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Piping benchmark problems for the ABB/CE System 80+ Standardized Plant
Bezler, P.; DeGrassi, G.; Braverman, J.; Wang, Y.K. [Brookhaven National Lab., Upton, NY (United States)] [Brookhaven National Lab., Upton, NY (United States)
To satisfy the need for verification of the computer programs and modeling techniques that will be used to perform the final piping analyses for the ABB/Combustion Engineering System 80+ Standardized Plant, three benchmark problems were developed. The problems are representative piping systems subjected to representative dynamic loads with solutions developed using the methods being proposed for analysis for the System 80+ standard design. It will be required that the combined license licensees demonstrate that their solution to these problems are in agreement with the benchmark problem set. The first System 80+ piping benchmark is a uniform support motion response spectrum solution for one section of the feedwater piping subjected to safe shutdown seismic loads. The second System 80+ piping benchmark is a time history solution for the feedwater piping subjected to the transient loading induced by a water hammer. The third System 80+ piping benchmark is a time history solution of the pressurizer surge line subjected to the accelerations induced by a main steam line pipe break. The System 80+ reactor is an advanced PWR type.
Piping benchmark problems. Volume 1. Dynamic analysis uniform support motion response spectrum method
Bezler, P.; Hartzman, M.; Reich, M.
A set of benchmark problems and solutions have been developed for verifying the adequacy of computer programs used for dynamic analysis and design of nuclear piping systems by the Response Spectrum Method. The problems range from simple to complex configurations which are assumed to experience linear elastic behavior. The dynamic loading is represented by uniform support motion, assumed to be induced by seismic excitation in three spatial directions. The solutions consist of frequencies, participation factors, nodal displacement components and internal force and moment components. Solutions to associated anchor point motion static problems are not included.
Piping systems physical benchmarks
Bezler, P.; Subudhi, M.
Physical benchmark evaluations are used to assess the accuracy and adequacy of the analysis methods and assumptions used in typical piping qualification evaluations. To date physical benchmark evaluations have been completed for five systems involving both laboratory tested and in situ piping. In each evaluation elastic finite element methods are used to predict the time history response of a system for which physical test results are available. In the analytical simulations the measured support excitations and the measured damping properties are used as input and the acceleration and displacement response of piping interior points are predicted as output. Most evaluations were performed blind in that only the measured inputs are provided at the time of analysis. A summary of the overall results as well as predicted and measured time history traces for selected points are included.
Benchmark problems and solutions
NASA Technical Reports Server (NTRS)
Tam, Christopher K. W.
The scientific committee, after careful consideration, adopted six categories of benchmark problems for the workshop. These problems do not cover all the important computational issues relevant to Computational Aeroacoustics (CAA). The deciding factor to limit the number of categories to six was the amount of effort needed to solve these problems. For reference purpose, the benchmark problems are provided here. They are followed by the exact or approximate analytical solutions. At present, an exact solution for the Category 6 problem is not available.
Eddy Current Benchmark Problem
NASA Astrophysics Data System (ADS)
Chady, T.; Sikora, R.
This paper describes the proposal of a benchmark activity. The objective of the proposed eddy current benchmark problem is to evaluate accuracy of various numerical or semi-analytical methods in predicting an eddy current probe multi-frequency response. The probe has a complicated structure and it consists of a cylindrical ferrite core with five symmetrically placed columns. The probe was used to test plates made from nickel-base superalloy INCONEL 600. In the plate a set of defects were introduced. An AC currents consist of 15 harmonic components are applied to the excitation coils. In all cases the specimens were examined by placing the probe on the reverse side of the flaws. The acquired data will be send by email to all participants of the benchmark's activity.
Experimental benchmark for piping system dynamic-response analyses
Not Available
This paper describes the scope and status of a piping system dynamics test program. A 0.20 m(8 in.) nominal diameter test piping specimen is designed to be representative of main heat transport system piping of LMFBR plants. Particular attention is given to representing piping restraints. Applied loadings consider component-induced vibration as well as seismic excitation. The principal objective of the program is to provide a benchmark for verification of piping design methods by correlation of predicted and measured responses. Pre-test analysis results and correlation methods are discussed.
Computational evaluation of two reactor benchmark problems
Cowan, James Anthony
macroscopic cross sections for various pincell models in each benchmark problem. DEF3D, a multigroup multidimensional diffusion code, was used to evaluate the uranium-fueled lattice benchmark problem of the American Nuclear Society. TWODANT, a multigroup, two...
A micro-accelerometer MDO benchmark problem
S. Tosserams; L. F. P. Etman; J. E. Rooda
Many optimization and coordination methods for multidisciplinary design optimization (MDO) have been proposed in the last\\u000a three decades. Suitable MDO benchmark problems for testing and comparing these methods are few however. This article presents\\u000a a new MDO benchmark problem based on the design optimization of an ADXL150 type lateral capacitive micro-accelerometer. The\\u000a behavioral models describe structural and dynamic effects, as
Experimental benchmark for casting problems
T. A. Kowalewski; A. Cybulski; T. Michalek
The problem motivating the current work is a mould filling during casting process. The aim of our analysis is to provide a simple experimental model simulating the main flow characteristics accompanying such process. Hence, the hot fluid is supplied under high pressure into an inclined box. Fluid flows inside the box between two cold isothermal walls, passing obstacles simulating internal
PI-ping - Benchmark Tool for Testing Latencies and Throughput in Operating Systems
NASA Astrophysics Data System (ADS)
Abaffy, J.; Kraj?ovi?, T.
In this paper we present a benchmark tool called PI-ping that can be used to compare real-time performance of operating systems. It uses two types of processes that are common in operating systems - interactive tasks demanding low latencies and also processes demanding high CPU utilization. Most operating systems have to perform well in both conditions and the goal is to achieve the highest throughput when keeping the latencies within a reasonable interval. PI-ping measures the latencies of an interactive process when the system is under heavy computational load. Using PI-ping benchmark tool we are able to compare different operating systems and we attest the functionality of it using two very common operating systems - Linux and FreeBSD.
Benchmark Control Problems for Seismically Excited Nonlinear Buildings
Y. Ohtori; R. E. Christenson; B. F. Spencer; S. J. Dyke
This paper presents an overview of the benchmark control problems for seismically excited nonlinear buildings. The goal of this study is to provide a clear basis to evaluate the efficacy of various structural control strategies. Three typical steel structures, 3-, 9- and 20-story buildings designed for the SAC project for the Los Angeles, California region, are offered as benchmark buildings.
A 3D stylized half-core CANDU benchmark problem
Justin M. Pounders; Farzad Rahnema; Dumitru Serghiuta; John Tholammakkil
A 3D stylized half-core Canadian deuterium uranium (CANDU) reactor benchmark problem is presented. The benchmark problem is comprised of a heterogeneous lattice of 37-element natural uranium fuel bundles, heavy water moderated, heavy water cooled, with adjuster rods included as reactivity control devices. Furthermore, a 2-group macroscopic cross section library has been developed for the problem to increase the utility of
The Two Tank Experiment: A Benchmark Control Problem
Roy S. Smith; John Doyle
This paper describes an experimental process control system under development at Caltech. It is intended to be a source of benchmark control and identification problems. A first principles theoretical model is developed and compared to preliminary experimental data.
Simplified two and three dimensional HTTR benchmark problems
Zhan Zhang; Dingkang Zhang; Justin M. Pounders; Abderrafi M. Ougouag
To assess the accuracy of diffusion or transport methods for reactor calculations, it is desirable to create heterogeneous benchmark problems that are typical of whole core configurations. In this paper we have created two and three dimensional numerical benchmark problems typical of high temperature gas cooled prismatic cores. Additionally, a single cell and single block benchmark problems are also included. These problems were derived from the HTTR start-up experiment. Since the primary utility of the benchmark problems is in code-to-code verification, minor details regarding geometry and material specification of the original experiment have been simplified while retaining the heterogeneity and the major physics properties of the core from a neutronics viewpoint. A six-group material (macroscopic) cross section library has been generated for the benchmark problems using the lattice depletion code HELIOS. Using this library, Monte Carlo solutions are presented for three configurations (all-rods-in, partially-controlled and all-rods-out) for both the 2D and 3D problems. These solutions include the core eigenvalues, the block (assembly) averaged fission densities, local peaking factors, the absorption densities in the burnable poison and control rods, and pin fission density distribution for selected blocks. Also included are the solutions for the single cell and single block problems.
MFL Benchmark Problem 2: Laboratory Measurements
NASA Astrophysics Data System (ADS)
Etcheverry, J.; Pignotti, A.; S�nchez, G.; Stickar, P.
This experiment involves the measurement of the magnetic flux leaked from a rotating seamless steel tube with two machined notches. The signal measured is the radial component of the leaked field at a fixed point in space, as a function of the notch position, for four values of the liftoff and two notches. As the pipe tangential velocity was varied between 0.23 and 0.62 m/s, the sole observed effect was that of increasing the signal by a value that grows linearly with the velocity and is independent of the notch angular position.
Benchmarking transport solvers for fracture flow problems
NASA Astrophysics Data System (ADS)
Olkiewicz, Piotr; Dabrowski, Marcin
Fracture flow may dominate in rocks with low porosity and it can accompany both industrial and natural processes. Typical examples of such processes are natural flows in crystalline rocks and industrial flows in geothermal systems or hydraulic fracturing. Fracture flow provides an important mechanism for transporting mass and energy. For example, geothermal energy is primarily transported by the flow of the heated water or steam rather than by the thermal diffusion. The geometry of the fracture network and the distribution of the mean apertures of individual fractures are the key parameters with regard to the fracture network transmissivity. Transport in fractures can occur through the combination of advection and diffusion processes like in the case of dissolved chemical components. The local distribution of the fracture aperture may play an important role for both flow and transport processes. In this work, we benchmark various numerical solvers for flow and transport processes in a single fracture in 2D and 3D. Fracture aperture distributions are generated by a number of synthetic methods. We examine a single-phase flow of an incompressible viscous Newtonian fluid in the low Reynolds number limit. Periodic boundary conditions are used and a pressure difference is imposed in the background. The velocity field is primarly found using the Stokes equations. We systematically compare the obtained velocity field to the results obtained by solving the Reynolds equation. This allows us to examine the impact of the aperture distribution on the permeability of the medium and the local velocity distribution for two different mathematical descriptions of the fracture flow. Furthermore, we analyse the impact of aperture distribution on the front characteristics such as the standard deviation and the fractal dimension for systems in 2D and 3D.
Quadratic stabilization and tracking - Applications to the benchmark problem
NASA Technical Reports Server (NTRS)
Schmitendorf, W. E.; Dolphus, R. M.; Benson, R. W.
Recent results regarding quadratic stabilization and disturbance attenuation are applied to the benchmark problem. The authors investigate the minimum achievable levels of disturbance attenuation for different disturbance inputs and controlled outputs. They then design a feedforward tracking controller which tracks step inputs while maintaining the disturbance attenuation properties of the regulator.
Summary of Benchmark Control Problems for Seismically Excited Nonlinear Buildings
Y. Ohtori; R. E. Christenson; B. F. Spencer
This paper summarizes benchmark control problems for seismically excited nonlinear build- ings. Focusing on three typical steel structures, 3-, 9- and 20-story buildings designed for the SAC project for the Los Angeles, California region, the goal of this study is to provide a clear basis to evaluate the efficacy of various structural control strategies. Evaluation criteria are presented for the
Benchmark problems in which equality plays the major role
Lusk, E.; Wos, L.
We have recently heard rumors that researchers are again studying paramodulation (Wos87) in the context of strategy for its control. In part to facilitate such research, and in part to provide test problems for evaluating other approaches to equality-oriented reasoning, we offer in this article a set of benchmark problems in which equality plays the dominant role. The test problems are taken from group theory, Robbins algebra, combinatory logic, and other areas. For each problem, we include appropriate clauses and comment as to its status with regard to provability by an unaided automated reasoning program.
Benchmark problems in which equality plays the major role
Lusk, E.; Wos, L.
We have recently heard rumors that researchers are again studying paramodulation [Wos87] in the context of strategy for its control. In part to facilitate such research, and in part to provide test problems for evaluating other approaches to equality-oriented reasoning, we offer in this article a set of benchmark problems in which equality plays the dominant role. The test problems are taken from group theory, Robbins algebra, combinatory logic, and other areas. For each problem, we include appropriate clauses and comment as to its status with regard to provability by an unaided automated reasoning program.
Fourth Computational Aeroacoustics (CAA) Workshop on Benchmark Problems
NASA Technical Reports Server (NTRS)
Dahl, Milo D. (Editor)
This publication contains the proceedings of the Fourth Computational Aeroacoustics (CAA) Workshop on Benchmark Problems. In this workshop, as in previous workshops, the problems were devised to gauge the technological advancement of computational techniques to calculate all aspects of sound generation and propagation in air directly from the fundamental governing equations. A variety of benchmark problems have been previously solved ranging from simple geometries with idealized acoustic conditions to test the accuracy and effectiveness of computational algorithms and numerical boundary conditions; to sound radiation from a duct; to gust interaction with a cascade of airfoils; to the sound generated by a separating, turbulent viscous flow. By solving these and similar problems, workshop participants have shown the technical progress from the basic challenges to accurate CAA calculations to the solution of CAA problems of increasing complexity and difficulty. The fourth CAA workshop emphasized the application of CAA methods to the solution of realistic problems. The workshop was held at the Ohio Aerospace Institute in Cleveland, Ohio, on October 20 to 22, 2003. At that time, workshop participants presented their solutions to problems in one or more of five categories. Their solutions are presented in this proceedings along with the comparisons of their solutions to the benchmark solutions or experimental data. The five categories for the benchmark problems were as follows: Category 1:Basic Methods. The numerical computation of sound is affected by, among other issues, the choice of grid used and by the boundary conditions. Category 2:Complex Geometry. The ability to compute the sound in the presence of complex geometric surfaces is important in practical applications of CAA. Category 3:Sound Generation by Interacting With a Gust. The practical application of CAA for computing noise generated by turbomachinery involves the modeling of the noise source mechanism as a vortical gust interacting with an airfoil. Category 4:Sound Transmission and Radiation. Category 5:Sound Generation in Viscous Problems. Sound is generated under certain conditions by a viscous flow as the flow passes an object or a cavity.
The rotating movement of three immiscible fluids - A benchmark problem
Bakker, M.; Oude, Essink G.H.P.; Langevin, C.D.
A benchmark problem involving the rotating movement of three immiscible fluids is proposed for verifying the density-dependent flow component of groundwater flow codes. The problem consists of a two-dimensional strip in the vertical plane filled with three fluids of different densities separated by interfaces. Initially, the interfaces between the fluids make a 45??angle with the horizontal. Over time, the fluids rotate to the stable position whereby the interfaces are horizontal; all flow is caused by density differences. Two cases of the problem are presented, one resulting in a symmetric flow field and one resulting in an asymmetric flow field. An exact analytical solution for the initial flow field is presented by application of the vortex theory and complex variables. Numerical results are obtained using three variable-density groundwater flow codes (SWI, MOCDENS3D, and SEAWAT). Initial horizontal velocities of the interfaces, as simulated by the three codes, compare well with the exact solution. The three codes are used to simulate the positions of the interfaces at two times; the three codes produce nearly identical results. The agreement between the results is evidence that the specific rotational behavior predicted by the models is correct. It also shows that the proposed problem may be used to benchmark variable-density codes. It is concluded that the three models can be used to model accurately the movement of interfaces between immiscible fluids, and have little or no numerical dispersion. ?? 2003 Elsevier B.V. All rights reserved.
Xu, J.; Degrassi, G.; Chokshi, N.
Under the auspices of the US Nuclear Regulatory Commission (NRC), Brookhaven National Laboratory (BNL) developed a comprehensive program to evaluate state-of-the-art methods and computer programs for seismic analysis of typical coupled nuclear power plant (NPP) systems with nonclassical damping. In this program, four benchmark models of coupled building-piping/equipment systems with different damping characteristics were analyzed for a suite of earthquakes by program participants applying their uniquely developed methods and computer programs. This paper presents the results of their analyses, and their comparison to the benchmark solutions generated by BNL using time domain direct integration methods. The participant's analysis results established using complex modal time history methods showed good comparison with the BNL solutions, while the analyses produced with either complex-mode response spectrum methods or classical normal-mode response spectrum method, in general, produced more conservative results, when averaged over a suite of earthquakes. However, when coupling due to damping is significant, complex-mode response spectrum methods performed better than the classical normal-mode response spectrum method. Furthermore, as part of the program objectives, a parametric assessment is also presented in this paper, aimed at evaluation of the applicability of various analysis methods to problems with different dynamic characteristics unique to coupled NPP systems. It is believed that the findings and insights learned from this program will be useful in developing new acceptance criteria and providing guidance for future regulatory activities involving licensing applications of these alternate methods to coupled systems.
Identification of significant problems related to light water reactor piping systems
Work on the project was divided into three tasks. In Task 1, past surveys of LWR piping system problems and recent Licensee Event Report summaries are studied to identify the significant problems of LWR piping systems and the primary causes of these problems. Pipe cracking is identified as the most recurring problem and is mainly due to the vibration of pipes due to operating pump-pipe resonance, fluid-flow fluctuations, and vibration of pipe supports. Research relevant to the identified piping system problems is evaluated. Task 2 studies identify typical LWR piping systems and the current loads and load combinations used in the design of these systems. Definitions of loads are reviewed. In Task 3, a comparative study is carried out on the use of nonlinear analysis methods in the design of LWR piping systems. The study concludes that the current linear-elastic methods of analysis may not predict accurately the behavior of piping systems under seismic loads and may, under certain circumstances, result in nonconservative designs. Gaps at piping supports are found to have a significant effect on the response of the piping systems.
Structural control benchmark problem: Phase II-Nonlinear smart base-isolated building subjected to near-fault earthquakes
Satish Nagarajaiah; Sriram Narasimhan; Erik Johnson
SUMMARY Many branches of engineering, mathematics, and sciences, have relied on benchmark problems as a standard means to compare different solution techniques. Since 1996, the ASCE Structural Control and Monitoring Committee and Task Group on Benchmark Problems, the U.S. Panel on structural control, and IASCM have developed a series of benchmark control problems that offer a set of carefully modeled
Single pin BWR benchmark problem for coupled Monte Carlo - Thermal hydraulics analysis
Ivanov, A.; Sanchez, V. [Karlsruhe Inst. of Technology, Inst. for Neutron Physics and Reactor Technology, Herman-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Hoogenboom, J. E. [Delft Univ. of Technology, Faculty of Applied Sciences, Mekelweg 15, 2629 JB Delft (Netherlands)
As part of the European NURISP research project, a single pin BWR benchmark problem was defined. The aim of this initiative is to test the coupling strategies between Monte Carlo and subchannel codes developed by different project participants. In this paper the results obtained by the Delft Univ. of Technology and Karlsruhe Inst. of Technology will be presented. The benchmark problem was simulated with the following coupled codes: TRIPOLI-SUBCHANFLOW, MCNP-FLICA, MCNP-SUBCHANFLOW, and KENO-SUBCHANFLOW. (authors)
Total's solution to deep water pipe line problems
Not Available
The J-curve pipe laying method, developed by TOTAL C.F.P., has now completed 2,400 full scale dry tests at ACB in Nantes, France. The tests were entirely successful. The main features of the system make it possible to lay pipe in water depths ranging to 3,000 m (9,840 ft) from a dynamically positioned drillship or vessel. By conventional techniques, the limitation is 600 m (about 2,000 ft). The electron beam welding chamber can weld 24 in. piping with a wall thickness of 1.25 in. in three minutes. Ordinarily, welding on the same size pipe would take from one to two hours. With the ''J'' curve laying method the pipe is lowered almost vertically into the water and therefore has no stinger. This prevents stressing the pipes and equipment.
Benchmarking Strategies for Measuring the Quality of Healthcare: Problems and Prospects
Lovaglio, Pietro Giorgio
Over the last few years, increasing attention has been directed toward the problems inherent to measuring the quality of healthcare and implementing benchmarking strategies. Besides offering accreditation and certification processes, recent approaches measure the performance of healthcare institutions in order to evaluate their effectiveness, defined as the capacity to provide treatment that modifies and improves the patient's state of health. This paper, dealing with hospital effectiveness, focuses on research methods for effectiveness analyses within a strategy comparing different healthcare institutions. The paper, after having introduced readers to the principle debates on benchmarking strategies, which depend on the perspective and type of indicators used, focuses on the methodological problems related to performing consistent benchmarking analyses. Particularly, statistical methods suitable for controlling case-mix, analyzing aggregate data, rare events, and continuous outcomes measured with error are examined. Specific challenges of benchmarking strategies, such as the risk of risk adjustment (case-mix fallacy, underreporting, risk of comparing noncomparable hospitals), selection bias, and possible strategies for the development of consistent benchmarking analyses, are discussed. Finally, to demonstrate the feasibility of the illustrated benchmarking strategies, an application focused on determining regional benchmarks for patient satisfaction (using 2009 Lombardy Region Patient Satisfaction Questionnaire) is proposed. PMID:22666140
Semi-analytical solution to the 2014 eddy current benchmark problem
NASA Astrophysics Data System (ADS)
Miorelli, Roberto; Reboud, Christophe; Voulgaraki, Charitini; Poulakis, Nikolaos; Theodoulidis, Theodoros
This work proposes a solution to the 2014 eddy current testing benchmark, published by the WFNDEC and proposed by the authors. The aim of this benchmark is to provide reference data for eddy current testing configurations involving magnetic sensors -here Hall sensors- as receivers, as they present some advantages in terms of resolution and sensitivity. After a presentation of the benchmark cases, the theoretical approach used to solve the equivalent electromagnetic problem is detailed and a alternative computation of eddy current signals is proposed. Then, simulations are quantitatively compared to experimental data in each case and the results are discussed.
Large Core Code Evaluation Working Group Benchmark Problem Four: neutronics and burnup analysis of a large heterogeneous fast reactor. Part 1. Analysis of benchmark results. [LMFBR
C. L. Cowan; R. Protsik; J. W. Lewellen
The Large Core Code Evaluation Working Group Benchmark Problem Four was specified to provide a stringent test of the current methods which are used in the nuclear design and analyses process. The benchmark specifications provided a base for performing detailed burnup calculations over the first two irradiation cycles for a large heterogeneous fast reactor. Particular emphasis was placed on the
CMA-ES with Restarts for Solving CEC 2013 Benchmark Problems
Paris-Sud XI, Universit� de
CMA-ES with Restarts for Solving CEC 2013 Benchmark Problems Ilya Loshchilov Laboratory Strategy (CMA- ES) with restarts on a set of 28 noiseless optimization problems (including 23 multi validation of the restart strategies shows that: i). the versions of CMA-ES with weighted active covariance
Clad piping - a novel approach for solving nuclear plant service water and erosion-corrosion problems
Chakravarti, B. [NUTECH Engineers, Inc., Westmont, IL (United States)
This paper discusses the application of clad piping components to solve various nuclear plant corrosion problems, such as service water system corrosion and feedwater/condensate/steam erosion-corrosion. This approach uses a carbon steel piping component which has a metallurgically bonded alloy cladding on the ID. Different alloys are available as cladding, from stainless steels to Inconel 625, so that a specific alloy can be selected based on the service requirements. Clad piping components represent a novel approach, as they provide a mechanism to utilize resistant alloys to solve corrosion problems without affecting the plant design. Clad piping products are designed such that the carbon steel backing acts as the pressure boundary and the cladding the corrosion allowance. By selecting the proper carbon steel backing, the clad product can be engineered to allow {open_quotes}like-for-like{close_quotes} component replacement. The wall thickness, weight and stiffness of the piping would remain essentially the same. The thermal expansion coefficient of the bulk piping also remains the same. Thus, the piping design and layout is wholly unaffected, with no structural reanalysis being required. This paper discusses two applications where clad piping products are being applied for solving nuclear power plant corrosion problems. The first is in solving steam/condensate/feedwater erosion-corrosion. The second application is the utilization of Inconel 625 clad piping products for solving service water system corrosion. Clad piping products solve these problems while improving plant operation and performance by basically providing the benefits of the alloy without any of the accompanying disadvantages of redesign.
Least-Squares Spectral Element Solutions to the CAA Workshop Benchmark Problems
NASA Technical Reports Server (NTRS)
Lin, Wen H.; Chan, Daniel C.
This paper presents computed results for some of the CAA benchmark problems via the acoustic solver developed at Rocketdyne CFD Technology Center under the corporate agreement between Boeing North American, Inc. and NASA for the Aerospace Industry Technology Program. The calculations are considered as benchmark testing of the functionality, accuracy, and performance of the solver. Results of these computations demonstrate that the solver is capable of solving the propagation of aeroacoustic signals. Testing of sound generation and on more realistic problems is now pursued for the industrial applications of this solver. Numerical calculations were performed for the second problem of Category 1 of the current workshop problems for an acoustic pulse scattered from a rigid circular cylinder, and for two of the first CAA workshop problems, i. e., the first problem of Category 1 for the propagation of a linear wave and the first problem of Category 4 for an acoustic pulse reflected from a rigid wall in a uniform flow of Mach 0.5. The aim for including the last two problems in this workshop is to test the effectiveness of some boundary conditions set up in the solver. Numerical results of the last two benchmark problems have been compared with their corresponding exact solutions and the comparisons are excellent. This demonstrates the high fidelity of the solver in handling wave propagation problems. This feature lends the method quite attractive in developing a computational acoustic solver for calculating the aero/hydrodynamic noise in a violent flow environment.
Evaluation of a High-Accuracy MacCormack-Type Scheme Using Benchmark Problems
NASA Technical Reports Server (NTRS)
Hixon, R.
Due to their inherent dissipation and stability, the MacCormack scheme and its variants have been widely used in the computation of unsteady flow and acoustic problems. However, these schemes require many points per wavelength in order to propagate waves with a reasonable amount of accuracy. In this work, the linear wave propagation characteristics of MacCormack-type schemes are shown by solving several of the CAA Benchmark Problems.
Evaluation of a consistent point-kinetics model for the TMI-1 MSLB benchmark problem
Taiwo, T.A.; Dunn, F.E.; Cahalan, J.E. [Argonne National Lab., IL (United States)
The SAS-DIF3DK coupled code system is currently being used for analyzing the Three Mile Island Unit 1 (TMI-1) main-steam-line-break (MSLB) benchmark problem sponsored by the Organization for Economic Cooperation and Development Nuclear Energy Agency, the US Nuclear Regulatory Commission, and the Pennsylvania State University. The code uses the DIF3D-K spatial kinetics module for calculating the detailed core power evolution during the transient. The current analysis of the benchmark problem focuses on exercise 2, in which performance of three-dimensional, coupled neutronic/thermal-hydraulic codes is being evaluated. For this exercise, thermal-hydraulic boundary conditions are prescribed. Other exercises are defined to model the whole reactor system using point kinetics (exercise 1) and multidimensional kinetics (exercise 3) for calculating the power evolution. These exercises are useful for evaluating the accuracy of the point-kinetics schemes currently used in the nuclear industry for analyzing such transient scenarios.
PARTISN results for the C5G7 MOX benchmark problems
Dahl, J. A. (Jon A.); Alcouffe, Raymond E.
In early 2001 the Nuclear Energy Agency solicited participants for a proposed new benchmark. The benchmark, known as C5G7 MOX, is intended to be a basis to measure current transport code abilities in the treatment of reactor core problems without spatial homogenization. We have participated with the code transport code PARTISN. PARTISN (PARallel TIme Dependent SN), PARTISN solves the linear Boltzmann transport equation in static and time dependent forms on one, two and three dimensional orthogonal grids using the deterministic (SN) method. A variety of spatial discritization methods are incorporated into PARTISN, however all calculations performed here used the diamond difference approach, coupled with a volume fraction method for non-Cartesian problem geometries. Acceleration of the source iterations is accomplished with diffusion synthetic acceleration (DSA).
Trajectory Tracking by TP Model Transformation: Case Study of a Benchmark Problem
Zoltan Petres; Peter Baranyi; Peter Korondi; Hideki Hashimoto
The main objective of this paper is to study the recently proposed tensor-product-distributed-compensation (TPDC)-based control design framework in the case of tracking control design of a benchmark problem. The TPDC is a combination of the tensor product model transformation and the parallel distributed compensation framework. In this paper, we investigate the effectiveness of the TPDC design. We study how it
MC21 analysis of the nuclear energy agency Monte Carlo performance benchmark problem
Kelly, D. J.; Sutton, T. M. [Knolls Atomic Power Laboratory, Bechtel Marine Propulsion Corporation, P. O. Box 1072, Schenectady, NY 12301-1072 (United States); Wilson, S. C. [Bertis Atomic Power Laboratory, Bechtel Marine Propulsion Corporation, P. O. Box 79, West Mifflin, PA 15122-0079 (United States)
Due to the steadily decreasing cost and wider availability of large scale computing platforms, there is growing interest in the prospects for the use of Monte Carlo for reactor design calculations that are currently performed using few-group diffusion theory or other low-order methods. To facilitate the monitoring of the progress being made toward the goal of practical full-core reactor design calculations using Monte Carlo, a performance benchmark has been developed and made available through the Nuclear Energy Agency. A first analysis of this benchmark using the MC21 Monte Carlo code was reported on in 2010, and several practical difficulties were highlighted. In this paper, a newer version of MC21 that addresses some of these difficulties has been applied to the benchmark. In particular, the confidence-interval-determination method has been improved to eliminate source correlation bias, and a fission-source-weighting method has been implemented to provide a more uniform distribution of statistical uncertainties. In addition, the Forward-Weighted, Consistent-Adjoint-Driven Importance Sampling methodology has been applied to the benchmark problem. Results of several analyses using these methods are presented, as well as results from a very large calculation with statistical uncertainties that approach what is needed for design applications. (authors)
Benchmark Solution For The Category 3, Problem 2: Cascade - Gust Interaction
NASA Technical Reports Server (NTRS)
Envia, Edmane
The benchmark solution for the cascade-gust interaction problem is computed using a linearized Euler code called LINFLUX. The inherently three-dimensional code is run in the thin-annulus limit to compute the two-dimensional cascade response. The calculations are carried out in the frequency-domain and the unsteady response at each of the gust s three frequency component is computed. The results are presented on modal basis for pressure perturbations (i.e., acoustic modes) as well as velocity perturbations (i.e., convected gust modes) at each frequency.
ICASE/LaRC Workshop on Benchmark Problems in Computational Aeroacoustics (CAA)
NASA Technical Reports Server (NTRS)
Hardin, Jay C. (editor); Ristorcelli, J. Ray (editor); Tam, Christopher K. W. (editor)
The proceedings of the Benchmark Problems in Computational Aeroacoustics Workshop held at NASA Langley Research Center are the subject of this report. The purpose of the Workshop was to assess the utility of a number of numerical schemes in the context of the unusual requirements of aeroacoustical calculations. The schemes were assessed from the viewpoint of dispersion and dissipation -- issues important to long time integration and long distance propagation in aeroacoustics. Also investigated were the effect of implementation of different boundary conditions. The Workshop included a forum in which practical engineering problems related to computational aeroacoustics were discussed. This discussion took the form of a dialogue between an industrial panel and the workshop participants and was an effort to suggest the direction of evolution of this field in the context of current engineering needs.
Integrating CFD, CAA, and Experiments Towards Benchmark Datasets for Airframe Noise Problems
NASA Technical Reports Server (NTRS)
Choudhari, Meelan M.; Yamamoto, Kazuomi
Airframe noise corresponds to the acoustic radiation due to turbulent flow in the vicinity of airframe components such as high-lift devices and landing gears. The combination of geometric complexity, high Reynolds number turbulence, multiple regions of separation, and a strong coupling with adjacent physical components makes the problem of airframe noise highly challenging. Since 2010, the American Institute of Aeronautics and Astronautics has organized an ongoing series of workshops devoted to Benchmark Problems for Airframe Noise Computations (BANC). The BANC workshops are aimed at enabling a systematic progress in the understanding and high-fidelity predictions of airframe noise via collaborative investigations that integrate state of the art computational fluid dynamics, computational aeroacoustics, and in depth, holistic, and multifacility measurements targeting a selected set of canonical yet realistic configurations. This paper provides a brief summary of the BANC effort, including its technical objectives, strategy, and selective outcomes thus far.
Darcy multi-domain approach for coupling surface-subsurface flows: application to benchmark problems
NASA Astrophysics Data System (ADS)
Mugler, Claude; Mouche, Emmanuel
A fully integrated coupling between surface and subsurface flows has been implemented during these last years (Weill et al., J. Hydrol., 2009). This model unifies the Richards and the diffusive wave equations into a single generalized Richards equation defined in a single domain composed of surface and subsurface subdomains. The unified equation is solved with a Picard iterative scheme in the Cast3M numerical framework (www-cast3m.cea.fr). This model has been applied successfully to 2D configurations (Abdul and Gilham, Water Resour. Res. 1984; Ogden and Watts, Water Resour. Res. 2000). It also allowed us to simulate several theoretical benchmark test cases involving the runoff production by excess saturation or by excess infiltration, and the runon-runoff processes on a heterogeneous soil (Kollet and Maxwell, Adv. Water Res. 2006; Sulis et al., Adv. Water Res. 2010, Maxwell et al., Water Resour. Res. 2014). We will present our last simulation results of benchmark problems proposed by S.J. Kollet and R.M. Maxwell during the 2nd Integrated Hydrologic Model Intercomparison Workshop which was held at the University of Bonn on June 2013: the 3D tilted V-catchment and the Super-slab case.
C5 Benchmark Problem with Discrete Ordinate Radiation Transport Code DENOVO
Yesilyurt, Gokhan [ORNL; Clarno, Kevin T [ORNL; Evans, Thomas M [ORNL; Davidson, Gregory G [ORNL; Fox, Patricia B [ORNL
The C5 benchmark problem proposed by the Organisation for Economic Co-operation and Development/Nuclear Energy Agency was modeled to examine the capabilities of Denovo, a three-dimensional (3-D) parallel discrete ordinates (S{sub N}) radiation transport code, for problems with no spatial homogenization. Denovo uses state-of-the-art numerical methods to obtain accurate solutions to the Boltzmann transport equation. Problems were run in parallel on Jaguar, a high-performance supercomputer located at Oak Ridge National Laboratory. Both the two-dimensional (2-D) and 3-D configurations were analyzed, and the results were compared with the reference MCNP Monte Carlo calculations. For an additional comparison, SCALE/KENO-V.a Monte Carlo solutions were also included. In addition, a sensitivity analysis was performed for the optimal angular quadrature and mesh resolution for both the 2-D and 3-D infinite lattices of UO{sub 2} fuel pin cells. Denovo was verified with the C5 problem. The effective multiplication factors, pin powers, and assembly powers were found to be in good agreement with the reference MCNP and SCALE/KENO-V.a Monte Carlo calculations.
Solutions of the benchmark problems by the dispersion-relation-preserving scheme
NASA Technical Reports Server (NTRS)
Tam, Christopher K. W.; Shen, H.; Kurbatskii, K. A.; Auriault, L.
The 7-point stencil Dispersion-Relation-Preserving scheme of Tam and Webb is used to solve all the six categories of the CAA benchmark problems. The purpose is to show that the scheme is capable of solving linear, as well as nonlinear aeroacoustics problems accurately. Nonlinearities, inevitably, lead to the generation of spurious short wave length numerical waves. Often, these spurious waves would overwhelm the entire numerical solution. In this work, the spurious waves are removed by the addition of artificial selective damping terms to the discretized equations. Category 3 problems are for testing radiation and outflow boundary conditions. In solving these problems, the radiation and outflow boundary conditions of Tam and Webb are used. These conditions are derived from the asymptotic solutions of the linearized Euler equations. Category 4 problems involved solid walls. Here, the wall boundary conditions for high-order schemes of Tam and Dong are employed. These conditions require the use of one ghost value per boundary point per physical boundary condition. In the second problem of this category, the governing equations, when written in cylindrical coordinates, are singular along the axis of the radial coordinate. The proper boundary conditions at the axis are derived by applying the limiting process of r approaches 0 to the governing equations. The Category 5 problem deals with the numerical noise issue. In the present approach, the time-independent mean flow solution is computed first. Once the residual drops to the machine noise level, the incident sound wave is turned on gradually. The solution is marched in time until a time-periodic state is reached. No exact solution is known for the Category 6 problem. Because of this, the problem is formulated in two totally different ways, first as a scattering problem then as a direct simulation problem. There is good agreement between the two numerical solutions. This offers confidence in the computed results. Both formulations are solved as initial value problems. As such, no Kutta condition is required at the trailing edge of the airfoil.
Helmholtz and parabolic equation solutions to a benchmark problem in ocean acoustics.
Larsson, Elisabeth; Abrahamsson, Leif
The Helmholtz equation (HE) describes wave propagation in applications such as acoustics and electromagnetics. For realistic problems, solving the HE is often too expensive. Instead, approximations like the parabolic wave equation (PE) are used. For low-frequency shallow-water environments, one persistent problem is to assess the accuracy of the PE model. In this work, a recently developed HE solver that can handle a smoothly varying bathymetry, variable material properties, and layered materials, is used for an investigation of the errors in PE solutions. In the HE solver, a preconditioned Krylov subspace method is applied to the discretized equations. The preconditioner combines domain decomposition and fast transform techniques. A benchmark problem with upslope-downslope propagation over a penetrable lossy seamount is solved. The numerical experiments show that, for the same bathymetry, a soft and slow bottom gives very similar HE and PE solutions, whereas the PE model is far from accurate for a hard and fast bottom. A first attempt to estimate the error is made by computing the relative deviation from the energy balance for the PE solution. This measure gives an indication of the magnitude of the error, but cannot be used as a strict error bound. PMID:12765364
Evaluating Heat Pipe Performance in 1/6 g Acceleration: Problems and Prospects
NASA Technical Reports Server (NTRS)
Jaworske, Donald A.; McCollum, Timothy A.; Gibson, Marc A.; Sanzi, James L.; Sechkar, Edward A.
Heat pipes composed of titanium and water are being considered for use in the heat rejection system of a fission power system option for lunar exploration. Placed vertically on the lunar surface, the heat pipes would operate as thermosyphons in the 1/6 g environment. The design of thermosyphons for such an application is determined, in part, by the flooding limit. Flooding is composed of two components, the thickness of the fluid film on the walls of the thermosyphon and the interaction of the fluid flow with the concurrent vapor counter flow. Both the fluid thickness contribution and interfacial shear contribution are inversely proportional to gravity. Hence, evaluating the performance of a thermosyphon in a 1 g environment on Earth may inadvertently lead to overestimating the performance of the same thermosyphon as experienced in the 1/6 g environment on the moon. Several concepts of varying complexity have been proposed for evaluating thermosyphon performance in reduced gravity, ranging from tilting the thermosyphons on Earth based on a cosine function, to flying heat pipes on a low-g aircraft. This paper summarizes the problems and prospects for evaluating thermosyphon performance in 1/6 g.
Results from the multi-species benchmark problem 3 (BM3) using two-dimensional models.
Noguera, D R; Picioreanu, C
In addition to the one-dimensional solutions of a multi-species benchmark problem (BM3) presented earlier (Rittmann et al., 2004), we offer solutions using two-dimensional (2-D) models. Both 2-D models (called here DN and CP) used numerical solutions to BM3 based on a similar mathematical framework of the one-dimensional AQUASIM-built models submitted by Wanner (model W) and Morgenroth (model M1), described in detail elsewhere (Rittmann et al., 2004). The CP model used differential equations to simulate substrate gradients and biomass growth and a particle-based approach to describe biomass division and biofilm growth. The DN model simulated substrate and biomass using a cellular automaton approach. For several conditions stipulated in BM3, the multidimensional models provided very similar results to the 1-D models in terms of bulk substrate concentrations and fluxes into the biofilm. The similarity can be attributed to the definition of BM3, which restricted the problem to a flat biofilm in contact with a completely mixed liquid phase, and therefore, without any salient characteristics to be captured in a multidimensional domain. On the other hand, the models predicted significantly different accumulations of the different types of biomass, likely reflecting differences in the way biomass spread within the biofilm is simulated. PMID:15303738
Generational PipeLined Genetic Algorithm (PLGA) using Stochastic Selection
De, Rajat Kumar
Generational PipeLined Genetic Algorithm (PLGA) using Stochastic Selection Malay K. Pakhira and Rajat K. De Abstract-- In this paper, a pipelined version of genetic algorithm, called PLGA (PLGA). A number of benchmark problems are used to compare the performances of conventional roulette
Modular axial grooved heat pipes
H. Koch; H. Kreeb; M. Perdu
A modular axial grooved heat pipe system operable between 100 and 400 K was developed. Accent was placed on typical space application problems such as assembly of two heat pipes (interface problems), circular heat pipes, construction of radiators, long life behavior, and cryogenic heat pipes. Results of performance tests on this heat pipe system designed for a space radiator to
Comparative analysis of nine structural codes used in the second WIPP benchmark problem
Morgan, H.S.; Krieg, R.D.; Matalucci, R.V.
In the Waste Isolation Pilot Plant (WIPP) Benchmark II study, various computer codes were compared on the basis of their capabilities for calculating the response of hypothetical drift configurations for nuclear waste experiments and storage demonstration. The codes used by participants in the study were ANSALT, DAPROK, JAC, REM, SANCHO, SPECTROM, STEALTH, and two different implementations of MARC. Errors were found in the preliminary results, and several calculations were revised. Revised solutions were in reasonable agreement except for the REM solution. The Benchmark II study allowed significant advances in understanding the relative behavior of computer codes available for WIPP calculations. The study also pointed out the possible need for performing critical design calculations with more than one code. Lastly, it indicated the magnitude of the code-to-code spread in results which is to be expected even when a model has been explicitly defined.
Mesoscale Benchmark Demonstration Problem 1: Mesoscale Simulations of Intra-granular Fission Gas Bubbles in UO2 under Post-irradiation Thermal Annealing
Li, Yulan; Hu, Shenyang Y.; Montgomery, Robert; Gao, Fei; Sun, Xin; Tonks, Michael; Biner, Bullent; Millet, Paul; Tikare, Veena; Radhakrishnan, Balasubramaniam; Andersson , David
A study was conducted to evaluate the capabilities of different numerical methods used to represent microstructure behavior at the mesoscale for irradiated material using an idealized benchmark problem. The purpose of the mesoscale benchmark problem was to provide a common basis to assess several mesoscale methods with the objective of identifying the strengths and areas of improvement in the predictive modeling of microstructure evolution. In this work, mesoscale models (phase-field, Potts, and kinetic Monte Carlo) developed by PNNL, INL, SNL, and ORNL were used to calculate the evolution kinetics of intra-granular fission gas bubbles in UO2 fuel under post-irradiation thermal annealing conditions. The benchmark problem was constructed to include important microstructural evolution mechanisms on the kinetics of intra-granular fission gas bubble behavior such as the atomic diffusion of Xe atoms, U vacancies, and O vacancies, the effect of vacancy capture and emission from defects, and the elastic interaction of non-equilibrium gas bubbles. An idealized set of assumptions was imposed on the benchmark problem to simplify the mechanisms considered. The capability and numerical efficiency of different models are compared against selected experimental and simulation results. These comparisons find that the phase-field methods, by the nature of the free energy formulation, are able to represent a larger subset of the mechanisms influencing the intra-granular bubble growth and coarsening mechanisms in the idealized benchmark problem as compared to the Potts and kinetic Monte Carlo methods. It is recognized that the mesoscale benchmark problem as formulated does not specifically highlight the strengths of the discrete particle modeling used in the Potts and kinetic Monte Carlo methods. Future efforts are recommended to construct increasingly more complex mesoscale benchmark problems to further verify and validate the predictive capabilities of the mesoscale modeling methods used in this study.
Summary of the Tandem Cylinder Solutions from the Benchmark Problems for Airframe Noise Computations-I Workshop
NASA Technical Reports Server (NTRS)
Lockard, David P.
Fifteen submissions in the tandem cylinders category of the First Workshop on Benchmark problems for Airframe Noise Computations are summarized. Although the geometry is relatively simple, the problem involves complex physics. Researchers employed various block-structured, overset, unstructured and embedded Cartesian grid techniques and considerable computational resources to simulate the flow. The solutions are compared against each other and experimental data from 2 facilities. Overall, the simulations captured the gross features of the flow, but resolving all the details which would be necessary to compute the noise remains challenging. In particular, how to best simulate the effects of the experimental transition strip, and the associated high Reynolds number effects, was unclear. Furthermore, capturing the spanwise variation proved difficult.
Two and Three Dimensional Nonlocal DFT for Inhomogeneous Fluids II: Solvated Polymers as a Benchmark Problem
Frink, Laura J. Douglas; Salinger, Andrew G.
In a previous companion paper, we presented the details of our algorithms for performing nonlocal density functional theory (DFT) calculations in complex 2D and 3D geometries. We discussed scaling and parallelization, but did not discuss other issues of performance. In this paper, we detail the precision of our methods with respect to changes in the mesh spacing. This is a complex issue because given a Cartesian mesh, changes in mesh spacing will result in changes in surface geometry. We discuss these issue using a series of rigid solvated polymer models including square rod polymers, cylindrical polymers, and bead-chain polymers. By comparing the results of the various models, it becomes clear that surface curvature or roughness plays an important role in determining the strength of structural solvation forces between interacting solvated polymers. The results in this paper serve as benchmarks for future application of these algorithms to complex fluid systems.
A Hydrochemical Hybrid Code for Astrophysical Problems. I. Code Verification and Benchmarks for Photon-Dominated Region (PDR)
Motoyama, Kazutaka; Shang, Hsien; Krasnopolsky, Ruben; Hasegawa, Tatsuhiko
A two dimensional hydrochemical hybrid code, KM2, is constructed to deal with astrophysical problems that would require coupled hydrodynamical and chemical evolution. The code assumes axisymmetry in cylindrical coordinate system, and consists of two modules: a hydrodynamics module and a chemistry module. The hydrodynamics module solves hydrodynamics using a Godunov-type finite volume scheme and treats included chemical species as passively advected scalars. The chemistry module implicitly solves non-equilibrium chemistry and change of the energy due to thermal processes with transfer of external ultraviolet radiation. Self-shielding effects on photodissociation of CO and H$_2$ are included. In this introductory paper, the adopted numerical method is presented, along with code verifications using the hydrodynamics modules, and a benchmark on the chemistry module with reactions specific to a photon-dominated region (PDR). Finally, as an example of the expected capability, the hydrochemical evolution of a PDR is...
Analysis of chlorinated polyvinyl chloride pipe burst problems :Vasquez residence system inspection.
Black, Billy D.; Menicucci, David F.; Harrison, John (Florida Solar Energy Center)
This report documents the investigation regarding the failure of CPVC piping that was used to connect a solar hot water system to standard plumbing in a home. Details of the failure are described along with numerous pictures and diagrams. A potential failure mechanism is described and recommendations are outlined to prevent such a failure.
Analysing the Adaptation Level of Parallel Hyperheuristics Applied to Multiobjectivised Benchmark Problems
Carlos Segura; Eduardo Segredo; Coromoto Leon
Evolutionary Algorithms (EAs) are one of the most popular strategies for solving optimisation problems. Several variants of EAs are seen to exist. They usually have several components and parameters which must be fixed. Therefore, one of the main drawbacks of EAs is the complexity of their parameter setting. Multiobjectivisation consists in the reformulation of mono-objective problems as multi-objective ones. Multiobjectivisation
Benchmarking a Wide Spectrum of Metaheuristic Techniques for the Radio Network Design Problem
Silvio Priem-Mendes; Guillermo Molina; Miguel A. Vega-Rodr�guez; Juan Antonio G�mez Pulido; Yago S�ez; Gara Miranda; Carlos Segura; Enrique Alba; Pedro Isasi; Coromoto Le�n; Juan Manuel S�nchez-P�rez
The radio network design (RND) is an NP-hard optimization problem which consists of the maximization of the coverage of a given area while minimizing the base station deployment. Solving RND problems efficiently is relevant to many fields of application and has a direct impact in the engineering, telecommunication, scientific, and industrial areas. Numerous works can be found in the literature
Benchmarking the SPHINX and CTH shock physics codes for three problems in ballistics
Wilson, L.T. [Naval Surface Warfare Center, Dahlgren, VA (United States); Hertel, E. [Sandia National Labs., Albuquerque, NM (United States); Schwalbe, L.; Wingate, C. [Los Alamos National Lab., NM (United States)
The CTH Eulerian hydrocode, and the SPHINX smooth particle hydrodynamics (SPH) code were used to model a shock tube, two long rod penetrations into semi-infinite steel targets, and a long rod penetration into a spaced plate array. The results were then compared to experimental data. Both SPHINX and CTH modeled the one-dimensional shock tube problem well. Both codes did a reasonable job in modeling the outcome of the axisymmetric rod impact problem. Neither code correctly reproduced the depth of penetration in both experiments. In the 3-D problem, both codes reasonably replicated the penetration of the rod through the first plate. After this, however, the predictions of both codes began to diverge from the results seen in the experiment. In terms of computer resources, the run times are problem dependent, and are discussed in the text.
Sensitivity of MCNP5 calculations for a spherical numerical benchmark problem to the angular scattering distributions for deuterium
Kozier, K. S. [Atomic Energy of Canada Limited, Chalk River Laboratories, Chalk River, Ont. K0J 1J0 (Canada)
This paper examines the sensitivity of MCNP5 k{sub eff} results to various deuterium data files for a simple benchmark problem consisting of an 8.4-cm radius sphere of uranium surrounded by an annulus of deuterium at the nuclide number density corresponding to heavy water. This study was performed to help clarify why {Delta}k{sub eff} values of about 10 mk are obtained when different ENDF/B deuterium data files are used in simulations of critical experiments involving solutions of high-enrichment uranyl fluoride in heavy water, while simulations of low-leakage, heterogeneous critical lattices of natural-uranium fuel rods in heavy water show differences of <1 mk. The benchmark calculations were performed as a function of deuterium reflector thickness for several uranium compositions using deuterium ACE files derived from ENDF/B-VII.b1 (release beta 1), ENDF/B-VI.4 and JENDL-3.3, which differ primarily in the energy/angle distributions for elastic scattering <3.2 MeV. Calculations were also performed using modified ACE files having equiprobable cosine bin values in the centre-of-mass reference frame in a progressive manner with increasing energy. It was found that the {Delta}k{sub eff} values increased with deuterium reflector thickness and uranium enrichment. The studies using modified ACE files indicate that most of the reactivity differences arise at energies <1 MeV; hence, this energy range should be given priority if new scattering distribution measurements are undertaken. (authors)
Constant-concentration boundary condition: Lessons from the HYDROCOIN variable-density groundwater benchmark problem
Konikow, L.F.; Sanford, W.E.; Campbell, P.J.
In a solute-transport model, if a constant-concentration boundary condition is applied at a node in an active flow field, a solute flux can occur by both advective and dispersive processes. The potential for advective release is demonstrated by reexamining the Hydrologic Code Intercomparison (HYDROCOIN) project case 5 problem, which represents a salt dome overlain by a shallow groundwater system. The resulting flow field includes significant salinity and fluid density variations. Several independent teams simulated this problem using finite difference or finite element numerical models. We applied a method-of-characteristics model (MOCDENSE). The previous numerical implementations by HYDROCOIN teams of a constant-concentration boundary to represent salt release by lateral dispersion only (as stipulated in the original problem definition) was flawed because this boundary condition allows the release of salt into the flow field by both dispersion and advection. When the constant-concentration boundary is modified to allow salt release by dispersion only, significantly less salt is released into the flow field. The calculated brine distribution for case 5 depends very little on which numerical model is used, as long as the selected model is solving the proper equations. Instead, the accuracy of the solution depends strongly on the proper conceptualization of the problem, including the detailed design of the constant-concentration boundary condition. The importance and sensitivity to the manner of specification of this boundary does not appear to have been recognized previously in the analysis of this problem.
Applicability domains for classification problems: benchmarking of distance to models for AMES mutagenicity set
For QSAR and QSPR modeling of biological and physicochemical properties, estimating the accuracy of predictions is a critical problem. The ?distance to model? (DM) can be defined as a metric that defines the similarity between the training set molecules and the test set compound ...
Finite-element/progressive-lattice-sampling response surface methodology and application to benchmark probability quantification problems
Romero, V.J.; Bankston, S.D.
Optimal response surface construction is being investigated as part of Sandia discretionary (LDRD) research into Analytic Nondeterministic Methods. The goal is to achieve an adequate representation of system behavior over the relevant parameter space of a problem with a minimum of computational and user effort. This is important in global optimization and in estimation of system probabilistic response, which are both made more viable by replacing large complex computer models with fast-running accurate and noiseless approximations. A Finite Element/Lattice Sampling (FE/LS) methodology for constructing progressively refined finite element response surfaces that reuse previous generations of samples is described here. Similar finite element implementations can be extended to N-dimensional problems and/or random fields and applied to other types of structured sampling paradigms, such as classical experimental design and Gauss, Lobatto, and Patterson sampling. Here the FE/LS model is applied in a ``decoupled`` Monte Carlo analysis of two sets of probability quantification test problems. The analytic test problems, spanning a large range of probabilities and very demanding failure region geometries, constitute a good testbed for comparing the performance of various nondeterministic analysis methods. In results here, FE/LS decoupled Monte Carlo analysis required orders of magnitude less computer time than direct Monte Carlo analysis, with no appreciable loss of accuracy. Thus, when arriving at probabilities or distributions by Monte Carlo, it appears to be more efficient to expend computer-model function evaluations on building a FE/LS response surface than to expend them in direct Monte Carlo sampling.
A reference book on pipes, pipe fitting, and pipe treatment in the petroleum and natural gas industries is presented. The contents include: standard piping terminology; piping codes and standards; pipe manufacturing sizes; metallic piping; non-metallic piping; lined and coated piping systems; pipe tracing and jacketing; fittings and flanges; piping connections; valves; pipe expansion devices; flexible piping; piping specialties; pipe supports
Robust H-infinity control synthesis method and its application to benchmark problems
NASA Technical Reports Server (NTRS)
Wie, Bong; Liu, Qiang; Byun, Kuk-Whan
This paper presents a robust H-infinity control synthesis method for structured parameter uncertainty. The robust H-infinity control design methodology is also incorporated with the so-called internal model principle for persistent-disturbance rejection. A noncollocated control problem of flexible space structures subject to parameter variations is used to illustrate the design methodology. It is shown that the proposed design method invariably makes use of nonminimum-phase compensation and that it achieves the desired asymptotic disturbance rejection by having a disturbance rejection 'dipole'.
Inhomogeneous temperature problems inside a Li/SOCl2 cell - Homogenization by integrated heat pipes
NASA Astrophysics Data System (ADS)
Lefriec, C.; Suleiman, A.; Alexandre, A.
The effect of the temperature gradient on the electrical capacity of the lithium/thionyl chloride (Li/SOCl2) cells and the dependence of internal heat generation on the temperature level were investigated by studying the thermal behavior of a cell constituted by a number of couples stacken in a stainless steel cylinder during a discharge profile. It is shown that the temperature gradient between couples affected the depth of discharge, indicating that this gradient must be limited to prevent discrepancy in couple's voltage and inversion phenomenon. It was found that a cooling concept based on integrated heat pipes is effective in reducing the temperature gradient and in yielding homogeneous cell behavior in overdischarge.
Assumed-strain solid�shell formulation for the six-node finite element SHB6: evaluation on non-linear benchmark problems
Farid Abed-Meraim; Vuong-Dieu Trinh; Alain Combescure
The current contribution proposes a six-node prismatic solid�shell denoted as (SHB6). The formulation is extended to geometric and material non-linearities, and focus will be placed on its validation on non-linear benchmark problems. The resulting derivation only involves displacement DOF, as it is based on a fully 3D approach. The motivation behind this is to allow a natural mesh connexion in
NASA Technical Reports Server (NTRS)
Small Business Innovation Research contracts from Goddard Space Flight Center to Thermacore Inc. have fostered the company work on devices tagged "heat pipes" for space application. To control the extreme temperature ranges in space, heat pipes are important to spacecraft. The problem was to maintain an 8-watt central processing unit (CPU) at less than 90 C in a notebook computer using no power, with very little space available and without using forced convection. Thermacore's answer was in the design of a powder metal wick that transfers CPU heat from a tightly confined spot to an area near available air flow. The heat pipe technology permits a notebook computer to be operated in any position without loss of performance. Miniature heat pipe technology has successfully been applied, such as in Pentium Processor notebook computers. The company expects its heat pipes to accommodate desktop computers as well. Cellular phones, camcorders, and other hand-held electronics are forsible applications for heat pipes.
Merrigan, M.A.
Test heat pipes have been operated in the 1400 K to 1700 K range for periods in excess of 20,000 hours with the objective of understanding and controlling corrosion and failure mechanisms. The results of a post test analysis of one of these heat pipes that was operated for 25,216 hours at 1700 K are reviewed and the implications for heat pipe lifetime discussed. An in-process report of an investigation of transient heat pipe behavior is presented. This investigation is being conducted as a result of restart problems encountered during life test of a 2 m. radiation cooled heat pipe. The results of a series of shut-down tests from power and temperature are given and probable causes of the restart problem discussed.
Hg supply piping simulation Stony Brook University
McDonald, Kirk
Hg supply piping simulation (No MHD) Stony Brook University Yan Zhan Prof. Foluso Ladeinde July 2nd, 2010 #12;Outline � Hg supply piping in Muon Collider � Turbulence models for bend pipe flow � Problems need studying � Arrangements in the near future #12;Outline � Hg supply piping in Muon Collider � Hg
The SEQUOIA 2000 storage benchmark
Michael Stonebraker; Jim Frew; Kenn Gardels; Jeff Meredith
This paper presents a benchmark that concisely captures the data base requirements of a collection of Earth Scientists working in the SEQUOIA 2000 project on various aspects of global change research. This benchmark has the novel characteristic that it uses real data sets and real queries that are representative of Earth Science tasks. Because it appears that Earth Science problems
U. R. Christensen; J. Aubert; P. Cardin; E. Dormy; S. Gibbons; G. A. Glatzmaier; E. Grote; Y. Honkura; C. Jones; M. Kono; M. Matsushima; A. Sakuraba; F. Takahashi; A. Tilgner; J. Wicht; K. Zhang
We present the results of a benchmark study for a convection-driven magnetohydrodynamic dynamo problem in a rotating spherical shell. The solutions are stationary aside from azimuthal drift. One case of non-magnetic convection and two dynamos that differ in the assumptions concerning the inner core are studied. Six groups contributed numerical solutions which show good agreement. This provides an accurate reference
ERIC Educational Resources Information Center
Lewis, J.
Describes the construction, function, and applications of heat pipes. Suggests using the heat pipe to teach principles related to heat transfer and gives sources for obtaining instructional kits for this purpose. (GS)
Applications of Integral Benchmark Data
Giuseppe Palmiotti; Teruhiko Kugo; Fitz Trumble; Albert C. (Skip) Kahler; Dale Lancaster
The International Reactor Physics Experiment Evaluation Project (IRPhEP) and the International Criticality Safety Benchmark Evaluation Project (ICSBEP) provide evaluated integral benchmark data that may be used for validation of reactor physics / nuclear criticality safety analytical methods and data, nuclear data testing, advanced modeling and simulation, and safety analysis licensing activities. The handbooks produced by these programs are used in over 30 countries. Five example applications are presented in this paper: (1) Use of IRPhEP Data in Uncertainty Analyses and Cross Section Adjustment, (2) Uncertainty Evaluation Methods for Reactor Core Design at JAEA Using Reactor Physics Experimental Data, (3) Application of Benchmarking Data to a Broad Range of Criticality Safety Problems, (4) Cross Section Data Testing with ICSBEP Benchmarks, and (5) Use of the International Handbook of Evaluated Reactor Physics Benchmark Experiments to Support the Power Industry.
A stabilized mixed finite element method for shear-rate dependent non-Newtonian fluids: 3D benchmark problems and application to blood flow in bifurcating arteries
NASA Astrophysics Data System (ADS)
Kwack, JaeHyuk; Masud, Arif
This paper presents a stabilized mixed finite element method for shear-rate dependent fluids. The nonlinear viscosity field is a function of the shear-rate and varies uniformly in space and in time. The stabilized form is developed via application of Variational Multiscale (VMS) framework to the underlying generalized Navier-Stokes equation. Linear and quadratic tetrahedral and hexahedral elements are employed with equal-order interpolations for the velocity and pressure fields. A variety of benchmark problems are solved to assess the stability and accuracy properties of the resulting method. The method is then applied to non-Newtonian shear-rate dependent flows in bifurcating artery geometry, and significant non-Newtonian fluid effects are observed. A comparative study of the proposed method shows that the additional computational costs due to the nonlinear shear-rate dependent viscosity are only ten percent more than the computational cost for a Newtonian model.
Benchmarking in technical information
Terrence D. Sole; Gary Bist
Benchmarking is rapidly becoming a standard business practice used by organizations to improve their quality in specific areas. Though benchmarking previously has been associated with product comparisons, such as benchmarking the performance of one product with another, process benchmarking is becoming equally important. This paper, based on a recently conducted benchmark, discusses why you might consider benchmarking an aspect of
Applications of the Space-Time Conservation Element and Solution Element (CE/SE) Method to Computational Aeroacoustic Benchmark Problems
NASA Technical Reports Server (NTRS)
Wang, Xiao-Yen; Himansu, Ananda; Chang, Sin-Chung; Jorgenson, Philip C. E.
The Internal Propagation problems, Fan Noise problem, and Turbomachinery Noise problems are solved using the space-time conservation element and solution element (CE/SE) method. The problems in internal propagation problems address the propagation of sound waves through a nozzle. Both the nonlinear and linear quasi 1D Euler equations are solved. Numerical solutions are presented and compared with the analytical solution. The fan noise problem concerns the effect of the sweep angle on the acoustic field generated by the interaction of a convected gust with a cascade of 3D flat plates. A parallel version of the 3D CE/SE Euler solver is developed and employed to obtain numerical solutions for a family of swept flat plates. Numerical solutions for sweep angles of 0, 5, 10, and 15 deg are presented. The turbomachinery problems describe the interaction of a 2D vortical gust with a cascade of flat-plate airfoils with/without a downstream moving grid. The 2D nonlinear Euler Equations are solved and the converged numerical solutions are presented and compared with the corresponding analytical solution. All the comparisons demonstrate that the CE/SE method is capable of solving aeroacoustic problems with/without shock waves in a simple and efficient manner. Furthermore, the simple non-reflecting boundary condition used in the CE/SE method which is not based on the characteristic theory works very well in 1D, 2D and 3D problems.
The DaCapo benchmarks: java benchmarking development and analysis
Stephen M. Blackburn; Robin Garner; Chris Hoffmann; Asjad M. Khan; Kathryn S. Mckinley; Rotem Bentzur; Amer Diwan; Daniel Feinberg; Daniel Frampton; Samuel Z. Guyer; Martin Hirzel; Antony L. Hosking; Maria Jump; Han Bok Lee; J. Eliot B. Moss; Aashish Phansalkar; Darko Stefanovic; Thomas Vandrunen; Daniel Von Dincklage; Ben Wiedermann
Since benchmarks drive computer science research and industry product development, which ones we use and how we evaluate them are key questions for the community. Despite complex run-time tradeoffs due to dynamic compilation and garbage collection required for Java programs, many evaluations still use methodolo-gies developed for C, C++, and Fortran. SPEC, the dominant pur-veyor of benchmarks, compounded this problem
Issues in Benchmark Metric Selection
NASA Astrophysics Data System (ADS)
Crolotte, Alain
It is true that a metric can influence a benchmark but will esoteric metrics create more problems than they will solve? We answer this question affirmatively by examining the case of the TPC-D metric which used the much debated geometric mean for the single-stream test. We will show how a simple choice influenced the benchmark and its conduct and, to some extent, DBMS development. After examining other alternatives our conclusion is that the �real� measure for a decision-support benchmark is the arithmetic mean.
High temperature heat pipe experiments aboard the space shuttle
Woloshun, K.A.; Merrigan, M.A.; Sena, J.T. (Los Alamos National Laboratory, P.O. Box 1663, Mail Stop J576, Los Alamos, New Mexico 87545 (United States)); Secary, C.J. (PL/VTPT, Kirtland AFB, Albuquerque, New Mexico 87117 (United States))
Although high temperature, liquid metal heat pipe radiators have become a standard component on most space nuclear power systems, there is no experimental data on the operation of these heat pipes in a zero gravity or micro gravity environment. Experiments to benchmark the transient and steady state performance of prototypical heat pipe space radiator elements are in preparation. Three SST/potassium heat pipes are being designed, fabricated, and ground tested. It is anticipated that these heat pipes will fly aboard the space shuttle in 1995. Three wick structures will be tested: homogeneous, arterial, and annular gap. Ground tests are described that simulate the space shuttle environment in every way except gravity field.
Three-dimensional instability of axisymmetric flows: solution of benchmark problems by a low-order finite volume method
Alexander Y. Gelfgat
SUMMARY Several problems on three-dimensional instability of axisymmetric steady flows driven by convection or rotation or both are studied by a second-order finite volume method combined with the Fourier decomposition in the periodic azimuthal direction. The study is focused on the convergence of the critical parameters with mesh refinement. The calculations are done on the uniform and stretched grids with
NASA Technical Reports Server (NTRS)
Yee, Karl Y.; Ganapathi, Gani B.; Sunada, Eric T.; Bae, Youngsam; Miller, Jennifer R.; Beinsford, Daniel F.
Improved methods of heat dissipation are required for modern, high-power density electronic systems. As increased functionality is progressively compacted into decreasing volumes, this need will be exacerbated. High-performance chip power is predicted to increase monotonically and rapidly with time. Systems utilizing these chips are currently reliant upon decades of old cooling technology. Heat pipes offer a solution to this problem. Heat pipes are passive, self-contained, two-phase heat dissipation devices. Heat conducted into the device through a wick structure converts the working fluid into a vapor, which then releases the heat via condensation after being transported away from the heat source. Heat pipes have high thermal conductivities, are inexpensive, and have been utilized in previous space missions. However, the cylindrical geometry of commercial heat pipes is a poor fit to the planar geometries of microelectronic assemblies, the copper that commercial heat pipes are typically constructed of is a poor CTE (coefficient of thermal expansion) match to the semiconductor die utilized in these assemblies, and the functionality and reliability of heat pipes in general is strongly dependent on the orientation of the assembly with respect to the gravity vector. What is needed is a planar, semiconductor-based heat pipe array that can be used for cooling of generic MCM (multichip module) assemblies that can also function in all orientations. Such a structure would not only have applications in the cooling of space electronics, but would have commercial applications as well (e.g. cooling of microprocessors and high-power laser diodes). This technology is an improvement over existing heat pipe designs due to the finer porosity of the wick, which enhances capillary pumping pressure, resulting in greater effective thermal conductivity and performance in any orientation with respect to the gravity vector. In addition, it is constructed of silicon, and thus is better suited for the cooling of semiconductor devices.
D. Bailey; E. Barszcz; J. Barton; D. Browning; R. Carter; L. Dagum
A new set of benchmarks has been developed for the performance evaluation of highly parallel supercomputers. These benchmarks consist of five parallel kernels and three simulated application benchmarks. Together theymimic the computation and data movement characteristics of large scale computational fluid dynamics (CFD) applications.The principal distinguishing feature of these benchmarks is their penciland paper specification---all details of these benchmarks are
Benchmarking Query Execution Robustness
NASA Astrophysics Data System (ADS)
Wiener, Janet L.; Kuno, Harumi; Graefe, Goetz
Benchmarks that focus on running queries on a well-tuned database system ignore a long-standing problem: adverse runtime conditions can cause database system performance to vary widely and unexpectedly. When the query execution engine does not exhibit resilience to these adverse conditions, addressing the resultant performance problems can contribute significantly to the total cost of ownership for a database system in over-provisioning, lost efficiency, and increased human administrative costs. For example, focused human effort may be needed to manually invoke workload management actions or fine-tune the optimization of specific queries.
High temperature heat pipe experiments in low earth orbit
Woloshun, K.; Merrigan, M.A.; Sena, J.T. [Los Alamos National Lab., NM (United States); Critchley, E. [Phillips Lab., Kirtland AFB, NM (United States)
Although high temperature, liquid metal heat pipe radiators have become a standard component on most high power space power system designs, there is no experimental data on the operation of these heat pipes in a zero gravity or micro-gravity environment. Experiments to benchmark the transient and steady state performance of prototypical heat pipe space radiator elements are in preparation for testing in low earth orbit. It is anticipated that these heat pipes will be tested aborad the Space Shuttle in 1995. Three heat pipes will be tested in a cargo bay Get Away Special (GAS) canister. The heat pipes are SST/potassium, each with a different wick structure; homogeneous, arterial, and annular gap, the heat pipes have been designed, fabricated, and ground tested. In this paper, the heat pipe designs are specified, and transient and steady-state ground test data are presented.
High temperature heat pipe experiments in low earth orbit
Woloshun, K.; Merrigan, M.A.; Sena, J.T. (Los Alamos National Lab., NM (United States)); Critchley, E. (Phillips Lab., Kirtland AFB, NM (United States))
Although high temperature, liquid metal heat pipe radiators have become a standard component on most high power space power system designs, there is no experimental data on the operation of these heat pipes in a zero gravity or micro-gravity environment. Experiments to benchmark the transient and steady state performance of prototypical heat pipe space radiator elements are in preparation for testing in low earth orbit. It is anticipated that these heat pipes will be tested aborad the Space Shuttle in 1995. Three heat pipes will be tested in a cargo bay Get Away Special (GAS) canister. The heat pipes are SST/potassium, each with a different wick structure; homogeneous, arterial, and annular gap, the heat pipes have been designed, fabricated, and ground tested. In this paper, the heat pipe designs are specified, and transient and steady-state ground test data are presented.
NASA Astrophysics Data System (ADS)
Jaenisch, G.-R.; Deresch, A.; Bellon, C.; Schumm, A.; Lucet-Sanchez, F.; Guerin, P.
The purpose of the 2014 WFNDEC RT benchmark study was to compare predictions of various models of radiographic techniques, in particular those that predict the contribution of scattered radiation. All calculations were carried out for homogenous materials and a mono-energetic X-ray point source in the energy range between 100 keV and 10 MeV. The calculations were to include the best physics approach available considering electron binding effects. Secondary effects like X-ray fluorescence and bremsstrahlung production were to be taken into account if possible. The problem to be considered had two parts. Part I examined the spectrum and the spatial distribution of radiation behind a single iron plate. Part II considered two equally sized plates, made of iron and aluminum respectively, only evaluating the spatial distribution. Here we present the results of above benchmark study, comparing them to MCNP as the assumed reference model. The possible origins of the observed deviations are discussed.
Heat pipe heat exchanger design considerations
K. T. Feldman; D. C. Lu
Typical heat pipe heat exchangers (HPHX) are described, along with their advantages, uses, and some problems in HPHX design, and a computer HPHX analysis program is discussed with required input data. The computer program is being developed for analysis of heat exchange performance by finned-tube HPHX and thread-puddle-artery heat pipes. Copper-water heat pipes and carbon steel-Dowtherm A heat pipes are
Interpolation and extrapolation problems of multivariate regression in analytical chemistry: benchmarking the robustness on near-infrared (NIR) spectroscopy data.
Balabin, Roman M; Smirnov, Sergey V
Modern analytical chemistry of industrial products is in need of rapid, robust, and cheap analytical methods to continuously monitor product quality parameters. For this reason, spectroscopic methods are often used to control the quality of industrial products in an on-line/in-line regime. Vibrational spectroscopy, including mid-infrared (MIR), Raman, and near-infrared (NIR), is one of the best ways to obtain information about the chemical structures and the quality coefficients of multicomponent mixtures. Together with chemometric algorithms and multivariate data analysis (MDA) methods, which were especially created for the analysis of complicated, noisy, and overlapping signals, NIR spectroscopy shows great results in terms of its accuracy, including classical prediction error, RMSEP. However, it is unclear whether the combined NIR + MDA methods are capable of dealing with much more complex interpolation or extrapolation problems that are inevitably present in real-world applications. In the current study, we try to make a rather general comparison of linear, such as partial least squares or projection to latent structures (PLS); "quasi-nonlinear", such as the polynomial version of PLS (Poly-PLS); and intrinsically non-linear, such as artificial neural networks (ANNs), support vector regression (SVR), and least-squares support vector machines (LS-SVM/LSSVM), regression methods in terms of their robustness. As a measure of robustness, we will try to estimate their accuracy when solving interpolation and extrapolation problems. Petroleum and biofuel (biodiesel) systems were chosen as representative examples of real-world samples. Six very different chemical systems that differed in complexity, composition, structure, and properties were studied; these systems were gasoline, ethanol-gasoline biofuel, diesel fuel, aromatic solutions of petroleum macromolecules, petroleum resins in benzene, and biodiesel. Eighteen different sample sets were used in total. General conclusions are made about the applicability of ANN- and SVM-based regression tools in the modern analytical chemistry. The effectiveness of different multivariate algorithms is different when going from classical accuracy to robustness. Neural networks, which are capable of producing very accurate results with respect to classical RMSEP, are not able to solve interpolation problems or, especially, extrapolation problems. The chemometric methods that are based on the support vector machine (SVM) ideology are capable of solving both classical regression and interpolation/extrapolation tasks. PMID:22337290
NASA Technical Reports Server (NTRS)
Burns & McDonnell provide architectural and engineering services in planning, design and construction of a wide range of projects all over the world. In design analysis, company regularly uses COSMIC computer programs. In computer testing piping design of a power plant, company uses Pipe Flexibility Analysis Program (MEL-21) to analyze stresses due to weight, temperature, and pressure found in proposed piping systems. Individual flow rates are put into the computer, then computer calculates the pressure drop existing across each component; if needed, design corrections or adjustments can be made and rechecked.
Unstructured Adaptive (UA) NAS Parallel Benchmark. Version 1.0
NASA Technical Reports Server (NTRS)
Feng, Huiyu; VanderWijngaart, Rob; Biswas, Rupak; Mavriplis, Catherine
We present a complete specification of a new benchmark for measuring the performance of modern computer systems when solving scientific problems featuring irregular, dynamic memory accesses. It complements the existing NAS Parallel Benchmark suite. The benchmark involves the solution of a stylized heat transfer problem in a cubic domain, discretized on an adaptively refined, unstructured mesh.
The DARPA Dynamic Programming Benchmark on a Reconfigurable Computer
Luis E. Cordova; Duncan A. Buell; Sreesa Akella
The Defense Advanced Research Projects Agency (DARPA) has released high productivity computing systems (HPCS) benchmarks as specifications of performance required to solve important problems. This work reports on the design, implementation, and benchmarking of the benchmark number two, dynamic programming (DP), as developed in a general purpose reconfigurable computer. DP methods are used to solve DNA sequencing problems. DP has
Light pipes for LED measurements
NASA Technical Reports Server (NTRS)
Floyd, S. R.; Thomas, E. F., Jr.
Light pipe directly couples LED optical output to single detector. Small area detector measures total optical output of diode. Technique eliminates thermal measurement problems and channels optical output to remote detector.
Emerging heat pipe applications
A. Basuilis; D. J. Formiller
The article discusses the application of heat pipes in various industrial, military, and space projects. Several types of heat pipes are described, including simple cylindrical heat pipes, switching heat pipes, thermal diodes, variable conductance heat pipes, and vapor chambers. Potential future applications of heat pipes are identified in the fields of electronics, spacecraft thermal control, heat pipe recovery systems, and
CFD validation in OECD/NEA t-junction benchmark.
Obabko, A. V.; Fischer, P. F.; Tautges, T. J.; Karabasov, S.; Goloviznin, V. M.; Zaytsev, M. A.; Chudanov, V. V.; Pervichko, V. A.; Aksenova, A. E. (Mathematics and Computer Science); (Cambridge Univ.); (Moscow Institute of Nuclar Energy Safety)
When streams of rapidly moving flow merge in a T-junction, the potential arises for large oscillations at the scale of the diameter, D, with a period scaling as O(D/U), where U is the characteristic flow velocity. If the streams are of different temperatures, the oscillations result in experimental fluctuations (thermal striping) at the pipe wall in the outlet branch that can accelerate thermal-mechanical fatigue and ultimately cause pipe failure. The importance of this phenomenon has prompted the nuclear energy modeling and simulation community to establish a benchmark to test the ability of computational fluid dynamics (CFD) codes to predict thermal striping. The benchmark is based on thermal and velocity data measured in an experiment designed specifically for this purpose. Thermal striping is intrinsically unsteady and hence not accessible to steady state simulation approaches such as steady state Reynolds-averaged Navier-Stokes (RANS) models.1 Consequently, one must consider either unsteady RANS or large eddy simulation (LES). This report compares the results for three LES codes: Nek5000, developed at Argonne National Laboratory (USA), and Cabaret and Conv3D, developed at the Moscow Institute of Nuclear Energy Safety at (IBRAE) in Russia. Nek5000 is based on the spectral element method (SEM), which is a high-order weighted residual technique that combines the geometric flexibility of the finite element method (FEM) with the tensor-product efficiencies of spectral methods. Cabaret is a 'compact accurately boundary-adjusting high-resolution technique' for fluid dynamics simulation. The method is second-order accurate on nonuniform grids in space and time, and has a small dispersion error and computational stencil defined within one space-time cell. The scheme is equipped with a conservative nonlinear correction procedure based on the maximum principle. CONV3D is based on the immersed boundary method and is validated on a wide set of the experimental and benchmark data. The numerical scheme has a very small scheme diffusion and is the second and the first order accurate in space and time, correspondingly. We compare and contrast simulation results for three computational fluid dynamics codes CABARET, Conv3D, and Nek5000 for the T-junction thermal striping problem that was the focus of a recent OECD/NEA blind benchmark. The corresponding codes utilize finite-difference implicit large eddy simulation (ILES), finite-volume LES on fully staggered grids, and an LES spectral element method (SEM), respectively. The simulations results are in a good agreement with experimenatl data. We present results from a study of sensitivity to computational mesh and time integration interval, and discuss the next steps in the simulation of this problem.
Drowning - a scientometric analysis and data acquisition of a constant global problem employing density equalizing mapping and scientometric benchmarking procedures
Background Drowning is a constant global problem which claims approximately half a million victims worldwide each year, whereas the number of near-drowning victims is considerably higher. Public health strategies to reduce the burden of death are still limited. While research activities in the subject drowning grow constantly, yet there is no scientometric evaluation of the existing literature at the present time. Methods The current study uses classical bibliometric tools and visualizing techniques such as density equalizing mapping to analyse and evaluate the scientific research in the field of drowning. The interpretation of the achieved results is also implemented in the context of the data collection of the WHO. Results All studies related to drowning and listed in the ISI-Web of Science database since 1900 were identified using the search term "drowning". Implementing bibliometric methods, a constant increase in quantitative markers such as number of publications per state, publication language or collaborations as well as qualitative markers such as citations were observed for research in the field of drowning. The combination with density equalizing mapping exposed different global patterns for research productivity and the total number of drowning deaths and drowning rates respectively. Chart techniques were used to illustrate bi- and multilateral research cooperation. Conclusions The present study provides the first scientometric approach that visualizes research activity on the subject of drowning. It can be assumed that the scientific approach to this topic will achieve even greater dimensions because of its continuing actuality. PMID:21999813
High temperature loop heat pipes
Anderson, W.G.; Bland, J.J. [Thermacore, Inc., Lancaster, PA (United States); Fershtater, Y.; Goncharov, K.A.; Nikitkin, M. [TAIS, Inc., Moscow (Russian Federation); Juhasz, A. [NASA Lewis Research Center, Cleveland, OH (United States)
Advantages of loop heat pipes over conventional heat pipes include self-priming during start-up, improved tolerance for noncondensible gas, and ability for ground testing in any orientation. The applications for high temperature, alkali-metal working fluid loop heat pipes include space radiators, and bimodal systems. A high temperature loop heat pipe was fabricated and tested at 850 K, using cesium as the working fluid. Previous loop heat pipes were tested with ambient temperature working fluids at temperatures below about 450 K. The loop heat pipe had a titanium envelope, and a titanium aluminide wick. The maximum cesium loop heat pipe power was only about 600 watts, which was lower the predicted 1,000 W power. The power limitation may be due to a wettability problem with the cesium not completely wetting the titanium aluminide wick. This would reduce the pumping capability of the wick, and the maximum power that the heat pipe could carry. This problem could be solved by using a refractory metal powder wick, since the alkali metals are known to wet refractory metal wicks.
The dynamics of mercury flow in a curved pipe
McDonald, Kirk
The dynamics of mercury flow in a curved pipe Yan Zhan Foluso LadeindeFoluso Ladeinde 11 of the problem Pi t ff t� Pipe curvature effect � Laminar flow in the mercury supply pipe l i� Conclusion #12 Project. � Target delivery systems involves pipe curvature, axially- d d t di l di t d l l th tdependent
Radiation Detection Computational Benchmark Scenarios
Shaver, Mark W.; Casella, Andrew M.; Wittman, Richard S.; McDonald, Ben S.
Modeling forms an important component of radiation detection development, allowing for testing of new detector designs, evaluation of existing equipment against a wide variety of potential threat sources, and assessing operation performance of radiation detection systems. This can, however, result in large and complex scenarios which are time consuming to model. A variety of approaches to radiation transport modeling exist with complementary strengths and weaknesses for different problems. This variety of approaches, and the development of promising new tools (such as ORNL�s ADVANTG) which combine benefits of multiple approaches, illustrates the need for a means of evaluating or comparing different techniques for radiation detection problems. This report presents a set of 9 benchmark problems for comparing different types of radiation transport calculations, identifying appropriate tools for classes of problems, and testing and guiding the development of new methods. The benchmarks were drawn primarily from existing or previous calculations with a preference for scenarios which include experimental data, or otherwise have results with a high level of confidence, are non-sensitive, and represent problem sets of interest to NA-22. From a technical perspective, the benchmarks were chosen to span a range of difficulty and to include gamma transport, neutron transport, or both and represent different important physical processes and a range of sensitivity to angular or energy fidelity. Following benchmark identification, existing information about geometry, measurements, and previous calculations were assembled. Monte Carlo results (MCNP decks) were reviewed or created and re-run in order to attain accurate computational times and to verify agreement with experimental data, when present. Benchmark information was then conveyed to ORNL in order to guide testing and development of hybrid calculations. The results of those ADVANTG calculations were then sent to PNNL for compilation. This is a report describing the details of the selected Benchmarks and results from various transport codes.
Romain Berrendonner; J�r�me Guitton
This article presents ERB, the ESA Ravenscar Benchmark. ERB aims at providing a synthetic benchmark comparing the efficiency of various Ada Ravenscar implementations and the RTEMS C implementation featuring the na- tive threading model. ERB is original compared to existing Ada benchmarks, such as the ACES or the PIWG, not only because it is the first Ada Ravenscar benchmark, but
Optimal portfolio strategies benchmarking the stock market
A. Gabih; W. Grecksch; M. Richter; R. Wunderlich
The paper investigates the impact of adding a shortfall risk constraint to the problem of a portfolio manager who wishes to maximize his utility from the portfolios terminal wealth. Since portfolio managers are often evaluated relative to benchmarks which depend on the stock market we capture risk management considerations by allowing a prespecified risk of falling short such a benchmark.
NASA Technical Reports Server (NTRS)
In Stennis Space Center's Component Test Facility, piping lines carry rocket propellants and high pressure cryogenic fuels. When the lines are chilled to a pretest temperature of 400 degrees below zero, ordinary piping connectors can leak. Under contract to Stennis, Reflange, Inc. developed the T-Con connector, which included a secondary seal that tolerates severe temperature change. Because of the limited need for the large and expensive T-Con product, Reflange also developed the less costly E-Con, a smaller more compact design with the same technical advantages as the T-Con.
Development of a magnetic coating for gas pipe detection. Final report, May 1987June 1988
The inability to accurately locate plastic gas pipe after it is buried has been a troublesome problem since plastic pipe began being used for natural gas distribution. Electromagnetic pipe locaters have been available to the gas industry for decades. However, this technology cannot locate plastic pipe without the use of a metallic wire or tape buried with the pipe. To
Factory Flow Benchmarking Report
Shields, Thomas J.
LAI benchmarked representative part fabrications and some assembly operations within its member companies of the defense aircraft industry. This paper reports the results of this benchmarking effort. In addition, this ...
NASTRAN analysis of an air storage piping system
NASA Technical Reports Server (NTRS)
Young, C. P., Jr.; Gerringer, A. H.; Faison, R. W.
The application of NASTRAN to a complex piping design evaluation problem is summarized. Emphasis is placed on structural modeling aspects, problems encountered in modeling and analyzing curved pipe sections, principal results, and relative merits of using NASTRAN as a pipe analysis and design tool. In addition, the piping and manifolding system was analyzed with SNAP (Structural Network Analysis Program). The parallel SNAP study provides a basis for limited comparisons between NASTRAN and SNAP as to solution agreement and computer execution time and costs.
Enchancement of heat pipes with ion-drag pumps�
Babin, Bruce Russell
transfer occurring at the evaporator This problem occurs on all types of heat pipes, from the large monogroove heat pipes used on the space station (Alario et al. , 1981) to the tiny micro heat pipes used in electronic cooling (Babin et al. , 1989). Many... have problems associated with vibrations or size limitations. There is another pumping mechanism that has not been previously investigated for heat pipe applications: electrohydrodynamic pumping. Electrohydrodynamic (EHD) pumping is produced...
Chun hua Tian; Jing Xiao; Jin Huang; Felipe Albertao
Preventa tive pipe maintenance is a key activity in pipe asset management. Central to such activity is a precise pipe failure (burstJIeakage) prediction. Here a statistical pipe failure prediction approach is proposed based on the massive data including pipe physical property, environmental factor, operational condition, historical failure records, and etc. Considering the biased training cases, survival analysis model is adopted
NASA Technical Reports Server (NTRS)
A bibliography of heat pipe technology to provide a summary of research projects conducted on heat pipes is presented. The subjects duscussed are: (1) heat pipe applications, (2) heat pipe theory, (3) design and fabrication, (4) testing and operation, (5) subject and author index, and (6) heat pipe related patents.
A steady state analysis code for prediction of behavior in loop heat pipes�
Hamm, Trenton Allen
The purpose of this work is to prepare an analysis raphics. code for the prediction of Loop Heat Pipe (LHP) behavior in steady-state operation. The FORTRAN program is then benchmarked with experimental data obtained in two ...
Hydrological connectivity of soil pipes
NASA Astrophysics Data System (ADS)
Holden, J.
Natural soil pipes are common in many parts of the world and particularly in blanket peat uplands yet there are problems in finding and defining soil pipe networks which are often located deep within the peat. Pipeflow can contribute a large proportion of runoff to the river systems in these upland environments and may significantly influence catchment sediment and solute yield. Ground penetrating radar (GPR) technology has recently been developed for non-destructive identification and mapping of soil pipes in peat catchments. While GPR can identify subsurface cavities, it cannot alone determine hydrological connectivity between one cavity and another. This poster presents results from an experiment to test the ability of GPR to establish hydrological connectivity between pipes through use of a tracer solution. Tracers such as sodium chloride were injected at a constant rate into an open pipe cavity. The GPR was moved across the test area downslope. The resultant radargrams were analysed and significantly increased reflectance was observed from a selection of cavities downslope. It was thus possible to determine hydrological connectivity of soil pipes within a dense pipe network across a hillslope without ground disturbance. In addition, tracers were added to the peat surface upslope of known pipe networks. It was possible to then trace the movement of water across and through the hillslope by using GPR to establish the connectivity of a range of flowpaths. Often pipe networks were supplied with water from overland flow entering through cracks and openings where the soil pipe was near the peat surface. Downslope, pipeflow contributed not only directly to streamflow but also to overland flow and near-surface throughflow on the hillslope. The same water that was within a pipe network at four metres depth could become near-surface throughflow outside of the pipe network a few metres down slope. These data allow the first three-dimensional picture of subsurface hydrological pathways to be developed for blanket peat catchments. The improved understanding of flowpath connectivity will be important for understanding solutional and particulate denudation and hydrological and geomorphological model development.
Heat Pipe Technology for Refrigeration and Cooling
H. F. Smirnov
\\u000a A main goal of this review was an exchange of the essential ideas and practical problems of heat pipe technology use for refrigeration\\u000a and cooling, with respect to the following most perspective spotlights:\\u000a \\u000a \\u000a \\u000a 1.�\\u000a \\u000a Heat pipes and especially loop heat pipes application as a safe external or internal thermal link.\\u000a \\u000a \\u000a \\u000a 2.�\\u000a \\u000a Heat pipe technology as a base for refrigerating heat
J. Ortensi; M.A. Pope; G. Strydom; R.S. Sen; M.D. DeHart; H.D. Gougar; C. Ellis; A. Baxter; V. Seker; T.J. Downar; K. Vierow; K. Ivanov
The Prismatic Modular Reactor (PMR) is one of the High Temperature Reactor (HTR) design concepts that have existed for some time. Several prismatic units have operated in the world (DRAGON, Fort St. Vrain, Peach Bottom) and one unit is still in operation (HTTR). The deterministic neutronics and thermal-fluids transient analysis tools and methods currently available for the design and analysis of PMRs have lagged behind the state of the art compared to LWR reactor technologies. This has motivated the development of more accurate and efficient tools for the design and safety evaluations of the PMR. In addition to the work invested in new methods, it is essential to develop appropriate benchmarks to verify and validate the new methods in computer codes. The purpose of this benchmark is to establish a well-defined problem, based on a common given set of data, to compare methods and tools in core simulation and thermal hydraulics analysis with a specific focus on transient events. The benchmark-working group is currently seeking OECD/NEA sponsorship. This benchmark is being pursued and is heavily based on the success of the PBMR-400 exercise.
Mixed-Oxide (MOX) Fuel Performance Benchmarks
Ott, Larry J [ORNL; Tverberg, Terje [OECD Halden Reactor Project; Sartori, Enrico [ORNL
Within the framework of the OECD/NEA Expert Group on Reactor-based Plutonium disposition (TFRPD), a fuel modeling code benchmarks for MOX fuel was initiated. This paper summarizes the calculation results provided by the contributors for the first two fuel performance benchmark problems. A limited sensitivity study of the effect of the rod power uncertainty on code predictions of fuel centerline temperature and fuel pin pressure also was performed and is included in the paper.
On the Radiation of Sound from an Unflanged Circular Pipe
Harold Levine; Julian Schwinger
A rigorous and explicit solution is obtained for the problem of sound radiation from an unflanged circular pipe, assuming axially symmetric excitation. The solution is valid throughout the wave-length range of dominant mode (plane wave) propagation in the pipe. The reflection coefficient for the velocity potential within the pipe and the power-gain function, embodying the characteristics of the radiation pattern,
Chen, Wei
GAPRUS - GENETIC ALGORITHMS BASED PIPE ROUTING USING TESSELLATED OBJECTS Sunand Sandurkar Software problems involving 3D freeform obstacles is demonstrated. Key words: Pipe Routing, Genetic Algorithms of CAD model as a connected array of triangles (tessellated format) GAPRUS Genetic Algorithm based Pipe
Applications of heat pipes to cool PWBS and hybrid microcircuits
NASA Technical Reports Server (NTRS)
Sekhon, K. S.
Some of the advanced thermal management techniques used to reduce operating junction temperature under extreme environmental temperature conditions are discussed. Heat pipes in actual electronic packaging applications, and those under development, are discussed. Performance characteristics of heat pipes are given, and examples are described of how thermal problems in electronic packaging are solved through the use of heat pipes.
The goals of this project are to develop and apply a methodology for benchmarking curricula in sustainability engineering and to identify individuals active in sustainability engineering education. ...
Benchmarking short sequence mapping tools
Background The development of next-generation sequencing instruments has led to the generation of millions of short sequences in a single run. The process of aligning these reads to a reference genome is time consuming and demands the development of fast and accurate alignment tools. However, the current proposed tools make different compromises between the accuracy and the speed of mapping. Moreover, many important aspects are overlooked while comparing the performance of a newly developed tool to the state of the art. Therefore, there is a need for an objective evaluation method that covers all the aspects. In this work, we introduce a benchmarking suite to extensively analyze sequencing tools with respect to various aspects and provide an objective comparison. Results We applied our benchmarking tests on 9 well known mapping tools, namely, Bowtie, Bowtie2, BWA, SOAP2, MAQ, RMAP, GSNAP, Novoalign, and mrsFAST (mrFAST) using synthetic data and real RNA-Seq data. MAQ and RMAP are based on building hash tables for the reads, whereas the remaining tools are based on indexing the reference genome. The benchmarking tests reveal the strengths and weaknesses of each tool. The results show that no single tool outperforms all others in all metrics. However, Bowtie maintained the best throughput for most of the tests while BWA performed better for longer read lengths. The benchmarking tests are not restricted to the mentioned tools and can be further applied to others. Conclusion The mapping process is still a hard problem that is affected by many factors. In this work, we provided a benchmarking suite that reveals and evaluates the different factors affecting the mapping process. Still, there is no tool that outperforms all of the others in all the tests. Therefore, the end user should clearly specify his needs in order to choose the tool that provides the best results. PMID:23758764
Rehabilitating underground pipes
Sorrell, P. [Insituform Technologies, Inc., Memphis, TN (United States)
Nearly 500,000 miles of industrial pipeline in the US are almost three times older than their expected usefulness. And aging pipes that are improperly maintained can cause a variety of environmental problems. It is essential for facilities to have a system of planned maintenance procedures to prevent structural failures related to inflow/infiltration and exfiltration. Trenchless repair methods, often referred to as pipeline rehabilitation, require the plant engineer to consider a range of activities, including demand projection, system performance assessment, investigation, evaluation of defects and deficiencies, remedial options, and implementation. Two methods of pipeline rehabilitation, slip lining and cured-in-place, are described.
Pipes and pipelines are being used for an ever widening range of materials, for increasing flows and in harsher applications. There is also more legal and social pressure to reduce the hazards associated with handling materials in pipes. All of this increases the demand for improved pipe reliability. Two of the major preventable causes of pipe failure are corrosion and
Magnetohydrodynamic pipe flow. Part 1
Richard R. Gold
The solution is obtained to the problem of the steady onedimensional ; flow of an incompressible, viscous, electrically fluid through a circular pipe in ; the presence of an applied (transverse) uniform magnetic field. A no-slip ; condition on the velocity is assumed at the nonconducting wall. The solution is ; exact and thus valid for all values of the
IU parallel processing benchmark
Charles Weems; Edward Riseman; Allen Hanson; Azriel Rosenfeld
A benchmark is presented that was designed to evaluate the merits of various parallel architectures as applied to image understanding (IU). This benchmark exercise addresses the issue of system performance on an integrated set of tasks, where the task interactions that are typical of complex vision application are present. The goal of this exercise is to gain a better understanding
Thermal Performance Benchmarking (Presentation)
Moreno, G.
This project will benchmark the thermal characteristics of automotive power electronics and electric motor thermal management systems. Recent vehicle systems will be benchmarked to establish baseline metrics, evaluate advantages and disadvantages of different thermal management systems, and identify areas of improvement to advance the state-of-the-art.
USGS Yosemite Benchmark Streamgage
In this image, the USGS Hydrologic Benchmark Streamgage on the Merced River in Yosemite Valley can be seen. Hydrologic Benchmark streamgages are those at which no human development exists upstream of the streamgage. This streamgage is a cooperation between the National Park Service, National Oceanic...
EPA has announced the latest update to the Benchmark Dose Software (BMDS) tool which is used to facilitate the application of benchmark dose (BMD) methods to EPA hazardous pollutant risk assessments. This latest version (1.4.1b) contains seventeen (17) different models that ar...
Epilepsy Research Benchmarks Progress Report
Epilepsy Research Benchmarks Progress Report 2007 � 2012 #12;i Epilepsy Research Benchmarks .................................................................................................................................................................................... 1 Benchmarks Area I - Prevent epilepsy and its progression.......................................................................................................................2 A. Identify as yet unrecognized causes of epilepsy (e.g., genetic, autoimmune and infectious
Corrosion problem solutions for pipe and equipment during manufacture, fabrication, and storage using vapor corrosion inhibitors (VCI`s) and dry air
Gelner, L. [Protec, Inc., North Hampton, NH (United States)
This paper presents current technology and use of environmentally friendly, cost effective materials and techniques for pipe and equipment preservation. This includes the use of Temporary Inhibitor Coatings (TIC), Vapor Corrosion Inhibitors (VCI), and dehumidified air (DH). Materials are described in detail, and applications of each are discussed.
VITS Test Suit: A Micro-benchmark for Evaluating Performance Isolation of Virtualization Systems
Pingpeng Yuan; Chong Ding; Long Cheng; Shengli Li; Hai Jin; Wenzhi Cao
Virtualization technology improves the resource utilization, but also raises the probability of resource contention. Thus, it arises one problem, namely how about performance isolation among VMs. To answer the question, benchmarks are highly required to evaluate performance isolation. However, few benchmarks to give solutions to the problem are available. Especially, there does not exist a micro-benchmark to measure how the
Anderson, M.J.; Hyde, L.L.; Wagner, S.E.; Severud, L.K.
Thin wall large diameter piping for breeder reactor plants can be subjected to significant thermal shocks during reactor scrams and other upset events. On the Fast Flux Test Facility, the addition of thick clamps directly on the piping was undesired because the differential metal temperatures between the pipe wall and the clamp could have significantly reduced the pipe thermal fatigue life cycle capabilities. Accordingly, an insulated pipe clamp design concept was developed. The design considerations and methods along with the development tests are presented. Special considerations to guard against adverse cracking of the insulation material, to maintain the clamp-pipe stiffness desired during a seismic event, to minimize clamp restraint on the pipe during normal pipe heatup, and to resist clamp rotation or spinning on the pipe are emphasized.
Person, Abraham (Los Alamitos, CA)
In an ocean thermal energy conversion facility, a cold water riser pipe is releasably supported at its upper end by the hull of the floating facility. The pipe is substantially vertical and has its lower end far below the hull above the ocean floor. The pipe is defined essentially entirely of a material which has a modulus of elasticity substantially less than that of steel, e.g., high density polyethylene, so that the pipe is flexible and compliant to rather than resistant to applied bending moments. The position of the lower end of the pipe relative to the hull is stabilized by a weight suspended below the lower end of the pipe on a flexible line. The pipe, apart from the weight, is positively buoyant. If support of the upper end of the pipe is released, the pipe sinks to the ocean floor, but is not damaged as the length of the line between the pipe and the weight is sufficient to allow the buoyant pipe to come to a stop within the line length after the weight contacts the ocean floor, and thereafter to float submerged above the ocean floor while moored to the ocean floor by the weight. The upper end of the pipe, while supported by the hull, communicates to a sump in the hull in which the water level is maintained below the ambient water level. The sump volume is sufficient to keep the pipe full during heaving of the hull, thereby preventing collapse of the pipe.
Stiffness-Mass Ratios Method for a baseline determination and damage assessment of a benchmark structure�
Rocha, Ramses Rodriguez
A new method based on ratios between stiffness and mass values from the eigenvalue problem is introduced and applied to the benchmark structure to obtain baseline modal parameters utilizing damaged state information of the structure. The benchmark...
Using Flexible Pipe (poly-pipe) with Surface Irrigation�
Peries, Xavier; Enciso, Juan
Aimed at farmers and irrigators who want to irrigate their crops using flexible plastic pipes (commonly called "poly-pipe), this publication highlights (1) advantages of using poly-pipe, (2) factors to consider in selecting such pipe, and (3...
Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey
INTERIOR VIEW WITH PIPE CASTING MACHINE CASTING A 24' PIPE AND OPERATOR JOHNNY NIXON. - United States Pipe & Foundry Company Plant, Pipe Casting & Testing Area, 2023 St. Louis Avenue at I-20/59, Bessemer, Jefferson County, AL
Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey
INTERIOR VIEW WITH PIPE CASTING MACHINE EXTRUDING A 24' PIPE AND OPERATOR JOHNNY NIXON. - United States Pipe & Foundry Company Plant, Pipe Casting & Testing Area, 2023 St. Louis Avenue at I-20/59, Bessemer, Jefferson County, AL
Translational benchmark risk analysis
Piegorsch, Walter W.
Translational development � in the sense of translating a mature methodology from one area of application to another, evolving area � is discussed for the use of benchmark doses in quantitative risk assessment. Illustrations are presented with traditional applications of the benchmark paradigm in biology and toxicology, and also with risk endpoints that differ from traditional toxicological archetypes. It is seen that the benchmark approach can apply to a diverse spectrum of risk management settings. This suggests a promising future for this important risk-analytic tool. Extensions of the method to a wider variety of applications represent a significant opportunity for enhancing environmental, biomedical, industrial, and socio-economic risk assessments. PMID:20953283
A benchmark for subduction zone modeling
NASA Astrophysics Data System (ADS)
van Keken, P.; King, S.; Peacock, S.
Our understanding of subduction zones hinges critically on the ability to discern its thermal structure and dynamics. Computational modeling has become an essential complementary approach to observational and experimental studies. The accurate modeling of subduction zones is challenging due to the unique geometry, complicated rheological description and influence of fluid and melt formation. The complicated physics causes problems for the accurate numerical solution of the governing equations. As a consequence it is essential for the subduction zone community to be able to evaluate the ability and limitations of various modeling approaches. The participants of a workshop on the modeling of subduction zones, held at the University of Michigan at Ann Arbor, MI, USA in 2002, formulated a number of case studies to be developed into a benchmark similar to previous mantle convection benchmarks (Blankenbach et al., 1989; Busse et al., 1991; Van Keken et al., 1997). Our initial benchmark focuses on the dynamics of the mantle wedge and investigates three different rheologies: constant viscosity, diffusion creep, and dislocation creep. In addition we investigate the ability of codes to accurate model dynamic pressure and advection dominated flows. Proceedings of the workshop and the formulation of the benchmark are available at www.geo.lsa.umich.edu/~keken/subduction02.html We strongly encourage interested research groups to participate in this benchmark. At Nice 2003 we will provide an update and first set of benchmark results. Interested researchers are encouraged to contact one of the authors for further details.
Benchmark Solutions for Computational Aeroacoustics (CAA) Code Validation
NASA Technical Reports Server (NTRS)
Scott, James R.
NASA has conducted a series of Computational Aeroacoustics (CAA) Workshops on Benchmark Problems to develop a set of realistic CAA problems that can be used for code validation. In the Third (1999) and Fourth (2003) Workshops, the single airfoil gust response problem, with real geometry effects, was included as one of the benchmark problems. Respondents were asked to calculate the airfoil RMS pressure and far-field acoustic intensity for different airfoil geometries and a wide range of gust frequencies. This paper presents the validated that have been obtained to the benchmark problem, and in addition, compares them with classical flat plate results. It is seen that airfoil geometry has a strong effect on the airfoil unsteady pressure, and a significant effect on the far-field acoustic intensity. Those parts of the benchmark problem that have not yet been adequately solved are identified and presented as a challenge to the CAA research community.
Benchmark neutron porosity log calculations
Little, R.C.; Michael, M.; Verghese, K.; Gardner, R.P.
Calculations have been made for a benchmark neutron porosity log problem with the general purpose Monte Carlo code MCNP and the specific purpose Monte Carlo code McDNL. For accuracy and timing comparison purposes the CRAY XMP and MicroVax II computers have been used with these codes. The CRAY has been used for an analog version of the MCNP code while the MicroVax II has been used for the optimized variance reduction versions of both codes. Results indicate that the two codes give the same results within calculated standard deviations. Comparisons are given and discussed for accuracy (precision) and computation times for the two codes.
Schilling, R. E.
Pipe Insulation Economies is a computer program written in IBM basic to simplify the economic insulation thickness for an insulated pipe. Many articles have been written on this subject, from simple nomographs to a small book written in 1976...
NASA Technical Reports Server (NTRS)
Howard, F. S.
Smaller concentric pipe is welded to main pipe beginning above bottom of isolation valve and terminating in storage tank at top. There is continuous circulation of fluid which maintains fluid temperature below boiling temperature of liquid oxygen.
The Design of a Scalable, Fixed-Time Computer Benchmark
John L. Gustafson; Diane T. Rover; Stephen Elbert; Michael Carter
By using the principle of fixed-time benchmarking, it is possible to compare a wide range of computers, from a small personal computer to the most powerful parallel supercomputer, on a single scale. Fixed-time benchmarks promise greater longevity than those based on a particular problem size and are more appropriate for \\
Full sphere hydrodynamic and dynamo benchmarks
NASA Astrophysics Data System (ADS)
Marti, P.; Schaeffer, N.; Hollerbach, R.; C�bron, D.; Nore, C.; Luddens, F.; Guermond, J.-L.; Aubert, J.; Takehiro, S.; Sasaki, Y.; Hayashi, Y.-Y.; Simitev, R.; Busse, F.; Vantieghem, S.; Jackson, A.
Convection in planetary cores can generate fluid flow and magnetic fields, and a number of sophisticated codes exist to simulate the dynamic behaviour of such systems. We report on the first community activity to compare numerical results of computer codes designed to calculate fluid flow within a whole sphere. The flows are incompressible and rapidly rotating and the forcing of the flow is either due to thermal convection or due to moving boundaries. All problems defined have solutions that allow easy comparison, since they are either steady, slowly drifting or perfectly periodic. The first two benchmarks are defined based on uniform internal heating within the sphere under the Boussinesq approximation with boundary conditions that are uniform in temperature and stress-free for the flow. Benchmark 1 is purely hydrodynamic, and has a drifting solution. Benchmark 2 is a magnetohydrodynamic benchmark that can generate oscillatory, purely periodic, flows and magnetic fields. In contrast, Benchmark 3 is a hydrodynamic rotating bubble benchmark using no slip boundary conditions that has a stationary solution. Results from a variety of types of code are reported, including codes that are fully spectral (based on spherical harmonic expansions in angular coordinates and polynomial expansions in radius), mixed spectral and finite difference, finite volume, finite element and also a mixed Fourier-finite element code. There is good agreement between codes. It is found that in Benchmarks 1 and 2, the approximation of a whole sphere problem by a domain that is a spherical shell (a sphere possessing an inner core) does not represent an adequate approximation to the system, since the results differ from whole sphere results.
This book provides the information required to design and prepare construction drawings, and to install, inspect, test, and commission buried piping. Both pressure and gravity piping are covered, including water, steam, gases, and sewers. Directed primarily toward underground industrial piping systems, this is a succinct, well-organized compilation of practical knowledge. Checklists, examples, tables, charts, nomographs, short cuts, and helpful hints
NASA Astrophysics Data System (ADS)
Merrigan, M.
Progress in developing ceramic heat pipe recuperators for recovering heat from industrial processing furnaces is reported. Information is included on the design, materials procurement, fabrication, materials testing, performance testing, performance and cost of ceramic heat pipes, especially tungsten-coated silicon carbide and Sic-W-Mo heat pipes.
M. Merrigan
Progress in developing ceramic heat pipe recuperators for recovering heat from industrial processing furnaces is reported. Information is included on the design, materials procurement, fabrication, materials testing, performance testing, performance and cost of ceramic heat pipes, especially tungsten-coated silicon carbide and Sic-W-Mo heat pipes.
M. A. Merrigan
Critical high temperature, high power applications in space nuclear power designs are near the current state of the art of heat pipe technology in terms of power density, operating temperature, and lifetime. Recent heat pipe development work at Los Alamos National Laboratory involved performance testing of typical space reactor heat pipe designs to power levels in excess of 19 kW\\/cm(2)
NASA Technical Reports Server (NTRS)
The array of tanks, pipes and valves in the photo below is a petroleum tank farm in Georgia, part of a petrochemical pipe line system that moves refined petroleum products from Texas and Louisiana to the mid-Eastern seaboard. The same pipes handle a number of different products, such as gasoline, kerosene, jet fuel or fuel oil. The fluids are temporarily stored in tanks, pumped into the pipes in turn and routed to other way stations along the pipe line. The complex job of controlling, measuring and monitoring fuel flow is accomplished automatically by a computerized control and communications system which incorporates multiple space technologies.
Pudar, Ranko S.; Liggett, James A.
Leak detection in water-distribution systems can be accomplished by solving an inverse problem using measurements of pressure and/or flow. The problem is formulated with equivalent orifice areas of possible leaks as the unknowns. Minimization of the difference between measured and calculated heads produces a solution for the areas. The quality of the result depends on number and location of the measurements. A sensitivity matrix is key to deciding where to make measurements. Both location and magnitude of leaks are sensitive to the quantity and quality of pressure measurements and to how well the pipe friction parameters are known. The overdetermined problem (more measurements than suspected leaks) gives the best results, but some information can be derived from the underdetermined problem. The variance of leak areas, based on the quality of system characteristics and pressure data, indicates the likely accuracy of the results. The method will not substitute for more traditional leak surveys but can serve as a guide and supplement.
Storage-Intensive Supercomputing Benchmark Study
Cohen, J; Dossa, D; Gokhale, M; Hysom, D; May, J; Pearce, R; Yoo, A
Critical data science applications requiring frequent access to storage perform poorly on today's computing architectures. This project addresses efficient computation of data-intensive problems in national security and basic science by exploring, advancing, and applying a new form of computing called storage-intensive supercomputing (SISC). Our goal is to enable applications that simply cannot run on current systems, and, for a broad range of data-intensive problems, to deliver an order of magnitude improvement in price/performance over today's data-intensive architectures. This technical report documents much of the work done under LDRD 07-ERD-063 Storage Intensive Supercomputing during the period 05/07-09/07. The following chapters describe: (1) a new file I/O monitoring tool iotrace developed to capture the dynamic I/O profiles of Linux processes; (2) an out-of-core graph benchmark for level-set expansion of scale-free graphs; (3) an entity extraction benchmark consisting of a pipeline of eight components; and (4) an image resampling benchmark drawn from the SWarp program in the LSST data processing pipeline. The performance of the graph and entity extraction benchmarks was measured in three different scenarios: data sets residing on the NFS file server and accessed over the network; data sets stored on local disk; and data sets stored on the Fusion I/O parallel NAND Flash array. The image resampling benchmark compared performance of software-only to GPU-accelerated. In addition to the work reported here, an additional text processing application was developed that used an FPGA to accelerate n-gram profiling for language classification. The n-gram application will be presented at SC07 at the High Performance Reconfigurable Computing Technologies and Applications Workshop. The graph and entity extraction benchmarks were run on a Supermicro server housing the NAND Flash 40GB parallel disk array, the Fusion-io. The Fusion system specs are as follows: SuperMicro X7DBE Xeon Dual Socket Blackford Server Motherboard; 2 Intel Xeon Dual-Core 2.66 GHz processors; 1 GB DDR2 PC2-5300 RAM (2 x 512); 80GB Hard Drive (Seagate SATA II Barracuda). The Fusion board is presently capable of 4X in a PCIe slot. The image resampling benchmark was run on a dual Xeon workstation with NVIDIA graphics card (see Chapter 5 for full specification). An XtremeData Opteron+FPGA was used for the language classification application. We observed that these benchmarks are not uniformly I/O intensive. The only benchmark that showed greater that 50% of the time in I/O was the graph algorithm when it accessed data files over NFS. When local disk was used, the graph benchmark spent at most 40% of its time in I/O. The other benchmarks were CPU dominated. The image resampling benchmark and language classification showed order of magnitude speedup over software by using co-processor technology to offload the CPU-intensive kernels. Our experiments to date suggest that emerging hardware technologies offer significant benefit to boosting the performance of data-intensive algorithms. Using GPU and FPGA co-processors, we were able to improve performance by more than an order of magnitude on the benchmark algorithms, eliminating the processor bottleneck of CPU-bound tasks. Experiments with a prototype solid state nonvolative memory available today show 10X better throughput on random reads than disk, with a 2X speedup on a graph processing benchmark when compared to the use of local SATA disk.
Shielding Benchmark Computational Analysis
Hunter, H.T.; Slater, C.O.; Holland, L.B.; Tracz, G.; Marshall, W.J.; Parsons, J.L.
Over the past several decades, nuclear science has relied on experimental research to verify and validate information about shielding nuclear radiation for a variety of applications. These benchmarks are compared with results from computer code models and are useful for the development of more accurate cross-section libraries, computer code development of radiation transport modeling, and building accurate tests for miniature shielding mockups of new nuclear facilities. When documenting measurements, one must describe many parts of the experimental results to allow a complete computational analysis. Both old and new benchmark experiments, by any definition, must provide a sound basis for modeling more complex geometries required for quality assurance and cost savings in nuclear project development. Benchmarks may involve one or many materials and thicknesses, types of sources, and measurement techniques. In this paper the benchmark experiments of varying complexity are chosen to study the transport properties of some popular materials and thicknesses. These were analyzed using three-dimensional (3-D) models and continuous energy libraries of MCNP4B2, a Monte Carlo code developed at Los Alamos National Laboratory, New Mexico. A shielding benchmark library provided the experimental data and allowed a wide range of choices for source, geometry, and measurement data. The experimental data had often been used in previous analyses by reputable groups such as the Cross Section Evaluation Working Group (CSEWG) and the Organization for Economic Cooperation and Development/Nuclear Energy Agency Nuclear Science Committee (OECD/NEANSC).
Acoustical wave propagation in buried water filled pipes
Kondis, Antonios, 1980-
This thesis presents a comprehensive way of dealing with the problem of acoustical wave propagation in cylindrically layered media with a specific application in water-filled underground pipes. The problem is studied in ...
Randomized benchmarking with confidence
NASA Astrophysics Data System (ADS)
Wallman, Joel J.; Flammia, Steven T.
Randomized benchmarking is a promising tool for characterizing the noise in experimental implementations of quantum systems. In this paper, we prove that the estimates produced by randomized benchmarking (both standard and interleaved) for arbitrary Markovian noise sources are remarkably precise by showing that the variance due to sampling random gate sequences is small. We discuss how to choose experimental parameters, in particular the number and lengths of random sequences, in order to characterize average gate errors with rigorous confidence bounds. We also show that randomized benchmarking can be used to reliably characterize time-dependent Markovian noise (e.g., when noise is due to a magnetic field with fluctuating strength). Moreover, we identify a necessary property for time-dependent noise that is violated by some sources of non-Markovian noise, which provides a test for non-Markovianity.
Benchmarking in national health service procurement in Scotland.
Walker, Scott; Masson, Ron; Telford, Ronnie; White, David
The paper reports the results of a study on benchmarking activities undertaken by the procurement organization within the National Health Service (NHS) in Scotland, namely National Procurement (previously Scottish Healthcare Supplies Contracts Branch). NHS performance is of course politically important, and benchmarking is increasingly seen as a means to improve performance, so the study was carried out to determine if the current benchmarking approaches could be enhanced. A review of the benchmarking activities used by the private sector, local government and NHS organizations was carried out to establish a framework of the motivations, benefits, problems and costs associated with benchmarking. This framework was used to carry out the research through case studies and a questionnaire survey of NHS procurement organizations both in Scotland and other parts of the UK. Nine of the 16 Scottish Health Boards surveyed reported carrying out benchmarking during the last three years. The findings of the research were that there were similarities in approaches between local government and NHS Scotland Health, but differences between NHS Scotland and other UK NHS procurement organizations. Benefits were seen as significant and it was recommended that National Procurement should pursue the formation of a benchmarking group with members drawn from NHS Scotland and external benchmarking bodies to establish measures to be used in benchmarking across the whole of NHS Scotland. PMID:17958971
Benchmarking and Data Analysis�
Williams, K.
Benchmarking and Data Analysis Kellie Williams | Houston ISD ESL-KT-14-11-14 CATEE 2014: Clean Air Through Efficiency Conference, Dallas, Texas Nov. 18-20 Benchmarking ? Process of comparing data sets ? Baselines, Goals, KPIs ? Energy Star... ? Sample your data ? Standardize input ? Enhance content ESL-KT-14-11-14 CATEE 2014: Clean Air Through Efficiency Conference, Dallas, Texas Nov. 18-20 Data Analysis ? Key Performance Indicators ? Predictors ? Allow for re-evaluation ESL-KT-14-11-14 CATEE...
The poor sanitary conditions and water pollution problems EPA observed in the Kentucky counties of Harlan, Martin, Bath, and Montgomery were of the highest concern. The widespread scale of both the straight pipe issues as well as package plant wastewater problems present an envir...
A Comparison of the Results of the Numerical Analysis and the Physical Behavior of a Pipe Buried in Reactive Clay
Chaminda P. K. Gallage; J. K. Kodikara; Derek Chan; Paul Davis
Buried water and gas pipe systems form part of critical infrastructure providing essential services to the community. In many global population centres including in Australia, this vital infrastructure has been installed several decades ago, and dealing with frequent pipe failures become a major problem. There are clear evidences that pipe failures significantly depend on pipe strains induced by seasonal temperature
Hydrogen Piping Experience in Chevron
, 2" hydrogen piping failure) 4 #12;5 Hydrogen piping experience largely from hydroprocessing plantsHydrogen Piping Experience in Chevron Refining Ned Niccolls Materials Engineer Chevron Energy perspectives from long term use of hydrogen piping in refining. Piping specifications and practices. The (few
NASA Technical Reports Server (NTRS)
Edelstein, F.
A 1.2- by 1.8-m variable conductance heat pipe radiator was designed, built, and tested. The radiator has deployment capability and can passively control Freon-21 fluid loop temperatures under varying loads and environments. It consists of six grooved variable conductance heat pipes attached to a 0.032-in. aluminum panel. Heat is supplied to the radiator via a fluid header or a single-fluid flexible heat pipe header. The heat pipe header is an artery design that has a flexible section capable of bending up to 90 degrees. Radiator loads as high as 850 watts were successfully tested. Over a load variation of 200 watts, the outlet temperature of the Freon-21 fluid varied by 7 F. An alternate control system was also investigated which used a variable conductance heat pipe header attached to the heat pipe radiator panel.
Accelerated Randomized Benchmarking
Christopher Granade; Christopher Ferrie; D. G. Cory
Quantum information processing offers promising advances for a wide range of fields and applications, provided that we can efficiently assess the performance of the control applied in candidate systems. That is, we must be able to determine whether we have implemented a desired gate, and refine accordingly. Randomized benchmarking reduces the difficulty of this task by exploiting symmetries in quantum operations. Here, we bound the resources required for benchmarking and show that, with prior information, we can achieve several orders of magnitude better accuracy than in traditional approaches to benchmarking. Moreover, by building on state-of-the-art classical algorithms, we reach these accuracies with near-optimal resources. Our approach requires an order of magnitude less data to achieve the same accuracies and to provide online estimates of the errors in the reported fidelities. We also show that our approach is useful for physical devices by comparing to simulations. Our results thus enable the application of randomized benchmarking in new regimes, and dramatically reduce the experimental effort required to assess control fidelities in quantum systems. Finally, our work is based on open-source scientific libraries, and can readily be applied in systems of interest.
Benchmarking for maximum value.
Baldwin, Ed
Speaking at the most recent Healthcare Estates conference, Ed Baldwin, of international built asset consultancy EC Harris LLP, examined the role of benchmarking and market-testing--two of the key methods used to evaluate the quality and cost-effectiveness of hard and soft FM services provided under PFI healthcare schemes to ensure they are offering maximum value for money. PMID:19344004
ERIC Educational Resources Information Center
Creech, Joseph D.
This report details efforts that states in the Southern Regional Education Board (SREB) region have made to reach educational benchmarks for the year 2000. It focuses on readiness-for-school initiatives, such as preschool programs, and how schools in the SREB are advancing in this area. The report looks at student achievement, assessment of�
The ultimate steganalysis benchmark?
Andrew D. Ker
We present a new benchmark for binary steganalysis meth- ods, based on the asymptotic information (in the entropic sense) it gives about the presence of hidden data. The the- oretical foundation is quite unlike ad hoc performance mea- sures found in steganalysis literature that are based on false positive and negative rates. It is argued that this new met- ric
ERIC Educational Resources Information Center
Western Interstate Commission for Higher Education, 2013
Benchmarks: WICHE Region 2012 presents information on the West's progress in improving access to, success in, and financing of higher education. The information is updated annually to monitor change over time and encourage its use as a tool for informed discussion in policy and education communities. To establish a general context for the�
Airport Capacity Benchmark Report 2001
NSDL National Science Digital Library
Released in April 2001 by the FAA (Federal Aviation Administration), this report provides the first capacity benchmarks for 31 of the nation's busiest airports. Capacity benchmarks are defined as "the maximum number of flights an airport can routinely handle in an hour." The report finds, among other things, that at a number of airports so many flights are scheduled that it is simply not possible for all of them to take off and land on time. The worst offender in 2000 was New York LaGuardia, with 15.6 percent of takeoffs or landings delayed, more than twice as many as the second-ranked airport, Chicago O'Hare. Predictably, opinion is divided on the root of the problem, with the airlines blaming an antiquated air traffic control system and too few runways and critics blaming the airlines for over-scheduling at peak travel times. The full text of the 195-page report may be downloaded in .pdf or Word format at the FAA site.
Ernst, D.M.
A specially constructed heat pipe is described for use in fluidized bed combustors. Two distinct coatings are spray coated onto a heat pipe casing constructed of low thermal expansion metal, each coating serving a different purpose. The first coating forms aluminum oxide to prevent hydrogen permeation into the heat pipe casing, and the second coating contains stabilized zirconium oxide to provide abrasion resistance while not substantially affecting the heat transfer characteristics of the system.
Ernst, Donald M. (Leola, PA)
A specially constructed heat pipe for use in fluidized bed combustors. Two distinct coatings are spray coated onto a heat pipe casing constructed of low thermal expansion metal, each coating serving a different purpose. The first coating forms aluminum oxide to prevent hydrogen permeation into the heat pipe casing, and the second coating contains stabilized zirconium oxide to provide abrasion resistance while not substantially affecting the heat transfer characteristics of the system.
Hovis, Gregory L. (North Augusta, SC); Erickson, Scott A. (Augusta, GA); Blackmon, Bruce L. (Aiken, SC)
A pipe crawler apparatus particularly useful for 3-inch and 4-inch diameter pipes is provided. The pipe crawler apparatus uses a gripping apparatus in which a free end of a piston rod is modified with a bearing retaining groove. Bearings, placed within the groove, are directed against a camming surface of three respective pivoting support members. The non-pivoting ends of the support members carry a foot-like gripping member that, upon pivoting of the support member, engages the interior wall of the pipe.
Internal pipe attachment mechanism
Bast, R.M.; Chesnut, D.A.; Henning, C.D.; Lennon, J.P.; Pastrnak, J.W.; Smith, J.A.
An attachment mechanism is described for repairing or extending fluid carrying pipes, casings, conduits, etc. utilizing one-way motion of spring tempered fingers to provide a mechanical connection between the attachment mechanism and the pipe. The spring tempered fingers flex to permit insertion into a pipe to a desired insertion depth. The mechanical connection is accomplished by reversing the insertion motion and the mechanical leverage in the fingers forces them outwardly against the inner wall of the pipe. A seal is generated by crushing a sealing assembly by the action of setting the mechanical connection. 6 figures.
NASA Technical Reports Server (NTRS)
Gernert, Nelson J. (Inventor); Ernst, Donald M. (Inventor); Shaubach, Robert M. (Inventor)
An improved heat pipe with an external artery. The longitudinal slot in the heat pipe wall which interconnects the heat pipe vapor space with the external artery is completely filled with sintered wick material and the wall of the external artery is also covered with sintered wick material. This added wick structure assures that the external artery will continue to feed liquid to the heat pipe evaporator even if a vapor bubble forms within and would otherwise block the liquid transport function of the external artery.
Jamaican red clay tobacco pipes�
Heidtke, Kenan Paul
-made earthenware tobacco pipes has only been undertaken in the last few years. These red clay pipes occur at several colonial sites in North America, the Caribbean, and South America. This thesis will be a detailed study of the red clay pipes found in Jamaica... used on the pipes, and to offer possible explanations for the markings and stylistic attributes of the pipes. Locally made earthenware pipes from other colonial sites in the New World will also be examined to identify possible parallels...
Landmark-based autonomous navigation in sewerage pipes
Joachim Hertzberg; Frank Kirchner
We describe a method for an autonomous mobile robot to navigate through a system of sewerage pipes. Landmarks signalling positions in the pipe system have to be detected and classified, where classification is allowed do be unreliable. Self localization is interpreted as a partially observable Markov decision problem and solved accordingly. The method is implemented and used on a prototype
Application of remote-control in-pipe inspection technology
Watanabe, H.; Ozawa, K.
At nuclear power plants, there is a strong desire to maintain plant components soundly and to enhance the operation rate. Such a desire has increased the importance of the internal inspection of piping that accounts for a large percentage of plant components. To meet these needs, JGC Corporation in Japan has developed and practically applied various types of in-pipe traveling inspection robots applicable to piping that ranges in size from 4 to 24 in. in diameter. This paper introduces two robots that were developed recently: robot for 4- to 6-in. piping and a robot for 8- to 24-in. piping. Conventional in-pipe traveling inspection robots for small-diameter piping (6 in. and smaller) had difficulty passing inside 90-deg short elbows. The adoption of a spiral drive and special gears, however, has enabled passing inside of such elbows. Of conventional inspection robots for large-diameter piping, most of those which used a crawler drive to increase traction were apt to lose a certain amount of tractive force when they passed inside 90-deg short elbows. In the robot introduced herein, however, this problem was solved by developing a special crawler, which allowed slippage in the circumferential direction of the piping. At present, robots for small-diameter piping have been permanently installed and practically applied to the inspection of concentrator lines of radwaste facilities.
Merrigan, M.A.
Critical high temperature, high power applications in space nuclear power designs are near the current state of the art of heat pipe technology in terms of power density, operating temperature, and lifetime. Recent heat pipe development work at Los Alamos National Laboratory has involved performance testing of typical space reactor heat pipe designs to power levels in excess of 19 kW/cm/sup 2/ axially and 300 W/cm/sup 2/ radially at temperatures in the 1400 to 1500 K range. Operation at conditions in the 10 kW/cm/sup 2/ range has been sustained for periods of up to 1000 hours without evidence of performance degradation. The effective length for heat transport in these heat pipes was from 1.0 to 1.5 M. Materials used were molybdenum alloys with lithium employed as the heat pipe operating fluid. Shorter, somewhat lower power, molybdenum heat pipes have been life tested at Los Alamos for periods of greater than 25,000 hours at 1700 K with lithium and 20,000 hours at 1500/sup 0/K with sodium. These life test demonstrations and the attendant performance limit investigations provide an experimental basis for heat pipe application in space reactor design and represent the current state-of-the-art of high temperature heat pipe technology.
Yu. F. Maydanik
Loop heat pipes (LHPs) are two-phase heat-transfer devices with capillary pumping of a working fluid. They possess all the main advantages of conventional heat pipes, but owing to the original design and special properties of the capillary structure are capable of transferring heat efficiency for distances up to several meters at any orientation in the gravity field, or to several
Common causes of material degradation in buried piping
Jenkins, C.F.
Buried pipe may fail for innumerable reasons. Causes can be mechanical damage/breakage, chemically initiated corrosion, or a combination. Failures may originate either internally or externally on the pipe. They may be related to flaws in the design, to excessive or unanticipated internal pressure or ground level loading, and/or to poor or uncertain installation practice. Or the pipe may simply ``wear out`` in service. Steel is strong and very forgiving in underground applications, especially with regard to backfill. However, soil support developed through densification or compaction is critical for brittle concrete and vitrified clay tile pipe, and is very important for cast iron and plastic pipe. Chemistry of the soil determines whether or not it will enhance corrosion or other types of degradation. Various causes and mechanisms for deterioration of buried pipe are indicated. Some peculiarities of the different materials of construction are characterized. Repair methods and means to circumvent special problems are described.
Analysis of Rotary Bayonets and Piping
Chess, K.; Wendlandt, J.; /Fermilab
This report quantifies certain characteristics of the rotary bayonets and associated platform piping on the DO detector. The Vacuum Jacketed 4-inch x 6-inch and 1.5-inch x 3-inch and the 4-inch and 6-inch vacuum pipe articulating jumpers are considered here. The values of greatest importance are the forces required at the bayonet moment arms given in Table II and the stresses summarized in Table III. The forces required should be noted and checked that they are acceptable to the problem. The maximum bending stresses of the vacuum pipes do not exceed 1000 psi and are essentially negligible. The 4-inch x 6-inch vacuum jacketed line experiences the maximum bending stress of 10,300 psi. According to code B31.1, the maximum allowable bending stress is 25,500 psi. The major sources of error in these calculations should be summarized. First, all weights used were approximations and all lengths used were scaled from drawings. Second, while the FRAME MAC{trademark} models resemble the vacuum pipe articulating jumpers, they are definitely simplified. For instance, they do not account for the different stiffnesses of the unions. Finally, the bayonets in the ANSYS models consist of an outer jacket and an inner pipe fixed together at the end of the male sleeve. The actual bayonets are more complex and are composed of various sizes of tubes and pipes which affect the stiffness of the section.
Health care benchmarking 2003.
Hoppszallern, Suzanna
The latest benchmarking data reveal both old trends and some surprises. Once again, hospitals in high managed care markets outperformed those in low managed care markets in profitability measures, such as total margin and return on equity. However, hospitals in areas with low managed care penetration had a lower percentage of bad-debt expense and significantly fewer days in accounts receivable and more days cash on hand. PMID:12633068
Development of magnetic flux leakage pipe inspection robot using Hall sensors
Jin Tao; Que Peiwen; Tao Zhengsu
Pipeline safety evaluation is an important problem of industry, and this paper presents an automated pipe inspection robot to inspect pipeline defects. Based on magnetic flux leakage (MFL) method, the robot utilizes established mechatronic principles to produce a low-cost device capable of detecting inner pipe defects. The pipe inspection robot's design mainly includes its mechanical design, electronic design and data
An optical method for measuring the thickness of a falling condensate in gravity assisted heat pipe
NASA Astrophysics Data System (ADS)
Kasanick�, Martin; Lenhard, Richard; Kaduchov�, Katar�na; Malcho, Milan
A large number of variables is the main problem of designing systems which uses heat pipes, whether it is a traditional - gravity, or advanced - capillary, pulsating, advanced heat pipes. This article is a methodology for measuring the thickness of the falling condensate in gravitational heat pipes, with using the optical triangulation method, and the evaluation of risks associated with this method.
Automated Ultrasonic Pipe Weld Inspection
Wolfram A. Karl; Peter SCHULTE; Michael JOSWIG; Rainer KATTWINKEL
Summary This article contains an overview on automated ultrasonic w eld inspection for various pipe types. Some inspection steps might by carried out with portable t est equipment (e.g. pipe end test), but the weld inspection in all internationally relevant specif ications must be automated. The pipe geometry, the production process, and the further pipe usage determine if ND T
Flexible ultrasonic pipe inspection apparatus
Jenkins, C.F.; Howard, B.D.
Pipe crawlers, pipe inspection {open_quotes}rabbits{close_quotes} and similar vehicles are widely used for inspecting the interior surfaces of piping systems, storage tanks and process vessels for damaged or flawed structural features. This paper describes the design of a flexible, modular ultrasonic pipe inspection apparatus.
Computational evaluation of two reactor benchmark problems�
Cowan, James Anthony
U238 F238 F239 F240 F241 F242 A 41 OX16 HYDR B 10 B 11 VECTOR 4 8 23 BEGINC * 8. 7 8 Pu pin FUEL CELL (NEA WPPR Bnch Phase 2) CELL 6 SEQUENCE 2 NGROUP 23 3 3 NMESH 25 25 NREGION 4 0 4 NMATERIAL 4 1 PREOUT INITIATE ANNULUS 1 0. 4095 1... 242 1241 16 2001 10 11 *ISONAMES *U235 U238 F238 F239 F240 F241 F242 A241 OX16 HYDR B 10 B 11 VECTOR 4 8 23 BEGINC * U pan FUEL CELL (NEA WPPR Bnch Phase 2) CELL 6 SEQUENCE 2 NGROUP 23 3 3 NMESH 25 25 NREGION 4 0 4 NMATERIAL 4 1 PREOUT...
NASA Technical Reports Server (NTRS)
Wilcox, Brian (Inventor)
A gas pipe explorer formed of a plurality of connecting elements, and an articulation element between the connected elements. The connected elements include drive capabilities, and the articulation element allows the connected elements to traverse gas pipes of arbitrary shapes and sizes. A sensor may sends the characteristics of the gas pipe, and the communication element may send back those sends characteristics. The communication can be wired, over a tether connecting the device to a remote end. Alternatively, the connection can be wireless, driven by either a generator or a battery.
Improved Thin, Flexible Heat Pipes
NASA Technical Reports Server (NTRS)
Rosenfeld, John H.; Gernert, Nelson J.; Sarraf, David B.; Wollen, Peter J.; Surina, Frank C.; Fale, John E.
Flexible heat pipes of an improved type are fabricated as layers of different materials laminated together into vacuum- tight sheets or tapes. In comparison with prior flexible heat pipes, these flexible heat pipes are less susceptible to leakage. Other advantages of these flexible heat pipes, relative to prior flexible heat pipes, include high reliability and greater ease and lower cost of fabrication. Because these heat pipes are very thin, they are highly flexible. When coated on outside surfaces with adhesives, these flexible heat pipes can be applied, like common adhesive tapes, to the surfaces of heat sinks and objects to be cooled, even if those surfaces are curved.
Large variable conductance heat pipe. Transverse header
NASA Technical Reports Server (NTRS)
Edelstein, F.
The characteristics of gas-loaded, variable conductance heat pipes (VCHP) are discussed. The difficulties involved in developing a large VCHP header are analyzed. The construction of the large capacity VCHP is described. A research project to eliminate some of the problems involved in large capacity VCHP operation is explained.
How many ways can a pipe leak?
Vakhtang Putkaradze
When an underwater oil pipe develops a long crack along its surface, the oil rushes out setting the outer water in motion. How many ways can the flow of two fluids be established? I derive analytic solutions of Navier-Stokes equations describing this problem. I show that there are many (most probably infinite number) of flows for each set of parameter
Stewart Burn; Dhammika DeSilva; Matthias Eiswirth; Osama Hunaidi; Andrew Speers; Julian Thornton
Pipe leakage in Australia is perceived to be a major problem by many water authorities, both from an environmental point of view, as well as the associated costs that are incurred due to overdesign of our sewerage systems (to cope with wet weather loads) and the treatment of additional potable water that is lost due to leakage. This paper discusses
The design of a scalable, fixed-time computer benchmark
Gustafson, J.; Rover, D.; Elbert, S.; Carter, M.
By using the principle of fixed time benchmarking, it is possible to compare a very wide range of computers, from a small personal computer to the most powerful parallel supercomputer, an a single scale. Fixed-time benchmarks promise far greater longevity than those based on a particular problem size, and are more appropriate for grand challenge'' capability comparison. We present the design of a benchmark, SLALOM{trademark}, that scales automatically to the computing power available, and corrects several deficiencies in various existing benchmarks: it is highly scalable, it solves a real problem, it includes input and output times, and it can be run on parallel machines of all kinds, using any convenient language. The benchmark provides a reasonable estimate of the size of problem solvable on scientific computers. Results are presented that span six orders of magnitude for contemporary computers of various architectures. The benchmarks also can be used to demonstrate a new source of superlinear speedup in parallel computers. 15 refs., 14 figs., 3 tabs.
Cloyce D. Spradling
The benchmarks that make up the SPEC CPU2006 benchmark suite are set-up, run, timed, and scored by the CPU tools harness. The tools have evolved over time from a collection of edit-it-yourself makefiles, scripts, and an Excel spreadsheet to the current Perl-based suite. The basic purpose of the tools is to make life easier for the benchmarker; they make it
Image processing benchmark study
NASA Astrophysics Data System (ADS)
Miller, John W. V.; Eddy, C.; Waltz, Frederick M.; Hack, Ralf; Wood, James; Stokes, D.
This paper describes the benchmarking of image processing algorithms using high-performance workstations and personal desktop computers. For the various platforms evaluated which included machines from Sun, SGI, Apple, and Gateway, compiler options were varied to obtain the fastest execution times. Algorithms evaluated included typical image processing operations such as derivatives, logical operations, morphology, subtraction, median filter, and the new SKIPSM approach. Data were collected using the different platforms and are presented here in tabular form. The results indicate that the latest generation of personal computers have processing capabilities that are similar to UNIX-based work stations.
International Benchmarking for Monopoly Price Regulation: The Case of Australian Gas Distribution
Roger Carrington; Tim Coelli; Eric Groom
Price-cap regulation is widely applied to network industries. However, regulators often encounter the problem of asymmetric information on efficient costs. Benchmarking can help reduce this problem. We present a benchmarking analysis, conducted for an Australian regulator, that derives measures of efficiency for Australian gas distributors relative to U.S. counterparts. Several techniques, such as data envelopment analysis and stochastic frontier analysis,
Robot design for leak detection in water-pipe systems
Choi, Changrak
Leaks are major problem that occur in the water pipelines all around the world. Several reports indicate loss of around 20 to 30 percent of water in the distribution of water through water pipe systems. Such loss of water ...
Electrohydrodynamic heat pipe experiments
NASA Technical Reports Server (NTRS)
Jones, T. B.; Perry, M. P.
Experiments with two electrohydrodynamic heat pipes are reported. Both devices employ an electromechanical flow structure for axial liquid flow and a capillary wicking structure for (1) collection of condensed liquid at the cooled end and (2) distribution of this liquid at the heated end. One device has circumferential grooving for the capillary structure and the other has feltmetal wicking. The experiments successfully demonstrate the electrohydrodynamic heat pipe concept. Compatibility of the two circumferential wick structures with an axial electromechanical flow structure is also demonstrated. A significant mismatch of the capillary groove and electrohydrodynamic pumping capabilities results in severe hydrodynamic burn-out limiting in the first heat pipe. Both devices have very poor over-all thermal conductances of the order of 1-2 W/deg C, reflecting the generally poor heat-transfer properties of the dielectric working fluids required in electrohydrodynamic heat pipes.
Miniature pipe crawler tractor
McKay, M.D.; Anderson, M.O.; Ferrante, T.A.; Willis, W.D.
A pipe crawler tractor may comprise a half tractor assembly having a first base drive wheel, a second base drive wheel, and a top drive wheel. The drive wheels are mounted in spaced-apart relation so that the top drive wheel is positioned between the first and second base drive wheels. The mounting arrangement is also such that the first and second base drive wheels contact the inside surface of the pipe at respective first and second positions and so that the top drive wheel contacts the inside surface of the pipe at a third position, the third position being substantially diametrically opposed to the first and second positions. A control system connected to the half tractor assembly controls the rotation of the first base wheel, the second base wheel, and the top drive wheel to move the half tractor assembly within the pipe.
NASA Technical Reports Server (NTRS)
The heat pipe was developed to alternately cool and heat without using energy or any moving parts. It enables non-rotating spacecraft to maintain a constant temperature when the surface exposed to the Sun is excessively hot and the non Sun-facing side is very cold. Several organizations, such as Tropic-Kool Engineering Corporation, joined NASA in a subsequent program to refine and commercialize the technology. Heat pipes have been installed in fast food restaurants in areas where humid conditions cause materials to deteriorate quickly. Moisture removal was increased by 30 percent in a Clearwater, FL Burger King after heat pipes were installed. Relative humidity and power consumption were also reduced significantly. Similar results were recorded by Taco Bell, which now specifies heat pipe systems in new restaurants in the Southeast.
Ernst, Donald M. (Leola, PA); Sanzi, James L. (Lancaster, PA)
A heat pipe whose fluid can be repeatedly frozen and thawed without damage to the casing. An additional part is added to a conventional heat pipe. This addition is a simple porous structure, such as a cylinder, self-supporting and free standing, which is dimensioned with its diameter not spanning the inside transverse dimension of the casing, and with its length surpassing the depth of maximum liquid.
Self-benchmarking Guide for Cleanrooms: Metrics, Benchmarks, Actions
Mathew, Paul; Sartor, Dale; Tschudi, William
This guide describes energy efficiency metrics and benchmarks that can be used to track the performance of and identify potential opportunities to reduce energy use in laboratory buildings. This guide is primarily intended for personnel who have responsibility for managing energy use in existing laboratory facilities - including facilities managers, energy managers, and their engineering consultants. Additionally, laboratory planners and designers may also use the metrics and benchmarks described in this guide for goal-setting in new construction or major renovation. This guide provides the following information: (1) A step-by-step outline of the benchmarking process. (2) A set of performance metrics for the whole building as well as individual systems. For each metric, the guide provides a definition, performance benchmarks, and potential actions that can be inferred from evaluating this metric. (3) A list and descriptions of the data required for computing the metrics. This guide is complemented by spreadsheet templates for data collection and for computing the benchmarking metrics. This guide builds on prior research supported by the national Laboratories for the 21st Century (Labs21) program, supported by the U.S. Department of Energy and the U.S. Environmental Protection Agency. Much of the benchmarking data are drawn from the Labs21 benchmarking database and technical guides. Additional benchmark data were obtained from engineering experts including laboratory designers and energy managers.
Self-benchmarking Guide for Laboratory Buildings: Metrics, Benchmarks, Actions
Mathew, Paul; Greenberg, Steve; Sartor, Dale
This guide describes energy efficiency metrics and benchmarks that can be used to track the performance of and identify potential opportunities to reduce energy use in laboratory buildings. This guide is primarily intended for personnel who have responsibility for managing energy use in existing laboratory facilities - including facilities managers, energy managers, and their engineering consultants. Additionally, laboratory planners and designers may also use the metrics and benchmarks described in this guide for goal-setting in new construction or major renovation. This guide provides the following information: (1) A step-by-step outline of the benchmarking process. (2) A set of performance metrics for the whole building as well as individual systems. For each metric, the guide provides a definition, performance benchmarks, and potential actions that can be inferred from evaluating this metric. (3) A list and descriptions of the data required for computing the metrics. This guide is complemented by spreadsheet templates for data collection and for computing the benchmarking metrics. This guide builds on prior research supported by the national Laboratories for the 21st Century (Labs21) program, supported by the U.S. Department of Energy and the U.S. Environmental Protection Agency. Much of the benchmarking data are drawn from the Labs21 benchmarking database and technical guides. Additional benchmark data were obtained from engineering experts including laboratory designers and energy managers.
Benchmarking concentrating photovoltaic systems
NASA Astrophysics Data System (ADS)
Duerr, Fabian; Muthirayan, Buvaneshwari; Meuret, Youri; Thienpont, Hugo
Integral to photovoltaics is the need to provide improved economic viability. To achieve this goal, photovoltaic technology has to be able to harness more light at less cost. A large variety of concentrating photovoltaic concepts has provided cause for pursuit. To obtain a detailed profitability analysis, a flexible evaluation is crucial for benchmarking the cost-performance of this variety of concentrating photovoltaic concepts. To save time and capital, a way to estimate the cost-performance of a complete solar energy system is to use computer aided modeling. In this work a benchmark tool is introduced based on a modular programming concept. The overall implementation is done in MATLAB whereas Advanced Systems Analysis Program (ASAP) is used for ray tracing calculations. This allows for a flexible and extendable structuring of all important modules, namely an advanced source modeling including time and local dependence, and an advanced optical system analysis of various optical designs to obtain an evaluation of the figure of merit. An important figure of merit: the energy yield for a given photovoltaic system at a geographical position over a specific period, can be calculated.
STEALTH: a Lagrange explicit finite difference code for solids, structural, and thermohydraulic analysis. Volume 6: piping systems manual. Computer code manual
Cohen, L.M.
This volume documents the STEALTH piping numerical code, which can simulate the time-dependent flow phenomena that occur in piping systems. This volume also contains the input instructions for the STEALTH piping code, and a sample problem of a pipe flow simulation.
NASA Technical Reports Server (NTRS)
The GTRAN program was developed to solve transient, as well as steady state, problems for gas piping systems. GTRAN capabilities allow for the analysis of a variety of system configurations and components. These include: multiple pipe junctions; valves that change position with time; fixed restrictions (orifices, manual valves, filters, etc.); relief valves; constant pressure sources; and heat transfer for insulated piping and piping subjected to free or forced convection. In addition, boundary conditions can be incorporated to simulate specific components. The governing equations of GTRAN are the one-dimensional transient gas dynamic equations. The three equations for pressure, velocity, and density are reduced to numerical equations using an implicit Crank-Nicholson finite difference technique. Input to GTRAN includes a description of the piping network, the initial conditions, and any events (e.g. valve closings) occuring during the period of analysis. Output includes pressure, velocity, and density versus time. GTRAN is written in FORTRAN 77 for batch execution and has been implemented on a DEC VAX series computer. GTRAN was developed in 1983.
Internal Benchmarking for Institutional Effectiveness
ERIC Educational Resources Information Center
Ronco, Sharron L.
Internal benchmarking is an established practice in business and industry for identifying best in-house practices and disseminating the knowledge about those practices to other groups in the organization. Internal benchmarking can be done with structures, processes, outcomes, or even individuals. In colleges or universities with multicampuses or a�
Benchmarking Home Health Care Data
Paula Howard
Benchmarking data is a relatively new process in the home health care industry. But the results can assist an agency in the strategic planning� staffing needs and program development�for the present and future. This descriptive research project benchmarked home health care data at the national, state (ie, North Carolina), and local (ie, Triangle area: Raleigh, Durham, and Chapel Hill) level
Former Yosemite Hydrologic Benchmark Streamgage
In this image, the former USGS Hydrologic Benchmark Streamgage on the Merced River in Yosemite Valley can be seen. Hydrologic Benchmark streamgages are those at which no human development exists upstream of the streamgage. The streamgage station has been in existence since 1915, and was replaced by ...
The NAS kernel benchmark program
NASA Technical Reports Server (NTRS)
Bailey, D. H.; Barton, J. T.
A collection of benchmark test kernels that measure supercomputer performance has been developed for the use of the NAS (Numerical Aerodynamic Simulation) program at the NASA Ames Research Center. This benchmark program is described in detail and the specific ground rules are given for running the program as a performance test.
NAS Grid Benchmarks: A Tool for Grid Space Exploration
NASA Technical Reports Server (NTRS)
Frumkin, Michael; VanderWijngaart, Rob F.; Biegel, Bryan (Technical Monitor)
We present an approach for benchmarking services provided by computational Grids. It is based on the NAS Parallel Benchmarks (NPB) and is called NAS Grid Benchmark (NGB) in this paper. We present NGB as a data flow graph encapsulating an instance of an NPB code in each graph node, which communicates with other nodes by sending/receiving initialization data. These nodes may be mapped to the same or different Grid machines. Like NPB, NGB will specify several different classes (problem sizes). NGB also specifies the generic Grid services sufficient for running the bench-mark. The implementor has the freedom to choose any specific Grid environment. However, we describe a reference implementation in Java, and present some scenarios for using NGB.
Aircraft Engine Gas Path Diagnostic Methods: Public Benchmarking Results
NASA Technical Reports Server (NTRS)
Simon, Donald L.; Borguet, Sebastien; Leonard, Olivier; Zhang, Xiaodong (Frank)
Recent technology reviews have identified the need for objective assessments of aircraft engine health management (EHM) technologies. To help address this issue, a gas path diagnostic benchmark problem has been created and made publicly available. This software tool, referred to as the Propulsion Diagnostic Method Evaluation Strategy (ProDiMES), has been constructed based on feedback provided by the aircraft EHM community. It provides a standard benchmark problem enabling users to develop, evaluate and compare diagnostic methods. This paper will present an overview of ProDiMES along with a description of four gas path diagnostic methods developed and applied to the problem. These methods, which include analytical and empirical diagnostic techniques, will be described and associated blind-test-case metric results will be presented and compared. Lessons learned along with recommendations for improving the public benchmarking processes will also be presented and discussed.
Status and Benchmarking of the Free Boundary Equilibrium Code FREEBIE
NASA Astrophysics Data System (ADS)
Urban, Jakub; Artaud, Jean-Francois; Basiuk, Vincent; Besseghir, Karim; Huynh, Philippe; Kim, Sunhee; Lister, Jonathan Bryan; Nardon, Eric
FREEBIE is a recent free boundary equilibrium (FBE) code, which solves the temporal evolution of tokamak equilibrium, described by the Grad-Shafranov equation and circuit equations for active and passive poloidal field components. FREEBIE can be run stand-alone, within the transport code CRONOS or on the ITM (European Integrated Tokamak Modelling) platform. FREEBIE with prescribed plasma profiles has already been successfully benchmarked against DINA simulations and TCV experiments. Here we report on the current status of the code coupling with transport solvers and benchmarking of fully consistent transport-FBE simulations. A benchmarking procedure is developed and applied to several ITER cases using FREEBIE, DINA and CEDRES++. The benchmarks indicate that because of the different methods and the complexity of the problem, results obtained from the different codes are comparable only to a certain extent. FREEBIE is a recent free boundary equilibrium (FBE) code, which solves the temporal evolution of tokamak equilibrium, described by the Grad-Shafranov equation and circuit equations for active and passive poloidal field components. FREEBIE can be run stand-alone, within the transport code CRONOS or on the ITM (European Integrated Tokamak Modelling) platform. FREEBIE with prescribed plasma profiles has already been successfully benchmarked against DINA simulations and TCV experiments. Here we report on the current status of the code coupling with transport solvers and benchmarking of fully consistent transport-FBE simulations. A benchmarking procedure is developed and applied to several ITER cases using FREEBIE, DINA and CEDRES++. The benchmarks indicate that because of the different methods and the complexity of the problem, results obtained from the different codes are comparable only to a certain extent. Supported by GACR 13-38121P, EURATOM, AS CR AV0Z 20430508, MSMT 7G10072 and MSMT LM2011021.
Benchmarking foreign electronics technologies
Bostian, C.W.; Hodges, D.A.; Leachman, R.C.; Sheridan, T.B.; Tsang, W.T.; White, R.M.
This report has been drafted in response to a request from the Japanese Technology Evaluation Center`s (JTEC) Panel on Benchmarking Select Technologies. Since April 1991, the Competitive Semiconductor Manufacturing (CSM) Program at the University of California at Berkeley has been engaged in a detailed study of quality, productivity, and competitiveness in semiconductor manufacturing worldwide. The program is a joint activity of the College of Engineering, the Haas School of Business, and the Berkeley Roundtable on the International Economy, under sponsorship of the Alfred P. Sloan Foundation, and with the cooperation of semiconductor producers from Asia, Europe and the United States. Professors David A. Hodges and Robert C. Leachman are the project`s Co-Directors. The present report for JTEC is primarily based on data and analysis drawn from that continuing program. The CSM program is being conducted by faculty, graduate students and research staff from UC Berkeley`s Schools of Engineering and Business, and Department of Economics. Many of the participating firms are represented on the program`s Industry Advisory Board. The Board played an important role in defining the research agenda. A pilot study was conducted in 1991 with the cooperation of three semiconductor plants. The research plan and survey documents were thereby refined. The main phase of the CSM benchmarking study began in mid-1992 and will continue at least through 1997. reports are presented on the manufacture of integrated circuits; data storage; wireless technology; human-machine interfaces; and optoelectronics. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.
Heat pipes and use of heat pipes in furnace exhaust
Polcyn, Adam D. (Pittsburgh, PA)
An array of a plurality of heat pipe are mounted in spaced relationship to one another with the hot end of the heat pipes in a heated environment, e.g. the exhaust flue of a furnace, and the cold end outside the furnace. Heat conversion equipment is connected to the cold end of the heat pipes.
Apparatus for moving a pipe inspection probe through piping
Zollinger, W.T.; Appel, D.K.; Lewis, G.W.
A method and apparatus are disclosed for controllably moving devices for cleaning or inspection through piping systems, including piping systems with numerous piping bends therein, by using hydrostatic pressure of a working fluid introduced into the piping system. The apparatus comprises a reservoir or other source for supplying the working fluid to the piping system, a launch tube for admitting the device into the launcher and a reversible, positive displacement pump for controlling the direction and flow rate of the working fluid. The device introduced into the piping system moves with the flow of the working fluid through the piping system. The launcher attaches to the valved ends of a piping system so that fluids in the piping system can recirculate in a closed loop. The method comprises attaching the launcher to the piping system, supplying the launcher with working fluid, admitting the device into the launcher, pumping the working fluid in the direction and at the rate desired so that the device moves through the piping system for pipe cleaning or inspection, removing the device from the launcher, and collecting the working fluid contained in the launcher. 8 figs.
Benchmarking of energy time series
Williamson, M.A.
Benchmarking consists of the adjustment of time series data from one source in order to achieve agreement with similar data from a second source. The data from the latter source are referred to as the benchmark(s), and often differ in that they are observed at a lower frequency, represent a higher level of temporal aggregation, and/or are considered to be of greater accuracy. This report provides an extensive survey of benchmarking procedures which have appeared in the statistical literature, and reviews specific benchmarking procedures currently used by the Energy Information Administration (EIA). The literature survey includes a technical summary of the major benchmarking methods and their statistical properties. Factors influencing the choice and application of particular techniques are described and the impact of benchmark accuracy is discussed. EIA applications and procedures are reviewed and evaluated for residential natural gas deliveries series and coal production series. It is found that the current method of adjusting the natural gas series is consistent with the behavior of the series and the methods used in obtaining the initial data. As a result, no change is recommended. For the coal production series, a staged approach based on a first differencing technique is recommended over the current procedure. A comparison of the adjustments produced by the two methods is made for the 1987 Indiana coal production series. 32 refs., 5 figs., 1 tab.
Benchmarking in academic pharmacy departments.
Bosso, John A; Chisholm-Burns, Marie; Nappi, Jean; Gubbins, Paul O; Ross, Leigh Ann
Benchmarking in academic pharmacy, and recommendations for the potential uses of benchmarking in academic pharmacy departments are discussed in this paper. Benchmarking is the process by which practices, procedures, and performance metrics are compared to an established standard or best practice. Many businesses and industries use benchmarking to compare processes and outcomes, and ultimately plan for improvement. Institutions of higher learning have embraced benchmarking practices to facilitate measuring the quality of their educational and research programs. Benchmarking is used internally as well to justify the allocation of institutional resources or to mediate among competing demands for additional program staff or space. Surveying all chairs of academic pharmacy departments to explore benchmarking issues such as department size and composition, as well as faculty teaching, scholarly, and service productivity, could provide valuable information. To date, attempts to gather this data have had limited success. We believe this information is potentially important, urge that efforts to gather it should be continued, and offer suggestions to achieve full participation. PMID:21179251
Benchmarking in Academic Pharmacy Departments
Chisholm-Burns, Marie; Nappi, Jean; Gubbins, Paul O.; Ross, Leigh Ann
Benchmarking in academic pharmacy, and recommendations for the potential uses of benchmarking in academic pharmacy departments are discussed in this paper. Benchmarking is the process by which practices, procedures, and performance metrics are compared to an established standard or best practice. Many businesses and industries use benchmarking to compare processes and outcomes, and ultimately plan for improvement. Institutions of higher learning have embraced benchmarking practices to facilitate measuring the quality of their educational and research programs. Benchmarking is used internally as well to justify the allocation of institutional resources or to mediate among competing demands for additional program staff or space. Surveying all chairs of academic pharmacy departments to explore benchmarking issues such as department size and composition, as well as faculty teaching, scholarly, and service productivity, could provide valuable information. To date, attempts to gather this data have had limited success. We believe this information is potentially important, urge that efforts to gather it should be continued, and offer suggestions to achieve full participation. PMID:21179251
Heiguero, V.M.
This new edition brings together in one source the formulas and technical data that previously had to be gathered from many scattered sources. The mathematical complexity of refinery, petrochemical, and power-plant piping design requires the use of many highly sophisticated computer programs, all of which require extensive input. The tables in this handbook not only provide these necessary input data but also help check the accuracy of the program output, eliminate interpolation, and reduce expensive ''engineering time''. New Material in this second edition covers piping branch reinforcements and stiffness coefficients for nozzles on cylindrical vessels. In addition, it includes the latest ANSI Piping Codes B31.1(1983) and B31.3(1984).
Leslie, James C. (Fountain Valley, CA); Leslie, II, James C. (Mission Viejo, CA); Heard, James (Huntington Beach, CA); Truong, Liem (Anaheim, CA), Josephson; Marvin (Huntington Beach, CA), Neubert; Hans (Anaheim, CA)
A composite pipe segment is formed to include tapered in wall thickness ends that are each defined by opposed frustoconical surfaces conformed for self centering receipt and intimate bonding contact within an annular space between corresponding surfaces of a coaxially nested set of metal end pieces. The distal peripheries of the nested end pieces are then welded to each other and the sandwiched and bonded portions are radially pinned. The composite segment may include imbedded conductive leads and the axial end portions of the end pieces are shaped to form a threaded joint with the next pipe assembly that includes a contact ring in one pipe assembly pierced by a pointed contact in the other to connect the corresponding leads across the joint.
Apparatus for inspecting piping
Zollingger, W.T.; Appel, D.K.; Park, L.R.
An inspection rabbit is described for inspecting piping systems having severe bends therein. The rabbit consists of a flexible, modular body containing a miniaturized eddy current inspection probe, a self-contained power supply for proper operation of the rabbit, an outer surface that allows ease of movement through piping systems and means for transmitting data generated by the inspection device. The body is preferably made of flexible polyvinyl chloride (PVC) tubing or, alternatively, silicone rubber with a shrink wrapping of polytetrafluoroethylene (TEFLON{trademark}). The body is formed to contain the power supply, preferably a plurality of batteries, and a spool of communication wire that connects to a data processing computer external to the piping system. 6 figures.
Apparatus for inspecting piping
Zollingger, W. Thor (Martinez, GA); Appel, D. Keith (Aiken, SC); Park, Larry R. (Raleigh, NC)
An inspection rabbit for inspecting piping systems having severe bends therein. The rabbit consists of a flexible, modular body containing a miniaturized eddy current inspection probe, a self-contained power supply for proper operation of the rabbit, an outer surface that allows ease of movement through piping systems and means for transmitting data generated by the inspection device. The body is preferably made of flexible polyvinyl chloride (PVC) tubing or, alternatively, silicone rubber with a shrink wrapping of polytetrafluoroethylene (TEFLON.RTM.). The body is formed to contain the power supply, preferably a plurality of batteries, and a spool of communication wire that connects to a data processing computer external to the piping system.
Moore, William B; Webb, A Alexander G
The heat transport and lithospheric dynamics of early Earth are currently explained by plate tectonic and vertical tectonic models, but these do not offer a global synthesis consistent with the geologic record. Here we use numerical simulations and comparison with the geologic record to explore a heat-pipe model in which volcanism dominates surface heat transport. These simulations indicate that a cold and thick lithosphere developed as a result of frequent volcanic eruptions that advected surface materials downwards. Declining heat sources over time led to an abrupt transition to plate tectonics. Consistent with model predictions, the geologic record shows rapid volcanic resurfacing, contractional deformation, a low geothermal gradient across the bulk of the lithosphere and a rapid decrease in heat-pipe volcanism after initiation of plate tectonics. The heat-pipe Earth model therefore offers a coherent geodynamic framework in which to explore the evolution of our planet before the onset of plate tectonics. PMID:24067709
Benchmarking numerical freeze/thaw models
NASA Astrophysics Data System (ADS)
R�haak, Wolfram; Anbergen, Hauke; Molson, John; Grenier, Christophe; Sass, Ingo
The modeling of freezing and thawing of water in porous media is of increasing interest, and for which very different application areas exist. For instance, the modeling of permafrost regression with respect to climate change issues is one area, while others include geotechnical applications in tunneling and for borehole heat exchangers which operate at temperatures below the freezing point. The modeling of these processes requires the solution of a coupled non-linear system of partial differential equations for flow and heat transport in space and time. Different code implementations have been developed in the past. Analytical solutions exist only for simple cases. Consequently, an interest has arisen in benchmarking different codes with analytical solutions, experiments and purely numerical results, similar to the long-standing DECOVALEX and the more recent "Geothermal Code Comparison" activities. The name for this freezing/ thawing benchmark consortium is INTERFROST. In addition to the well-known so-called Lunardini solution for a 1D case (case T1), two different 2D problems will be presented, one which represents melting of a frozen inclusion (case TH2) and another which represents the growth or thaw of permafrost around a talik (case TH3). These talik regions are important for controlling groundwater movement within a mainly frozen ground. First results of the different benchmark results will be shown and discussed.
BCSC Screening Performance Benchmarks: Benchmarks for Cancers (2009 Data)
Skip to Main Content Home � | � Data � | � Statistics � | � Tools � | � Collaborations � | � Work with Us � | � Publications � | � About � | � Links Benchmarks for Cancers for Screening Mammography Examinations from 2004 - 2008 -- based on BCSC data
BCSC Screening Performance Benchmarks: Benchmarks for (2007 Data)
Skip to Main Content Home � | � Data � | � Statistics � | � Tools � | � Collaborations � | � Work with Us � | � Publications � | � About � | � Links Benchmarks for Cancers for Screening Mammography Examinations from 1996 - 2005 --- based on BCSC data
Piping-System Solutions Using Mathcad
Kostic, Milivoje M.
Piping-System Solutions Using Mathcad B. K. HODGE,1 ROBERT P. TAYLOR2 1 Mechanical Engineering associated with piping systems. Examples include series piping systems, parallel piping systems, and pipingScience (www.interscience.wiley.com.); DOI 10.1002/cae.10010 Keywords: piping systems; Mathcad, Hardy
Heat pipe applications development in Europe
O. Brost; W. D. Muenzel
Heat pipes for the cryogenic temperature range are considered along with low temperature heat pipes, heat pipes in the mid-temperature range, and heat pipes in the high temperature range. A description of structures for high performance heat pipes is presented. The characteristics of isothermal spaces obtained by the use of simple heat pipes are examined, taking into account isothermal inserts,
NSDL National Science Digital Library
The Tippy Tap hand-washing station is an inexpensive and effective device used extensively in the developing world. One shortcoming of the homemade device is that it must be manually refilled with water and therefore is of limited use in high-traffic areas. In this activity, student teams design, prototype and test piping systems to transport water from a storage tank to an existing Tippy Tap hand-washing station, thereby creating a more efficient hand-washing station. Through this example service-learning engineering project, students learn basic fluid dynamic principles that are needed for creating efficient piping systems.
NASA Astrophysics Data System (ADS)
Burbach, T.
The heat transfer from hot water to a cold copper pipe in laminar and turbulent flow condition is determined. The mean flow through velocity in the pipe, relative test length and initial temperature in the vessel were varied extensively during tests. Measurements confirm Nusselt's theory for large test lengths in laminar range. A new equation is derived for heat transfer for large starting lengths which agrees satisfactorily with measurements for large starting lengths. Test results are compared with the new Prandtl equation for heat transfer and correlated well. Test material for 200- and to 400-diameter test length is represented at four different vessel temperatures.
NASA Technical Reports Server (NTRS)
Burbach, T.
The heat transfer from hot water to a cold copper pipe in laminar and turbulent flow condition is determined. The mean flow through velocity in the pipe, relative test length and initial temperature in the vessel were varied extensively during tests. Measurements confirm Nusselt's theory for large test lengths in laminar range. A new equation is derived for heat transfer for large starting lengths which agrees satisfactorily with measurements for large starting lengths. Test results are compared with the new Prandtl equation for heat transfer and correlated well. Test material for 200- and to 400-diameter test length is represented at four different vessel temperatures.
NASA Technical Reports Server (NTRS)
Marcus, B. D.; Fleischman, G. L. (inventors)
Flat plate (vapor chamber) heat pipes were made by enclosing metal wicking between two capillary grooved flat panels. These heat pipes provide a unique configuration and have good capacity and conductance capabilities in zero gravity. When these flat plate vapor chamber heat pipes are heated or cooled, the surfaces are essentially isothermal, varying only 3 to 5 C over the panel surface.
Kronberg, J.W.
This invention pertains to a pipe fitting for joining two pipes at a desired, preselected angle and comprises a curved section of pipe with a generally circular cross-section. One end of the curved pipe is preferably furnished with a bell fitting. The other end is adapted to be inserted into the bell of another pipe fitting. The surface of the pipe is marked with circumferential lines spaced at several-degree intervals, the lines corresponding to the angle of the bend which will result if the pipe is cut along that line. The outer diameter of the pipe is closely controlled to be the same throughout its length as the outer diameter of a straight pipe, so the cut end can be inserted into the bell of another fitting without further treatment, and the radius of curvature of the pipe is larger than a standard street elbow, preferably three to ten times the diameter of the pipe. Thus, a cut approximately perpendicular to the axial centerline can be made at any point along the length of the pipe to form an elbow of any desired angle.
Kronberg, J.W.
This invention pertains to a pipe fitting for joining two pipes at a desired, preselected angle and comprises a curved section of pipe with a generally circular cross-section. One end of the curved pipe is preferably furnished with a bell fitting. The other end is adapted to be inserted into the bell of another pipe fitting. The surface of the pipe is marked with circumferential lines spaced at several-degree intervals, the lines corresponding to the angle of the bend which will result if the pipe is cut along that line. The outer diameter of the pipe is closely controlled to be the same throughout its length as the outer diameter of a straight pipe, so the cut end can be inserted into the bell of another fitting without further treatment, and the radius of curvature of the pipe is larger than a standard street elbow, preferably three to ten times the diameter of the pipe. Thus, a cut approximately perpendicular to the axial centerline can be made at any point along the length of the pipe to form an elbow of any desired angle.
H. Kreeb; H. Koch
Heat pipes with a capillary structure consisting of axial grooves are discussed which are intended for use in various space vehicles. The heat pipes are produced from a modular system that has more than 15 pipe geometries for both standard and cryogenic temperatures and is based on the concept of an extruded aluminum profile with longitudinal grooves serving as capillaries.
Reusable high-temperature heat pipes and heat pipe panels
NASA Technical Reports Server (NTRS)
Camarda, Charles J. (inventor); Ransone, Philip O. (inventor)
A reusable, durable heat pipe which is capable of operating at temperatures up to about 3000 F in an oxidizing environment and at temperatures above 3000 F in an inert or vacuum environment is produced by embedding a refractory metal pipe within a carbon-carbon composite structure. A reusable, durable heat pipe panel is made from an array of refractory-metal pipes spaced from each other. The reusable, durable, heat-pipe is employed to fabricate a hypersonic vehicle leading edge and nose cap.
Defect characterization in pipe-to-pipe welds in large diameter stainless steel piping
Rawl, D.E. Jr.; West, S.L.; Wheeler, D.A.; Louthan, M.R. Jr.
Metallurgical evaluation of pipe-to-pipe welds in large-diameter, Type 304 stainless steel piping used to construct the moderator/coolant water systems for Savannah River Site reactors has demonstrated that small weld defects found in this 1950-vintage system do not compromise the integrity of the system. The weld defects were too small for detection by the pre-service standard radiographic inspection, but were found through systematic ultrasonic testing (UT) and penetrant testing (PT) evaluations of piping that had been removed during upgrades to the piping system. The defects include lack of weld penetration, slag inclusions, and other weld metal discontinuities. These discontinuities typically did not propagate during more than 35 years of service. The defects examined were too small and isolated to degrade the mechanical properties of the pipe-to-pipe weldments and therefore did not compromise the integrity of the piping system. 14 refs., 7 figs.
DataLaViSTA : A Packet-based Pipes and Filters Architecture for Data Handling in Virtual Environments
Kuhlen, Torsten
DataLaViSTA : A Packet-based Pipes and Filters Architecture for Data Handling in Virtual problems can be found in the pipes and filters architecture, where data is processed in a stream-like wayLaViSTA module. Keywords: Virtual Reality, pipes and filters, multithreading, software architecture 1
Virtual machine performance benchmarking.
Langer, Steve G; French, Todd
The attractions of virtual computing are many: reduced costs, reduced resources and simplified maintenance. Any one of these would be compelling for a medical imaging professional attempting to support a complex practice on limited resources in an era of ever tightened reimbursement. In particular, the ability to run multiple operating systems optimized for different tasks (computational image processing on Linux versus office tasks on Microsoft operating systems) on a single physical machine is compelling. However, there are also potential drawbacks. High performance requirements need to be carefully considered if they are to be executed in an environment where the running software has to execute through multiple layers of device drivers before reaching the real disk or network interface. Our lab has attempted to gain insight into the impact of virtualization on performance by benchmarking the following metrics on both physical and virtual platforms: local memory and disk bandwidth, network bandwidth, and integer and floating point performance. The virtual performance metrics are compared to baseline performance on "bare metal." The results are complex, and indeed somewhat surprising. PMID:21207096
Benchmarking unstructured systems
Brice, L.; Connell, J.; Lockhart, G.
Systems developed without the advantage of structured techniques can currently be found, even though most managers agree that the lack of such techniques is apt to produce an inferior product. When an unstructured system is identified, management must decide if it should be rewritten according to modern standards. The case study presented here describes how management in one Data Processing shop made that decision and learned something about their perceptions of the staff as well. To be judged successful, a system should be friendly, useful and easily maintainable. Research has shown that psychologically complex programs are more expensive to maintain than those developed with structured techniques, free from such complexity. In this study, three suspect systems were statistically measured against a base system. When a suspect system proved at least as psychologically complex as the base system, future maintenance costs were assumed to be at least as high as for the benchmark system. In addition to judging whether or not a system should be rewritten to provide ease of maintenance, the study provided management with a more accurate view of programmer work habits. Programmers previously judged to be extremely competent had created a high level of psychological complexity which is expected to result in high maintenance costs when other programmers become responsible for the system.
Outlook for Industrial Energy Benchmarking
Hartley, Z.
OUTLOOK FOR INDUSTRIAL ENERGY BENCHMARKING Zoe Hartley Environmental Protection Specialist U.S. Environmental Protection Agency Washington, DC ABSTRACT The U.S. Environmental Protection Agency is exploring options to sponsor an ~d~ ~~gy...
Beneficial impact of coatings on biological generation of sulfide in concrete sewer pipes
Esam H. Hewayde; George F. Nakhla; Erez N. Allouche; Prasanna K. Mohan
Hydrogen sulfide is a serious problem for many municipalities across North America and worldwide. Odor, safety, and corrosion are the major problems associated with the presence of hydrogen sulfide in sewerage systems. This paper investigates the effect on sulfide generation of using innovative coatings in concrete sewer pipes. A pilot-scale model, consisting of three concrete pipes (each 75�cm in length
Memory-intensive benchmarks: IRAM vs. cache-based machines
Gaeke, Brian G.; Husbands, Parry; Kim, Hyun Jin; Li, Xiaoye S.; Moon, Hyun Jin; Oliker, Leonid; Yelick, Katherine A.; Biswas, Rupak
The increasing gap between processor and memory performance has led to new architectural models for memory-intensive applications. In this paper, we explore the performance of a set of memory-intensive benchmarks and use them to compare the performance of conventional cache-based microprocessors to a mixed logic and DRAM processor called VIRAM. The benchmarks are based on problem statements, rather than specific implementations, and in each case we explore the fundamental hardware requirements of the problem, as well as alternative algorithms and data structures that can help expose fine-grained parallelism or simplify memory access patterns. The benchmarks are characterized by their memory access patterns, their basic structures, and the ratio of computation to memory operation.
Benchmarking SAT Solvers for Bounded Model Checking
Emmanuel Zarpas
Modern SAT solvers are highly dependent on heuristics. Therefore, benchmarking is of prime importance in evaluating the per- formances of different solvers. However, relevant benchmarking is not necessarily straightforward. We present our experiments using the IBM CNF Benchmark on several SAT solvers. Using the results, we attempt to define guidelines for a relevant benchmarking methodology, using SAT solvers for real
This new edition brings together in one source the formulas and technical data that previously had to be gathered from many scattered sources. The mathematical complexity of refinery, petrochemical, and power-plant piping design requires the use of many highly sophisticated computer programs, all of which require extensive input. The tables in this handbook not only provide these necessary input data
Medved, P.; Thomas, H. [Acme Steel Co., Chicago, IL (United States)
Acme Steel had operated the larry car with an attached jumper pipe since 1977. Acme had been able to meet the State Implementation Plan. With the advent of the Clean Air Act, Acme did not feel it could meet these new standards without some modifications to the jumper pipe system. Several drop sleeve modifications and numerous boot seal materials and configurations were tested that resulted in limited success in improving the boot seal life. After these modifications, Acme`s testing revealed it could meet the Clean Air Act standards, but it would be cost prohibitive to continue to operate in this manner. Following extensive investigation, Acme decided to install an off-car jumper pipe system which uses a traveling U-tube for connecting to the assist oven through an additional hole in each oven roof. Temperature related failures of drop sleeve seals were eliminated. The off-car jumper pipe is a more efficient gas connection to the assist oven and enables Acme to meet the Clean Air Act charging requirements in a cost effective manner.
NASA Astrophysics Data System (ADS)
Beauclair, N.
The main and subcomponent French suppliers of aircraft tubes and pipes are discussed, and the state of the industry is analyzed. Quality control is essential for tubes with regard to their i.d. and metallurgical compositions. French regulations do not allow welded seam tubes in hydraulic circuits unless no other form is available, and then rustproofed steel must be installed. The actual low level of orders for any run of tubes dictates that the product is only one of several among the manufacturers' line. Automation, both in NDT and quality control, assures that the tubes meet specifications. A total of 10 French companies participate in the industry, serving both civil and military needs, with some companies specializing only in titanium, steel, or aluminum materials. Concerns wishing to enter the market must upgrade their equipment to meet the higher aeronautical specifications and be prepared to furnish tubes and pipes that serve both functional and structural purposes simultaneously. Additionally, pipe-bending machines must also perform to tight specifications. Pipes can range from 0.2 mm exterior diameter to 40 mm, with wall thicknesses from 0.02 mm to 3 mm. A chart containing a list of manufacturers and their respective specifications and characteristics is presented, and a downtrend in production with reduction of personnel is noted.
NASA Astrophysics Data System (ADS)
Drennov, Oleg; Drennov, Andrey; Burtseva, Olga
For connection by welding it is suggested to use the explosive welding method. This method is rather new. Nevertheless, it has become commonly used among the technological developments. This method can be advantageous (saving material and physical resources) comparing to its statical analogs (electron-beam welding, argon-arc welding, plasma welding, gas welding, etc.), in particular, in hard-to-reach areas due to their geographic and climatic conditions. Explosive welding of cylindrical surfaces is performed by launching of welded layer along longitudinal axis of construction. During this procedure, it is required to provide reliable resistance against radial convergent strains. The traditional method is application of fillers of pipe cavity, which are dense cylindrical objects having special designs. However, when connecting pipes consecutively in pipelines by explosive welding, removal of the fillers becomes difficult and sometimes impossible. The suggestion is to use water as filler. The principle of non-compressibility of liquid under quasi-dynamic loading is used. In one-dimensional gasdynamic and elastic-plastic calculations we determined non-deformed mass of water (perturbations, which are moving in the axial direction with sound velocity, should not reach the layer end boundaries for 5-7 circulations of shock waves in the radial direction). Linear dimension of the water layer from the zone of pipe coupling along axis in each direction is >= 2R, where R is the internal radius of pipe.
Fault-tolerant model predictive control of a wind turbine benchmark
Cambridge, University of
Fault-tolerant model predictive control of a wind turbine benchmark X. Yang J.M. Maciejowski tolerant control problem of a wind turbine benchmark. A hierarchical controller with model predictive pre component of the wind turbine. The global MPC is used to schedule the operation of the components
Research on computer systems benchmarking
NASA Technical Reports Server (NTRS)
Smith, Alan Jay (Principal Investigator)
This grant addresses the topic of research on computer systems benchmarking and is more generally concerned with performance issues in computer systems. This report reviews work in those areas during the period of NASA support under this grant. The bulk of the work performed concerned benchmarking and analysis of CPUs, compilers, caches, and benchmark programs. The first part of this work concerned the issue of benchmark performance prediction. A new approach to benchmarking and machine characterization was reported, using a machine characterizer that measures the performance of a given system in terms of a Fortran abstract machine. Another report focused on analyzing compiler performance. The performance impact of optimization in the context of our methodology for CPU performance characterization was based on the abstract machine model. Benchmark programs are analyzed in another paper. A machine-independent model of program execution was developed to characterize both machine performance and program execution. By merging these machine and program characterizations, execution time can be estimated for arbitrary machine/program combinations. The work was continued into the domain of parallel and vector machines, including the issue of caches in vector processors and multiprocessors. All of the afore-mentioned accomplishments are more specifically summarized in this report, as well as those smaller in magnitude supported by this grant.
A Complete Piping Analysis With Thermal Stratification Loads
Milton Dong; Hong Ming Lee; Chii Chern [Bechtel Software, Inc., 50 Beale Street San Francisco, CA 94105-1813 (United States)
The U. S. Nuclear Regulatory Commission (USNRC) had issued Bulletins 88-08, 88-11, 89-90, and 93-38 to address the concerns and problems due to thermal stratification loading during the life span of normal plant operation. The thermal stratification condition typically will cause pipe to bow in on a long horizontal segment. These conditions have not been commonly considered in piping design. However, the additional thermal cyclic stresses and loads due to these conditions could lead to the fatigue damage of the piping components and the failures of pipe supports. Analyzing the effects of thermal stratification loads can be very cumbersome if it is not a built-in functionality of the analysis program. Thus in response to the recent increase in such cases we have incorporated this feature in our piping stress computer program. A stress engineer can now define the thermal stratification conditions easily and the program will compute the pipe stresses and pipe support loads automatically as one of the load cases. The program then combines the thermal stratification load cases with other load cases as required in accordance with the load histogram to determine the cumulative fatigue damage of the piping system. The thermal cyclic stresses are evaluated in accordance with the design rules of Nuclear Class 1 piping components provided in NB-3650 of ASME section III Code. This paper presents the method, modeling and validation for implementing the functionality of analyzing thermal stratification loads in a computer program, as well as an application on an actual piping system as an illustration. (authors)
Implementation of Benchmarking Transportation Logistics Practices and Future Benchmarking Organizations
Thrower, A.W. [U.S. Department of Energy, Office of Civilian Radioactive Waste Management, Washington, DC (United States); Patric, J. [Booz Allen Hamilton, Washington, DC (United States); Keister, M. [Idaho National Laboratory, Idaho Falls, ID (United States)
The purpose of the Office of Civilian Radioactive Waste Management's (OCRWM) Logistics Benchmarking Project is to identify established government and industry practices for the safe transportation of hazardous materials which can serve as a yardstick for design and operation of OCRWM's national transportation system for shipping spent nuclear fuel and high-level radioactive waste to the proposed repository at Yucca Mountain, Nevada. The project will present logistics and transportation practices and develop implementation recommendations for adaptation by the national transportation system. This paper will describe the process used to perform the initial benchmarking study, highlight interim findings, and explain how these findings are being implemented. It will also provide an overview of the next phase of benchmarking studies. The benchmarking effort will remain a high-priority activity throughout the planning and operational phases of the transportation system. The initial phase of the project focused on government transportation programs to identify those practices which are most clearly applicable to OCRWM. These Federal programs have decades of safe transportation experience, strive for excellence in operations, and implement effective stakeholder involvement, all of which parallel OCRWM's transportation mission and vision. The initial benchmarking project focused on four business processes that are critical to OCRWM's mission success, and can be incorporated into OCRWM planning and preparation in the near term. The processes examined were: transportation business model, contract management/out-sourcing, stakeholder relations, and contingency planning. More recently, OCRWM examined logistics operations of AREVA NC's Business Unit Logistics in France. The next phase of benchmarking will focus on integrated domestic and international commercial radioactive logistic operations. The prospective companies represent large scale shippers and have vast experience in safely and efficiently shipping spent nuclear fuel and other radioactive materials. Additional business processes may be examined in this phase. The findings of these benchmarking efforts will help determine the organizational structure and requirements of the national transportation system. (authors)
Piping network model program for small computers
Kruckenberg, N.E.
A model of fluid piping networks was developed to aid in solving problems in the recirculating water coolant system at the Portsmouth Gaseous Diffusion Plant. The piping network model can be used to solve steady state problems in which water flow rates and temperatures are to be determined, or in which temperature is an important factor in determining pressure losses. The model can be implemented on desktop computers to perform these calculations as needed to track changing process conditions. The report includes a description of the coolant system, the mathematical development f the computer model, a case study utilizing the model and a listing and sample run of the computer codes. 2 figs., 1 tab.
Utilizing clad piping to improve process plant piping integrity, reliability, and operations
Chakravarti, B. [KLAD Inc., Naperville, IL (United States)
During the past four years carbon steel piping clad with type 304L (UNS S30403) stainless steel has been used to solve the flow accelerated corrosion (FAC) problem in nuclear power plants with exceptional success. The product is designed to allow ``like for like`` replacement of damaged carbon steel components where the carbon steel remains the pressure boundary and type 304L (UNS S30403) stainless steel the corrosion allowance. More than 3000 feet of piping and 500 fittings in sizes from 6 to 36-in. NPS have been installed in the extraction steam and other lines of these power plants to improve reliability, eliminate inspection program, reduce O and M costs and provide operational benefits. This concept of utilizing clad piping in solving various corrosion problems in industrial and process plants by conservatively selecting a high alloy material as cladding can provide similar, significant benefits in controlling corrosion problems, minimizing maintenance cost, improving operation and reliability to control performance and risks in a highly cost effective manner. This paper will present various material combinations and applications that appear ideally suited for use of the clad piping components in process plants.
Coupling analysis of fluid-structure interaction in fluid-filled elbow pipe
NASA Astrophysics Data System (ADS)
Xu, W. W.; Wu, D. Z.; Wang, L. Q.
Fluid in the ship pipeline, due to power equipment components (such as impellers, plungers, etc.) and valves, will induce turbulence, cavitations, which generate high-frequency vibration excitation lines. The measurements results show that fluid-induced vibration of the pipeline is not only confined to the pipeline, but also have an impact on the hull structure. Pipe vibration due to transient flow is very common in marine pipe system Thus fluid-structure interaction problems in shipping lines is being paid more and more attention. In this paper, the fluid-filled elbow pipe is simulated considering fluid-structure interaction (FSI) by the software ADINA. And the simulation results are validated through comparison with results obtained by other numerical solution. The results show that FSI affects the pipe-filled-water modal frequencies seriously, but have little effects on pipe vibration shapes, and the free vibration frequency of the fluid-filled pipe is lower than that of empty pipe. The pipe vibration amplitude and effective stress caused by fluid increase as the fluid velocity increase. Pipe continues vibrating after fluid velocity is steady, and the vibration is dispersing as time increase. The protection against vibration near the elbow is important because the maximum pipe deformation caused by fluid near the elbow. The maximum effective stress increases from 0 to 1.4MPa due to the fluid velocity increases from 0 to 20m/s in 5 seconds. So it is necessary to consider the FSI for fluid-filled pipe.
Philippe Geuzaine; Kristoer van der Zee; Charbel Farhat
A methodology for designing formally second-order time-accurate and yet loosely coupled partitioned procedures for the solution of nonlinear fluid-structure interac- tion (FSI) problems is presented. Its key components are a fluid time-integrator that is provably second-order time-accurate on moving grids, the midpoint rule for advancing in time the solution of the structural dynamics equations of motion, a second-order structure predictor
Drill pipe protector development
Thomerson, C.; Kenne, R. [Regal International Corp., Corsicanna, TX (United States); Wemple, R.P. [Sandia National Lab., Albuquerque, NM (United States)] [ed.] [and others
The Geothermal Drilling Organization (GDO), formed in the early 1980s by the geothermal industry and the U.S. Department of Energy (DOE) Geothermal Division, sponsors specific development projects to advance the technologies used in geothermal exploration, drilling, and production phases. Individual GDO member companies can choose to participate in specific projects that are most beneficial to their industry segment. Sandia National Laboratories is the technical interface and contracting office for the DOE in these projects. Typical projects sponsored in the past have included a high temperature borehole televiewer, drill bits, muds/polymers, rotary head seals, and this project for drill pipe protectors. This report documents the development work of Regal International for high temperature geothermal pipe protectors.
Pipe inspection using the pipe crawler. Innovative technology summary report
The US Department of Energy (DOE) continually seeks safer and more cost-effective remediation technologies for use in the decontamination and decommissioning (D and D) of nuclear facilities. In several of the buildings at the Fernald Site, there is piping that was used to transport process materials. As the demolition of these buildings occur, disposal of this piping has become a costly issue. Currently, all process piping is cut into ten-foot or less sections, the ends of the piping are wrapped and taped to prevent the release of any potential contaminants into the air, and the piping is placed in roll off boxes for eventual repackaging and shipment to the Nevada Test Site (NTS) for disposal. Alternatives that allow for the onsite disposal of process piping are greatly desired due to the potential for dramatic savings in current offsite disposal costs. No means is currently employed to allow for the adequate inspection of the interior of piping, and consequently, process piping has been assumed to be internally contaminated and thus routinely disposed of at NTS. The BTX-II system incorporates a high-resolution micro color camera with lightheads, cabling, a monitor, and a video recorder. The complete probe is capable of inspecting pipes with an internal diameter (ID) as small as 1.4 inches. By using readily interchangeable lightheads, the same system is capable of inspecting piping up to 24 inches in ID. The original development of the BTX system was for inspection of boiler tubes and small diameter pipes for build-up, pitting, and corrosion. However, the system is well suited for inspecting the interior of most types of piping and other small, confined areas. The report describes the technology, its performance, uses, cost, regulatory and policy issues, and lessons learned.
Glassell, Richard L. (Knoxville, TN); Babcock, Scott M. (Farragut, TN); Lewis, Benjamin E. (Farragut, TN)
A plugging device for closing an opening defined by an end of a pipe with sealant comprises a cap, an extension, an inner seal, a guide, and at least one stop. The cap has an inner surface which defines a chamber adapted for retaining the sealant. The chamber is dimensioned slightly larger than the end so as to receive the end. The chamber and end define a gap therebetween. The extension has a distal end and is attached to the inner surface opposite the distal end. The inner seal is attached to the extension and sized larger than the opening. The guide is positioned forward of the inner seal and attached to the distal end. The guide is also dimensioned to be inserted into the opening. The stop is attached to the extender, and when the stop is disposed in the pipe, the stop is movable with respect to the conduit in one direction and also prevents misalignment of the cap with the pipe. A handle can also be included to allow the cap to be positioned robotically.
Code of Federal Regulations, 2012 CFR
...2012-10-01 2012-10-01 false Piping. 76.33-15 Section 76.33-15...Detecting System, Details � 76.33-15 Piping. (a) Individual pipes shall be not...inch standard pipe size. (b) All piping, valves, and fittings of...
Code of Federal Regulations, 2014 CFR
...2014-10-01 2014-10-01 false Piping. 76.33-15 Section 76.33-15...Detecting System, Details � 76.33-15 Piping. (a) Individual pipes shall be not...inch standard pipe size. (b) All piping, valves, and fittings of...
Code of Federal Regulations, 2013 CFR
...2013-10-01 2013-10-01 false Piping. 76.33-15 Section 76.33-15...Detecting System, Details � 76.33-15 Piping. (a) Individual pipes shall be not...inch standard pipe size. (b) All piping, valves, and fittings of...
Texas at Arlington, University of
Page 1 of 1 Track B Pipe School� Sunday, January 22, 2012 Hilton Palacio Del Rio, San Antonio Selection, Terry McArthur, P.E., HDR, Inc. 9:00 Pipe Materials, Terry McArthur, P.E., HDR, Inc. 9:30 Pipe:15 Principles of Pipeline Design and Construction � Rigid and Flexible Pipes, Shah Rahman, Northwest Pipe
Heat pipe technology: A bibliography with abstracts
NASA Technical Reports Server (NTRS)
The annual supplement on heat pipe technology for 1971 is presented. The document contains 101 references with abstracts and 47 patents. The subjects discussed are: (1) heat pipe applications, (2) heat pipe theory, (3) design, development, and fabrication of heat pipes, (4) testing and operation, (5) subject and author index, and (6) heat pipe related patents.
Research on the ITOC based scheduling system for ship piping production
Rui Li; Yu-Jun Liu; Kunihiro Hamada
Manufacturing of ship piping systems is one of the major production activities in shipbuilding. The schedule of pipe production\\u000a has an important impact on the master schedule of shipbuilding. In this research, the ITOC concept was introduced to solve\\u000a the scheduling problems of a piping factory, and an intelligent scheduling system was developed. The system, in which a product\\u000a model,
Development of a theory of constraints based scheduling system for ship piping production
Rui Li; Kunihiro Hamada; Takahiro Shimozori
Manufacturing of ship piping system is one of the major production activities in shipbuilding. The schedule of pipe production\\u000a has an important impact on master schedule of shipbuilding. In this research, the theory of constraints (TOC) concept is introduced\\u000a to solve the scheduling problems of piping factory, and an intelligent scheduling system is developed. The system integrates\\u000a a product model,
In vacuum thermal characteristics of different geometry sodium heat pipes
NASA Astrophysics Data System (ADS)
Fujiwara, Tsutomu; Ogiwara, Sachio; Nakamura, Yoshihiro; Eguchi, Kunihisa
An experimental investigation is presently under way at the National Aerospace Laboratory (NAL) to provide understanding of high temperature heat pipe (HP) operations in space that are capable of transferring thermal energy from a solar receiver to a Stirling engine. To design a high performance heat pipe, it is necessary to assess accurately fundamental physical phenomena during the HP operations. In considering the heat pipe integration with a Stirling engine heater head, however, we are facing some problems of the HP design involved in the complex structure. Additionally, in such HP operations, the heat input distribution might be non-uniform and the liquid sodium return flow will be blocked at the connecting part of the wick. This will result in reduction of the heat transfer capability. To overcome such an operational problem, we have designed and tested two different types of heat pipe models. One is a T-shaped heat pipe and another is a cavity type, both having adiabatic and condenser parts of a single straight pipe. In the present paper, some experimental results available from these heating tests in a vacuum chamber are described.
DOE Commercial Building Benchmark Models
Torcellini, P.; Deru, M.; Griffith, B.; Benne, K.; Halverson, M.; Winiarski, D.; Crawley, D.
The excitement surrounding the drive to build and renovate commercial buildings to achieve exemplary and even 'net zero performance,' coupled with the realization that complex systems engineering is usually required to achieve such levels, has led to a broader use of computer energy simulations. To provide a consistent baseline of comparison and save time conducting such simulations, the U.S. Department of Energy (DOE) - through three of its national laboratories - has developed a set of standard benchmark building models for new and existing buildings. These models represent a complete revision of the DOE benchmark buildings originally developed in 2006. The shapes, thermal zoning, and operation of the models are more indicative of real buildings than in the previous versions. DOE has developed 15 benchmark buildings that represent most of the commercial building stock, across 16 locations (representing all U.S. climate zones) and with three vintages (new, pre-1980, and post-1980 construction). This paper will provide an executive summary overview of these benchmark buildings, and how they can save building analysts valuable time. Fully documented and implemented to use with the EnergyPlus energy simulation program, the benchmark models are publicly available and new versions will be created to maintain compatibility with new releases of EnergyPlus. The benchmark buildings will form the basis for research on specific building technologies, energy code development, appliance standards, and measurement of progress toward DOE energy goals. Having a common starting point allows us to better share and compare research results and move forward to make more energy efficient buildings.
Sustainable value assessment of farms using frontier efficiency benchmarks.
Van Passel, Steven; Van Huylenbroeck, Guido; Lauwers, Ludwig; Mathijs, Erik
Appropriate assessment of firm sustainability facilitates actor-driven processes towards sustainable development. The methodology in this paper builds further on two proven methodologies for the assessment of sustainability performance: it combines the sustainable value approach with frontier efficiency benchmarks. The sustainable value methodology tries to relate firm performance to the use of different resources. This approach assesses contributions to corporate sustainability by comparing firm resource productivity with the resource productivity of a benchmark, and this for all resources considered. The efficiency is calculated by estimating the production frontier indicating the maximum feasible production possibilities. In this research, the sustainable value approach is combined with efficiency analysis methods to benchmark sustainability assessment. In this way, the production theoretical underpinnings of efficiency analysis enrich the sustainable value approach. The methodology is presented using two different functional forms: the Cobb-Douglas and the translog functional forms. The simplicity of the Cobb-Douglas functional form as benchmark is very attractive but it lacks flexibility. The translog functional form is more flexible but has the disadvantage that it requires a lot of data to avoid estimation problems. Using frontier methods for deriving firm specific benchmarks has the advantage that the particular situation of each company is taken into account when assessing sustainability. Finally, we showed that the methodology can be used as an integrative sustainability assessment tool for policy measures. PMID:19553001
Probability of failure in BWR reactor coolant piping: Probabilistic treatment of stress corrosion cracking in 304 and 316NG BWR piping weldments
Harris, D.O.; Dedhia, D.D.; Eason, E.D.; Patterson, S.D.
The purpose of this report is to describe recent expansions of the previously developed PRAISE code to include recent information to make it more applicable to probabilistic analysis of sensitized weldments in BWR piping. The expansions of PRAISE are concentrated in three areas: (1) probabilistic treatment of stress corrosion crack initiation in 304 and 316NG; (2) probabilistic treatment of residual stresses; and (3) benchmarking with field observations of cracking in 304 BWR piping weldments. This expanded version of PRAISE is called PRAISE-CC, and is a significant extension of earlier versions, which considered only piping failures due to the growth of pre-existing crack-like weld defects. PRAISE-CC retains the earlier PRAISE capabilities.
Lindsey, H.E.; Cole, P.W.
This patent describes a method of cementing a linear in a well bore. It comprises: making up sections of pipe to form a liner disposed in a well bore to a desired length of liner, supporting the desired length of liner at the earth's surface while making up sections of drill pipe to form a desired string of drill pip co-axially disposed within the desired length of liner where the desired string of drill pipe has a polished mandrel and a sealing bore receptacle at its lower end when the polished mandrel is in position for sealing reception in the sealing bore receptacle, attaching a setting tool assembly to the desired string of drill pipe and attaching a liner hanger assembly with liner hanger slips to the desired length of liner; releasing the liner at the earth's surface and making up a supporting string of drill pipe attached to the setting tool assembly for lowering the co-axially disposed (telescoped) desired length of liner and string of drill pipe through the well bore hanging the liner in the well bore with liner hanger slips; pumping a volume of cement slurry through the supporting string of drill pipe; and upon the trailing end of the volume of cement slurry reaching the lower end of the desired string of drill pipe, opening the interior of the desired string of drill pipe to the interior of the liner at a location above the sealing bore receptacle.
Cryogenic Heat Pipe Experiment (CRYOHP)
NASA Astrophysics Data System (ADS)
McIntosh, Roy
The objective of the CRYOHP experiment is to conduct a shuttle experiment that demonstrates the reliable operation of two oxygen heat pipes in microgravity. The experiment will perform the following tasks: (1) demonstrate startup of the pipes from the supercritical state; (2) measure the heat transport capacity of the pipes; (3) measure evaporator and condenser film coefficients; and (4) work shuttle safety issues. The approach for the experiment is as follows: (1) fly two axially grooved oxygen heat pipes attached to mechanical stirling cycle tactical coolers; (2) integrate experiment in hitch-hiker canister; and (3) fly on shuttle and control from ground.
14 CFR 25.1123 - Exhaust piping.
Code of Federal Regulations, 2014 CFR
... � 25.1123 Exhaust piping. For powerplant and...apply: (a) Exhaust piping must be heat and corrosion...have provisions to prevent failure due to expansion by operating temperatures. (b) Piping must be supported to...
14 CFR 27.1123 - Exhaust piping.
Code of Federal Regulations, 2013 CFR
...System � 27.1123 Exhaust piping. (a) Exhaust piping must be heat and corrosion resistant...must have provisions to prevent failure due to expansion by operating temperatures. (b) Exhaust piping must be supported to...
14 CFR 29.1123 - Exhaust piping.
Code of Federal Regulations, 2012 CFR
...System � 29.1123 Exhaust piping. (a) Exhaust piping must be heat and corrosion resistant...must have provisions to prevent failure due to expansion by operating temperatures. (b) Exhaust piping must be supported to...
14 CFR 29.1123 - Exhaust piping.
Code of Federal Regulations, 2013 CFR
...System � 29.1123 Exhaust piping. (a) Exhaust piping must be heat and corrosion resistant...must have provisions to prevent failure due to expansion by operating temperatures. (b) Exhaust piping must be supported to...
14 CFR 25.1123 - Exhaust piping.
Code of Federal Regulations, 2013 CFR
... � 25.1123 Exhaust piping. For powerplant and...apply: (a) Exhaust piping must be heat and corrosion...have provisions to prevent failure due to expansion by operating temperatures. (b) Piping must be supported to...
14 CFR 27.1123 - Exhaust piping.
Code of Federal Regulations, 2014 CFR
...System � 27.1123 Exhaust piping. (a) Exhaust piping must be heat and corrosion resistant...must have provisions to prevent failure due to expansion by operating temperatures. (b) Exhaust piping must be supported to...
14 CFR 29.1123 - Exhaust piping.
Code of Federal Regulations, 2014 CFR
...System � 29.1123 Exhaust piping. (a) Exhaust piping must be heat and corrosion resistant...must have provisions to prevent failure due to expansion by operating temperatures. (b) Exhaust piping must be supported to...
14 CFR 27.1123 - Exhaust piping.
Code of Federal Regulations, 2012 CFR
...System � 27.1123 Exhaust piping. (a) Exhaust piping must be heat and corrosion resistant...must have provisions to prevent failure due to expansion by operating temperatures. (b) Exhaust piping must be supported to...
14 CFR 25.1123 - Exhaust piping.
Code of Federal Regulations, 2012 CFR
... � 25.1123 Exhaust piping. For powerplant and...apply: (a) Exhaust piping must be heat and corrosion...have provisions to prevent failure due to expansion by operating temperatures. (b) Piping must be supported to...
Benchmarking Parallel Java Master's Project Report
Kaminsky, Alan
................................................................ 3 3.1. Core Parallel Java Constructs Benchmarking Parallel Java Master's Project Report Asma'u Sani Mohammed Java API by implementing the OpenMP version of the NAS Parallel Benchmark (NPB
Deterministic Random Number Generator Benchmarks
Deterministic Random Number Generator Benchmarks By Karl Lopker Introduction Deterministic Random to generate its numbers. The DevRandom class is also secure. It gets its numbers from the Linux /dev/random Number Generators (DRNGs) are important for a wide variety of applications. However, all languages
BYBLOS Speech Recognition Benchmark Results
Francis Kubala; Steve Austin; Chris Barry; John Makhoul; P. Placeway; Richard M. Schwartz
This paper presents speech recognition test results from the BBN BYBLOS system on the Feb 91 DARPA benchmarks in both the Resource Management (RM) and the Air Travel Information System (ATIS) domains. In the RM test, we report on speaker-independent (SI) recognition performance for the standard training condition using 109 speakers and for our recently proposed SI model made from
Benchmark Lisp And Ada Programs
NASA Technical Reports Server (NTRS)
Davis, Gloria; Galant, David; Lim, Raymond; Stutz, John; Gibson, J.; Raghavan, B.; Cheesema, P.; Taylor, W.
Suite of nonparallel benchmark programs, ELAPSE, designed for three tests: comparing efficiency of computer processing via Lisp vs. Ada; comparing efficiencies of several computers processing via Lisp; or comparing several computers processing via Ada. Tests efficiency which computer executes routines in each language. Available for computer equipped with validated Ada compiler and/or Common Lisp system.
Using Benchmarks to Compare Fractions
NSDL National Science Digital Library
IInstitute for Mathematics & amp; Education funded by the Bill & amp; Melinda Gates Foundation
This task is intended primarily for instruction purposes. The goal is to provide examples for comparing two fractions. This is an important method for comparing fractions and one which requires a strong number sense and ability to make mental calculations. It is, however, a difficult ability to assess because the method is only appropriate when there is a clear benchmark fraction to be used.
Coding changes could affect benchmarking.
CMS intends to move to a severity-adjusted system for DRGs; number of codes may double. ICD-10 will allow for more specific codes, which could affect benchmark data. Understanding the new codes and data will be critical to uncovering opportunities for improvement. PMID:16925073
Simple mathematical law benchmarks human confrontations.
Johnson, Neil F; Medina, Pablo; Zhao, Guannan; Messinger, Daniel S; Horgan, John; Gill, Paul; Bohorquez, Juan Camilo; Mattson, Whitney; Gangi, Devon; Qi, Hong; Manrique, Pedro; Velasquez, Nicolas; Morgenstern, Ana; Restrepo, Elvira; Johnson, Nicholas; Spagat, Michael; Zarama, Roberto
Many high-profile societal problems involve an individual or group repeatedly attacking another - from child-parent disputes, sexual violence against women, civil unrest, violent conflicts and acts of terror, to current cyber-attacks on national infrastructure and ultrafast cyber-trades attacking stockholders. There is an urgent need to quantify the likely severity and timing of such future acts, shed light on likely perpetrators, and identify intervention strategies. Here we present a combined analysis of multiple datasets across all these domains which account for >100,000 events, and show that a simple mathematical law can benchmark them all. We derive this benchmark and interpret it, using a minimal mechanistic model grounded by state-of-the-art fieldwork. Our findings provide quantitative predictions concerning future attacks; a tool to help detect common perpetrators and abnormal behaviors; insight into the trajectory of a 'lone wolf'; identification of a critical threshold for spreading a message or idea among perpetrators; an intervention strategy to erode the most lethal clusters; and more broadly, a quantitative starting point for cross-disciplinary theorizing about human aggression at the individual and group level, in both real and online worlds. PMID:24322528
Simple mathematical law benchmarks human confrontations
Johnson, Neil F.; Medina, Pablo; Zhao, Guannan; Messinger, Daniel S.; Horgan, John; Gill, Paul; Bohorquez, Juan Camilo; Mattson, Whitney; Gangi, Devon; Qi, Hong; Manrique, Pedro; Velasquez, Nicolas; Morgenstern, Ana; Restrepo, Elvira; Johnson, Nicholas; Spagat, Michael; Zarama, Roberto
Many high-profile societal problems involve an individual or group repeatedly attacking another � from child-parent disputes, sexual violence against women, civil unrest, violent conflicts and acts of terror, to current cyber-attacks on national infrastructure and ultrafast cyber-trades attacking stockholders. There is an urgent need to quantify the likely severity and timing of such future acts, shed light on likely perpetrators, and identify intervention strategies. Here we present a combined analysis of multiple datasets across all these domains which account for >100,000 events, and show that a simple mathematical law can benchmark them all. We derive this benchmark and interpret it, using a minimal mechanistic model grounded by state-of-the-art fieldwork. Our findings provide quantitative predictions concerning future attacks; a tool to help detect common perpetrators and abnormal behaviors; insight into the trajectory of a �lone wolf'; identification of a critical threshold for spreading a message or idea among perpetrators; an intervention strategy to erode the most lethal clusters; and more broadly, a quantitative starting point for cross-disciplinary theorizing about human aggression at the individual and group level, in both real and online worlds. PMID:24322528
DeWitt: Wisconsin Benchmark 1 Second Draft The Wisconsin Benchmark: Past, Present, and Future
Narasayya, Vivek
DeWitt: Wisconsin Benchmark 1 Second Draft The Wisconsin Benchmark: Past, Present, and Future David J. DeWitt Computer Sciences Department University of Wisconsin 1.0. Introduction In 1981 as we were as the Wisconsin Benchmark [BITT83]. The benchmark was designed with two objectives in mind. First, the queries
Verification Benchmarks to Assess the Implementation of Computational Fluid Dynamics Based Hemolysis Prediction Models.
Hariharan, Prasanna; D'Souza, Gavin; Horner, Marc; Malinauskas, Richard A; Myers, Matthew R
As part of an ongoing effort to develop verification and validation (V&V) standards for using computational fluid dynamics (CFD) in the evaluation of medical devices, we have developed idealized flow-based verification benchmarks to assess the implementation of commonly cited power-law based hemolysis models in CFD. Verification process ensures that all governing equations are solved correctly and the model is free of user and numerical errors. To perform verification for power-law based hemolysis modeling, analytical solutions for the Eulerian power-law blood damage model (which estimates hemolysis index (HI) as a function of shear stress and exposure time) were obtained for Couette and inclined Couette flow models, and for Newtonian and non-Newtonian pipe flow models. Subsequently, CFD simulations of fluid flow and HI were performed using Eulerian and three different Lagrangian-based hemolysis models and compared with the analytical solutions. For all the geometries, the blood damage results from the Eulerian-based CFD simulations matched the Eulerian analytical solutions within ?1%, which indicates successful implementation of the Eulerian hemolysis model. Agreement between the Lagrangian and Eulerian models depended upon the choice of the hemolysis power-law constants. For the commonly used values of power-law constants (? ?=?1.9-2.42 and ? ?=?0.65-0.80), in the absence of flow acceleration, most of the Lagrangian models matched the Eulerian results within 5%. In the presence of flow acceleration (inclined Couette flow), moderate differences (?10%) were observed between the Lagrangian and Eulerian models. This difference increased to greater than 100% as the beta exponent decreased. These simplified flow problems can be used as standard benchmarks for verifying the implementation of blood damage predictive models in commercial and open-source CFD codes. The current study only used power-law model as an illustrative example to emphasize the need for model verification. Similar verification problems could be developed for other types of hemolysis models (such as strain-based and energy dissipation-based methods). However, since the current study did not include experimental validation, the results from the verified models do not guarantee accurate hemolysis predictions. This verification step must be followed by experimental validation before the hemolysis models can be used for actual device safety evaluations. PMID:26065371
Protein models docking benchmark 2.
Anishchenko, Ivan; Kundrotas, Petras J; Tuzikov, Alexander V; Vakser, Ilya A
Structural characterization of protein-protein interactions is essential for our ability to understand life processes. However, only a fraction of known proteins have experimentally determined structures. Such structures provide templates for modeling of a large part of the proteome, where individual proteins can be docked by template-free or template-based techniques. Still, the sensitivity of the docking methods to the inherent inaccuracies of protein models, as opposed to the experimentally determined high-resolution structures, remains largely untested, primarily due to the absence of appropriate benchmark set(s). Structures in such a set should have predefined inaccuracy levels and, at the same time, resemble actual protein models in terms of structural motifs/packing. The set should also be large enough to ensure statistical reliability of the benchmarking results. We present a major update of the previously developed benchmark set of protein models. For each interactor, six models were generated with the model-to-native C(?) RMSD in the 1 to 6 � range. The models in the set were generated by a new approach, which corresponds to the actual modeling of new protein structures in the "real case scenario," as opposed to the previous set, where a significant number of structures were model-like only. In addition, the larger number of complexes (165 vs. 63 in the previous set) increases the statistical reliability of the benchmarking. We estimated the highest accuracy of the predicted complexes (according to CAPRI criteria), which can be attained using the benchmark structures. The set is available at http://dockground.bioinformatics.ku.edu. PMID:25712716
Dhrystone: a synthetic systems programming benchmark
Reinhold P. Weicker
Reflecting current data on the use of programming language constructs in systems programming, a synthetic benchmark is constructed based on the distribution appearing in the data. The benchmark executes 100 Ada statements that are balanced in terms of the distribution of statement types, data types, and data locality. Pascal and C versions of the benchmark are discussed.
The DARPA image understanding motion benchmark
Charles Weems; Steven Dropsho; Glen Weaver; Rohan Kumar; James Burrill
Benchmarks and test suites are an essential element of the architectural evaluation process. At the conclusion of the last DARPA workshop on vision benchmarks to test the performance of parallel architectures, it was recommended that the DARPA Image Understanding Benchmark be extended with a second level task to add motion and tracking to the original task. We have now developed
The Case for Application-Specific Benchmarking
Margo I. Seltzer; David Krinsky; Keith A. Smith; Xiaolan Zhang
Most performance analysis today uses either microbenchmarks or standard macrobenchmarks (e.g. SPEC, LADDIS, the Andrew benchmark). However, the results of such benchmarks provide little information to indicate how well a particular system will handle a particular application. Such results are, at best, useless and, at worst, misleading. In this paper we argue for an application-directed approach to benchmarking, using performance
BESP � benchmarking of Portuguese secondary schools
Maria Concei��o A. Silva Portela; Ana Santos Camanho; Diogo N�voa Borges
Purpose � The purpose of this paper is to illustrate the implementation of a web-based platform integrating benchmarking and data envelopment analysis (DEA) for the Portuguese secondary schools. Design\\/methodology\\/approach � The benchmarking platform is designed around a set of key performance indicators that are displayed using benchmarking graphs. These indicators are also aggregated through the methodology of DEA to provide
How Benchmarking and Higher Education Came Together
ERIC Educational Resources Information Center
Levy, Gary D.; Ronco, Sharron L.
This chapter introduces the concept of benchmarking and how higher education institutions began to use benchmarking for a variety of purposes. Here, benchmarking is defined as a strategic and structured approach whereby an organization compares aspects of its processes and/or outcomes to those of another organization or set of organizations to�
Ontology matching benchmarks: generation, stability, and discriminability$
Paris-Sud XI, Universit� de
Ontology matching benchmarks: generation, stability, and discriminability$ J�r�me Euzenata, , Maria Benchmark test set has been used for many years as a main reference to evaluate and compare ontology ontologies and different alteration modalities. It has been used for reproducing Benchmark both
On the problem of turbulent flows in pipes at very large Reynolds numbers (reply to comment by I�I�Vigdorovich [Phys. Usp. 58 196 (2015); Usp. Fiz. Nauk 185 213 (2015)] on "Turbulent flows at very large Reynolds numbers: new lessons learned" [Phys. Usp. 57 250 (2014); Usp. Fiz. Nauk 184 265 (2014)])
NASA Astrophysics Data System (ADS)
Barenblatt, G. I.; Chorin, A. J.; Prostokishin, V. M.
The problem of turbulent flow in pipes, although at first sight of purely engineering interest, has since the 1930s been the subject of much attention by mathematicians and physicists, including such outstanding figures as Th von K�rm�n, L Prandtl, and L D Landau. It has turned out that despite � or perhaps due to � the seemingly simple formulation of this problem, research on it has revealed new aspects of the still very mysterious phenomenon of turbulence. Reference [1] briefly summarizes our work over the last twenty years on the problem. Some of our results strongly disagree with commonly accepted views which, unsurprisingly, makes them difficult to accept. This is well exemplified by letter [2], so its analysis here may hopefully be of interest to UFN's (Physics -Uspekhi) readers.
Dynamic stability of a pipe conveying fluid with an uncertain computational model
Paris-Sud XI, Universit� de
Dynamic stability of a pipe conveying fluid with an uncertain computational model T. G. Rittoa , C in the computational model. The aim of this work is twofold: (1) to propose a probabilistic model for the fluid deals with the problem of a pipe conveying fluid of interest in several engineering applications
Iron release from corroded iron pipes in drinkingwater distribution systems: effect of dissolved oxygen
P. Sarina; V. L. Snoeyink; J. Bebee; K. K. Jim; W. M. Krivena Beckett; J. A. Clement
Iron release from corroded iron pipes is the principal cause of ''colored water'' problems in drinkingwater distribution systems. The corrosion scales present in corroded iron pipes restrict the flow of water, and can also deteriorate the water quality. This research was focused on understandingthe effect of dissolved oxyg en (DO), a key water quality parameter, on iron release from the
Internal erosion during soil pipe flow: Role in gully erosion and hillslope instability
Technology Transfer Automated Retrieval System (TEKTRAN)
Many field observations have lead to speculation on the role of piping in embankment failures, landslides, and gully erosion. However, there has not been a consensus on the subsurface flow and erosion processes involved and inconsistent use of terms have exasperated the problem. One such piping proc...
NASA Astrophysics Data System (ADS)
Simitsis, Alkis; Vassiliadis, Panos; Dayal, Umeshwar; Karagiannis, Anastasios; Tziovara, Vasiliki
Extraction-Transform-Load (ETL) processes comprise complex data workflows, which are responsible for the maintenance of a Data Warehouse. A plethora of ETL tools is currently available constituting a multi-million dollar market. Each ETL tool uses its own technique for the design and implementation of an ETL workflow, making the task of assessing ETL tools extremely difficult. In this paper, we identify common characteristics of ETL workflows in an effort of proposing a unified evaluation method for ETL. We also identify the main points of interest in designing, implementing, and maintaining ETL workflows. Finally, we propose a principled organization of test suites based on the TPC-H schema for the problem of experimenting with ETL workflows.
Heat Pipe Thermal Conditioning Panel
NASA Technical Reports Server (NTRS)
Saaski, E. W.
The development, fabrication, and evaluation of heat pipe thermal conditioning panels are discussed. The panels were designed and fabricated to be compatible with several planned NASA space vehicles, in terms of panel size, capacity, temperature gradients, and integration with various heat exchangers and electronic components. It was satisfactorily demonstrated that the heat pipe thermal conditioning panel meets the thermal efficiency and heat transport requirements.
Alternate high capacity heat pipe
NASA Technical Reports Server (NTRS)
Voss, F. E.
The performance predictions for a fifty foot heat pipe (4 foot evaporator - 46 foot condensor) are discussed. These performance predictions are supported by experimental data for a four foot heat pipe. Both heat pipes have evaporators with axial groove wick structures and condensers with powder metal external artery wick structures. The predicted performance of a rectangular axial groove/external artery heat pipe operating in space is given. Heat transport versus groove width is plotted for 100, 200 and 300 grooves in the evaporator. The curves show that maximum power is achieved for groove widths from 0.040 to 0.053 as the number of grooves varies from 300 to 100. The corresponding range of maximum power is 3150 to 2400 watts. The relationships between groove width and heat pipe evaporate diameter for 100, 200 and 300 grooves in the evaporator are given. A four foot heat pipe having a three foot condenser and one foot evaporator was built and tested. The evaporator wick structure used axial grooves with rectangular cross sections, and the condenser wick structure used powder metal with an external artery configuration. Fabrication drawings are enclosed. The predicted and measured performance for this heat pipe is shown. The agreement between predicted and measured performance is good and therefore substantiates the predicted performance for a fifty foot heat pipe.
Composite material heat pipe radiator
Nelson J. Gernert; David B. Sarraf; Richard J. Guenther
Organic matrix composite material is recognized for its significant strength to weight ratio when compared to metal and consequently was investigated for reducing the mass of heat pipes for future space missions. The particular heat pipe that was constructed and tested was made from an organic matrix composite material applied to a linear of titanium tubing spun to foil thickness
Building a Copper Pipe "Xylophone."
ERIC Educational Resources Information Center
Lapp, David R.
Explains how to use the equation for frequency of vibration of a transversely oscillating bar or pipe with both ends free to vibrate to build a simple and inexpensive xylophone from a 3-meter section of copper pipe. The instrument produces a full major scale and can be used to investigate various musical intervals. (Author/NB)
Automatic Piping System in Ship
Ubald Nienhuis
One of the most complicated and time-consuming process in ship production is to determine the optimum route of piping. The automatic system to generate optimum collision free routes for pipes is presented in this paper. In the past, research has been primarily focused on the use of only deterministic or only nondeterministic optimization techniques to find the optimal route. In
Demonstrating Sound Impulses in Pipes.
ERIC Educational Resources Information Center
Raymer, M. G.; Micklavzina, Stan
Describes a simple, direct method to demonstrate the effects of the boundary conditions on sound impulse reflections in pipes. A graphical display of the results can be made using a pipe, cork, small hammer, microphone, and fast recording electronics. Explains the principles involved. (LZ)
Generator cooling using heat pipes
Bert de LEEUW; Harry Hagens; Brand van den S; Mart Grooten; FLA Ganzevles; Geld van der CWM; Kemenade van HP
This paper presents the study of a heat pipe- equipped heat exchanger with two filling ratios of R134a 19 % and 59 %, respectively. The airflow rate varies from 0.4 to 2.0 kg\\/ s. The temperatures at the evaporator side of the heat pipe vary from 40 to 70 �C and at the condenser part from 20 to 50 �C.
Methods of jointing ceramic pipes
I. I. Arkhipov; Z. O. Nemchenok
In Czechoslovakia the ceramic pipes are jointed with the help of rubber sealing rings. The rings have a reinforced core and two internal flaps. In the cuff of the ring a steel reinforcement is pressed which hinders its deformation during mounting. The ring has a conical shape and when installed in the neck of a pipe, it clamps by itself.
Hunt, A.
This patent describes a full bore, multi-phase fluid flowmeter having no internal obstructions. It comprises: a first section of pipe with a first diameter; a second section of pipe with a second diameter less than the first diameter; a third section of pipe intermediate and connecting the first and second pipe sections and having a smoothly and gradually changing diameter from the first diameter to the second diameter; a first pressure sensor positioned in the neighborhood of the start of the change of diameter of the third section of pipe from the first diameter to the second diameter; a second pressure sensor in the first section of pipe spaced in one direction from the first pressure sensor; and a third pressure sensor spaced in the other direction from the first pressure sensor. The density of the fluid flowing through the pipe obtained from a differential pressure measurement made between the first and second pressure sensors is combined with the flow rate of the fluid flowing through the pipe sections obtained from the density value and a second differential pressure measurement made between the first and third pressure sensors to obtain a multi-phase fluid flow determination compensated for phase slippage and friction pressure losses.
J. P. Sellers
Analysis of the data heat pipe radiator systems tested in both vacuum and ambient environments was continued. The systems included (1) a feasibility VCHP header heat-pipe panel, (2) the same panel reworked to eliminate the VCHP feature and referred to as the feasibility fluid header panel, and (3) an optimized flight-weight fluid header panel termed the 'prototype.' A description of
Heat pipe technology quarterly literature review. Volume 1, Number 3
R. Srinivasan; R. W. Gonzales
A bibliography containing 110 citations is presented. The citations are arranged in five sections on general information on heat pipes, heat pipe applications, heat pipe theory, heat pipe design, development, and fabrication, and heat pipe testing and operation.
Finite element analysis of fluid-filled elastic piping systems
NASA Technical Reports Server (NTRS)
Everstine, G. C.; Marcus, M. S.; Quezon, A. J.
Two finite element procedures are described for predicting the dynamic response of general 3-D fluid-filled elastic piping systems. The first approach, a low frequency procedure, models each straight pipe or elbow as a sequence of beams. The contained fluid is modeled as a separate coincident sequence axial members (rods) which are tied to the pipe in the lateral direction. The model includes the pipe hoop strain correction to the fluid sound speed and the flexibility factor correction to the elbow flexibility. The second modeling approach, an intermediate frequency procedure, follows generally the original Zienkiewicz-Newton scheme for coupled fluid-structure problems except that the velocity potential is used as the fundamental fluid unknown to symmetrize the coefficient matrices. From comparisons of the beam model predictions to both experimental data and the 3-D model, the beam model is validated for frequencies up to about two-thirds of the lowest fluid-filled labor pipe mode. Accurate elbow flexibility factors are seen to be crucial for effective beam modeling of piping systems.
An investigation of corrosion in liquid-metal heat pipes
Adkins, D.R.; Rawlinson, K.S.; Andraka, C.E.; Showalter, S.K.; Moreno, J.B.; Moss, T.A.; Cordiero, P.G.
Research is underway to develop a 75-kW heat pipe to transfer solar energy from the focus of a parabolic dish concentrator to the heater tubes of a Stirling engine. The high flux levels and high total power level encountered in this application have made it necessary to use a high-performance wick structure with fibers on the order of 4 to 8 microns in diameter. This fine wick structure is highly susceptible to corrosion damage and plugging, as dissolved contaminants plate out on the evaporator surface. Normal operation of the heat pipe also tends to concentrate contaminants in localized areas of the evaporator surface where heat fluxes are the highest. Sandia National Laboratories is conducting a systematic study to identify procedures that reduce corrosion and contamination problems in liquid-metal heat pipes. A series of heat pipes are being tested to explore different options for cleaning heat-pipe systems. Models are being developed to help understand the overall importance of operating parameters on the life of heat-pipe systems. In this paper, the authors present their efforts to reduce corrosion damage.
Study of elbow effect on pulsation in piping system
Miyano, Hiroshi; Saito, Noboru; Hagiwara, Tsuyoshi [Toshiba Corp., Kawasaki, Kanagawa (Japan). Nuclear Engineering Lab.
BWR (Boiling Water Reactor) had recirculation pumps, which are centrifugal type. They generate pressure pulsation by vane passing. Pulsation is one of the important causes of vibration. It is a common problem in piping system. In order to predict vibration of piping system, the authors to know or predict the distribution of pulsation amplitude. They measured the distribution in a simple piping system, which consists of straight pipes, elbows, a tank and a pump. In this system the pulsation was generated by the pump`s vane passing. Pulsation wave reflected at pipe end and formed standing wave. It is conventionally said that the standing wave is sinusoidal and that the phase does not change at straight pipes and elbows. However the authors measured discrepancy from conventional theory at elbows. The amplitude and phase changed discontinuously at elbows. When one locates at loop of standing wave, the discrepancy is large. The authors considered that it is caused by partial reflection at elbow and calculated the distribution taking this effect into account. They obtained good agreement with the calculation and the measurement.
Bianchini, G.M.; McRae, T.G.
The invention is a method and apparatus for continually monitoring the composition of liquefied natural gas flowing from a spill pipe during a spill test by continually removing a sample of the LNG by means of a probe, gasifying the LNG in the probe, and sending the vaporized LNG to a remote ir gas detector for analysis. The probe comprises three spaced concentric tubes surrounded by a water jacket which communicates with a flow channel defined between the inner and middle, and middle and outer tubes. The inner tube is connected to a pump for providing suction, and the probe is positioned in the LNG flow below the spill pipe with the tip oriented partly downward so that LNG is continuously drawn into the inner tube through a small orifice. The probe is made of a high thermal conductivity metal. Hot water is flowed through the water jacket and through the flow channel between the three tubes to provide the necessary heat transfer to flash vaporize the LNG passing through the inner channel of the probe. The gasified LNG is transported through a connected hose or tubing extending from the probe to a remote ir sensor which measures the gas composition.
NASA Astrophysics Data System (ADS)
Bianchini, G. M.; McRae, T. G.
The invention is a method and apparatus for continually monitoring the composition of liquefied natural gas flowing from a spill pipe during a spill test by continually removing a sample of the LNG by means of a probe, gasifying the LNG in the probe, and sending the vaporized LNG to a remote IR gas detector for analysis. The probe comprises three spaced concentric tubes surrounded by a water jacket which communicates with a flow channel defined between the inner and middle, and middle and outer tubes. The inner tube is connected to a pump for providing suction, and the probe is positioned in the LNG flow below the spill pipe with the tip oriented partly downward so that LNG is continuously drawn into the inner tube through a small orifice. The probe is made of a high thermal conductivity metal. Hot water is flowed through the water jacket and through the flow channel between the three tubes to provide the necessary heat transfer to flash vaporize the LNG passing through the inner channel of the probe. The gasified LNG is transported through a connected hose or tubing extending from the probe to a remote IR sensor which measures the gas composition.
Flexible ultrasonic pipe inspection apparatus
Jenkins, Charles F. (Aiken, SC); Howard, Boyd D. (Augusta, GA)
A flexible, modular ultrasonic pipe inspection apparatus, comprising a flexible, hollow shaft that carries a plurality of modules, including at least one rotatable ultrasonic transducer, a motor/gear unit, and a position/signal encoder. The modules are connected by flexible knuckle joints that allow each module of the apparatus to change its relative orientation with respect to a neighboring module, while the shaft protects electrical wiring from kinking or buckling while the apparatus moves around a tight corner. The apparatus is moved through a pipe by any suitable means, including a tether or drawstring attached to the nose or tail, differential hydraulic pressure, or a pipe pig. The rotational speed of the ultrasonic transducer and the forward velocity of the apparatus are coordinated so that the beam sweeps out the entire interior surface of the pipe, enabling the operator to accurately assess the condition of the pipe wall and determine whether or not leak-prone corrosion damage is present.
Promethus Hot Leg Piping Concept
AM Girbik; PA Dilorenzo
The Naval Reactors Prime Contractor Team (NRPCT) recommended the development of a gas cooled reactor directly coupled to a Brayton energy conversion system as the Space Nuclear Power Plant (SNPP) for NASA's Project Prometheus. The section of piping between the reactor outlet and turbine inlet, designated as the hot leg piping, required unique design features to allow the use of a nickel superalloy rather than a refractory metal as the pressure boundary. The NRPCT evaluated a variety of hot leg piping concepts for performance relative to SNPP system parameters, manufacturability, material considerations, and comparison to past high temperature gas reactor (HTGR) practice. Manufacturability challenges and the impact of pressure drop and turbine entrance temperature reduction on cycle efficiency were discriminators between the piping concepts. This paper summarizes the NRPCT hot leg piping evaluation, presents the concept recommended, and summarizes developmental issues for the recommended concept.
HS06 Benchmark for an ARM Server
NASA Astrophysics Data System (ADS)
Kluth, Stefan
We benchmarked an ARM cortex-A9 based server system with a four-core CPU running at 1.1 GHz. The system used Ubuntu 12.04 as operating system and the HEPSPEC 2006 (HS06) benchmarking suite was compiled natively with gcc-4.4 on the system. The benchmark was run for various settings of the relevant gcc compiler options. We did not find significant influence from the compiler options on the benchmark result. The final HS06 benchmark result is 10.4.
Transient flows and pressure waves in pipes
Wang, X.Q.; Sun, J.G.; Sha, W.T.
Transient laminar flows and pressure-wave propagations in pipes connected with components, commonly known as water hammer, are analyzed. The system studied consists of a constant-pressure vessel, a uniform circular pipe, a valve between them, and a receiver vessel. A pressure-wave equation and a linearized velocity equation are derived from the equations of mass and momentum conservation. Waveform distortion due to viscous dissipation and pipe-wall elastic expansion is characterized by a dimensionless transmission number, K. The coefficients of the damping of the pressure waves were found to be related to the roots of the Bessel function J{sub 0}. An exact solution of the pressure-wave equation was obtained numerically. The relationship between the distortion of a traveling wave and the transmission number K was studied. The problem is also calculated with a general-purpose computer code, COMMIX, which solves the exact mass conservation equation and Navier-Stokes equations. The COMMIX calculational results agreed well with the analytical solutions.
A REPORT ON INCREASING 'l'HE l'HRUSX OF A :.I:URBOJEl' ENGINE BY COHBUSXION OF FUEL IN IHE XAIL PIPE
Winfree, Erik
PIPE '.L'hel!lis by Lt. Comdr. C.E. Gibson, U.S.N. Lf.. Comdr. E.L. Knapp, U.S.N. U.. Comdr. R. Combustion Problems.~. V. Equipment. � � . . . . VI. Tail Pipe Combustion System.� VII. Experimental Addition. � � 32 3. Theoretical Maximum Thrust Ratio GE I-14B Unit Straight Tail Pipe � � � . Control
Synthetic benchmark for modeling flow in 3D fractured media
NASA Astrophysics Data System (ADS)
de Dreuzy, Jean-Raynald; Pichot, G�raldine; Poirriez, Baptiste; Erhel, Jocelyne
Intensity and localization of flows in fractured media have promoted the development of a large range of different modeling approaches including Discrete Fracture Networks, pipe networks and equivalent continuous media. While benchmarked usually within site studies, we propose an alternative numerical benchmark based on highly-resolved Discrete Fracture Networks (DFNs) and on a stochastic approach. Test cases are built on fractures of different lengths, orientations, aspect ratios and hydraulic apertures, issuing the broad ranges of topological structures and hydraulic properties classically observed. We present 18 DFN cases, with 10 random simulations by case. These 180 DFN structures are provided and fully documented. They display a representative variety of the configurations that challenge the numerical methods at the different stages of discretization, mesh generation and system solving. Using a previously assessed mixed hybrid finite element method (Erhel et al., 2009a), we systematically provide reference flow and head solutions. Because CPU and memory requirements stem mainly from system solving, we study direct and iterative sparse linear solvers. We show that the most cpu-time efficient method is a direct multifrontal method for small systems, while conjugate gradient preconditioned by algebraic multrigrid is more relevant at larger sizes. Available results can be used further as references for building up alternative numerical and physical models in both directions of improving accuracy and efficiency.
Ground truth and benchmarks for performance evaluation
NASA Astrophysics Data System (ADS)
Takeuchi, Ayako; Shneier, Michael; Hong, Tsai Hong; Chang, Tommy; Scrapper, Christopher; Cheok, Geraldine S.
Progress in algorithm development and transfer of results to practical applications such as military robotics requires the setup of standard tasks, of standard qualitative and quantitative measurements for performance evaluation and validation. Although the evaluation and validation of algorithms have been discussed for over a decade, the research community still faces a lack of well-defined and standardized methodology. The range of fundamental problems include a lack of quantifiable measures of performance, a lack of data from state-of-the-art sensors in calibrated real-world environments, and a lack of facilities for conducting realistic experiments. In this research, we propose three methods for creating ground truth databases and benchmarks using multiple sensors. The databases and benchmarks will provide researchers with high quality data from suites of sensors operating in complex environments representing real problems of great relevance to the development of autonomous driving systems. At NIST, we have prototyped a High Mobility Multi-purpose Wheeled Vehicle (HMMWV) system with a suite of sensors including a Riegl ladar, GDRS ladar, stereo CCD, several color cameras, Global Position System (GPS), Inertial Navigation System (INS), pan/tilt encoders, and odometry . All sensors are calibrated with respect to each other in space and time. This allows a database of features and terrain elevation to be built. Ground truth for each sensor can then be extracted from the database. The main goal of this research is to provide ground truth databases for researchers and engineers to evaluate algorithms for effectiveness, efficiency, reliability, and robustness, thus advancing the development of algorithms.
Excitation and scattering of guided waves: relationships between solutions for plates and pipes.
Velichko, Alexander; Wilcox, Paul D
The detection of localized defects such as cracks and corrosion in pipes using guided elastic waves is now an established non-destructive testing procedure. However, the prediction of guided wave excitation and scattering in pipes is a complex three-dimensional (3D) problem with many parameters that can generally only be solved using numerical methods. In many important industrial applications, the diameter of a pipe is much larger than wall thickness. In this case an approximate theory is applicable, when a pipe is considered as an unwrapped isotropic plate. In this paper, a technique for obtaining pipe mode amplitudes in terms of the solution to the forced 3D problem on a plate is presented. The same principle is extended to relate guided wave scattering from defects in plates to scattered circumferential modal amplitudes from defects in pipe. This is of practical benefit as the scattering of guided waves by defects in a plate is a much simpler problem than that in a pipe, and one that, in some cases, can be solved using analytical methods. Results are shown that illustrate the application of the method to reflection from through-thickness circumferential cracks in pipes. PMID:19507944
Influence of gravity on flutter of cantilevered pipes conveying fluid
NASA Astrophysics Data System (ADS)
Rivero, Javier; Perez-Saborid, Miguel
We have considered the dynamics of the nonlinear interaction between a flexible pipe and the conveyed fluid in the presence of gravity. The stability of the system (fllutter and buckling) depends on parameters such as the dimensionless fluid flow rate, the gravity to bending stiffness ratio and the fluid to pipe mass ratio and it has been studied in detail both numerically and experimentally. It has also been found that the stabilizing or destabilizing effects of fluid flow depends crucially on the direction of gravity respect to the undeformed midline of the pipe. We have also computed the post-critical behavior of the system by solving the full nonlinear equations of the problem and analyzed the transfer of energy within the system in the nonlinear regime. We have formulated the problem in terms of the angles of the midline of the pipe instead of its transverse displacements, so that we can deal with large deflections without recurring to the quasi-linear approximations concerning the pipe curvature usually made in the literature. Supported by the Ministerio de Educaci�n, Cultura y Deportes of Spain under grant DPI 2010-20450 C03-02.
RISKIND verification and benchmark comparisons
Biwer, B.M.; Arnish, J.J.; Chen, S.Y.; Kamboj, S.
This report presents verification calculations and benchmark comparisons for RISKIND, a computer code designed to estimate potential radiological consequences and health risks to individuals and the population from exposures associated with the transportation of spent nuclear fuel and other radioactive materials. Spreadsheet calculations were performed to verify the proper operation of the major options and calculational steps in RISKIND. The program is unique in that it combines a variety of well-established models into a comprehensive treatment for assessing risks from the transportation of radioactive materials. Benchmark comparisons with other validated codes that incorporate similar models were also performed. For instance, the external gamma and neutron dose rate curves for a shipping package estimated by RISKIND were compared with those estimated by using the RADTRAN 4 code and NUREG-0170 methodology. Atmospheric dispersion of released material and dose estimates from the GENII and CAP88-PC codes. Verification results have shown the program to be performing its intended function correctly. The benchmark results indicate that the predictions made by RISKIND are within acceptable limits when compared with predictions from similar existing models.
Heat pipes and their technical applications
L. L. Vasilev
A general review paper on heat pipes is presented with attention given to principles of operation. Also considered are transfer processes in heat-pipe wicks, the effect of the structural characteristics of a wick on convective transfer of the working fluid, and heat and mass transfer in the wicks of low-temperature heat pipes. Applications of heat pipes in such fields as
Determination of Secondary Encasement Pipe Design Pressure
This document published results of iterative calculations for maximum tank farm transfer secondary pipe (encasement) pressure upon failure of the primary pipe. The maximum pressure was calculated from a primary pipe guillotine break. Results show encasement pipeline design or testing pressures can be significantly lower than primary pipe pressure criteria.
Code of Federal Regulations, 2012 CFR
...2012-10-01 2012-10-01 false Piping. 108.447 Section 108.447 Shipping...Fire Extinguishing Systems � 108.447 Piping. (a) Each pipe, valve, and fitting...pounds per square inch). (b) All piping for a CO2 system of nominal size...
Huang, Haiying
Page 1 of 1 Track A Pipe School� Presented by: Terry McArthur; PE, CDT Senior Professional Registration 8:15 Overview of Different Pipe Materials � An overview of different pipe materials and their capabilities and limitations for pressure and gravity applications. 9:00 Rigid and Flexible Pipes: A comparison
Structural Assessment of Small Bore Feeder Piping
PIPES AND VALIDATE COMPUTATIONAL METHODS COMPARED TO FULL SCALE TESTS TO FAILURE. THE CLIENT CANDUBACKGROUND Structural Assessment of Small Bore Feeder Piping Kathryn Tang, Janos Mann, Skerdi. Supervisor: A. N. Sinclair CASE ONE CANDU REACTORS HAVE 380+ SMALL BORE FEEDER PIPES. THE PIPES
Performance of a heat pipe solar collector
K. A. R. Ismail; M. M. Abogderah
This paper presents a comparative study between theoretical predictions and experimental results of a flat-plate solar collector with heat pipes. The theoretical model for the heat pipe solar collector is based upon the method by Duffie and Beckman (1980), modified to use heat pipes for energy transport. The methanol filled heat pipes are self-contained devices whose evaporators are inserted under
Pipe-soil shear interaction stiffness in horizontal directional drilling and pipe bursting
Abdul Ghafar Chehab; Ian Moore
During horizontal directional drilling and pipe bursting installations, the shear forces between the pipe and the surrounding soil play a major role in the tensile loads and stresses experienced by the pipe. The magnitudes and variations in the shear forces are controlled by the pipe-soil interaction characteristics. This paper discusses the shear interaction between the pipe and the soil during
Variable conductance heat pipe technology
NASA Technical Reports Server (NTRS)
Marcus, B. D.; Edwards, D. K.; Anderson, W. T.
Research and development programs in variable conductance heat pipe technology were conducted. The treatment has been comprehensive, involving theoretical and/or experimental studies in hydrostatics, hydrodynamics, heat transfer into and out of the pipe, fluid selection, and materials compatibility, in addition to the principal subject of variable conductance control techniques. Efforts were not limited to analytical work and laboratory experimentation, but extended to the development, fabrication and test of spacecraft hardware, culminating in the successful flight of the Ames Heat Pipe Experiment on the OAO-C spacecraft.
Abrasion protection in process piping
Accetta, J. [Abresist Corp., Urbana, IN (United States)
Process piping often is subjected to failure from abrasion or a combination of abrasion and corrosion. Abrasion is a complex phenomenon, with many factors involved to varying degrees. Hard, mineral based alumina ceramic and basalt materials are used to provide protection against abrasion in many piping systems. Successful life extension examples are presented from many different industries. Lined piping components require special attention with regard to operating conditions as well as design and engineering considerations. Economic justification involves direct cost comparisons and avoided costs.
Heat pipe life and processing study
NASA Technical Reports Server (NTRS)
Antoniuk, D.; Luedke, E. E.
The merit of adding water to the reflux charge in chemically and solvent cleaned aluminum/slab wick/ammonia heat pipes was evaluated. The effect of gas in the performance of three heat pipe thermal control systems was found significant in simple heat pipes, less significant in a modified simple heat pipe model with a short wickless pipe section. Use of gas data for the worst and best heat pipes of the matrix in a variable conductance heat pipe model showed a 3 C increase in the source temperature at full on condition after 20 and 246 years, respectively.
SCC, bacteria top items in pipe service failures
J. F. Kiefner; R. J. Eiber
This conclusion of a three-part series updating causes of pipeline failures addresses failures due to stress-corrosion cracking (SCC), mechanical damage, and anaerobic bacterial corrosion. These causes, along with hydrogen effects comprise a shift in pipe service problems evident in failures reported since 1979. This shift was identified in a major study by Battelle Columbus Division laboratories. Several failures involving external
Structural Response of Piping to Internal Gas Detonation
Joseph E. Shepherd
Detonation waves in gas-filled piping or tubing pose special challenges in analysis and prediction of structural response. The challenges arise due the nature of the detonation process and the role of fluid-structure interaction in determining the prop- agation and arrest of fractures. Over the past ten years, our laboratory has been engaged in studying this problem and devel- oping methodologies
Roadmap to Realistic Modeling of Closed Loop Pulsating Heat Pipes
Sameer Khandekar; Manfred Groll
Mathematical modeling of pulsating heat pipes through 'first' principles is a contemporary problem which remains quite elusive. Simplifications and assumptions made in all the modeling approaches developed so far render them unsuitable for engineering design because the abstractions contained therein are detached from the real time transport processes taking place in the device. In this paper, a roadmap to realistic
Benchmark for poroelastic and thermoelastic numerical codes
NASA Astrophysics Data System (ADS)
Rozhko, Alexander Y.
Using the method of complex potentials we present the closed form of analytical solution for the stresses and displacements around an elliptical cavity filled with fluid in the permeable poroelastic medium. The far-field pore pressure is different from the pressure inside cavity. The fluid is allowed to diffuse through the cavity's wall towards surrounding medium. The two-dimensional plane-strain and plane-stress models are considered with steady-state distribution of diffusive pore-fluid pressure. The diffusion of fluid is coupled to the deformation of a medium using a linear theory of poroelasticity. Since in the static case the diffusion of pore fluid is controlled by an ordinary Laplace equation, the problem is reduced to elastic problem with distribution of volume forces (known as seepage forces) along gradients of pore pressure. Due to similarity between poroelasticity and thermoelasticity, the present solution is applicable both to the poroelastic and thermoelastic problems with a steady-state distribution of pore pressure and temperature, respectively. Since it is getting more common to model the deformation coupled to Darcy-flow in geosciences and no clear criteria has been suggested for verification of numerical codes, we discuss the possible application of the analytical solution as the benchmark for testing of poroelastic and thermoelastic numerical codes. To stimulate a wider use of the solution for stresses, displacements and pore-fluid pressure around an elliptical cavity are implemented in MATLAB and can be downloaded from the web.
Heat Pipe Applications in Sorption Refrigerators
L. L. Vasiliev; A. G. Kulakov
\\u000a Some sorption refrigeration machines (sorption technologies) developed in Belarus are presented in this paper with emphasises\\u000a on different heat pipes application: conventional heat pipes, heat pipe panels, loop heat pipes, vapour-dynamic thermosyphons,\\u000a etc. Heat pipes are very flexible systems with regards to the effective thermal control. They can easily be implemented inside\\u000a sorption refrigerators and other types of refrigerators [1].
Intermediate Temperature Water Heat Pipe Tests
NASA Technical Reports Server (NTRS)
Devarakonda, Angirasa; Xiong, Daxi; Beach, Duane E.
Heat pipes are among the most promising technologies for space radiator systems. Water heat pipes are explored in the intermediate temperature range of 400 to above 500 K. The thermodynamic and thermo-physical properties of water are reviewed in this temperature range. Test Data are reported for a copper-water heat pipe. The heat pipe was tested under different orientations. Water heat pipes show promise in this temperature range.Fabrication and testing issues are being addressed.
Intermediate Temperature Water Heat Pipe Tests
NASA Technical Reports Server (NTRS)
Devarakonda, Angirasa; Xiong, Da-Xi; Beach, Duane E.
Heat pipes are among the most promising technologies for space radiator systems. Water heat pipes are explored in the intermediate temperature range of 400 to above 500 K. The thermodynamic and thermo-physical properties of water are reviewed in this temperature range. Test data are reported for a copper-water heat pipe. The heat pipe was tested under different orientations. Water heat pipes show promise in this temperature range. Fabrication and testing issues are being addressed.
Development of high performance sintered powder metal wick cryogenic heat pipes
NASA Astrophysics Data System (ADS)
Compagna, G. L.; Rosenfeld, J. H.
This paper presents recent development efforts at Eastman Kodak and Thermacore in the area of design, analysis, and testing of cryogenic heat pipes. Two nitrogen heat pipes designed to operate near 80K were designed, built and tested. The first heat pipe was 0.96 meters long and used a sintered homogeneous powder wick that demonstrated a heat transport capability of 3.5 watts at approximately 80K. The second heat pipe was 0.95 meters long with a sintered artery wick that demonstrated a capability of 20 to 25 watts at 0.004 m against gravity at 95K. The cryogenic arterial heat pipe represents an advance in heat pipe technology; twenty-fold improvement in performance is possible compared to a sintered homogeneous powder metal wick. The improvement results from use of a boiling-resistant artery design employing sintered wick technology. Also presented are support equipment requirements and special problems associated with the testing of cryogenic heat pipes. Some of the unique aspects of cryogenic heat pipes include initial start-up and priming of the system, control of system heat leaks, and determining optimum fluid charge for the heat pipe.
Material characterizations for Benchmark 1 and Benchmark 2
NASA Astrophysics Data System (ADS)
Stoughton, Thomas B.; Shi, Ming F.; Huang, Gang; Yoon, Jeong Whan
This report summarizes material testing on three metals used in the Numisheet 2014 Benchmark Study, a DP 600 steel sheet, a TRIP 780 steel sheet, and an aluminum alloy 5182-O sheet. The tests include r value, yield stress, and hardening in uniaxial tension at 15 degree increments of the loading axis in the plane of the sheet, r value, yield stress, and hardening in equal biaxial tension, and forming limit curves for all three metals. In addition, cyclic tension-compression tests along the rolling direction are reported for the DP 600 and aluminum alloy.
Agricultural drainage pipe detection using ground penetrating radar: Effects of antenna orientation relative to drainage pipe directional trend
Technology Transfer Automated Retrieval System (TEKTRAN)
Locating buried agricultural drainage pipes is a difficult problem confronting farmers and land improvement contractors, especially in the Midwest U.S., where the removal of excess soil water using subsurface drainage systems is a common farm practice. Enhancing the efficiency of soil water removal ...
Physics of heat pipe rewetting
NASA Technical Reports Server (NTRS)
Chan, S. H.
This is the final report which summarizes the research accomplishments under the project entitled 'Physics of Heat Pipe Rewetting' under NASA Grant No. NAG 9-525, Basic, during the period of April 1, 1991 to January 31, 1994. The objective of the research project was to investigate both analytically and experimentally the rewetting characteristics of the heated, grooved plate. The grooved plate is to simulate the inner surface of the vapor channel in monogroove heat pipes for space station design. In such designs, the inner surface of the vapor channel is threaded with monogrooves. When the heat pipe is thermally overloaded, dryout of the monogroove surface occurs. Such a dryout surface should be promptly rewetted to prevent the failure of the heat pipe operation in the thermal radiator of the space station.
Heat Pipes: An Industrial Application�
Murray, F.
This paper reviews the basics of heat pipe exchangers. Included are how they are constructed, how they operate, where they have application, and various aspects of evaluating a potential application. After discussing the technical aspects of heat...
Adapting the SPEC 2000 Benchmark Suite for Simulation-Based Computer Architecture Research
AJ KleinOsowski; John Flynn; Nancy Meares; David J. Lilja
\\u000a The large input datasets in the SPEC 2000 benchmark suite result in unreasonably long simulation times when using detailed\\u000a execution-driven simulators for evaluating future computer architecture ideas. To address this problem, we have an ongoing\\u000a project to reduce the execution times of the SPEC 2000 benchmarks in a quantitatively defensible way. Upon completion of this\\u000a work1, we will have smaller
Meteoroid Protection Methods for Spacecraft Radiators Using Heat Pipes
NASA Technical Reports Server (NTRS)
Ernst, D. M.
Various aspects of achieving a low mass heat pipe radiator for the nuclear electric propulsion spacecraft were studied. Specific emphasis was placed on a concept applicable to a closed Brayton cycle power sub-system. Three aspects of inter-related problems were examined: (1) the armor for meteoroid protection, (2) emissivity of the radiator surface, and (3) the heat pipe itself. The study revealed several alternatives for the achievement of the stated goal, but a final recommendation for the best design requires further investigation.
Heat Pipe Thermal Conditioning Panel
NASA Technical Reports Server (NTRS)
Saaski, E. W.
The technology involved in designing and fabricating a heat pipe thermal conditioning panel to satisfy a broad range of thermal control system requirements on NASA spacecraft is discussed. The design specifications were developed for a 30 by 30 inch heat pipe panel. The fundamental constraint was a maximum of 15 gradient from source to sink at 300 watts input and a flux density of 2 watts per square inch. The results of the performance tests conducted on the panel are analyzed.
Heat pipe cooled power magnetics
NASA Technical Reports Server (NTRS)
Chester, M. S.
A high frequency, high power, low specific weight (0.57 kg/kW) transformer developed for space use was redesigned with heat pipe cooling allowing both a reduction in weight and a lower internal temperature rise. The specific weight of the heat pipe cooled transformer was reduced to 0.4 kg/kW and the highest winding temperature rise was reduced from 40 C to 20 C in spite of 10 watts additional loss. The design loss/weight tradeoff was 18 W/kg. Additionally, allowing the same 40 C winding temperature rise as in the original design, the KVA rating is increased to 4.2 KVA, demonstrating a specific weight of 0.28 kg/kW with the internal loss increased by 50W. This space environment tested heat pipe cooled design performed as well electrically as the original conventional design, thus demonstrating the advantages of heat pipes integrated into a high power, high voltage magnetic. Another heat pipe cooled magnetic, a 3.7 kW, 20A input filter inductor was designed, developed, built, tested, and described. The heat pipe cooled magnetics are designed to be Earth operated in any orientation.
Heat pipe turbine vane cooling
Langston, L.; Faghri, A. [Connecticut Univ., Storrs, CT (United States). Dept. of Mechanical Engineering
The applicability of using heat pipe principles to cool gas turbine vanes is addressed in this beginning program. This innovative concept involves fitting out the vane interior as a heat pipe and extending the vane into an adjacent heat sink, thus transferring the vane incident heat transfer through the heat pipe to heat sink. This design provides an extremely high heat transfer rate and a uniform temperature along the vane due to the internal change of phase of the heat pipe working fluid. Furthermore, this technology can also eliminate hot spots at the vane leading and trailing edges and increase the vane life by preventing thermal fatigue cracking. There is also the possibility of requiring no bleed air from the compressor, and therefore eliminating engine performance losses resulting from the diversion of compressor discharge air. Significant improvement in gas turbine performance can be achieved by using heat pipe technology in place of conventional air cooled vanes. A detailed numerical analysis of a heat pipe vane will be made and an experimental model will be designed in the first year of this new program.
Composite material heat pipe radiator
NASA Astrophysics Data System (ADS)
Gernert, Nelson J.; Sarraf, David B.; Guenther, Richard J.; Hurlbert/, Kathryn Miller
Organic matrix composite material is recognized for its significant strength to weight ratio when compared to metal and consequently was investigated for reducing the mass of heat pipes for future space missions. The particular heat pipe that was constructed and tested was made from an organic matrix composite material applied to a linear of titanium tubing spun to foil thickness (0.076 mm). The thin liner transitioned to heavier-walled ends which allowed the tubing to be sealed using conventional welding. More specifically, the heat pipe was 1.14 m long, 24 mm in diameter and had a mass of 0.165 kg. Water was the working fluid. The heat pipe was tested in a Thermacore thermal vacuum chamber under hot and cold wall operating conditions. The heat load dissipated ranged from 10 to 60 watts. Heat pipe operating temperatures varied from 278 K to 403 K. After testing, the heat pipe was delivered to NASA JSC where future thermal vacuum chamber tests are planned.
Computational Chemistry Comparison and Benchmark Database
National Institute of Standards and Technology Data Gateway
SRD 101 NIST Computational Chemistry Comparison and Benchmark Database (Web, free access)�� The NIST Computational Chemistry Comparison and Benchmark Database is a collection of experimental and ab initio thermochemical properties for a selected set of molecules. The goals are to provide a benchmark set of molecules for the evaluation of ab initio computational methods and allow the comparison between different ab initio computational methods for the prediction of thermochemical properties.
The Wisconsin Benchmark: Past, Present, and Future
David J. Dewitt
In 1981 as we were completing the implementation of the DIRECT database machine (DEWI79, BORA82), attention turned to evaluating its performance. At that time no standard database benchmark existed. There were only a few application-specific benchmarks. While application-specific benchmarks measure which database system is best for a particular application, it was very difficult to understand them. We were interested in
Benchmarking for Excellence and the Nursing Process
NASA Technical Reports Server (NTRS)
Sleboda, Claire
Nursing is a service profession. The services provided are essential to life and welfare. Therefore, setting the benchmark for high quality care is fundamental. Exploring the definition of a benchmark value will help to determine a best practice approach. A benchmark is the descriptive statement of a desired level of performance against which quality can be judged. It must be sufficiently well understood by managers and personnel in order that it may serve as a standard against which to measure value.
46 CFR 154.356 - Cargo emergency jettisoning piping.
Code of Federal Regulations, 2013 CFR
...emergency jettisoning piping. 154.356 Section...Construction and Equipment Ship Arrangements � 154...emergency jettisoning piping. Emergency jettisoning piping must: (a) Meet... Cargo Containment...
46 CFR 154.356 - Cargo emergency jettisoning piping.
Code of Federal Regulations, 2011 CFR
...emergency jettisoning piping. 154.356 Section...Construction and Equipment Ship Arrangements � 154...emergency jettisoning piping. Emergency jettisoning piping must: (a) Meet... Cargo Containment...
46 CFR 154.356 - Cargo emergency jettisoning piping.
Code of Federal Regulations, 2014 CFR
...emergency jettisoning piping. 154.356 Section...Construction and Equipment Ship Arrangements � 154...emergency jettisoning piping. Emergency jettisoning piping must: (a) Meet... Cargo Containment...
46 CFR 154.356 - Cargo emergency jettisoning piping.
Code of Federal Regulations, 2010 CFR
...emergency jettisoning piping. 154.356 Section...Construction and Equipment Ship Arrangements � 154...emergency jettisoning piping. Emergency jettisoning piping must: (a) Meet... Cargo Containment...
46 CFR 154.356 - Cargo emergency jettisoning piping.
Code of Federal Regulations, 2012 CFR
...emergency jettisoning piping. 154.356 Section...Construction and Equipment Ship Arrangements � 154...emergency jettisoning piping. Emergency jettisoning piping must: (a) Meet... Cargo Containment...
Allowable local thickness of wall-thinned straight pipes in ASME Code Case N-597-2
Jai Hak Park; Kyu In Shin; Chi Yong Park; Sung Ho Lee
The wall-thinning problem has become a hot issue in the assessment of the structural integrity of pipes and pipe items. A criterion is necessary to determine the possibility of continuing use for the wall-thinned pipes detected by non-destructive inspection. The American Society of Mechanical Engineers (ASME) Boiler & Pressure (B&PV) Vessel Section XI, Div. 1, Code Case N-597-2 [Requirements for
Heasler, P.G.; Doctor, S.R. [Pacific Northwest National Lab., Richland, WA (United States)
The piping inspection round robin was conducted in 1981 at the Pacific Northwest National Laboratory (PNNL) to quantify the capability of ultrasonics for inservice inspection and to address some aspects of reliability for this type of nondestructive evaluation (NDE). The round robin measured the crack detection capabilities of seven field inspection teams who employed procedures that met or exceeded the 1977 edition through the 1978 addenda of the American Society of Mechanical Engineers (ASME) Section 11 Code requirements. Three different types of materials were employed in the study (cast stainless steel, clad ferritic, and wrought stainless steel), and two different types of flaws were implanted into the specimens (intergranular stress corrosion cracks (IGSCCs) and thermal fatigue cracks (TFCs)). When considering near-side inspection, far-side inspection, and false call rate, the overall performance was found to be best in clad ferritic, less effective in wrought stainless steel and the worst in cast stainless steel. Depth sizing performance showed little correlation with the true crack depths.
The reflection of guided waves from simple dents in pipes.
Ma, Shuyi; Wu, Zhanjun; Wang, Yishou; Liu, Kehai
Guided elastic waves have been anticipated as a rapid screening technique for pipe inspection. Dents occurring in pipes are a severe problem which may lead to the possibility of pipe failure. A study of the reflection characteristics of guided waves from dents of varying geometrical profile in pipes is investigated through experiments. Dented region is represented by a series of circumferential cross-sections and its geometric parameters are described by axial length and the maximum and minimum outer diameters. Both single and double sided dents are mechanically simulated in hollow aluminum pipes and then experimentally tested by exciting the longitudinal L(0,2) mode. A quantitative parameter, so-called deformation rate relating to the maximum and minimum outer diameters of the dents is defined to evaluate the effect of the extent of the deformation on the reflection. For both types of dents, it is shown that the reflection coefficients of the L(0,2) mode are all approximately a linear function of their respective deformation rates. Mode conversion occurs at the dents and reflections of the F(1,3) mode are identified. The results show that the amplitude of the reflected F(1,3) mode is generally higher when the dent has stronger non-axisymmetric features. PMID:25497001
NEP heat pipe radiators. [Nuclear Electric Propulsion
NASA Technical Reports Server (NTRS)
Ernst, D. M.
This paper covers improvements of heat pipe radiators for the thermionic NEP design. Liquid metal heat pipes are suitable as spacecraft radiator elements because of high thermal conductance, low mass and reliability, but the NEP thermionic system design was too large and difficult to fabricate. The current integral collector-radiator design consisting of several layers of thermionic converters, the annular-tangential collector heat pipe, the radiator heat pipe, and the transition zone designed to minimize the temperature difference between the collector heat pipe and radiator heat pipe are described. Finally, the design of micrometeoroid armor protection and the fabrication of the stainless steel annular heat pipe with a tangential arm are discussed, and it is concluded that the heat rejection system for the thermionic NEP system is well advanced, but the collector-radiator heat pipe transition and the 8 to 10 m radiator heat pipe with two bends require evaluation.
Numisheet2005 Benchmark Analysis on Forming of an Automotive Underbody Cross Member: Benchmark 2
Thaweepat Buranathiti; Jian Cao
This report presents an international cooperation benchmark effort focusing on simulations of a sheet metal stamping process. A forming process of an automotive underbody cross member using steel and aluminum blanks is used as a benchmark. Simulation predictions from each submission are analyzed via comparison with the experimental results. A brief summary of various models submitted for this benchmark study
Johnson, Randy
Problem Set 3 Electrodynamics Due: Jan. 28, 2005 Problem 1: Find the force per unit length on a wire of diameter a set inside a metallic cylinder of inner radius R a when the wire is offset from to determine the potential inside a pipe split lengthwise where half of the cylinder is held at 0V
Magnetic refrigeration apparatus with heat pipes
Barclay, John A. (Los Alamos, NM); Prenger, Jr., F. Coyne (Madison, WI)
A magnetic refrigerator operating in the 4 to 20 K range utilizes heat pipes to transfer heat to and from the magnetic material at the appropriate points during the material's movement. In one embodiment circular disks of magnetic material can be interleaved with the ends of the heat pipes. In another embodiment a mass of magnetic material reciprocatingly moves between the end of the heat pipe of pipes that transmits heat from the object of cooling to the magnetic material and the end of the heat pipe or pipes that transmits heat from the magnetic material to a heat sink.
Research on the ITOC based scheduling system for ship piping production
NASA Astrophysics Data System (ADS)
Li, Rui; Liu, Yu-Jun; Hamada, Kunihiro
Manufacturing of ship piping systems is one of the major production activities in shipbuilding. The schedule of pipe production has an important impact on the master schedule of shipbuilding. In this research, the ITOC concept was introduced to solve the scheduling problems of a piping factory, and an intelligent scheduling system was developed. The system, in which a product model, an operation model, a factory model, and a knowledge database of piping production were integrated, automated the planning process and production scheduling. Details of the above points were discussed. Moreover, an application of the system in a piping factory, which achieved a higher level of performance as measured by tardiness, lead time, and inventory, was demonstrated.
New technique for installing screen wicking into Inconel 718 heat pipe
Giriunas, J.A.; Watson, G.K. (NASA Lewis Research Center, 21000 Brookpark Road, Cleveland, Ohio 44135 (United States)); Tower, L.K. (Sverdrup Technology, Inc., Lewis Research Center Group, 2001 Aerospace Parkway, Brook Park, Ohio 44142 (United States))
The creep behavior of superalloys, including Inconel 718, in the presence of liquid sodium is not yet known. To study this problem, the NASA Lewis Research Center has initiated a program with the Energy Technology Engineering Center (ETEC) of Rockwell International Corporation to fill with sodium and creep-test three small cylindrical heat pipes of Inconel 718 for a period of 1000 hours each. This report documents the design and the construction methods that were used at NASA Lewis to fabricate these heat pipes. Of particular importance in the heat pipe construction was the installation of the screen wicking by using an expandable mandrel and differential thermal expansion. This installation technique differs from anything known to have been reported in the heat pipe literature and may be of interest to other workers in the heat pipe field.
TORT solutions for the 3D radiation transport benchmarks for simple geometries with void region
Yousry Y. Azmy; Franz X. Gallmeier; Dick A. Lillie
We present the solutions for the set of three-dimensional radiation transport Benchmark problems obtained with the TORT transport code using its three optional methods: Theta Weighted (?W), Linear Nodal (LN), and Linear Characteristic (LC). Only the cases with 50% scattering are presented in this paper since the nonscattering cases are bound to suffer severe ray effects. By solving the problems
Laboratory evaluation of the Pipe Explorer{trademark} gamma measurement and deployment capability
Cremer, C.D.; Cramer, E.; Lowry, W.
The DOE is faced with the responsibility of decommissioning and dismantling many of its nuclear process facilities. Much of this will involve piping systems which may or may not be contaminated with radioactive material. It is important to be able to differentiate contaminated from non-contaminated material, since the disposal costs for radioactive waste are significant (on the order of hundreds of dollars per cubic foot). In the case of pipes, this determination may be particularly difficult if the pipes are not easily accessible. As a solution to this problem, SEA is developing an inverting membrane technology, called Pipe Explorer{trademark} which uses commercial gamma spectroscopy systems to characterize the radiation levels inside of pipes. The heart of the system is an air-tight membrane which is initially spooled inside of a canister. The end of the membrane protruding out of the canister is folded over and attached to a basepipe. With this configuration, when the canister becomes pressurized the pressure force on the membrane causes the membrane to be pulled from the spool. This continues until the membrane is completely off the spool. A radiation detector is attached to the end of the membrane and towed into the pipe as the membrane continues to evert. The detector cabling is also towed into the pipe. To retrieve the system from a pipe the process is simply reversed, where the cabling, detector, and membrane are wound back onto the spool. The system can thus be used to move a detector freely back and forth through a pipe to provide high resolution analysis of the location of radioactive contamination in pipes. This unique method can deploy the detector and analyze piping systems with multiple elbows and vertical runs. The membrane also serves to protect the expensive detector from contamination.
Benchmark 1 - Nonlinear strain path forming limit of a reverse draw: Part A: Benchmark description
NASA Astrophysics Data System (ADS)
Benchmark-1 Committee
The objective of this benchmark is to demonstrate the predictability of forming limits under nonlinear strain paths for a draw panel with a non-axisymmetric reversed dome-shape at the center. It is important to recognize that treating strain forming limits as though they were static during the deformation process may not lead to successful predictions of this benchmark, due to the nonlinearity of the strain paths involved in this benchmark. The benchmark tool is designed to enable a two-stage draw/reverse draw continuous forming process. Three typical sheet materials, AA5182-O Aluminum, and DP600 and TRIP780 Steels, are selected for this benchmark study.
46 CFR 182.430 - Engine exhaust pipe installation.
Code of Federal Regulations, 2011 CFR
... � 182.430 Engine exhaust pipe installation. (a) The...come in contact with an exhaust pipe. (b) Exhaust gas must not leak from the piping or any connections...under normal conditions. (d) Pipes used for wet exhaust...
46 CFR 119.430 - Engine exhaust pipe installation.
Code of Federal Regulations, 2011 CFR
... � 119.430 Engine exhaust pipe installation. (a) The...come in contact with an exhaust pipe. (b) Exhaust gas must not leak from the piping or any connections...under normal conditions. (d) Pipes used for wet exhaust...
46 CFR 154.512 - Piping: Thermal isolation.
Code of Federal Regulations, 2011 CFR
...Shipping 5 2011-10-01 2011-10-01 false Piping: Thermal isolation. 154.512 Section 154.512 Shipping ...Cargo and Process Piping Systems � 154.512 Piping: Thermal isolation. Low temperature piping must be thermally...
46 CFR 154.512 - Piping: Thermal isolation.
Code of Federal Regulations, 2014 CFR
...Shipping 5 2014-10-01 2014-10-01 false Piping: Thermal isolation. 154.512 Section 154.512 Shipping ...Cargo and Process Piping Systems � 154.512 Piping: Thermal isolation. Low temperature piping must be thermally...
46 CFR 154.512 - Piping: Thermal isolation.
Code of Federal Regulations, 2012 CFR
...Shipping 5 2012-10-01 2012-10-01 false Piping: Thermal isolation. 154.512 Section 154.512 Shipping ...Cargo and Process Piping Systems � 154.512 Piping: Thermal isolation. Low temperature piping must be thermally...
46 CFR 154.512 - Piping: Thermal isolation.
Code of Federal Regulations, 2013 CFR
...Shipping 5 2013-10-01 2013-10-01 false Piping: Thermal isolation. 154.512 Section 154.512 Shipping ...Cargo and Process Piping Systems � 154.512 Piping: Thermal isolation. Low temperature piping must be thermally...
Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey
INTERIOR VIEW WITH LARGE PIPE CASTING MACHINE CASTING A 48' PIPE. - United States Pipe & Foundry Company Plant, Pipe Casting & Testing Area, 2023 St. Louis Avenue at I-20/59, Bessemer, Jefferson County, AL
Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey
INTERIOR VIEW WITH LARGE PIPE CASTING MACHINE EXTRACTING A 48' PIPE. - United States Pipe & Foundry Company Plant, Pipe Casting & Testing Area, 2023 St. Louis Avenue at I-20/59, Bessemer, Jefferson County, AL
46 CFR 153.292 - Separation of piping systems.
Code of Federal Regulations, 2013 CFR
...false Separation of piping systems. 153.292 Section...DANGEROUS CARGOES SHIPS CARRYING BULK LIQUID...Design and Equipment Piping Systems and Cargo Handling Equipment...292 Separation of piping systems. Cargo piping...
46 CFR 153.292 - Separation of piping systems.
Code of Federal Regulations, 2014 CFR
...false Separation of piping systems. 153.292 Section...DANGEROUS CARGOES SHIPS CARRYING BULK LIQUID...Design and Equipment Piping Systems and Cargo Handling Equipment...292 Separation of piping systems. Cargo piping...
46 CFR 153.292 - Separation of piping systems.
Code of Federal Regulations, 2012 CFR
...false Separation of piping systems. 153.292 Section...DANGEROUS CARGOES SHIPS CARRYING BULK LIQUID...Design and Equipment Piping Systems and Cargo Handling Equipment...292 Separation of piping systems. Cargo piping...
46 CFR 154.548 - Cargo piping: Flow capacity.
Code of Federal Regulations, 2012 CFR
...2012-10-01 2012-10-01 false Cargo piping: Flow capacity. 154.548 Section 154...Construction and Equipment Cargo and Process Piping Systems � 154.548 Cargo piping: Flow capacity. Piping with an excess...
46 CFR 154.548 - Cargo piping: Flow capacity.
Code of Federal Regulations, 2013 CFR
...2013-10-01 2013-10-01 false Cargo piping: Flow capacity. 154.548 Section 154...Construction and Equipment Cargo and Process Piping Systems � 154.548 Cargo piping: Flow capacity. Piping with an excess...
46 CFR 119.720 - Nonmetallic piping materials.
Code of Federal Regulations, 2013 CFR
...2013-10-01 2013-10-01 false Nonmetallic piping materials. 119.720 Section 119.720...THAN 49 PASSENGERS MACHINERY INSTALLATION Piping Systems � 119.720 Nonmetallic piping materials. Nonmetallic piping...
46 CFR 119.720 - Nonmetallic piping materials.
Code of Federal Regulations, 2012 CFR
...2012-10-01 2012-10-01 false Nonmetallic piping materials. 119.720 Section 119.720...THAN 49 PASSENGERS MACHINERY INSTALLATION Piping Systems � 119.720 Nonmetallic piping materials. Nonmetallic piping...
46 CFR 119.720 - Nonmetallic piping materials.
Code of Federal Regulations, 2014 CFR
...2014-10-01 2014-10-01 false Nonmetallic piping materials. 119.720 Section 119.720...THAN 49 PASSENGERS MACHINERY INSTALLATION Piping Systems � 119.720 Nonmetallic piping materials. Nonmetallic piping...
46 CFR 154.548 - Cargo piping: Flow capacity.
Code of Federal Regulations, 2014 CFR
...2014-10-01 2014-10-01 false Cargo piping: Flow capacity. 154.548 Section 154...Construction and Equipment Cargo and Process Piping Systems � 154.548 Cargo piping: Flow capacity. Piping with an excess...
46 CFR 154.512 - Piping: Thermal isolation.
Code of Federal Regulations, 2010 CFR
...Shipping 5 2010-10-01 2010-10-01 false Piping: Thermal isolation. 154.512 Section 154.512 Shipping ...Cargo and Process Piping Systems � 154.512 Piping: Thermal isolation. Low temperature piping must be thermally...
46 CFR 116.970 - Protection against hot piping.
Code of Federal Regulations, 2013 CFR
... 2013-10-01 2013-10-01 false Protection against hot piping. 116.970 Section 116.970 Shipping COAST...ARRANGEMENT Rails and Guards � 116.970 Protection against hot piping. Piping, including valves, pipe fittings and...
46 CFR 116.970 - Protection against hot piping.
Code of Federal Regulations, 2010 CFR
... 2010-10-01 2010-10-01 false Protection against hot piping. 116.970 Section 116.970 Shipping COAST...ARRANGEMENT Rails and Guards � 116.970 Protection against hot piping. Piping, including valves, pipe fittings and...
46 CFR 116.970 - Protection against hot piping.
Code of Federal Regulations, 2014 CFR
... 2014-10-01 2014-10-01 false Protection against hot piping. 116.970 Section 116.970 Shipping COAST...ARRANGEMENT Rails and Guards � 116.970 Protection against hot piping. Piping, including valves, pipe fittings and...
46 CFR 177.970 - Protection against hot piping.
Code of Federal Regulations, 2011 CFR
... 2011-10-01 2011-10-01 false Protection against hot piping. 177.970 Section 177.970 Shipping COAST...ARRANGEMENT Rails and Guards � 177.970 Protection against hot piping. Piping, including valves, pipe fittings and...
46 CFR 177.970 - Protection against hot piping.
Code of Federal Regulations, 2012 CFR
... 2012-10-01 2012-10-01 false Protection against hot piping. 177.970 Section 177.970 Shipping COAST...ARRANGEMENT Rails and Guards � 177.970 Protection against hot piping. Piping, including valves, pipe fittings and...
46 CFR 177.970 - Protection against hot piping.
Code of Federal Regulations, 2010 CFR
... 2010-10-01 2010-10-01 false Protection against hot piping. 177.970 Section 177.970 Shipping COAST...ARRANGEMENT Rails and Guards � 177.970 Protection against hot piping. Piping, including valves, pipe fittings and...
46 CFR 116.970 - Protection against hot piping.
Code of Federal Regulations, 2012 CFR
... 2012-10-01 2012-10-01 false Protection against hot piping. 116.970 Section 116.970 Shipping COAST...ARRANGEMENT Rails and Guards � 116.970 Protection against hot piping. Piping, including valves, pipe fittings and...
46 CFR 116.970 - Protection against hot piping.
Code of Federal Regulations, 2011 CFR
... 2011-10-01 2011-10-01 false Protection against hot piping. 116.970 Section 116.970 Shipping COAST...ARRANGEMENT Rails and Guards � 116.970 Protection against hot piping. Piping, including valves, pipe fittings and...
46 CFR 177.970 - Protection against hot piping.
Code of Federal Regulations, 2014 CFR
... 2014-10-01 2014-10-01 false Protection against hot piping. 177.970 Section 177.970 Shipping COAST...ARRANGEMENT Rails and Guards � 177.970 Protection against hot piping. Piping, including valves, pipe fittings and...
46 CFR 177.970 - Protection against hot piping.
Code of Federal Regulations, 2013 CFR
... 2013-10-01 2013-10-01 false Protection against hot piping. 177.970 Section 177.970 Shipping COAST...ARRANGEMENT Rails and Guards � 177.970 Protection against hot piping. Piping, including valves, pipe fittings and...
Centrally activated pipe snubbing system
Cawley, William E. (Richland, WA)
An electromechanical pipe snubbing system and an electromechanical pipe snubber. In the system, each pipe snubber, in a set of pipe snubbers, has an electromechanical mechanism to lock and unlock the snubber. A sensor, such as a seismometer, measures a quantity related to making a snubber locking or unlocking decision. A control device makes an electrical connection between a power supply and each snubber's electromechanical mechanism to simultaneously lock each snubber when the sensor measurement indicates a snubber locking condition. The control device breaks the connection to simultaneously unlock each snubber when the sensor measurement indicates a snubber unlocking condition. In the snubber, one end of the shaft slides within a bore in one end of a housing. The other end of the shaft is rotatably attached to a pipe; the other end of the housing is rotatively attached to a wall. The snubber's electromechanical mechanism locks the slidable end of the shaft to the housing and unlocks that end from the housing. The electromechanical mechanism permits remote testing and lockup status indication for each snubber.
Introduction to the HPC Challenge Benchmark Suite
Piotr Luszczek; Jack J. Dongarra; David Koester; Rolf Rabenseifner; Bob Lucas; Jeremy Kepner; John McCalpin; David Bailey; Daisuke Takahashi
The HPC Challenge benchmark suite has been released by the DARPA HPCS program to help define the performance boundaries of future Petascale computing systems. HPC Challenge is a suite of tests that examine the performance of HPC architectures using kernels with memory access patterns more challenging than those of the High Performance Linpack (HPL) benchmark used in the Top500 list.
Rodinia: A benchmark suite for heterogeneous computing
Shuai Che; Michael Boyer; Jiayuan Meng; David Tarjan; Jeremy W. Sheaffer; Sang-ha Lee; Kevin Skadron
This paper presents and characterizes Rodinia, a benchmark suite for heterogeneous computing. To help architects study emerging platforms such as GPUs (Graphics Processing Units), Rodinia includes applications and kernels which target multi-core CPU and GPU platforms. The choice of applications is inspired by Berkeley's dwarf taxonomy. Our characterization shows that the Rodinia benchmarks cover a wide range of parallel communication
DARPA February 1992 ATIS benchmark test results
David S. Pallett; Nancy L. Dahlgren; Jonathan G. Fiscus; William M. Fisher; John S. Garofolo; Brett C. Tjaden
This paper documents the third in a series of Benchmark Tests for the DARPA Air Travel Information System (ATIS) common task domain. The first results in this series were reported at the June 1990 Speech and Natural Language Workshop [1], and the second at the February 1991 Speech and Natural Language Workshop [2]. The February 1992 Benchmark Tests include: (1)
Communication Characteristics in the NAS Parallel Benchmarks
Yuan, Xin
Communication Characteristics in the NAS Parallel Benchmarks Ahmad Faraj Xin Yuan Department-- In this paper, we investigate the communication characteris- tics of the Message Passing Interface (MPI) implementation of the NAS parallel benchmarks and study the effectiveness of com- piled communication for MPI
Healthcare: A Lesson in Benchmarking for Educators.
ERIC Educational Resources Information Center
Inger, Morton
Hospitals--the most costly segment of the health care system--are beginning to use benchmarking to discover how other hospitals and businesses have developed cost-cutting and time-saving ways of doing things. Benchmarking is a sophisticated, multifaceted procedure, usually conducted by teams, for identifying and adapting best-in-class practices.�
Best practice benchmarking: a route to competitiveness?
Graham Francis; Matthew Hinton; Jacky Holloway; Ian Humphreys
This paper examines the use of best practice benchmarking as an approach to performance improvement in the airline industry. The case study draws upon phenomenological evidence from the aircraft maintenance section of Britannia Airways. A range of benchmarking issues, which could be applied to different divisions of an airline are highlighted. In particular, inter disciplinary team building, employee involvement, relationships
High-performance benchmarking with Web Polygraph
Alex Rousskov; Duane Wessels
SUMMARY This paper presents the design and implementation of Web Polygraph, a tool for benchmarking HTTP intermediaries. We discuss various challenges involved in simulating Web trac and in developing a portable, high performance tool for generating such trac. Polygraph's simulation models, as well as our experiences with developing and running the benchmark, may be useful for Web proxy developers, performance
Time Series Prediction Competition: The CATS Benchmark
Verleysen, Michel
Time Series Prediction Competition: The CATS Benchmark Amaury Lendasse, Erkki Oja and Olli Simula and the time series have become widely used benchmarks. The goal of these competitions is the prediction of the following values of a given time series (30 to 100 values to predict). Unfortunately, the long
A benchmarking scheme for supply chain collaboration
Togar M. Simatupang; Ramaswami Sridharan
Intense competition forces companies to become involved in supply chain collaboration with their upstream and downstream partners. The key to ensuring that the participating members are progressing on the right track of creating the best-in-class practice is to conduct benchmarking. Benchmarking stimulates collective learning for performance improvement that brings benefits to all participating members. However, previous research has focused mainly
Benchmarking supply chain collaboration : An empirical study
Togar M. Simatupang; Ramaswami Sridharan
Supply chain collaboration enables firms to achieve better performance. It requires close arrangements of collaborative practices among the participating members. Searching for better practices and ideas that lead to superior performance means that the chain members also need to benchmark their current collaborative practices to other collaborative supply chains. Benchmarking enables them to identify the highest standards of excellence in
Ontology matching benchmarks: generation and evaluation
Paris-Sud XI, Universit� de
Ontology matching benchmarks: generation and evaluation Maria Rooiu, C�ssia Trojahn, and J�r�me an ontology with systematically modified versions of itself. However, it has two main drawbacks: it has reproduced Benchmark both with the original seed ontology and with other ontologies. Evaluating different
Performance benchmarking using interactive data envelopment analysis
Thierry Post; Jaap Spronk
This paper presents a procedure for performance benchmarking, that extends the performance measurement technique Data Envelopment Analysis (DEA), to incorporate the interactive decision procedure Interactive Multiple Goal Programming (IMGP). The resulting procedure is called Interactive Data Envelopment Analysis (IDEA). It is a decision support tool that helps decision makers to select performance benchmarks that are both feasible and desirable, and
Benchmark Assessment for Improved Learning. AACC Report
ERIC Educational Resources Information Center
Herman, Joan L.; Osmundson, Ellen; Dietel, Ronald
This report describes the purposes of benchmark assessments and provides recommendations for selecting and using benchmark assessments--addressing validity, alignment, reliability, fairness and bias and accessibility, instructional sensitivity, utility, and reporting issues. We also present recommendations on building capacity to support schools'�
New pipe coating facility provides integral services
Not Available
This paper reports on a new pipe coating plant in Birmingham which applies versatile fusion bonded epoxy coating on line pipe manufactured by American Steel Pipe. L. B. Foster Co. opened a new pipe coating plant in Birmingham, Ala., in early 1992 in partnership with American Steel Pipe. The new facility is rapidly becoming an integral part of American Steel Pipe's already extensive capability, providing exclusive coating service to American Steel Pipe and its customers. The new pipe coating plant applies Fostercoat fusion bond epoxy coating to American's 8 5/8 - to 24-in pipe. The addition of Foster's extensive coating capability allows American Steel Pipe to offer its customers manufacturing and coating capability at a single location. Fusion bonding provides the most efficient means of combating corrosion and ensuring long-lasting in ground service. That capability begins at American Steel Pipe's two manufacturing plants where steel pipe is fabricated in diameters from 8 5/8- through 24-in. OD with a wall thickness capability of 0.750 in. Length capabilities of run up to 100 ft for API steel line pipe and up to 120 ft for piling and other structural applications.
Microbially Mediated Kinetic Sulfur Isotope Fractionation: Reactive Transport Modeling Benchmark
NASA Astrophysics Data System (ADS)
Wanner, C.; Druhan, J. L.; Cheng, Y.; Amos, R. T.; Steefel, C. I.; Ajo Franklin, J. B.
Microbially mediated sulfate reduction is a ubiquitous process in many subsurface systems. Isotopic fractionation is characteristic of this anaerobic process, since sulfate reducing bacteria (SRB) favor the reduction of the lighter sulfate isotopologue (S32O42-) over the heavier isotopologue (S34O42-). Detection of isotopic shifts have been utilized as a proxy for the onset of sulfate reduction in subsurface systems such as oil reservoirs and aquifers undergoing uranium bioremediation. Reactive transport modeling (RTM) of kinetic sulfur isotope fractionation has been applied to field and laboratory studies. These RTM approaches employ different mathematical formulations in the representation of kinetic sulfur isotope fractionation. In order to test the various formulations, we propose a benchmark problem set for the simulation of kinetic sulfur isotope fractionation during microbially mediated sulfate reduction. The benchmark problem set is comprised of four problem levels and is based on a recent laboratory column experimental study of sulfur isotope fractionation. Pertinent processes impacting sulfur isotopic composition such as microbial sulfate reduction and dispersion are included in the problem set. To date, participating RTM codes are: CRUNCHTOPE, TOUGHREACT, MIN3P and THE GEOCHEMIST'S WORKBENCH. Preliminary results from various codes show reasonable agreement for the problem levels simulating sulfur isotope fractionation in 1D.
A Seafloor Benchmark for 3-dimensional Geodesy
NASA Astrophysics Data System (ADS)
Chadwell, C. D.; Webb, S. C.; Nooner, S. L.
We have developed an inexpensive, permanent seafloor benchmark to increase the longevity of seafloor geodetic measurements. The benchmark provides a physical tie to the sea floor lasting for decades (perhaps longer) on which geodetic sensors can be repeatedly placed and removed with millimeter resolution. Global coordinates estimated with seafloor geodetic techniques will remain attached to the benchmark allowing for the interchange of sensors as they fail or become obsolete, or for the sensors to be removed and used elsewhere, all the while maintaining a coherent series of positions referenced to the benchmark. The benchmark has been designed to free fall from the sea surface with transponders attached. The transponder can be recalled via an acoustic command sent from the surface to release from the benchmark and freely float to the sea surface for recovery. The duration of the sensor attachment to the benchmark will last from a few days to a few years depending on the specific needs of the experiment. The recovered sensors are then available to be reused at other locations, or again at the same site in the future. Three pins on the sensor frame mate precisely and unambiguously with three grooves on the benchmark. To reoccupy a benchmark a Remotely Operated Vehicle (ROV) uses its manipulator arm to place the sensor pins into the benchmark grooves. In June 2014 we deployed four benchmarks offshore central Oregon. We used the ROV Jason to successfully demonstrate the removal and replacement of packages onto the benchmark. We will show the benchmark design and its operational capabilities. Presently models of megathrust slip within the Cascadia Subduction Zone (CSZ) are mostly constrained by the sub-aerial GPS vectors from the Plate Boundary Observatory, a part of Earthscope. More long-lived seafloor geodetic measures are needed to better understand the earthquake and tsunami risk associated with a large rupture of the thrust fault within the Cascadia subduction zone. Using a ROV to place and remove sensors on the benchmarks will significantly reduce the number of sensors required by the community to monitor offshore strain in subduction zones.
Application of heat pipes in small, industrial facilities requiring low humidity processes
Raustad, R.A.; Nimmo, B.G. [Florida Solar Energy Center, Cape Canaveral, FL (United States). Advanced Technologies Div.
This paper addresses the impact of high humidity on humidity sensitive Florida industries and presents the results of: (1) two Florida surveys which address the perceived severity of the issue; (2) the selection and monitoring of an industrial factory which had a humidity problem that could be mitigated using a commercial heat pipe; and (3) computer simulation of the performance of the AC system within the modeled building for the cases with and without a heat pipe. The application of dehumidifier heat pipes to a cable manufacturing industrial factory, the before and after impact of the installation on the company product and costs are described. A unique aspect of the heat pipe was the ability to turn it on and off by closing or opening ball valves in the heat pipe circuits. Data from the primary system monitoring points (HVAC power, heat pipe, condensate flow, outdoor and indoor temperature and humidity sensors) was connected to a data logger from which it was then sent over the phone lines to the data storage facility. Daily hard copies were also provided. The simulation models for the HVAC system and building were used to estimate the impact of the heat pipe on the manufacturing costs. Use of the heat pipe significantly enhanced the manufacturing conditions in the factory.
Benchmarking ICRF simulations for ITER
R. V. Budny, L. Berry, R. Bilato, P. Bonoli, M. Brambilla, R.J. Dumont, A. Fukuyama, R. Harvey, E.F. Jaeger, E. Lerche, C.K. Phillips, V. Vdovin, J. Wright, and members of the ITPA-IOS
Abstract Benchmarking of full-wave solvers for ICRF simulations is performed using plasma profiles and equilibria obtained from integrated self-consistent modeling predictions of four ITER plasmas. One is for a high performance baseline (5.3 T, 15 MA) DT H-mode plasma. The others are for half-field, half-current plasmas of interest for the pre-activation phase with bulk plasma ion species being either hydrogen or He4. The predicted profiles are used by seven groups to predict the ICRF electromagnetic fields and heating profiles. Approximate agreement is achieved for the predicted heating power partitions for the DT and He4 cases. Profiles of the heating powers and electromagnetic fields are compared.
Development of gprs-based leak detection system for pipe pushing crossing part of nature gas pipeline
Fujun Liu; Shuai Kong; Zhangwei Ling; Mulin Zheng; Yueqiang Qian
There would be a sealed space, called culvert box, between the nature gas pipeline and the concrete pipe when the nature gas pipeline crossing highways, railways and rivers using the trenchless pipe pushing technology. To deal with the problem of leak detection and monitoring for these culvert boxes, which were located in the field and scattered, a GPRS-based (GPRS: general
Mathematical Model of the Optimum Heat Pipe Heat Exchanger for a Condenser of Vapor-Compression Refrigeration Cycle
P. Yeunyongkul; P. Sakulchangsatjatai; P. Terdto
Problem statement: This study theoretically investigated applying heat pipe as a heat exchanger in the condenser of vapor compression refrigeration system for sustainable well-being. Split- type air conditioner for residential propose was co nsidered. To reduce pressure drop and recover heat from the condensing process of the refrigeration cy cle, this investigation tried to use Closed Loop Oscillating Heat Pipe
Analysis of the performance of heat pipes and phase-change materials with multiple localized heat sources for space applications
Amir Faghri; Won S. Chang; Edward T. Mahefkey
The objective of this report is to examine the performance characteristics of heat pipes and phase-change materials with multiple localized heat sources as well as the fundamental problems related to their specific applications. A numerical analysis is presented for the overall performance of heat pipes with single or multiple heat sources. The analysis includes the heat conduction in the wall
A new benchmark semi-analytical solution for density-driven flow in porous media
NASA Astrophysics Data System (ADS)
Fahs, Marwan; Younes, Anis; Mara, Thierry Alex
A new benchmark semi-analytical solution is proposed for the verification of density-driven flow codes. The problem deals with a synthetic square porous cavity subject to different salt concentrations at its vertical walls. A steady state semi-analytical solution is investigated using the Fourier-Galerkin method. Contrarily to the standard Henry problem, the cavity benchmark allows high truncation orders in the Fourier series and provides semi-analytical solutions for very small diffusion cases. The problem is also investigated numerically to validate the semi-analytical solution. The obtained results represent a set of new test case high quality data that can be effectively used for benchmarking density-driven flow codes.
Heat pipe design handbook, part 1
NASA Technical Reports Server (NTRS)
Skrabek, E. A.
The development and characteristics of heat pipes are examined. The subjects discussed are: (1) principles of operation, (2) heat pipe theory, (3) pressure gradient effects, (4) variable conductance, (5) design procedure, and (6) performance limit evaluation.
NASA Astrophysics Data System (ADS)
Bourguignon, Jean-Loup
The physics of turbulent pipe flow was investigated via the use of two models based on simplified versions of the Navier-Stokes equations. The first model was a streamwise-constant projection of these equations, and was used to study the change in mean flow that occurs during transition to turbulence. The second model was based on the analysis of the turbulent pipe flow resolvent, and provided a radial basis for the modal decomposition of turbulent pipe flow. The two models were tested numerically and validated against experimental and numerical data. Analysis of the streamwise-constant model showed that both non-normal and nonlinear effects are required to capture the blunting of the velocity profile, which occurs during pipe flow transition. The model generated flow fields characterized by the presence of high- and low-speed streaks, whose distribution over the cross-section of the pipe was remarkably similar to the one observed in the velocity field near the trailing edge of the puff structures present in pipe flow transition. A modal decomposition of turbulent pipe flow, in the three spatial directions and in time, was performed, and made possible by the significant reduction in data requirements achieved via the use of compressive sampling and model-based radial basis functions. The application and efficiency of compressive sampling in wall-bounded turbulence was demonstrated. Approximately sparse representations of turbulent pipe flow by propagating waves with model-based radial basis functions, were derived. The basis functions, obtained by singular value decomposition of the resolvent, captured the wall-normal coherence of the flow; and provided a link between the propagating waves and the governing equations, allowing for the identification of the dominant mechanisms sustaining the waves, as a function of their streamwise wavenumber. Analysis of the resolvent showed that the long streamwise waves are amplified mainly via non-normality effects, and are also constrained to be tall in the wall-normal direction, which decreases the influence of viscous dissipation. The short streamwise waves were shown to be localized near the critical-layer (defined as the wall-normal location where the convection velocity of the wave equals the local mean velocity), and thus exhibit amplification with a large contribution from criticality. The work in this thesis allows the reconciliation of the well-known results concerning optimal disturbance amplification due to non-normal effects with recent resolvent analyses, which highlighted the importance of criticality effects.
Dynamics of heat-pipe reactors
NASA Technical Reports Server (NTRS)
Niederauer, G. F.
A split-core heat pipe reactor, fueled with either U(233)C or U(235)C in a tungsten cermet and cooled by 7-Li-W heat pipes, was examined for the effects of the heat pipes on reactor while trying to safely absorb large reactivity inputs through inherent shutdown mechanisms. Limits on ramp reactivity inputs due to fuel melting temperature and heat pipe wall heat flux were mapped for the reactor in both startup and at-power operating modes.
Calculations to Benchmark Probabilistic Fracture Mechanics Computer Codes
Simonen, Fredric A.; Gosselin, Stephen R.; Wilkowski, Gery M.; Rudland, David L.; Xu, H.
This paper describes calculations to estimate component failure frequencies for components using the PRO-LOCA and PRAISE probabilistic fracture mechanics (PFM) computer codes. These calculations focused on the failure mechanism of intergranular stress corrosion cracking for operating conditions that were known to have failed field components. The objective was to benchmark the newly developed PRO-LOCA code against the older PRAISE code that had a much longer history of prior applications. Another objective was to determine the extent to which uncertainties and modeling assumptions may impact calculated probabilities. It was established that advanced modeling capabilities in the PRO-LOCA code simulated parameters that were treated deterministically by the PRAISE code. Excellent agreement of numerical results from the two codes was established once the PRO-LOCA code was applied using selective deterministic treatments. Benchmarking efforts described in a related paper have compared calculated frequencies with those estimated from plant operating experience. Sensitivity calculations have also been performed to address uncertainties associated with residual stresses and applied stresses and temperatures. The capabilities and limitations of the two PFM codes are described along with prior PFM applications to piping integrity issues. Model assumptions are described along with the uncertain nature of inputs and their impacts on calculated probabilities. Also described are calculations with the PRAISE code that have used an alternative crack initiation model based on laboratory data for crack initiation by PWSCC in Alloy-182. Sensitivity calculations with this model address the effects of uncertainties in levels of operating and residual stresses, uncertainties in plant operating conditions, and circumferential variations of stress.
Thermal Performance of High Temperature Titanium-Water Heat Pipes by Multiple Heat Pipe Manufacturers
NASA Technical Reports Server (NTRS)
Sanzi, James L.
Titanium-water heat pipes are being investigated for use in heat rejection systems for lunar and Mars fission surface power systems. Heat pipes provide an efficient and reliable means to transfer heat to a radiator heat rejection system. NASA Glenn Research Center requisitioned nine titanium water heat pipes from three vendors. Each vendor supplied three heat pipes 1.25 cm diameter by 1.1 meter long with each vendor selecting a different wick design. Each of the three heat pipes is slightly different in construction. Additional specifications for the heat pipes included 500 K nominal operating temperature, light weight, and freeze tolerance. The heat pipes were performance tested gravity-aided, in the horizontal position and at elevations against gravity at 450 and 500 K. Performance of the three heat pipes is compared. The heat pipe data will be used to verify models of heat pipe radiators that will be used in future space exploration missions.
Thermal Performance of High Temperature Titanium -- Water Heat Pipes by Multiple Heat Pipe Manufacturers
NASA Technical Reports Server (NTRS)
Sanzi, James L.
Titanium - water heat pipes are being investigated for use in heat rejection systems for lunar and Mars fission surface power systems. Heat pipes provide an efficient and reliable means to transfer heat to a radiator heat rejection system. NASA Glenn Research Center requisitioned nine titanium water heat pipes from three vendors. Each vendor supplied three heat pipes 1.25 cm diameter by 1.1 meter long with each vendor selecting a different wick design. Each of the three heat pipes is slightly different in construction. Additional specifications for the heat pipes included 500 K nominal operating temperature, light weight, and freeze tolerance. The heat pipes were performance tested gravity-aided, in the horizontal position and at elevations against gravity at 450 K and 500 K. Performance of the three heat pipes is compared. The heat pipe data will be used to verify models of heat pipe radiators that will be used in future space exploration missions.
Code of Federal Regulations, 2012 CFR
... 3 2012-10-01 2012-10-01 false Plastic pipe. 192.59 Section 192.59 Transportation...FEDERAL SAFETY STANDARDS Materials � 192.59 Plastic pipe. (a) New plastic pipe is qualified for use under this part...
Code of Federal Regulations, 2013 CFR
... 3 2013-10-01 2013-10-01 false Plastic pipe. 192.59 Section 192.59 Transportation...FEDERAL SAFETY STANDARDS Materials � 192.59 Plastic pipe. (a) New plastic pipe is qualified for use under this part...
Code of Federal Regulations, 2014 CFR
... 3 2014-10-01 2014-10-01 false Plastic pipe. 192.59 Section 192.59 Transportation...FEDERAL SAFETY STANDARDS Materials � 192.59 Plastic pipe. (a) New plastic pipe is qualified for use under this part...
The follow-on study (initiated in June 1980) continued to monitor performance of 1,400 ft of impregnated concrete pipe installed in several Texas cities. The performance of concrete pipe has been compared with that of sulfur-impregnated concrete pipe; hydrofluoric acid (HF)-treat...
Code of Federal Regulations, 2014 CFR
...Transportation 3 2014-10-01 2014-10-01 false Copper pipe. 192.279 Section 192.279 Transportation...of Materials Other Than by Welding � 192.279 Copper pipe. Copper pipe may not be threaded except that copper...
Code of Federal Regulations, 2010 CFR
...Transportation 3 2010-10-01 2010-10-01 false Copper pipe. 192.279 Section 192.279 Transportation...of Materials Other Than by Welding � 192.279 Copper pipe. Copper pipe may not be threaded except that copper...
Code of Federal Regulations, 2011 CFR
...Transportation 3 2011-10-01 2011-10-01 false Copper pipe. 192.279 Section 192.279 Transportation...of Materials Other Than by Welding � 192.279 Copper pipe. Copper pipe may not be threaded except that copper...
Code of Federal Regulations, 2013 CFR
...Transportation 3 2013-10-01 2013-10-01 false Copper pipe. 192.279 Section 192.279 Transportation...of Materials Other Than by Welding � 192.279 Copper pipe. Copper pipe may not be threaded except that copper...
Code of Federal Regulations, 2012 CFR
...Transportation 3 2012-10-01 2012-10-01 false Copper pipe. 192.279 Section 192.279 Transportation...of Materials Other Than by Welding � 192.279 Copper pipe. Copper pipe may not be threaded except that copper...
Heat pipe waste heat recovery boilers
D. A. Littwin; J. McCurley
The use of heat pipes as transport devices in waste heat recovery boilers is examined. Test results show that heat pipes can efficiently extract heat from the hot gas stream and transfer it inside the pressure vessel for the steam generation process. The benefits of incorporating heat pipes into the design of waste heat recovery boilers include a highly compact
Pipe viscometry of foams C. Enzendorfer
Valk�, Peter
Pipe viscometry of foams C. Enzendorfer Institute of Drilling and Production, Mining University This paper describes a method for extracting useful information from small-scale pipe viscometer,and quality was determined in pipes of five diameters. The flow curves showed a marked dependenceon
Code of Federal Regulations, 2014 CFR
...Shipping 3 2014-10-01 2014-10-01 false Piping. 76.25-30 Section 76.25-30 Shipping...Automatic Sprinkling System, Details � 76.25-30 Piping. (a) All piping, valves, and fittings of ferrous materials...
Original article Worker piping associated with foraging
Paris-Sud XI, Universit� de
Original article Worker piping associated with foraging in undisturbed queenright colonies of honey piping, previously reported only in association with colony disturbance or queen- lessness, was seen in undisturbed, queenright colonies. Workers piped by pressing the thorax to the comb, spreading the wings
Code of Federal Regulations, 2012 CFR
...Shipping 3 2012-10-01 2012-10-01 false Piping. 76.25-30 Section 76.25-30 Shipping...Automatic Sprinkling System, Details � 76.25-30 Piping. (a) All piping, valves, and fittings of ferrous materials...
Code of Federal Regulations, 2013 CFR
...Shipping 3 2013-10-01 2013-10-01 false Piping. 76.25-30 Section 76.25-30 Shipping...Automatic Sprinkling System, Details � 76.25-30 Piping. (a) All piping, valves, and fittings of ferrous materials...
Code of Federal Regulations, 2014 CFR
...Requirements � 119.455 Fuel piping. (a) Materials and workmanship...that: (i) Diesel fuel piping of other materials, such...used; (ii) Diesel fuel piping of aluminum is acceptable...mechanical impact and resistant to failure due to thermal shock....
Code of Federal Regulations, 2013 CFR
...Requirements � 119.455 Fuel piping. (a) Materials and workmanship...that: (i) Diesel fuel piping of other materials, such...used; (ii) Diesel fuel piping of aluminum is acceptable...mechanical impact and resistant to failure due to thermal shock....
Code of Federal Regulations, 2012 CFR
...Requirements � 119.455 Fuel piping. (a) Materials and workmanship...that: (i) Diesel fuel piping of other materials, such...used; (ii) Diesel fuel piping of aluminum is acceptable...mechanical impact and resistant to failure due to thermal shock....
Code of Federal Regulations, 2012 CFR
...Requirements � 182.455 Fuel piping. (a) Materials and workmanship...that: (i) Diesel fuel piping of other materials, such...used; (ii) Diesel fuel piping of aluminum is acceptable...mechanical impact and resistant to failure due to thermal shock....
Code of Federal Regulations, 2013 CFR
...Requirements � 182.455 Fuel piping. (a) Materials and workmanship...that: (i) Diesel fuel piping of other materials, such...used; (ii) Diesel fuel piping of aluminum is acceptable...mechanical impact and resistant to failure due to thermal shock....
Code of Federal Regulations, 2010 CFR
...lines, including pipe, tube, and hose...as seamless steel pipe or tubing, which...iii) When used, flexible hose must meet the...Tubing connections and fittings must be of nonferrous...suitable tools. Tube ends must be annealed...lines, including pipe, tube, and...
Technology Transfer Automated Retrieval System (TEKTRAN)
An autonomous pipe detection algorithm using two independent Artificial Neural Networks (ANN) in two dimensional GPR data has been developed. And a pipe orientation estimation method has been discussed. The first neural network, called step-l ANN, was trained with a waveform reflected from a pipe in...
Code of Federal Regulations, 2011 CFR
... 3 2011-10-01 2011-10-01 false Plastic pipe. 192.59 Section 192.59 Transportation...FEDERAL SAFETY STANDARDS Materials � 192.59 Plastic pipe. (a) New plastic pipe is qualified for use under this part...
Code of Federal Regulations, 2010 CFR
... 3 2010-10-01 2010-10-01 false Plastic pipe. 192.59 Section 192.59 Transportation...FEDERAL SAFETY STANDARDS Materials � 192.59 Plastic pipe. (a) New plastic pipe is qualified for use under this part...
Heat pipe tests on Space Shuttle flights
W. Supper; M. Groll
Heap pipes represent light-weight, highly efficient devices for thermal control. For this reason, their utilization is considered in the context of manned space flight missions and future space stations. Extensive ground tests have been conducted in connection with the development of heat pipe designs for space applications. However, the absence of gravity can affect the processes of heat pipe operation,
Heat pipes in space and on earth
S. Ollendorf
The performance of heat pipes used in the thermal control system of spacecraft such as OAO-III and ATS-6 is discussed, and applications of heat pipes to permafrost stabilization on the Alaska Pipeline and to heat recovery systems are described. Particular attention is given to the ATS-6, launched in 1974, which employs 55 heat pipes to carry solar and internal power
Microstructural characterization of pipe bomb fragments
Otto Gregory; Jimmie Oxley; James Smith; Michael Platek; Hamouda Ghonem; Evan Bernier; Markus Downey; Christopher Cumminskey
Recovered pipe bomb fragments, exploded under controlled conditions, have been characterized using scanning electron microscopy, optical microscopy and microhardness. Specifically, this paper examines the microstructural changes in plain carbon-steel fragments collected after the controlled explosion of galvanized, schedule 40, continuously welded, steel pipes filled with various smokeless powders. A number of microstructural changes were observed in the recovered pipe fragments:
A Statistical Benchmark for BosonSampling
Mattia Walschaers; Jack Kuipers; Juan-Diego Urbina; Klaus Mayer; Malte C. Tichy; Klaus Richter; Andreas Buchleitner
Computing the state of a quantum mechanical many-body system composed of indistinguishable particles distributed over a multitude of modes is one of the paradigmatic test cases of computational complexity theory: Beyond well-understood quantum statistical effects, the coherent superposition of many-particle amplitudes rapidly overburdens classical computing devices - essentially by creating extremely complicated interference patterns, which also challenge experimental resolution. With the advent of controlled many-particle interference experiments, optical set-ups that can efficiently probe many-boson wave functions - baptised BosonSamplers - have therefore been proposed as efficient quantum simulators which outperform any classical computing device, and thereby challenge the extended Church-Turing thesis, one of the fundamental dogmas of computer science. However, as in all experimental quantum simulations of truly complex systems, there remains one crucial problem: How to certify that a given experimental measurement record is an unambiguous result of sampling bosons rather than fermions or distinguishable particles, or of uncontrolled noise? In this contribution, we describe a statistical signature of many-body quantum interference, which can be used as an experimental (and classically computable) benchmark for BosonSampling.
Analytical Benchmark Test Set for Criticality Code Verification
Sood, A.; Forster, R.A.; Parson, D.K.
A number of published numerical solutions to analytic eigenvalue (k{sub eff}) and eigenfunction equations are summarized for the purpose of creating a criticality verification benchmark test set. The 75-problem test set allows the user to verify the correctness of a criticality code for infinite medium and simple geometries in one- and two-energy groups, one- and two-media, and both isotropic and linearly anisotropic neutron scattering. A three- and six-energy group infinite medium problem are also included in the test set. The problem specifications will produce both k{sub eff}=1 and the quoted k{sub {infinity}} to at least five decimal places. Additional uses of the test set for code verification are also discussed. Los Alamos report LA-13511 contains the details of all 75 test problems.
An efficient procedure of static analysis of long ocean mining pipe
Tikhonov, V.S.; Fisher, A.S.; Zubarev, V.K.
The paper develops an efficiency numerical algorithm for calculation of static characteristics of a long ocean mining pipe hanging from the ship. The algorithm is based on an asymptotic theory of ordinary differential equations, namely, on Tupchiev's method of solution of singularly perturbed boundary-value problems. The developed algorithm is shown to be fairly universal, providing fast and highly accurate computation. Prospects of asymptotic methods for long ocean pipe motion modeling are noted. Examples are given of a pipe static analysis confirming an efficiency of the developed procedure.
ICSBEP Benchmarks For Nuclear Data Applications
Briggs, J. Blair [Idaho National Engineering and Environmental Laboratory (United States)
The International Criticality Safety Benchmark Evaluation Project (ICSBEP) was initiated in 1992 by the United States Department of Energy. The ICSBEP became an official activity of the Organization for Economic Cooperation and Development (OECD) -- Nuclear Energy Agency (NEA) in 1995. Representatives from the United States, United Kingdom, France, Japan, the Russian Federation, Hungary, Republic of Korea, Slovenia, Serbia and Montenegro (formerly Yugoslavia), Kazakhstan, Spain, Israel, Brazil, Poland, and the Czech Republic are now participating. South Africa, India, China, and Germany are considering participation. The purpose of the ICSBEP is to identify, evaluate, verify, and formally document a comprehensive and internationally peer-reviewed set of criticality safety benchmark data. The work of the ICSBEP is published as an OECD handbook entitled ''International Handbook of Evaluated Criticality Safety Benchmark Experiments.'' The 2004 Edition of the Handbook contains benchmark specifications for 3331 critical or subcritical configurations that are intended for use in validation efforts and for testing basic nuclear data. New to the 2004 Edition of the Handbook is a draft criticality alarm / shielding type benchmark that should be finalized in 2005 along with two other similar benchmarks. The Handbook is being used extensively for nuclear data testing and is expected to be a valuable resource for code and data validation and improvement efforts for decades to come. Specific benchmarks that are useful for testing structural materials such as iron, chromium, nickel, and manganese; beryllium; lead; thorium; and 238U are highlighted.
Developing integrated benchmarks for DOE performance measurement
Barancik, J.I.; Kramer, C.F.; Thode, Jr. H.C.
The objectives of this task were to describe and evaluate selected existing sources of information on occupational safety and health with emphasis on hazard and exposure assessment, abatement, training, reporting, and control identifying for exposure and outcome in preparation for developing DOE performance benchmarks. Existing resources and methodologies were assessed for their potential use as practical performance benchmarks. Strengths and limitations of current data resources were identified. Guidelines were outlined for developing new or improved performance factors, which then could become the basis for selecting performance benchmarks. Data bases for non-DOE comparison populations were identified so that DOE performance could be assessed relative to non-DOE occupational and industrial groups. Systems approaches were described which can be used to link hazards and exposure, event occurrence, and adverse outcome factors, as needed to generate valid, reliable, and predictive performance benchmarks. Data bases were identified which contain information relevant to one or more performance assessment categories . A list of 72 potential performance benchmarks was prepared to illustrate the kinds of information that can be produced through a benchmark development program. Current information resources which may be used to develop potential performance benchmarks are limited. There is need to develop an occupational safety and health information and data system in DOE, which is capable of incorporating demonstrated and documented performance benchmarks prior to, or concurrent with the development of hardware and software. A key to the success of this systems approach is rigorous development and demonstration of performance benchmark equivalents to users of such data before system hardware and software commitments are institutionalized.
Pre-evaluation of fusion shielding benchmark experiment
Hayashi, K.; Handa, H. [Hitachi Engineering Company, Ltd., Ibaraki (Japan); Konno, C. [Japan Atomic Energy Research Inst. Ibaraki (Japan)] [and others
Shielding benchmark experiment is very useful to test the design code and nuclear data for fusion devices. There are many types of benchmark experiments that should be done in fusion shielding problems, but time and budget are limited. Therefore it will be important to select and determine the effective experimental configurations by precalculation before the experiment. The authors did three types of pre-evaluation to determine the experimental assembly configurations of shielding benchmark experiments planned in FNS, JAERI. (1) Void Effect Experiment - The purpose of this experiment is to measure the local increase of dose and nuclear heating behind small void(s) in shield material. Dimension of the voids and its arrangements were decided as follows. Dose and nuclear heating were calculated both for with and without void(s). Minimum size of the void was determined so that the ratio of these two results may be larger than error of the measurement system. (2) Auxiliary Shield Experiment - The purpose of this experiment is to measure shielding properties of B{sub 4}C, Pb, W, and dose around superconducting magnet (SCM). Thickness of B{sub 4}C, Pb, W and their arrangement including multilayer configuration were determined. (3) SCM Nuclear Heating Experiment - The purpose of this experiment is to measure nuclear heating and dose distribution in SCM material. Because it is difficult to use liquid helium as a part of SCM mock up material, material composition of SCM mock up are surveyed to have similar nuclear heating property of real SCM composition.
LAPUR-K BWR stability benchmark
Kern, R.C. [Nuclear Engineering Technology Corp., Rockville, MD (United States); Rohrer, R.J. [Northern States Power Co., Minneapolis, MN (United States); Belblidia, L.A. [Scandpower Inc., Gaithersburg, MD (United States)
This paper documents the stability benchmark of the LAPUR-K code using the measurements taken at the Ringhals Unit 1 plant over four cycles of operation. This benchmark was undertaken to demonstrate the ability of LAPUR-K to calculate the decay ratios for both core-wide and regional mode oscillations. This benchmark contributes significantly to assuring that LAPUR-K can be used to define the exclusion region for the Monticello Plant in response to recent US Nuclear Regulatory Commission notices concerning oscillation observed at Boiling Water Reactor plants. Stability is part of Northern States Power Reload Safety Evaluation of the Monticello Plant.
Ceramic heat pipe heat exchangers
W. A. Ranken
High-temperature strength, resistance to corrosive atmospheres, and moderate cost combine to make ceramic materials an obvious choice for construction of high-temperature thermal energy recuperator systems. Despite these advantages, ceramic recuperators are steadily being replaced by metallic units at considerable sacrifice in maximum air or fuel preheat temperatures and hence in recovery efficiency. By constructing a recuperator from ceramic heat pipes,
Hot Leg Piping Materials Issues
V. Munne
With Naval Reactors (NR) approval of the Naval Reactors Prime Contractor Team (NRPCT) recommendation to develop a gas cooled reactor directly coupled to a Brayton power conversion system as the space nuclear power plant (SNPP) for Project Prometheus (References a and b) the reactor outlet piping was recognized to require a design that utilizes internal insulation (Reference c). The initial
Pipe inspection and repair system
NASA Technical Reports Server (NTRS)
Schempf, Hagen (Inventor); Mutschler, Edward (Inventor); Chemel, Brian (Inventor); Boehmke, Scott (Inventor); Crowley, William (Inventor)
A multi-module pipe inspection and repair device. The device includes a base module, a camera module, a sensor module, an MFL module, a brush module, a patch set/test module, and a marker module. Each of the modules may be interconnected to construct one of an inspection device, a preparation device, a marking device, and a repair device.
Pipe effect in viscous liquids
V. Capano; S. Esposito; G. Salesi
A detailed experimental and theoretical study has been performed about a phenomenon, not previously reported in the literature, occurring in highly viscous liquids: the formation of a definite pipe structure induced by the passage of a heavy body, this structure lasting for quite a long time. A very rich phenomenology (including mechanical, optical and structural effects) associated with the formation of the pipe has been observed in different liquids. Actually, the peculiar dynamical evolution of that structure does not appear as a trivial manifestation of standard relaxation or spurious effects. In particular we have revealed different time scales during the evolution of the pipe and a non-monotonous decreasing of the persistence time with decreasing viscosity (with the appearance of at least two different maxima). A microscopic model consistent with the experimental data, where the pipe behaves as a cylindrical dielectric shell, has been proposed. The general time evolution of the structure has been described in terms of a simple thermodynamical model, predicting several peculiarities effectively observed.
PWR secondary system pipe thinning
Shor, S.W.W.; Osbourne, M.R. (Bechtel Western Power Corp., San Francisco, CA (USA)); Wilzbach, J.H.; Freid, S.H. (Bechtel Power Corp., Los Angeles, CA (USA))
Nuclear power plants have been experiencing significant thinning of pipe walls from wet steam at least since 1962, when a leak occurred in an extraction line at Dresden Unit 2. Many plants have had valves and piping dow-stream of valves damaged by flashing water. However, it was not until Surry Unit 2 experienced a dramatic pipe rupture in December 1986 at the suction of a feedwater pump that thinning in high energy lnes carrying only liquid water attracted widespread attention, although a similar failure had occurred in a pipe on the discharge side of a heater drain pump at Trojan about 20 months earlier.Seven months after the Surry incident the Nuclear Regulatory Commission issued a bulletin (IEB 87-01) requiring utilities to report their programs to identify and control erosion-corrosion. The NRC also sent out a questionnaire to collect information on the secondary water chemistry of PWRS. Analysis of their responses indicates that not only is erosion-corrosion widespread but that there is need for an easy way to understand its causes in a particular plant, evaluate alternative actions for its correction and arrive at practical, cost-effective programs to control it. This paper suggests how to fill that need in ways that will stop or nearly stop the progress of wall thinning and provide convincing evidence that it has been arrested. Specifically, it identifies water chemistry changes as the most cost-effective way to arrest widespread erosion-corrosion.
Modeling of pulsating heat pipes
Richard C. Givler; Mario J. Martinez
This report summarizes the results of a computer model that describes the behavior of pulsating heat pipes (PHP). The purpose of the project was to develop a highly efficient (as compared to the heat transfer capability of solid copper) thermal groundplane (TGP) using silicon carbide (SiC) as the substrate material and water as the working fluid. The objective of this
Fiberscopic Inspection of Pipe Provers
Iva Williams
American Petroleum Institute (API) standards require the calibration of pipe provers once every five years to establish the known volume. If the prover volume changes during this period, then the calibrated volume and the meter factors obtained will no longer be accurate. Consequently, the actual volumes transferred and the volumes reported as transferred for accounting purposes will be different. Internal
Hanging Bridge Algorithm for Pipe-Routing Design in Ship Engine Room
Lu Huibiao; Yu Zhefu; Sun Peiting
Pipe-routing arrangement in ship engine room is a complex plan problem. Traditional AI algorithms can only satisfy a few special rules. Free spaces mode is a special method for informationally-complete produce models using in complex mechanical plans. Free spaces models, can reduce the number of constrains associated with pipe-routing arrangement and simplify the complexity of a design. The current approaches
Bypass line assisted start-up of a loop heat pipe with a flat evaporator
Joon Hong Boo; Eui Guk Jung
Loop heat pipes often experience start-up problems especially under low thermal loads. A bypass line was installed between\\u000a the evaporator and the liquid reservoir to alleviate the difficulties associated with start-up of a loop heat pipe with flat\\u000a evaporator. The evaporator and condenser had dimensions of 40 mm (W) by 50 mm (L). The wall and tube materials were stainless
Development of a curved pipe capability for the NASTRAN finite element program
NASA Technical Reports Server (NTRS)
Jeter, J. W., Jr.
A curved pipe element capability for the NASTRAN structural analysis program is developed using the NASTRAN dummy element feature. A description is given of the theory involved in the subroutines which describe stiffness, mass, thermal and enforced deformation loads, and force and stress recovery for the curved pipe element. Incorporation of these subroutines into NASTRAN is discussed. Test problems are proposed. Instructions on use of the new element capability are provided.
Benchmarking of performance of Mexican states with effective coverage.
Lozano, Rafael; Soliz, Patricia; Gakidou, Emmanuela; Abbott-Klafter, Jesse; Feehan, Dennis M; Vidal, Cecilia; Ortiz, Juan Pablo; Murray, Christopher J L
Benchmarking of the performance of states, provinces, or districts in a decentralised health system is important for fostering of accountability, monitoring of progress, identification of determinants of success and failure, and creation of a culture of evidence. The Mexican Ministry of Health has, since 2001, used a benchmarking approach based on the WHO concept of effective coverage of an intervention, which is defined as the proportion of potential health gain that could be delivered by the health system to that which is actually delivered. Using data collection systems, including state representative examination surveys, vital registration, and hospital discharge registries, we have monitored the delivery of 14 interventions for 2005-06. Overall effective coverage ranges from 54.0% in Chiapas, a poor state, to 65.1% in the Federal District. Effective coverage for maternal and child health interventions is substantially higher than that for interventions that target other health problems. Effective coverage for the lowest wealth quintile is 52% compared with 61% for the highest quintile. Effective coverage is closely related to public-health spending per head across states; this relation is stronger for interventions that are not related to maternal and child health than those for maternal and child health. Considerable variation also exists in effective coverage at similar amounts of spending. We discuss the implications of these issues for the further development of the Mexican health-information system. Benchmarking of performance by measuring effective coverage encourages decision-makers to focus on quality service provision, not only service availability. The effective coverage calculation is an important device for health-system stewardship. In adopting this approach, other countries should select interventions to be measured on the basis of the criteria of affordability, effect on population health, effect on health inequalities, and capacity to measure the effects of the intervention. The national institutions undertaking this benchmarking must have the mandate, skills, resources, and independence to succeed. PMID:17098091
[Benchmarking of performance of Mexican states with effective coverage].
Lozano, Rafael; Soliz, Patricia; Gakidou, Emmanuela; Abbott-Klafter, Jesse; Feehan, Dennis M; Vidal, Cecilia; Ortiz, Juan Pablo; Murray, Christopher J L
Benchmarking of the performance of states, provinces, or districts in a decentralised health system is important for fostering of accountability, monitoring of progress, identification of determinants of success and failure, and creation of a culture of evidence. The Mexican Ministry of Health has, since 2001, used a benchmarking approach based on the World Health Organization (WHO) concept of effective coverage of an intervention, which is defined as the proportion of potential health gain that could be delivered by the health system to that which is actually delivered. Using data collection systems, including state representative examination surveys, vital registration, and hospital discharge registries, we have monitored the delivery of 14 interventions for 2005-06. Overall effective coverage ranges from 54.0% in Chiapas, a poor state, to 65.1% in the Federal District. Effective coverage for maternal and child health interventions is substantially higher than that for interventions that target other health problems. Effective coverage for the lowest wealth quintile is 52% compared with 61% for the highest quintile. Effective coverage is closely related to public-health spending per head across states; this relation is stronger for interventions that are not related to maternal and child health than those for maternal and child health. Considerable variation also exists in effective coverage at similar amounts of spending. We discuss the implications of these issues for the further development of the Mexican health-information system. Benchmarking of performance by measuring effective coverage encourages decision-makers to focus on quality service provision, not only service availability. The effective coverage calculation is an important device for health-system stewardship. In adopting this approach, other countries should select interventions to be measured on the basis of the criteria of affordability, effect on population health, effect on health inequalities, and capacity to measure the effects of the intervention. The national institutions undertaking this benchmarking must have the mandate, skills, resources, and independence to succeed. PMID:17469399
Geological constraints on the eruption of the Jwaneng Centre kimberlite pipe, Botswana
NASA Astrophysics Data System (ADS)
Brown, R. J.; Gernon, T.; Stiefenhofer, J.; Field, M.
Geological mapping has allowed constraints to be placed on the eruption mechanisms involved in the formation of the Late Permian-Early Triassic Jwaneng Centre kimberlite pipe, Botswana. Twelve lithofacies and three lithofacies associations (LFA 1-3) are recognised. LFA 1 comprises massive to bedded volcaniclastic kimberlite and marginal shale breccias and outcrops over 65% of the surface area of the pipe. It is characterised by a lithic population dominated by Transvaal shale clasts. LFA 1 grades into LFA 2, which comprises massive and bedded volcaniclastic kimberlite and volcaniclastic breccias and outcrops over 19% of the surface area of the pipe. The lithic population of LFA 2 is dominated by contorted and fluidal-outlined Karoo-age mudstones and siltstones. LFA 3 comprises a wedge-shaped unit in the north of the pipe and consists of a series of allochthonous megablocks of sedimentary and volcaniclastic strata. The juvenile clast type and matrix mineral assemblages of the volcaniclastic deposits in the Centre Pipe differ from those in many other southern African kimberlite pipes. Various emplacement models for kimberlite pipes are discussed and evaluated in the light of the new geological data. Both a maar-diatreme model and an explosive volatile-driven eruption model could account for much of the geology of the Centre Pipe and distinguishing between the two models based on deposits alone is difficult. There is strong circumstantial evidence for ambient conditions favourable to phreatomagmatism at the time of the eruption, and the influence of external water may explain the differences between the Jwaneng Centre Pipe and the Class 1 kimberlites common across Southern Africa in terms of both the juvenile clasts and of the inter-clast cement. However, low abundances of some types of lithic inclusions derived from major country rock units pose an unresolved problem for a classic maar-diatreme model of pipe formation.
Arterial and grooved cryogenic heat pipes.
NASA Technical Reports Server (NTRS)
Brennan, P.; Trimmer, D.; Sherman, A.; Cygnarowicz, T.
Tests were conducted on two cryogenic heat pipes using nitrogen as the working fluid. Both pipes are 1.27 cm in diameter. The first pipe is 141 cm long and uses longitudinal grooves in the aluminum wall as the wick structure. The second pipe is 91 cm long and has an arterial wick adjacent to the wall. In addition, circumferential screw threads are machined along the entire length of the inside pipe wall. Both heat pipes primed with no difficulty in the horizontal position. Start-up after burn-out was obtained repeatedly. However, more testing is required to determine whether the artery pipe is as reliable as the grooved pipe with respect to priming. Once primed, the artery heat pipe is much less sensitive to elevation than the grooved design and, consequently, offers a significant advantage with respect to ground testing. Heat-transfer characteristics of the two pipes were comparable, with both pipes achieving the initial goal of 1000 watt-cm of heat-transport capability.
SAFE Alkali Metal Heat Pipe Reliability
NASA Astrophysics Data System (ADS)
Reid, Robert S.
Alkali metal heat pipes are among the best understood and tested of components for first generation space fission reactors. A flight reactor will require production of a hundred or more heat pipes with assured reliability over a number of years. To date, alkali metal heat pipes have been built mostly in low budget development environments with little formal quality assurance. Despite this, heat pipe test samples suggest that high reliability can be achieved with the care justified for space flight qualification. Fabrication procedures have been established that, if consistently applied, ensure long-term trouble-free heat pipe operation. Alkali metal heat pipes have been successfully flight tested in micro gravity and also have been shown capable of multi-year operation with no evidence of sensitivity to fast neutron fluence up to 1023 n/cm2. This represents 50 times the fluence of the proposed Safe Affordable Fission Engine (SAFE-100) heat pipe reactor core.
Underground pipe inspection device and method
Germata, Daniel Thomas (Wadsworth, IL)
A method and apparatus for inspecting the walls of an underground pipe from inside the pipe in which an inspection apparatus having a circular planar platform having a plurality of lever arms having one end pivotably attached to one side of the platform, having a pipe inspection device connected to an opposite end, and having a system for pivoting the lever arms is inserted into the underground pipe, with the inspection apparatus oriented with the planar platform disposed perpendicular to the pipe axis. The plurality of lever arms are pivoted toward the inside wall of the pipe, contacting the inside wall with each inspection device as the apparatus is conveyed along a length of the underground pipe.
Benchmarking sets for molecular docking.
Huang, Niu; Shoichet, Brian K; Irwin, John J
Ligand enrichment among top-ranking hits is a key metric of molecular docking. To avoid bias, decoys should resemble ligands physically, so that enrichment is not simply a separation of gross features, yet be chemically distinct from them, so that they are unlikely to be binders. We have assembled a directory of useful decoys (DUD), with 2950 ligands for 40 different targets. Every ligand has 36 decoy molecules that are physically similar but topologically distinct, leading to a database of 98,266 compounds. For most targets, enrichment was at least half a log better with uncorrected databases such as the MDDR than with DUD, evidence of bias in the former. These calculations also allowed 40x40 cross-docking, where the enrichments of each ligand set could be compared for all 40 targets, enabling a specificity metric for the docking screens. DUD is freely available online as a benchmarking set for docking at http://blaster.docking.org/dud/. PMID:17154509
Numisheet2005 Benchmark Analysis on Forming of an Automotive Underbody Cross Member: Benchmark 2
NASA Astrophysics Data System (ADS)
Buranathiti, Thaweepat; Cao, Jian
This report presents an international cooperation benchmark effort focusing on simulations of a sheet metal stamping process. A forming process of an automotive underbody cross member using steel and aluminum blanks is used as a benchmark. Simulation predictions from each submission are analyzed via comparison with the experimental results. A brief summary of various models submitted for this benchmark study is discussed. Prediction accuracy of each parameter of interest is discussed through the evaluation of cumulative errors from each submission.
Benchmark Gamma Spectroscopy Measurements of Uranium Hexafluoride in Aluminmum Pipe with a Sodium Iodide Detector
Jose A March-Leuba; Taner Uckan; John E Gunning; Patrick D Brukiewa; Belle R Upadhyaya; Stephen M Revis
The expected increased demand in fuel for nuclear power plants, combined with the fact that a significant portion of the current supply from the blend down of weapons-source material will soon be coming to an end, has led to the need for new sources of enriched uranium for nuclear fuel. As a result, a number of countries have announced plans,
XWeB: The XML Warehouse Benchmark
NASA Astrophysics Data System (ADS)
Mahboubi, Hadj; Darmont, J�r�me
With the emergence of XML as a standard for representing business data, new decision support applications are being developed. These XML data warehouses aim at supporting On-Line Analytical Processing (OLAP) operations that manipulate irregular XML data. To ensure feasibility of these new tools, important performance issues must be addressed. Performance is customarily assessed with the help of benchmarks. However, decision support benchmarks do not currently support XML features. In this paper, we introduce the XML Warehouse Benchmark (XWeB), which aims at filling this gap. XWeB derives from the relational decision support benchmark TPC-H. It is mainly composed of a test data warehouse that is based on a unified reference model for XML warehouses and that features XML-specific structures, and its associate XQuery decision support workload. XWeB's usage is illustrated by experiments on several XML database management systems.
NASA Astrophysics Data System (ADS)
van der Marck, Steven C.
The new major release VII.0 of the ENDF/B nuclear data library has been tested extensively using benchmark calculations. These were based upon MCNP-4C3 continuous-energy Monte Carlo neutronics simulations, together with nuclear data processed using the code NJOY. Three types of benchmarks were used, viz., criticality safety benchmarks, (fusion) shielding benchmarks, and reference systems for which the effective delayed neutron fraction is reported. For criticality safety, more than 700 benchmarks from the International Handbook of Criticality Safety Benchmark Experiments were used. Benchmarks from all categories were used, ranging from low-enriched uranium, compound fuel, thermal spectrum ones (LEU-COMP-THERM), to mixed uranium-plutonium, metallic fuel, fast spectrum ones (MIX-MET-FAST). For fusion shielding many benchmarks were based on IAEA specifications for the Oktavian experiments (for Al, Co, Cr, Cu, LiF, Mn, Mo, Si, Ti, W, Zr), Fusion Neutronics Source in Japan (for Be, C, N, O, Fe, Pb), and Pulsed Sphere experiments at Lawrence Livermore National Laboratory (for 6Li, 7Li, Be, C, N, O, Mg, Al, Ti, Fe, Pb, D 2O, H 2O, concrete, polyethylene and teflon). For testing delayed neutron data more than thirty measurements in widely varying systems were used. Among these were measurements in the Tank Critical Assembly (TCA in Japan) and IPEN/MB-01 (Brazil), both with a thermal spectrum, and two cores in Masurca (France) and three cores in the Fast Critical Assembly (FCA, Japan), all with fast spectra. In criticality safety, many benchmarks were chosen from the category with a thermal spectrum, low-enriched uranium, compound fuel (LEU-COMP-THERM), because this is typical of most current-day reactors, and because these benchmarks were previously underpredicted by as much as 0.5% by most nuclear data libraries (such as ENDF/B-VI.8, JEFF-3.0). The calculated results presented here show that this underprediction is no longer there for ENDF/B-VII.0. The average over 257 benchmarks deviates only 0.017% from the measured benchmark value. Moreover, no clear trends (with e.g. enrichment, lattice pitch, or spectrum) have been observed. Also for fast spectrum benchmarks, both for intermediately or highly enriched uranium and for plutonium, clear improvements are apparent from the calculations. The results for bare assemblies have improved, as well as those with a depleted or natural uranium reflector. On the other hand, the results for plutonium solutions (PU-SOL-THERM) are still high, on average (over 120 benchmarks) roughly 0.6%. Furthermore there still is a bias for a range of benchmarks based on cores in the Zero Power Reactor (ANL) with sizable amounts of tungsten in them. The results for the fusion shielding benchmarks have not changed significantly, compared to ENDF/B-VI.8, for most materials. The delayed neutron testing shows that the values for both thermal and fast spectrum cases are now well predicted, which is an improvement when compared with ENDF/B-VI.8.
Benchmarking Sustainability: the use of Indicators
Zaferatos, Nicholas C.
Benchmarking Sustainability: the use of Indicators Introduction The concept of sustainable development is both very popular and elusive. The overwhelming appeal of sustainability is situated to build a generally shared perception of sustainable development (Butler, 1998). For many people
Toward Scalable Benchmarks for Mass Storage Systems
NASA Technical Reports Server (NTRS)
Miller, Ethan L.
This paper presents guidelines for the design of a mass storage system benchmark suite, along with preliminary suggestions for programs to be included. The benchmarks will measure both peak and sustained performance of the system as well as predicting both short- and long-term behavior. These benchmarks should be both portable and scalable so they may be used on storage systems from tens of gigabytes to petabytes or more. By developing a standard set of benchmarks that reflect real user workload, we hope to encourage system designers and users to publish performance figures that can be compared with those of other systems. This will allow users to choose the system that best meets their needs and give designers a tool with which they can measure the performance effects of improvements to their systems.
Benchmark testing and independent verification of the VS2DT computer code
McCord, J.T. [Sandia National Labs., Albuquerque, NM (United States). Environmental Risk Assessment and Risk Management Dept.; Goodrich, M.T. [IT Corp., Albuquerque, NM (United States)
The finite difference flow and transport simulator VS2DT was benchmark tested against several other codes which solve the same equations (Richards equation for flow and the Advection-Dispersion equation for transport). The benchmark problems investigated transient two-dimensional flow in a heterogeneous soil profile with a localized water source at the ground surface. The VS2DT code performed as well as or better than all other codes when considering mass balance characteristics and computational speed. It was also rated highly relative to the other codes with regard to ease-of-use. Following the benchmark study, the code was verified against two analytical solutions, one for two-dimensional flow and one for two-dimensional transport. These independent verifications show reasonable agreement with the analytical solutions, and complement the one-dimensional verification problems published in the code`s original documentation.
Benchmarks: The Development of a New Approach to Student Evaluation.
ERIC Educational Resources Information Center
Larter, Sylvia
The Toronto Board of Education Benchmarks are libraries of reference materials that demonstrate student achievement at various levels. Each library contains video benchmarks, print benchmarks, a staff handbook, and summary and introductory documents. This book is about the development and the history of the benchmark program. It has taken over 3�
DIPBench: An independent benchmark for Data-Intensive Integration Processes
Matthias B�hm; Dirk Habich; Wolfgang Lehner; Uwe Wloka
The integration of heterogeneous data sources is one of the main challenges within the area of data engineering. Due to the absence of an independent and universal benchmark for data-intensive integration processes, we propose a scalable benchmark, called DIPBench (Data Intensive Integration Process Benchmark), for evaluating the performance of integration sys- tems. This benchmark could be used for subscription systems,
Raising Quality and Achievement. A College Guide to Benchmarking.
ERIC Educational Resources Information Center
Owen, Jane
This booklet introduces the principles and practices of benchmarking as a way of raising quality and achievement at further education colleges in Britain. Section 1 defines the concept of benchmarking. Section 2 explains what benchmarking is not and the steps that should be taken before benchmarking is initiated. The following aspects and�
A Set of Benchmarks fo Modular Testing of SOCs
Erik Jan Marinissen; Vikram Iyengar; Krishnendu Chakrabarty
Abstract: This paper presents the ITC'02 SOC Test Benchmarks. The purpose of this new benchmark set is to stimulate research into newmethods and tools for modular testing of SOCs and to enable the objective comparison of such methods and tools with respect toeffectiveness and efficiency. The paper defines the benchmark format and naming scheme, and presents the benchmark SOCs. Inaddition,
BCSC Performance Benchmarks: Benchmarks for Abnormal Diagnostic Mammography Interpretations (2009 Data)
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BCSC Screening Performance Benchmarks: Benchmarks for Abnormal Screening Mammography Interpretations (2007 Data)
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BCSC Screening Performance Benchmarks: Benchmarks for Abnormal Screening Mammography Interpretations (2009 Data)
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BCSC Performance Benchmarks: Benchmarks for Abnormal Diagnostic Mammography Interpretations (2009 Data)
Skip to Main Content Home � | � Data � | � Statistics � | � Tools � | � Collaborations � | � Work with Us � | � Publications � | � About � | � Links Benchmarks for Cancers by Indication for Examination for Diagnostic Mammography Examinations from 2004
BCSC Performance Benchmarks: Benchmarks for Abnormal Diagnostic Mammography Interpretations (2007 Data)
Skip to Main Content Home � | � Data � | � Statistics � | � Tools � | � Collaborations � | � Work with Us � | � Publications � | � About � | � Links Benchmarks for Cancers by Indication for Examination for Diagnostic Mammography Examinations from 1996
A framework for benchmarking land models
Luo, Yiqi; Randerson, J.; Abramowitz, G.; Bacour, C.; Blyth, E.; Carvalhais, N.; Ciais, Philippe; Dalmonech, D.; Fisher, J.B.; Fisher, R.; Friedlingstein, P.; Hibbard, Kathleen A.; Hoffman, F. M.; Huntzinger, Deborah; Jones, C.; Koven, C.; Lawrence, David M.; Li, D.J.; Mahecha, M.; Niu, S.L.; Norby, Richard J.; Piao, S.L.; Qi, X.; Peylin, P.; Prentice, I.C.; Riley, William; Reichstein, M.; Schwalm, C.; Wang, Y.; Xia, J. Y.; Zaehle, S.; Zhou, X. H.
Land models, which have been developed by the modeling community in the past few decades to predict future states of ecosystems and climate, have to be critically evaluated for their performance skills of simulating ecosystem responses and feedback to climate change. Benchmarking is an emerging procedure to measure performance of models against a set of defined standards. This paper proposes a benchmarking framework for evaluation of land model performances and, meanwhile, highlights major challenges at this infant stage of benchmark analysis. The framework includes (1) targeted aspects of model performance to be evaluated, (2) a set of benchmarks as defined references to test model performance, (3) metrics to measure and compare performance skills among models so as to identify model strengths and deficiencies, and (4) model improvement. Land models are required to simulate exchange of water, energy, carbon and sometimes other trace gases between the atmosphere and land surface, and should be evaluated for their simulations of biophysical processes, biogeochemical cycles, and vegetation dynamics in response to climate change across broad temporal and spatial scales. Thus, one major challenge is to select and define a limited number of benchmarks to effectively evaluate land model performance. The second challenge is to develop metrics of measuring mismatches between models and benchmarks. The metrics may include (1) a priori thresholds of acceptable model performance and (2) a scoring system to combine data�model mismatches for various processes at different temporal and spatial scales. The benchmark analyses should identify clues of weak model performance to guide future development, thus enabling improved predictions of future states of ecosystems and climate. The near-future research effort should be on development of a set of widely acceptable benchmarks that can be used to objectively, effectively, and reliably evaluate fundamental properties of land models to improve their prediction performance skills.
Postmark: a new file system benchmark
J. Katcher
Existing file system benchmarks are deficient in portraying performance in the ephemeral small-file regime used by Internet software, especially: electronicmail; netnews; and web-based commerce. PostMark is a new benchmark to measure performance for this class of application.In this paper, PostMark test results are presented and analyzed for both UNIX and Windows NT application servers. Network Appliance Filers (file server appliances)
Simple Benchmark Specifications for Space Radiation Protection
NASA Technical Reports Server (NTRS)
Singleterry, Robert C. Jr.; Aghara, Sukesh K.
This report defines space radiation benchmark specifications. This specification starts with simple, monoenergetic, mono-directional particles on slabs and progresses to human models in spacecraft. This report specifies the models and sources needed to what the team performing the benchmark needs to produce in a report. Also included are brief descriptions of how OLTARIS, the NASA Langley website for space radiation analysis, performs its analysis.
Implementation of NAS Parallel Benchmarks in Java
NASA Technical Reports Server (NTRS)
Frumkin, Michael; Schultz, Matthew; Jin, Hao-Qiang; Yan, Jerry
A number of features make Java an attractive but a debatable choice for High Performance Computing (HPC). In order to gauge the applicability of Java to the Computational Fluid Dynamics (CFD) we have implemented NAS Parallel Benchmarks in Java. The performance and scalability of the benchmarks point out the areas where improvement in Java compiler technology and in Java thread implementation would move Java closer to Fortran in the competition for CFD applications.