system, which is based on a fast-tool-servo (FTS), has the ability to generate the angle grid surface over an area of φ 150mm. This paper focuses on the improvement of the local fabrication accuracy. The areas considered are each approximately 1 × 1mm, and can be imaged by an interference microscope. Specific fabrication errors of the manufacturing process, caused by the round nose geometry of the diamond cutting tool and the data digitization, are successfully identified by Discrete Fourier Transform of the microscope images. Compensation processes are carried out to reduce the errors. As a result, the fabrication errors in local areas of the angle grid surface are reduced by 1/10.
Functional finishes of stretch cotton fabrics.
Ibrahim, N A; Amr, A; Eid, B M; Almetwally, A A; Mourad, M M
Functionalized cotton cellulose/spandex woven fabrics with different structures namely plain (1/1), twill (2/2) and satin were produced. Factors affecting the imparted functional properties such as weave structure and constituents of the finishing formulations including ether or ester cross-linker and catalyst type, silicone-micro-emulsion, water/oil repellent, Ag-NP(,)s and TiO2-NP(,)s were studied. The treated fabrics were found to have easy care property together with one or more of the imparted functional properties such as soft-handle, water/oil repellence, antibacterial, UV-protection and self cleaning. The effectiveness of the imparted properties is not seriously affected even after 10 washing cycles. Surface modifications as well as the composition of certain samples were confirmed by SEM images and EDX spectra. Mode of interactions was also suggested. PMID:24053846
Impact of Calibrated Land Surface Model Parameters on the Accuracy and Uncertainty of Land-Atmosphere Coupling in WRF Simulations
NASA Technical Reports Server (NTRS)
Santanello, Joseph A., Jr.; Kumar, Sujay V.; Peters-Lidard, Christa D.; Harrison, Ken; Zhou, Shujia
Land-atmosphere (L-A) interactions play a critical role in determining the diurnal evolution of both planetary boundary layer (PBL) and land surface temperature and moisture budgets, as well as controlling feedbacks with clouds and precipitation that lead to the persistence of dry and wet regimes. Recent efforts to quantify the strength of L-A coupling in prediction models have produced diagnostics that integrate across both the land and PBL components of the system. In this study, we examine the impact of improved specification of land surface states, anomalies, and fluxes on coupled WRF forecasts during the summers of extreme dry (2006) and wet (2007) land surface conditions in the U.S. Southern Great Plains. The improved land initialization and surface flux parameterizations are obtained through the use of a new optimization and uncertainty estimation module in NASA's Land Information System (LIS-OPT/UE), whereby parameter sets are calibrated in the Noah land surface model and classified according to a land cover and soil type mapping of the observation sites to the full model domain. The impact of calibrated parameters on the a) spinup of the land surface used as initial conditions, and b) heat and moisture states and fluxes of the coupled WRF simulations are then assessed in terms of ambient weather and land-atmosphere coupling along with measures of uncertainty propagation into the forecasts. In addition, the sensitivity of this approach to the period of calibration (dry, wet, average) is investigated. Finally, tradeoffs of computational tractability and scientific validity, and the potential for combining this approach with satellite remote sensing data are also discussed.
Airborne Laser CO2 Column Measurements: Evaluation of Precision and Accuracy Under a Wide Range of Surface and Atmospheric Conditions
NASA Astrophysics Data System (ADS)
Browell, E. V.; Dobler, J. T.; Kooi, S. A.; Fenn, M. A.; Choi, Y.; Vay, S. A.; Harrison, F. W.; Moore, B.
This paper discusses the latest flight test results of a multi-frequency intensity-modulated (IM) continuous-wave (CW) laser absorption spectrometer (LAS) that operates near 1.57 μm for remote CO2 column measurements. This IM-LAS system is under development for a future space-based mission to determine the global distribution of regional-scale CO2 sources and sinks, which is the objective of the NASA Active Sensing of CO2 Emissions during Nights, Days, and Seasons (ASCENDS) mission. A prototype of the ASCENDS system, called the Multi-frequency Fiber Laser Lidar (MFLL), has been flight tested in eleven airborne campaigns since May 2005. This paper compares the most recent results obtained during the 2010 and 2011 UC-12 and DC-8 flight tests, where MFLL remote CO2 column measurements were evaluated against airborne in situ CO2 profile measurements traceable to World Meteorological Organization standards. The major change to the MFLL system in 2011 was the implementation of several different IM modes, which could be quickly changed in flight, to directly compare the precision and accuracy of MFLL CO2 measurements in each mode. The different IM modes that were evaluated included "fixed" IM frequencies near 50, 200, and 500 kHz; frequencies changed in short time steps (Stepped); continuously swept frequencies (Swept); and a pseudo noise (PN) code. The Stepped, Swept, and PN modes were generated to evaluate the ability of these IM modes to desensitize MFLL CO2 column measurements to intervening optically thin aerosols/clouds. MFLL was flown on the NASA Langley UC-12 aircraft in May 2011 to evaluate the newly implemented IM modes and their impact on CO2 measurement precision and accuracy, and to determine which IM mode provided the greatest thin cloud rejection (TCR) for the CO2 column measurements. Within the current hardware limitations of the MFLL system, the "fixed" 50 kHz results produced similar SNR values to those found previously. The SNR decreased as expected
A practical method for determining the accuracy of computer-generated holograms for off-axis aspheric surfaces
NASA Astrophysics Data System (ADS)
Li, Shijie; Liu, Bingcai; Tian, Ailing; Guo, Zhongda; Yang, Pengfei; Zhang, Jin
To design a computer-generated hologram (CGH) to measure off-axis aspheric surfaces with high precision, two different design methods are introduced: ray tracing and simulation using the Zemax software program. With ray tracing, after the discrete phase distribution is computed, a B-spline is used to obtain the phase function, and surface intersection is a useful method for determining the CGH fringe positions. In Zemax, the dummy glass method is an effective method for simulating CGH tests. Furthermore, the phase function can also be obtained from the Zernike Fringe Phase. The phase distributions and CGH fringe positions obtained from the two results were compared, and the two methods were determined to be in agreement. Finally, experimental outcomes were determined using the CGH test and autocollimation. The test result (PV=0.309λ, RMS=0.044λ) is the same as that determined by autocollimation (PV=0.330λ, RMS=0.044λ). Further analysis showed that the surface shape distribution and Zernike Fringe polynomial coefficient match well, indicating that the two design methods are correct and consistent and that the CGH test can measure off-axis aspheric surfaces with high precision.
Comparative evaluation of different thermally modified wood samples finishing with UV-curable and waterborne coatings
NASA Astrophysics Data System (ADS)
Herrera, René; Muszyńska, Monika; Krystofiak, Tomasz; Labidi, Jalel
Thermally modified wood has been developed as an industrial method to improve durability and dimensional stability of wood and thus extends the range of uses and service life of wood-based products. Despite the improvements gained by treatment, surface finishing using coatings prevents esthetical changes such as color degradation or occasional growth of mold adding protection in outdoor use and extending the service life of products. The wood finishing process was carried out with commercially available waterborne and UV-curable coatings on industrially modified at 192, 200, 212 °C and unmodified European ash (Fraxinus excelsior L.) wood, using an industrial rollers system and a laboratory brushing system. Changes caused by thermal treatment which could affect the surface finish were measured and compared with control samples, such as water uptake, wettability and acidity. Following the wood finishing, surface properties and esthetic changes were evaluated; as well as the coatings performance. Thermally modified wood presented improved adherence compared with unmodified wood with a significant improvement in samples modified at 212 °C, which also present the highest hardness when UV-cured. Finishes with UV-curing maintain the hydrophobic effect of thermally modified wood, whereas waterborne finishes increase the surface wettability. Thermal modification did not negatively influence on the elastic properties of the coated substrate and thus allows this material to be finished with different coating systems in the same conditions as unmodified wood.
Estimating river discharge from the Surface Water and Ocean Topography mission: Estimated accuracy of approaches based on Manning's equation
NASA Astrophysics Data System (ADS)
Clark, E.; Durand, M. T.; Moller, D.; Biancamaria, S.; Andreadis, K.; Lettenmaier, D. P.; Alsdorf, D.; Mognard, N. M.
Freshwater is vital for life on Earth; however, its distribution and variability is poorly understood. This is due, in part, to physical, political, and economic constraints on the placement and maintenance of observation stations. In addition, most in situ observations are fundamentally one-dimensional in nature, thereby missing the complexities of, for example, floodplain flow. The upcoming Surface Water Ocean Topography (SWOT) mission will provide global swath satellite coverage of surface water. In particular, SWOT will measure water surface elevations (WSE), water surface slope, and the areal extent of lakes, wetlands, reservoirs, floodplains, and rivers globally (between 78° N and 78° S latitude). Measurements at each location will be made at least twice in a 22-day repeat period. Ultimately, SWOT should provide enough information from which to estimate instantaneous river discharge for moderately large rivers (at least 100 m wide). Although multiple algorithms of varying complexity are being developed for river discharge estimation, a simple approach is the application of Manning's equation. SWOT will directly measure water surface slope to an accuracy (1σ) of 1 cm/km, averaged over 10 km reaches. In addition, SWOT will measure WSE, related to changes in river depth, to an accuracy (1σ) of 10 cm, when averaged over river reaches of 1 km2 area. The impact of these errors, as well as potential errors in variables that will need to be estimated from SWOT or provided from ancillary sources (river width, Manning's roughness, initial river depth), on discharge estimates are evaluated using a collection of reach-averaged channel properties of rivers in New Zealand, the Amazon, and the United States. Because estimated errors in river width, Manning's roughness, and initial river depth are likely to change as retrieval algorithms improve, a range of potential errors are evaluated, and maximum allowable errors that would allow a goal of 20% maximum discharge
Laser-assisted pre-finishing of optical ceramic materials
NASA Astrophysics Data System (ADS)
Rozzi, Jay C.; Clavier, Odile H.; Barton, Michael D.
At Creare, we are developing a laser-assisted, pre-finishing system that enables the single-point diamond turning of super-hard ceramics into hemispheres, ogives, and other shapes that are ready for final optical finishing. Currently, super-hard ceramic materials cannot be affordably processed due to the low material removal rates and the high amount of sub-surface damage associated with current processes. Our innovation uses a low-power, far-infrared laser to heat, but not ablate, a thin layer of material prior to its removal. By heating the ceramic material, plastic-like deformation at the cutting edge is fostered by high-temperature dislocation motion. In doing so, the cutting forces are reduced which enables attendant reductions in tool wear, surface and sub-surface damage, and processing time. Our paper will summarize the development of our innovation, describe the process, discuss the machine tool, and review the latest results.
Accuracy of near-surface aerosol extinction determined from columnar aerosol optical depth measurements in Reno, NV, USA
NASA Astrophysics Data System (ADS)
Loría-Salazar, S. Marcela; Arnott, W. Patrick; Moosmüller, Hans
The aim of the present work is a detailed analysis of aerosol columnar optical depth as a tool to determine near-surface aerosol extinction in Reno, Nevada, USA, during the summer of 2012. Ground and columnar aerosol optical properties were obtained by use of in situ Photoacoustic and Integrated Nephelometer and Cimel CE-318 Sun photometer instruments, respectively. Both techniques showed that seasonal weather changes and fire plumes had enormous influence on local aerosol optics. The apparent optical height followed the shape but not magnitude of the development of the convective boundary layer when fire conditions were not present. Back trajectory analysis demonstrated that a local flow known as the Washoe Zephyr circulation often induced aerosol transport from Northern California over the Sierra Nevada Mountains that increased the aerosol optical depth at 500 nm during afternoons when compared with mornings. Aerosol fine mode fraction indicated that afternoon aerosols in June and July and fire plumes in August were dominated by submicron particles, suggesting upwind urban plume biogenically enhanced evolution toward substantial secondary aerosol formation. This fine particle optical depth was inferred to be beyond the surface, thereby complicating use of remote sensing measurements for near-ground aerosol extinction measurements. It is likely that coarse mode depletes fine mode aerosol near the surface by coagulation and condensation of precursor gases.
Accuracies of facial soft tissue depth means for estimating ground truth skin surfaces in forensic craniofacial identification.
Stephan, Carl N
Facial soft tissue thickness means have long been used as a proxy to estimate the soft tissue envelope, over the skull, in craniofacial identification. However, estimation errors of these statistics are not well understood, making casework selection of the best performing estimation models impossible and overarching method accuracies controversial. To redress this situation, residuals between predicted and ground truth values were calculated in two experiments: (1) for 27 suites of means drawn from 10 recently published studies, all examining the same 10 landmarks (N ≥ 3051), and tested against six independent raw datasets of contemporary living adults (N = 797); and (2) pairwise tests of the above six, and five other, raw datasets (N = 1063). In total, 380 out-of-sample tests of 416 arithmetic means were conducted across 11 independent samples. Experiment 1 produced an overarching mean absolute percentage error (MAE) of 29% and a standard error of the estimate (S(est)) of 2.7 mm. Experiment 2 yielded MAE of 32% and S(est) of 2.8 mm. In any instance, MAE was always ≥20% of the ground truth value. The overarching 95% limits of the error, for contemporary samples, was large (11.4 mm). CT-derived means from South Korean males and Black South African females routinely performed well across the test samples and produced the smallest errors of any tests (but did so for Black American male reference samples). Sample-specific statistics thereby performed poorly despite discipline esteem. These results—and the practice of publishing means without prior model validation—demand major reforms in the field. PMID:25394746
Survey mirrors and lenses and their required surface accuracy. Volume 1. Technical report. Final report for September 15, 1978-December 1, 1979
Beesing, M. E.; Buchholz, R. L.; Evans, R. A.; Jaminski, R. W.; Mathur, A. K.; Rausch, R. A.; Scarborough, S.; Smith, G. A.; Waldhauer, D. J.
An investigation of the optical performance of a variety of concentrating solar collectors is reported. The study addresses two important issues: the accuracy of reflective or refractive surfaces required to achieve specified performance goals, and the effect of environmental exposure on the performance concentrators. To assess the importance of surface accuracy on optical performance, 11 tracking and nontracking concentrator designs were selected for detailed evaluation. Mathematical models were developed for each design and incorporated into a Monte Carlo ray trace computer program to carry out detailed calculations. Results for the 11 concentrators are presented in graphic form. The models and computer program are provided along with a user's manual. A survey data base was established on the effect of environmental exposure on the optical degradation of mirrors and lenses. Information on environmental and maintenance effects was found to be insufficient to permit specific recommendations for operating and maintenance procedures, but the available information is compiled and reported and does contain procedures that other workers have found useful.
Enhancing the estimation accuracy in low state-of-charge area: A novel onboard battery model through surface state of charge determination
NASA Astrophysics Data System (ADS)
Ouyang, Minggao; Liu, Guangming; Lu, Languang; Li, Jianqiu; Han, Xuebing
In order to predict the battery remaining discharge energy in electric vehicles, an accurate onboard battery model is needed for the terminal voltage and state of charge (SOC) estimation in the whole SOC range. However, the commonly-used equivalent circuit model (ECM) provides limited accuracy in low-SOC area, which hinders the full use of battery remaining energy. To improve the low-SOC-area performance, this paper presents an extended equivalent circuit model (EECM) based on single-particle electrochemical model. In EECM, the solid-phase diffusion process is represented by the SOC difference within the electrode particle, and the terminal voltage is determined by the surface SOC (SOCsurf) representing the lithium concentration at the particle surface. Based on a large-format lithium-ion battery, the voltage estimation performance of ECM and EECM is compared in the entire SOC range (0-100%) under different load profiles, and the genetic algorithm is implemented in model parameterization. Results imply that the EECM could reduce the voltage error by more than 50% in low-SOC area. The SOC estimation accuracy is then discussed employing the extended Kalman filter, and the EECM also exhibits significant advantage. As a result, the EECM is very potential for real-time applications to enhance the voltage and SOC estimation precision especially for low-SOC cases.
Roughness Analysis on Composite Materials (Microfilled, Nanofilled and Silorane) After Different Finishing and Polishing Procedures.
Pettini, Francesco; Corsalini, Massimo; Savino, Maria Grazia; Stefanachi, Gianluca; Venere, Daniela Di; Pappalettere, Carmine; Monno, Giuseppe; Boccaccio, Antonio
The finishing and polishing of composite materials affect the restoration lifespan. The market shows a variety of finishing and polishing procedures and the choice among them is conditioned by different factors such as the resulting surface roughness. In the present study, 156 samples were realized with three composite materials, -microfilled, nanofilled and silorane-, and treated with different finishing and polishing procedures. Profilometric analyses were carried out on the samples' surface, the measured roughness values were submitted to statistical analysis. A complete factorial plan was drawn up and two-way analysis of variance (ANOVA) was carried out to investigate whether the following factors affect the values of roughness: (i) material; (ii) polishing/finishing procedure. Tukey post-hoc test was also conducted to evaluate any statistically significant differences between the material/procedure combinations. The results show that the tested materials do not affect the resulting surface quality but roughness values depend on the finishing/polishing procedure adopted. The procedures that involve: (a) the finishing with medium Sof-Lex discs and (b) the finishing with two tungsten carbide multi-blade milling cutters Q series and UF series are those that allow the lowest values of roughness to be obtained. PMID:26734113
Study on ultra-precision magnetic abrasive finishing process using low frequency alternating magnetic field
NASA Astrophysics Data System (ADS)
Wu, Jinzhong; Zou, Yanhua; Sugiyama, Hitoshi
We proposed a new ultra-precision magnetic abrasive finishing (MAF) process using low frequency alternating magnetic field in this paper. Magnetic cluster themselves may produce the up and down movement change under alternating magnetic force. The movement may not only promote the dispersion of micro-magnetic particles, but also improve stirring effect and cross-cutting effects of the abrasives, achieving circulation and update to ensure the stability of grinding tools. This process is considered to be able to efficiently apply in ultra-precision finishing of plane and complicated micro-surfaces. In this study, we investigated the effects of alternating magnetic field on magnetic field distribution, finishing force and abrasive behavior. Furthermore, a set of experimental devices have been designed for finishing SUS304 stainless steel plate. The present work is aimed at understanding finishing particularity of this process and studying impacts of important process parameters namely grinding fluid, rotational speed of magnetic pole, current frequency on change in finish surface and material removal. Experimental results indicate that the process can realize ultra-precision finishing of plane by using oily grinding fluid. In the present research, the surface roughness of SUS304 stainless steel plate was improved from 240.24 nm to 4.38 nm by this process.
Roughness Analysis on Composite Materials (Microfilled, Nanofilled and Silorane) After Different Finishing and Polishing Procedures
Pettini, Francesco; Corsalini, Massimo; Savino, Maria Grazia; Stefanachi, Gianluca; Venere, Daniela Di; Pappalettere, Carmine; Monno, Giuseppe; Boccaccio, Antonio
The finishing and polishing of composite materials affect the restoration lifespan. The market shows a variety of finishing and polishing procedures and the choice among them is conditioned by different factors such as the resulting surface roughness. In the present study, 156 samples were realized with three composite materials, -microfilled, nanofilled and silorane-, and treated with different finishing and polishing procedures. Profilometric analyses were carried out on the samples' surface, the measured roughness values were submitted to statistical analysis. A complete factorial plan was drawn up and two-way analysis of variance (ANOVA) was carried out to investigate whether the following factors affect the values of roughness: (i) material; (ii) polishing/finishing procedure. Tukey post-hoc test was also conducted to evaluate any statistically significant differences between the material/procedure combinations. The results show that the tested materials do not affect the resulting surface quality but roughness values depend on the finishing/polishing procedure adopted. The procedures that involve: (a) the finishing with medium Sof-Lex discs and (b) the finishing with two tungsten carbide multi-blade milling cutters Q series and UF series are those that allow the lowest values of roughness to be obtained. PMID:26734113
New finishing possibilities for producing durable multifunctional cotton/wool and viscose/wool blended fabrics.
Ibrahim, N A; El-Zairy, M R; Eid, B M; El-Zairy, E M R; Emam, E M
This research work focuses on the development of a one-bath functional finishing procedure for imparting durable multifunctional properties such as easy care, soft-hand, antibacterial and/or ultra violet (UV) protection to cotton/wool and viscose/wool blends using diverse finishing combinations and formulations. In this study finishing agents such as reactant resin, silicon softeners, 4-hydroxybenzophenone, triclosan, and pigment colorant were selected using magnesium chloride/citric acid as a mixed catalyst and the pad-dry microwave fixation technique. The results reveal that enhancement in the imparted functional properties are governed by type of the finished substrate as well as nature and concentration of finishing formulation components. The finished fabrics still retained high level of functionalities even after 15 consecutive laundering. Surface morphology and composition of selected samples were investigated using scan electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDX) analysis. The mode of interactions was also investigated. Practical applications for multifunctionlization of cellulose/wool blended fabrics are possible using these sorts of proper finishing formulations and unique finishing application method. PMID:25563959
Metal Finishing Facility Risk Screening Tool (Mffrst)
The Metal Finishing Facility Risk Screening Tool (MFFRST) is a user-friendly pc-based computer tool which allows an individual to evaluate the potential exposures and health risks to workers and nearby residents from emissions from individual metal finishing facilities. Emission...
Code of Federal Regulations, 2010 CFR
... 25 Indians 2 2010-04-01 2010-04-01 false Finish. 301.8 Section 301.8 Indians INDIAN ARTS AND CRAFTS BOARD, DEPARTMENT OF THE INTERIOR NAVAJO, PUEBLO, AND HOPI SILVER AND TURQUOISE PRODUCTS; STANDARDS § 301.8 Finish. All silver is to be hand...
Code of Federal Regulations, 2014 CFR
... 25 Indians 2 2014-04-01 2014-04-01 false Finish. 301.8 Section 301.8 Indians INDIAN ARTS AND CRAFTS BOARD, DEPARTMENT OF THE INTERIOR NAVAJO, PUEBLO, AND HOPI SILVER AND TURQUOISE PRODUCTS; STANDARDS § 301.8 Finish. All silver is to be hand...
Code of Federal Regulations, 2012 CFR
... 25 Indians 2 2012-04-01 2012-04-01 false Finish. 301.8 Section 301.8 Indians INDIAN ARTS AND CRAFTS BOARD, DEPARTMENT OF THE INTERIOR NAVAJO, PUEBLO, AND HOPI SILVER AND TURQUOISE PRODUCTS; STANDARDS § 301.8 Finish. All silver is to be hand...
Code of Federal Regulations, 2013 CFR
... 25 Indians 2 2013-04-01 2013-04-01 false Finish. 301.8 Section 301.8 Indians INDIAN ARTS AND CRAFTS BOARD, DEPARTMENT OF THE INTERIOR NAVAJO, PUEBLO, AND HOPI SILVER AND TURQUOISE PRODUCTS; STANDARDS § 301.8 Finish. All silver is to be hand...
Code of Federal Regulations, 2011 CFR
... 25 Indians 2 2011-04-01 2011-04-01 false Finish. 301.8 Section 301.8 Indians INDIAN ARTS AND CRAFTS BOARD, DEPARTMENT OF THE INTERIOR NAVAJO, PUEBLO, AND HOPI SILVER AND TURQUOISE PRODUCTS; STANDARDS § 301.8 Finish. All silver is to be hand...
The Metal Finishing Facility Pollution Tool (MFFPPT) is being developed to allow the metal finishing industry an easy method to evaluate potential pollution prevention options. In order to reduce the quantity of pollutants generated by a process, the sources of pollutants within ...
Effect of Flexural Rigidity of Tool on Machining Accuracy during Microgrooving by Ultrasonic Vibration Cutting Method
NASA Astrophysics Data System (ADS)
Furusawa, Toshiaki
It is necessary to form fine holes and grooves by machining in the manufacture of equipment in the medical or information field and the establishment of such a machining technology is required. In micromachining, the use of the ultrasonic vibration cutting method is expected and examined. In this study, I experimentally form microgrooves in stainless steel SUS304 by the ultrasonic vibration cutting method and examine the effects of the shape and material of the tool on the machining accuracy. As a result, the following are clarified. The evaluation of the machining accuracy of the straightness of the finished surface revealed that there is an optimal rake angle of the tools related to the increase in cutting resistance as a result of increases in work hardening and the cutting area. The straightness is improved by using a tool with low flexural rigidity. In particular, Young's modulus more significantly affects the cutting accuracy than the shape of the tool.
JSC Metal Finishing Waste Minimization Methods
NASA Technical Reports Server (NTRS)
Sullivan, Erica
THe paper discusses the following: Johnson Space Center (JSC) has achieved VPP Star status and is ISO 9001 compliant. The Structural Engineering Division in the Engineering Directorate is responsible for operating the metal finishing facility at JSC. The Engineering Directorate is responsible for $71.4 million of space flight hardware design, fabrication and testing. The JSC Metal Finishing Facility processes flight hardware to support the programs in particular schedule and mission critical flight hardware. The JSC Metal Finishing Facility is operated by Rothe Joint Venture. The Facility provides following processes: anodizing, alodining, passivation, and pickling. JSC Metal Finishing Facility completely rebuilt in 1998. Total cost of $366,000. All new tanks, electrical, plumbing, and ventilation installed. Designed to meet modern safety, environmental, and quality requirements. Designed to minimize contamination and provide the highest quality finishes.
Transferability and accuracy by combining dispersionless density functional and incremental post-Hartree-Fock theories: Noble gases adsorption on coronene/graphene/graphite surfaces
Lara-Castells, María Pilar de Bartolomei, Massimiliano; Mitrushchenkov, Alexander O.; Stoll, Hermann
The accuracy and transferability of the electronic structure approach combining dispersionless density functional theory (DFT) [K. Pernal et al., Phys. Rev. Lett. 103, 263201 (2009)] with the method of increments [H. Stoll, J. Chem. Phys. 97, 8449 (1992)], are validated for the interaction between the noble-gas Ne, Ar, Kr, and Xe atoms and coronene/graphene/graphite surfaces. This approach uses the method of increments for surface cluster models to extract intermonomer dispersion-like (2- and 3-body) correlation terms at coupled cluster singles and doubles and perturbative triples level, while periodic dispersionless density functionals calculations are performed to estimate the sum of Hartree-Fock and intramonomer correlation contributions. Dispersion energy contributions are also obtained using DFT-based symmetry-adapted perturbation theory [SAPT(DFT)]. An analysis of the structure of the X/surface (X = Ne, Ar, Kr, and Xe) interaction energies shows the excellent transferability properties of the leading intermonomer correlation contributions across the sequence of noble-gas atoms, which are also discussed using the Drude oscillator model. We further compare these results with van der Waals-(vdW)-corrected DFT-based approaches. As a test of accuracy, the energies of the low-lying nuclear bound states supported by the laterally averaged X/graphite potentials (X = {sup 3}He, {sup 4}He, Ne, Ar, Kr, and Xe) are calculated and compared with the best estimations from experimental measurements and an atom-bond potential model using the ab initio-assisted fine-tuning of semiempirical parameters. The bound-state energies determined differ by less than 6–7 meV (6%) from the atom-bond potential model. The crucial importance of including incremental 3-body dispersion-type terms is clearly demonstrated, showing that the SAPT(DFT) approach effectively account for these terms. With the deviations from the best experimental-based estimations smaller than 2.3 meV (1.9%), the
Transferability and accuracy by combining dispersionless density functional and incremental post-Hartree-Fock theories: Noble gases adsorption on coronene/graphene/graphite surfaces.
de Lara-Castells, María Pilar; Bartolomei, Massimiliano; Mitrushchenkov, Alexander O; Stoll, Hermann
The accuracy and transferability of the electronic structure approach combining dispersionless density functional theory (DFT) [K. Pernal et al., Phys. Rev. Lett. 103, 263201 (2009)] with the method of increments [H. Stoll, J. Chem. Phys. 97, 8449 (1992)], are validated for the interaction between the noble-gas Ne, Ar, Kr, and Xe atoms and coronene/graphene/graphite surfaces. This approach uses the method of increments for surface cluster models to extract intermonomer dispersion-like (2- and 3-body) correlation terms at coupled cluster singles and doubles and perturbative triples level, while periodic dispersionless density functionals calculations are performed to estimate the sum of Hartree-Fock and intramonomer correlation contributions. Dispersion energy contributions are also obtained using DFT-based symmetry-adapted perturbation theory [SAPT(DFT)]. An analysis of the structure of the X/surface (X = Ne, Ar, Kr, and Xe) interaction energies shows the excellent transferability properties of the leading intermonomer correlation contributions across the sequence of noble-gas atoms, which are also discussed using the Drude oscillator model. We further compare these results with van der Waals-(vdW)-corrected DFT-based approaches. As a test of accuracy, the energies of the low-lying nuclear bound states supported by the laterally averaged X/graphite potentials (X = (3)He, (4)He, Ne, Ar, Kr, and Xe) are calculated and compared with the best estimations from experimental measurements and an atom-bond potential model using the ab initio-assisted fine-tuning of semiempirical parameters. The bound-state energies determined differ by less than 6-7 meV (6%) from the atom-bond potential model. The crucial importance of including incremental 3-body dispersion-type terms is clearly demonstrated, showing that the SAPT(DFT) approach effectively account for these terms. With the deviations from the best experimental-based estimations smaller than 2.3 meV (1.9%), the accuracy of
Shear Stress in Magnetorheological FInishing for Glasses
Miao, C.; Shafrir, S.N.; Lambropoulos, J.C.; Mici, J.; Jacobs, S.D.
We report in situ, simultaneous measurements of both drag and normal forces in magnetorheological finishing (MRF) for what is believed to be the first time, using a spot taking machine (STM) as a test bed to take MRF spots on stationary parts. The measurements are carried out over the entire area where material is being removed, i.e., the projected area of the MRF removal function/spot on the part surface, using a dual force sensor. This approach experimentally addresses the mechanisms governing material removal in MRF for optical glasses in terms of the hydrodynamic pressure and shear stress, applied by the hydrodynamic flow of magnetorheological fluid at the gap between the part surface and the STM wheel. This work demonstrates that the volumetric removal rate shows a positive linear dependence on shear stress. Shear stress exhibits a positive linear dependence on a material figure of merit that depends upon Young's modulus, fracture toughness, and hardness. A modified Preston's equation is proposed that better estimates MRF material removal rate for optical glasses by incorporating mechanical properties, shear stress, and velocity.
Shear stress in magnetorheological finishing for glasses.
Miao, Chunlin; Shafrir, Shai N; Lambropoulos, John C; Mici, Joni; Jacobs, Stephen D
We report in situ, simultaneous measurements of both drag and normal forces in magnetorheological finishing (MRF) for what is believed to be the first time, using a spot taking machine (STM) as a test bed to take MRF spots on stationary parts. The measurements are carried out over the entire area where material is being removed, i.e., the projected area of the MRF removal function/spot on the part surface, using a dual force sensor. This approach experimentally addresses the mechanisms governing material removal in MRF for optical glasses in terms of the hydrodynamic pressure and shear stress, applied by the hydrodynamic flow of magnetorheological fluid at the gap between the part surface and the STM wheel. This work demonstrates that the volumetric removal rate shows a positive linear dependence on shear stress. Shear stress exhibits a positive linear dependence on a material figure of merit that depends upon Young's modulus, fracture toughness, and hardness. A modified Preston's equation is proposed that better estimates MRF material removal rate for optical glasses by incorporating mechanical properties, shear stress, and velocity. PMID:19412219
Influence of the training set on the accuracy of surface EMG classification in dynamic contractions for the control of multifunction prostheses
Background For high usability, myo-controlled devices require robust classification schemes during dynamic contractions. Therefore, this study investigates the impact of the training data set in the performance of several pattern recognition algorithms during dynamic contractions. Methods A 9 class experiment was designed involving both static and dynamic situations. The performance of various feature extraction methods and classifiers was evaluated in terms of classification accuracy. Results It is shown that, combined with a threshold to detect the onset of the contraction, current pattern recognition algorithms used on static conditions provide relatively high classification accuracy also on dynamic situations. Moreover, the performance of the pattern recognition algorithms tested significantly improved by optimizing the choice of the training set. Finally, the results also showed that rather simple approaches for classification of time domain features provide results comparable to more complex classification methods of wavelet features. Conclusions Non-stationary surface EMG signals recorded during dynamic contractions can be accurately classified for the control of multi-function prostheses. PMID:21554700
High-Precision Surface Inspection: Uncertainty Evaluation within an Accuracy Range of 15μm with Triangulation-based Laser Line Scanners
NASA Astrophysics Data System (ADS)
Dupuis, Jan; Kuhlmann, Heiner
Triangulation-based range sensors, e.g. laser line scanners, are used for high-precision geometrical acquisition of free-form surfaces, for reverse engineering tasks or quality management. In contrast to classical tactile measuring devices, these scanners generate a great amount of 3D-points in a short period of time and enable the inspection of soft materials. However, for accurate measurements, a number of aspects have to be considered to minimize measurement uncertainties. This study outlines possible sources of uncertainties during the measurement process regarding the scanner warm-up, the impact of laser power and exposure time as well as scanner's reaction to areas of discontinuity, e.g. edges. All experiments were performed using a fixed scanner position to avoid effects resulting from imaging geometry. The results show a significant dependence of measurement accuracy on the correct adaption of exposure time as a function of surface reflectivity and laser power. Additionally, it is illustrated that surface structure as well as edges can cause significant systematic uncertainties.
Influence of Head Motion on the Accuracy of 3D Reconstruction with Cone-Beam CT: Landmark Identification Errors in Maxillofacial Surface Model
Song, Jin-Myoung; Cho, Jin-Hyoung
Purpose The purpose of this study was to investigate the influence of head motion on the accuracy of three-dimensional (3D) reconstruction with cone-beam computed tomography (CBCT) scan. Materials and Methods Fifteen dry skulls were incorporated into a motion controller which simulated four types of head motion during CBCT scan: 2 horizontal rotations (to the right/to the left) and 2 vertical rotations (upward/downward). Each movement was triggered to occur at the start of the scan for 1 second by remote control. Four maxillofacial surface models with head motion and one control surface model without motion were obtained for each skull. Nine landmarks were identified on the five maxillofacial surface models for each skull, and landmark identification errors were compared between the control model and each of the models with head motion. Results Rendered surface models with head motion were similar to the control model in appearance; however, the landmark identification errors showed larger values in models with head motion than in the control. In particular, the Porion in the horizontal rotation models presented statistically significant differences (P < .05). Statistically significant difference in the errors between the right and left side landmark was present in the left side rotation which was opposite direction to the scanner rotation (P < .05). Conclusions Patient movement during CBCT scan might cause landmark identification errors on the 3D surface model in relation to the direction of the scanner rotation. Clinicians should take this into consideration to prevent patient movement during CBCT scan, particularly horizontal movement. PMID:27065238
Superfinished Surfaces for Power Transfer Systems Improvement
NASA Technical Reports Server (NTRS)
Niskanen, Paul; Manesh, Ali; Warren, Alford; Krantz, Timothy
The continuous demands for high performance and lightweight power train systems resulted in requirements for higher power density gearing systems. However, increasing the load bearing capacity of the gear teeth, without increasing size, places stringent requirements upon metallurgy, dimensional control, and surface finish of the final products. In order to operate the mating parts near the upper bounds of their theoretical design envelope, manufacturing processes are required that are capable of improving the fatigue life and load bearing capacity of precision parts, while producing the required geometric accuracy. Results of the recent experimental studies indicate that the super finishing process is able to achieve these goals. This paper will review the results of our continuing evaluation of the super finish process as applied to aerospace gearing. Two separate evaluations were performed on gears to examine the effects of super finishing on resistance to both pitting and contact fatigue. For the reported experiments, both conventional and super finished test gears were simultaneously manufactured using the same process and the same heat lot of materials. This paper will also provide a brief description of the manufacturing technology used to achieve the results and will compare the results with other published data. In addition, this paper presents a couple of off-the-shelf manufacturing technologies that have been successfully used to super finish test specimens and will provide a glimpse of other emerging super finishing technologies. This is a US Army Manufacturing Technology project. The project was sponsored by the Aviation and Missiles Command (AMCOM) and was being managed and conducted by IIT Research Institute.
Automatic tool path generation for finish machining
Kwok, Kwan S.; Loucks, C.S.; Driessen, B.J.
A system for automatic tool path generation was developed at Sandia National Laboratories for finish machining operations. The system consists of a commercially available 5-axis milling machine controlled by Sandia developed software. This system was used to remove overspray on cast turbine blades. A laser-based, structured-light sensor, mounted on a tool holder, is used to collect 3D data points around the surface of the turbine blade. Using the digitized model of the blade, a tool path is generated which will drive a 0.375 inch diameter CBN grinding pin around the tip of the blade. A fuzzified digital filter was developed to properly eliminate false sensor readings caused by burrs, holes and overspray. The digital filter was found to successfully generate the correct tool path for a blade with intentionally scanned holes and defects. The fuzzified filter improved the computation efficiency by a factor of 25. For application to general parts, an adaptive scanning algorithm was developed and presented with simulation results. A right pyramid and an ellipsoid were scanned successfully with the adaptive algorithm.
Effort required to finish shotgun-generated genome sequences differs significantly among vertebrates
Background The approaches for shotgun-based sequencing of vertebrate genomes are now well-established, and have resulted in the generation of numerous draft whole-genome sequence assemblies. In contrast, the process of refining those assemblies to improve contiguity and increase accuracy (known as 'sequence finishing') remains tedious, labor-intensive, and expensive. As a result, the vast majority of vertebrate genome sequences generated to date remain at a draft stage. Results To date, our genome sequencing efforts have focused on comparative studies of targeted genomic regions, requiring sequence finishing of large blocks of orthologous sequence (average size 0.5-2 Mb) from various subsets of 75 vertebrates. This experience has provided a unique opportunity to compare the relative effort required to finish shotgun-generated genome sequence assemblies from different species, which we report here. Importantly, we found that the sequence assemblies generated for the same orthologous regions from various vertebrates show substantial variation with respect to misassemblies and, in particular, the frequency and characteristics of sequence gaps. As a consequence, the work required to finish different species' sequences varied greatly. Application of the same standardized methods for finishing provided a novel opportunity to "assay" characteristics of genome sequences among many vertebrate species. It is important to note that many of the problems we have encountered during sequence finishing reflect unique architectural features of a particular vertebrate's genome, which in some cases may have important functional and/or evolutionary implications. Finally, based on our analyses, we have been able to improve our procedures to overcome some of these problems and to increase the overall efficiency of the sequence-finishing process, although significant challenges still remain. Conclusion Our findings have important implications for the eventual finishing of the draft whole
This document provides information on the regulations affecting hazardous wastes discharged by metal finishers. opics included are: impact of RCRA regulations on both small and large generators; "delisting" of a specific facility waste from hazardous waste regulation; land dispos...
On the accuracy of explicitly correlated methods to generate potential energy surfaces for scattering calculations and clustering: application to the HCl-He complex.
Ajili, Yosra; Hammami, Kamel; Jaidane, Nejm Eddine; Lanza, Mathieu; Kalugina, Yulia N; Lique, François; Hochlaf, Majdi
We closely compare the accuracy of multidimensional potential energy surfaces (PESs) generated by the recently developed explicitly correlated coupled cluster (CCSD(T)-F12) methods in connection with the cc-pVXZ-F12 (X = D, T) and aug-cc-pVTZ basis sets and those deduced using the well-established orbital-based coupled cluster techniques employing correlation consistent atomic basis sets (aug-cc-pVXZ, X = T, Q, 5) and extrapolated to the complete basis set (CBS) limit. This work is performed on the benchmark rare gas-hydrogen halide interaction (HCl-He) system. These PESs are then incorporated into quantum close-coupling scattering dynamical calculations in order to check the impact of the accuracy of the PES on the scattering calculations. For this system, we deduced inelastic collisional data including (de-)excitation collisional and pressure broadening cross sections. Our work shows that the CCSD(T)-F12/aug-cc-pVTZ PES describes correctly the repulsive wall, the van der Waals minimum and long range internuclear distances whereas cc-pVXZ-F12 (X = D,T) basis sets are not diffuse enough for that purposes. Interestingly, the collision cross sections deduced from the CCSD(T)-F12/aug-cc-pVTZ PES are in excellent agreement with those obtained with CCSD(T)/CBS methodology. The position of the resonances and the general shape of these cross sections almost coincide. Since the cost of the electronic structure computations is reduced by several orders of magnitude when using CCSD(T)-F12/aug-cc-pVTZ compared to CCSD(T)/CBS methodology, this approach can be recommended as an alternative for generation of PESs of molecular clusters and for the interpretation of accurate scattering experiments as well as for a wide production of collisional data to be included in astrophysical and atmospherical models. PMID:23443908
The Impact of Natural Hydrologic Variability on the Accuracy of Remote Sensing Pond Surface Area Change Detection Studies Within the Canadian Subarctic
NASA Astrophysics Data System (ADS)
Parrott, J. A.; Macrae, M. L.; Duguay, C. R.
Within the sub-arctic environment, shallow ponds occupy 15-50% of the landscape and strongly contribute to regional hydrological and energy budgets. Given the unique hydrological environment in which they reside, ponds may be good indicators of regional environmental or climatic change. Therefore, accurately delineating and detecting surface area changes within these shallow water features is crucial when understanding the regional impacts of shifting climatic conditions. Recent remote sensing studies have revealed disparate results related to the long-term sustainability of sub-arctic shallow water features. However, many of these studies have not considered the impact of naturally induced hydrologic variability on the accuracy of change detection results. The overall objective of this study was to determine the impact of various environmentally driven hydrologic fluctuations on the ability for remotely sensed images to accurately capture pond surface area and detect change within the sub-arctic. Specifically, this study aimed to determine the influence of (a) inter-seasonal water balance fluctuations (b) antecedent precipitation prior to image acquisition and (c) anomalous annual climate (drought) on the quality of remote sensing studies focused on detecting long-term pond surface area change within the Hudson Bay Lowlands, near Churchill. The objectives were addressed using a combination of methods including climate data, field research, simple water balance modeling and remote sensing imagery. Specifically, a subset of 37 ponds, ranging in size from 918m2 to 34,624m2, were digitized and compared in order to detect surface area change linked to inter-seasonal hydrologic variability (two 1956 air photos), varying antecedent rainfall prior to acquisition dates (2000 and 2001 Landsat 7 images) and normal verses drought conditions (2000 Landsat 7 and 2006 SPOT images). Results from the imagery analyses were linked to climate data and a simple water balance model
Investigation on Multi-Physics Simulation-Based Virtual Machining System for Vibratory Finishing of Integrally Bladed Rotors (IBRS)
NASA Astrophysics Data System (ADS)
Achiamah-Ampomah, N.; Cheng, Kai
An investigation was carried out to improve the slow surface finishing times of integrally bladed rotors (IBRs) in the aerospace industry. Traditionally they are finished by hand, or more currently by abrasive flow machining. The use of a vibratory finishing technique to improve process times has been suggested; however as a largely empirical process, very few studies have been done to improve and optimize the cycle times, showing that critical and ongoing research is still needed in this area. An extensive review of the literature was carried out, and the findings used to identify the key parameters and model equations which govern the vibratory process. Recommendations were made towards a multi-physics-based simulation model, as well as projections made for the future of vibratory finishing and optimization of surface finishes and cycle times.
Accuracy Assessment of Aqua-MODIS Aerosol Optical Depth Over Coastal Regions: Importance of Quality Flag and Sea Surface Wind Speed
NASA Technical Reports Server (NTRS)
Anderson, J. C.; Wang, J.; Zeng, J.; Petrenko, M.; Leptoukh, G. G.; Ichoku, C.
Coastal regions around the globe are a major source for anthropogenic aerosols in the atmosphere, but the underlying surface characteristics are not favorable for the Moderate Resolution Imaging Spectroradiometer (MODIS) algorithms designed for retrieval of aerosols over dark land or open-ocean surfaces. Using data collected from 62 coastal stations worldwide from the Aerosol Robotic Network (AERONET) from approximately 2002-2010, accuracy assessments are made for coastal aerosol optical depth (AOD) retrieved from MODIS aboard Aqua satellite. It is found that coastal AODs (at 550 nm) characterized respectively by the MODIS Dark Land (hereafter Land) surface algorithm, the Open-Ocean (hereafter Ocean) algorithm, and AERONET all exhibit a log-normal distribution. After filtering by quality flags, the MODIS AODs respectively retrieved from the Land and Ocean algorithms are highly correlated with AERONET (with R(sup 2) is approximately equal to 0.8), but only the Land algorithm AODs fall within the expected error envelope greater than 66% of the time. Furthermore, the MODIS AODs from the Land algorithm, Ocean algorithm, and combined Land and Ocean product show statistically significant discrepancies from their respective counterparts from AERONET in terms of mean, probability density function, and cumulative density function, which suggest a need for future improvement in retrieval algorithms. Without filtering with quality flag, the MODIS Land and Ocean AOD dataset can be degraded by 30-50% in terms of mean bias. Overall, the MODIS Ocean algorithm overestimates the AERONET coastal AOD by 0.021 for AOD less than 0.25 and underestimates it by 0.029 for AOD greater than 0.25. This dichotomy is shown to be related to the ocean surface wind speed and cloud contamination effects on the satellite aerosol retrieval. The Modern Era Retrospective-Analysis for Research and Applications (MERRA) reveals that wind speeds over the global coastal region 25 (with a mean and median
Toward Chemical Accuracy in the Description of Ion-Water Interactions through Many-Body Representations. I. Halide-Water Dimer Potential Energy Surfaces.
Bajaj, Pushp; Götz, Andreas W; Paesani, Francesco
Despite recent progress, a unified understanding of how ions affect the structure and dynamics of water across different phases remains elusive. Here, we report the development of full-dimensional many-body potential energy functions, called MB-nrg (Many-Body-energy), for molecular simulations of halide ion-water systems from the gas phase to the condensed phase. The MB-nrg potentials are derived entirely from "first-principles" calculations carried out at the F12 explicitly correlated coupled-cluster level including single, double, and perturbative triple excitations, CCSD(T)-F12, in the complete basis set limit. Building upon the functional form of the MB-pol water potential, the MB-nrg potentials are expressed through the many-body expansion of the total energy in terms of explicit contributions representing one-body, two-body, and three-body interactions, with all higher-order contributions being described by classical induction. The specific focus of this study is on the MB-nrg two-body terms representing the full-dimensional potential energy surfaces (PESs) of the corresponding H2O-X(-) dimers, with X(-)= F(-), Cl(-), Br(-), and I(-). The accuracy of the MB-nrg PESs is systematically assessed through extensive comparisons with results obtained using both ab initio models and polarizable force fields for energies, structures, and harmonic frequencies of the H2O-X(-) dimers. PMID:27145081
Improvements in Sand Mold/Core Technology: Effects on Casting Finish
Prof. John J. Lannutti; Prof. Carroll E. Mobley
In this study, the development and impact of density gradients on metal castings were investigated using sand molds/cores from both industry and from in-house production. In spite of the size of the castings market, almost no quantitative information about density variation within the molds/cores themselves is available. In particular, a predictive understanding of how structure and binder content/chemistry/mixing contribute to the final surface finish of these products does not exist. In this program we attempted to bridge this gap by working directly with domestic companies in examining the issues of surface finish and thermal reclamation costs resulting from the use of sand molds/cores. We show that these can be substantially reduced by the development of an in-depth understanding of density variations that correlate to surface finish. Our experimental tools and our experience with them made us uniquely qualified to achieve technical progress.
Durable hydrophobic sol-gel finishing for textiles
NASA Astrophysics Data System (ADS)
Vihodceva, S.; Kukle, S.; Bitenieks, J.
The surface of cotton textile was modified to create a water-repellent finishing by depositing a modifying coatings using the sol-gel technique. Treated textiles evaluated using scanning electron microscopy, X-Ray powder diffraction (XRD). The wettability of treated fabrics was characterized by water contact angle and drop test. The results showed that the cotton textile treated with 7.5 wt.% zinc acetate dihydrate sol showed excellent hydrophobic properties, water contact angle could reach 145°C without decreasing after 50 hydrothermal treatment cycles.
Starch as a renewable finish to improve the pesticide-protective properties of conventional workclothes.
Obendorf, S K; Kasunick, R S; Ravichandran, V; Borsa, J; Coffman, C W
Because many pesticide handlers persist in wearing and reusing conventional workclothes, a renewable functional finish that enhances the pesticide-protective qualities of fabrics would be useful. This study investigated the ability of starch to act as a pesticide trap, preventing transfer and increasing removal by laundering, and the effect of carboxymethyl cellulose on release of pesticide in laundry. The retention and distribution of methyl parathion (MeP) on 65% polyester/35% cotton fabric was studied with four finishes: starch and carboxymethyl cellulose (CMC) as nondurable finishes; durable press resin (DP) and durable press/carboxymethyl cellulose (DP/CMC) as durable finishes. Starching with an add-on of 8% (w/w) effectively reduced the area of contamination and enhanced the removal of methyl parathion from polyester/cotton fabrics. Residual pesticide values for CMC, DP, and DP/CMC finishes were similar to that of the unfinished fabric. While distribution profiles of methyl parathion throughout the yarn and fiber structures were similar for all the finishes, lower concentrations of pesticide were observed on the cotton fibers from the starched fabric. Starch reduced the pesticide transferring by rubbing from both 100% cotton and 65% polyester/cotton fabrics. These studies support the intriguing theory that starch can act as a pesticide trap on the fabric surface to decrease pesticide transfer and to enhance pesticide removal. Extensive penetration studies, field studies, and additional investigation of fiber, yarn, and fabric parameters are needed to further quantify the effects of starch. PMID:1898107
Rheological properties of magnetorheological fluid and its finishing application on large aperture BK7 glass
NASA Astrophysics Data System (ADS)
Wang, C.; Wei, Q. L.; Huang, W.; Luo, Q.; He, J. G.; Tang, G. P.
The CeO2 nanoparticles with modified surface and mean sizes distribution during 107.0 nm - 127.7 nm are used as abrasive in magnetorheological finishing (MRF) fluid. The slow rotation dispersion without shearing thinning is better than fast emulsification dispersion. Steady D-shaped finishing spots and high quality precise processing surface with PV=0.1λ, GRMS=0.002λ/cm, Rq=0.83 nm are obtained on a 435 mm x 435 mm BK7 glass under self-developed MRF apparatus.
Quality evaluation of spaceborne SiC mirrors (I): analytical examination of the effects on mirror accuracy by variation in the thermal expansion property of the mirror surface.
Kotani, Masaki; Imai, Tadashi; Katayama, Haruyoshi; Yui, Yukari; Tange, Yoshio; Kaneda, Hidehiro; Nakagawa, Takao; Enya, Keigo
The Japan Aerospace Exploration Agency has studied a large-scale lightweight mirror constructed of reaction-bonded silicon carbide-based material as a key technology in future astronomical and earth observation missions. The authors selected silicon carbide as the promising candidate due to excellent characteristics of specific stiffness and thermal stability. One of the most important technical issues for large-scale ceramic components is the uniformity of the material's property, depending on part and processing. It might influence mirror accuracy due to uneven thermal deformation. The authors conducted systematic case studies for the conditions of CTE by finite element analysis to know the typical influence of material property nonuniformity on mirror accuracy and consequently derived a comprehensive empirical equation for the series of CTE's main factors. In addition, the authors computationally reproduced the mirror accuracy profile of a small prototype mirror shown in cryogenic testing and hereby verified wide-range practical computational evaluation technology of mirror accuracy. PMID:23852191
The paper presents results from two new studies at swine finishing facilities. (NOTE: Concentrated anaimal feeding operations (CAFOs) are being examined in several regions of the U.S. as major sources of ammonia and particulate matter precursors. EPA's National Risk Management Re...
Code of Federal Regulations, 2014 CFR
... 7 Agriculture 2 2014-01-01 2014-01-01 false Finish. 29.3022 Section 29.3022 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE COMMODITY STANDARDS AND STANDARD CONTAINER REGULATIONS TOBACCO INSPECTION Standards Official Standard...
Pneumonia outbreaks in calves and finishers.
Pneumonia in calves and finishers. Ovarian tumour in a calf . Abortion associated with bovine herpesvirus 1 in a suckler herd. Parasitic gastroenteritis causing illthrift and death in sheep. Outbreaks of acute fasciolosis in sheep. These are among matters discussed in the disease surveillance report for December 2015 from SAC Consulting: Veterinary Services (SAC C VS). PMID:26993450
Why Do Photo Finish Images Look Weird?
ERIC Educational Resources Information Center
Gregorcic, Bor; Planinsic, Gorazd
This paper deals with effects that appear on photographs of rotating objects when taken by a photo finish camera, a rolling shutter camera or a computer scanner. These effects are very similar to Roget's palisade illusion. A simple quantitative analysis of the images is also provided. The effects are explored using a computer scanner in a way that…
Evaluation of Some Finishing Properties of Oil Palm Particleboard for Furniture Application
NASA Astrophysics Data System (ADS)
Ratnasingam, J.; Nyugen, V.; Ioras, F.
The finishing properties of particleboard made from the Empty-Fruit Bunch (EFB) of oil palm (Elaeis guineensis Jacq.) were evaluated for its suitability for furniture applications, using different coating and overlay materials. The results found that the thick plastic-formica overlay provided the best surface finish, in terms of surface smoothness, adhesion strength and impact resistance. Although the polyurethane lacquer provided an acceptable finish, its quality and performance is not comparable to that of the thick plastic overlay. Despite the fact that the use of such overlay material may render the material not aesthetically appealing and limit it to concealed applications or where the thick overlay material is tolerated, its cost competitiveness and environmental friendliness may be able to position the oil palm particleboard as a substitute for the conventional wood-based particleboard in the furniture manufacturing industry.
Finishing procedures in orthodontic-surgical cases.
Brunel, Jean-Michel
To ensure optimal results, we must do our utmost to achieve targets based on order, symmetry and precision, our ultimate aim being to strive towards the desired harmony, planned contrast and exact proportions. Orthodontic-surgical treatments require specific finishing procedures, which most often call for multidisciplinary, or even transdisciplinary, collaboration. Finishing will involve the dental arches just as much as the orofacial environment. Above all, treatment of this kind demands a highly targeted approach in combination with well-defined and perfectly executed techniques. To finish a case satisfactorily, reasonable targets should be aimed for to ensure they are achieved. One must be ambitious and yet wise. A tight alliance of surgeon and orthodontist will nurture convincing and achievable projects and good, lifelong outcomes. Following the consolidation phase, roughly 4 to 6 weeks post-surgery, we can initiate the final orthodontic treatment, which, in effect, constitutes a mini-treatment in its own right. "Details make perfection, but perfection is not a detail" (Leonardo Da Vinci). "A lucid mind is the ante-chamber of intelligence" (Léo Ferré). In the order of life, every form of unity is always unique, and if each of us is unique, it is because everyone else is too. Ambition, wisdom, lucidity and efficiency will guarantee a successful result, the successful result. We must not be mere observers of our treatments, but the architect, project manager and site foreman at one and the same time. One could talk ad infinitum about finishing orthodontic-surgical cases because everything else leads up to the case-finishing and even the fullest description could never be exhaustive. PMID:26316452
Flame retardant finishing of cotton fabric based on synergistic compounds containing boron and nitrogen.
Xie, Kongliang; Gao, Aiqin; Zhang, Yongsheng
Boric acid and compound containing nitrogen, 2,4,6-tri[(2-hydroxy-3-trimethyl-ammonium)propyl]-1,3,5-triazine chloride (Tri-HTAC) were used to finish cotton fabric. The flame retardant properties of the finished cotton fabrics and the synergetic effects of boron and nitrogen elements were investigated and evaluated by limited oxygen index (LOI) method. The mechanism of cross-linking reaction among cotton fiber, Tri-HTAC, and boric acid was discussed by FTIR and element analysis. The thermal stability and surface morphology of the finished cotton fabrics were investigated by thermogravimetric analysis (TGA) and scanning electron microscope (SEM), respectively. The finishing system of the mixture containing boron and nitrogen showed excellent synergistic flame retardancy for cotton fabric. The cotton fabric finished with mixture system had excellent flame retardancy. The LOI value of the treated cotton fabric increased over 27.5. Tri-HTAC could form covalent bonds with cellulose fiber and boric acid. The flame retardant cotton fabric showed a slight decrease in tensile strength and whiteness. The surface morphology of flame retardant cotton fiber was smooth. PMID:23987402
Validation of accuracy and repeatability of UltraSurf metrology on common optical shapes
NASA Astrophysics Data System (ADS)
DeFisher, Scott; Matthews, Greg; Fess, Edward
Advancements in optical manufacturing technology allow optical designers to implement steep aspheric or high departure surfaces into their systems. Accurate metrology during the grinding and polishing stages of asphere manufacturing will reduce time and cost. Measuring these surfaces with common interferometers or profilometers can be difficult due to large surface slopes or unpolished surface texture. OptiPro has developed UltraSurf to qualify the form, figure, and thickness of steep aspheric and freeform optics. UltraSurf is a computer controlled, non-contact coordinate measuring machine. It incorporates five air-bearing axes, linear motors, high-resolution feedback, and a non-contact probe. The measuring probe is scanned over the optical surface while maintaining perpendicularity and a constant focal offset. There are multiple probe technologies available on UltraSurf, and each probe has strengths and weaknesses relative to the material properties, surface finish, and figure error of an optical component. Validation of the system accuracy, repeatability, and methodology must be performed to trust the measurement data. Form and figure maps of a flat, a sphere, and an asphere using UltraSurf will be presented with comparisons to interferometry. In addition, accuracy, repeatability, and machine qualification will be discussed.
Improved Microbe Assembly and Finishing Using 454 8kb Libraries
Buhay, Christian
Christian Buhay from Baylor College of Medicine's Human Genome Sequencing Center discusses microbial genome finishing strategies on June 3, 2010 at the "Sequencing, Finishing, Analysis in the Future" meeting in Santa Fe, NM
27 CFR 19.601 - Finished products records.
Code of Federal Regulations, 2011 CFR
... for redistillation; (7) Withdrawn for research, development or testing (including government samples... finished product; and (11) Disposed of as samples of the finished product. (26 U.S.C. 5207)...
Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey
FINISHED CASTINGS ARE ONLY GROUND BEFORE THEY ARE SHIPPED TO CUSTOMERS WHO COMPLETE THE FINISHING IN THEIR OWN MACHINE SHOPS. - Southern Ductile Casting Company, Grinding & Shipping, 2217 Carolina Avenue, Bessemer, Jefferson County, AL
This guide provides an overview of the major metal finishing processes and operations that generate waste and presents options for minimizing it through source reduction and recycling. etal finishing processes generate various waste streams, including contaminated plating baths, ...
27 CFR 19.601 - Finished products records.
Code of Federal Regulations, 2014 CFR
... and a daily summary record of the kind and quantity of finished products bottled or packaged within... transaction records and a daily summary record of the quantity of finished products bottled or packaged...
Realtime and High Accuracy VLBI in Chinese Lunar Exploration Project
NASA Astrophysics Data System (ADS)
Weimin, Zheng
The Chinese VLBI (Very Long Baseline Interferometry) Network - CVN consists of five radio telescopes and one data processing center. CVN is a powerful tracking and navigation tool in the Chinese lunar exploration projects. To meet the quick response of the CE lunar probes navigation requirements, station observation data must be sent to the VLBI center and processed in the real time mode. CVN has demonstrated its ability in the CE -1 and CE-2 missions. In December 2013, the CE-3 lander was successfully sent to the lunar surface and the Yutu rover was released. The new VLBI center and Tianma antenna came into use. During the mission, the lander carried the special Differential Oneway Range (DOR) beacon instead of the normal continuous spectrum VLBI signals. To get the high-precision result, CVN used the delta-DOR technique to track the lander with very extreme accuracy. VLBI delay residuals after orbit determination was nearly 0.5ns. The accuracy of landing position is better than 100 meters. The e-VLBI technique made the observable turnover time as short as 20~40 seconds. The same beam VLBI was used to determine the relative position between the lander and rover with meter accuracy. In the subsequent lunar missions, the new deep stations will join CVN and extend the baseline length. After the soft landing and sampling, the lander will be launched from the lunar surface and finish rendezvous and docking with the orbiter. The VLBI synthesis mapping method and the same beam VLBI can get the accurate lander location and support the rendezvous and docking procedure.
Wetting studies of lead-free solders on lead-free PWB finishes
NASA Astrophysics Data System (ADS)
Sattiraju, Seshagirirao Venkata
There is a universal focus for producing environmentally friendly products in many different areas of science and engineering. Pb in electronic solder has become the target recently. The shift towards Pb-free manufacturing is a complicated issue. For a successful transition to Pb-free manufacturing in electronics assembly, it is critical to understand the behavior of Pb-free solders (in bulk and paste form) and their interaction with the Pb-free printed wiring board (PWB) finishes before their implementation in high volume electronics manufacturing can be realized. In this research work, studies were performed to characterize the wetting process of some Pb-free solders and Pb-free PWB finishes. Results obtained from solder paste spread tests and wetting balance experiments with several Pb-free solder alloys and Pb-free PWB finishes are presented and conclusions are drawn on the solderability of the alloys and finishes. The solder alloys studied were Sn3.4Ag4.8Bi, Sn4.0Ag0.5 Cu, Sn3.5Ag and Sn0.7Cu. Eutectic Sn37Pb was used as a reference. The PWB surface finishes were immersion Sn, electroless Ni/immersion Au, immersion Ag and organic solderability preservative (OSP). Effects of multiple reflow cycles on solderability of the test coupons were also studied. Statistical analyses were performed on the data obtained from the wetting balance and spread tests. Wetting balance experiments were conducted in air while the spread tests were performed in air and nitrogen to understand the effect of reflow atmosphere on the spreading. Surface analyses techniques such as Auger Electron Spectroscopy (AES) and X-ray Photoelectron Spectroscopy (XPS) were applied to understand and analyze the surfaces. Conclusions were drawn based on the data obtained from the wetting balance and spread experiments and results from the surface and thermodynamic analyses were applied to augment the experimental results. Sequential Electrochemical Reduction Analysis (SERA) was also performed on the
Nearly Finished Genomes Produced Using Gel Microdroplet Culturing (Seventh Annual Sequencing, Finishing, Analysis in the Future (SFAF) Meeting 2012)
Fitzsimmons, Michael [LANL
Michael Fitzsimmons from Los Alamos National Laboratory gives a talk titled "Nearly Finished Genomes Produced Using Gel Microdroplet Culturing" at the 7th Annual Sequencing, Finishing, Analysis in the Future (SFAF) Meeting held in June, 2012 in Santa Fe, NM.
Removal rate model for magnetorheological finishing of glass.
Degroote, Jessica E; Marino, Anne E; Wilson, John P; Bishop, Amy L; Lambropoulos, John C; Jacobs, Stephen D
Magnetorheological finishing (MRF) is a deterministic subaperture polishing process. The process uses a magnetorheological (MR) fluid that consists of micrometer-sized, spherical, magnetic carbonyl iron (CI) particles, nonmagnetic polishing abrasives, water, and stabilizers. Material removal occurs when the CI and nonmagnetic polishing abrasives shear material off the surface being polished. We introduce a new MRF material removal rate model for glass. This model contains terms for the near surface mechanical properties of glass, drag force, polishing abrasive size and concentration, chemical durability of the glass, MR fluid pH, and the glass composition. We introduce quantitative chemical predictors for the first time, to the best of our knowledge, into an MRF removal rate model. We validate individual terms in our model separately and then combine all of the terms to show the whole MRF material removal model compared with experimental data. All of our experimental data were obtained using nanodiamond MR fluids and a set of six optical glasses. PMID:17994145
Removal Rate Model for Magnetorheological Finishing of Glass
DeGroote, J.E.; Marino, A.E.; WIlson, J.P.; Bishop, A.L.; Lambropoulos, J.C.; Jacobs, S.D.
Magnetorheological finishing (MRF) is a deterministic subaperture polishing process. The process uses a magntorheological (MR) fluid that consists of micrometer-sized, spherical, magnetic carbonyl iron (CI) particles, nonmagnetic polishing abrasives, water, and stabilizers. Material removal occurs when the CI and nonmagnetic polishing abrasives shear material off the surface being polished. We introduce a new MRF material removal rate model for glass. This model contains terms for the near surface mechanical properties of glass, drag force, polishing abrasive size and concentration, chemical durability of the glass, MR fluid pH, and the glass composition. We introduce quantitative chemical predictors for the first time, to the best of our knowledge, into an MRF removal rate model. We validate individual terms in our model separately and then combine all of the terms to show the whole MRF material removal model compared with experimental data. All of our experimental data were obtained using nanodiamond MR fluids and a set of six optical glasses.
Sequence finishing and mapping of Drosophila melanogasterheterochromatin
Hoskins, Roger A.; Carlson, Joseph W.; Kennedy, Cameron; Acevedo,David; Evans-Holm, Martha; Frise, Erwin; Wan, Kenneth H.; Park, Soo; Mendez-Lago, Maria; Rossi, Fabrizio; Villasante, Alfredo; Dimitri,Patrizio; Karpen, Gary H.; Celniker, Susan E.
Genome sequences for most metazoans are incomplete due tothe presence of repeated DNA in the pericentromeric heterochromatin. Theheterochromatic regions of D. melanogaster contain 20 Mb of sequenceamenable to mapping, sequence assembly and finishing. Here we describethe generation of 15 Mb of finished or improved heterochromatic sequenceusing available clone resources and assembly and mapping methods. We alsoconstructed a BAC-based physical map that spans approximately 13 Mb ofthe pericentromeric heterochromatin, and a cytogenetic map that positionsapproximately 11 Mb of BAC contigs and sequence scaffolds in specificchromosomal locations. The integrated sequence assembly and maps greatlyimprove our understanding of the structure and composition of this poorlyunderstood fraction of a metazoan genome and provide a framework forfunctional analyses.
Agile robotic edge finishing system research
Powell, M.A.
This paper describes a new project undertaken by Sandia National Laboratories to develop an agile, automated, high-precision edge finishing system. The project has a two-year duration and was initiated in October, 1994. This project involves re-designing and adding additional capabilities to an existing finishing workcell at Sandia; and developing intelligent methods for automating process definition and for controlling finishing processes. The resulting system will serve as a prototype for systems that will be deployed into highly flexible automated production lines. The production systems will be used to produce a wide variety of products with limited production quantities and quick turnaround requirements. The prototype system is designed to allow programming, process definition, fixture re-configuration, and process verification to be performed off-line for new products. CAD/CAM (Computer Aided Design/Computer Aided Manufacturing) models of the part will be used to assist with the automated process development and process control tasks. To achieve Sandia`s performance goals, the system will be employ advanced path planning, burr prediction expert systems, automated process definition, statistical process models in a process database, and a two-level control scheme using hybrid position-force control and fuzzy logic control. In this paper, we discuss the progress and the planned system development under this project.
Research on error control and compensation in magnetorheological finishing.
Dai, Yifan; Hu, Hao; Peng, Xiaoqiang; Wang, Jianmin; Shi, Feng
Although magnetorheological finishing (MRF) is a deterministic finishing technology, the machining results always fall short of simulation precision in the actual process, and it cannot meet the precision requirements just through a single treatment but after several iterations. We investigate the reasons for this problem through simulations and experiments. Through controlling and compensating the chief errors in the manufacturing procedure, such as removal function calculation error, positioning error of the removal function, and dynamic performance limitation of the CNC machine, the residual error convergence ratio (ratio of figure error before and after processing) in a single process is obviously increased, and higher figure precision is achieved. Finally, an improved technical process is presented based on these researches, and the verification experiment is accomplished on the experimental device we developed. The part is a circular plane mirror of fused silica material, and the surface figure error is improved from the initial λ/5 [peak-to-valley (PV) λ=632.8 nm], λ/30 [root-mean-square (rms)] to the final λ/40 (PV), λ/330 (rms) just through one iteration in 4.4 min. Results show that a higher convergence ratio and processing precision can be obtained by adopting error control and compensation techniques in MRF. PMID:21743536
Antimicrobial finish of textiles by chitosan UV-curing.
Ferrero, Franco; Periolatto, Monica
The purpose of this research work was to develop a textile finish based on the radical UV-curing of chitosan on textiles to confer antimicrobial properties. Chitosan is a biopolymer with unique properties such as biodegradability, non-toxicity, antimicrobial activity. In this work cotton or silk fabrics and synthetic filter fabrics were impregnated with an acid solution of chitosan added of the photoinitiator in the proper amount and cured at room temperature by exposure to UV lamp. Process conditions such as percentage add-on, dilution, chitosan-fabric contact time, irradiation time and power, were optimized. The antimicrobial activity of finished fabrics was tested according to ASTM E 2149-01 standard test performed with Escherichia Coli ATCC 8739. Moreover dyeing test with Turquoise Telon dye were carried out to evaluate the treatment homogeneity while the amino group content was determined by ninhydrin assay. Moreover on cotton and silk fabrics the treatment fastness to domestic laundering was tested, according to UNI EN ISO105-C01. Obtained results showed a strong antimicrobial activity conferred by the treatment, homogeneous on fabric surface. It is evident already at low add-on, without affecting the hand properties of natural fabrics and the filtration characteristics of the synthetic filter fabrics. Finally, washing fastness was better for samples prepared with a better penetration of chitosan inside the fibers. PMID:22905533
Slow tool servo diamond turning of optical freeform surface for astigmatic contact lens
NASA Astrophysics Data System (ADS)
Chen, Chun-Chieh; Cheng, Yuan-Chieh; Hsu, Wei-Yao; Chou, Hsiao-Yu; Wang, Pei-Jen; Tsai, Din Ping
Three ultra-precision machining processes namely fast tool servo, slow tool servo and diamond milling, are frequently used to produce optical freeform surface. Slow tool servo machining has the advantages of no extra attachment and fast setting-up, however the three dimensional tool shape compensation and tool-path generation must be conducted carefully for getting high form accuracy and fine surface finish. This research aimed to develop a model of three dimensional tool shape compensation for generating 3D tool path in slow tool servo diamond turning of asymmetrically toric surface for astigmatic contact lens. The form accuracy of freeform surface was measured by ultra-high accuracy 3D profilometer (UA3P) with user define function. After correction, the form error is less than 0.5μm both in X- and Y-direction and the surface roughness is less than 5nm.
Percent recoveries of anthropogenic organic compounds with and without the addition of ascorbic acid to preserve finished-water samples containing free chlorine, 2004-10
Valder, Joshua F.; Delzer, Gregory C.; Bender, David A.; Price, Curtis V.
This report presents finished-water matrix-spike recoveries of 270 anthropogenic organic compounds with and without the addition of ascorbic acid to preserve water samples containing free chlorine. Percent recoveries were calculated using analytical results from a study conducted during 2004-10 for the National Water-Quality Assessment (NAWQA) Program of the U.S. Geological Survey (USGS). The study was intended to characterize the effect of quenching on finished-water matrix-spike recoveries and to better understand the potential oxidation and transformation of 270 anthropogenic organic compounds. The anthropogenic organic compounds studied include those on analytical schedules 1433, 2003, 2033, 2060, 2020, and 4024 of the USGS National Water Quality Laboratory. Three types of samples were collected from 34 NAWQA locations across the Nation: (1) quenched finished-water samples (not spiked), (2) quenched finished-water matrix-spike samples, and (3) nonquenched finished-water matrix-spike samples. Percent recoveries of anthropogenic organic compounds in quenched and nonquenched finished-water matrix-spike samples are presented. Comparisons of percent recoveries between quenched and nonquenched spiked samples can be used to show how quenching affects finished-water samples. A maximum of 18 surface-water and 34 groundwater quenched finished-water matrix-spike samples paired with nonquenched finished-water matrix-spike samples were analyzed. Percent recoveries for the study are presented in two ways: (1) finished-water matrix-spike samples supplied by surface-water or groundwater, and (2) by use (or source) group category for surface-water and groundwater supplies. Graphical representations of percent recoveries for the quenched and nonquenched finished-water matrix-spike samples also are presented.
Specifying colour and maintaining colour accuracy for 3D printing
NASA Astrophysics Data System (ADS)
Parraman, Carinna; Walters, Peter; Reid, Brendan; Huson, David
Advances in rapid prototyping technologies have led to the emergence of three-dimensional printers which can fabricate physical artefacts, including the application of surface colours. In light of these developments, this paper asserts that the need to print colour accurately is just as important for designers using three-dimensional colour printing as it is for two-dimensional inkjet printing. Parallels can be made with two-dimensional digital Inkjet printing and 2D common problems include: on screen previsualisation, colour management methods, colour gamut and maintaining colour accuracy. However, for three dimensional colour printed objects, there are more variables that will affect the finished colour. These are: the powder and process inks, unevenness of the surface, wax post-processing and other infiltration media and procedures. Furthermore, in some 3D printers, the K channel is replaced by the binder and so the printer is only using the cyan, magenta and yellow channels. The paper will suggest methods for improving pre-visualisation and accurate pre-viewing of the colours through the manufacture of three-dimensional colour charts as a reference guide for designers so that they can make accurate coloured artefacts. A series of case studies will be demonstrated.
A Comparative Evaluation of Dimensional Accuracy and Surface Detail Reproduction of Four Hydrophilic Vinyl Polysiloxane Impression Materials Tested Under Dry, Moist, and Wet Conditions-An In Vitro Study.
Nagrath, Rahul; Lahori, Manesh; Agrawal, Manjari
Vinyl polysiloxane (VPS) impression materials have application in a wide variety of situations in both fixed and removable prosthodontics. A major limitation of VPS impression materials is their hydrophobicity. There are two aspects of this problem, the wettability of the polymerized impression by dental gypsum materials and the ability of the unpolymerized material to wet intraoral tissues. To address this problem, manufacturers have added surfactants and labelled these new products as "hydrophilic vinyl polysiloxane." The purpose of this study was to evaluate and compare dimensional accuracy and surface detail reproduction of four hydrophilic VPS impression materials, when used under dry, moist, and wet conditions. A total of 180 samples were made of stainless steel die similar to as described in ADA sp. no. 19. The die was scored with three horizontal and two vertical lines. Impressions were made under dry, moist and wet conditions. Dimensional accuracy was measured by comparing the length of the middle horizontal line in each impression to the same line on the metal die, by using Universal Length Measuring machine. A 2-way ANOVA was performed on the percentage change data for measured lengths of the 4 impression materials under the 3 conditions to evaluate dimensional accuracy. Surface detail was evaluated in two ways: (1) by use of criteria similar to ADA sp. no. 19 for detail reproduction, and (2) by use of a method that categorized the impressions as satisfactory or unsatisfactory based on their surface characteristics: presence of pits, voids, or roughness. Pearson X2 (α = 0.05) was used to compare surface detail reproduction results. Conditions (dry, moist, and wet) did not cause significant adverse effects on the dimensional accuracy of all the four material. With both surface detail analyses, dry, moist, and wet conditions had a significant effect on the detail reproduction of all the four materials (P < 0.05). The study concluded that the
A Methodology to Assess the Accuracy with which Remote Data Characterize a Specific Surface, as a Function of Full Width at Half Maximum (FWHM): Application to Three Italian Coastal Waters
Cavalli, Rosa Maria; Betti, Mattia; Campanelli, Alessandra; Di Cicco, Annalisa; Guglietta, Daniela; Penna, Pierluigi; Piermattei, Viviana
This methodology assesses the accuracy with which remote data characterizes a surface, as a function of Full Width at Half Maximum (FWHM). The purpose is to identify the best remote data that improves the characterization of a surface, evaluating the number of bands in the spectral range. The first step creates an accurate dataset of remote simulated data, using in situ hyperspectral reflectances. The second step evaluates the capability of remote simulated data to characterize this surface. The spectral similarity measurements, which are obtained using classifiers, provide this capability. The third step examines the precision of this capability. The assumption is that in situ hyperspectral reflectances are considered the "real" reflectances. They are resized with the same spectral range of the remote data. The spectral similarity measurements which are obtained from "real" resized reflectances, are considered "real" measurements. Therefore, the quantity and magnitude of "errors" (i.e., differences between spectral similarity measurements obtained from "real" resized reflectances and from remote data) provide the accuracy as a function of FWHM. This methodology was applied to evaluate the accuracy with which CHRIS-mode1, CHRIS-mode2, Landsat5-TM, MIVIS and PRISMA data characterize three coastal waters. Their mean values of uncertainty are 1.59%, 3.79%, 7.75%, 3.15% and 1.18%, respectively. PMID:24434875
Carcass quality and meat tenderness of Hawaii pasture-finished cattle and Hawaii-originated, mainland feedlot-finished cattle.
Kim, Yong Soo; Fukumoto, Glen Kazumi; Kim, Sunae
The objective of this study was to compare the carcass quality and meat tenderness of Hawaii cattle finished on subtropical pasture with those of mainland US feedlot-finished cattle that were shipped from Hawaii after weaning. Rib-eye steak samples were collected from 30 feedlot-finished cattle harvested at a slaughter house in Washington State, USA and from 13 subtropical pasture-finished cattle harvested at a local slaughter house in Hawaii, then shipped to meat science laboratory at the University of Hawaii, Manoa. Samples were aged for 2 weeks at 4°C and frozen for later proximate analysis and meat tenderness measurement. Feedlot-finished cattle had significantly heavier carcass weight (353 vs 290 kg) and thicker backfat (13.5 vs 6.6 mm), but no significant difference was observed in rib-eye area between the two groups. Marbling score (Small) and United States Department of Agriculture quality grade (Choice) of the pasture-finished beef were not significantly (P < 0.05) different from those of feedlot-finished beef. The shear force value of pasture-finished beef (5.18 kg) was not statistically different (P < 0.05) from that of feedlot-finished beef (4.40 kg). In conclusion, results of this study suggest that Hawaii cattle finished on subtropical pasture produced as tender beef as mainland feedlot-finished cattle with less intramuscular fat. PMID:22274716
Anthropogenic impervious surfaces have an important relationship with non-point source pollution (NPS) in urban watersheds. The amount of impervious surface area in a watershed is a key indicator of landscape change. As a single variable, it serves to intcgrate a number of concur...
The effects of stainless steel finish on Salmonella Typhimurium attachment, biofilm formation and sensitivity to chlorine.
Schlisselberg, Dov B; Yaron, Sima
Bacterial colonization and biofilm formation on stainless steel (SS) surfaces can be sources for cross contamination in food processing facilities, possessing a great threat to public health and food quality. Here the aim was to demonstrate the influence of surface finish of AISI 316 SS on colonization, biofilm formation and susceptibility of Salmonella Typhimurium to disinfection. Initial attachment of S. Typhimurium on surfaces of SS was four times lower, when surface was polished by Bright-Alum (BA) or Electropolishing (EP), as compared to Mechanical Sanded (MS) or the untreated surface (NT). The correlation between roughness and initial bacterial attachment couldn't account on its own to explain differences seen. Biofilms with similar thickness (15-18 μm) were developed on all surfaces 1-day post inoculation, whereas EP was the least covered surface (23%). Following 5-days, biofilm thickness was lowest on EP and MS (30 μm) and highest on NT (62 μm) surfaces. An analysis of surface composition suggested a link between surface chemistry and biofilm development, where the higher concentrations of metal ions in EP and MS surfaces correlated with limited biofilm formation. Interestingly, disinfection of biofilms with chlorine was up to 130 times more effective on the EP surface (0.005% surviving) than on the other surfaces. Overall these results suggest that surface finish should be considered carefully in a food processing plant. PMID:23628616
Summary Results of the Neptun Boil-Off Experiments to Investigate the Accuracy and Cooling Influence of LOFT Cladding-Surface Thermocouples (System 00)
E. L. Tolman S. N. Aksan
Nine boil-off experiments were conducted in the Swiss NEPTUN Facility primarily to obtain experimental data for assessing the perturbation effects of LOFT thermocouples during simulated small-break core uncovery conditions. The data will also be useful in assessing computer model capability to predict thermal hydraulic response data for this type of experiment. System parameters that were varied for these experiments included heater rod power, system pressure, and initial coolant subcooling. The experiments showed that the LOFT thermocouples do not cause a significant cooling influence in the rods to which they are attached. Furthermore, the accuracy of the LOFT thermocouples is within 20 K at the peak cladding temperature zone.
Analysis of thermal sources in a magnetorheological finishing (MRF) process
NASA Astrophysics Data System (ADS)
Geiss, Andreas; Schinhaerl, Markus; Pitschke, Elmar; Rascher, Rolf; Sperber, Peter
Magnetorheological finishing (MRF) is a computer controlled polishing (CCP) technique for high quality surfaces. The process uses a magnetorheological fluid which stiffens in a magnetic field and thus acts as the polishing tool. At the University of Applied Sciences Deggendorf thermal sources in a MRF polishing unit have been analysed using an infrared camera. The result of the research is a warming of the fluid in the fluid conditioner caused by the mixer motor. The existing cooling is therefore essential, in order to ensure a constant polishing tool characteristic during polishing runs. A new fluid conditioner, which was developed at the University of Applied Sciences Deggendorf, with the aim of an extended fluid lifetime may be used without cooling, because an increase of the fluid temperature in the conditioner could not been detected. Furthermore, a warming of the workpiece during the polishing process was not ascertainable.
Textural characterization of finished and polished composites over time of intraoral exposure.
Turssi, Cecilia Pedroso; Rodrigues, Antonio Luiz; Serra, Mônica Campos
This in situ study sought to evaluate the surface roughness evolution of resin composites finished and polished by different methods. A total of 108 rectangular-shaped specimens of a microfilled and a hybrid composite were cured against a Mylar matrix strip and left unpolished or instrumented with diamond burs, Al2O3-coated disks, Al2O3-impregnated UDMA disk, or with diamond burs followed by either one of the disks. After specimens had been profiled for the average surface roughness (Ra, microm), 18 volunteers wore a removable palatal appliance, which accommodated one specimen of each one of the 12 groups investigated. Surface roughness for up to 28 days of intraoral exposure was then measured at 1- or 7-day intervals. A split-plot ANOVA (alpha = 0.05) revealed a significant interaction between group and time. Tukey's test and regression analyses ascertained that initially finishing with burs only provided the roughest surface to both composites. Unpolished surfaces and those specimens polished with Al2O3-coated disks, regardless of previous use of diamond burs, attained smoother surface. The Al2O3-impregnated UDMA disk was capable of smoothening the surface of the hybrid material previously finished with diamond burs. The roughness achieved after finishing and polishing composites may be either smoothened or roughened after intraoral exposure. On the basis of the roughness range, it is advisable to use Al2O3-coated disks, regardless of whether diamond burs were previously used. Al2O3-impregnated UDMA disks (with or without previous application of diamond burs) may be also suitable for instrumenting hybrid restoratives. PMID:16206257
Accuracy assessment of land surface temperature retrievals from Landsat 7 ETM + in the Dry Valleys of Antarctica using iButton temperature loggers and weather station data.
Brabyn, Lars; Zawar-Reza, Peyman; Stichbury, Glen; Cary, Craig; Storey, Bryan; Laughlin, Daniel C; Katurji, Marwan
The McMurdo Dry Valleys of Antarctica are the largest snow/ice-free regions on this vast continent, comprising 1% of the land mass. Due to harsh environmental conditions, the valleys are bereft of any vegetation. Land surface temperature is a key determinate of microclimate and a driver for sensible and latent heat fluxes of the surface. The Dry Valleys have been the focus of ecological studies as they arguably provide the simplest trophic structure suitable for modelling. In this paper, we employ a validation method for land surface temperatures obtained from Landsat 7 ETM + imagery and compared with in situ land surface temperature data collected from four transects totalling 45 iButtons. A single meteorological station was used to obtain a better understanding of daily and seasonal cycles in land surface temperatures. Results show a good agreement between the iButton and the Landsat 7 ETM + product for clear sky cases. We conclude that Landsat 7 ETM + derived land surface temperatures can be used at broad spatial scales for ecological and meteorological research. PMID:24366817
Fluor Hanford is pleased to submit the Plutonium Finishing Plant (PFP) Stabilization and Packaging Project (SPP) for consideration by the Project Management Institute as Project of the Year for 2004. The SPP thermally stabilized and/or packaged nearly 18 metric tons (MT) of plutonium and plutonium-bearing materials left in PFP facilities from 40 years of nuclear weapons production and experimentation. The stabilization of the plutonium-bearing materials substantially reduced the radiological risk to the environment and security concerns regarding the potential for terrorists to acquire the non-stabilized plutonium products for nefarious purposes. The work was done In older facilities which were never designed for the long-term storage of plutonium, and required working with materials that were extremely radioactive, hazardous, pyrophoric, and In some cases completely unique. I n some Instances, one-of-a-kind processes and equipment were designed, installed, and started up. The SPP was completed ahead of schedule, substantially beating all Interim progress milestone dates set by the Defense Nuclear Facilities Safety Board (DNFSB) and in the Hanford Site's Federal Facility Agreement and Consent Order (Tri-Party Agreement or TPA), and finished $1-million under budget.
Finishing bacterial genome assemblies with Mix
Motivation Among challenges that hamper reaping the benefits of genome assembly are both unfinished assemblies and the ensuing experimental costs. First, numerous software solutions for genome de novo assembly are available, each having its advantages and drawbacks, without clear guidelines as to how to choose among them. Second, these solutions produce draft assemblies that often require a resource intensive finishing phase. Methods In this paper we address these two aspects by developing Mix , a tool that mixes two or more draft assemblies, without relying on a reference genome and having the goal to reduce contig fragmentation and thus speed-up genome finishing. The proposed algorithm builds an extension graph where vertices represent extremities of contigs and edges represent existing alignments between these extremities. These alignment edges are used for contig extension. The resulting output assembly corresponds to a set of paths in the extension graph that maximizes the cumulative contig length. Results We evaluate the performance of Mix on bacterial NGS data from the GAGE-B study and apply it to newly sequenced Mycoplasma genomes. Resulting final assemblies demonstrate a significant improvement in the overall assembly quality. In particular, Mix is consistent by providing better overall quality results even when the choice is guided solely by standard assembly statistics, as is the case for de novo projects. Availability Mix is implemented in Python and is available at https://github.com/cbib/MIX, novel data for our Mycoplasma study is available at http://services.cbib.u-bordeaux2.fr/mix/. PMID:24564706
On the accuracy of stratospheric aerosol extinction derived from in situ size distribution measurements and surface area density derived from remote SAGE II and HALOE extinction measurements
NASA Astrophysics Data System (ADS)
Kovilakam, Mahesh; Deshler, Terry
In situ stratospheric aerosol measurements, from University of Wyoming optical particle counters (OPCs), are compared with Stratospheric Aerosol Gas Experiment (SAGE) II (versions 6.2 and 7.0) and Halogen Occultation Experiment (HALOE) satellite measurements to investigate differences between SAGE II/HALOE-measured extinction and derived surface area and OPC-derived extinction and surface area. Coincident OPC and SAGE II measurements are compared for a volcanic (1991-1996) and nonvolcanic (1997-2005) period. OPC calculated extinctions agree with SAGE II measurements, within instrumental uncertainty, during the volcanic period, but have been a factor of 2 low during the nonvolcanic period. Three systematic errors associated with the OPC measurements, anisokineticity, inlet particle evaporation, and counting efficiency, were investigated. An overestimation of the OPC counting efficiency is found to be the major source of systematic error. With this correction OPC calculated extinction increases by 15-30% (30-50%) for the volcanic (nonvolcanic) measurements. These changes significantly improve the comparison with SAGE II and HALOE extinctions in the nonvolcanic cases but slightly degrade the agreement in the volcanic period. These corrections have impacts on OPC-derived surface area density, exacerbating the poor agreement between OPC and SAGE II (version 6.2) surface areas. This disparity is reconciled with SAGE II version 7.0 surface areas. For both the volcanic and nonvolcanic cases these changes in OPC counting efficiency and in the operational SAGE II surface area algorithm leave the derived surface areas from both platforms in significantly better agreement and within the ± 40% precision of the OPC moment calculations.
On the accuracy of stratospheric aerosol extinction derived from in situ size distribution measurements and surface area density derived from remote SAGE II and HALOE extinction measurements
Kovilakam, Mahesh; Deshler, Terry
In situ stratospheric aerosol measurements, from University of Wyoming optical particle counters (OPCs), are compared with Stratospheric Aerosol Gas Experiment (SAGE) II (versions 6.2 and 7.0) and Halogen Occultation Experiment (HALOE) satellite measurements to investigate differences between SAGE II/HALOE-measured extinction and derived surface area and OPC-derived extinction and surface area. Coincident OPC and SAGE II measurements are compared for a volcanic (1991-1996) and nonvolcanic (1997 2005) period. OPC calculated extinctions agree with SAGE II measurements, within instrumental uncertainty, during the volcanic period, but have been a factor of 2 low during the nonvolcanic period. Three systematic errors associated with themore » OPC measurements, anisokineticity, inlet particle evaporation, and counting efficiency, were investigated. An overestimation of the OPC counting efficiency is found to be the major source of systematic error. With this correction OPC calculated extinction increases by 15 30% (30 50%) for the volcanic (nonvolcanic) measurements. These changes significantly improve the comparison with SAGE II and HALOE extinctions in the nonvolcanic cases but slightly degrade the agreement in the volcanic period. These corrections have impacts on OPC-derived surface area density, exacerbating the poor agreement between OPC and SAGE II (version 6.2) surface areas. This disparity is reconciled with SAGE II version 7.0 surface areas. For both the volcanic and nonvolcanic cases these changes in OPC counting efficiency and in the operational SAGE II surface area algorithm leave the derived surface areas from both platforms in significantly better agreement and within the 40% precision of the OPC moment calculations.« less
On the accuracy of stratospheric aerosol extinction derived from in situ size distribution measurements and surface area density derived from remote SAGE II and HALOE extinction measurements
Kovilakam, Mahesh; Deshler, Terry
In situ stratospheric aerosol measurements, from University of Wyoming optical particle counters (OPCs), are compared with Stratospheric Aerosol Gas Experiment (SAGE) II (versions 6.2 and 7.0) and Halogen Occultation Experiment (HALOE) satellite measurements to investigate differences between SAGE II/HALOE-measured extinction and derived surface area and OPC-derived extinction and surface area. Coincident OPC and SAGE II measurements are compared for a volcanic (1991-1996) and nonvolcanic (1997 2005) period. OPC calculated extinctions agree with SAGE II measurements, within instrumental uncertainty, during the volcanic period, but have been a factor of 2 low during the nonvolcanic period. Three systematic errors associated with the OPC measurements, anisokineticity, inlet particle evaporation, and counting efficiency, were investigated. An overestimation of the OPC counting efficiency is found to be the major source of systematic error. With this correction OPC calculated extinction increases by 15 30% (30 50%) for the volcanic (nonvolcanic) measurements. These changes significantly improve the comparison with SAGE II and HALOE extinctions in the nonvolcanic cases but slightly degrade the agreement in the volcanic period. These corrections have impacts on OPC-derived surface area density, exacerbating the poor agreement between OPC and SAGE II (version 6.2) surface areas. This disparity is reconciled with SAGE II version 7.0 surface areas. For both the volcanic and nonvolcanic cases these changes in OPC counting efficiency and in the operational SAGE II surface area algorithm leave the derived surface areas from both platforms in significantly better agreement and within the 40% precision of the OPC moment calculations.
[Experimental analysis of finishing lines in ceramometal restorations].
Gascón, F; Gil, J A; Fons, A; Badal, R
The preparation is the first step of any tooth reconstruction. The biological integration of the protesis is depending on the marginal adaptation (finish line of the preparation), occlusal adaptation (occlusal reduction), longevity of the restoration (retention and luting) and esthetics. The effect the two finish line of the preparation is studied using experimental design. In porcelain-fused-to-metal the finish line of the preparation in chanfer is superior at the beveled shoulder, because proportioning better marginal adaptation. PMID:2076124
11. Exterior detail view of northeast corner, showing stucco finish ...
Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey
11. Exterior detail view of northeast corner, showing stucco finish and woodwork details - American Railway Express Company Freight Building, 1060 Northeast Division Street, Bend, Deschutes County, OR
Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey
6. FACTORY BUILDING, WITH FINISHED PRODUCT WAREHOUSE IN RIGHT BACKGROUND. VIEW TO NORTHWEST. - Commercial & Industrial Buildings, Maizewood Insulation Company Factory, 275 Salina Street, Dubuque, Dubuque County, IA
Hazardous waste reduction in the metal finishing industry
Not Available
This study identifies opportunities for waste reduction available to the metal finishing industry and develops a generic audit protocol that can be used by metal finishers to assess their own waste reduction opportunities. The study emphasizes technologies available to metal finishing plants of various sizes. Typically, these shops operate a variety of physical, chemical and electrochemical processes. Chemical processes include degreasing, cleaning, pickling, etching, coating, and electroless plating. Electrochemical processes include plating and anodizing. The study identifies three categories of waste reduction technologies that are available to metal finishers: source reduction, recycling and resource recovery, and alternative treatment.
Finishing The Euchromatic Sequence Of The Human Genome
Rubin, Edward M.; Lucas, Susan; Richardson, Paul; Rokhsar, Daniel; Pennacchio, Len
The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process.The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers {approx}99% of the euchromatic genome and is accurate to an error rate of {approx}1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number,birth and death. Notably, the human genome seems to encode only20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead.
Detection of Protozoa in Surface and Finished Waters
Humans are known to be the host to approximately 1500 infectious agents, out of which 66 are protozoa and 287 are helminths. Therefore, from a global perspective helminths and protozoan parasites account for approximately one fourth of the total infectious diseases of humans. A s...
Sintered silicon carbide mirror substrates surface finishing for embedded applications
NASA Astrophysics Data System (ADS)
Damião, A. J.; Valentim Ribeiro dos Santos, M.
Stiffness is the main reason to use SiC as a mirror substrate for aerospace applications. Also the SiC mechanical and thermal properties are superior to the optical material that is normally used for those applications. In this work, diamond tools and pastes were applied to obtain flat small diameter mirror substrates. The goals were to obtain flatness of λ/10 and Ra roughness of λ/100, for visible light.
Responsive Surface Finishing of Textiles using Smart Polymers
NASA Astrophysics Data System (ADS)
Ramaratnam, Karthik; Fan, Qinguo
Smart polymers that can change their properties according to the environment have significant potential in widespread applications. Poly N-isopropyl acrylamide (PNIPAAm) exhibits lower critical solution temperature (LCST) and is known to undergo phase transition when the temperature is raised from room temperature to about 32 aC.Experiments were performed to graft PNIPAAm onto cotton fabric. Significant amount of grafting of the polymer on the fabric was observed, and the samples were characterized using SEM and FTIR. The performance of these grafted cotton fabrics was studied and the fabric shows considerable changes in the wettability above and below the LCST of the PNIPAAm polymer. The PNIPAAm grafted cotton fabric is hydrophilic below 32 aC and hydrophobic above 32 aC. The contact angle of the PNIPAAm polymer was also studied, and the angle was found to be increasing as the temperature exceeds the LCST of the PNIPAAm polymer. The PNIPAAm polymer was colored using acid dyes, and these colored gels were grafted onto the cotton fabric. The colored PNIPAAm grafted cotton fabric showed a considerable color difference when measured with the spectrophotometer based on CIELAB system. The reflectance values of these samples were found to decrease as the temperature of the colored PNIPAAm grafted cotton fabric exceeded the LCST of PNIPAAm polymer.
Should the draft chimpanzee sequence be finished?
Taudien, Stefan; Ebersberger, Ingo; Glöckner, Gernot; Platzer, Matthias
Owing to the availability of genome working drafts (WDs), current comparative-sequence studies are frequently performed on a genome-wide scale. In this article, we appraise the utility of WD sequences in the detection of genomic differences in closely related species. We compared human DNA sequences with draft and high-quality versions of the corresponding chimpanzee loci to reveal the overall high quality of the chimp WD sequence. Nevertheless, a significant proportion of the differences between WD and high-quality sequences we observed can be attributed to sequencing errors in the draft. Although we suggest methods to reduce the number of such false positives efficiently, our study emphasizes the benefit expected from finishing the chimpanzee genome sequence. PMID:16406850
Zhang, Yan; Wang, Hongzhi; Yang, Zhongsheng; Li, Jianzhong
The quality of data plays an important role in business analysis and decision making, and data accuracy is an important aspect in data quality. Thus one necessary task for data quality management is to evaluate the accuracy of the data. And in order to solve the problem that the accuracy of the whole data set is low while a useful part may be high, it is also necessary to evaluate the accuracy of the query results, called relative accuracy. However, as far as we know, neither measure nor effective methods for the accuracy evaluation methods are proposed. Motivated by this, for relative accuracy evaluation, we propose a systematic method. We design a relative accuracy evaluation framework for relational databases based on a new metric to measure the accuracy using statistics. We apply the methods to evaluate the precision and recall of basic queries, which show the result's relative accuracy. We also propose the method to handle data update and to improve accuracy evaluation using functional dependencies. Extensive experimental results show the effectiveness and efficiency of our proposed framework and algorithms. PMID:25133752
Zhang, Yan; Wang, Hongzhi; Yang, Zhongsheng; Li, Jianzhong
The quality of data plays an important role in business analysis and decision making, and data accuracy is an important aspect in data quality. Thus one necessary task for data quality management is to evaluate the accuracy of the data. And in order to solve the problem that the accuracy of the whole data set is low while a useful part may be high, it is also necessary to evaluate the accuracy of the query results, called relative accuracy. However, as far as we know, neither measure nor effective methods for the accuracy evaluation methods are proposed. Motivated by this, for relative accuracy evaluation, we propose a systematic method. We design a relative accuracy evaluation framework for relational databases based on a new metric to measure the accuracy using statistics. We apply the methods to evaluate the precision and recall of basic queries, which show the result's relative accuracy. We also propose the method to handle data update and to improve accuracy evaluation using functional dependencies. Extensive experimental results show the effectiveness and efficiency of our proposed framework and algorithms. PMID:25133752
[Automatic polishing of dental prostheses. 1. Development of a centrifugal barrel finishing apparatus].
Tamaki, Y; Miyazaki, T; Aoyama, N; Suzuki, E; Miyaji, T
A centrifugal barrel finishing apparatus with a variable turn table rotational speed (250-1,000 rpm) was newly developed and barrel finishing of Ni-Cr casting plates (10 x 10 x 2 mm) was performed using alumina base chips. When using the sample with a mirror face the amount of polishing and the surface roughness increased and the surface gloss decreased with the increase in rotation speed. A high rotational speed was useful for coarse polishing and low rotational speed was useful for fine polishing. The continuous barrel polishing was trially performed using the sample prepared by the carborundum wheel under variable rotational speed. Automatic polishing to fine polishing could be done using this apparatus. PMID:2133366
Development of new bound abrasive polishers for final finishing of optical glasses
NASA Astrophysics Data System (ADS)
Puchebner, Birgit E.; Jacobs, Stephen D.
Because there are no practical commercially available bound abrasive polishing media, we are developing a bound abrasive polisher for deterministic finishing of optical glasses. Several in- house formulated polishing pellets, molded laps, and ring tools have been studied. Two experimental test beds were employed. The first involved the polishing of flat optical glass parts on single pellet and molded pellet laps. The tests were conducted on a single spindle machine. The performance of in-house manufactured laps was compared to experimental and commercial formulations obtained from industry. Compositions which polished the glass below 20 angstrom rms surface roughness were selected for additional testing. The second test bed for these formulations was the Opticam SM. Materials were molded into a ring tool geometry. Although the tools polished effectively, more work is required to control surface figure during final finishing.
LLNL metal finishing and pollution prevention activities with small businesses
Dini, J.W.; Steffani, C.P.
The Metal Finishing Facility at LLNL has emphasized using environmentally conscious manufacturing principles. Key focus items included minimizing hazardous wastes, minimization of water usage, material and process substitutions, and recycling. Joint efforts with NCAMF (Northern California Association of Metal Finishers), Technic, Inc., EPA, and UC Davis, all directed at pollution prevention, are reviewed.
27 CFR 19.751 - Records of finished products.
Code of Federal Regulations, 2010 CFR
... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Records of finished products. 19.751 Section 19.751 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE... Account § 19.751 Records of finished products. Each processor shall maintain by proof gallons...
7 CFR 58.525 - Storage of finished product.
Code of Federal Regulations, 2010 CFR
... 7 Agriculture 3 2010-01-01 2010-01-01 false Storage of finished product. 58.525 Section 58.525 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Procedures § 58.525 Storage of finished product. Cottage cheese after packaging shall be promptly stored at...
Salmonella infection and immune response in finishing pigs
Technology Transfer Automated Retrieval System (TEKTRAN)
Finishing pigs infected with Salmonella pose significant food safety risks by carrying the pathogen into abattoirs. A study was conducted to determine the dynamic of Salmonella infection in finishing pigs, and the immunological alterations that occur in Salmonella-carrier pigs, by longitudinally com...
This report describes the feasibility of a rinse-and-recovery system that can be installed in almost any metal finishing line and does not harm the environment because no plating solution exits to the sewer. Most toxic pollutants from metal finishing operations are associated wit...
16 CFR 1508.7 - Construction and finishing.
Code of Federal Regulations, 2011 CFR
... 16 Commercial Practices 2 2011-01-01 2011-01-01 false Construction and finishing. 1508.7 Section 1508.7 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL HAZARDOUS SUBSTANCES ACT REGULATIONS REQUIREMENTS FOR FULL-SIZE BABY CRIBS § 1508.7 Construction and finishing. (a) All wood...
To help metal finishing facilities meet the goal of profitable pollution prevention, the USEPA is developing the Metal Finishing Facility Pollution Prevention Tool (MFFP2T), a computer program that estimates the rate of solid, liquid waste generation and air emissions. This progr...
Plutonium finishing plant safety systems and equipment list
Bergquist, G.G.
The Safety Equipment List (SEL) supports Analysis Report (FSAR), WHC-SD-CP-SAR-021 and the Plutonium Finishing Plant Operational Safety Requirements (OSRs), WHC-SD-CP-OSR-010. The SEL is a breakdown and classification of all Safety Class 1, 2, and 3 equipment, components, or system at the Plutonium Finishing Plant complex.
In Vivo, Transcutaneous Glucose Sensing Using Surface-Enhanced Spatially Offset Raman Spectroscopy: Multiple Rats, Improved Hypoglycemic Accuracy, Low Incident Power, and Continuous Monitoring for Greater Than 17 Days
Ma, Ke; Yuen, Jonathan M.; Shah, Nilam C.; Walsh, Joseph T.; Glucksberg, Matthew R.; Van Duyne, Richard P.
This paper presents the latest progress on quantitative, in vivo, transcutaneous glucose sensing using surface enhanced spatially offset Raman spectroscopy (SESORS). Silver film over nanosphere (AgFON) surfaces were functionalized with a mixed self-assembled monolayer (SAM) and implanted subcutaneously in Sprague-Dawley rats. The glucose concentration was monitored in the interstitial fluid of six separate rats. The results demonstrated excellent accuracy and consistency. Remarkably, the root mean square error of calibration (RMSEC) (3.6 mg/dL) and the root mean square error of prediction (RMSEP) (13.7 mg/dL) for low glucose concentration (< 80 mg/dL) is lower than the current International Organization Standard (ISO/DIS 15197) requirements. None of the commercially available glucose sensing techniques can achieve enough accuracy during hypoglycemic episodes. Additionally, our sensor demonstrated functionality up 17 days after implantation, including 12 days under the laser safety level for human skin exposure with only one time calibration. Therefore, our SERS based sensor shows promise for the challenge of reliable continuous glucose sensing systems for optimal glycemic control. PMID:22007689
Protein sources for finishing calves as affected by management system.
Sindt, M H; Stock, R A; Klopfenstein, T J; Vieselmeyer, B A
Two beef production systems were evaluated in conjunction with an evaluation of escape protein sources for finishing calves. Two hundred forty crossbred steers and 80 crossbred heifer calves (BW = 267 +/- 2 kg) were split into two groups: 1) control, finished (207 d) after a 3-wk feedlot adjustment period and 2) grazing cornstalks for 74 d after a 3-wk feedlot adjustment period, then finished (164 d). Finishing treatments were sources and proportions of supplemental CP: 1) urea 100%; 2) soybean meal (SBM) 100%; 3) blood meal (BM) 50%, urea 50%; 4) feather meal (FTH) 50%, urea 50%; 5) SBM 50%, FTH 25%, urea 25%; 6) SBM 25%, FTH 38%, urea 37%; 7) FTH 25%, BM 25%, urea 50%, and 8) FTH 38%, BM 13%, urea 50%. Treatments 1 to 8 were fed in dry-rolled corn (DRC)-based diets. Treatments 9 and 10 were supplement Treatments 1 and 7 fed in diets based on high-moisture corn. Calves finished after a 74-d period of grazing cornstalks consumed more feed (P < .01) and gained faster (P < .01) but were less efficient (P < .05) than calves finished directly after weaning. Although not statistically different, calves finished after grazing cornstalks and supplemented with natural protein in the feedlot were 7% more efficient than calves supplemented with urea alone. Efficiency of calves finished directly after weaning was similar for calves supplemented with natural protein or urea alone. Supplementing SBM/FTH/urea or BM/FTH/urea improved feed efficiency compared with supplementing FTH/urea alone. These data suggest that allowing calves to graze cornstalks before finishing is a possible management option, but this system may require more metabolizable protein in the finishing diet to maximize feed efficiency if the calves are expressing compensatory growth. PMID:8463161
Pollution prevention and water conservation in metals finishing operations
O`Shaughnessy, J.; Clark, W.; Lizotte, R.P. Jr.; Mikutel, D.
Attleboro, Massachusetts is the headquarters of the Materials and Controls Group of Texas Instruments Incorporated (Texas Instruments). In support of their activities, Texas Instruments operates a number of metal finishing and electroplating processes. The water supply and the wastewater treatment requirements are supplied throughout the facility from a central location. Water supply quality requirements varies with each manufacturing operation. As a result, manufacturing operations are classified as either high level or a lower water quality. The facility has two methods of wastewater treatment and disposal. The first method involves hydroxide and sulfide metals precipitation prior to discharge to a surface water. The second method involves metals precipitation, filtration, and discharge via sewer to the Attleboro WTF. The facility is limited to a maximum wastewater discharge of 460,000 gallons per day to surface water under the existing National Pollution Discharge Elimination System (NPDES) permit. There is also a hydraulic flow restriction on pretreated wastewater that is discharged to the Attleboro WTF. Both of these restrictions combined with increased production could cause the facility to reach the treatment capacity. The net effect is that wastewater discharge problems are becoming restrictive to the company`s growth. This paper reviews Texas Instruments efforts to overcome these restrictions through pollution prevention and reuse practices rather than expansion of end of pipe treatment methods.
Effect of forage species during finishing on growth rate, final weight and carcass parameters from pasture finished cattle
Technology Transfer Automated Retrieval System (TEKTRAN)
In 2005 and 2006, angus-crossbred steers (n = 72) were used to compare growth rate, final weight and carcass parameters from pasture-finished cattle grazing cool-season mixed (MP), alfalfa (AL), or pearl millet (PM) pastures during the final 44 d of finishing. Steers were harvested on the same dates...
The Role of Nanodiamonds in the Polishing Zone During Magnetorheological Finishing (MRF)
DeGroote, J.E.; Marino, A.E.; WIlson, J.P.; Bishop, A.L.; Jacobs, S.D.
In this work we discuss the role that nanodiamond abrasives play in magnetorheological finishing. We hypothesize that, as the nanodiamond MR fluid is introduced to the magnetic field, the micron sized spherical carbonyl iron (CI) particles are pulled down towards the rotating wheel, leaving a thin layer of nanodiamonds at the surface of the stiffened MR fluid ribbon. Our experimental results shown here support this hypothesis. We also show that surface roughness values inside MRF spots show a strong correlation with the near surface mechanical properties of the glass substrates and with drag force.
Automated finishing of diamond turned dies for hard x-ray and EUV optics replication
NASA Astrophysics Data System (ADS)
Beaucamp, Anthony T. H.; Namba, Yoshiharu; Freeman, Richard R.
Ultra-precision diamond turning can deliver very accurate form, often less than 100nm P-V. A possible manufacturing method for thin Wolter type-1 mirrors in hard X-ray space telescopes thus involves generating electroless nickel plated mandrels by diamond turning, before coating them with a reflective film and substrate. However, the surface texture after turning falls far short from the requirements of X-ray and EUV applications. The machining marks need to be removed, with hand polishing still widely employed. There is thus a compelling need for automated finishing of turned dies. A two step finishing method is presented that combines fluid jet and precessed bonnet polishing on a common 7-axis CNC platform. This method is capable of finishing diamond turned electroless nickel plated dies down to 0.28nm rms roughness, while deterministically improving form error down to 30nm P-V. The fluid jet polishing process, which consists of pressurizing water and abrasive particles for delivery through a nozzle, has been specially optimized with a newly designed slurry delivery unit and computer simulations, to remove diamond turning marks without introducing another waviness signature. The precessed bonnet polishing method, which consists of an inflated membrane rotated at an angle from the local normal to the surface and controlled by geometrical position relative to the work-piece, is subsequently employed with a novel control algorithm to deliver scratch-free surface roughness down to 0.28 nm rms. The combination of these two deterministic processes to finish aspheric and freeform dies promises to unlock new frontiers in X-ray and EUV optics fabrication.
Magnetorheological finishing (MRF) of potassium dihydrogen phosphate (KDP) crystals: nonaqueous fluids development, optical finish, and laser damage performance at 1064 nm and 532 nm
NASA Astrophysics Data System (ADS)
Menapace, J. A.; Ehrmann, P. R.; Bickel, R. C.
Over the past year we have been working on specialized MR fluids for polishing KDP crystals. KDP is an extremely difficult material to conventionally polish due to its water solubility, low hardness, and temperature sensitivity. Today, KDP crystals are finished using single-point diamond turning (SPDT) tools and nonaqueous lubricants/coolants. KDP optics fabricated using SPDT, however, are limited to surface corrections due to tool/method characteristics with surface quality driven by microroughness from machine pitch, speed, force, and diamond tool character. MRF polishing offers a means to circumvent many of these issues since it is deterministic which makes the technique practical for surface and transmitted wavefront correction, is low force, and is temperature independent. What is lacking is a usable nonaqueous MR fluid that is chemically and physically compatible with KDP which can be used for polishing and subsequently cleaned from the optical surface. In this study, we will present the fluid parameters important in the design and development of nonaqueous MR fluid formulations capable of polishing KDP and how these parameters affect MRF polishing. We will also discuss requirements peculiar to successful KDP polishing and how they affect optical figure/finish and laser damage performance at 1064 nm and 532 nm.
Magnetorheological finishing (MRF) of potassium dihydrogen phosphate (KDP) crystals: nonaqueous fluids development, optical finish, and laser damage performance at 1064 nm and 532 nm
Menapace, J A; Ehrmann, P R; Bickel, R C
Over the past year we have been working on specialized MR fluids for polishing KDP crystals. KDP is an extremely difficult material to conventionally polish due to its water solubility, low hardness, and temperature sensitivity. Today, KDP crystals are finished using single-point diamond turning (SPDT) tools and nonaqueous lubricants/coolants. KDP optics fabricated using SPDT, however, are limited to surface corrections due to tool/method characteristics with surface quality driven by microroughness from machine pitch, speed, force, and diamond tool character. MRF polishing offers a means to circumvent many of these issues since it is deterministic which makes the technique practical for surface and transmitted wavefront correction, is low force, and is temperature independent. What is lacking is a usable nonaqueous MR fluid that is chemically and physically compatible with KDP which can be used for polishing and subsequently cleaned from the optical surface. In this study, we will present the fluid parameters important in the design and development of nonaqueous MR fluid formulations capable of polishing KDP and how these parameters affect MRF polishing. We will also discuss requirements peculiar to successful KDP polishing and how they affect optical figure/finish and laser damage performance at 1064 nm and 532 nm.
Developments in the finishing of domes and conformal optics
NASA Astrophysics Data System (ADS)
Shorey, Aric B.; Kordonski, William; Tracy, Justin; Tricard, Marc
The final finish and characterization of windows and domes presents a number of difficult challenges. Furthermore, there is a desire to incorporate conformal shapes into next generation imaging and surveillance systems to provide significant advantages in overall component performance. Unfortunately, their constantly changing curvature and steep slopes make fabrication of such shapes incompatible with most conventional polishing and metrology solutions. Two novel types of polishing technology, Magnetorheological Finishing (MRF®) and Magnetorheological Jet (MR Jet TM), along with metrology provided by the Sub-aperture Stitching Interferometer (SSI®) have several unique attributes that give them advantages in enhancing fabrication of hemispherical domes and even conformal shapes. The advantages that MRF brings to the precision finishing of a wide range of shapes such as flats, spheres (including hemispheres), cylinders, aspheres and even freeform optics, has been well documented. The recently developed MR Jet process provides additional benefits, particularly in the finishing the inside of steep concave domes and other irregular shapes. Combining these technologies with metrology techniques, such as the SSI, provides a solution for finishing current and future windows and domes. Recent exciting developments in the finishing of such shapes with these technologies will be presented. These include new advances such as the ability to use the SSI to characterize a range of shapes such as domes and aspheres, as well as progress in using MRF and MR Jet for finishing conventional and conformal windows and domes.
Plutonium Finishing Plant safety evaluation report
Not Available
The Plutonium Finishing Plant (PFP) previously known as the Plutonium Process and Storage Facility, or Z-Plant, was built and put into operation in 1949. Since 1949 PFP has been used for various processing missions, including plutonium purification, oxide production, metal production, parts fabrication, plutonium recovery, and the recovery of americium (Am-241). The PFP has also been used for receipt and large scale storage of plutonium scrap and product materials. The PFP Final Safety Analysis Report (FSAR) was prepared by WHC to document the hazards associated with the facility, present safety analyses of potential accident scenarios, and demonstrate the adequacy of safety class structures, systems, and components (SSCs) and operational safety requirements (OSRs) necessary to eliminate, control, or mitigate the identified hazards. Documented in this Safety Evaluation Report (SER) is DOE`s independent review and evaluation of the PFP FSAR and the basis for approval of the PFP FSAR. The evaluation is presented in a format that parallels the format of the PFP FSAR. As an aid to the reactor, a list of acronyms has been included at the beginning of this report. The DOE review concluded that the risks associated with conducting plutonium handling, processing, and storage operations within PFP facilities, as described in the PFP FSAR, are acceptable, since the accident safety analyses associated with these activities meet the WHC risk acceptance guidelines and DOE safety goals in SEN-35-91.
Protein requirements of finishing paca (Cuniculus paca).
Nogueira-Filho, Sérgio Luiz Gama; Bastos, Ivanise da Hora; Mendes, Alcester; Nogueira, Selene Siqueira da Cunha
We conducted a nitrogen balance digestion trial to determine the crude protein requirements of paca (Cuniculus paca) during the last growth phase. In a 4 × 4 Latin square design, four young captive male pacas, aged 5 months, were fed four isoenergetic diets containing four different levels of nitrogen (N) (11.3, 16.6, 21.4, and 26.6 g N/kg of dry matter). After 15 days of adaptation, we collected all feces and urine for five consecutive days. By regression analysis between N intake and N in feces and urine, the metabolic fecal nitrogen (MFN = 4.2 g/kg of dry matter intake) and daily endogenous urinary N (EUN = 91.6 mg/kg(0.75)) were determined. Likewise, by regression analyses between nitrogen intake and nitrogen retention [NR = N intake-(fecal N + urine N)], we estimated the daily requirement of 280.5 mg N/kg(0.75). Therefore, a minimum of 55 g crude protein per kilogram dry matter and 13 MJ/kg of digestible energy are required by finishing paca on unrestricted diets. Such values are similar to those of other wild frugivores and below those of growing rabbits. The data confirm that farmers overfeed protein, and similar growth can be more economically achieved on lower protein diets. PMID:27026234
[Drag-out in metal finishing industries].
Laforest, V; Piatyszek, E; Mojaat, W; Bourgois, J
Currently, environmental regulations induce industrialists to implement source reduction techniques in order to comply with the prevention principle toward sustainable development. The project PIPSI (PIlotage Propre des Systèmes Industriels/industrial system dean piloting) financing by Rhone-Alps Region is carried out with the aim to contribute to this objective. The study presented in this article concerns the pollution transfer in a metal finishing treatment line in order to minimise the environmental impact obtained notably with the pollution balance. Drag-out and draining phenomena have been particularly studied. Results obtained showed that a 10 seconds of draining reduced drag-out from 65 to 85% in terms of pieces design. Moreover, during the experiments, 5 drag-out levels were identified by medium values from 26 to 1700 ml m(-2). So that, either a piece can be associated to a level or knowing the piece drag-out level, it is possible to evaluate its medium drag-out value. Then the pollution balance will be obtained more easily. PMID:16342539
Metal finishing wastewater pressure filter optimization
Norford, S.W.; Diener, G.A.; Martin, H.L.
The 300-M Area Liquid Effluent Treatment Facility (LETF) of the Savannah River Site (SRS) is an end-of-pipe industrial wastewater treatment facility, that uses precipitation and filtration which is the EPA Best Available Technology economically achievable for a Metal Finishing and Aluminum Form Industries. The LETF consists of three close-coupled treatment facilities: the Dilute Effluent Treatment Facility (DETF), which uses wastewater equalization, physical/chemical precipitation, flocculation, and filtration; the Chemical Treatment Facility (CTF), which slurries the filter cake generated from the DETF and pumps it to interim-StatuS RCRA storage tanks; and the Interim Treatment/Storage Facility (IT/SF) which stores the waste from the CTF until the waste is stabilized/solidified for permanent disposal, 85% of the stored waste is from past nickel plating and aluminum canning of depleted uranium targets for the SRS nuclear reactors. Waste minimization and filtration efficiency are key to cost effective treatment of the supernate, because the waste filter cake generated is returned to the IT/SF. The DETF has been successfully optimized to achieve maximum efficiency and to minimize waste generation.
Metal finishing wastewater pressure filter optimization
Norford, S.W.; Diener, G.A.; Martin, H.L.
The 300-M Area Liquid Effluent Treatment Facility (LETF) of the Savannah River Site (SRS) is an end-of-pipe industrial wastewater treatment facility, that uses precipitation and filtration which is the EPA Best Available Technology economically achievable for a Metal Finishing and Aluminum Form Industries. The LETF consists of three close-coupled treatment facilities: the Dilute Effluent Treatment Facility (DETF), which uses wastewater equalization, physical/chemical precipitation, flocculation, and filtration; the Chemical Treatment Facility (CTF), which slurries the filter cake generated from the DETF and pumps it to interim-StatuS RCRA storage tanks; and the Interim Treatment/Storage Facility (IT/SF) which stores the waste from the CTF until the waste is stabilized/solidified for permanent disposal, 85% of the stored waste is from past nickel plating and aluminum canning of depleted uranium targets for the SRS nuclear reactors. Waste minimization and filtration efficiency are key to cost effective treatment of the supernate, because the waste filter cake generated is returned to the IT/SF. The DETF has been successfully optimized to achieve maximum efficiency and to minimize waste generation.
Assessing the accuracy of 1-D analytical heat tracing for estimating near-surface sediment thermal diffusivity and water flux under transient conditions
NASA Astrophysics Data System (ADS)
Rau, Gabriel C.; Cuthbert, Mark O.; McCallum, Andrew M.; Halloran, Landon J. S.; Andersen, Martin S.
Amplitude decay and phase delay of oscillating temperature records measured at two vertical locations in near-surface sediments can be used to infer water fluxes, thermal diffusivity, and sediment scour/deposition. While methods that rely on the harmonics-based analytical heat transport solution assume a steady state water flux, many applications have reported transient fluxes but ignored the possible violation of this assumption in the method. Here we use natural heat tracing as an example to investigate the extent to which changes in the water flux, and associated temperature signal nonstationarity, can be separated from other influences. We systematically scrutinize the assumption of steady state flow in analytical heat tracing and test the capabilities of the method to detect the timing and magnitude of flux transients. A numerical model was used to synthesize the temperature response to different step and ramp changes in advective thermal velocity magnitude and direction for both a single-frequency and multifrequency temperature boundary. Time-variable temperature amplitude and phase information were extracted from the model output with different signal-processing methods. We show that a worst-case transient flux induces a temperature nonstationarity, the duration of which is less than 1 cycle for realistic sediment thermal diffusivities between 0.02 and 0.13 m2/d. However, common signal-processing methods introduce erroneous temporal spreading of advective thermal velocities and significant anomalies in thermal diffusivities or sensor spacing, which is used as an analogue for streambed scour/deposition. The most time-variant spectral filter can introduce errors of up to 57% in velocity and 33% in thermal diffusivity values with artifacts spanning ±2 days around the occurrence of rapid changes in flux. Further, our results show that analytical heat tracing is unable to accurately resolve highly time-variant fluxes and thermal diffusivities and does not allow
40 CFR 463.30 - Applicability; description of the finishing water subcategory.
Code of Federal Regulations, 2010 CFR
... (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS PLASTICS MOLDING AND FORMING POINT SOURCE CATEGORY Finishing... the finishing water subcategory are processes where water comes in contact with the plastic...
40 CFR 463.30 - Applicability; description of the finishing water subcategory.
Code of Federal Regulations, 2011 CFR
... (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS PLASTICS MOLDING AND FORMING POINT SOURCE CATEGORY Finishing... the finishing water subcategory are processes where water comes in contact with the plastic...
40 CFR 425.90 - Applicability; description of the retan-wet finish-splits subcategory.
Code of Federal Regulations, 2011 CFR
... PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS LEATHER TANNING AND FINISHING POINT SOURCE... resulting from any tannery which processes previously unhaired and tanned splits into finished leather...
40 CFR 425.90 - Applicability; description of the retan-wet finish-splits subcategory.
Code of Federal Regulations, 2010 CFR
... PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS LEATHER TANNING AND FINISHING POINT SOURCE... resulting from any tannery which processes previously unhaired and tanned splits into finished leather...
An overview of plastic optical fiber end finishers at Fermilab
Mishina, M.; Lindenmeyer, C.; Korienek, J.
Several years ago the need for equipment to precisely finish the ends of plastic optical fibers was recognized. Many high energy physics experiments use thousands of these fibers which must be polished on one or both ends. A fast, easy-to-operate machine yielding repeatable finishes was needed. Three types of machines were designed and constructed that are in daily use at Fermilab, all finish the fiber ends by flycutting with a diamond tool. Althrough diamond flycutting of plastic is not new, the size and fragility of plastic optical fibers present several challenges.
Structure and kinetics of Sn whisker growth on Pb-free solder finish
Choi, W.J.; Lee, T.Y.; Tu, K.N.; Tamura, N.; Celestre, R.S.; MacDowell, A.A.; Bong, Y.Y.; Nguyen, L.; Sheng, G.T.T.
Standard Leadframes used in surface mount technology are finished with a layer of eutectic SnPb for passivation and for enhancing solder wetting during reflow. When eutectic SnPb is replaced by Pb-free solder, especially the eutectic SnCu, a large number of Sn whiskers are found on the Pb-free finish. Some of the whiskers are long enough to become shorts between the neighboring legs of the leadframe. How to suppress their growth and how to perform accelerated test of Sn whisker growth are crucial reliability issues in the electronic packaging industry. In this paper, we report the study of spontaneous Sn whisker growth at room temperature on eutectic SnCu and pure Sn finishes. Both compressive stress and surface oxide on Sn are necessary conditions for whisker growth. Structure and stress analyses by using the micro-diffraction in synchrotron radiation are reported. Cross-sectional electron microscopy, with samples prepared by focused ion beam, are included.
Study of a wheel-like electrorheological finishing tool and its applications to small parts.
Su, Jingshi; Cheng, Haobo; Feng, Yunpeng; Tam, Hon-Yuen
A wheel-like electrorheological finishing (ERF) tool for small parts polishing is proposed and thoroughly studied. First, the electrorheological polishing fluid is tested, and its properties suggest usability for electrorheological fluid-assisted finishing. Then, the mathematical removal model of the ERF tool is built employing the conformal mapping method and high-order multipolar moment theory. Finally, a micropattern of trough is fabricated on a slide glass (7 mm wide and 1 mm thick). The trough is 70 nm deep, and its flat bottom is 1.5 m wide (peak to valley of 3.16 nm and root mean square of 1.27 nm); the surface roughness finally achieves 0.86 nm. The results demonstrate the stable machining capability of the ERF tool for miniature parts. PMID:26836063
Biotreatment on cellulose fluff pulp: quaternary ammonium salts finish and grafting with beta-cyclodextrin.
Ghemati, Djamila; Oudia, Atika; Aliouche, Djamel; Lamouri, Saad
For its potential performances to be expanded, cellulose needs to be processed in different ways. Therefore, an object of the present work was to provide a chemical modification of cellulose through: a specific finish with two quaternary ammonium salts (namely Aliquat 336 and Aliquat 1529, respectively). Chemical grafting of beta-cyclodextrin derivative (beta-CD) onto fibers followed by the inclusion of benzoic acid in the grafted CD cavities as a probe chemical. Physicochemical properties and performances of the untreated and treated fibers have been determined with infrared spectra, microscopy, swelling measurements, antimicrobial finishing tests, and dye adsorption. Our results show that cellulose fibers can be efficiently modified with no significant changes in its structural and surface properties; the treated fibers show an attractive behavior in swelling, dye adsorption and antibacterial activity. PMID:19089647
Classification and storage of wastewater from floor finish removal operations
Hunt, C.E.
This study evaluates the wastewater generated from hard surface floor finish removal operations at Lawrence Livermore Laboratory in order to determine if this wastewater is a hazardous waste, either by statistical evaluation, or other measurable regulatory guidelines established in California Regulations. This research also comparatively evaluates the 55 gallon drum and other portable tanks, all less than 1,000 gallons in size in order to determine which is most effective for the management of this waste stream at Lawrence Livermore Laboratory. The statistical methods in SW-846 were found to be scientifically questionable in their application to hazardous waste determination. In this statistical evaluation, the different data transformations discussed in the regulatory guidance document were applied along with the log transformation to the population of 18 samples from 55 gallon drums. Although this statistical evaluation proved awkward in its application, once the data is collected and organized on a spreadsheet this statistical analysis can be an effective tool which can aid the environmental manager in the hazardous waste classification process.
Multifunctional finishing of cellulosic/polyester blended fabrics.
Ibrahim, N A; Eid, B M; Youssef, M A; Ibrahim, H M; Ameen, H A; Salah, A M
Innovative/efficient finishing systems for imparting multi-functional properties to cotton/polyester and viscose/polyester blends were developed. Factors affecting the extent of functionalization including type and concentration of the nano-hybrid, i.e. silver nanoparticles/polyvinyl pyrolidone hybrid (Ag-NP's/PVP) or zinc oxide nanoparticles/hyperbranched polyamide-amine hybrid (ZnO-NP's/HBPAA), concentration of Basic Blue 9, or chitosan and sequence of treatment using citric acid as cross-linker were reported. Loading of β-CD, with its hydrophobic cavities, onto the cross-linked substrates and subsequent treatment with Neem-oil, Lavender-oil or 4-hydroxybenzophenone was also studied. The obtained products exhibit a remarkable easy care, antibacterial and/or UV-blocking functional properties. The improvement in the imparted properties and durability to wash is governed by type and amount of loaded active ingredients. Mode of interactions was suggested, and surface modifications together with composition of selected samples were also confirmed by SEM images and EDX spectra. PMID:23911516
This project involved precipitating heavy metals normally present in metal finishing wastewaters by a novel process which employs ferrous sulfide addition (Sulfex), as well as by conventional treatment using calcium hydroxide for comparison purposes. These studies consisted of la...
2. DETAIL VIEW OF JOURNAL LATHE, AXLE FINISHING AREA. Grinding ...
Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey
2. DETAIL VIEW OF JOURNAL LATHE, AXLE FINISHING AREA. Grinding bearing diameters on locomotive axle. Norton grinder, 1942 (dated). Melvin Grassmeyer, operator. - Juniata Shops, Machine Shop No. 1, East of Fourth Avenue at Third Street, Altoona, Blair County, PA
3. DETAIL VIEW OF JOURNAL LATHE, AXLE FINISHING AREA. Grinding ...
Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey
3. DETAIL VIEW OF JOURNAL LATHE, AXLE FINISHING AREA. Grinding bearing diameters on locomotive axle. Norton grinder, 1942 (dated). Melvin Grassmeyer, operator. - Juniata Shops, Machine Shop No. 1, East of Fourth Avenue at Third Street, Altoona, Blair County, PA
Klebsiella strains are found in abnormally high numbers in a stream receiving wastewater from a textile finishing plant. Representative strains are randomly selected to determine biochemical, serotype, and virulence patterns. All strains conform to the commonly accepted biochemic...
Hardening/finishing treatment of compressor blades using a machine with planetary container motion
NASA Astrophysics Data System (ADS)
Shpatakovskii, A. F.
A process for the hardening and finishing of high-pressure compressor blades for aircraft powerplants is described whereby the blades are placed in containers that move along a planetary path in a hardening medium consisting of steel balls. The extent of surface hardening, surface roughness, and residual stresses are determined for specimens of U8A steel and blades of EP718VD alloy treated under different conditions. The efficiency of the treatment in terms of increased blade durability and productivity is estimated.
8. Finish line, marked by white poles, as viewed from ...
Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey
8. Finish line, marked by white poles, as viewed from infield tote board. Shown are all the best locations for viewing the finish line, including the Clubhouse on the left and Original Grandstand on the right. For a similar view taken in 1939 by a photographer for the Seattle Post-Intelligencer newspaper, see photo WA-201-24. (August 1993) - Longacres, 1621 Southwest Sixteenth Street, Renton, King County, WA
Bureau of Indian Affairs Schools: New Facilities Management Information System Promising, but Improved Data Accuracy Needed.
ERIC Educational Resources Information Center
General Accounting Office, Washington, DC.
A General Accounting Office (GAO) study evaluated the Bureau of Indian Affairs' (BIA) new facilities management information system (FMIS). Specifically, the study examined whether the new FMIS addresses the old system's weaknesses and meets BIA's management needs, whether BIA has finished validating the accuracy of data transferred from the old…
Increasing Accuracy in Computed Inviscid Boundary Conditions
NASA Technical Reports Server (NTRS)
Dyson, Roger
A technique has been devised to increase the accuracy of computational simulations of flows of inviscid fluids by increasing the accuracy with which surface boundary conditions are represented. This technique is expected to be especially beneficial for computational aeroacoustics, wherein it enables proper accounting, not only for acoustic waves, but also for vorticity and entropy waves, at surfaces. Heretofore, inviscid nonlinear surface boundary conditions have been limited to third-order accuracy in time for stationary surfaces and to first-order accuracy in time for moving surfaces. For steady-state calculations, it may be possible to achieve higher accuracy in space, but high accuracy in time is needed for efficient simulation of multiscale unsteady flow phenomena. The present technique is the first surface treatment that provides the needed high accuracy through proper accounting of higher-order time derivatives. The present technique is founded on a method known in art as the Hermitian modified solution approximation (MESA) scheme. This is because high time accuracy at a surface depends upon, among other things, correction of the spatial cross-derivatives of flow variables, and many of these cross-derivatives are included explicitly on the computational grid in the MESA scheme. (Alternatively, a related method other than the MESA scheme could be used, as long as the method involves consistent application of the effects of the cross-derivatives.) While the mathematical derivation of the present technique is too lengthy and complex to fit within the space available for this article, the technique itself can be characterized in relatively simple terms: The technique involves correction of surface-normal spatial pressure derivatives at a boundary surface to satisfy the governing equations and the boundary conditions and thereby achieve arbitrarily high orders of time accuracy in special cases. The boundary conditions can now include a potentially infinite number
Effect of temperature and O-ring gland finish on sealing ability of Viton V747-75
NASA Technical Reports Server (NTRS)
Lach, Cynthia L.
As a part of the redesign project of the Space Shuttle solid rocket motor (SRM) following the Challenger accident, the field joint was redesigned to minimize the relative joint motion caused by internal motor pressurization during ignition. The O-ring seals and glands for the field joint were designed both to accommodate structural deflections and to promote pressure-assisted sealing. Tests were conducted in various face seal fixtures to evaluate the ability of Viton V747-75 O-rings to seal for a range of temperatures and surface finishes of the redesigned O-ring gland. The effect of surface finish on the sealing performance and wear characteristics of the O-rings was evaluated during simulated launch conditions that included low-frequency vibrations, gap openings, and rapid pressurizations. The effect of contamination on the sealing performance was also investigated. The O-rings sealed throughout the 75 deg F leak check test and for the seal tests from 50 deg F to 120 deg F for the range of surface finishes investigated. Although abrasions were found in the O-rings from pressurization against the rougher finishes, these abrasions were not detrimental to sealing. Below 50 deg F, Viton V747-75 O-rings were insufficiently resilient to track the test gap opening.
Prevalence of clinical signs of disease in Danish finisher pigs.
Petersen, H H; Nielsen, E O; Hassing, A-G; Ersbøll, A K; Nielsen, J P
Between December 1999 and February 2001, two visits, eight weeks apart, were made to 90 herds of Danish finisher pigs. The prevalence of clinical signs was recorded by three veterinary technicians from the Danish Bacon and Meat Council according to a standardised procedure; they had been trained and their observations were monitored and validated before and during the study. A total of 154,347 finisher pigs were examined and 22,136 clinical signs were recorded. Vices accounted for 43 per cent of the signs. The highest mean prevalence was observed for ear necrosis (4.44 per cent), followed by respiratory signs (2.17 per cent), lameness (1.92 per cent), other skin diseases (1.73 per cent), tail bites (1.26 per cent), umbilical hernia (0.78 per cent), flank bites (0.52 per cent), diarrhoea (0.27 per cent), respiratory distress (0.12 per cent), atrophic rhinitis (0.10 per cent), recumbency (0.09 per cent) and central nervous disease (0.05 per cent). The prevalence of atrophic rhinitis was higher in conventional herds than in specific pathogen-free herds. The prevalence of clinical signs of atrophic rhinitis was higher among finishers weighing 51 to 75 kg than among finishers weighing up to 50 kg, and the prevalence of respiratory signs was higher among finishers weighing 51 to 75 kg then among finishers weighing 76 to 100 kg. PMID:18359931
The development of robust accuracy assessment methods for the validation of spatial data represent's a difficult scientific challenge for the geospatial science community. The importance and timeliness of this issue is related directly to the dramatic escalation in the developmen...
Atmospheric pressure plasma polymerization of 1,3-butadiene for hydrophobic finishing of textile substrates
NASA Astrophysics Data System (ADS)
Samanta, Kartick K.; Jassal, Manjeet; Agrawal, Ashwini K.
Atmospheric pressure plasma processing of textile has both ecological and economical advantages over the wet-chemical processing. However, reaction in atmospheric pressure plasma has important challenges to be overcome before it can be successfully used for finishing applications in textile. These challenges are (i) generating stable glow plasma in presence liquid/gaseous monomer, and (ii) keeping the generated radicals active in the presence of contaminants such as oxygen and air. In this study, a stable glow plasma was generated at atmospheric pressure in the mixture of gaseous reactive monomer-1,3-butadiene and He and was made to react with cellulosic textile substrate. After 12 min of plasma treatment, the hydrophilic surface of the cellulosic substrate turned into highly hydrophobic surface. The hydrophobic finish was found to be durable to soap washing. After soap washing, a water drop of 37 μl took around 250 s to get absorbed in the treated sample compared to < 1 s in the untreated samples. The plasma modified samples showed water contact angle of around 134°. Both top and bottom sides of the fabric showed similar hydrophobic results in terms of water absorbency and contact angle. The results may be attributed to chemical reaction of butadiene with the cellulosic textile substrate. The surface characterization of the plasma modified samples under SEM and AFM revealed modification of the surface under <100 nm. The results showed that atmospheric pressure plasma can be successfully used for carrying out reaction of 1,3-butadiene with cellulosic textile substrates for producing hydrophobic surface finish.
NASA Astrophysics Data System (ADS)
Kandel, Daniel; Levinski, Vladimir; Sapiens, Noam; Cohen, Guy; Amit, Eran; Klein, Dana; Vakshtein, Irina
Currently, the performance of overlay metrology is evaluated mainly based on random error contributions such as precision and TIS variability. With the expected shrinkage of the overlay metrology budget to < 0.5nm, it becomes crucial to include also systematic error contributions which affect the accuracy of the metrology. Here we discuss fundamental aspects of overlay accuracy and a methodology to improve accuracy significantly. We identify overlay mark imperfections and their interaction with the metrology technology, as the main source of overlay inaccuracy. The most important type of mark imperfection is mark asymmetry. Overlay mark asymmetry leads to a geometrical ambiguity in the definition of overlay, which can be ~1nm or less. It is shown theoretically and in simulations that the metrology may enhance the effect of overlay mark asymmetry significantly and lead to metrology inaccuracy ~10nm, much larger than the geometrical ambiguity. The analysis is carried out for two different overlay metrology technologies: Imaging overlay and DBO (1st order diffraction based overlay). It is demonstrated that the sensitivity of DBO to overlay mark asymmetry is larger than the sensitivity of imaging overlay. Finally, we show that a recently developed measurement quality metric serves as a valuable tool for improving overlay metrology accuracy. Simulation results demonstrate that the accuracy of imaging overlay can be improved significantly by recipe setup optimized using the quality metric. We conclude that imaging overlay metrology, complemented by appropriate use of measurement quality metric, results in optimal overlay accuracy.
Accuracy of numerically produced compensators.
Thompson, H; Evans, M D; Fallone, B G
A feasibility study is performed to assess the utility of a computer numerically controlled (CNC) mill to produce compensating filters for conventional clinical use and for the delivery of intensity-modulated beams. A computer aided machining (CAM) software is used to assist in the design and construction of such filters. Geometric measurements of stepped and wedged surfaces are made to examine the accuracy of surface milling. Molds are milled and filled with molten alloy to produce filters, and both the molds and filters are examined for consistency and accuracy. Results show that the deviation of the filter surfaces from design does not exceed 1.5%. The effective attenuation coefficient is measured for CadFree, a cadmium-free alloy, in a 6 MV photon beam. The effective attenuation coefficients at the depth of maximum dose (1.5 cm) and at 10 cm in solid water phantom are found to be 0.546 cm-1 and 0.522 cm-1, respectively. Further attenuation measurements are made with Cerrobend to assess the variations of the effective attenuation coefficient with field size and source-surface distance. The ability of the CNC mill to accurately produce surfaces is verified with dose profile measurements in a 6 MV photon beam. The test phantom is composed of a 10 degrees polystyrene wedge and a 30 degrees polystyrene wedge, presenting both a sharp discontinuity and sloped surfaces. Dose profiles, measured at the depth of compensation (10 cm) beneath the test phantom and beneath a flat phantom, are compared to those produced by a commercial treatment planning system. Agreement between measured and predicted profiles is within 2%, indicating the viability of the system for filter production. PMID:10100166
Activity monitor accuracy in persons using canes.
Wendland, Deborah Michael; Sprigle, Stephen H
The StepWatch activity monitor has not been validated on multiple indoor and outdoor surfaces in a population using ambulation aids. The aims of this technical report are to report on strategies to configure the StepWatch activity monitor on subjects using a cane and to report the accuracy of both leg-mounted and cane-mounted StepWatch devices on people ambulating over different surfaces while using a cane. Sixteen subjects aged 67 to 85 yr (mean 75.6) who regularly use a cane for ambulation participated. StepWatch calibration was performed by adjusting sensitivity and cadence. Following calibration optimization, accuracy was tested on both the leg-mounted and cane-mounted devices on different surfaces, including linoleum, sidewalk, grass, ramp, and stairs. The leg-mounted device had an accuracy of 93.4% across all surfaces, while the cane-mounted device had an aggregate accuracy of 84.7% across all surfaces. Accuracy of the StepWatch on the stairs was significantly less accurate (p < 0.001) when comparing surfaces using repeated measures analysis of variance. When monitoring community mobility, placement of a StepWatch on a person and his/her ambulation aid can accurately document both activity and device use. PMID:23341318
40 CFR 463.30 - Applicability; description of the finishing water subcategory.
Code of Federal Regulations, 2013 CFR
... finishing water subcategory. 463.30 Section 463.30 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Finishing Water Subcategory § 463.30 Applicability; description of the finishing water subcategory. This subpart applies to discharges of pollutants from processes in the finishing water subcategory to waters...
Orthodontic treatment outcomes obtained by application of a finishing protocol
Carvajal-Flórez, Alvaro; Barbosa-Lis, Diana María; Zapata-Noreña, Oscar Arturo; Marín-Velásquez, Julissa Andrea; Afanador-Bayona, Sergio Andrés
ABSTRACT Objective: To evaluate the results of a finishing protocol implemented in patients treated in the Orthodontics graduate program at Universidad de Antioquia. Evaluation was carried out by means of the criteria set by the Objective Grading System (OGS) of the American Board of Orthodontics (ABO). Methods: Cast models and panoramic radiographs of 34 patients were evaluated. The intervention group (IG) consisted of 17 patients (19.88 ± 4.4 years old) treated under a finishing protocol. This protocol included training in finishing, application of a finishing guide, brackets repositioning and patient's follow-up. Results of the IG were compared to a control group of 17 patients (21.88 ± 7.0 years old) selected by stratified randomization without finishing intervention (CG). Results: The scores for both CG and IG were 38.00 ± 9.0 and 31.41 ± 9.6 (p = 0.048), respectively. The score improved significantly in the IG group, mainly regarding marginal ridges (CG: 5.59 ± 2.2; IG: 3.65 ± 1.8) (p = 0.009) and root angulation (CG: 7.59 ± 2.8; IG: 4.88 ± 2.6) (p = 0.007). Criteria that did not improve, but had the highest scores were: alignment (CG: 6.35 ± 2.7; IG: 6.82 ± 2.8) (p = 0.62) and buccolingual inclination (CG: 3.6 ± 5.88; IG: 5.29 ± 3.9) (p = 0.65). Conclusions: Standardization and implementation of a finishing protocol contributed to improve clinical performance in the Orthodontics graduate program, as expressed by occlusal outcomes. Greater emphasis should be given on the finishing phase to achieve lower scores in the ABO grading system. PMID:27275620
Finished Prokaryotic Genome Assemblies from a Low-cost Combination of Short and Long Reads (Seventh Annual Sequencing, Finishing, Analysis in the Future (SFAF) Meeting 2012)
Yin, Shuangye (Broad Institute)
Shuangye Yin on "Finished prokaryotic genome assemblies from a low-cost combination of short and long reads" at the 2012 Sequencing, Finishing, Analysis in the Future Meeting held June 5-7, 2012 in Santa Fe, New Mexico.
Finished Prokaryotic Genome Assemblies from a Low-cost Combination of Short and Long Reads (Seventh Annual Sequencing, Finishing, Analysis in the Future (SFAF) Meeting 2012)
Yin, Shuangye
Shuangye Yin on "Finished prokaryotic genome assemblies from a low-cost combination of short and long reads" at the 2012 Sequencing, Finishing, Analysis in the Future Meeting held June 5-7, 2012 in Santa Fe, New Mexico.
Interoceptive accuracy and panic.
Zoellner, L A; Craske, M G
Psychophysiological models of panic hypothesize that panickers focus attention on and become anxious about the physical sensations associated with panic. Attention on internal somatic cues has been labeled interoception. The present study examined the role of physiological arousal and subjective anxiety on interoceptive accuracy. Infrequent panickers and nonanxious participants participated in an initial baseline to examine overall interoceptive accuracy. Next, participants ingested caffeine, about which they received either safety or no safety information. Using a mental heartbeat tracking paradigm, participants' count of their heartbeats during specific time intervals were coded based on polygraph measures. Infrequent panickers were more accurate in the perception of their heartbeats than nonanxious participants. Changes in physiological arousal were not associated with increased accuracy on the heartbeat perception task. However, higher levels of self-reported anxiety were associated with superior performance. PMID:10596462
Accuracy potentials for large space antenna structures
NASA Technical Reports Server (NTRS)
Hedgepeth, J. M.
The relationships among materials selection, truss design, and manufacturing techniques in the interest of surface accuracies for large space antennas are discussed. Among the antenna configurations considered are: tetrahedral truss, pretensioned truss, and geodesic dome and radial rib structures. Comparisons are made of the accuracy achievable by truss and dome structure types for a wide variety of diameters, focal lengths, and wavelength of radiated signal, taking into account such deforming influences as solar heating-caused thermal transients and thermal gradients.
Accuracy of deception judgments.
Bond, Charles F; DePaulo, Bella M
We analyze the accuracy of deception judgments, synthesizing research results from 206 documents and 24,483 judges. In relevant studies, people attempt to discriminate lies from truths in real time with no special aids or training. In these circumstances, people achieve an average of 54% correct lie-truth judgments, correctly classifying 47% of lies as deceptive and 61% of truths as nondeceptive. Relative to cross-judge differences in accuracy, mean lie-truth discrimination abilities are nontrivial, with a mean accuracy d of roughly .40. This produces an effect that is at roughly the 60th percentile in size, relative to others that have been meta-analyzed by social psychologists. Alternative indexes of lie-truth discrimination accuracy correlate highly with percentage correct, and rates of lie detection vary little from study to study. Our meta-analyses reveal that people are more accurate in judging audible than visible lies, that people appear deceptive when motivated to be believed, and that individuals regard their interaction partners as honest. We propose that people judge others' deceptions more harshly than their own and that this double standard in evaluating deceit can explain much of the accumulated literature. PMID:16859438
Studies on Application of Aroma Finish on Silk Fabric
NASA Astrophysics Data System (ADS)
Hipparagi, Sanganna Aminappa; Srinivasa, Thirumalappa; Das, Brojeswari; Naik, Subhas Venkatappa; Purushotham, Serampur Parappa
Aromatic treatments on textiles have gained importance in the recent years. In the present article work has been done on fragrance finish application on silk material. Silk is an expensive natural fibre used for apparel purpose and known for its feel and appeal. Incorporation of fragrance material in silk product, will add more value to it. Present work focuses to impart durable aroma finish for silk products to be home washed or subjected to dry cleaning. Microencapsulated aroma chemical has been used for the treatment. Impregnation method, Exhaust method, Dip-Pad-Dry method and Spray method have been used to see the influence of application method on the uptake and performance. Evaluation of the aroma treated material has been done through subjective evaluation as per Odor Intensity Reference Scaling (OIRS). Effect of the aroma finishing on the physical properties of the fabric has also been studied. No adverse effect has been observed on the stiffness of the fabric after the aroma treatment.
Method and means for producing fluorocarbon finishes on fibrous structures
NASA Technical Reports Server (NTRS)
Toy, Madeline S. (Inventor); Stringham, Roger S. (Inventor); Fogg, Lawrence C. (Inventor)
An improved process and apparatus is provided for imparting chemically bonded fluorocarbon finishes to textiles. In the process, the textiles are contacted with a gaseous mixture of fluoroolefins in an inert diluent gas in the presence of ultraviolet light under predetermined conditions.
The US Environmetal ProtectionAgenccy's Metal Finishing
Facility Risk Screening Tool (MFFRST)
William M. Barrett Jr, Ph.D. , P.E. ; Paul Harten, Ph.D.1, and Matthew Lorber
The US Environmental Protection Agency completed the development of the first version of...
Introduction to Concrete Finishing. Instructor Edition. Introduction to Construction Series.
ERIC Educational Resources Information Center
Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.
This instructor's guide contains the materials required to teach a competency-based introductory course in concrete finishing to students who have chosen to explore careers in construction. The following topics are covered in the course's three instructional units: concrete materials, concrete tools, and applied skills. Each unit contains some or…
Graphic Arts: The Press and Finishing Processes. Third Edition.
ERIC Educational Resources Information Center
Crummett, Dan
This document contains teacher and student materials for a course in graphic arts concentrating on printing presses and the finishing process for publications. Seven units of instruction cover the following topics: (1) offset press systems; (2) offset inks and dampening chemistry; (3) offset press operating procedures; (4) preventive maintenance…
Machine finishes balls to high degree of roundness
NASA Technical Reports Server (NTRS)
Angele, W.; Hill, J. P., Jr.
Machine was developed to finish ball to roundness within 12.5 nm (half a microinch) from any types of hard material. Grinding and polishing to this tolerance is accomplished by lapping elements on four to six motor-driven spindles. Spindles are adjustably spring-loaded to ensure constant contact pressure on ball and are driven by variable speed electric motors.
71. September 1913 "No. 113. Some of the finished bitulithic ...
Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey
71. September 1913 "No. 113. Some of the finished bitulithic or bituminous macadam road after being sanded and rolled, in the foreground. In the middle distance men are applying oil to incomplete section. In the far distance, roller is working on foundation course." - Crater Lake National Park Roads, Klamath Falls, Klamath County, OR
Numerous waterborne outbreaks of cryptosporidiosis have occurred with the most notable being the 1993 episode in Milwaukee. As a result, the past decade has seen a massive effort expended on the development of methods to detect Cryptosporidium parvum oocysts in source and finish...
Carpentry and Finishing Procedures. Building Maintenance. Module II. Instructor's Guide.
ERIC Educational Resources Information Center
Hawk, Sam; Brunk, Art
This curriculum guide, keyed to the building maintenance competency profile developed by industry and education professionals, provides three units on carpentry and finishing procedures. The first unit, Exterior Carpentry, contains the following lessons: carpentry safety procedures, ladder and scaffolding safety, door installation/repair,…
1. The finished hull of a 180 is launched in ...
Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey
1. The finished hull of a 180 is launched in Duluth, Minnesota. Note the men holding onto the rail and riding the vessel during its launch. - U.S. Coast Guard Buoy Tenders, 180' Class, U.S. Coast Guard Headquarters, 2100 Second Street Southwest, Washington, District of Columbia, DC
Illinois Occupational Skill Standards: Finishing and Distribution Cluster.
ERIC Educational Resources Information Center
Illinois Occupational Skill Standards and Credentialing Council, Carbondale.
This document, which is intended as a guide for work force preparation program providers, details the Illinois occupational skill standards for programs preparing students for employment in occupations in the finishing and distribution cluster. The document begins with a brief overview of the Illinois perspective on occupational skill standards…
This demonstration was performed to study the operation, performance and economics of a new sulfide precipitation process ('Sulfex'TN), for treating metal finishing wastewaters. The study was performed by Holley Carburetor Division of Colt Industries, with assistance from the Per...
Enhancement of the US Environmental Protection Agency's
Metal Finishing Facility Risk Screening Tool (MFFRST)
William M. Barrett Jr, Ph.D., P.E. , P.E.; Paul Harten, Ph.D.1, Matt Lorber , Charles Peck , and Steve Schwartz, P.E., Q.E.P.3
Recently, the US Environ...
Recently the US EPA completed the development of the first version of the Metal Finishing Facility Risk Screening Tool (MFFRST) and has made this product available to the general public. MFFRST calculates the air emissions from a metal plating line and determines the risk to bot...
Crossing the Finish Line: Completing College at America's Public Universities
ERIC Educational Resources Information Center
Bowen, William G.; Chingos, Matthew M.; McPherson, Michael S.
The United States has long been a model for accessible, affordable education, as exemplified by the country's public universities. And yet less than 60 percent of the students entering American universities today are graduating. Why is this happening, and what can be done? "Crossing the Finish Line" provides the most detailed exploration ever of…
The report gives reliable data to enable EPA to determine the need for developing control technology for air and water pollution emissions from cotton and synthetic woven fabric finishing plants. The data supplements that in an earlier state-of-the-art report on the same subject ...
Interior Finishes. Floors, Walls, Ceilings: Performance Criteria. Interim Report.
ERIC Educational Resources Information Center
State Univ. Construction Fund, Albany, NY.
A research program and the testing methods it developed are described, indicating the performance criteria of interior finishes for walls, ceilings and floors. Material exposure criteria are given with the probability of damage ratings for--(1) physical impact, (2) chemical damage, (3) biological, food and water damage. The relationship of…
Almost finished: the complete genome sequence of Mycosphaerella graminicola
Technology Transfer Automated Retrieval System (TEKTRAN)
Mycosphaerella graminicola causes septoria tritici blotch of wheat. An 8.9x shotgun sequence of bread wheat strain IPO323 was generated through the Community Sequencing Program of the U.S. Department of Energy's Joint Genome Institute (JGI), and was finished at the Stanford Human Genome Center. The ...
Finishing lambs and kids on pasture in Appalachia
Technology Transfer Automated Retrieval System (TEKTRAN)
Traditional sheep, hair sheep and meat goat industries are growing rapidly in the Appalachian Region, particularly on small farms, to help produce meats for ethnic markets. Numerous forage types and qualities are used in small ruminant finishing systems. With the expansion of non-traditional lamb ...
Reviewed herein is the waste management research and development program for the leather tanning and finishing industry. Emphasis is placed on the Environmental Protection Agency's (EPA) role, both past and present, and major developments over the past few years outside EPA, incl...
The paper gives results from EPA studies on the effect of ventilation (air changes per hour) and material loading on the emission rate for selected organics and total measured organics from three wood finishing materials (stain, polyurethane, and wax). The data are analyzed to sh...
Surface topography measurements over the 1 meter to 10 micrometer spatial period bandwidth
Takacs, P.Z.; Furenlid, K.; DeBiasse, R.A.; Church, E.L.; Army Research and Development Command, Dover, NJ )
A recently-developed long-trace surface profiling instrument (LTP) is now in operation in our laboratory measuring surface profiles on grazing incidence aspheres and also conventional optical surface. The LTP characterizes surface height profiles in a non-contact manner over spatial periods ranging from 1 meter (the maximum scan length) to 2 mm (the Nyquist period for 1 mm sampling period) and complements the range of our WYKO NCP-1000 2.5X surface roughness profiler (5 mm to 9.8 {mu}m). Using these two instruments, we can fully characterize both figure and finish of an optical surface in the same way that we normally characterize surface finish, e.g., by means of the power spectral density function in the spatial frequency domain. A great deal of information about the distribution of figure errors over various spatial frequency ranges is available from this data, which is useful for process control and predicting performance at the desired wavelength and incidence angle. In addition, the LTP is able to measure the absolute radius of curvature on long-radius optics with high precision and accuracy. Angular errors in the optical head are measured in real time by an electronic autocollimator as the head traverses the linear air bearing slide. Measurements of kilometer radius optics can be made very quickly and the data analyzed in a format that is very easy to understand. 17 refs., 10 figs.
High accuracy OMEGA timekeeping
NASA Technical Reports Server (NTRS)
Imbier, E. A.
The Smithsonian Astrophysical Observatory (SAO) operates a worldwide satellite tracking network which uses a combination of OMEGA as a frequency reference, dual timing channels, and portable clock comparisons to maintain accurate epoch time. Propagational charts from the U.S. Coast Guard OMEGA monitor program minimize diurnal and seasonal effects. Daily phase value publications of the U.S. Naval Observatory provide corrections to the field collected timing data to produce an averaged time line comprised of straight line segments called a time history file (station clock minus UTC). Depending upon clock location, reduced time data accuracies of between two and eight microseconds are typical.
Techniques for setting modes of thermal and deformation effect at combined hardening and finishing operations
NASA Astrophysics Data System (ADS)
Rakhimyanov, Kh M.; Rakhimyanov, K. Kh; Rakhimyanov, A. Kh; Kutyshkin, A. V.
This paper considers the issues of setting the modes of thermal and deformation effects in the basic schemes at combined hardening and finishing operations. On the basis of solving the thermal physical problem of material high rate heating, the parameters of a thermohardened layer were determined within the range of the investigated modes. An algorithm for setting the mode parameters of high rate heating responsible for the hardening effect at the combined processing was proposed. The analysis of the mathematical model for forming a surface microrelief at ultrasonic deformation showed that the sizes, the form of fragments and the density of a microrelief were determined by the processing kinematic parameters. An algorithm for setting the rotation speed and feeding at ultrasonic deformation according to microrelief characteristics was developed. The conditions to form a completely regular microrelief on the processed surface that represent the ratio between a single imprint diameter at the ultrasonic deformation and the processing kinematic parameters were determined. The complex of the algorithms suggested for setting the mode parameters of high rate heating and ultrasonic deformation constitutes the techniques for setting the modes of combined hardening and finishing operations.
New iron-based SiC spherical composite magnetic abrasive for magnetic abrasive finishing
NASA Astrophysics Data System (ADS)
Zhang, Guixiang; Zhao, Yugang; Zhao, Dongbiao; Zuo, Dunwen; Yin, Fengshi
SiC magnetic abrasive is used to polish surfaces of precise, complex parts which are hard, brittle and highly corrosion-resistant in magnetic abrasive finishing(MAF). Various techniques are employed to produce this magnetic abrasive, but few can meet production demands because they are usually time-consuming, complex with high cost, and the magnetic abrasives made by these techniques have irregular shape and low bonding strength that result in low processing efficiency and shorter service life. Therefore, an attempt is made by combining gas atomization and rapid solidification to fabricate a new iron-based SiC spherical composite magnetic abrasive. The experimental system to prepare this new magnetic abrasive is constructed according to the characteristics of gas atomization and rapid solidification process and the performance requirements of magnetic abrasive. The new iron-based SiC spherical composite magnetic abrasive is prepared successfully when the machining parameters and the composition proportion of the raw materials are controlled properly. Its morphology, microstructure, phase composition are characterized by scanning electron microscope(SEM) and X-ray diffraction(XRD) analysis. The MAF tests on plate of mold steel S136 are carried out without grinding lubricant to assess the finishing performance and service life of this new SiC magnetic abrasive. The surface roughness( R a) of the plate worked is rapidly reduced to 0.051 μm from an initial value of 0.372 μm within 5 min. The MAF test is carried on to find that the service life of this new SiC magnetic abrasive reaches to 155 min. The results indicate that this process presented is feasible to prepare the new SiC magnetic abrasive; and compared with previous magnetic abrasives, the new SiC spherical composite magnetic abrasive has excellent finishing performance, high processing efficiency and longer service life. The presented method to fabricate magnetic abrasive through gas atomization and rapid
Legume finishing provides beef with positive human dietary fatty acid ratios and consumer preference comparable with grain-finished beef.
Chail, A; Legako, J F; Pitcher, L R; Griggs, T C; Ward, R E; Martini, S; MacAdam, J W
Consumer liking, proximate composition, pH, Warner-Bratzler shear force, fatty acid composition, and volatile compounds were determined from the LM (longissimus thoracis) of cattle ( = 6 per diet) finished on conventional feedlot (USUGrain), legume, and grass forage diets. Forage diets included a condensed tannin-containing perennial legume, birdsfoot trefoil (; USUBFT), and a grass, meadow brome ( Rehmann; USUGrass). Moreover, representative retail forage (USDA Certified Organic Grass-fed [OrgGrass]) and conventional beef (USDA Choice, Grain-fed; ChGrain) were investigated ( = 6 per retail type). The ChGrain had the greatest ( < 0.05) intramuscular fat (IMF) percentage followed by USUGrain, the IMF percentage of which was greater ( < 0.05) than that of USUGrass and OrgGrass. The IMF content of USUBFT was similar ( > 0.05) to that of both USUGrain and USUGrass. Both grain-finished beef treatments were rated greater ( < 0.05) for flavor, tenderness, fattiness, juiciness, and overall liking compared with USUGrass and OrgGrass. Consumer liking of USUBFT beef tenderness, fattiness, and overall liking were comparable ( > 0.05) with that of USUGrain and ChGrain. Flavor liking was rated greatest ( < 0.05) for USUGrain and ChGrain, and that of USUBFT was intermediate ( > 0.05) to those of ChGrain, USUGrass, and OrgGrass. Cumulative SFA and MUFA concentrations were greatest ( < 0.05) in ChGrain and USUGrain, whereas USUGrass and OrgGrass had lower ( < 0.05) concentrations. Concentrations of cumulative SFA and MUFA in USUBFT were intermediate and similar ( > 0.05) to those of USUGrain and USUGrass. Each forage-finished beef treatment, USUGrass, OrgGrass, and USUBFT, had lower ( < 0.001) ratios of -6:-3 fatty acids. Hexanal was the most numerically abundant volatile compound. The concentration of hexanal increased with increasing concentrations of total PUFA. Among all the lipid degradation products (aldehydes, alcohols, furans, carboxylic acids, and ketones) measured in this
Measuring Tracking Accuracy of CCD Imagers
NASA Technical Reports Server (NTRS)
Stanton, R. H.; Dennison, E. W.
Tracking accuracy and resolution of charge-coupled device (CCD) imaging arrays measured by instrument originally developed for measuring performance of star-tracking telescope. Operates by projecting one or more artifical star images on surface of CCD array, moving stars in controlled patterns, and comparing star locations computed from CCD outputs with those calculated from step coordinates of micropositioner.
Immunological, physiological and behavioral effects of Salmonella enterica carriage and shedding in experimentally infected finishing pigs
Technology Transfer Automated Retrieval System (TEKTRAN)
Finishing pigs infected with Salmonella pose significant food safety risks by carrying the pathogen into abattoirs. This study was conducted to determine the dynamic of Salmonella infection in finishing pigs, and associated immunological, physiological, and behavioral alterations, by longitudinally ...
40 CFR 63.5390 - How do I measure the HAP content of a finish?
Code of Federal Regulations, 2013 CFR
... determine the HAP content of a finish, the reference method is EPA Method 311 of appendix A of 40 CFR part... (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Leather Finishing Operations...
40 CFR 63.5390 - How do I measure the HAP content of a finish?
Code of Federal Regulations, 2010 CFR
... the HAP content of a finish, the reference method is EPA Method 311 of appendix A of 40 CFR part 63... National Emission Standards for Hazardous Air Pollutants for Leather Finishing Operations Testing...
40 CFR 63.5390 - How do I measure the HAP content of a finish?
Code of Federal Regulations, 2012 CFR
... determine the HAP content of a finish, the reference method is EPA Method 311 of appendix A of 40 CFR part... (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Leather Finishing Operations...
Accuracy in Judgments of Aggressiveness
Kenny, David A.; West, Tessa V.; Cillessen, Antonius H. N.; Coie, John D.; Dodge, Kenneth A.; Hubbard, Julie A.; Schwartz, David
Perceivers are both accurate and biased in their understanding of others. Past research has distinguished between three types of accuracy: generalized accuracy, a perceiver's accuracy about how a target interacts with others in general; perceiver accuracy, a perceiver's view of others corresponding with how the perceiver is treated by others in general; and dyadic accuracy, a perceiver's accuracy about a target when interacting with that target. Researchers have proposed that there should be more dyadic than other forms of accuracy among well-acquainted individuals because of the pragmatic utility of forecasting the behavior of interaction partners. We examined behavioral aggression among well-acquainted peers. A total of 116 9-year-old boys rated how aggressive their classmates were toward other classmates. Subsequently, 11 groups of 6 boys each interacted in play groups, during which observations of aggression were made. Analyses indicated strong generalized accuracy yet little dyadic and perceiver accuracy. PMID:17575243
McDevitt, J T; Gurst, A H; Chen, Y
We attempted to determine the accuracy of manually splitting hydrochlorothiazide tablets. Ninety-four healthy volunteers each split ten 25-mg hydrochlorothiazide tablets, which were then weighed using an analytical balance. Demographics, grip and pinch strength, digit circumference, and tablet-splitting experience were documented. Subjects were also surveyed regarding their willingness to pay a premium for commercially available, lower-dose tablets. Of 1752 manually split tablet portions, 41.3% deviated from ideal weight by more than 10% and 12.4% deviated by more than 20%. Gender, age, education, and tablet-splitting experience were not predictive of variability. Most subjects (96.8%) stated a preference for commercially produced, lower-dose tablets, and 77.2% were willing to pay more for them. For drugs with steep dose-response curves or narrow therapeutic windows, the differences we recorded could be clinically relevant. PMID:9469693
Effect of Finishing System on Subcutaneous Fat Melting Point and Fatty Acid Composition
Technology Transfer Automated Retrieval System (TEKTRAN)
Angus-cross steers (n = 69) were used to determine the effect of finishing system on subcutaneous fat melting point and fatty acid composition. Three finishing systems were evaluated: 1) mixed pasture for 134 d [MP], 2) mixed pasture for 93 d and alfalfa for 41 d [AL], or 3) concentrate finishing f...
21 CFR 820.80 - Receiving, in-process, and finished device acceptance.
Code of Federal Regulations, 2010 CFR
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Receiving, in-process, and finished device...-process, and finished device acceptance. (a) General. Each manufacturer shall establish and maintain... acceptance activities. Each manufacturer shall establish and maintain procedures for finished...
40 CFR 425.40 - Applicability; description of the retan-wet finish-sides subcategory.
Code of Federal Regulations, 2010 CFR
... retan-wet finish-sides subcategory. 425.40 Section 425.40 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS LEATHER TANNING AND FINISHING POINT SOURCE CATEGORY Retan-Wet Finish-Sides Subcategory § 425.40 Applicability; description of the retan-wet...
40 CFR 63.1347 - Standards for raw and finish mills.
Code of Federal Regulations, 2010 CFR
... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Standards for raw and finish mills. 63... and Operating Limits § 63.1347 Standards for raw and finish mills. The owner or operator of each new or existing raw mill or finish mill at a facility which is a major source subject to the...
40 CFR 429.130 - Applicability; description of the finishing subcategory.
Code of Federal Regulations, 2010 CFR
... finishing subcategory. 429.130 Section 429.130 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS TIMBER PRODUCTS PROCESSING POINT SOURCE CATEGORY Finishing Subcategory § 429.130 Applicability; description of the finishing subcategory. This subpart applies...
7 CFR 58.344 - Storage of finished product in freezer.
Code of Federal Regulations, 2010 CFR
... 7 Agriculture 3 2010-01-01 2010-01-01 false Storage of finished product in freezer. 58.344 Section... Service 1 Operations and Operating Procedures § 58.344 Storage of finished product in freezer. (a) Sharp..., if necessary, at a later time. Requirements for Finished Products Bearing USDA...
46 CFR 116.422 - Ceilings, linings, trim, interior finish and decorations.
Code of Federal Regulations, 2010 CFR
... 46 Shipping 4 2010-10-01 2010-10-01 false Ceilings, linings, trim, interior finish and decorations... PASSENGERS CONSTRUCTION AND ARRANGEMENT Fire Protection § 116.422 Ceilings, linings, trim, interior finish... Commandant. (b) Bulkheads, linings and ceilings may be covered by a combustible interior finish provided...
Technology Transfer Automated Retrieval System (TEKTRAN)
Forty-seven Angus-crossbred steers were used to evaluate the effects of forage species grazed in the last 41 d of the finishing period on rib composition, color, and palatability in forage-finished beef and compared to traditional high concentrate finished. Steers grazed naturalized pastures (bluegr...
40 CFR 141.511 - What is required of new finished water reservoirs?
Code of Federal Regulations, 2013 CFR
... reservoirs? 141.511 Section 141.511 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Disinfection-Systems Serving Fewer Than 10,000 People Finished Water Reservoirs § 141.511 What is required of new finished water reservoirs? If your system begins construction of a finished water reservoir on...
40 CFR 141.510 - Is my system subject to the new finished water reservoir requirements?
Code of Federal Regulations, 2014 CFR
... finished water reservoir requirements? 141.510 Section 141.510 Protection of Environment ENVIRONMENTAL... Filtration and Disinfection-Systems Serving Fewer Than 10,000 People Finished Water Reservoirs § 141.510 Is my system subject to the new finished water reservoir requirements? All subpart H systems which...
40 CFR 141.511 - What is required of new finished water reservoirs?
Code of Federal Regulations, 2012 CFR
... reservoirs? 141.511 Section 141.511 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Disinfection-Systems Serving Fewer Than 10,000 People Finished Water Reservoirs § 141.511 What is required of new finished water reservoirs? If your system begins construction of a finished water reservoir on...
40 CFR 141.510 - Is my system subject to the new finished water reservoir requirements?
Code of Federal Regulations, 2012 CFR
... finished water reservoir requirements? 141.510 Section 141.510 Protection of Environment ENVIRONMENTAL... Filtration and Disinfection-Systems Serving Fewer Than 10,000 People Finished Water Reservoirs § 141.510 Is my system subject to the new finished water reservoir requirements? All subpart H systems which...
40 CFR 141.511 - What is required of new finished water reservoirs?
Code of Federal Regulations, 2014 CFR
... reservoirs? 141.511 Section 141.511 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Disinfection-Systems Serving Fewer Than 10,000 People Finished Water Reservoirs § 141.511 What is required of new finished water reservoirs? If your system begins construction of a finished water reservoir on...
40 CFR 141.510 - Is my system subject to the new finished water reservoir requirements?
Code of Federal Regulations, 2013 CFR
... finished water reservoir requirements? 141.510 Section 141.510 Protection of Environment ENVIRONMENTAL... Filtration and Disinfection-Systems Serving Fewer Than 10,000 People Finished Water Reservoirs § 141.510 Is my system subject to the new finished water reservoir requirements? All subpart H systems which...
Technology Transfer Automated Retrieval System (TEKTRAN)
This study aimed to examine the effects of ractopamine (RAC) on behavior and physiology of pigs during handling and transport. Twenty-four groups of 3 finishing pigs were randomly assigned to one of two treatments, four weeks prior to slaughter; 1) finishing feed plus RAC (9ppm), 2) finishing feed a...
40 CFR 410.50 - Applicability; description of the knit fabric finishing subcategory.
Code of Federal Regulations, 2011 CFR
... fabric finishing subcategory. 410.50 Section 410.50 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS TEXTILE MILLS POINT SOURCE CATEGORY Knit Fabric Finishing Subcategory § 410.50 Applicability; description of the knit fabric finishing subcategory....
40 CFR 410.40 - Applicability; description of the woven fabric finishing subcategory.
Code of Federal Regulations, 2011 CFR
... fabric finishing subcategory. 410.40 Section 410.40 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS TEXTILE MILLS POINT SOURCE CATEGORY Woven Fabric Finishing Subcategory § 410.40 Applicability; description of the woven fabric finishing subcategory....
21 CFR 181.26 - Drying oils as components of finished resins.
Code of Federal Regulations, 2013 CFR
... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Drying oils as components of finished resins. 181... Prior-Sanctioned Food Ingredients § 181.26 Drying oils as components of finished resins. Substances classified as drying oils, when migrating from food-packaging material (as components of finished...
21 CFR 181.26 - Drying oils as components of finished resins.
Code of Federal Regulations, 2012 CFR
... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Drying oils as components of finished resins. 181... Prior-Sanctioned Food Ingredients § 181.26 Drying oils as components of finished resins. Substances classified as drying oils, when migrating from food-packaging material (as components of finished...
21 CFR 820.80 - Receiving, in-process, and finished device acceptance.
Code of Federal Regulations, 2012 CFR
... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Receiving, in-process, and finished device...-process, and finished device acceptance. (a) General. Each manufacturer shall establish and maintain... acceptance activities. Each manufacturer shall establish and maintain procedures for finished...
21 CFR 820.80 - Receiving, in-process, and finished device acceptance.
Code of Federal Regulations, 2013 CFR
... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Receiving, in-process, and finished device...-process, and finished device acceptance. (a) General. Each manufacturer shall establish and maintain... acceptance activities. Each manufacturer shall establish and maintain procedures for finished...
21 CFR 820.80 - Receiving, in-process, and finished device acceptance.
Code of Federal Regulations, 2011 CFR
... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Receiving, in-process, and finished device...-process, and finished device acceptance. (a) General. Each manufacturer shall establish and maintain... acceptance activities. Each manufacturer shall establish and maintain procedures for finished...
40 CFR 427.80 - Applicability; description of the coating or finishing of asbestos textiles subcategory.
Code of Federal Regulations, 2010 CFR
... coating or finishing of asbestos textiles subcategory. 427.80 Section 427.80 Protection of Environment... SOURCE CATEGORY Coating or Finishing of Asbestos Textiles Subcategory § 427.80 Applicability; description of the coating or finishing of asbestos textiles subcategory. The provisions of this subpart...
Painting and Finishing in the Home; Construction 7-9--Prevocational: 5846.07.
ERIC Educational Resources Information Center
Dade County Public Schools, Miami, FL.
The beginning course provides students with the various techniques and supplies necessary for finishing and refinishing in the home and for home furnishings. Course content includes goals, specific objectives, orientation, selecting tools, equipment, finishes, finishing problems, and maintenance and safety. Also incorporated are consumer…
School Building Finishing and Economy. The School Building Economy Series, No. 6.
ERIC Educational Resources Information Center
Connecticut State Dept. of Education, Hartford.
Materials, elements, and methods of economical school construction are illustrated through explanatory outlines and accompany photographs and diagrams. Finishing elements covered include--(1) finished floorings, (2) ceilings and acoustical finishes, (3) carpentry and millwork, (4) chalkboards and tackboards, (5) toilet partitions, (6) finishing…
Minimizing artifact formation in magnetorheological finishing of chemical vapor deposition ZnS flats.
Kozhinova, Irina A; Romanofsky, Henry J; Maltsev, Alexander; Jacobs, Stephen D; Kordonski, William I; Gorodkin, Sergei R
The polishing performance of magnetorheological (MR) fluids prepared with a variety of magnetic and nonmagnetic ingredients was studied on four types of initial surface for chemical vapor deposition (CVD) ZnS flats from domestic and foreign sources. The results showed that it was possible to greatly improve smoothing performance of magnetorheological finishing (MRF) by altering the fluid composition, with the best results obtained for nanoalumina abrasive used with soft carbonyl iron and altered MR fluid chemistry. Surface roughness did not exceed 20 nm peak to valley and 2 nm rms after removal of 2 microm of material. The formation of orange peel and the exposure of a pebblelike structure inherent in ZnS from the CVD process were suppressed. PMID:16075880
Ultra-low roughness magneto-rheological finishing for EUV mask substrates
NASA Astrophysics Data System (ADS)
Dumas, Paul; Jenkins, Richard; McFee, Chuck; Kadaksham, Arun J.; Balachandran, Dave K.; Teki, Ranganath
EUV mask substrates, made of titania-doped fused silica, ideally require sub-Angstrom surface roughness, sub-30 nm flatness, and no bumps/pits larger than 1 nm in height/depth. To achieve the above specifications, substrates must undergo iterative global and local polishing processes. Magnetorheological finishing (MRF) is a local polishing technique which can accurately and deterministically correct substrate figure, but typically results in a higher surface roughness than the current requirements for EUV substrates. We describe a new super-fine MRF® polishing fluid whichis able to meet both flatness and roughness specifications for EUV mask blanks. This eases the burden on the subsequent global polishing process by decreasing the polishing time, and hence the defectivity and extent of figure distortion.
On-Line Mirror Surfacing Monitored by X-ray Shearing Interferometry and X-ray Scattering
Ziegler, E.; Peverini, L.; Kozhevnikov, I. V.; Weitkamp, T.; David, C.
We propose a novel fabrication scheme combining a mirror surfacing tool and an on-line metrology instrument, the latter capable of controlling both figure and finish of an X-ray mirror with an accuracy matching the challenging specifications of nanofocusing reflective optics for synchrotron and FEL X-ray beams. This approach will be complementary to the present technologies. The paper reviews some recent achievements and presents pertinent examples of on-line diagnostics performed at the ESRF BM05 beamline for which X-rays prove to be a unique probe.
The finished DNA sequence of human chromosome 12.
Scherer, Steven E; Muzny, Donna M; Buhay, Christian J; Chen, Rui; Cree, Andrew; Ding, Yan; Dugan-Rocha, Shannon; Gill, Rachel; Gunaratne, Preethi; Harris, R Alan; Hawes, Alicia C; Hernandez, Judith; Hodgson, Anne V; Hume, Jennifer; Jackson, Andrew; Khan, Ziad Mohid; Kovar-Smith, Christie; Lewis, Lora R; Lozado, Ryan J; Metzker, Michael L; Milosavljevic, Aleksandar; Miner, George R; Montgomery, Kate T; Morgan, Margaret B; Nazareth, Lynne V; Scott, Graham; Sodergren, Erica; Song, Xing-Zhi; Steffen, David; Lovering, Ruth C; Wheeler, David A; Worley, Kim C; Yuan, Yi; Zhang, Zhengdong; Adams, Charles Q; Ansari-Lari, M Ali; Ayele, Mulu; Brown, Mary J; Chen, Guan; Chen, Zhijian; Clerc-Blankenburg, Kerstin P; Davis, Clay; Delgado, Oliver; Dinh, Huyen H; Draper, Heather; Gonzalez-Garay, Manuel L; Havlak, Paul; Jackson, Laronda R; Jacob, Leni S; Kelly, Susan H; Li, Li; Li, Zhangwan; Liu, Jing; Liu, Wen; Lu, Jing; Maheshwari, Manjula; Nguyen, Bao-Viet; Okwuonu, Geoffrey O; Pasternak, Shiran; Perez, Lesette M; Plopper, Farah J H; Santibanez, Jireh; Shen, Hua; Tabor, Paul E; Verduzco, Daniel; Waldron, Lenee; Wang, Qiaoyan; Williams, Gabrielle A; Zhang, Jingkun; Zhou, Jianling; Allen, Carlana C; Amin, Anita G; Anyalebechi, Vivian; Bailey, Michael; Barbaria, Joseph A; Bimage, Kesha E; Bryant, Nathaniel P; Burch, Paula E; Burkett, Carrie E; Burrell, Kevin L; Calderon, Eliana; Cardenas, Veronica; Carter, Kelvin; Casias, Kristal; Cavazos, Iracema; Cavazos, Sandra R; Ceasar, Heather; Chacko, Joseph; Chan, Sheryl N; Chavez, Dean; Christopoulos, Constantine; Chu, Joseph; Cockrell, Raynard; Cox, Caroline D; Dang, Michelle; Dathorne, Stephanie R; David, Robert; Davis, Candi Mon'Et; Davy-Carroll, Latarsha; Deshazo, Denise R; Donlin, Jeremy E; D'Souza, Lisa; Eaves, Kristy A; Egan, Amy; Emery-Cohen, Alexandra J; Escotto, Michael; Flagg, Nicole; Forbes, Lisa D; Gabisi, Abdul M; Garza, Melissa; Hamilton, Cerissa; Henderson, Nicholas; Hernandez, Omar; Hines, Sandra; Hogues, Marilyn E; Huang, Mei; Idlebird, DeVincent G; Johnson, Rudy; Jolivet, Angela; Jones, Sally; Kagan, Ryan; King, Laquisha M; Leal, Belita; Lebow, Heather; Lee, Sandra; LeVan, Jaclyn M; Lewis, Lakeshia C; London, Pamela; Lorensuhewa, Lorna M; Loulseged, Hermela; Lovett, Demetria A; Lucier, Alice; Lucier, Raymond L; Ma, Jie; Madu, Renita C; Mapua, Patricia; Martindale, Ashley D; Martinez, Evangelina; Massey, Elizabeth; Mawhiney, Samantha; Meador, Michael G; Mendez, Sylvia; Mercado, Christian; Mercado, Iracema C; Merritt, Christina E; Miner, Zachary L; Minja, Emmanuel; Mitchell, Teresa; Mohabbat, Farida; Mohabbat, Khatera; Montgomery, Baize; Moore, Niki; Morris, Sidney; Munidasa, Mala; Ngo, Robin N; Nguyen, Ngoc B; Nickerson, Elizabeth; Nwaokelemeh, Ogechi O; Nwokenkwo, Stanley; Obregon, Melissa; Oguh, Maryann; Oragunye, Njideka; Oviedo, Rodolfo J; Parish, Bridgette J; Parker, David N; Parrish, Julia; Parks, Kenya L; Paul, Heidie A; Payton, Brett A; Perez, Agapito; Perrin, William; Pickens, Adam; Primus, Eltrick L; Pu, Ling-Ling; Puazo, Maria; Quiles, Miyo M; Quiroz, Juana B; Rabata, Dina; Reeves, Kacy; Ruiz, San Juana; Shao, Hongmei; Sisson, Ida; Sonaike, Titilola; Sorelle, Richard P; Sutton, Angelica E; Svatek, Amanda F; Svetz, Leah Anne; Tamerisa, Kavitha S; Taylor, Tineace R; Teague, Brian; Thomas, Nicole; Thorn, Rachel D; Trejos, Zulma Y; Trevino, Brenda K; Ukegbu, Ogechi N; Urban, Jeremy B; Vasquez, Lydia I; Vera, Virginia A; Villasana, Donna M; Wang, Ling; Ward-Moore, Stephanie; Warren, James T; Wei, Xuehong; White, Flower; Williamson, Angela L; Wleczyk, Regina; Wooden, Hailey S; Wooden, Steven H; Yen, Jennifer; Yoon, Lillienne; Yoon, Vivienne; Zorrilla, Sara E; Nelson, David; Kucherlapati, Raju; Weinstock, George; Gibbs, Richard A
Human chromosome 12 contains more than 1,400 coding genes and 487 loci that have been directly implicated in human disease. The q arm of chromosome 12 contains one of the largest blocks of linkage disequilibrium found in the human genome. Here we present the finished sequence of human chromosome 12, which has been finished to high quality and spans approximately 132 megabases, representing approximately 4.5% of the human genome. Alignment of the human chromosome 12 sequence across vertebrates reveals the origin of individual segments in chicken, and a unique history of rearrangement through rodent and primate lineages. The rate of base substitutions in recent evolutionary history shows an overall slowing in hominids compared with primates and rodents. PMID:16541075
26. A battery of calender presses at work finishing magazine ...
Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey
26. A battery of calender presses at work finishing magazine paper. After the coated paper has been dried and put into rolls, as shown in the preceding pictures, it is brought to the room shown here. A roll is put in the reel at the man's shoulder in the foreground and started through the machine. It passes between the two top rollers and then in and out between the succeeding rollers, until it reaches the bottom. Many tons' pressure have ironed it before it comes out and is rolled up again. This process gives it the finish that the National Geographic must have to maintain its high standard. (p.240.) - Champion-International Paper Company, West bank of Spicket River at Canal Street, Lawrence, Essex County, MA
Method and system for processing optical elements using magnetorheological finishing
Menapace, Joseph Arthur; Schaffers, Kathleen Irene; Bayramian, Andrew James; Molander, William A
A method of finishing an optical element includes mounting the optical element in an optical mount having a plurality of fiducials overlapping with the optical element and obtaining a first metrology map for the optical element and the plurality of fiducials. The method also includes obtaining a second metrology map for the optical element without the plurality of fiducials, forming a difference map between the first metrology map and the second metrology map, and aligning the first metrology map and the second metrology map. The method further includes placing mathematical fiducials onto the second metrology map using the difference map to form a third metrology map and associating the third metrology map to the optical element. Moreover, the method includes mounting the optical element in the fixture in an MRF tool, positioning the optical element in the fixture; removing the plurality of fiducials, and finishing the optical element.
Farmer and Public Attitudes Toward Lamb Finishing Systems.
Coleman, Grahame; Jongman, Ellen; Greenfield, L; Hemsworth, Paul
To develop research and policy on the welfare of lambs in intensive finishing systems, it is important to understand public and sheep farmers' attitudes. The aim of this research was to identify and compare farmer and community attitudes relevant to the intensification of lamb finishing. The majority of respondents in the community sample expressed concern about all listed welfare issues, but particularly about feedlotting of lambs and the associated confinement. These attitudes correlated with community views on the importance of welfare issues including social contact and freedom to roam. Farmers expressed much lower levels of concern than did the general public except with regard to the health of lambs, disease control, access to shade, and lack of access to clean water. PMID:26882113

subset: commoncrawl