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Load flow analysis: Base cases, data, diagrams, and results
Portante, E.C.; Kavicky, J.A.; VanKuiken, J.C.; Peerenboom, J.P.
This report describes how an electric utility system is modeled by using load flow techniques to establish a validated power flow case suitable for simulating and evaluating alternative system scenarios. Details of the load flow model are supported by additional technical and descriptive information intended to correlate modeled electrical system parameters with the corresponding physical equipment that makes up the system. Pictures and technical specifications of system equipment from the utility, public, or vendor are provided to support this association for many system components. The report summarizes the load flow model construction, simulation, and validation and describes the general capabilities of an information query system designed to access load flow parameters and other electrical system information.
Transaction Based Power Flow Analysis For Transmission Utilization Allocation
transactions as well as the effect of reactive power on transmission losses and active power flows. Two the electric power industry moves into an era of supply competition and consumer choice, the power system electricity market at the ex ante phase; (ii) MW generations are decided by bilateral contracts and other
Operation-Based Signal-Flow AC Analysis of Switching DCDC Converters in CCM and DCM
Rincon-Mora, Gabriel A.
Operation-Based Signal-Flow AC Analysis of Switching DCŁDC Converters in CCM and DCM Dongwon Kwon (CCM and DCM) and insightful enough to derive directly from the waveforms of the circuit, not from- and discontinuous-conduction modes (CCM and DCM). To this end, for review, Sections II and III of the paper overview
Assessment of HTGR Helium Compressor Analysis Tool Based on Newton-Raphson Numerical Application to Through-flow Analysis
Ji Hwan Kim; Hyeun Min Kim; Hee Cheon NO [Korea Advanced Institute of Science and Technology, 335 Gwahangno - 373-1 Guseong-dong, Yuseong-gu, Daejeon 305-701 (Korea, Republic of)
This study describes the development of a computer program for analyzing the off-design performance of axial flow helium compressors, which is one of the major concerns for the power conversion system of a high temperature gas-cooled reactor (HTGR). The compressor performance has been predicted by the aerodynamic analysis of meridional flow with allowances for losses. The governing equations have been derived from Euler turbomachine equation and the streamline curvature method, and then they have been merged into linearized equations based on the Newton-Raphson numerical method. The effect of viscosity is considered by empirical correlations to introduce entropy rises caused by primary loss sources. Use of the method has been illustrated by applying it to a 20-stage helium compressor of the GTHTR300 plant. As a result, the flow throughout the stages of the compressor has been predicted and the compressor characteristics have been also investigated according to the design specification. The program results show much better stability and good convergence with respect to other through-flow methods, and good agreement with the compressor performance map provided by JAEA. (authors)
Study of vaneless diffuser rotating stall based on two-dimensional inviscid flow analysis
Tsujimoto, Yoshinobu; Yoshida, Yoshiki [Osaka Univ., Toyonaka, Osaka (Japan); Mori, Yasumasa [Mitsubishi Motors Corp., Ohta, Tokyo (Japan)
Rotating stalls in vaneless diffusers are studied from the viewpoint that they are basically two-dimensional inviscid flow instability under the boundary conditions of vanishing velocity disturbance at the diffuser inlet and of vanishing pressure disturbance at the diffuser outlet. The linear analysis in the present report shows that the critical flow angle and the propagation velocity are functions of only the diffuser radius ratio. It is shown that the present analysis can reproduce most of the general characteristics observed in experiments: critical flow angle, propagation velocity, velocity, and pressure disturbance fields. It is shown that the vanishing velocity disturbance at the diffuser inlet is caused by the nature of impellers as a resistance and an inertial resistance, which is generally strong enough to suppress the velocity disturbance at the diffuser inlet. This explains the general experimental observations that vaneless diffuser rotating stalls are not largely affected by the impeller.
Improving Surge Flow Irrigation Efficiency Based on Analysis of Infiltration and Hydrodynamic Effects
Smerdon, Ernest T.; Blair, Allie W.
areas were: a) development of a surge flow infiltration model; b) the effect Or wetted perimeter on infiltration in furrow; c) design, construction, and calibration of a physical model of an irrigation border/furrow; and d) development of a surge flow...
Materials Science and Engineering B 117 (2005) 5361 Finite element analysis-based design of a fluid-flow control nano-valve
Grujicic, Mica
Materials Science and Engineering B 117 (2005) 53Ł61 Finite element analysis-based design A finite element method-based procedure is developed for the design of molecularly functionalized nano of a fluid-flow control nano-valve. The results obtained suggest that the finite element-based procedure
ANUDlSiTM-40 Load Flow Analysis: Base Cases, Data, Diagrams, and Results
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del(ANL-IN-03-032)8Li (59AJ76) (See theDoctoral20ALSNewstt^ \ #ANUDlSiTM-40 Load Flow
Miniaturized flow injection analysis system
Folta, James A. (Livermore, CA)
A chemical analysis technique known as flow injection analysis, wherein small quantities of chemical reagents and sample are intermixed and reacted within a capillary flow system and the reaction products are detected optically, electrochemically, or by other means. A highly miniaturized version of a flow injection analysis system has been fabricated utilizing microfabrication techniques common to the microelectronics industry. The microflow system uses flow capillaries formed by etching microchannels in a silicon or glass wafer followed by bonding to another wafer, commercially available microvalves bonded directly to the microflow channels, and an optical absorption detector cell formed near the capillary outlet, with light being both delivered and collected with fiber optics. The microflow system is designed mainly for analysis of liquids and currently measures 38.times.25.times.3 mm, but can be designed for gas analysis and be substantially smaller in construction.
Automation of radiochemical analysis by applying flow
Sßnchez, David
of detection systems, including scintillation counting, a-spectrometers, proportional counters, mass spectrometry and spectrophotometry. ¬ 2010 Published by Elsevier Ltd. Keywords: Flow-analysis technique; Flow
Fluid Gravity Engineering Rocket motor flow analysis
Anand, Mahesh
Fluid Gravity Engineering Capability ┬Ę Rocket motor flow analysis -Internal (performance) -External (plume / contamination) ┬Ę Effect on landing site (surface alteration) -In-depth flow through porous young scientists/engineers Fluid Gravity Engineering Ltd #12;
Flow Imaging Using MRI: Quantification and Analysis
Jiraraksopakun, Yuttapong
dynamics (CFD) and the conventional optimal flow imaging based on particle image velocimetry (PIV). The results demonstrated the improvement from the quantification using solely the conventional HARP method....
Gradual Variation Analysis for Groundwater Flow
Chen, Li
Groundwater flow in Washington DC greatly influences the surface water quality in urban areas. The current methods of flow estimation, based on Darcy's Law and the groundwater flow equation, can be described by the diffusion equation (the transient flow) and the Laplace equation (the steady-state flow). The Laplace equation is a simplification of the diffusion equation under the condition that the aquifer has a recharging boundary. The practical way of calculation is to use numerical methods to solve these equations. The most popular system is called MODFLOW, which was developed by USGS. MODFLOW is based on the finite-difference method in rectangular Cartesian coordinates. MODFLOW can be viewed as a "quasi 3D" simulation since it only deals with the vertical average (no z-direction derivative). Flow calculations between the 2D horizontal layers use the concept of leakage. In this project, we have established a mathematical model based on gradually varied functions for groundwater data volume reconstruction. T...
Analysis of SPRIHTE LOPA flow excursion tests
Laurinat, J.E.
The SPRIHTE FLOPA flow excursion tests, the results of which are presented here, have been modeled using FLOPA, the assembly thermal-hydraulics limits analysis code for the LOPA. FLOPA calculations show T{sub wall} = T{sub sat} is a reliable precursor to the onset of thermal excursion at prototypic flow rates during the ECS addition phase of the LOPA. A FLOPA model was created based on nominal dimensions for the SPRIHTE rig and an assumption that the rig`s cylinders were concentrically located. This model can determine when T{sub wall} = T{sub sat} if adjustments are made to account for differences between measured and calculated subchannel flow and heat transfer rates. To make these adjustments, a multiplier {beta} was applied to the wall saturation temperature criterion (T{sub wall} = {beta} T{sub sat}, in degrees C) to match measured and calculated powers at which the saturation temperature was first exceeded at the wall. Based on preliminary test results, a multiplier of 0.878 was recommended for use in calculating LOPA limits for the K-15.1 subcycle. This multiplier provides margins of 14% to 19% between the calculated wall saturation temperature limits and the measured powers at the onset of thermal excursion. The effective margins used in the final LOPA limits, which include dimensional and heat transfer model uncertainties and biases due to eccentricities, range from 38% to 41%. It is estimated that use of the wall saturation temperature criterion lowers the K-14.1 subcycle LOPA core power limit, which is based on a Stanton number of 0.0025, from 41% to 37% of the historical full power of 2400 MW. This report describes the SPRIHTE LOPA tests, describes and evaluates the FLOPA Model for the SPRIHTE tests, discusses selection of a limit criterion for the SPRIHTE tests, and evaluates the transition between high and low flow rate criteria. Calculated results and a sample of FLOPA input for the analysis of the SPRIHTE tests are provided.
A study of grout flow pattern analysis
Lee, S. Y. [Savannah River National Lab., Aiken, SC (United States); Hyun, S. [Mercer Univ., Macon, GA (United States)
A new disposal unit, designated as Salt Disposal Unit no. 6 (SDU6), is being designed for support of site accelerated closure goals and salt nuclear waste projections identified in the new Liquid Waste System plan. The unit is cylindrical disposal vault of 380 ft diameter and 43 ft in height, and it has about 30 million gallons of capacity. Primary objective was to develop the computational model and to perform the evaluations for the flow patterns of grout material in SDU6 as function of elevation of grout discharge port, and slurry rheology. A Bingham plastic model was basically used to represent the grout flow behavior. A two-phase modeling approach was taken to achieve the objective. This approach assumes that the air-grout interface determines the shape of the accumulation mound. The results of this study were used to develop the design guidelines for the discharge ports of the Saltstone feed materials in the SDU6 facility. The focusing areas of the modeling study are to estimate the domain size of the grout materials radially spread on the facility floor under the baseline modeling conditions, to perform the sensitivity analysis with respect to the baseline design and operating conditions such as elevation of discharge port, discharge pipe diameter, and grout properties, and to determine the changes in grout density as it is related to grout drop height. An axi-symmetric two-phase modeling method was used for computational efficiency. Based on the nominal design and operating conditions, a transient computational approach was taken to compute flow fields mainly driven by pumping inertia and natural gravity. Detailed solution methodology and analysis results are discussed here.
. Our analysis uses the standard finite element framework from [18,24]. The preconditioner also works well in the context of finite differences, however, as some of the examples in ┬Ż 3 illustrateAN AGGREGATION-BASED DOMAIN DECOMPOSITION PRECONDITIONER FOR GROUNDWATER FLOW E. W. JENKINS ┬Ī, C
Infrastructure Analysis Tools: A Focus on Cash Flow Analysis (Presentation)
Melaina, M.; Penev, M.
NREL has developed and maintains a variety of infrastructure analysis models for the U.S. Department of Energy. Business case analysis has recently been added to this tool set. This presentation focuses on cash flow analysis. Cash flows depend upon infrastructure costs, optimized spatially and temporally, and assumptions about financing and revenue. NREL has incorporated detailed metrics on financing and incentives into the models. Next steps in modeling include continuing to collect feedback on regional/local infrastructure development activities and 'roadmap' dynamics, and incorporating consumer preference assumptions on infrastructure to provide direct feedback between vehicles and station rollout.
Exploring multi-layer flow network of international trade based on flow distances
Shen, Bin; Zheng, Qiuhua
Based on the approach of flow distances, the international trade flow system is studied from the perspective of multi-layer flow network. A model of multi-layer flow network is proposed for modelling and analyzing multiple types of flows in flow systems. Then, flow distances are introduced, and symmetric minimum flow distance is presented. Subsequently, we discuss the establishment of the multi-layer flow networks of international trade from two coupled viewpoints, i.e., the viewpoint of commodity flow and that of money flow. Thus, the multi-layer flow networks of international trade is explored. First, trading "trophic levels" are adopted to depict positions that economies occupied in the flow network. We find that the distributions of trading "trophic levels" have the similar clustering pattern for different types of commodity, and there are some regularities between money flow network and commodity flow network. Second, we find that active and competitive countries trade a wide spectrum of products, while ...
Principles of Secure Information Flow Analysis Geoffrey Smith
Smith, Geoffrey
Principles of Secure Information Flow Analysis Geoffrey Smith School of Computing and Information to explain the #12;2 Geoffrey Smith principles underlying secure information flow analysis and to discuss
A new variable in flow analysis
Q. H. Zhang; L. Huo; W. N. Zhang
We have used a simple spectrum distribution which was derived from a hydrodynamical equation\\cite{Csorgo} to fit the data of the STAR group. It is found that it can fit the $v_2$ of STAR group very well. We have found that $v_2$ is sensitive to both the effective temperature of particles and the expanding velocity. We have suggested a new variable ${\\bf z}$ to be used in the flow analysis. This new variable will measure the correlation of particles momentum components. We have also shown that one of the $x$ or $y$ direction in the reaction plane is the direction which has the largest variance.
Probabilistic Vulnerability Assessment Based on Power Flow and Voltage Distribution
Ma, Jian; Huang, Zhenyu; Wong, Pak C.; Ferryman, Thomas A.
Risk assessment of large scale power systems has been an important problem in power system reliability study. Probabilistic technique provides a powerful tool to solve the task. In this paper, we present the results of a study on probabilistic vulnerability assessment on WECC system. Cumulant based expansion method is applied to obtain the probabilistic distribution function (PDF) and cumulative distribution function (CDF) of power flows on transmission lines and voltage. Overall risk index based on the system vulnerability analysis is calculated using the WECC system. The simulation results based on WECC system is used to demonstrate the effectiveness of the method. The methodology can be applied to the risk analysis on large scale power systems.
Recurrent flow analysis in spatiotemporally chaotic 2-dimensional Kolmogorov flow
Dan Lucas; Rich Kerswell
Motivated by recent success in the dynamical systems approach to transitional flow, we study the efficiency and effectiveness of extracting simple invariant sets (recurrent flows) directly from chaotic/turbulent flows and the potential of these sets for providing predictions of certain statistics of the flow. Two-dimensional Kolmogorov flow (the 2D Navier-Stokes equations with a sinusoidal body force) is studied both over a square [0, 2{\\pi}]2 torus and a rectangular torus extended in the forcing direction. In the former case, an order of magnitude more recurrent flows are found than previously (Chandler & Kerswell 2013) and shown to give improved predictions for the dissipation and energy pdfs of the chaos via periodic orbit theory. Over the extended torus at low forcing amplitudes, some extracted states mimick the statistics of the spatially-localised chaos present surprisingly well recalling the striking finding of Kawahara & Kida (2001) in low-Reynolds-number plane Couette flow. At higher forcing amplitudes, however, success is limited highlighting the increased dimensionality of the chaos and the need for larger data sets. Algorithmic developments to improve the extraction procedure are discussed.
Particle filter based on thermophoretic deposition from natural convection flow
Sasse, A.G.B.M.; Nazaroff, W.W. (Univ. of California, Berkeley, CA (United States)); Gadgil, A.J. (Lawrence Berkeley Lab., CA (United States))
We present an analysis of particle migration in a natural convection flow between parallel plates and within the annulus of concentric tubes. The flow channel is vertically oriented with one surface maintained at a higher temperature than the other. Particle migration is dominated by advection in the vertical direction and thermophoresis in the horizontal direction. From scale analysis it is demonstrated that particles are completely removed from air flowing through the channel if its length exceeds L[sub c] = (b[sup 4]g/24K[nu][sup 2]), where b is the width of the channel, g is the acceleration of gravity, K is a thermophoretic coefficient of order 0.5, and [nu] is the kinematic viscosity of air. Precise predictions of particle removal efficiency as a function of system parameters are obtained by numerical solution of the governing equations. Based on the model results, it appears feasible to develop a practical filter for removing smoke particles from a smoldering cigarette in an ashtray by using natural convection in combination with thermophoresis. 22 refs., 8 figs., 1 tab.
Atrioventricular blood flow simulation based on patient-specific data
Sussman, Mark
Atrioventricular blood flow simulation based on patient-specific data Viorel Mihalef1 , Dimitris blood flow in- side the heart, usable with geometric models of the heart from patient- specific data. The method is geared toward realistic simulation of blood flow, taking into account not only heart wall
12. Message Flow Analysis O.M. Nierstrasz
Nierstrasz, Oscar
12. Message Flow Analysis O.M. Nierstrasz ABSTRACT Message management systems with facilities of message flow from the procedure specifications. Message domains are partitioned into state spaces of message flow. 1. Overview Automatic processing and routing of electronic documents yields some interesting
Network Anomaly Detection: Flow-based or Packet-based Approach?
Nguyen, Huy
One of the most critical tasks for network administrator is to ensure system uptime and availability. For the network security, anomaly detection systems, along with firewalls and intrusion prevention systems are the must-have tools. So far in the field of network anomaly detection, people are working on two different approaches. One is flow-based; usually rely on network elements to make so-called flow information available for analysis. The second approach is packet-based; which directly analyzes the data packet information for the detection of anomalies. This paper describes the main differences between the two approaches through an in-depth analysis. We try to answer the question of when and why an approach is better than the other. The answer is critical for network administrators to make their choices in deploying a defending system, securing the network and ensuring business continuity.
Ionization based multi-directional flow sensor
Chorpening, Benjamin T. (Morgantown, WV); Casleton, Kent H. (Morgantown, WV)
A method, system, and apparatus for conducting real-time monitoring of flow (airflow for example) in a system (a hybrid power generation system for example) is disclosed. The method, system and apparatus measure at least flow direction and velocity with minimal pressure drop and fast response. The apparatus comprises an ion source and a multi-directional collection device proximate the ion source. The ion source is configured to generate charged species (electrons and ions for example). The multi-directional collection source is configured to determine the direction and velocity of the flow in real-time.
CFD analysis of laminar oscillating flows
Booten, C. W. Charles W.); Konecni, S. (Snezana); Smith, B. L. (Barton L.); Martin, R. A. (Richard A.)
This paper describes a numerical simulations of oscillating flow in a constricted duct and compares the results with experimental and theoretical data. The numerical simulations were performed using the computational fluid dynamics (CFD) code CFX4.2. The numerical model simulates an experimental oscillating flow facility that was designed to test the properties and characteristics of oscillating flow in tapered ducts, also known as jet pumps. Jet pumps are useful devices in thermoacoustic machinery because they produce a secondary pressure that can counteract an unwanted effect called streaming, and significantly enhance engine efficiency. The simulations revealed that CFX could accurately model velocity, shear stress and pressure variations in laminar oscillating flow. The numerical results were compared to experimental data and theoretical predictions with varying success. The least accurate numerical results were obtained when laminar flow approached transition to turbulent flow.
Multiphase Flow Analysis in Hydra-TH
Christon, Mark A. [Los Alamos National Laboratory; Bakosi, Jozsef [Los Alamos National Laboratory; Francois, Marianne M. [Los Alamos National Laboratory; Lowrie, Robert B. [Los Alamos National Laboratory; Nourgaliev, Robert [Idaho National Laboratory
This talk presents an overview of the multiphase flow efforts with Hydra-TH. The presentation begins with a definition of the requirements and design principles for multiphase flow relevant to CASL-centric problems. A brief survey of existing codes and their solution algorithms is presented before turning the model formulation selected for Hydra-TH. The issues of hyperbolicity and wellposedness are outlined, and a three candidate solution algorithms are discussed. The development status of Hydra-TH for multiphase flow is then presented with a brief summary and discussion of future directions for this work.
CONTINUOUS┬ŁTIME FINITE ELEMENT ANALYSIS OF MULTIPHASE FLOW IN GROUNDWATER HYDROLOGY Zhangxin Chen┬Łwater system in groundwater hydrology is given. The system is written in a fractional flow formulation, i for an air┬Łwater system in groundwater hydrology, ff = a; w [1], [11], [26]: @(OEae ff s ff ) @t +r \\Delta
The Development of Loss of Flow Analysis Method for OPR1000 Using RETRAN
Dong Hyuk Lee; Yo-Han Kim; Chang-Kyung Sung [Korea Electric Power Research Institute, 103-16 Munji-Dong, Yuseong-Gu, Daejeon, 305-380 (Korea, Republic of)
A new loss of flow transient analysis method for OPR1000 (Optimized Power Reactor 1000, previously called KSNP: Korean Standard Nuclear Power Plant) based on RETRAN code were developed. The reference plant for the analysis is Ulchin Unit 3 and the transient analyzed is 4 pump coast-down. The current analysis for loss of RCS flow transient of OPR1000 uses COAST and CESEC codes. The new method uses RETRAN code to replace COAST and CESEC codes. Since the ability of RETRAN to replace CESEC has been studied in other non-LOCA transients, this paper will focus on COAST code and RCP coast-down flow rates. The results from simplified RETRAN nodalization corresponding to COAST show good agreement with RCS flow results from COAST code. The results are also compared with RETRAN base-deck for safety analysis which is more complex and show similar trends. Therefore, previous analysis method for loss of flow of OPR1000 using COAST code can be replaced with the new analysis method based on RETRAN. (authors)
Mechanical analysis of a cross flow filter
Alvin, M.A.; Lippert, T.E.; Attaar, M.H.; McNerney, K.R.
Material properties have also been generated at the Argonne National Laboratories which detail the fracture toughness, Weibull modulus, and critical flaw size for a specifically fabricated lot of P-100A alumina/mullite cross flow filters.(Singh, 1990) The critical flaw size within the P-100A matrix was estimated to be {approximately}500 {mu},m which includes both large interconnected pores, as well as potentially debonded areas along the mid-rib or gas channel seams. Critical flaws are generally considered as potential failure initiation sites within the ceramic matrix. In addition maximum filter element stress levels induced by the process system have been estimated at ANL through the use of finite element computer analyses. These efforts project that the highest stresses result within the flange region of the cross flow filter. As a result of these projections, efforts at Coors Ceramics were directed to improving the overall strength of the alumina/mullite material which is used for cross flow filter fabrication. The results of the efforts at Coors Ceramics provide a significant improvement in the hot strength of the P-100A alumina/mullite filter matrix. Westinghouse assessed the existing nondestructive evaluation (NDE) techniques in terms of identifying methods for detecting critical flaws within the cross flow filter body. To date viable, cost effective methods for detecting critical flaws within the P-100A alumina/mullite matrix, or along the mid-rib bonds or gas channel seams in the full-scale, porous ceramic cross flow filter element are not readily available. As an alternate approach, Westinghouse focused its attention on developing NDE techniques as inspection methods for evaluating the extent of bonding along the mid-rib bonds and gas channel seams which results during the various fabrication stages of the cross flow filter element.
Mechanical analysis of a cross flow filter
Alvin, M.A.; Lippert, T.E.; Attaar, M.H.; McNerney, K.R.
Material properties have also been generated at the Argonne National Laboratories which detail the fracture toughness, Weibull modulus, and critical flaw size for a specifically fabricated lot of P-100A alumina/mullite cross flow filters.(Singh, 1990) The critical flaw size within the P-100A matrix was estimated to be [approximately]500 [mu],m which includes both large interconnected pores, as well as potentially debonded areas along the mid-rib or gas channel seams. Critical flaws are generally considered as potential failure initiation sites within the ceramic matrix. In addition maximum filter element stress levels induced by the process system have been estimated at ANL through the use of finite element computer analyses. These efforts project that the highest stresses result within the flange region of the cross flow filter. As a result of these projections, efforts at Coors Ceramics were directed to improving the overall strength of the alumina/mullite material which is used for cross flow filter fabrication. The results of the efforts at Coors Ceramics provide a significant improvement in the hot strength of the P-100A alumina/mullite filter matrix. Westinghouse assessed the existing nondestructive evaluation (NDE) techniques in terms of identifying methods for detecting critical flaws within the cross flow filter body. To date viable, cost effective methods for detecting critical flaws within the P-100A alumina/mullite matrix, or along the mid-rib bonds or gas channel seams in the full-scale, porous ceramic cross flow filter element are not readily available. As an alternate approach, Westinghouse focused its attention on developing NDE techniques as inspection methods for evaluating the extent of bonding along the mid-rib bonds and gas channel seams which results during the various fabrication stages of the cross flow filter element.
Analysis of oscillating flow cooled SMA actuator
Pachalla Seshadri, Rajagopal
for this heat transfer enhancement is that the oscillatory flow creates a very thin Stokes viscous boundary-layer and hence a large time-dependent transverse temperature gradient at the heated wall. Therefore heat transfer takes place at a large temperature...
Sensitivity Analysis and Stochastic Simulations of Non-equilibrium Plasma Flow
Lin, Guang; Karniadakis, George E.
We study parametric uncertainties involved in plasma flows and apply stochastic sensitivity analysis to rank the importance of all inputs to guide large-scale stochastic simulations. Specifically, we employ different gradient-based sensitivity methods, namely Morris, multi-element probabilistic collocation method (ME-PCM) on sparse grids, Quasi-Monte Carlo, and Monte Carlo methods. These approaches go beyond the standard ``One-At-a-Time" sensitivity analysis and provide a measure of the nonlinear interaction effects for the uncertain inputs. The objective is to perform systematic stochastic simulations of plasma flows treating only as {\\em stochastic processes} the inputs with the highest sensitivity index, hence reducing substantially the computational cost. Two plasma flow examples are presented to demonstrate the capability and efficiency of the stochastic sensitivity analysis. The first one is a two-fluid model in a shock tube while the second one is a one-fluid/two-temperature model in flow past a cylinder.
Validation Analysis of the Shoal Groundwater Flow and Transport Model
A. Hassan; J. Chapman
Environmental restoration at the Shoal underground nuclear test is following a process prescribed by a Federal Facility Agreement and Consent Order (FFACO) between the U.S. Department of Energy, the U.S. Department of Defense, and the State of Nevada. Characterization of the site included two stages of well drilling and testing in 1996 and 1999, and development and revision of numerical models of groundwater flow and radionuclide transport. Agreement on a contaminant boundary for the site and a corrective action plan was reached in 2006. Later that same year, three wells were installed for the purposes of model validation and site monitoring. The FFACO prescribes a five-year proof-of-concept period for demonstrating that the site groundwater model is capable of producing meaningful results with an acceptable level of uncertainty. The corrective action plan specifies a rigorous seven step validation process. The accepted groundwater model is evaluated using that process in light of the newly acquired data. The conceptual model of ground water flow for the Project Shoal Area considers groundwater flow through the fractured granite aquifer comprising the Sand Springs Range. Water enters the system by the infiltration of precipitation directly on the surface of the mountain range. Groundwater leaves the granite aquifer by flowing into alluvial deposits in the adjacent basins of Fourmile Flat and Fairview Valley. A groundwater divide is interpreted as coinciding with the western portion of the Sand Springs Range, west of the underground nuclear test, preventing flow from the test into Fourmile Flat. A very low conductivity shear zone east of the nuclear test roughly parallels the divide. The presence of these lateral boundaries, coupled with a regional discharge area to the northeast, is interpreted in the model as causing groundwater from the site to flow in a northeastward direction into Fairview Valley. Steady-state flow conditions are assumed given the absence of groundwater withdrawal activities in the area. The conceptual and numerical models were developed based upon regional hydrogeologic investigations conducted in the 1960s, site characterization investigations (including ten wells and various geophysical and geologic studies) at Shoal itself prior to and immediately after the test, and two site characterization campaigns in the 1990s for environmental restoration purposes (including eight wells and a year-long tracer test). The new wells are denoted MV-1, MV-2, and MV-3, and are located to the northnortheast of the nuclear test. The groundwater model was generally lacking data in the north-northeastern area; only HC-1 and the abandoned PM-2 wells existed in this area. The wells provide data on fracture orientation and frequency, water levels, hydraulic conductivity, and water chemistry for comparison with the groundwater model. A total of 12 real-number validation targets were available for the validation analysis, including five values of hydraulic head, three hydraulic conductivity measurements, three hydraulic gradient values, and one angle value for the lateral gradient in radians. In addition, the fracture dip and orientation data provide comparisons to the distributions used in the model and radiochemistry is available for comparison to model output. Goodness-of-fit analysis indicates that some of the model realizations correspond well with the newly acquired conductivity, head, and gradient data, while others do not. Other tests indicated that additional model realizations may be needed to test if the model input distributions need refinement to improve model performance. This approach (generating additional realizations) was not followed because it was realized that there was a temporal component to the data disconnect: the new head measurements are on the high side of the model distributions, but the heads at the original calibration locations themselves have also increased over time. This indicates that the steady-state assumption of the groundwater model is in error. To test the robustness of the model d
RESEARCH ARTICLE An optical flow MTV based technique for measuring microfluidic
Garbe, Christoph S.
RESEARCH ARTICLE An optical flow MTV based technique for measuring microfluidic flow for accurately measuring flow fields in microfluidic flows from molecular tagging velocimetry (MTV). Limited optical access is frequently encountered in microfluidic systems. Therefore, in this contribution we
Control Flow Analysis for Reverse Engineering of Sequence Diagrams
Rountev, Atanas "Nasko"
Control Flow Analysis for Reverse Engineering of Sequence Diagrams Atanas Rountev Olga Volgin and in software main- tenance. In static analysis for such reverse engineering, an open question is how to map an iteration. As pointed out in one popular book on modern software development [13], in this context
Characterization of Limiting Factors in Laminar Flow-Based Membraneless Microfuel Cells
Kenis, Paul J. A.
are underway to develop and optimize microscale fuel cells as high-energy-density power source alternatives, where fuel and oxidant are oxidized and re- duced, respectively, is essential for fuel cell optimization reports the analysis of a microflu- idic fuel cell based on laminar flow using an external reference
Experimental investigation and CFD analysis on cross flow in the core of PMR200
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Lee, Jeong-Hun; Yoon, Su-Jong; Cho, Hyoung-Kyu; Jae, Moosung; Park, Goon-Cherl
The Prismatic Modular Reactor (PMR) is one of the major Very High Temperature Reactor (VHTR) concepts, which consists of hexagonal prismatic fuel blocks and reflector blocks made of nuclear gradegraphite. However, the shape of the graphite blocks could be easily changed by neutron damage duringthe reactor operation and the shape change can create gaps between the blocks inducing the bypass flow.In the VHTR core, two types of gaps, a vertical gap and a horizontal gap which are called bypass gap and cross gap, respectively, can be formed. The cross gap complicates the flow field in the reactor core by connectingmoreĀ╗the coolant channel to the bypass gap and it could lead to a loss of effective coolant flow in the fuel blocks. Thus, a cross flow experimental facility was constructed to investigate the cross flow phenomena in the core of the VHTR and a series of experiments were carried out under varying flow rates and gap sizes. The results of the experiments were compared with CFD (Computational Fluid Dynamics) analysis results in order to verify its prediction capability for the cross flow phenomena. Fairly good agreement was seen between experimental results and CFD predictions and the local characteristics of the cross flow was discussed in detail. Based on the calculation results, pressure loss coefficient across the cross gap was evaluated, which is necessary for the thermo-fluid analysis of the VHTR core using a lumped parameter code.½Āless
Modal Wavelets Analysis to Gas-Liquid Two Phase Flow PIV Images
Masahiro Takei [Nihon University, 1866 Kameino, Fujisawa-Shi, Kanagawa 252-8510 (Japan); Hassan, Yassin A. [Texas A and M University, College Station, Texas 77843 (United States); Ortiz-Villafuerte, J. [National Institute for Nuclear Research, Carretera Mexico Toluca Km.36.5, 52045 Municipio de Ocoyoacac, Salazar. Edo. de Mexico, C.P.52046 Mexico (Mexico); Tomomasa Uemura [Kansai University, Suita-shi, Osaka 564 (Japan)
A modal wavelet transform, which overcomes the intrinsic data number limitation of power of two to conventional wavelet transform, has been applied to analysis of pseudo and real bubbly flow PIV images. The modal wavelet transform is compared with the discrete wavelet transform in order to select the best base function among Neumann, Dirichlet and Green function types base functions. Consequently, it is verified that Neumann type base function is the best because the correlation of Neumann type base function is the highest. From the result of wavelet analysis of the real bubbly flow PIV image, as the relative velocity is higher, the dominant eddy scale becomes smaller. The extraction modal wavelet level depends on the base function. (authors)
Flow-Based Detection of Bar Coded Particles
Rose, K A; Dougherty, G M; Santiago, J G
We have developed methods for flow control, electric field alignment, and readout of colloidal Nanobarcodes{copyright}. Our flow-based detection scheme leverages microfluidics and alternate current (AC) electric fields to align and image particles in a well-defined image plane. Using analytical models of the particle rotation in electric fields we can optimize the field strength and frequency necessary to align the particles. This detection platform alleviates loss of information in solution-based assays due to particle clumping during detection.
Geographically Based Hydrogen Demand and Infrastructure Analysis...
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Analysis Geographically Based Hydrogen Demand and Infrastructure Analysis Presentation by NREL's Margo Melendez at the 2010 - 2025 Scenario Analysis for Hydrogen Fuel Cell Vehicles...
Optimal Power Flow Based Demand Response Offer Price Optimization
Lavaei, Javad
Optimal Power Flow Based Demand Response Offer Price Optimization Zhen Qiu 1 Introduction-time energy balance. Demand response programs are offered by the utility companies to reduce the load response cost in exchange for load reduction. A considerable amount of papers have discussed the demand
Platte River Basin Flow Information Web-based Resources
Nebraska-Lincoln, University of
Platte River Basin Flow Information Web-based Resources Gary Stone, Extension Educator, University://www.wrds.uwyo.edu/wrds/nrcs/snowprec/snowprec.html - the University of Wyoming Water Resources Data System - scroll down to the Upper and Lower North Platte River. Seminoe is the first reservoir on the North Platte River in central Wyoming. Glendo is the second
Flow-based XOR Network Coding for Lossy Wireless Networks
Wu, Jie
1 Flow-based XOR Network Coding for Lossy Wireless Networks Abdallah Khreishah, Issa M. Khalil, Pouya Ostovari, and Jie Wu Abstract--A practical way for maximizing the throughput of a wireless network. We also extend our 2-hop relay networks results to multihop wireless networks by providing a linear
Heuristic Continuous Base Flow Separation Jozsef Szilagyi1
Szilagyi, Jozsef
Heuristic Continuous Base Flow Separation Jozsef Szilagyi1 Abstract: A digital filtering algorithm 1994 and aquifer characterization Brutsaert and Nie- ber 1977; Troch et al. 1993; Szilagyi et al. 1998; Wittenberg and Sivapalan 1999; Szilagyi et al. 2003 , which is crucial in ascertaining safe yields of water
Weakly dispersive hydraulic flows in a contraction --Nonlinear stability analysis
Ee, Bernard Kuowei
Weakly dispersive hydraulic flows in a contraction -- Nonlinear stability analysis Bernard K. Ee hydraulic solutions of the forced Korteweg de-Vries equation is investigated here. For numerical convenience is destabilized by a hydraulic instability in which superexponential growth occurs prior to satura- tion
university-logo Numerical stability analysis for thin film flow
Marzuola, Jeremy
university-logo Numerical stability analysis for thin film flow: toward rigorous verification Blake Barker Indiana University October 2, 2013 B. Rigorous verification #12;university-logo Viscous roll waves (Picture courtesy Neil Balmforth, UBC.) B. Rigorous verification #12;university-logo Viscous roll waves 0 2
Microcomputer analysis of regenerative heat exchangers for oscillating flow
Hutchinson, R.A.; Lyke, S.E.
Regenerative heat exchangers for use in oscillating flows such as those occurring in Stirling engines present considerable analytical problems to the thermal engineer. A simplified finite element analysis has been implemented in a spreadsheet, providing improved access to analytical assumptions and allowing parametric analysis of current heat transfer data. In addition, an irreversibility analysis has been implemented using the thermal and friction results in the spreadsheet. It is suited for evaluation and insights into loss tradeoffs inside operating regenerators, to suggest new regenerator design concepts, and to focus experimental work. 22 refs., 13 figs.
Lyapunov-Based Stability Analysis for REM Congestion Control
Low, Steven H.
Lyapunov-Based Stability Analysis for REM Congestion Control Orhan CĖ . IMER, Tamer BASĖAR Abstract-- This paper investigates convergence properties of basic REM flow control algorithm via Lyapunov functions a Lyapunov argument. Extension to the general multi-link model is discussed as well. I. INTRODUCTION
Stability Analysis of Large-Scale Incompressible Flow Calculations on Massively Parallel Computers 1 Stability Analysis of Large-
Stability Analysis of Large-Scale Incompressible Flow Calculations on Massively Parallel Computers 1 Stability Analysis of Large- Scale Incompressible Flow Calculations on Massively Parallel disturbances aligned with the associated eigenvectors will grow. The Cayley transformation, cou- pled
Energy flow lines as light paths a didactical analysis
Horn, M E
Analyses of interviews with secondary school students about their conceptions of light at the University of Potsdam indicate that numerous students have a deterministic view of light. With regard to these results the model of energy flow lines, which has been discussed recently in the didactical literature, is of special interest. Following this model, light is presumed to move along energy flow lines as trajectories. In an analysis of the model of energy flow lines four didactical dimensions (didactical content, internal structure, present-day relevance and future significance) are investigated. It can be shown that a discussion of this model in physics at school can increase the meta-conceptional knowledge of the students about the models of light. On the other hand, this can promote deterministic conceptions and the Bohm interpretation of quantum mechanics. But the question remains: Should the nature of light really be described as deterministic?
AnalyzeHOLE: An Integrated Wellbore Flow Analysis Tool
Keith J. Halford
Conventional interpretation of flow logs assumes that hydraulic conductivity is directly proportional to flow change with depth. However, well construction can significantly alter the expected relation between changes in fluid velocity and hydraulic conductivity. Strong hydraulic conductivity contrasts between lithologic intervals can be masked in continuously screened wells. Alternating intervals of screen and blank casing also can greatly complicate the relation between flow and hydraulic properties. More permeable units are not necessarily associated with rapid fluid-velocity increases. Thin, highly permeable units can be misinterpreted as thick and less permeable intervals or not identified at all. These conditions compromise standard flow-log interpretation because vertical flow fields are induced near the wellbore. AnalyzeHOLE, an integrated wellbore analysis tool for simulating flow and transport in wells and aquifer systems, provides a better alternative for simulating and evaluating complex well-aquifer system interaction. A pumping well and adjacent aquifer system are simulated with an axisymmetric, radial geometry in a two-dimensional MODFLOW model. Hydraulic conductivities are distributed by depth and estimated with PEST by minimizing squared differences between simulated and measured flows and drawdowns. Hydraulic conductivity can vary within a lithology but variance is limited with regularization. Transmissivity of the simulated system also can be constrained to estimates from single-well, pumping tests. Water-quality changes in the pumping well are simulated with simple mixing models between zones of differing water quality. These zones are differentiated by backtracking thousands of particles from the well screens with MODPATH. An Excel spreadsheet is used to interface the various components of AnalyzeHOLE by (1) creating model input files, (2) executing MODFLOW, MODPATH, PEST, and supporting FORTRAN routines, and (3) importing and graphically displaying pertinent results.
A MultiPhase Power Flow Model for Grid Analysis A. P. Sakis Meliopoulos
A MultiPhase Power Flow Model for ĄĄĄĄGrid Analysis A. P. Sakis Meliopoulos School of Electrical multiphase power flow analysis method that provides exact solution to the operation of the ĄGrid under steady
228 POWER FLOW ANALYSIS parties, it is crucial to recognize the inherently subjective nature of OPF. Power flow
Kammen, Daniel M.
228 POWER FLOW ANALYSIS parties, it is crucial to recognize the inherently subjective nature of OPF. Power flow analysis by itself basically answers a question of physics. By contrast, OPF answers criteria. In short, "optim- ality" does not arise from a power system's intrinsic technical properties
Redox flow batteries based on supporting solutions containing chloride
Li, Liyu; Kim, Soowhan; Yang, Zhenguo; Wang, Wei; Zhang, Jianlu; Chen, Baowei; Nie, Zimin; Xia, Guanguang
Redox flow battery systems having a supporting solution that contains Cl.sup.- ions can exhibit improved performance and characteristics. Furthermore, a supporting solution having mixed SO.sub.4.sup.2- and Cl.sup.- ions can provide increased energy density and improved stability and solubility of one or more of the ionic species in the catholyte and/or anolyte. According to one example, a vanadium-based redox flow battery system is characterized by an anolyte having V.sup.2+ and V.sup.3+ in a supporting solution and a catholyte having V.sup.4+ and V.sup.5+ in a supporting solution. The supporting solution can contain Cl.sup.- ions or a mixture of SO.sub.4.sup.2- and Cl.sup.- ions.
Physics-Based, Reduced-Order Combustor Flow Modeling Sean D. Bradshaw
Peraire, Jaime
Physics-Based, Reduced-Order Combustor Flow Modeling by Sean D. Bradshaw B.S., Aeronautics-Based, Reduced-Order Combustor Flow Modeling by Sean D. Bradshaw Submitted to the Department of Aeronautics in Aeronautics And Astronautics Abstract A physics-based, reduced-order combustor flow model, CFLOW, is described
Paris-Sud XI, Universitķ de
ATTEMPT OF ALPINE GLACIER FLOW MODELING BASED ON CORRELATION MEASUREMENTS OF HIGH RESOLUTION SAR In this paper, an attempt of Alpine glacier flow modeling is performed based on a series of high resolution TerraSAR-X SAR images and a Digital Elevation Model. First, a glacier flow model is established
The backward phase flow and FBI-transform-based Eulerian Gaussian beams for the Schrdinger equation
Soatto, Stefano
The backward phase flow and FBI-transform-based Eulerian Gaussian beams for the Schr÷dinger beam FBI transform Reinitialization Schr÷dinger Backward phase flow a b s t r a c t We propose the backward phase flow method to implement the FourierŁBrosŁIagolnitzer (FBI)-transform-based Eulerian
A Flow-Channel Analysis for the Mars Hopper
W. Spencer Cooley
The Mars Hopper is an exploratory vehicle designed to fly on Mars using carbon dioxide from the Martian atmosphere as a rocket propellant. The propellent gasses are thermally heated while traversing a radioisotope ther- mal rocket (RTR) engineÆs core. This core is comprised of a radioisotope surrounded by a heat capacitive material interspersed with tubes for the propellant to travel through. These tubes, or flow channels, can be manu- factured in various cross-sectional shapes such as a special four-point star or the traditional circle. Analytical heat transfer and computational fluid dynamics (CFD) anal- yses were performed using flow channels with either a circle or a star cross- sectional shape. The nominal total inlet pressure was specified at 2,805,000 Pa; and the outlet pressure was set to 2,785,000 Pa. The CO2 inlet tem- perature was 300 K; and the channel wall was 1200 K. The steady-state CFD simulations computed the smooth-walled star shapeÆs outlet temper- ature to be 959 K on the finest mesh. The smooth-walled circleÆs outlet temperature was 902 K. A circle with a surface roughness specification at 0.01 mm gave 946 K and at 0.1 mm yielded 989 K. The The effects of a slightly varied inlet pressure were also examined. The analytical calculations were based on the mass flow rates computed in the CFD simulations and provided significantly higher outlet temperature results while displaying the same comparison trends. Research relating to the flow channel heat transfer studies was also done. Mathematical methods to geometrically match the cross-sectional areas of the circle and star, along with a square and equilateral triangle, were derived. A Wolfram Mathematica 8 module was programmed to analyze CFD results using Richardson Extrapolation and calculate the grid convergence index (GCI). A Mathematica notebook, also composed, computes and graphs the bulk mean temperature along a flow channelÆs length while the user dynam- ically provides the input variables, allowing their effects on the temperature to be more easily observed.
Characterization of fracture networks for fluid flow analysis
Long, J.C.S.; Billaux, D.; Hestir, K.; Majer, E.L.; Peterson, J.; Karasaki, K.; Nihei, K.; Gentier, S.; Cox, L.
The analysis of fluid flow through fractured rocks is difficult because the only way to assign hydraulic parameters to fractures is to perform hydraulic tests. However, the interpretation of such tests, or ''inversion'' of the data, requires at least that we know the geometric pattern formed by the fractures. Combining a statistical approach with geophysical data may be extremely helpful in defining the fracture geometry. Cross-hole geophysics, either seismic or radar, can provide tomograms which are pixel maps of the velocity or attenuation anomalies in the rock. These anomalies are often due to fracture zones. Therefore, tomograms can be used to identify fracture zones and provide information about the structure within the fracture zones. This structural information can be used as the basis for simulating the degree of fracturing within the zones. Well tests can then be used to further refine the model. Because the fracture network is only partially connected, the resulting geometry of the flow paths may have fractal properties. We are studying the behavior of well tests under such geometry. Through understanding of this behavior, it may be possible to use inverse techniques to refine the a priori assignment of fractures and their conductances such that we obtain the best fit to a series of well test results simultaneously. The methodology described here is under development and currently being applied to several field sites. 4 refs., 14 figs.
Robust Extraction Interface for Coupling Droplet-Based and Continuous Flow Microfluidics
Sun, Xuefei; Tang, Keqi; Smith, Richard D.; Kelly, Ryan T.
Reliable and highly efficient extraction of droplets from oil to aqueous phase is key for downstream coupling with chemical separations and nonoptical detection methods such as amperometry and mass spectrometry. This paper presents an improved interface providing robust extraction for droplet-based poly(dimethylsiloxane) (PDMS) microfluidic devices. The extraction interface consists of an array of cylindrical posts with narrow apertures in between. The aqueous flow channel into which droplets coalesced was simply and selectively modified to be hydrophilic, while the continuous oil phase flow channel that contained encapsulated aqueous droplets retained a hydrophobic surface. The different surfaces on both sides of the extraction region form a highly stable liquid interface between the two immiscible phases, allowing rapid droplet transfer to the aqueous stream. Entire droplets could be completely extracted within broad ranges of aqueous and oil flow rates (0 - 1 and 0.1 - 1 uL/min, respectively). After extraction, the droplet contents could be transported electrophoretically or by pressure-driven flow to a monolithically integrated emitter for nano-electrospray ionization mass spectrometry (nanoESI-MS) analysis. This interface should be amenable to the separation and identification of droplet contents and on-line monitoring of in-droplet reactions.
1992 Columbia River Salmon Flow Measures Options Analysis/EIS.
Not Available
This Options Analysis/Environmental Impact Statement (OA/EIS) identifies, presents effects of, and evaluates the potential options for changing instream flow levels in efforts to increase salmon populations in the lower Columbia and Snake rivers. The potential actions would be implemented during 1992 to benefit juvenile and adult salmon during migration through eight run-of-river reservoirs. The Corps of Engineers (Corps) prepared this document in cooperation with the Bonneville Power Administration and the Bureau of Reclamation. The US Fish and Wildlife Service (FSWS) is a participating agency. The text and appendices of the document describe the characteristics of 10 Federal projects and one private water development project in the Columbia River drainage basin. Present and potential operation of these projects and their effects on the salmon that spawn and rear in the Columbia and Snake River System are presented. The life history, status, and response of Pacific salmon to current environmental conditions are described.
Analysis of a Darcy flow model with a dynamic pressure saturation relation \\Lambda
Hulshof, Joost
equations modelling the flow. In the standard approach for two phase flows, such as oilŁwater or airŁwater mixtures, one combines the mass conservation equations and Darcy's law for the separate phasesAnalysis of a Darcy flow model with a dynamic pressure saturation relation \\Lambda Josephus Hulshof
Accident Analysis and Prevention 36 (2004) 933946 Freeway safety as a function of traffic flow
Detwiler, Russell
Accident Analysis and Prevention 36 (2004) 933Ł946 Freeway safety as a function of traffic flow of strong relationships between traffic flow conditions and the likelihood of traffic accidents (crashes reserved. Keywords: Traffic safety; Accident rates; Traffic flow; Loop detectors; Speed; Traffic density
High throughput analysis of samples in flowing liquid
Ambrose, W. Patrick (Los Alamos, NM); Grace, W. Kevin (Los Alamos, NM); Goodwin, Peter M. (Los Alamos, NM); Jett, James H. (Los Alamos, NM); Orden, Alan Van (Fort Collins, CO); Keller, Richard A. (White Rock, NM)
Apparatus and method enable imaging multiple fluorescent sample particles in a single flow channel. A flow channel defines a flow direction for samples in a flow stream and has a viewing plane perpendicular to the flow direction. A laser beam is formed as a ribbon having a width effective to cover the viewing plane. Imaging optics are arranged to view the viewing plane to form an image of the fluorescent sample particles in the flow stream, and a camera records the image formed by the imaging optics.
Trace analysis of atmospheric organic bases
Clark, Dwayne C.
chromatographic fractions for NS analyses ( 121) and its use as a thin layer chromatography (TLC) adsorbent ( 122). The National Institute of Occupational Safety and Health (NIOSH) recommends its use in the analysis of many industrial vapors ( 113 - 120... analysis of atmospheric organic bases were investigated; the study included (1) the analysis of submarine charcoal filter bed samples for nitrogen bases and (2) the use of metallic tetraphenylporphines (TPP) as specific adsorbents for atmospheric...
Symmetry group analysis of an ideal plastic flow
Vincent Lamothe
In this paper, we study the Lie point symmetry group of a system describing an ideal plastic plane flow in two dimensions in order to find analytical solutions. The infinitesimal generators that span the Lie algebra for this system are obtained. We completely classify the subalgebras of up to codimension two in conjugacy classes under the action of the symmetry group. Based on invariant forms, we use Ansatzes to compute symmetry reductions in such a way that the obtained solutions cover simultaneously many invariant and partially invariant solutions. We calculate solutions of the algebraic, trigonometric, inverse trigonometric and elliptic type. Some solutions depending on one or two arbitrary functions of one variable have also been found. In some cases, the shape of a potentially feasible extrusion die corresponding to the solution is deduced. These tools could be used to thin, curve, undulate or shape a ring in an ideal plastic material.
MINET: transient analysis of fluid-flow and heat-transfer networks
Van Tuyle, G.J.; Guppy, J.G.; Nepsee, T.C.
MINET, a computer code developed for the steady-state and transient analysis of fluid-flow and heat-transfer networks, is described. The code is based on a momentum integral network method, which offers significant computational advantages in the analysis of large systems, such as the balance of plant in a power-generating facility. An application is discussed in which MINET is coupled to the Super System Code (SSC), an advanced generic code for the transient analysis of loop- or pool-type LMFBR systems. In this application, the ability of the Clinch River Breeder Reactor Plant to operate in a natural circulation mode following an assumed loss of all electric power, was assessed. Results from the MINET portion of the calculations are compared against those generated independently by the Clinch River Project, using the DEMO code.
Numeric Simulation of Heat Transfer and Electrokinetic Flow in an Electroosmosis-Based
Le Roy, Robert J.
Numeric Simulation of Heat Transfer and Electrokinetic Flow in an Electroosmosis-Based Continuous is dedicated to under- standing the fluid flow and heat transfer mechanisms occurring in continuous flow PCR are discussed in detail. The importance of each heat transfer mechanism for different situations is also
Time evolution of electron flow in a model diode: Non-perturbative analysis
Rokhlenko, A.; Lebowitz, J. L. [Department of Mathematics, Rutgers University, Piscataway, New Jersey 08854-8019 (United States)
Using a combination of Eulerian and Lagrangian variables we study the time evolution of the electron flow from a no-current state to a final state with the stationary current in a planar one-dimensional diode. The electrons can be injected externally or generated by the cathode via field emission governed by a current-field law. The initial zero current regime is replaced suddenly by injection or, in the case of field emission, by jumping the anode voltage from zero to a constant positive value. The case of equipotential electrodes and fixed injection is studied along with a positive anode potential. When the current is fixed externally, the approach to the stationary state goes without oscillations if the initial electron velocity is high enough and the anode can absorb the injected flow. Otherwise the accumulated space charge creates a potential barrier which reflects the flow and leads to its oscillations, but our method of analysis is invalid in such conditions. In the field emission case the flow goes to its stationary state through a train of decaying oscillations whose period is of the order of the electron transit time, in agreement with earlier studies based on perturbation techniques. Our approximate method does not permit very high cathode emissivity although the method works when the stationary current density is only about 10% smaller than the Child-Langmuir limit.
Flow Measurement with Tangential Paddlewheel Flow Meters: Analysis of Experimental Results and in-situ Diagnostics
Watt, J. B.; Haberl, J. S.
the premature drop-out of magnetic-type tangential paddlewheel sensors, as well as several in-situ diagnostic measures for ascertaining whether or not a flow meter is experiencing turbulent conditions or if a flow sensor's output signal is suffering a degraded... per second for magnetic-type, and 0.5 to 2 feet per second for non-magnetic-type flow sensors deviated from the actual flow by 20% or more which makes the measurement of flow and thermal energy use in this regime highly suspect. Figure 4 also indicates...
Visualization of Intricate Flow Structures for Vortex Breakdown Analysis Xavier Tricoche
Utah, University of
Visualization of Intricate Flow Structures for Vortex Breakdown Analysis Xavier Tricoche University, synthetic depictions that permit new insight into the structural properties of vortex breakdowns. CR And Modeling-- Simulation Output Analysis J.2 [Physical Sciences and Engineer- ing]: Engineering--. Keywords
Bubble Size Control to Improve Oxygen-Based Bleaching: Characterization of Flow Regimes in Pulp-Water-Gas Three-Phase Flows
S.M. Ghiaasiaan and Seppo Karrila
Flow characteristics of fibrous paper pulp-water-air slurries were investigated in a vertical circular column 1.8 m long, with 5.08 cm diameter. Flow structures, gas holdup (void fraction), and the geometric and population characteristics of gas bubbles were experimentally investigated, using visual observation, Gamma-ray densitometry, and flash X-ray photography. Five distinct flow regimes could be visually identified: dispersed bubbly, layered bubbly, plug, churn-turbulent, and slug. Flow regime maps were constructed, and the regime transition lines were found to be sensitive to consistency. The feasibility of using artificial neural networks (ANNs) for the identification of the flow regimes, using the statistical characteristics of pressure fluctuations measured by a single pressure sensor, was demonstrated. Local pressure fluctuations at a station were recorded with a minimally-intrusive transducer. Three-layer, feed-forward ANNs were designed that could identify the four major flow patterns (bubbly, plug, churn, and slug) well. The feasibility of a transportable artificial neural network (ANN) - based technique for the classification of flow regimes was also examined. Local pressures were recorded at three different locations using three independent but similar transducers. An ANN was designed, trained and successfully tested for the classification of the flow regimes using one of the normalized pressure signals (from Sensor 1). The ANN trained and tested for Sensor 1 predicted the flow regimes reasonably well when applied directly to the other two sensors, indicating a good deal of transportability. An ANN-based method was also developed, whereby the power spectrum density characteristics of other sensors were adjusted before they were used as input to the ANN that was based on Sensor 1 alone. The method improved the predictions. The gas-liquid interfacial surface area concentration was also measured in the study. The gas absorption technique was applied, using CO2 as the transferred species and sodium hydroxide as the alkaline agent in water. Statistical analysis was performed to identify the parametric dependencies. The experimental data were empirically correlated.
Agent-Based Modeling and Simulation for Hydrogen Transition Analysis...
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Agent-Based Modeling and Simulation for Hydrogen Transition Analysis Agent-Based Modeling and Simulation for Hydrogen Transition Analysis Presentation on Agent-Based Modeling and...
A review and development of correlations for base pressure and base heating in supersonic flow
Lamb, J.P. [Texas Univ., Austin, TX (United States). Dept. of Mechanical Engineering; Oberkampf, W.L. [Sandia National Labs., Albuquerque, NM (United States)
A comprehensive review of experimental base pressure and base heating data related to supersonic and hypersonic flight vehicles has been completed. Particular attention was paid to free-flight data as well as wind tunnel data for models without rear sting support. Using theoretically based correlation parameters, a series of internally consistent, empirical prediction equations has been developed for planar and axisymmetric geometries (wedges, cones, and cylinders). These equations encompass the speed range from low supersonic to hypersonic flow and laminar and turbulent forebody boundary layers. A wide range of cone and wedge angles and cone bluntness ratios was included in the data base used to develop the correlations. The present investigation also included preliminary studies of the effect of angle of attack and specific-heat ratio of the gas.
Electrochimica Acta 50 (2005) 53905398 Membraneless laminar flow-based micro fuel cells operating in alkaline,
Kenis, Paul J. A.
Electrochimica Acta 50 (2005) 5390Ł5398 Membraneless laminar flow-based micro fuel cells operating) in membraneless, laminar flow-based micro fuel cells (LF-FCs) eliminates several PEM-related issues such as fuel the anode is in acidic media while the cathode is in alkali, or vice versa. Operating a fuel cell under
Analysis of pressure drops under reversing flow conditions
Krazinski, J.L.; Holtz, R.E.; Uherka, K.L.; Lottes, P.A.
This paper examines pressure-drop data from the Reversing Flow Test Facility (RFTF) at Argonne National Laboratory (ANL). The data comprise part of an initial series of measurements conducted with pressurized helium gas under reversing flow conditions. The characteristics of fluid pressure drops in compressible, reversing flows are discussed in the paper and compared with pressure-drop measurements for steady, incompressible flows. The methodology used to calculate instantaneous mass flows in the test section of the RFTF is summarized. The measured pressure drops are analyzed in terms of their frictional and inertial components. Pressure-drop data are presented for both tubes and wire mesh regenerators over a range of flow reversal frequencies. The results are discussed with reference to other experimental data and analytical models available in the literature. 10 refs., 6 figs., 2 tabs.
Dispersed Fluid Flow in Fractured Reservoirs- an Analysis of...
Distributions Abstract A methodology for analyzing the internal flow characteristics of a fractured geothermal reservoir using tracer-determined residence time distribution curves...
Edge-based Meshless Methods for Compressible Flow Simulations
Jameson, Antony
are obtained for airfoils in transonic flow. Lift and drag coefficients also compare well to the finite volume, including (1) the application of certain artificial diffusion schemes to meshless methods within an edge
Geographically-Based Infrastructure Analysis
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport inEnergy0.pdfTechnologiesNATIONAL003Not MeasurementDeepGeographically Based
Stochastic Simulations and Sensitivity Analysis of Plasma Flow
Lin, Guang; Karniadakis, George E.
For complex physical systems with large number of random inputs, it will be very expensive to perform stochastic simulations for all of the random inputs. Stochastic sensitivity analysis is introduced in this paper to rank the significance of random inputs, provide information on which random input has more influence on the system outputs and the coupling or interaction effect among different random inputs. There are two types of numerical methods in stochastic sensitivity analysis: local and global methods. The local approach, which relies on a partial derivative of output with respect to parameters, is used to measure the sensitivity around a local operating point. When the system has strong nonlinearities and parameters fluctuate within a wide range from their nominal values, the local sensitivity does not provide full information to the system operators. On the other side, the global approach examines the sensitivity from the entire range of the parameter variations. The global screening methods, based on One-At-a-Time (OAT) perturbation of parameters, rank the significant parameters and identify their interaction among a large number of parameters. Several screening methods have been proposed in literature, i.e., the Morris method, Cotter's method, factorial experimentation, and iterated fractional factorial design. In this paper, the Morris method, Monte Carlo sampling method, Quasi-Monte Carlo method and collocation method based on sparse grids are studied. Additionally, two MHD examples are presented to demonstrate the capability and efficiency of the stochastic sensitivity analysis, which can be used as a pre-screening technique for reducing the dimensionality and hence the cost in stochastic simulations.
Lindner, Douglas K.
is developed with includes a dynamic structural model of the actuator, a dynamic model of the power electronics. It is shown that an outer acoustic control loop can modify this mechanical admittance and optimize the power, the power flow between the electrical and mechanical systems is analyzed through simulation. The flow
algorithms to handle this problem for the e - 1 security constrained optimal power flow problem. We also.3. The MATPOWER package 4 2.4. Graph theoretic notions 4 3. Security constrained optimal power flow 5 3, such as the breakdown of a generator or a fault in some transmission line. The importance of being able to supply power
Uncertainty Analysis for a Virtual Flow Meter Using an Air-Handling Unit Chilled Water Valve
Song, Li; Wang, Gang; Brambley, Michael R.
A virtual water flow meter is developed that uses the chilled water control valve on an air-handling unit as a measurement device. The flow rate of water through the valve is calculated using the differential pressure across the valve and its associated coil, the valve command, and an empirically determined valve characteristic curve. Thus, the probability of error in the measurements is significantly greater than for conventionally manufactured flow meters. In this paper, mathematical models are developed and used to conduct uncertainty analysis for the virtual flow meter, and the results from the virtual meter are compared to measurements made with an ultrasonic flow meter. Theoretical uncertainty analysis shows that the total uncertainty in flow rates from the virtual flow meter is 1.46% with 95% confidence; comparison of virtual flow meter results with measurements from an ultrasonic flow meter yielded anuncertainty of 1.46% with 99% confidence. The comparable results from the theoretical uncertainty analysis and empirical comparison with the ultrasonic flow meter corroborate each other, and tend to validate the approach to computationally estimating uncertainty for virtual sensors introduced in this study.
Modeling of stagnation-line nonequilibrium flows by means of quantum based collisional models
Munaf", A., E-mail: firstname.lastname@example.com; Magin, T. E., E-mail: email@example.com [Aeronautics and Aerospace Department, von Karman Institute for Fluid Dynamics, 1640 Rhode-Saint-GenĶse (Belgium)
The stagnation-line flow over re-entry bodies is analyzed by means of a quantum based collisional model which accounts for dissociation and energy transfer in N{sub 2}-N interactions. The physical model is based on a kinetic database developed at NASA Ames Research Center. The reduction of the kinetic mechanism is achieved by lumping the rovibrational energy levels of the N{sub 2} molecule in energy bins. The energy bins are treated as separate species, thus allowing for non-Boltzmann distributions of their populations. The governing equations are discretized in space by means of the Finite Volume method. A fully implicit time-integration is used to obtain steady-state solutions. The results show that the population of the energy bins strongly deviate from a Boltzmann distribution close to the shock wave and across the boundary layer. The sensitivity analysis to the number of energy bins reveals that accurate estimation of flow quantities (such as chemical composition and wall heat flux) can be obtained by using only 10 energy bins. A comparison with the predictions obtained by means of conventional multi-temperature models indicates that the former can lead to an overestimation of the wall heat flux, due to an inaccurate modeling of recombination in the boundary layer.
Time series power flow analysis for distribution connected PV generation.
Broderick, Robert Joseph; Quiroz, Jimmy Edward; Ellis, Abraham; Reno, Matthew J. [Georgia Institute of Technology, Atlanta, GA; Smith, Jeff [Electric Power Research Institute, Knoxville, TN; Dugan, Roger [Electric Power Research Institute, Knoxville, TN
Distributed photovoltaic (PV) projects must go through an interconnection study process before connecting to the distribution grid. These studies are intended to identify the likely impacts and mitigation alternatives. In the majority of the cases, system impacts can be ruled out or mitigation can be identified without an involved study, through a screening process or a simple supplemental review study. For some proposed projects, expensive and time-consuming interconnection studies are required. The challenges to performing the studies are twofold. First, every study scenario is potentially unique, as the studies are often highly specific to the amount of PV generation capacity that varies greatly from feeder to feeder and is often unevenly distributed along the same feeder. This can cause location-specific impacts and mitigations. The second challenge is the inherent variability in PV power output which can interact with feeder operation in complex ways, by affecting the operation of voltage regulation and protection devices. The typical simulation tools and methods in use today for distribution system planning are often not adequate to accurately assess these potential impacts. This report demonstrates how quasi-static time series (QSTS) simulation and high time-resolution data can be used to assess the potential impacts in a more comprehensive manner. The QSTS simulations are applied to a set of sample feeders with high PV deployment to illustrate the usefulness of the approach. The report describes methods that can help determine how PV affects distribution system operations. The simulation results are focused on enhancing the understanding of the underlying technical issues. The examples also highlight the steps needed to perform QSTS simulation and describe the data needed to drive the simulations. The goal of this report is to make the methodology of time series power flow analysis readily accessible to utilities and others responsible for evaluating potential PV impacts.
Evaluation of Stallion Sperm Membrane Integrity Using Varied Flow Cytometer-Based Methodologies
Stump, Karen Elizabeth
. Data were collected daily on sperm motion characteristics, SMI, mitochondrial membrane potential, and DNA quality. To measure daily changes in SMI in stallion sperm, two fluorescent vital-staining protocols used in flow cytometric analysis were...
To cite this version : Rigo-Mariani, Rmy and Sareni, Bruno and Roboam, Xavier Fast Power Flow Scheduling and Sensitivity Analysis for Sizing a
Paris-Sud XI, Universitķ de
for optimal dispatching of power flows in a microgrid with storage. The investigated approach is based Scheduling and Sensitivity Analysis for Sizing a Microgrid with Storage. (2014) In: 11th International ANALYSIS FOR SIZING A MICROGRID WITH STORAGE R. Rigo-Mariani1 , B. Sareni1 , X. Roboam1 1. Universitķ de
Throughput-cost analysis of optical flow switching
Chan, Vincent W. S.
In this paper, we employ a cost model embodying major sources of capital expenditure (CapEx) to compare the throughput-cost tradeoff offered by optical flow switching to that of more traditional optical network architectures.
Analysis of two- and three-dimensional flow separation
Grunberg, Olivier, 1978-
Prandtl (1904) showed that streamlines in a steady flow past a two-dimensional streamlined body separate from the boundary where the skin friction (or wall shear) vanishes and admits a negative gradient. Although commonly ...
ōBatchö Kinetics in Flow: Online IR Analysis and Continuous Control
Moore, Jason S.
Currently, kinetic data is either collected under steady-state conditions in flow or by generating time-series data in batch. Batch experiments are generally considered to be more suitable for the generation of kinetic ...
Development of flow network analysis code for block type VHTR core by linear theory method
Lee, J. H.; Yoon, S. J. [Dept. of Nuclear Engr., Seoul National Univ., Daehak-dong, Gwanak-gu, Seoul, 151-742 (Korea, Republic of); Park, J. W. [Dept. of Nuclear and Energy Engr, Dongguk Univ., Seokjang-Dong, Gyeongju, Gyeongsangbuk-Do, 780-714 (Korea, Republic of); Park, G. C. [Dept. of Nuclear Engr., Seoul National Univ., Daehak-dong, Gwanak-gu, Seoul, 151-742 (Korea, Republic of)
VHTR (Very High Temperature Reactor) is high-efficiency nuclear reactor which is capable of generating hydrogen with high temperature of coolant. PMR (Prismatic Modular Reactor) type reactor consists of hexagonal prismatic fuel blocks and reflector blocks. The flow paths in the prismatic VHTR core consist of coolant holes, bypass gaps and cross gaps. Complicated flow paths are formed in the core since the coolant holes and bypass gap are connected by the cross gap. Distributed coolant was mixed in the core through the cross gap so that the flow characteristics could not be modeled as a simple parallel pipe system. It requires lot of effort and takes very long time to analyze the core flow with CFD analysis. Hence, it is important to develop the code for VHTR core flow which can predict the core flow distribution fast and accurate. In this study, steady state flow network analysis code is developed using flow network algorithm. Developed flow network analysis code was named as FLASH code and it was validated with the experimental data and CFD simulation results. (authors)
An Analysis of Heat and Fluid Flow Phenomena 1n Electroslag Welding
Eagar, Thomas W.
and temperature distri- bution~ are given for several idealized models of the electroslag welding process) ) An Analysis of Heat and Fluid Flow Phenomena 1n Electroslag Welding Two physical models created and fluid flow phenom- ena in metals processing operations have been applied to electroslag weld- ing
Effects of non-Darcy flow on pressure buildup analysis of hydraulically fractured gas reservoirs
Alvarez Vera, Cesar
-Darcy flow in the hydraulic fracture and its effects on pressure buildup analysis of hydraulically fractured gas reservoirs. A reservoir simulator was used to generate pressure drawdown and buildup data both with and without the effects of non-Darcy flow...
Development of a Parallel FVM based Groundwater Flow Model
Cirpka, Olaf Arie
. In this equation v denotes the Darcy-velocity of the uid (water) [m=s], q denotes the source / sink term [m 3 =(m. The momentum equation is simpli#12;ed yielding the well-known Darcy's Law: v = k f #3; grad h (2 Groundwater Flow Equation The continuity equation for stationary groundwater ow is given by: Z divf#26; #3
Active Gaze Control Improves Optic Flow-Based Segmentation and Steering
Neumann, Heiko
Active Gaze Control Improves Optic Flow-Based Segmentation and Steering Florian Raudies1,2 *, Ennio research on optic flow revealed its invariant properties and influence on steering control. This early. To support our suggestion we derive an analytical model that shows: Tangentially fixating the outer surface
Incorporating and Evaluating Environmental Instream Flows in a Priority Order Based Surface Water Allocation Model
Pauls, Mark
............................................................................................................ 120 Figure 20. Comparison of Engaged Period Reliability versus Allowable Deficit (M3B) between Trinity WAM Control Points for All Instream Flow Targets... INCORPORATING AND EVALUATING ENVIRONMENTAL INSTREAM FLOWS IN A PRIORITY ORDER BASED SURFACE WATER ALLOCATION MODEL A Thesis by MARK ALLEN PAULS Submitted to the Office of Graduate and Professional Studies of Texas A&M University...
Journal of Power Sources 128 (2004) 5460 Microfluidic fuel cell based on laminar flow
Kenis, Paul J. A.
Journal of Power Sources 128 (2004) 54Ł60 Microfluidic fuel cell based on laminar flow Eric R a novel microfluidic fuel cell concept that utilizes the occurrence of multi-stream laminar flow turbulent mixing. Preliminary results indicate that this novel fuel cell concept may lead to the development
Framework for the Economic Analysis of Hybrid Systems Based on Exergy Consumption
Cristian Rabiti; Robert S. Cherry; Wesley R. Deason; Piyush Sabharwall; Shannon M. Bragg-Sitton; Richard D. Boardman
Starting from an overview of the dynamic behavior of the electricity market the need of the introduction of energy users that will provide a damping capability to the system is derived as also a qualitative analysis of the impact of uncertainty, both in the demand and supply side, is performed. Then it follows an introduction to the investment analysis methodologies based on the discounting of the cash flow, and then work concludes with the illustration and application of the exergonomic principles to provide a sound methodology for the cost accounting of the plant components to be used in the cash flow analysis.
Performance Analysis of an Annular Diffuser Under the Influence of a Gas Turbine Stage Exit Flow
Blanco, Rafael Rodriguez
In this investigation the performance of a gas turbine exhaust diffuser subject to the outlet flow conditions of a turbine stage is evaluated. Towards that goal, a fully three-dimensional computational analysis has been performed where several...
IN THE COSO GEOTHERMAL FIELD Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Proceedings: IN SITU STRESS, FRACTURE, AND FLUID FLOW ANALYSIS IN WELL...
OF THE COSO GEOTHERMAL FIELD Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Proceedings: IN SITU STRESS, FRACTURE AND FLUID FLOW ANALYSIS-EAST...
An Equivalent Network for Load-Flow Analysis of Power Systems
Johnson, Merion Luke
AN EQUIVALENT NETWORK FOR LOAD-FLOW ANALYSIS OF POWER SYSTEMS A Thesis by Meri on L. Johnson Submitted to the Graduate School of the Agricultural and Mechanical College of Texas in partihl fulfillment of the requirements for the degree...
Analysis of Flow Phenomena in Virtual Environments Benefits, Challenges, and Solutions
Kuhlen, Torsten
) Ł is nowadays an indispensable and essential tool for the development of, e.g., airplanes, cars, combustion engines, turbines etc. Even in medicine, CFD is going to play an important role in the analysis of flow
Carbon flow and ecosystem dynamics in the Mississippi River plume described by inverse analysis
Breed, Greg Allen
for the degree of MASTER OF SCIENCE December 2002 Major Subject: Oceanography CARBON FLOW AND ECOSYSTEM DYNAMICS IN THE MISSISSIPPI RIVER PLUME DESCRIBED BY INVERSE ANALYSIS A Thesis by GREG ALLEN BREED Submitted to Texas A&M University in partial... of Department) December 2002 Major Sublect: Oceanography ABSTRACT Carbon Flow and Ecosystem Dynamics in the Mississippi River Plume Described by Inverse Analysis. (December 2002) Greg Allen Breed, B. S. , University of Minnesota Chair of Advisory...
A finite element viscous flow analysis in a radial turbine scroll
Hill, Donald Lee
A FINITE ELEMENT VISCOUS FLOW ANALYSIS IN A RADIAL TURBINE SCROLL A Thesis DONALD LEE HILL JR. Submitted to the Graduate College. of Texas ASM University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE December... 1987 Major Subject: Mechanical Engineering A FINITE ELEMENT VISCOUS FLOW ANALYSIS IN A RADIAL TURBINE SCROLL A Thesis by DONALD LEE HILL JR. Approved as to style snd content by: Dr. Erian A. Baskharone (Chairman of Conunittee) Dr. Alan B azzolo...
Development of magnetic separation methods of analysis: magnetic field flow fractionation
Garcia-Ramirez, Jaime
DEVELOPMENT OF MAGNETIC SEPARATION METHODS OF ANALYSIS: MAGNETIC FIELD FLOW FRACTIONATION A Thesis by JAIME GARCIA-RAMIREZ Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree... of MASTER OF SCIENCE August 1980 Major Subject: Chemistry DEVELOPMENT OF MAGNETIC SEPARATION METHODS OF ANALYSIS: MAGNETIC FIELD FLOW FRACTIONATION A Thesis by JAIME GARCIA-RAMIREZ Approved as to style and content by: (Chairman of Committee) 1...
Flatness-Based Control of Open-Channel Flow in an Irrigation Canal Using SCADA
Boyer, Edmond
Flatness-Based Control of Open-Channel Flow in an Irrigation Canal Using SCADA Tarek Rabbani, Simon of an algorithm for real-time irrigation operations using a supervision, control, and data acquisition (SCADA
TEMPO-based Catholyte for High Energy Density Nonaqueous Redox Flow Batteries
Wei, Xiaoliang; Xu, Wu; Vijayakumar, M.; Cosimbescu, Lelia; Liu, Tianbiao L.; Sprenkle, Vincent L.; Wang, Wei
We will present a novel design lithium-organic non-aqueous redox flow battery based on a TEMPO catholyte. This RFB produced desired electrochemical performance exceeding most of the currently reported nonaqueous RFB systems.
Free-surface flow simulations for discharge-based operation of hydraulic structure gates
Erdbrink, C D; Sloot, P M A
We combine non-hydrostatic flow simulations of the free surface with a discharge model based on elementary gate flow equations for decision support in operation of hydraulic structure gates. A water level-based gate control used in most of today's general practice does not take into account the fact that gate operation scenarios producing similar total discharged volumes and similar water levels may have different local flow characteristics. Accurate and timely prediction of local flow conditions around hydraulic gates is important for several aspects of structure management: ecology, scour, flow-induced gate vibrations and waterway navigation. The modelling approach is described and tested for a multi-gate sluice structure regulating discharge from a river to the sea. The number of opened gates is varied and the discharge is stabilized with automated control by varying gate openings. The free-surface model was validated for discharge showing a correlation coefficient of 0.994 compared to experimental data. A...
Symbolic Test Selection Based on Approximate Analysis
Paris-Sud XI, Universitķ de
Symbolic Test Selection Based on Approximate Analysis Bertrand Jeannet, Thierry J┤eron, Vlad email@example.com Abstract. This paper addresses the problem of generating symbolic test cases for testing the conformance. The challenge we consider is the selection of test cases according to a test purpose, which is here a set
Self-learning IP Traffic Classification based on Statistical Flow Characteristics
Zander, Sebastian
and intrusion detection. The most common identification technique based on the inspection of `known port numbers or encrypted traffic. The authors of [1] propose signature-based methods to classify P2P traffic. AlthoughSelf-learning IP Traffic Classification based on Statistical Flow Characteristics Sebastian Zander1
Bulk-Flow analysis for force and moment coefficients of a shrouded centrifugal compressor impeller
Gupta, Manoj Kumar
et al. (1996). The comparison shows that the shroud casing clearance flow and the fluid force moment can be simulated by the bulk flow model fairly well. An Iwatsubo-based labyrinth seal code developed by Childs and Scharrer (1986) is used...
Simscape Design Flow for Memristor Based Programmable Oscillators
Mohanty, Saraju P.
oscillator is characterized within the Simscape framework. The oscillation frequency and power consumption of memristor-based oscillators. (2) A Gravitational Search Algorithm (GSA) based optimization algorithm in terms of power consumption and frequency. (4) The first ever Simscape based models for titanium oxide
Analysis of Transient Processes in a Radiophysical Flow System
E. N. Egorov; A. A. Koronovskii; A. E. Hramov
Transient processes in a third-order radiophysical flow system are studied and a map of the transient process duration versus initial conditions is constructed and analyzed. The results are compared to the arrangement of submanifolds of the stable and unstable cycles in the Poincare section of the system studied.
Graphene-based battery electrodes having continuous flow paths
Zhang, Jiguang; Xiao, Jie; Liu, Jun; Xu, Wu; Li, Xiaolin; Wang, Deyu
Some batteries can exhibit greatly improved performance by utilizing electrodes having randomly arranged graphene nanosheets forming a network of channels defining continuous flow paths through the electrode. The network of channels can provide a diffusion pathway for the liquid electrolyte and/or for reactant gases. Metal-air batteries can benefit from such electrodes. In particular Li-air batteries show extremely high capacities, wherein the network of channels allow oxygen to diffuse through the electrode and mesopores in the electrode can store discharge products.
Capacitance-based prover for gas flow meters
Pipkins, Sean Patrick
;?= enthalpy of the air at the inlet. H Uo =U +RT Uo =Cv(T To)+RT, (36) 24 Equation (35) can be written as c (T-T)=[c (T?? T)+RT. , ?] Il ? ' n j (37) Solving Equation (37) for T gives the equation used to calculate the temperature profiles of the air.... . . . . Relation of Capacitance Change to Molar Flow Rate. DiIferential Method Integral Method THEORETICAL CALCULATIONS. Calculated C. Experimental C. Thermal Expansion Effects . . Capacitance Change Due to Length Change Capacitance Change Due to Radius...
Development of a flow injection analysis method for the determination of acrylamide copolymers in oilfield brines
Taylor, K.C.; Burke, R.A.; Schramm, L.L. [Petroleum Recovery Inst., Calgary, Alberta (Canada); Nasr-El-Din, H.A. [Saudi Aramco, Dhahran (Saudi Arabia)
An automated method for the determination of acrylamide polymers by flow injection analysis (FIA) has been developed and optimized for routine use. The method has been extensively tested for interferences common in oilfield brines. Potential interferences were examined from Na{sup +}, Ca{sup 2+}, Cr{sup 3+}, Al{sup 3+}, Zr{sup 3+}, NH{sub 4}{sup +}, Cl{sup {minus}}, OH{sup {minus}}, CO{sub 3}{sup 2{minus}}, sample coloration, and commonly used surfactants. The analysis is specific for amides, and the sensitivity to concentration of amide groups in the polymer was shown to be constant as the degree of polymer hydrolysis was varied. The range of the method is 0.1 to 100 mg/L. Sample throughput is 30 samples/h with triplicate analysis. Relative standard deviations of 0.2% are readily obtained from standard solutions and 0.5% from complex samples (at 50 mg/L). The method is applicable to the determination of aqueous, acrylamide-based polymers in process streams, surface waters and oilfield brines.
A high sensitivity fiber optic macro-bend based gas flow rate transducer for low flow rates: Theory, working principle, and static calibration
Schena, Emiliano; Saccomandi, Paola; Silvestri, Sergio [Center for Integrated Research, Unit of Measurements and Biomedical Instrumentation, Universita Campus Bio-Medico di Roma, Via Alvaro del Portillo, 21, 00128 Rome (Italy)
A novel fiber optic macro-bend based gas flowmeter for low flow rates is presented. Theoretical analysis of the sensor working principle, design, and static calibration were performed. The measuring system consists of: an optical fiber, a light emitting diode (LED), a Quadrant position sensitive Detector (QD), and an analog electronic circuit for signal processing. The fiber tip undergoes a deflection in the flow, acting like a cantilever. The consequent displacement of light spot center is monitored by the QD generating four unbalanced photocurrents which are function of fiber tip position. The analog electronic circuit processes the photocurrents providing voltage signal proportional to light spot position. A circular target was placed on the fiber in order to increase the sensing surface. Sensor, tested in the measurement range up to 10 l min{sup -1}, shows a discrimination threshold of 2 l min{sup -1}, extremely low fluid dynamic resistance (0.17 Pa min l{sup -1}), and high sensitivity, also at low flow rates (i.e., 33 mV min l{sup -1} up to 4 l min{sup -1} and 98 mV min l{sup -1} from 4 l min{sup -1} up to 10 l min{sup -1}). Experimental results agree with the theoretical predictions. The high sensitivity, along with the reduced dimension and negligible pressure drop, makes the proposed transducer suitable for medical applications in neonatal ventilation.
Estimation of the base flow recession constant under human interference
Thomas, Brian F; Vogel, Richard M; Kroll, Charles N; Famiglietti, James S
Geologic controls on ground-water storage and base ?ow, J.law model to relate ground- water storage in an uncon?ned
Robinson, J.
terns on safety and accident analysis since t h i s i s theACCIDENT ANALYSIS ACCIDENT, TRANSPORTATION SAFETY ANALYSISInformation Center Data Base RISK HAZARDS ANALYSIS ACCIDENT
Computational Analysis of Material Flow During Friction Stir Welding of AA5059 Aluminum Alloys
Grujicic, Mica
Computational Analysis of Material Flow During Friction Stir Welding of AA5059 Aluminum Alloys M welding (FSW) process are investigated computationally. Within the numerical model of the FSW process component. The employed coupled Eulerian/Lagrangian computational analysis of the welding process
Harmonic Analysis of a Three-Phase Diode Bridge Rectifier based on Sampled-Data Model
Lehn, Peter W.
Harmonic Analysis of a Three-Phase Diode Bridge Rectifier based on Sampled-Data Model K. L. Lian. As demonstrated in the paper, the proposed method analytically evaluates harmonics, and obtains exact switching is to incorporate it into a harmonic power flow program to yield improved accuracy. Index Terms-- Diode Bridge
Techno-Economic Analysis of Biofuels Production Based on Gasification
Swanson, R. M.; Platon, A.; Satrio, J. A.; Brown, R. C.; Hsu, D. D.
This study compares capital and production costs of two biomass-to-liquid production plants based on gasification. The first biorefinery scenario is an oxygen-fed, low-temperature (870?C), non-slagging, fluidized bed gasifier. The second scenario is an oxygen-fed, high-temperature (1,300?C), slagging, entrained flow gasifier. Both are followed by catalytic Fischer-Tropsch synthesis and hydroprocessing to naphtha-range (gasoline blend stock) and distillate-range (diesel blend stock) liquid fractions. Process modeling software (Aspen Plus) is utilized to organize the mass and energy streams and cost estimation software is used to generate equipment costs. Economic analysis is performed to estimate the capital investment and operating costs. Results show that the total capital investment required for nth plant scenarios is $610 million and $500 million for high-temperature and low-temperature scenarios, respectively. Product value (PV) for the high-temperature and low-temperature scenarios is estimated to be $4.30 and $4.80 per gallon of gasoline equivalent (GGE), respectively, based on a feedstock cost of $75 per dry short ton. Sensitivity analysis is also performed on process and economic parameters. This analysis shows that total capital investment and feedstock cost are among the most influential parameters affecting the PV.
1980 Base case and feasibility analysis
Not Available
This report describes a task of documenting a base case'' and performing a feasibility analysis for a national residential energy efficiency program for new homes, The principal objective of the task wasto estimate the energy consumption of typical homes built in 1980 and then to identify and assess the feasibility of methods to reduce that consumption by 50%. The goal of the program by the year 2000 is to reduce heating and cooling energy use in new homes built under the program to one-half of the energy use in typical new homes built in 1980. The task also calls for determining whether the program goal should be revised, based on the analysis.
1980 Base case and feasibility analysis
This report describes a task of documenting a ``base case`` and performing a feasibility analysis for a national residential energy efficiency program for new homes, The principal objective of the task wasto estimate the energy consumption of typical homes built in 1980 and then to identify and assess the feasibility of methods to reduce that consumption by 50%. The goal of the program by the year 2000 is to reduce heating and cooling energy use in new homes built under the program to one-half of the energy use in typical new homes built in 1980. The task also calls for determining whether the program goal should be revised, based on the analysis.
Development of a cell-based stream flow routing modelĀ
Raina, Rajeev
This study presents the development of a cell-based routing model. The model developed is a two parameter hydrological routing model that uses a coarse resolution stream network to route runoff from each cell in the watershed ...
Materials Flows through Industry (MFI) Tool ┬ģ AMO Analysis Review
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdfBreaking ofOil & GasTechnical Publications ┬╗of EnergyMaterials Flows through
Chapter 11. Community analysis-based methods
Cao, Y.; Wu, C.H.; Andersen, G.L.; Holden, P.A.
Microbial communities are each a composite of populations whose presence and relative abundance in water or other environmental samples are a direct manifestation of environmental conditions, including the introduction of microbe-rich fecal material and factors promoting persistence of the microbes therein. As shown by culture-independent methods, different animal-host fecal microbial communities appear distinctive, suggesting that their community profiles can be used to differentiate fecal samples and to potentially reveal the presence of host fecal material in environmental waters. Cross-comparisons of microbial communities from different hosts also reveal relative abundances of genetic groups that can be used to distinguish sources. In increasing order of their information richness, several community analysis methods hold promise for MST applications: phospholipid fatty acid (PLFA) analysis, denaturing gradient gel electrophoresis (DGGE), terminal restriction fragment length polymorphism (TRFLP), cloning/sequencing, and PhyloChip. Specific case studies involving TRFLP and PhyloChip approaches demonstrate the ability of community-based analyses of contaminated waters to confirm a diagnosis of water quality based on host-specific marker(s). The success of community-based MST for comprehensively confirming fecal sources relies extensively upon using appropriate multivariate statistical approaches. While community-based MST is still under evaluation and development as a primary diagnostic tool, results presented herein demonstrate its promise. Coupled with its inherently comprehensive ability to capture an unprecedented amount of microbiological data that is relevant to water quality, the tools for microbial community analysis are increasingly accessible, and community-based approaches have unparalleled potential for translation into rapid, perhaps real-time, monitoring platforms.
Flow distribution analysis on the cooling tube network of ITER thermal shield
Nam, Kwanwoo; Chung, Wooho; Noh, Chang Hyun; Kang, Dong Kwon; Kang, Kyoung-O; Ahn, Hee Jae; Lee, Hyeon Gon [ITER Korea, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of)
Thermal shield (TS) is to be installed between the vacuum vessel or the cryostat and the magnets in ITER tokamak to reduce the thermal radiation load to the magnets operating at 4.2K. The TS is cooled by pressurized helium gas at the inlet temperature of 80K. The cooling tube is welded on the TS panel surface and the composed flow network of the TS cooling tubes is complex. The flow rate in each panel should be matched to the thermal design value for effective radiation shielding. This paper presents one dimensional analysis on the flow distribution of cooling tube network for the ITER TS. The hydraulic cooling tube network is modeled by an electrical analogy. Only the cooling tube on the TS surface and its connecting pipe from the manifold are considered in the analysis model. Considering the frictional factor and the local loss in the cooling tube, the hydraulic resistance is expressed as a linear function with respect to mass flow rate. Sub-circuits in the TS are analyzed separately because each circuit is controlled by its own control valve independently. It is found that flow rates in some panels are insufficient compared with the design values. In order to improve the flow distribution, two kinds of design modifications are proposed. The first one is to connect the tubes of the adjacent panels. This will increase the resistance of the tube on the panel where the flow rate is excessive. The other design suggestion is that an orifice is installed at the exit of tube routing where the flow rate is to be reduced. The analysis for the design suggestions shows that the flow mal-distribution is improved significantly.
SUBMITTED TO THE INTERNATIONAL JOURNAL OF FLOW CONTROL, REVISED VERSION 1 Fluid Flow Control: a Vision-Based Approach
Paris-Sud XI, Universitķ de
SUBMITTED TO THE INTERNATIONAL JOURNAL OF FLOW CONTROL, REVISED VERSION 1 Fluid Flow Control, by visualizing a fluid flow, dense flow velocity maps can be computed via optical flow techniques by diminishing the fuel consumption of their aircrafts through drag reduction [1]. In contrast, in other
Hybrid Recursive Energy-based Method for Robust Optical Flow on Large Motion Fields
Wichmann, Felix
Hybrid Recursive Energy-based Method for Robust Optical Flow on Large Motion Fields Jangheon Kim, and convergence to the global minima is not guaranteed. Our hybrid recursive energy-based method employs, Germany {j.kim, email@example.com Abstract--We present a new reliable hybrid recursive method
An Integral Flow-Based Energy-Efficient Routing Algorithm for Wireless Sensor Networks
Prakash, Ravi
An Integral Flow-Based Energy-Efficient Routing Algorithm for Wireless Sensor Networks Shashidhar. As sensor nodes are energy-constrained, energy-efficient routing is essential for increasing the lifetime. In this paper, we consider static base stations and propose an algorithmic approach to obtain integral energy-efficient
Comparative Analysis of Natural Convection Flows Simulated by both the Conservation and Incompressible Forms of the Navier-Stokes Equations in a Differentially-Heated Square Cavity
Richard C. Martineau; Ray A. Berry; Aurķlia Esteve; Kurt D. Hamman; Dana A. Knoll; Ryosuke Park; William Taitano
This report illustrates a comparative study to analyze the physical differences between numerical simulations obtained with both the conservation and incompressible forms of the Navier-Stokes equations for natural convection flows in simple geometries. The purpose of this study is to quantify how the incompressible flow assumption (which is based upon constant density advection, divergence-free flow, and the Boussinesq gravitational body force approximation) differs from the conservation form (which only assumes that the fluid is a continuum) when solving flows driven by gravity acting upon density variations resulting from local temperature gradients. Driving this study is the common use of the incompressible flow assumption in fluid flow simulations for nuclear power applications in natural convection flows subjected to a high heat flux (large temperature differences). A series of simulations were conducted on two-dimensional, differentially-heated rectangular geometries and modeled with both hydrodynamic formulations. From these simulations, the selected characterization parameters of maximum Nusselt number, average Nusselt number, and normalized pressure reduction were calculated. Comparisons of these parameters were made with available benchmark solutions for air with the ideal gas assumption at both low and high heat fluxes. Additionally, we generated body force, velocity, and divergence of velocity distributions to provide a basis for further analysis. The simulations and analysis were then extended to include helium at the Very High Temperature gas-cooled Reactor (VHTR) normal operating conditions. Our results show that the consequences of incorporating the incompressible flow assumption in high heat flux situations may lead to unrepresentative results. The results question the use of the incompressible flow assumption for simulating fluid flow in an operating nuclear reactor, where large temperature variations are present. The results show that the use of the incompressible flow assumption with the Boussinesq gravitational body force approximation should be restricted to flows where the density change of a fluid particle along a pathline is negligible.
Study of an ammonia-based wet scrubbing process in a continuous flow system
Mao, James X.; Lee, Anita S.; Kitchin, John R.; Nulwala, Hunaid B.; Luebke, David R.; Damodaran, Krishnan
A continuous gas and liquid flow, regenerative scrubbing process for CO{sub 2} capture was demonstrated at the bench-scale level. An aqueous ammonia-based solution captures CO{sub 2} from simulated flue gas in an absorber and releases a nearly pure stream of CO{sub 2} in the regenerator. After the regeneration, the solution of ammonium compounds is recycled to the absorber. The design of a continuous flow unit was based on earlier exploratory results from a semi-batch reactor, where a CO{sub 2} and N{sub 2} simulated flue gas mixture flowed through a well-mixed batch of ammonia-based solution. During the semi-batch tests, the solution was cycled between absorption and regeneration steps to measure the carrying capacity of the solution at various initial ammonia concentrations and temperatures. Consequentially, a series of tests were conducted on the continuous unit to observe the effect of various parameters on CO{sub 2} removal efficiency and regenerator effectiveness within the flow system. The parameters that were studied included absorber temperature, regenerator temperature, initial NH{sub 3} concentration, simulated flue gas flow rate, liquid solvent inventory in the flow system, and height of the packed-bed absorber. From this testing and subsequent testing, ammonia losses from both the absorption and regeneration steps were quantified, and attempts were made to maintain steady state during operations. Implications of experimental results with respect to process design are discussed.
A Detailed Analysis of Guard-Heated Wall Shear Stress Sensors for Turbulent Flows Seyed Ali Ale Etrati Khosroshahi
Victoria, University of
A Detailed Analysis of Guard-Heated Wall Shear Stress Sensors for Turbulent Flows by Seyed Ali Ale A Detailed Analysis of Guard-Heated Wall Shear Stress Sensors for Turbulent Flows by Seyed Ali Ale Etrati-dimensional analysis of the performance of multi-element guard-heated hot-film wall shear stress microsensors
Development of a cell-based stream flow routing model
Raina, Rajeev
This study presents the development of a cell-based routing model. The model developed is a two parameter hydrological routing model that uses a coarse resolution stream network to route runoff from each cell in the watershed to the outlet...
To cite this version : Rigo-Mariani, Rmy and Sareni, Bruno and Roboam, Xavier Fast Power Flow Scheduling and Sensitivity Analysis for Sizing a
Mailhes, Corinne
dispatching of power flows in a microgrid with storage. The investigated approach is based on the use Scheduling and Sensitivity Analysis for Sizing a Microgrid with Storage. (2014) In: 11th International FOR SIZING A MICROGRID WITH STORAGE R. Rigo-Mariani1 , B. Sareni1 , X. Roboam1 1. Universitķ de Toulouse
Stability analysis of the Witten black hole (cigar soliton) under world-sheet RG flow
Carolyn Lambert; Vardarajan Suneeta
We analyze the stability of the Euclidean Witten black hole (the cigar soliton in mathematics literature) under first-order RG (Ricci) flow of the world-sheet sigma model. This analysis is from the target space point of view. We find that the Witten black hole has no unstable normalizable perturbative modes in a linearized mode analysis in which we consider circularly symmetric perturbations. Finally, we discuss a result from mathematics that implies the existence of a non-normalizable mode of the Witten black hole under which the geometry flows to the sausage solution studied by Fateev, Onofri and Zamolodchikov.
An analysis of the induced flow downstream between oscillating wings in a wind tunnel
Morgan, Barry Erwin
AN ANALYSIS OF THE INDUCED FLOW DOWNSTREAM BETWEEN OSCILLATING WINGS IN A WIND TIMBAL A Thesis by BARRY ERWIN MORGAN Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER... OF SCIENCE May 1970 Major Subject; Aerospace Engineering AN ANALYSIS OF THE INDUCED FLOW DOWNSTREAM BETWEEN OSCILLATING WINGS IN A WIND TUNNEL A Thesis by BARRY ERWIN MORGAN Approved as to style and content by: rman of Committee) (Hea of Depart ent...
Newton-Krylov Methods in Power Flow and Contingency Analysis
Vuik, Kees
for the generation, transmission, and distribution of electrical energy. Power systems are considered to be the largest and most complex man-made systems. As electrical energy is vital to our society, power systems are calculated given the generation and consumption. In contingency analysis, equipment outages are simulated
Power flow analysis for DC voltage droop controlled DC microgrids
Chaudhary, Sanjay
loss, such as photovoltaic panels, batteries, fuel cells, LEDs, and electronic loads, DC microgrids sharing and secondary voltage regulation can now be analytically studied, and specialized optimization of the DC microgrid, in term of systematic analysis, protection coordination design, network optimization
Two-phase stratified flow regime transition analysis for low gravity conditions
Miller, Kathryn M.
the effect of the gas and liquid mass flow rates, fluid properties, pipe diameter, angle of pipe inclination, and gravity. Five basic flow regimes were considered: smooth stratified, wavy stratified, intermittent (slug and plug), annular with dispersed... Numerical Solution The premise used in this work for solving for the transition boundary is based on the assumption that the transition from the stratified regime to some other regime will occur when a very small wave exists on the surface of the liquid...
Version: 6/16/98 Keywords: wavy surface flow, finite element, longwave analysis, weakly-nonlinear analysis
McCready, Mark J.
Version: 6/16/98 Keywords: wavy surface flow, finite element, longwave analysis, weakly and drag are found, from finite element calculations, to increase as amplitude to approximately the third wavelength problem is solved numerically with a finite element formulation providing qualitative trends
Non-perturbative analysis of space charge limited electron flow in critical regimes
Rokhlenko, A.; Lebowitz, J. L. [Department of Mathematics, Rutgers University, Piscataway, New Jersey 08854-8019 (United States)
The combined Eulerian-Lagrangian formalism, developed in our previous work for studying the turn on regime of a one-dimensional diode, is extended for wider versatility and better precision in the study of the time dependent space charge limited electron flow with fixed injected current. An analytical analysis is supplemented with an approximate numerical scheme which appears to be sufficiently accurate to calculate the flow evolution until the process approaches stabilization or becomes unstable. This can be compared with properties of stationary flows and showed to be in a good agreement with them. When the stabilization is impossible, the ratio of anode to cathode currents is decreasing and thus the space charge is accumulated in the diode. We discuss the limitations of our approach and give some qualitative estimates for the flow parameters when stabilization is impossible.
RETROSPECTIVE: Higher-order control-flow analysis in retrospect
Shivers, Olin
that the SSA revolution in the traditional com- piler community was essentially CPS in another guise [10 there are interesting program analyses and optimisations that require this kind of extra power. CPS as an intermediate representation based on continuation-passing style (CPS). This continued a line of work originating with Steele
Optimization Online - Convergence analysis of sampling-based ...
Vincent Guigues
Aug 19, 2014 ... Convergence analysis of sampling-based decomposition methods for risk-averse multistage stochastic convex programs.
Optimization Online - Convergence Analysis of Primal-Dual Based ...
Wenyi Tian
Sep 24, 2014 ... Convergence Analysis of Primal-Dual Based Methods for Total Variation Minimization with Finite Element Approximation.
Topological Performance Measures as Surrogates for Physical Flow Models for Risk and Vulnerability Analysis for Electric Power Systems
LaRocca, Sarah; Hassel, Henrik; Guikema, Seth
Critical infrastructure systems must be both robust and resilient in order to ensure the functioning of society. To improve the performance of such systems, we often use risk and vulnerability analysis to find and address system weaknesses. A critical component of such analyses is the ability to accurately determine the negative consequences of various types of failures in the system. Numerous mathematical and simulation models exist which can be used to this end. However, there are relatively few studies comparing the implications of using different modeling approaches in the context of comprehensive risk analysis of critical infrastructures. Thus in this paper, we suggest a classification of these models, which span from simple topologically-oriented models to advanced physical flow-based models. Here, we focus on electric power systems and present a study aimed at understanding the tradeoffs between simplicity and fidelity in models used in the context of risk analysis. Specifically, the purpose of this pa...
Single-layer planar on-chip flow cytometer using microfluidic drifting based three-dimensional (3D) hydrodynamic focusing
cytometry, this can be achieved by focusing the cell solution at the centre of the flow tube horizontal (parallel to the device plane) sheath flows. One may readily fabricate the device for 2DSingle-layer planar on-chip flow cytometer using microfluidic drifting based three-dimensional (3D
A stabilized mixed finite element method for Darcy flow based on a multiscale decomposition of the solution
Masud, Arif
. There are many processes in nat- ure that can be modeled using the Darcy flow equations. Oil extraction to be solenoidal (i.e., a divergence free vector field). The main issue is that the equations of Darcy flow leadA stabilized mixed finite element method for Darcy flow based on a multiscale decomposition
Toward compressed DMD: spectral analysis of fluid flows using sub-Nyquist-rate PIV data
Tu, Jonathan H; Kutz, J Nathan; Shang, Jessica K
Dynamic mode decomposition (DMD) is a powerful and increasingly popular tool for performing spectral analysis of fluid flows. However, it requires data that satisfy the Nyquist-Shannon sampling criterion. In many fluid flow experiments, such data are impossible to capture. We propose a new approach that combines ideas from DMD and compressed sensing. Given a vector-valued signal, we take measurements randomly in time (at a sub-Nyquist rate) and project the data onto a low-dimensional subspace. We then use compressed sensing to identify the dominant frequencies in the signal and their corresponding modes. We demonstrate this method using two examples, analyzing both an artificially constructed test dataset and particle image velocimetry data collected from the flow past a cylinder. In each case, our method correctly identifies the characteristic frequencies and oscillatory modes dominating the signal, proving the proposed method to be a capable tool for spectral analysis using sub-Nyquist-rate sampling.
Large Eddy Simulation Analysis of Flow Field Inside a High-g Combustor
Raman, Venkat
Large Eddy Simulation Analysis of Flow Field Inside a High-g Combustor C. Heye , C. Lietz , J-compact combustors (UCC) are a technology for reducing the size of combustors. In these combustors the fuel and air results exhibit significant entrainment of fuel into recirculation zones inside the combustor, however
Analysis of Pt/C electrode performance in a flowing-electrolyte alkaline fuel cell
Kenis, Paul J. A.
Analysis of Pt/C electrode performance in a flowing- electrolyte alkaline fuel cell Fikile R cell Electrode characterization X-ray micro-computed tomography Microfluidic fuel cell Carbonates a b a microfluidic H2/O2 fuel cell as an analytical platform. Both anodes and cathodes were investigated
A perturbation analysis of the unstable plastic flow pattern evolution in an aluminum alloy
Tong, Wei
A perturbation analysis of the unstable plastic flow pattern evolution in an aluminum alloy Seung Abstract In the tensile loading of sheet metals made from some polycrystalline aluminum alloys, a single in the uniaxial tension of polycrystalline aluminum alloys with periodic stress relaxations depends
Continuous Flow Analysis of Total Organic Carbon in Polar Ice Cores
Stocker, Thomas
Continuous Flow Analysis of Total Organic Carbon in Polar Ice Cores U R S F E D E R E R , * , , P, University of Bern, Bern, Switzerland, Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland, and British Antarctic Survey, Cambridge, United Kingdom Received May 6, 2008. Revised manuscript
Flow analysis and nozzle-shape optimization for the cold-gas dynamic-spray process
Grujicic, Mica
Flow analysis and nozzle-shape optimization for the cold-gas dynamic-spray process M Grujicic1*, W, maximizes the acceleration of the particles. Furthermore, it is found that if the cold-spray nozzle, a significant increase in the average velocity of the particles at the nozzle exit can be obtained
Two-phase refrigerant flow instability analysis and active control in transient electronics cooling systems
Peles, Yoav
Two-phase refrigerant flow instability analysis and active control in transient electronics cooling Pressure-drop oscillation Refrigeration system Two-phase cooling Active control Transient heat load a b s t r a c t Two-loop refrigeration systems are being explored for two-phase cooling of ultra high power
Rheo-PIV Analysis of the Yielding and Flow of Model Waxy Crude Oils
Rheo-PIV Analysis of the Yielding and Flow of Model Waxy Crude Oils Christopher J. email@example.com Abstract Waxes are a commonly encountered precipitate that can result in gelation of crude oils behavior similar to waxy crude oils encountered in production scenarios. To study the consequences
Analysis of granular flow in a pebble-bed nuclear reactor Chris H. Rycroft,1
Bazant, Martin Z.
Analysis of granular flow in a pebble-bed nuclear reactor Chris H. Rycroft,1 Gary S. Grest,2 James February 2006; published 24 August 2006 Pebble-bed nuclear reactor technology, which is currently being States, the Modular Pebble Bed Reactor MPBR 4,8 is a candidate for the next generation nuclear plant
Randomized flow model and centrality measure for electrical power transmission network analysis
Boyer, Edmond
the vulnerability of electric power infrastructure systems [2, 3]. The focus of these types of studies is typically1 Randomized flow model and centrality measure for electrical power transmission network analysis. Centrality measures can then be coherently defined. An example of application to an electrical power
Power Flow Analysis Algorithm for Islanded LV Microgrids Including Distributed Generator Units with
Chaudhary, Sanjay
Power Flow Analysis Algorithm for Islanded LV Microgrids Including Distributed Generator Units With larger portion of growing electricity demand which is being fed through distributed generation (DG power system. Being able to operate in both grid-connected and islanded mode, a microgrid manages
A Genetic Algorithm based Approach for Multi-Objective Data-Flow Graph Optimization
Coello, Carlos A. Coello
that the correct- ness of algebraic transformations realized by the underlying genetic operators selection shown for power optimization. In order to avoid inferior results caused by the counteracting demandsA Genetic Algorithm based Approach for Multi-Objective Data-Flow Graph Optimization Birger Landwehr
Adaptation of Organizational Models for Multi-Agent Systems based on Max Flow Networks
L¾pez-Sßnchez, Maite
Adaptation of Organizational Models for Multi-Agent Systems based on Max Flow Networks Mark Amsterdam, The Netherlands firstname.lastname@example.com http://www.cs.vu.nl/~mhoogen Abstract Organizational models of the organizational model can be essential to ensure a continuous success- ful function of the system. This paper
Coupling concept based on thermodynamic equilibrium using the mortar method: Stokes equation (free-flow region)
Cirpka, Olaf Arie
-flow region): Mass balance (porous medium, given by Darcy`s law): Transport equation, Lagrange multiplierCoupling concept based on thermodynamic equilibrium using the mortar method: Stokes equation (free-Laplace equation is used to determine which tubes are filled with water: Coupling concept for the one-phase micro
Chappell, Nick A
that catchment or even slope scale simulation using parameters of the Darcy-Buckingham-Richards equation, the validity of the Richards equation (or the Darcy- Buckingham equation in its steady-state form) at slopeTRACER AND DARCY-BASED IDENTIFICATION OF SUBSURFACE FLOW, BUKIT TIMAH FOREST, SINGAPORE M
A FIRST ORDER PROJECTION-BASED TIME-SPLITTING SCHEME FOR COMPUTING CHEMICALLY REACTING FLOWS, surface catalytic reactors for methane to methanol conversion and chemical vapor deposition (CVD) process ANDREAS PROHL1 Abstract. The simulation of chemically reacting ows in speci#12;c situations is a basic
VISION-BASED CONTROL OF 2D PLANE POISEUILLE FLOW Romeo Tatsambon Fomena and Christophe Collewet
Paris-Sud XI, Universitķ de
Cemagref, INRIA Rennes-Bretagne Atlantique and Universit┤e Europ┤eenne de Bretagne 17 avenue de Cucill in optimizing shapes or in choosing suitable surfacing. Conversely, in active con- trol an external energy the vision-based control approach to regulate the 2D plane Poiseuille flow around its steady state
Physics-Based Low Order Galerkin Models in Fluid Dynamics & Flow Control
Gorban, Alexander N.
(Berlin Institute of Technology MB1, Germany) Marek Morzynski (Poznan University of Technology, Poland models of energy supply and consumption. Yet a third principle is the realization that governing flow to time-averaged energy dynamics of Galerkin modes, and gives rise to physically based, nonlinear sub
A Coupled Approach for Plasma-Based Flow Control Simulations of Wing Sections
Roy, Subrata
a role in momentum coupling, though as noted in Ref. 10 there is no significant heating of the airA Coupled Approach for Plasma-Based Flow Control Simulations of Wing Sections Datta V. Gaitonde Vehicles Directorate Kettering University Air Force Research Laboratory Flint, MI 48504 Wright
Level Set Based Simulations of Two-Phase Oil-Water Flows in Pipes
Soatto, Stefano
the assumption that the densities of the two uids are di#11;erent and that the viscosity of the oil core is veryLevel Set Based Simulations of Two-Phase Oil-Water Flows in Pipes Hyeseon Shim July 31, 2000 Abstract We simulate the axisymmetric pipeline transportation of oil and water numerically under
John Gardner; Kevin Heglund; Kevin Van Den Wymelenberg; Craig Rieger
It is widely understood that energy storage is the key to integrating variable generators into the grid. It has been proposed that the thermal mass of buildings could be used as a distributed energy storage solution and several researchers are making headway in this problem. However, the inability to easily determine the magnitude of the buildingÆs effective thermal mass, and how the heating ventilation and air conditioning (HVAC) system exchanges thermal energy with it, is a significant challenge to designing systems which utilize this storage mechanism. In this paper we adapt modal analysis methods used in mechanical structures to identify the primary modes of energy transfer among thermal masses in a building. The paper describes the technique using data from an idealized building model. The approach is successfully applied to actual temperature data from a commercial building in downtown Boise, Idaho.
1992 Columbia River Salmon Flow Measures Options Analysis/EIS : Appendices.
Not Available
This Options Analysis/Environmental Impact Statement (OA/EIS) identifies, presents effects of, and evaluates the potential options for changing instream flow levels in efforts to increase salmon populations in the lower Columbia and Snake rivers. The potential actions would be implemented during 1992 to benefit juvenile and adult salmon during migration through eight run-of-river reservoirs. The Corps of Engineers (Corps) prepared this document in cooperation with the Bonneville Power Administration and the Bureau of Reclamation. The US Fish and Wildlife Service (FWS) is a participating agency. The text and appendices of the document describe the characteristics of 10 Federal projects and one private water development project in the Columbia River drainage basin. Present and potential operation of these projects and their effects on the salmon that spawn and rear in the Columbia and Snake River System are presented. The life history, status, and response of Pacific salmon to current environmental conditions are described. The document concludes with an evaluation of the potential effects that could result from implementing proposed actions. The conclusions are based on evaluation of existing data, utilization of numerical models, and application of logical inference. This volume contains the appendices.
Dependence-Based Program Analysis Richard Johnson
Pingali, Keshav K.
information 1This research was supported by an NSF Presidential Young Investigator award CCR-8958543, NSF to these prob- lems. They permit informationto flow directly between defi- nitions and uses without going
Demonstration of a plasma mirror based on a laminar flow water film
Panasenko, Dmitriy; Shu, Anthony; Gonsalves, Anthony; Nakamura, Kei; Matlis, Nicholas; Toth, Csaba; Leemans, Wim
A plasma mirror based on a laminar water film with low flow speed 0.5-2 cm/s has been developed and characterized, for use as an ultrahigh intensity optical reflector. The use of flowing water as atarget surface automatically results in each laser pulse seeing a new interaction surface and avoids the need for mechanical scanning of the target surface. In addition, the breakdown of water does notproduce contaminating debris that can be deleterious to vacuum chamber conditions and optics, such as is the case when using conventional solid targets. The mirror exhibits 70percent reflectivity, whilemaintaining high-quality of the reflected spot.
Feature-based Analysis of Plasma-based Particle Acceleration Data
Feature-based Analysis of Plasma-based Particle Acceleration Data Oliver R³bel 1 , Cameron G;1 Feature-based Analysis of Plasma-based Particle Acceleration Data Oliver R©ubel, Cameron G.R. Geddes, Min Chen, Estelle Cormier-Michel, and E. Wes Bethel Abstract Plasma-based particle accelerators can produce
Bismuth-based electrochemical stripping analysis
Wang, Joseph
Method and apparatus for trace metal detection and analysis using bismuth-coated electrodes and electrochemical stripping analysis. Both anodic stripping voltammetry and adsorptive stripping analysis may be employed.
Analysis of Compressible and Incompressible Flows Through See-through Labyrinth Seals
Woo, Jeng Won
of the working fluid through the labyrinth seal is desirable because it improves the efficiency of the turbomachine. The carry-over coefficient, based on the divergence angle of the jet, changed with flow parameters with fixed seal geometry while earlier models...
Geographically-Based Infrastructure Analysis | Department of...
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Infrastructure Analysis given by Keith Parks of the National Renewable Energy Laboratory during the DOE Hydrogen Transition Analysis Workshop on January 26,...
The backward phase flow and FBI-transform-based Eulerian Gaussian beams for the Schroedinger equation
Leung Shingyu, E-mail: firstname.lastname@example.com [Department of Mathematics, Hong Kong University of Science and Technology, Clear Water Bay (Hong Kong); Qian Jianliang, E-mail: email@example.com [Department of Mathematics, Michigan State University, East Lansing, MI 48824 (United States)
We propose the backward phase flow method to implement the Fourier-Bros-Iagolnitzer (FBI)-transform-based Eulerian Gaussian beam method for solving the Schroedinger equation in the semi-classical regime. The idea of Eulerian Gaussian beams has been first proposed in . In this paper we aim at two crucial computational issues of the Eulerian Gaussian beam method: how to carry out long-time beam propagation and how to compute beam ingredients rapidly in phase space. By virtue of the FBI transform, we address the first issue by introducing the reinitialization strategy into the Eulerian Gaussian beam framework. Essentially we reinitialize beam propagation by applying the FBI transform to wavefields at intermediate time steps when the beams become too wide. To address the second issue, inspired by the original phase flow method, we propose the backward phase flow method which allows us to compute beam ingredients rapidly. Numerical examples demonstrate the efficiency and accuracy of the proposed algorithms.
Ring diagram analysis of near-surface flows in the Sun
Sarbani Basu; H. M. Antia; S. C. Tripathy
Ring diagram analysis of solar oscillation power spectra obtained from MDI data is carried out to study the velocity fields in the outer part of the solar convection zone. The three dimensional power spectra are fitted to a model which has a Lorentzian profile in frequency and which includes the advection of the wave front by horizontal flows, to obtain the two components of the sub-surface flows as a function of the horizontal wave number and radial order of the oscillation modes. This information is then inverted using OLA and RLS methods to infer the variation in horizontal flow velocity with depth. The average rotation velocity at different latitudes obtained by this technique agrees reasonably with helioseismic estimates made using frequency splitting data. The shear layer just below the solar surface appears to consist of two parts with the outer part up to a depth of 4 Mm, where the velocity gradient does not show any reversal up to a latitude of 60 degrees. In the deeper part the velocity gradient shows reversal in sign around a latitude of 55 degrees. The zonal flow velocities inferred in the outermost layers appears to be similar to those obtained by other measurements. A meridional flow from equator polewards is found. It has a maximum amplitude of about 30 m/s near the surface and the amplitude is nearly constant in the outer shear layer.
Asset-based poverty analysis in rural Bangladesh: A comparison of principal component analysis and
Mound, Jon
1 Asset-based poverty analysis in rural Bangladesh: A comparison of principal component analysis not be regarded as the views of SRI or The University of Leeds. #12;3 Asset-based poverty analysis in rural The trend towards multi-dimensional poverty assessment ..................... 5 Principal component analysis
Analysis of Energy Efficiency Program Impacts Based on Program...
U.S. Energy Information Administration (EIA) Indexed Site
Analysis of Energy Efficiency Program Impacts Based on Program Spending May 2015 Independent Statistics & Analysis www.eia.gov U.S. Department of Energy Washington, DC 20585 U.S....
Cloud-Based Statistical Analysis from Users' Perspective Botong Huang
Yang, Jun
efficient statistical analysis programs requires tremendous expertise and effort. Most statisticians would much prefer programming in languages familiar to them, such as R and MATLAB, Copyright 2014 IEEECumulon: Cloud-Based Statistical Analysis from Users' Perspective Botong Huang Department
Agent-Based Modeling and Simulation for Hydrogen Transition Analysis
Broader source: Energy.gov [DOE]
Presentation on Agent-Based Modeling and Simulation for Hydrogen Transition Analysis given by Marianne Mintz of ANL during the DOE Hydrogen Transition Analysis Workshop on January 26, 2006.
A comparison of an analytical and two electric analogy methods of hydraulic flow analysisĀ
Hoffman, Joe Douglas
~ THE LINEAR RESISTANCE EIKCTRIC ANAIOGY METHOD . . . . . . 57 IX ~ THE NON-LINEAR RESISTANCE ELECTRIC ANALOGY METHOD, . 75 Xo DISCUSSION OF RESULTS XIo CONCLUSIONS APPENDIX BIBLIOGRAPHY 95 101 104 109 I, INTRODUCTION Although networks of hydraulic... pipelines are used throughout the world, the analysis of their steady state performance is a difficult and time consuming process . The work involved in ana- lysing a network of pipelines to determine flow rates and energy losses throughout the network...
Local analysis of three-dimensional air cooled condenser using a two-phase flow diagram
Parise, J.A.R.; Cartwright
This paper is concerned with the development and application of an analytical method for the performance prediction of air cooled condensers. A local analysis is employed in which the condenser is considered as a matrix of small basic heat transfer modules. For each element, local film coefficients for both the air and the condensing fluid are determined according to the existing local conditions, including the two-phase flow regime. The paper considers an application of the method to heat pump condensing.
An analysis of the standard system of differential equations describing multi-speed flows of multi-phase media is performed. It is proved that the Cauchy problem, as posed in most best-estimate thermal-hydraulic codes, results in unstable solutions and potentially unreliable description of many physical phenomena. A system of equations, free from instability effects, is developed allowing more rigorous numerical modeling.
Statistical Analysis of Microgravity Two-Phase Slug Flow via the Drift Flux Model
Larsen, Benjamin A
STATISTICAL ANALYSIS OF MICROGRAVITY TWO-PHASE SLUG FLOW VIA THE DRIFT FLUX MODEL A Thesis by BENJAMIN ANDREW LARSEN Submitted to the Office of Graduate and Professional Studies of Texas A&M University in partial fulfillment... made their data available to me and willingly took the time to converse about their work. Finally I would like to thank my parents Donald and Christine Larsen for their love and support in completing my graduate work. v NOMENCLATURE Symbol...
analysis based control: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Ping Yang; Scott D. Stoller; C. R. Ramakrishnan 2006-01-01 8 FAULT TOLERANT CONTROL SYSTEM DESIGN: A RECONFIGURATIN STRATEGY BASED ON RELIABILITY ANALYSIS UNDER DYNAMIC BEHAVIOR...
NETL - Petroleum-Based Fuels Life Cycle Greenhouse Gas Analysis...
Tool Summary LAUNCH TOOL Name: NETL - Petroleum-Based Fuels Life Cycle Greenhouse Gas Analysis 2005 Baseline Model AgencyCompany Organization: National Energy Technology...
analysis tool based: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Visualization Requirements, Implementation Future Work 12 Weidendorfer, Josef 2 Web-based pre-Analysis Tools CERN Preprints Summary: The project consists in the initial...
Performance Analysis of Accumulator-based Revocation Mechanisms
Boyer, Edmond
Performance Analysis of Accumulator-based Revocation Mechanisms Jorn Lapon1, Markulf Kohlweiss3 issues is the efficient revocation of anonymous credentials. Currently, accumulator based re- vocation- cations. Keywords: Anonymous Credentials, Revocation, Accumulators 1 Introduction In an increasing
Surface-Based Analysis of Functional Magnetic Resonance Imaging Data
Thompson, Paul
Surface-Based Analysis of Functional Magnetic Resonance Imaging Data Theo G.M. van Erp1, Vikas Y School of Medicine, Los Angeles, CA 90095, USA Abstract. Surface-based visualization, atlases the integration of surface-based tech- niques with functional imaging data, combining surface-based nonlinear
Boyer, Edmond
EXPERIMENTAL AND NUMERICAL ANALYSIS OF THE FLOW INSIDE A CONFIGURATION INCLUDING AN AXIAL PUMP-30723) In centrifugal and axial pumps, the flow is characterized by a turbulent and complex behavior and also of a configuration that includes an axial pump and a bundle of tubes that mimics the cool source of a heat exchanger
Convex-Based Thermal Management for 3D MPSoCs Using DVFS and Variable-Flow Liquid Cooling
De Micheli, Giovanni
management using variable-flow liquid cooling. 1 Introduction Power and thermal management are important] is a thermal model tool that calculates transient temperature response given the physical and power consumptionConvex-Based Thermal Management for 3D MPSoCs Using DVFS and Variable-Flow Liquid Cooling Francesco
Jitter-based analysis and discussion of burst assembly algorithms
Aracil, Javier
Jitter-based analysis and discussion of burst assembly algorithms Javier Aracil, Jos┤e Alberto Hern a jitter analysis of size-based burst assembly algorithms and also discusses other burst assem- bly algorithms that use the packet delay as the assembly threshold to provide a bound on jitter. Index Terms
SUMMARY-BASED POINTER ANALYSIS FRAMEWORK FOR MODULAR BUG FINDING Marcio O. Buss Submitted of Arts and Sciences COLUMBIA UNIVERSITY 2007 #12;c 2007 Marcio O. Buss All Rights Reserved #12;ABSTRACT SUMMARY-BASED POINTER ANALYSIS FRAMEWORK FOR MODULAR BUG FINDING Marcio O. Buss Modern society
Model Structure Analysis for Model-based Operation of
Van den Hof, Paul
conducted in the framework of the "Integrated System Approach Petroleum Production" (ISAPP) programmeModel Structure Analysis for Model-based Operation of Petroleum Reservoirs #12;#12;MODEL STRUCTURE ANALYSIS FOR MODEL-BASED OPERATION OF PETROLEUM RESERVOIRS PROEFSCHRIFT ter verkrijging van de graad van
Time-resolved fuel injector flow characterisation based on 3D laser Doppler vibrometry
Crua, Cyril
In order to enable investigations of the fuel flow inside unmodified injectors, we have developed a new experimental approach to measure time-resolved vibration spectra of diesel nozzles using a three dimensional laser vibrometer. The technique we propose is based on the triangulation of the vibrometer and fuel pressure transducer signals, and enables the quantitative characterisation of quasi-cyclic internal flows without requiring modifications to the injector, the working fluid, or limiting the fuel injection pressure. The vibrometer, which uses the Doppler effect to measure the velocity of a vibrating object, was used to scan injector nozzle tips during the injection event. The data were processed using a discrete Fourier transform to provide time-resolved spectra for valve-closed-orifice, minisac and microsac nozzle geometries, and injection pressures ranging from 60 to 160MPa, hence offering unprecedented insight into cyclic cavitation and internal mechanical dynamic processes. A peak was consistently f...
Medially Based Meshing with Finite Element Analysis of Prostate Deformation
Crouch, Jessica R.
Medially Based Meshing with Finite Element Analysis of Prostate Deformation Jessica R. Crouch1 have approached prostate imaging problems using meth- ods that incorporate finite element analysis. Assume the prostate is a linearly elastic body and compute its deformation using finite element analysis
Analysis of the Loss of Forced Reactor Coolant Flow Accident in SMART using RETRAN-03/INT
Kim, Tae-Wan; Suh, Kune-Yull; Lee, Un-Chul; Park, Goon-Cherl [Department of Nuclear Engineering, Seoul National University, San 56-1, Shinlim-dong, Kwanak-gu, Seoul 151-742 (Korea, Republic of); Kim, Jae-Hak [Future and Challenge Co., LTD., 130-202, San 56-1, Shinlim-dong, Kwanak-gu, Seoul 151-742 (Korea, Republic of)
Small and medium integral type nuclear reactors are getting much attention for the peaceful use of nuclear energy in non-electric area such as district heating, seawater desalination and ship propulsion. An integral type nuclear co-generation reactor, SMART(System-integrated Modular Advanced ReacTor, 330 MWt), has been developed by KAERI (Korea Atomic Energy Research Institute) since 1996. In this study, the safety analysis for SMART using modified RETRAN-03 code whose name is RETRAN-03/INT is performed to examine the applicability of RETRAN-03/INT code. For the safety analysis of integral reactor with helical-coiled steam generators, RETRAN-03 code has been modified and verified using experimental results. New heat transfer coefficients are added for helical-coiled steam generator. And, the heat transfer model for steam generator is modified due to the different primary and secondary side heat flow from U-tube type steam generator. The loss of forced reactor coolant flow accident is selected for safety analysis in this study. Also it is considered as a single failure that one of three trains of passive residual heat removal system is failed. The results from MARS/SMR code and RETRAN-03/INT code are compared. (authors)
Thickness-based adaptive mesh refinement methods for multi-phase flow simulations with thin regions
Chen, Xiaodong [The State Key Laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190 (China); Yang, Vigor, E-mail: email@example.com [School of Aerospace Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0150 (United States)
In numerical simulations of multi-scale, multi-phase flows, grid refinement is required to resolve regions with small scales. A notable example is liquid-jet atomization and subsequent droplet dynamics. It is essential to characterize the detailed flow physics with variable length scales with high fidelity, in order to elucidate the underlying mechanisms. In this paper, two thickness-based mesh refinement schemes are developed based on distance- and topology-oriented criteria for thin regions with confining wall/plane of symmetry and in any situation, respectively. Both techniques are implemented in a general framework with a volume-of-fluid formulation and an adaptive-mesh-refinement capability. The distance-oriented technique compares against a critical value, the ratio of an interfacial cell size to the distance between the mass center of the cell and a reference plane. The topology-oriented technique is developed from digital topology theories to handle more general conditions. The requirement for interfacial mesh refinement can be detected swiftly, without the need of thickness information, equation solving, variable averaging or mesh repairing. The mesh refinement level increases smoothly on demand in thin regions. The schemes have been verified and validated against several benchmark cases to demonstrate their effectiveness and robustness. These include the dynamics of colliding droplets, droplet motions in a microchannel, and atomization of liquid impinging jets. Overall, the thickness-based refinement technique provides highly adaptive meshes for problems with thin regions in an efficient and fully automatic manner.
Stress-induced patterns in ion-irradiated Silicon: a model based on anisotropic plastic flow
Scott A. Norris
We present a model for the effect of stress on thin amorphous films that develop atop ion-irradiated silicon, based on the mechanism of ion-induced anisotropic plastic flow. Using only parameters directly measured or known to high accuracy, the model exhibits remarkably good agreement with the wavelengths of experimentally-observed patterns, and agrees qualitatively with limited data on ripple propagation speed. The predictions of the model are discussed in the context of other mechanisms recently theorized to explain the wavelengths, including extensive comparison with an alternate model of stress.
Analysis of Mass Flow and Enhanced Mass Flow Methods of Flashing Refrigerant-22 from a Small Vessel
Nutter, Darin Wayne
The mass flow characteristics of flashing Refrigerant-22 from a small vessel were investigated. A flash boiling apparatus was designed and built. It was modeled after the flashing process encountered by the accumulator of air-source heat pump...
Linear analysis of time dependent properties of Child-Langmuir flow
Rokhlenko, A. [Department of Mathematics, Rutgers University, Piscataway, New Jersey 08854-8019 (United States)
We continue our analysis of the time dependent behavior of the electron flow in the Child-Langmuir system, removing an approximation used earlier. We find a modified set of oscillatory decaying modes with frequencies of the same order as the inverse of the electron transient time. This range (typically MHz) allows simple experimental detection and maybe exploitation. We then study the time evolution of the current in response to a slow change of the anode voltage where the same modes of oscillations appear too. The cathode current in this case is systematically advanced or retarded depending on the direction of the voltage change.
Uncertainty Analysis Framework - Hanford Site-Wide Groundwater Flow and Transport Model
Cole, Charles R.; Bergeron, Marcel P.; Murray, Christopher J.; Thorne, Paul D.; Wurstner, Signe K.; Rogers, Phillip M.
Pacific Northwest National Laboratory (PNNL) embarked on a new initiative to strengthen the technical defensibility of the predictions being made with a site-wide groundwater flow and transport model at the U.S. Department of Energy Hanford Site in southeastern Washington State. In FY 2000, the focus of the initiative was on the characterization of major uncertainties in the current conceptual model that would affect model predictions. The long-term goals of the initiative are the development and implementation of an uncertainty estimation methodology in future assessments and analyses using the site-wide model. This report focuses on the development and implementation of an uncertainty analysis framework.
Value based analysis of acquisition portfolios
Burgess, Cheri Nicole Markt
Currently, program-funding allocation is based on program performance. Funding cuts commonly lead to a poor reflection on the program management assigned to the given program. If additional factors such as program risk and ...
Finite element analysis and computed tomography based structural rigidity analysis of rat tibia with simulated lytic defects
Vaziri, Ashkan
Finite element analysis and computed tomography based structural rigidity analysis of rat tibia) (Damron et al., 2003; Mirels, 1989). In contrast, Computed Tomography based Structural Rigidly Ana- lysis
Bead-Based Assays for Biodetection: From Flow-Cytometry to Microfluidics
Ozanich, Richard M.; Antolick, Kathryn C.; Bruckner-Lea, Cindy J.; Bunch, Kyle J.; Dockendorff, Brian P.; Grate, Jay W.; Nash, Michael A.; Tyler, Abby J.
ABSTRACT The potential for the use of biological agents by terrorists is a real threat. Two approaches for detection of biological species will be described: 1) The use of microbead arrays for multiplexed flow cytometry detection of cytokines and botulinum neurotoxin simulant, and 2) a microfluidic platform for capture and separation of different size superparamagnetic nanoparticles followed by on-chip fluorescence detection of the sandwich complex. The methods and automated fluidic systems used for trapping functionalized microbeads will be described. This approach allows sample, assay reagents, and wash solutions to be perfused over a micro-column of beads, resulting in faster and more sensitive assays. The automated fluidic approach resulted in up to five-fold improvements in assay sensitivity/speed as compared to identical assays performed in a typical manual batch mode. A second approach for implementing multiplexed bead-based assays without using flow cytometry detection is currently under development. The goal of the microfluidic-based approach is to achieve rapid (<20 minutes), multiplexed (> 3 bioagents) detection using a simple and low-cost, integrated microfluidic/optical detection platform. Using fiber-optic guided laser-induced fluorescence, assay detection limits were shown to be in the 100Æs of picomolar range (10Æs of micrograms per liter) for botulinum neurotoxin simulant without any optimization of the microfluidic device or optical detection approach. Video taping magnetic nanoparticle capture and release was used to improve understanding of the process and revealed interesting behavior.
Comparative analysis of plant oil based fuels
Ziejewski, M.; Goettler, H.J.; Haines, H.; Huong, C.
This paper presents the evaluation results from the analysis of different blends of fuels using the 13-mode standard SAE testing method. Six high oleic safflower oil blends, six ester blends, six high oleic sunflower oil blends, and six sunflower oil blends were used in this portion of the investigation. Additionally, the results from the repeated 13-mode tests for all the 25/75% mixtures with a complete diesel fuel test before and after each alternative fuel are presented.
Drag Reduction Study by Wavelet Analysis of Differential Pressure Signals in Turbulent Flow
Ling Zhen; Yassin, A. Hassan; Dominguez-Ontiveros, Elvis [Nuclear Engineering Department, Texas A and M University, College Station, Texas 77843 (United States)
Drag reduction was studied when micro-bubbles with low void fractions were injected in the boundary layer of a turbulent channel flow. The particle tracking velocimetry (PIV) flow measurement technique was used to measure two-dimensional full velocity fields. Since pressure field distribution is associated with turbulence behavior and dissipation, it is important to study the changes of the pressure field. However, the differential pressure signals are difficult to analyze due to irregularity. The characteristics of these signals have been studied by traditional statistical methods. In this study, the multi-resolution technique of wavelet transform based on localized wavelet functions is utilized to nonlinear pressure signals. By using continuous wavelet transform method, the pressure signals in the turbulent flow can be decomposed into its approximations and details at different resolutions. The magnitudes of the coefficients represent the energy distribution at different scales and this also can facilitate the visual observation of the energy transition process. The wavelet decomposition coefficients at different scales plot would provide a tool to further our understanding of drag reduction mechanism via micro-bubbles injection. (authors)
Development of a Water Based, Critical Flow, Non-Vapor Compression cooling Cycle
Hosni, Mohammad H.
Expansion of a high-pressure liquid refrigerant through the use of a thermostatic expansion valve or other device is commonplace in vapor-compression cycles to regulate the quality and flow rate of the refrigerant entering the evaporator. In vapor-compression systems, as the condensed refrigerant undergoes this expansion, its pressure and temperature drop, and part of the liquid evaporates. We (researchers at Kansas State University) are developing a cooling cycle that instead pumps a high-pressure refrigerant through a supersonic converging-diverging nozzle. As the liquid refrigerant passes through the nozzle, its velocity reaches supersonic (or critical-flow) conditions, substantially decreasing the refrigerantÆs pressure. This sharp pressure change vaporizes some of the refrigerant and absorbs heat from the surrounding conditions during this phase change. Due to the design of the nozzle, a shockwave trips the supersonic two-phase refrigerant back to the starting conditions, condensing the remaining vapor. The critical-flow refrigeration cycle would provide space cooling, similar to a chiller, by running a secondary fluid such as water or glycol over one or more nozzles. Rather than utilizing a compressor to raise the pressure of the refrigerant, as in a vapor-cycle system, the critical-flow cycle utilizes a high-pressure pump to drive refrigerant liquid through the cooling cycle. Additionally, the design of the nozzle can be tailored for a given refrigerant, such that environmentally benign substances can act as the working fluid. This refrigeration cycle is still in early-stage development with prototype development several years away. The complex multi-phase flow at supersonic conditions presents numerous challenges to fully understanding and modeling the cycle. With the support of DOE and venture-capital investors, initial research was conducted at PAX Streamline, and later, at Caitin. We (researchers at Kansas State University) have continued development of the cycle and have gained an in-depth understanding of the governing fundamental knowledge, based on the laws of physics and thermodynamics and verified with our testing results. Through this research, we are identifying optimal working fluid and operating conditions to eventually demonstrate the core technology for space cooling or other applications.
A Markov Decision Process based Flow Assignment Framework for Heterogeneous Network Access
Alpcan, Tansu
Engineering, Stanford University, Stanford, CA 94305, USA Varun Sharma Lehman Brothers Inc., India Abstract an optimal policy for allocation of flows to different networks. The optimal policy maximizes, under of the flow utilities. The flow assignment policy is periodically updated and is consulted by the flows
Analysis of Percussion Grip for Physically Based Character Animation
Paris-Sud XI, Universitķ de
. Firstly, it provides realistic exam- ples of the human motion under study for driving the virtualAnalysis of Percussion Grip for Physically Based Character Animation Alexandre Bou©enard* Marcelo This paper presents the analysis of percussion tech- nique for the simulation of virtual timpani playing sit
TREAT experimental data base regarding fuel dispersals in LMFBR loss-of-flow accidents
Simms, R.; Fink, C.L.; Stanford, G.S.; Regis, J.P.
The reactivity feedback from fuel relocation is a central issue in the analysis of loss-of-flow (LOF) accidents in LMFBRs. Fuel relocation has been studied in a number of LOF simulations in the TREAT reactor. In this paper the results of these tests are analyzed, using, as the principal figure of merit, the changes in equivalent fuel worth associated with the fuel motion. The equivalent fuel worth was calculated from the measured axial fuel distributions by weighting the data with a typical LMFBR fuel-worth function. At nominal power, the initial fuel relocation resulted in increases in equivalent fuel worth. Above nominal power the fuel motion was dispersive, but the dispersive driving forces could not unequivocally be identified from the experimental data.
A comparison of analog methods in heat flow analysis with simplified mathematica methods as applied to flight structures
Murray, William
in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE January 1960 Maj or Subj ect: Mechanical Engineering A COMPARISON OF ANALOG METHODS IN HEAT FLOW ANALYSIS WITH SIMPLIFIED MATHEMATICAL METHODS AS APPLIED TO FLIGHT STRUCTURES... and require lengthy and sometimes difficult mathematical computations to arrive at a solution. It is obvious that there is a need for a simple, rapid, and reliable method of solving complex problems involving heat flow. It is the purpose...
Fuel Cell System Improvement for Model-Based Diagnosis Analysis
Paris-Sud XI, Universitķ de
Fuel Cell System Improvement for Model-Based Diagnosis Analysis Philippe Fiani & Michel Batteux of a model of a fuel cell system, in order to make it usable for model- based diagnosis methods. A fuel cell for the fuel cell stack but also for the system environment. In this paper, we present an adapted library which
Analysis and Model-Based Control of Servomechanisms With Friction
Papadopoulos, Evangelos
Analysis and Model-Based Control of Servomechanisms With Friction Evangelos G. Papadopoulos e Engineering, National Technical University of Athens, 15780 Athens, Greece Friction is responsible for several, model-based feedback compensation is studied for servomechanism tracking tasks. Several kinetic friction
Patent Citation Analysis: Calculating Science linkage based on Citing Motivation
Menczer, Filippo
1 Patent Citation Analysis: Calculating Science linkage based on Citing Motivation Rui Li used patent bibliometric indicator to measure patent linkage to scientific research based on the frequency of citations to scientific papers within the patent. Science linkage is also regarded as noisy
Speeding Up SMT-Based Quantitative Program Analysis
Seshia, Sanjit A.
Speeding Up SMT-Based Quantitative Program Analysis Daniel J. Fremont and Sanjit A. Seshia-free program. These problems can be solved using a combi- nation of path enumeration, SMT solving, and model present a formalization and satisfiability modulo theories (SMT) based solution to a family
Kinetic analysis of 18F-fluorodihydrorotenone as a deposited myocardial flow tracer: Comparison to thallium-201.
Marshall, Robert C.; Powers-Risius, Patricia; Reutter, Bryan W.; O'Neil, James P.; La Belle, Michael; Huesman, Ronald H.; VanBrocklin, Henry F.
The goal of this investigation was to assess the accuracy of 18F-fluorodihydrorotenone (18F-FDHR) as a new deposited myocardial flow tracer and compare the results to those for 201Tl. Methods. The kinetics of these flow tracers were evaluated in 22 isolated, erythrocyte- and albumin-perfused rabbit hearts over a flow range encountered in patients. The two flow tracers plus a vascular reference tracer (131I-albumin) were introduced as a bolus through a port just above the aortic cannula. Myocardial extraction, retention, washout, and uptake parameters were computed from the venous outflow curves using the multiple indicator dilution technique and spectral analysis. Results. The mean initial extraction fractions of 18F-FDHR (0.85 +- 0.07) and 201Tl (0.87 +- 0.05) were not significantly different, although the initial extraction fraction for 18F-FDHR declined with flow (P < 0.0001), whereas the initial extraction fraction of 201Tl did not. Washout of 201Tl was faster (P < 0.001) and more affected by flow (P < 0.05) than 18F-FDHR washout. Except for initial extraction fraction, 18F-FDHR retention was greater (P < 0.001) and less affected by flow (P < 0.05) than 201Tl retention. Reflecting its superior retention, net uptake of 18F-FDHR was better correlated with flow than 201Tl uptake at both one and fifteen minutes after tracer introduction (P < 0.0001 for both comparisons). Conclusion. The superior correlation of 18F-FDHR uptake with flow indicates that it is a better flow tracer than 201Tl in the isolated rabbit heart. Compared to the other currently available positron-emitting flow tracers (82Rb, 13N-ammonia, and 15O-water), 18F-FDHR has the potential of providing excellent image resolution without the need for an on-site cyclotron.
Exploring Vector Fields with Distribution-based Streamline Analysis
Lu, Kewei; Chaudhuri, Abon; Lee, Teng-Yok; Shen, Han-Wei; Wong, Pak C.
Streamline-based techniques are designed based on the idea that properties of streamlines are indicative of features in the underlying field. In this paper, we show that statistical distributions of measurements along the trajectory of a streamline can be used as a robust and effective descriptor to measure the similarity between streamlines. With the distribution-based approach, we present a framework for interactive exploration of 3D vector fields with streamline query and clustering. Streamline queries allow us to rapidly identify streamlines that share similar geometric features to the target streamline. Streamline clustering allows us to group together streamlines of similar shapes. Based on users selection, different clusters with different features at different levels of detail can be visualized to highlight features in 3D flow fields. We demonstrate the utility of our framework with simulation data sets of varying nature and size.
Apparatus and method for interaction phenomena with world modules in data-flow-based simulation
Xavier, Patrick G. (Albuquerque, NM); Gottlieb, Eric J. (Corrales, NM); McDonald, Michael J. (Albuquerque, NM); Oppel, III, Fred J. (Albuquerque, NM)
A method and apparatus accommodate interaction phenomenon in a data-flow-based simulation of a system of elements, by establishing meta-modules to simulate system elements and by establishing world modules associated with interaction phenomena. World modules are associated with proxy modules from a group of meta-modules associated with one of the interaction phenomenon. The world modules include a communication world, a sensor world, a mobility world, and a contact world. World modules can be further associated with other world modules if necessary. Interaction phenomenon are simulated in corresponding world modules by accessing member functions in the associated group of proxy modules. Proxy modules can be dynamically allocated at a desired point in the simulation to accommodate the addition of elements in the system of elements such as a system of robots, a system of communication terminals, or a system of vehicles, being simulated.
Viscous potential flow analysis of electrified miscible finitely conducting fluid through porous media
Obied Allah, M. H. [Department of Mathematics, Faculty of Science, Assiut University, Assiut (Egypt)
In this work, a viscous potential flow analysis is used to investigate capillary surface waves between two horizontal finite fluid layers. The two layers have finite conductivities and admit mass and heat transfer. A general dispersion relation is derived. The presence of finite conductivities together with the dielectric permeabilities makes the horizontal electric field play a dual role in the stability criterion. The phenomenon of negative viscosity is observed. A new growth rate parameter, depending on the kinematical viscosity of the lower fluid layer, is found and has a stabilizing effect on the unstable modes. The growth rates and neutral stability curve are given and applied to air-water interface. The effects of various parameters are discussed for the Kelvin-Helmholtz and the Rayleigh-Taylor instabilities.
Preliminary Analysis of Grande Ronde Basalt Formation Flow Top Transmissivity as it Relates to Assessment and Site Selection Applications for Fluid/Energy Storage and Sequestration Projects
Spane, Frank A.
Preliminary Analysis of Grande Ronde Basalt Formation Flow Top Transmissivity as it Relates to Assessment and Site Selection Applications for Fluid/Energy Storage and Sequestration Projects
Zero-Preserving Iso-spectral Flows Based on Parallel Sums
Kenneth R. Driessel; Alf Gerisch
Driessel ["Computing canonical forms using flows", Linear Algebra and Its Applications 2004] introduced the notion of quasi-projection onto the range of a linear transformation from one inner product space into another inner product space. Here we introduce the notion of quasi-projection onto the intersection of the ranges of two linear transformations from two inner product spaces into a third inner product space. As an application, we design a new family of iso-spectral flows on the space of symmetric matrices that preserves zero patterns. We discuss the equilibrium points of these flows. We conjecture that these flows generically converge to diagonal matrices. We perform some numerical experiments with these flows which support this conjecture. We also compare our zero preserving flows with the Toda flow.
Improving parameter estimation and water table depth simulation in a land surface model using GRACE water storage and estimated base flow data
Lo, Min-Hui; Famiglietti, James S; Yeh, P. J.-F.; Syed, T. H
40, doi:10.1175/2008JHM993.1. Szilagyi, J. (2004), Heuristicsimulations of base flow [Szilagyi, 2004]. Although the
CFD Analysis of Core Bypass Flow and Crossflow in the Prismatic Very High Temperature Gas-cooled Nuclear Reactor
Wang, Huhu 1985-
if the large portion of the coolant flows into bypass gaps instead of coolant channels in which the cooling efficiency is much higher. A preliminary three dimensional steady-state CFD analysis was performed with commercial code STARCCM+ 6.04 to investigate...
Flow Injection Analysis in a Microfluidic Format Andrew M. Leach, Aaron R. Wheeler, and Richard N. Zare*
Zare, Richard N.
fabrication techniques and the use of news materials has helped the field move toward its ultimate goal of producing low-cost, disposable instrumentation. Flow injection analysis (FIA) is a widely used sampling, Polydimethylsiloxane, Microvalves #12;3 The recent trend toward miniaturized chemical assays has led to the development
Scheduling Design and Analysis for End-to-End Heterogeneous Flows in an Avionics Network
Liu, Xue
University of Science and Technology, Wuhan, China firstname.lastname@example.com Abstract--Avionics Full DupleX (AFDX heterogeneous flows, including avionics, multimedia (video & audio) and best-effort data flows, in an AFDX and sporadic flows in an AFDX prototype show the efficacy and efficiency of our proposed schemes. To the best
VFLOW2D - A Vorte-Based Code for Computing Flow Over Elastically Supported Tubes and Tube Arrays
A numerical flow model is developed to simulate two-dimensional fluid flow past immersed, elastically supported tube arrays. This work is motivated by the objective of predicting forces and motion associated with both deep-water drilling and production risers in the oil industry. This work has other engineering applications including simulation of flow past tubular heat exchangers or submarine-towed sensor arrays and the flow about parachute ribbons. In the present work, a vortex method is used for solving the unsteady flow field. This method demonstrates inherent advantages over more conventional grid-based computational fluid dynamics. The vortex method is non-iterative, does not require artificial viscosity for stability, displays minimal numerical diffusion, can easily treat moving boundaries, and allows a greatly reduced computational domain since vorticity occupies only a small fraction of the fluid volume. A gridless approach is used in the flow sufficiently distant from surfaces. A Lagrangian remap scheme is used near surfaces to calculate diffusion and convection of vorticity. A fast multipole technique is utilized for efficient calculation of velocity from the vorticity field. The ability of the method to correctly predict lift and drag forces on simple stationary geometries over a broad range of Reynolds numbers is presented.
analysis based lng: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
analysis based lng First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Floating LNG terminal and LNG...
Model-Based Dependability Analysis of Programmable Drug Infusion Pumps
Sankaranarayanan, Sriram
Model-Based Dependability Analysis of Programmable Drug Infusion Pumps Sriram email@example.com Abstract. Infusion pumps are commonly used in home/hospital care to inject drugs into a patient a case-study involving an infusion pump used to manage pain through the infusion of analgesic drugs
Model-based experimental analysis for inter-polymer process
Grossmann, Ignacio E.
) + Polyethylene (PE) ARCEL TOUGH FLEXIBLE Advanced packaging material Interpenetrating polymer network productModel-based experimental analysis for inter-polymer process CMU: Weijie Lin, Lorenz T. Biegler processed in a sequential way Polymer A Polymer B Project overview Inter-polymer process #12;Project
Analysis of Semantic Building Blocks via Grobner Bases
Fernandez, Thomas
for the space of multivariate polynomials in n variables, capable of expressing arbitrary sums and productsAnalysis of Semantic Building Blocks via Gr┬©obner Bases Jerry Swan1 , Geoffrey K. Neumann1 for greatest common divisor from univariate to multivariate polyno- mials. Since its invention in 1965, it has
GENERAL RESEARCH Real Options Based Analysis of Optimal Pharmaceutical Research
Maranas, Costas
GENERAL RESEARCH Real Options Based Analysis of Optimal Pharmaceutical Research and Development optimization model (OptFolio) of pharmaceutical research and development (R&D) portfolio management using preclinical development through FDA filing and product launch.1 A drug may spend 6-10 years
Analysis of An Adaptive Sampler Based on Weber's Law
Dabeer, Onkar
1 Analysis of An Adaptive Sampler Based on Weber's Law Onkar Dabeer Subhasis Chaudhuri Onkar Dabeer;2 Abstract Weber's law suggests a logarithmic relationship between perceptual stimuli and human perception. The Weber sampler is an adaptive, non-uniform sampling mechanism that exploits Weber's law to sample
Assessment and Event Based Analysis of Dynamic Wireless Networks
Paris-Sud XI, Universitķ de
Assessment and Event Based Analysis of Dynamic Wireless Networks Denis Carvin1,2, Guillaume Kremer1 of mobile nodes in networks is significantly changing the way they are managed. Indeed, these wireless-estimation algorithm for wireless mobile networks. We then provide events' collection and distributed mining methods
Analysis of Time Series Using Compact Model-Based Descriptions
Kriegel, Hans-Peter
Analysis of Time Series Using Compact Model-Based Descriptions Hans-Peter Kriegel, Peer Kr this is a combination of the coefficients 1, . . . , 3 representing the three input time series using a function f-of-the-art compression methods. The results are visually presented in a very concise way so that the user can easily
Analysis of Preventive Maintenance in Transactions Based Software Systems
Telek, Mikl├│s
Analysis of Preventive Maintenance in Transactions Based Software Systems Sachin Garg 1 , Antonio''. However, it incurs some overhead. The necessity to do preventive maintenance not only in general purpose to illustrate the usefulness and applicability of the models. Keywords: Preventive Maintenance, Transactions
The Comprehensive Imaging-Based Analysis of the Lung
Virginia Tech
The Comprehensive Imaging-Based Analysis of the Lung: A Forum for Team Science1 Eric A. Hoffman, Ph description and understanding of the human lung and its response to disease, injury, and treatment, which for the need to volumetrically im- age the lung and to provide objective, quantitative measures characterizing
Higher-order compositional modeling of three-phase flow in 3D fractured porous media based on cross-flow equilibrium
Moortgat, Joachim, E-mail: email@example.com; Firoozabadi, Abbas, E-mail: firstname.lastname@example.com
Numerical simulation of multiphase compositional flow in fractured porous media, when all the species can transfer between the phases, is a real challenge. Despite the broad applications in hydrocarbon reservoir engineering and hydrology, a compositional numerical simulator for three-phase flow in fractured media has not appeared in the literature, to the best of our knowledge. In this work, we present a three-phase fully compositional simulator for fractured media, based on higher-order finite element methods. To achieve computational efficiency, we invoke the cross-flow equilibrium (CFE) concept between discrete fractures and a small neighborhood in the matrix blocks. We adopt the mixed hybrid finite element (MHFE) method to approximate convective Darcy fluxes and the pressure equation. This approach is the most natural choice for flow in fractured media. The mass balance equations are discretized by the discontinuous Galerkin (DG) method, which is perhaps the most efficient approach to capture physical discontinuities in phase properties at the matrix-fracture interfaces and at phase boundaries. In this work, we account for gravity and Fickian diffusion. The modeling of capillary effects is discussed in a separate paper. We present the mathematical framework, using the implicit-pressure-explicit-composition (IMPEC) scheme, which facilitates rigorous thermodynamic stability analyses and the computation of phase behavior effects to account for transfer of species between the phases. A deceptively simple CFL condition is implemented to improve numerical stability and accuracy. We provide six numerical examples at both small and larger scales and in two and three dimensions, to demonstrate powerful features of the formulation.
October 2000 2000, Elsevier Science Inc., 1040-6190/00/$see front matter PII S1040-6190(00)00146-9 38 Flow-Based Transmission
Oren, Shmuel S.
-6190(00)00146-9 38 Flow-Based Transmission Rights and Congestion Management Combining the advantages of financial and physical rights, a flow-based transmission reservation approach facilitates liquidity and efficient risk decade, important issues remain unsettled concerning the best way to organize transmission to support
Flow Characteristics Analysis of Widows' Creek Type Control Valve for Steam Turbine Control
Yoo, Yong H.; Sohn, Myoung S.; Suh, Kune Y. [PHILOSOPHIA, Inc., Seoul National University, San 56-1 Sillim-dong, Gwanak-gu, Seoul, 151-742 (Korea, Republic of)
The steam turbine converts the kinetic energy of steam to mechanical energy of rotor blades in the power conversion system of fossil and nuclear power plants. The electric output from the generator of which the rotor is coupled with that of the steam turbine depends on the rotation velocity of the steam turbine bucket. The rotation velocity is proportional to the mass flow rate of steam entering the steam turbine through valves and nozzles. Thus, it is very important to control the steam mass flow rate for the load following operation of power plants. Among various valves that control the steam turbine, the control valve is most significant. The steam flow rate is determined by the area formed by the stem disk and the seat of the control valve. While the ideal control valve linearly controls the steam mass flow rate with its stem lift, the real control valve has various flow characteristic curves pursuant to the stem lift type. Thus, flow characteristic curves are needed to precisely design the control valves manufactured for the operating conditions of nuclear power plants. OMEGA (Optimized Multidimensional Experiment Geometric Apparatus) was built to experimentally study the flow characteristics of steam flowing inside the control valve. The Widows' Creek type control valve was selected for reference. Air was selected as the working fluid in the OMEGA loop to exclude the condensation effect in this simplified approach. Flow characteristic curves were plotted by calculating the ratio of the measured mass flow rate versus the theoretical mass flow rate of the air. The flow characteristic curves are expected to be utilized to accurately design and operate the control valve for fossil as well as nuclear plants. (authors)
An analysis of an application of radioactive ionization for gas flow metering
Lam, Carroll Frank
OF FIGURES CHAP TER I. INTRODUCTION II. EXPERIMENTAL PROCEDURE III. MEASUREMENT OF MARK I CHARACTERISTICS IV. MEASUREMENT OF MARK II CHARACTERISTICS -3 V. CONCLUSIONS . 17 35 BIBLIOGRAPHY . 37 LIST OF FIGURES FIGURE PAGE 1. A Diagram of Rutherford...'s Apparatus Z. An Ezperimental Flow Meter . 3. Mark I Meter and Test Equipment 4. Electrical Circuit 5. Current vs. Flow Rate Curve for Mark I Meter. . . . . . . . . . . . . 6. Current vs. Flow Rate for DifferentSource Spacings. . . . . . . . . . 7...
Mechanical analysis of a cross flow filter. Final report, January 31, 1995
A cross flow filter for particulate control is described. Objectives were to improve the reliability and mechanical integrity of the filter.
Purged window apparatus. [On-line spectroscopic analysis of gas flow systems
Ballard, E.O.
A purged window apparatus is described which utilizes tangentially injected heated purge gases in the vicinity of electromagnetic radiation transmitting windows and a tapered external mounting tube to accelerate these gases to provide a vortex flow on the window surface and a turbulent flow throughout the mounting tube thereby preventing backstreaming of flowing gases under investigation in a chamber to which a plurality of similar purged apparatus is attached with the consequent result that spectroscopic analyses can be undertaken for lengthy periods without the necessity of interrupting the flow for cleaning or replacing the windows due to contamination.
Fourier-Based Spectral Analysis with Adaptive Resolution
Andrey Khilko
Despite being the most popular methods of data analysis, Fourier-based techniques suffer from the problem of static resolution that is currently believed to be a fundamental limitation of the Fourier Transform. Although alternative solutions overcome this limitation, none provide the simplicity, versatility, and convenience of the Fourier analysis. The lack of convenience often prevents these alternatives from replacing classical spectral methods - even in applications that suffer from the limitation of static resolution. This work demonstrates that, contrary to the generally accepted belief, the Fourier Transform can be generalized to the case of adaptive resolution. The generalized transform provides backward compatibility with classical spectral techniques and introduces minimal computational overhead.
Automatic generation of skeletal mechanisms for ignition combustion based on level of importance analysis
Loevaas, Terese [School of Engineering and Materials Sciences, Queen Mary University of London, London E1 4NS (United Kingdom); Department of Engineering and Economy, University of Tromsoe, 9012 Tromsoe (Norway)
A level of importance (LOI) selection parameter is employed in order to identify species with general low importance to the overall accuracy of a chemical model. This enables elimination of the minor reaction paths in which these species are involved. The generation of such skeletal mechanisms is performed automatically in a pre-processing step ranking species according to their level of importance. This selection criterion is a combined parameter based on a time scale and sensitivity analysis, identifying both short lived species and species with respect to which the observable of interest has low sensitivity. In this work a careful element flux analysis demonstrates that such species do not interact in major reaction paths. Employing the LOI procedure replaces the previous method of identifying redundant species through a two step procedure involving a reaction flow analysis followed by a sensitivity analysis. The flux analysis is performed using DARS {sup copyright}, a digital analysis tool modelling reactive systems. Simplified chemical models are generated based on a detailed ethylene mechanism involving 111 species and 784 reactions (1566 forward and backward reactions) proposed by Wang et al. Eliminating species from detailed mechanisms introduces errors in the predicted combustion parameters. In the present work these errors are systematically studied for a wide range of conditions, including temperature, pressure and mixtures. Results show that the accuracy of simplified models is particularly lowered when the initial temperatures are close to the transition between low- and high-temperature chemistry. A speed-up factor of 5 is observed when using a simplified model containing only 27% of the original species and 19% of the original reactions. (author)
Analysis of wind turbine vibrations based on SCADA data
Andrew Kusiak; Zijun Zhang
Vibrations of a wind turbine have a negative impact on its performance. Mitigating this undesirable impact requires knowledge of the relationship between the vibrations and other wind turbine parameters that could be potentially modified. Three approaches for ranking the impact importance of measurable turbine parameters on the vibrations of the drive train and the tower are discussed. They include the predictor importance analysis, the global sensitivity analysis, and the correlation coefficient analysis versed in data mining and statistics. To decouple the impact of wind speed on the vibrations of the drive train and the tower, the analysis is performed on data sets with narrow speed ranges. Wavelet analysis is applied to filter noisy accelerometer data. To exclude the impact malfunctions on the vibration analysis, the data are analyzed in a frequency domain. Data-mining algorithms are used to build models with turbine parameters of interest as inputs, and the vibrations of drive train and tower as outputs. The performance of each model is thoroughly evaluated based on metrics widely used in the wind industry. The neural network algorithm outperforms other classifiers and is considered to be the most promising approach to study wind turbine vibrations. ?DOI: 10.1115/1.4001461?
Anisotropy and mantle flow in the Chile-Argentina subduction zone from shear wave splitting analysis
Fouch, Matthew J.
Anisotropy and mantle flow in the Chile-Argentina subduction zone from shear wave splitting subduction zone. Data is from the CHARGE network, which traversed Chile and western Argentina across two, M. L., G. Zandt, E. Triep, M. Fouch, and S. Beck (2004), Anisotropy and mantle flow in the Chile-Argentina
Analysis of No-Flow Boundaries in Mixed Unconfined-Confined Aquifer Systems
Langerlan, Kent A.
investigated before and is the focus of this thesis. The objective of this thesis is to use both analytical and numerical modeling to investigate groundwater flow in an unconfined-confined aquifer including the no-flow lateral boundary effect and the regional...
Anisotropic output-based adaptation with tetrahedral cut cells for compressible flows
Park, Michael Andrew
Anisotropic, adaptive meshing for flows around complex, three-dimensional bodies remains a barrier to increased automation in computational fluid dynamics. Two specific advances are introduced in this thesis. First, a ...
Tariff-based analysis of commercial building electricityprices
Coughlin, Katie M.; Bolduc, Chris A.; Rosenquist, Greg J.; VanBuskirk, Robert D.; McMahon, James E.
This paper presents the results of a survey and analysis ofelectricity tariffs and marginal electricity prices for commercialbuildings. The tariff data come from a survey of 90 utilities and 250tariffs for non-residential customers collected in 2004 as part of theTariff Analysis Project at LBNL. The goals of this analysis are toprovide useful summary data on the marginal electricity prices commercialcustomers actually see, and insight into the factors that are mostimportant in determining prices under different circumstances. We providea new, empirically-based definition of several marginal prices: theeffective marginal price and energy-only anddemand-only prices, andderive a simple formula that expresses the dependence of the effectivemarginal price on the marginal load factor. The latter is a variable thatcan be used to characterize the load impacts of a particular end-use orefficiency measure. We calculate all these prices for eleven regionswithin the continental U.S.
Development of one-dimensional computational fluid dynamics code 'GFLOW' for groundwater flow and contaminant transport analysis
Rahatgaonkar, P. S.; Datta, D.; Malhotra, P. K.; Ghadge, S. G. [Nuclear Power Corporation of India Ltd., R-2, Ent. Block, Nabhikiya Urja Bhavan, Anushakti Nagar, Mumbai - 400 094 (India)
Prediction of groundwater movement and contaminant transport in soil is an important problem in many branches of science and engineering. This includes groundwater hydrology, environmental engineering, soil science, agricultural engineering and also nuclear engineering. Specifically, in nuclear engineering it is applicable in the design of spent fuel storage pools and waste management sites in the nuclear power plants. Ground water modeling involves the simulation of flow and contaminant transport by groundwater flow. In the context of contaminated soil and groundwater system, numerical simulations are typically used to demonstrate compliance with regulatory standard. A one-dimensional Computational Fluid Dynamics code GFLOW had been developed based on the Finite Difference Method for simulating groundwater flow and contaminant transport through saturated and unsaturated soil. The code is validated with the analytical model and the benchmarking cases available in the literature. (authors)
Weather data analysis based on typical weather sequence analysis. Application: energy building simulation
David, Mathieu; Garde, Francois; Boyer, Harry
In building studies dealing about energy efficiency and comfort, simulation software need relevant weather files with optimal time steps. Few tools generate extreme and mean values of simultaneous hourly data including correlation between the climatic parameters. This paper presents the C++ Runeole software based on typical weather sequences analysis. It runs an analysis process of a stochastic continuous multivariable phenomenon with frequencies properties applied to a climatic database. The database analysis associates basic statistics, PCA (Principal Component Analysis) and automatic classifications. Different ways of applying these methods will be presented. All the results are stored in the Runeole internal database that allows an easy selection of weather sequences. The extreme sequences are used for system and building sizing and the mean sequences are used for the determination of the annual cooling loads as proposed by Audrier-Cros (Audrier-Cros, 1984). This weather analysis was tested with the datab...
Kelvin-Helmholtz instability for flow in porous media under the influence of oblique magnetic fields: A viscous potential flow analysis
Moatimid, Galal M. [Department of Mathematics, Faculty of Science, University of Tabuk, Tabuk, P.O. Box 741 (Saudi Arabia)] [Department of Mathematics, Faculty of Science, University of Tabuk, Tabuk, P.O. Box 741 (Saudi Arabia); Obied Allah, M. H. [Department of Mathematics, Faculty of Science, Assiut University, Assiut (Egypt)] [Department of Mathematics, Faculty of Science, Assiut University, Assiut (Egypt); Hassan, Mohamed A. [Department of Mathematics, Faculty of Education, Ain Shams University, Roxy, Cairo (Egypt)] [Department of Mathematics, Faculty of Education, Ain Shams University, Roxy, Cairo (Egypt)
In this paper, the Kelvin-Helmholtz instability of viscous incompressible magnetic fluid fully saturated porous media is achieved through the viscous potential theory. The flow is considered to be through semi-permeable boundaries above and below the fluids through which the fluid may either be blown in or sucked out, in a direction normal to the main streaming direction of the fluid flow. An oblique magnetic field, mass, heat transfer, and surface tension are present across the interface. Through the linear stability analysis, a general dispersion relation is derived and the natural curves are plotted. Therefore, the linear stability condition is discussed in some depth. In view of the multiple time scale technique, the Ginzburg¢Landau equation, which describes the behavior of the system in the nonlinear approach, is obtained. The effects of the orientation of the magnetic fields on the stability configuration in linear, as well as nonlinear approaches, are discussed. It is found that the Darcy's coefficient for the porous layers plays a stabilizing role. The injection of the fluids at both boundaries has a stabilizing effect, in contrast with the suction at both boundaries.
Nonrigid Motion Analysis Based on Dynamic Refinement of Finite Element Models
Sarkar, Sudeep
Nonrigid Motion Analysis Based on Dynamic Refinement of Finite Element Models Leonid V. Tsap finite element models. The method is based on the iterative analysis of the differences between├ÉPhysically-based vision, deformable models, nonrigid motion analysis, biomedical applications, finite element analysis. ├"
An improved multiscale model for dilute turbulent gas particle flows based on the equilibration of energy concept
Xu, Ying
Many particle-laden flows in engineering applications involve turbulent gas flows. Modeling multiphase turbulent flows is an important research topic with applications in fluidized beds and particle conveying. A predictive multiphase turbulence model can help CFD codes to be more useful for engineering applications, such as the scale-up in the design of circulating fluidized combustor and coal gasifications. In engineering applications, the particle volume fraction can vary from dilute (<10{sup -4}) to dense ({approx} 50%). It is reasonable to expect that multiphase turbulence models should at least satisfy some basic modeling and performance criteria and give reasonable predictions for the canonical problems in dilute particle-laden turbulent flows. In this research, a comparative assessment of predictions from Simonin and Ahmadi's turbulence models is performed with direct numerical simulation (DNS) for two canonical problems in particle-laden turbulent flows. Based on the comparative assessment, some criteria and the areas for model improvement are identified: (1) model for interphase TKE transfer, especially the time scale of interphase TKE transfer, and (2) correct prediction of TKE evolution with variation of particle Stokes number. Some deficiencies that are identified in the Simonin and Ahmadi models, limit the applicability. A new multiphase turbulence model, the Equilibration of Energy Model (EEM), is proposed in this work. In EEM, a multiscale interaction time scale is proposed to account for the interaction of a particle with a range of eddy sizes. EEM shows good agreement with the DNS results for particle-laden isotropic turbulence. For particle-laden homogeneous shear flows, model predictions from EEM can be further improved if the dissipation rate in fluid phase is modeled with more accuracy.
Sensitivity analysis of aquifer parameter estimations based on the Laplace equation with linearized boundary conditions
Szilagyi, Jozsef
boundary conditions Jozsef Szilagyi Conservation and Survey Division, University of Nebraska analysis Citation: Szilagyi, J., Sensitivity analysis of aquifer parameter estimations based on the Laplace
SNP-based pathway enrichment analysis for genome-wide association studies
SNP: applying gene set enrichment analysis to SNP data fromdetection of pathway enrichment in genome-wide associational. : SNP-based pathway enrichment analysis for genome-wide
Analysis of multiphase fluid flows via high speed and synthetic aperture three dimensional imaging
Scharfman, Barry Ethan
Spray flows are a difficult problem within the realm of fluid mechanics because of the complicated interfacial physics involved. Complete models of sprays having even the simplest geometries continue to elude researchers ...
A Novel Power Flow Method for Long Term Frequency Stability AnalysisĀ
Yan, Wenjin
This thesis presents a novel approach for a power system to find a practical power flow solution when all the generators in the system have hit their real power output limits, such as some generator units shutting down or ...
Fusion Engineering and Design 82 (2007) 22172225 Integrated thermo-fluid analysis towards helium flow
Abdou, Mohamed
flow path design for an ITER solid breeder blanket module A. Yinga,, M. Narulaa, R. Hunta, M. Abdoua, Y breeder blanket design. Supplying all s the ITER test blanket module (TBM) warrants the need of extensive computer aided engineering (CAE
Rheo-PIV Analysis of the Yielding and Flow of Model Waxy Crude Oils
Dimitriou, Christopher J.
Waxes are a commonly encountered precipitate that can result in the gelation of crude oils and cessation of flow in pipelines. In this work, we develop a model wax¢oil system that exhibits rheological behavior similar to ...
Wavelet analysis study of microbubble drag reduction in a boundary channel flowĀ
Zhen, Ling
Particle Image Velocimetry (PIV) and pressure measurement techniques were performed to investigate the drag reduction due to microbubble injection in the boundary layer of a fully developed turbulent channel flow. ...
A graph-based system for network-vulnerability analysis
Swiler, L.P.; Phillips, C.
This paper presents a graph-based approach to network vulnerability analysis. The method is flexible, allowing analysis of attacks from both outside and inside the network. It can analyze risks to a specific network asset, or examine the universe of possible consequences following a successful attack. The graph-based tool can identify the set of attack paths that have a high probability of success (or a low effort cost) for the attacker. The system could be used to test the effectiveness of making configuration changes, implementing an intrusion detection system, etc. The analysis system requires as input a database of common attacks, broken into atomic steps, specific network configuration and topology information, and an attacker profile. The attack information is matched with the network configuration information and an attacker profile to create a superset attack graph. Nodes identify a stage of attack, for example the class of machines the attacker has accessed and the user privilege level he or she has compromised. The arcs in the attack graph represent attacks or stages of attacks. By assigning probabilities of success on the arcs or costs representing level-of-effort for the attacker, various graph algorithms such as shortest-path algorithms can identify the attack paths with the highest probability of success.
A general nonlinear least squares data reconciliation and estimation method for material flow analysis
Kopec, Grant M.; Allwood, Julian M.; Cullen, Jonathan M.; Ralph, Daniel
reconciliation in problems with nonlinear constraints. This formulation relates measurements of flow rate, temperature, and pressure, so the specific equations may be less appropriate for MFA data reconciliation, though the basic methodology is applicable... to satisfy the structural constraints of mass flow and conservation of mass. For example, data from the World Steel Association (2010) indicates that 44.5 Mt of steel were used for welded tube in 2009, but the value that Cullen et al. (2012a) assign is 62...
Modeling, Analysis and Simulation of Multiscale Preferential Flow - 8/05-8/10 - Final Report
Ralph Showalter; Malgorzata Peszynska
The research agenda of this project are: (1) Modeling of preferential transport from mesoscale to macroscale; (2) Modeling of fast flow in narrow fractures in porous media; (3) Pseudo-parabolic Models of Dynamic Capillary Pressure; (4) Adaptive computational upscaling of flow with inertia from porescale to mesoscale; (5) Adaptive modeling of nonlinear coupled systems; and (6) Adaptive modeling and a-posteriori estimators for coupled systems with heterogeneous data.
Loading and Regeneration Analysis of a Diesel Particulate Filter with a Radio Frequency-Based Sensor
Sappok, Alex [Filter Sensing Technologies] [Filter Sensing Technologies; Prikhodko, Vitaly Y [ORNL] [ORNL; Parks, II, James E [ORNL
Accurate knowledge of diesel particulate filter (DPF) loading is critical for robust and efficient operation of the combined engine-exhaust aftertreatment system. Furthermore, upcoming on-board diagnostics regulations require on-board technologies to evaluate the status of the DPF. This work describes the application of radio frequency (RF) based sensing techniques to accurately measure DPF soot levels and the spatial distribution of the accumulated material. A 1.9L GM turbo diesel engine and a DPF with an RF-sensor were studied. Direct comparisons between the RF measurement and conventional pressure-based methods were made. Further analysis of the particulate matter loading rates was obtained with a mass-based soot emission measurement instrument (TEOM). Comparison with pressure drop measurements show the RF technique is unaffected by exhaust flow variations and exhibits a high degree of sensitivity to DPF soot loading and good dynamic response. Additional computational and experimental work further illustrates the spatial resolution of the RF measurements. Based on the experimental results, the RF technique shows significant promise for improving DPF control enabling optimization of the combined engine-aftertreatment system for improved fuel economy and extended DPF service life.
Normalization and Statistical Analysis of Multiplexed Bead-Based Immunoassay Data Using Mixed-Effects Modeling
Clarke, David C.
Multiplexed bead-based flow cytometric immunoassays are a powerful experimental tool for investigating cellular communication networks, yet their widespread adoption is limited in part by challenges in robust quantitative ...
A Zonotope-Based Method for Capturing the Effect of Variable Generation on the Power Flow
Liberzon, Daniel
of a power system; this uncertainty arises from the increasing penetration of renewable resources that the uncertain generation can take by a zonotope and propagate it through a linearized power flow model take values within a symmetric polytope. This uncertainty is propagated through the power system model
Nonlinear model-based control of two-phase flow in risers by feedback linearization
Skogestad, Sigurd
systems, stabilizing control. 1. INTRODUCTION When a new small oil reservoir is discovered, long subsea transport technology and flow assurance become more important. Especially depleted reservoirs have low as well as by experiments on a test rig. Keywords: Oil production, anti-slug control, nonlinear cascade
A Continuity Equation Based Optical Flow Method for Cardiac Motion Correction in 3D
Burger, Martin
: Motion correction, Optical Flow, PET, CT, Mass Conser- vation 1 Introduction PET (Positron Emission correction, as in the case of modern PET/CT scanners. The CT data represents a snapshot in comparison to the PET images and therefore, the PET data is not always in spatial correspondence with the CT data. One
Experiences and Challenges Scaling PFLOTRAN, a PETSc-based Code for Subsurface Reactive Flow Simulations,
Mills, Richard
and dis- cretization PFLOTRAN solves a coupled system of continuum scale mass and energy conservation in the flow module of PFLOTRAN for mass and energy conservation can be summarized as [1]: t sX i + Ę qX i the mole fraction of species i; , H, U refer to the molar density, enthalpy, and internal energy of each
Lossless droplet transfer of droplet-based microfluidic analysis
Kelly, Ryan T (West Richland, WA); Tang, Keqi (Richland, WA); Page, Jason S (Kennewick, WA); Smith, Richard D (Richland, WA)
A transfer structure for droplet-based microfluidic analysis is characterized by a first conduit containing a first stream having at least one immiscible droplet of aqueous material and a second conduit containing a second stream comprising an aqueous fluid. The interface between the first conduit and the second conduit can define a plurality of apertures, wherein the apertures are sized to prevent exchange of the first and second streams between conduits while allowing lossless transfer of droplets from the first conduit to the second conduit through contact between the first and second streams.
MEMBRANELESS FUEL CELL BASED ON LAMINAR FLOW Eric R. Choban, Piotr Waszczuk, Larry J. Markoski, Andrzej Wieckowski, and Paul J.A. Kenis*
Kenis, Paul J. A.
MEMBRANELESS FUEL CELL BASED ON LAMINAR FLOW Eric R. Choban, Piotr Waszczuk, Larry J. Markoski in this area focus on downscaling of existing fuel cell technology such as the well-known proton exchange membrane (PEM) fuel cells. Here we study a novel concept for fuel cells: the use of laminar flow instead
Quantifying Distributed System Stability through Simulation: A Case Study of an Agent-Based System for Flow Reconstruction of DDoS Attacks
Khan, Bilal
Quantifying Distributed System Stability through Simulation: A Case Study of an Agent-Based System for Flow Reconstruction of DDoS Attacks Omer Demir Department of Computer Science City University of New denial of service (DDoS) attacks. The pro- posed system provides a description of the structure of flows
Sensitivity analysis of GSI based mechanical characterization of rock mass
Vßn, P
Recently, the rock mechanical and rock engineering designs and calculations are frequently based on Geological Strength Index (GSI) method, because it is the only system that provides a complete set of mechanical properties for design purpose. Both the failure criteria and the deformation moduli of the rock mass can be calculated with GSI based equations, which consists of the disturbance factor, as well. The aim of this paper is the sensitivity analysis of GSI and disturbance factor dependent equations that characterize the mechanical properties of rock masses. The survey of the GSI system is not our purpose. The results show that the rock mass strength calculated by the Hoek-Brown failure criteria and both the Hoek-Diederichs and modified Hoek-Diederichs deformation moduli are highly sensitive to changes of both the GSI and the D factor, hence their exact determination is important for the rock engineering design.
Analysis Of Residence Time Distribution Of Fluid Flow By Axial Dispersion Model
Sugiharto [Department of Physics, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Jl. Ganesha 10, Bandung 40132 (Indonesia); Centre for Applications of Isotopes and Radiation Technology-National Nuclear Energy Agency, Jl. Lebak Bulus Raya No. 49, Jakarta 12440 (Indonesia); Su'ud, Zaki; Kurniadi, Rizal; Waris, Abdul [Centre for Applications of Isotopes and Radiation Technology-National Nuclear Energy Agency, Jl. Lebak Bulus Raya No. 49, Jakarta 12440 (Indonesia); Abidin, Zainal [Department of Physics, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Jl. Ganesha 10, Bandung 40132 (Indonesia)
Radioactive tracer {sup 82}Br in the form of KBr-82 with activity {+-} 1 mCi has been injected into steel pipeline to qualify the extent dispersion of water flowing inside it. Internal diameter of the pipe is 3 in. The water source was originated from water tank through which the water flow gravitically into the pipeline. Two collimated sodium iodide detectors were used in this experiment each of which was placed on the top of the pipeline at the distance of 8 and 11 m from injection point respectively. Residence time distribution (RTD) curves obtained from injection of tracer are elaborated numerically to find information of the fluid flow properties. The transit time of tracer calculated from the mean residence time (MRT) of each RTD curves is 14.9 s, therefore the flow velocity of the water is 0.2 m/s. The dispersion number, D/uL, for each RTD curve estimated by using axial dispersion model are 0.055 and 0.06 respectively. These calculations are performed after fitting the simulated axial dispersion model on the experiment curves. These results indicated that the extent of dispersion of water flowing in the pipeline is in the category of intermediate.
A Lagrangian analysis of advection-diffusion equation for a three dimensional chaotic flow
Tang, X.Z. [Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States)] [Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States); Boozer, A.H. [Department of Applied Physics, Columbia University, New York, New York 10027 (United States)] [Department of Applied Physics, Columbia University, New York, New York 10027 (United States); [Max-Planck Institut fuer Plasmaphysik, Garching (Germany)
The advection-diffusion equation is studied via a global Lagrangian coordinate transformation. The metric tensor of the Lagrangian coordinates couples the dynamical system theory rigorously into the solution of this class of partial differential equations. If the flow has chaotic streamlines, the diffusion will dominate the solution at a critical time, which scales logarithmically with the diffusivity. The subsequent rapid diffusive relaxation is completed on the order of a few Lyapunov times, and it becomes more anisotropic the smaller the diffusivity. The local Lyapunov time of the flow is the inverse of the finite time Lyapunov exponent. A finite time Lyapunov exponent can be expressed in terms of two convergence functions which are responsible for the spatio-temporal complexity of both the advective and diffusive transports. This complexity gives a new class of diffusion barrier in the chaotic region and a fractal-like behavior in both space and time. In an integrable flow with shear, there also exist fast and slow diffusion. But unlike that in a chaotic flow, a large gradient of the scalar field across the KAM surfaces can be maintained since the fast diffusion in an integrable flow is strictly confined within the KAM surfaces. {copyright} {ital 1999 American Institute of Physics.}
Columbia University flow instability experimental program: Volume 2. Single tube uniformly heated tests -- Part 2: Uncertainty analysis and data
Dougherty, T.; Maciuca, C.; McAssey, E.V. Jr.; Reddy, D.G.; Yang, B.W.
In June 1988, Savannah River Laboratory requested that the Heat Transfer Research Facility modify the flow excursion program, which had been in progress since November 1987, to include testing of single tubes in vertical down-flow over a range of length to diameter (L/D) ratios of 100 to 500. The impetus for the request was the desire to obtain experimental data as quickly as possible for code development work. In July 1988, HTRF submitted a proposal to SRL indicating that by modifying a facility already under construction the data could be obtained within three to four months. In January 1990, HTFR issued report CU-HTRF-T4, part 1. This report contained the technical discussion of the results from the single tube uniformly heated tests. The present report is part 2 of CU-HTRF-T4 which contains further discussion of the uncertainty analysis and the complete set of data.
Draft of Preliminary Syllabus Applying Geospatial Analysis-Project Based Learning
Fabrikant, Sara Irina
Draft of Preliminary Syllabus Applying Geospatial Analysis- Project Based Learning Listed as, and analysis (2) formulate and evaluate research questions relating to geospatial approaches (3) learn geospatial techniques (4) learn data management, data conversion, and data analysis (5) apply geospatial
Poiseuille flow past a nanoscale cylinder in a slit channel: Lubrication theory versus molecular dynamics analysis
Rahmani, Amir M; Jupiterwala, Mehlam; Colosqui, Carlos E
Plane Poiseuille flow past a nanoscale cylinder that is arbitrarily confined (i.e., symmetrically or asymmetrically confined) in a slit channel is studied via hydrodynamic lubrication theory and molecular dynamics simulations, considering cases where the cylinder remains static or undergoes thermal motion. Lubrication theory predictions for the drag force and volumetric flow rate are in close agreement with molecular dynamics simulations of flows having molecularly thin lubrication gaps, despite the presence of significant structural forces induced by the crystalline structure of the modeled solid. While the maximum drag force is observed in symmetric confinement, i.e., when the cylinder is equidistant from both channel walls, the drag decays significantly as the cylinder moves away from the channel centerline and approaches a wall. Hence, significant reductions in the mean drag force on the cylinder and hydraulic resistance of the channel can be observed when thermal motion induces random off-center displace...
Linear and nonlinear stability analysis for two-dimensional ideal magnetohydrodynamics with incompressible flows
Khater, A.H.; Moawad, S.M.; Callebaut, D.K. [Department of Mathematics, Faculty of Science, Cairo University, Beni-Suef (Egypt); Departement Natuurkunde, Campus Drie Eiken, Universiteit Antwerpen - UA, B-2610 Antwerpen (Belgium)
The equilibrium and Lyapunov stability properties for two-dimensional ideal magnetohydrodynamic (MHD) plasmas with incompressible and homogeneous (i.e., constant density) flows are investigated. In the unperturbed steady state, both the velocity and magnetic field are nonzero and have three components in a Cartesian coordinate system with translational symmetry (i.e., one ignorable spatial coordinate). It is proved that (a) the solutions of the ideal MHD steady state equations with incompressible and homogeneous flows in the plane are also valid for equilibria with the axial velocity component being a free flux function and the axial magnetic field component being a constant (b) the conditions of linearized Lyapunov stability for these MHD flows in the planar case (in which the fields have only two components) are also valid for symmetric equilibria that have a nonplanar velocity field component as well as a nonplanar magnetic field component. On using the method of convexity estimates, nonlinear stability conditions are established.
Perturbative analysis of sheared flow Kelvin-Helmholtz instability in a weakly relativistic magnetized electron fluid
Sundar, Sita; Das, Amita; Kaw, Predhiman [Institute for Plasma Research, Bhat, Gandhinagar-382428 (India)
In the interaction of intense lasers with matter/plasma, energetic electrons having relativistic energies get created. These energetic electrons can often have sheared flow profiles as they propagate through the plasma medium. In an earlier study [Phys. Plasmas 17, 022101 (2010)], it was shown that a relativistic sheared electron flow modifies the growth rate and threshold condition of the conventional Kelvin-Helmholtz instability. A perturbative analytic treatment for the case of weakly relativistic regime has been provided here. It provides good agreement with the numerical results obtained earlier.
Flow induced vibration of a cantilever column jet: a spectral analysis
Shilling, Roy Bryant
, both the pump and the test di scharge pipe were mounted on a carriage whiLh oscil]ated on the track above a water sump. They were connected from the suction end by two-inch I. D. gal- vanized pipe joined in the center by a 1. 5 inch orifice plate... SPECTRUM AT 3. 5 HZ, EMPTY PIPE . FORCED VIBRATION SPECTRUM AT 3. 5 HZ, 47 fps FLOW VELOCITY- FROCED VIBRATION SPECTRUM AT 4. 58 HZ EMPTY PIPE . FORCED VIBRATION SPECTRUM AT 4. 58 HZ 10 fps FLOW VELOCITY . MIDRANGE DYNAMICS . INTENSITY RESPONSE...
The Fourier-Like and Hartley-Like Wavelet Analysis Based on Hilbert Transforms
Soares, L R; Cintra, R J
In continuous-time wavelet analysis, most wavelet present some kind of symmetry. Based on the Fourier and Hartley transform kernels, a new wavelet multiresolution analysis is proposed. This approach is based on a pair of orthogonal wavelet functions and is named as the Fourier-Like and Hartley-Like wavelet analysis. A Hilbert transform analysis on the wavelet theory is also included.
On Smoothing Surfaces in Voxel Based Finite Element Analysis of Trabecular Bone
Frey, Pascal
On Smoothing Surfaces in Voxel Based Finite Element Analysis of Trabecular Bone Peter Arbenz on complicated domains composed of often hundreds of millions of voxel elements. The finite element analysis finite element (FE) analysis. The approach based on the FE analysis leads to linear systems of equations
A graph-based network-vulnerability analysis system
Swiler, L.P.; Phillips, C.; Gaylor, T.
This paper presents a graph based approach to network vulnerability analysis. The method is flexible, allowing analysis of attacks from both outside and inside the network. It can analyze risks to a specific network asset, or examine the universe of possible consequences following a successful attack. The analysis system requires as input a database of common attacks, broken into atomic steps, specific network configuration and topology information, and an attacker profile. The attack information is matched with the network configuration information and an attacker profile to create a superset attack graph. Nodes identify a stage of attack, for example the class of machines the attacker has accessed and the user privilege level he or she has compromised. The arcs in the attack graph represent attacks or stages of attacks. By assigning probabilities of success on the arcs or costs representing level of effort for the attacker, various graph algorithms such as shortest path algorithms can identify the attack paths with the highest probability of success.
A graph-based network-vulnerability analysis system
Swiler, L.P.; Phillips, C. [Sandia National Labs., Albuquerque, NM (United States); Gaylor, T. [3M, Austin, TX (United States). Visual Systems Div.
This report presents a graph-based approach to network vulnerability analysis. The method is flexible, allowing analysis of attacks from both outside and inside the network. It can analyze risks to a specific network asset, or examine the universe of possible consequences following a successful attack. The analysis system requires as input a database of common attacks, broken into atomic steps, specific network configuration and topology information, and an attacker profile. The attack information is matched with the network configuration information and an attacker profile to create a superset attack graph. Nodes identify a stage of attack, for example the class of machines the attacker has accessed and the user privilege level he or she has compromised. The arcs in the attack graph represent attacks or stages of attacks. By assigning probabilities of success on the arcs or costs representing level-of-effort for the attacker, various graph algorithms such as shortest-path algorithms can identify the attack paths with the highest probability of success.
Turbulent Flow Analysis and Coherent Structure Identification in Experimental Models with Complex Geometries
Amini, Noushin
through the core of an annular pebble bed VHTR. The complex geometry of the core and the highly turbulent nature of the coolant flow passing through the gaps of fuel pebbles make this case quite challenging. In this experiment, a high frequency Hot Wire...
A Novel Power Flow Method for Long Term Frequency Stability Analysis
Yan, Wenjin
This thesis presents a novel approach for a power system to find a practical power flow solution when all the generators in the system have hit their real power output limits, such as some generator units shutting down or load outages. The approach...
to the additional nonlinearity in the momentum equation. For example, unlike the Darcy flows, there is no Kruzkov in porous media using generalized Forchheimer equations and the capillary pressure. Firstly, we find stability of those steady states. The linearized system is derived and reduced to a parabolic equation
Wavelet analysis study of microbubble drag reduction in a boundary channel flow
Zhen, Ling
with single phase channel flow characteristics. A drag reduction of 38.4% was achieved with void fraction of 4.9%. The measurements were analyzed by studying the turbulence characteristics utilizing wavelet techniques. The wavelet cross-correlation and auto...
Stochastic analysis of transient flow to a well in a heterogeneous aquifer
Kurien, Susan
of Arizona) Mentors: Shlomo P. Neuman (U of Arizona) Daniel Tartakovsky (LANL-T7) Introduction of potable water on Earth. The term groundwater is usually used to describe water that is beneath the water groundwater flow are generally uncertain in their exact nature, magnitude, and spatio- temporal distribution
Fluid flow near reservoir lakes inferred from the spatial and temporal analysis of the electric potential
Adolphs, Ralph
, 2002. 1. Introduction [2] Detecting subsurface groundwater circulation using geophysical methods to result from the electrokinetic coupling associated with a vertical groundwater flow connecting a constant pore pressure source to the bottom of the lakes. Numerical modeling indicates that the spatial
A stochastic analysis of transient two-phase flow in heterogeneous porous media
Lu, Zhiming
the finite element heat and mass (FEHM) transfer code, whose results are considered ``true'' solutions equation (KLME) approach is implemented to model stochastic transient water-NAPL two-phase flow model and Parker and Lenhard models are adopted. The log-transformed intrinsic permeability, soil pore
FRAC-STIM: A Physics-Based Fracture Simulation, /reservoir Flow...
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Simulator track 4: enhanced geothermal systems (EGS) | geothermal 2015 peer review Fracture Characterization in Enhanced Geothermal Systems by Wellbore and Reservoir Analysis...
Survey of sampling-based methods for uncertainty and sensitivity analysis.
Johnson, Jay Dean; Helton, Jon Craig; Sallaberry, Cedric J. PhD. (.; .); Storlie, Curt B. (Colorado State University, Fort Collins, CO)
Sampling-based methods for uncertainty and sensitivity analysis are reviewed. The following topics are considered: (1) Definition of probability distributions to characterize epistemic uncertainty in analysis inputs, (2) Generation of samples from uncertain analysis inputs, (3) Propagation of sampled inputs through an analysis, (4) Presentation of uncertainty analysis results, and (5) Determination of sensitivity analysis results. Special attention is given to the determination of sensitivity analysis results, with brief descriptions and illustrations given for the following procedures/techniques: examination of scatterplots, correlation analysis, regression analysis, partial correlation analysis, rank transformations, statistical tests for patterns based on gridding, entropy tests for patterns based on gridding, nonparametric regression analysis, squared rank differences/rank correlation coefficient test, two dimensional Kolmogorov-Smirnov test, tests for patterns based on distance measures, top down coefficient of concordance, and variance decomposition.
DNS of vertical plane channel flow with finite-size particles: Voronoi analysis, acceleration statistics and particle-conditioned averaging
Garcia-Villalba, Manuel; Uhlmann, Markus
We have performed a direct numerical simulation of dilute turbulent particulate flow in a vertical plane channel, fully resolving the phase interfaces. The flow conditions are the same as those in the main case of "Uhlmann, M., Phys. Fluids, vol. 20, 2008, 053305", with the exception of the computational domain length which has been doubled in the present study. The statistics of flow and particle motion are not significantly altered by the elongation of the domain. The large-scale columnar-like structures which had previously been identified do persist and they are still only marginally decorrelated in the prolonged domain. Voronoi analysis of the spatial particle distribution shows that the state of the dispersed phase can be characterized as slightly more ordered than random tending towards a homogeneous spatial distribution. It is also found that the p.d.f.'s of Lagrangian particle accelerations for wall-normal and spanwise directions follow a lognormal distribution as observed in previous experiments of ...
A Comprehensive Statistically-Based Method to Interpret Real-Time Flowing Measurements
Pinan Dawkrajai; Keita Yoshioka; Analis A. Romero; Ding Zhu; A.D. Hill; Larry W. Lake
This project is motivated by the increasing use of distributed temperature sensors for real-time monitoring of complex wells (horizontal, multilateral and multi-branching wells) to infer the profiles of oil, gas, and water entry. Measured information can be used to interpret flow profiles along the wellbore including junction and build section. In this second project year, we have completed a forward model to predict temperature and pressure profiles in complex wells. As a comprehensive temperature model, we have developed an analytical reservoir flow model which takes into account Joule-Thomson effects in the near well vicinity and multiphase non-isothermal producing wellbore model, and couples those models accounting mass and heat transfer between them. For further inferences such as water coning or gas evaporation, we will need a numerical non-isothermal reservoir simulator, and unlike existing (thermal recovery, geothermal) simulators, it should capture subtle temperature change occurring in a normal production. We will show the results from the analytical coupled model (analytical reservoir solution coupled with numerical multi-segment well model) to infer the anomalous temperature or pressure profiles under various conditions, and the preliminary results from the numerical coupled reservoir model which solves full matrix including wellbore grids. We applied Ramey's model to the build section and used an enthalpy balance to infer the temperature profile at the junction. The multilateral wellbore temperature model was applied to a wide range of cases varying fluid thermal properties, absolute values of temperature and pressure, geothermal gradients, flow rates from each lateral, and the trajectories of each build section.
Analysis of laser remote fusion cutting based on a mathematical model
Matti, R. S. [Department of Engineering Sciences and Mathematics, LuleÕ University of Technology, S-971 87 LuleÕ (Sweden); Department of Mechanical Engineering, College of Engineering, University of Mosul, Mosul (Iraq); Ilar, T.; Kaplan, A. F. H. [Department of Engineering Sciences and Mathematics, LuleÕ University of Technology, S-971 87 LuleÕ (Sweden)
Laser remote fusion cutting is analyzed by the aid of a semi-analytical mathematical model of the processing front. By local calculation of the energy balance between the absorbed laser beam and the heat losses, the three-dimensional vaporization front can be calculated. Based on an empirical model for the melt flow field, from a mass balance, the melt film and the melting front can be derived, however only in a simplified manner and for quasi-steady state conditions. Front waviness and multiple reflections are not modelled. The model enables to compare the similarities, differences, and limits between laser remote fusion cutting, laser remote ablation cutting, and even laser keyhole welding. In contrast to the upper part of the vaporization front, the major part only slightly varies with respect to heat flux, laser power density, absorptivity, and angle of front inclination. Statistical analysis shows that for high cutting speed, the domains of high laser power density contribute much more to the formation of the front than for low speed. The semi-analytical modelling approach offers flexibility to simplify part of the process physics while, for example, sophisticated modelling of the complex focused fibre-guided laser beam is taken into account to enable deeper analysis of the beam interaction. Mechanisms like recast layer generation, absorptivity at a wavy processing front, and melt film formation are studied too.
Oscillatory motion based measurement method and sensor for measuring wall shear stress due to fluid flow
Armstrong, William D. (Laramie, WY); Naughton, Jonathan (Laramie, WY); Lindberg, William R. (Laramie, WY)
A shear stress sensor for measuring fluid wall shear stress on a test surface is provided. The wall shear stress sensor is comprised of an active sensing surface and a sensor body. An elastic mechanism mounted between the active sensing surface and the sensor body allows movement between the active sensing surface and the sensor body. A driving mechanism forces the shear stress sensor to oscillate. A measuring mechanism measures displacement of the active sensing surface relative to the sensor body. The sensor may be operated under periodic excitation where changes in the nature of the fluid properties or the fluid flow over the sensor measurably changes the amplitude or phase of the motion of the active sensing surface, or changes the force and power required from a control system in order to maintain constant motion. The device may be operated under non-periodic excitation where changes in the nature of the fluid properties or the fluid flow over the sensor change the transient motion of the active sensor surface or change the force and power required from a control system to maintain a specified transient motion of the active sensor surface.
Poiseuille flow past a nanoscale cylinder in a slit channel: Lubrication theory versus molecular dynamics analysis
Amir M. Rahmani; Yang Shao; Mehlam Jupiterwala; Carlos E. Colosqui
Plane Poiseuille flow past a nanoscale cylinder that is arbitrarily confined (i.e., symmetrically or asymmetrically confined) in a slit channel is studied via hydrodynamic lubrication theory and molecular dynamics simulations, considering cases where the cylinder remains static or undergoes thermal motion. Lubrication theory predictions for the drag force and volumetric flow rate are in close agreement with molecular dynamics simulations of flows having molecularly thin lubrication gaps, despite the presence of significant structural forces induced by the crystalline structure of the modeled solid. While the maximum drag force is observed in symmetric confinement, i.e., when the cylinder is equidistant from both channel walls, the drag decays significantly as the cylinder moves away from the channel centerline and approaches a wall. Hence, significant reductions in the mean drag force on the cylinder and hydraulic resistance of the channel can be observed when thermal motion induces random off-center displacements. Analytical expressions and numerical results in this work provide useful insights into the hydrodynamics of colloidal solids and macromolecules in confinement.
Analysis of the flow imbalance on the profile shape during the extrusion of thin magnesium sheets
Gall, Sven [Forschungszentrum Strangpressen, Technische Universitõt Berlin, Gustav-Meyer-Allee 25, Berlin, 13355, Germany, and Metallische Werkstoffe, Technische Universitõt Berlin, Ernst-Reuter-Platz 1, Berlin, 10587 (Germany); M³ller, S÷ren [Forschungszentrum Strangpressen, Technische Universitõt Berlin, Gustav-Meyer-Allee 25, Berlin, 13355 (Germany); Reimers, Walter [Metallische Werkstoffe, Technische Universitõt Berlin, Ernst-Reuter-Platz 1, Berlin, 10587 (Germany)
The extrusion process facilitates the production of magnesium sheets featuring a very thin thickness as well as excellent surface properties by using a single process step only. However, the extrusion of the magnesium sheets applying not optimized process parameters, e.g. low billet temperature or/ and poorly deformable magnesium alloy, produce pronounced buckling and waving of the extruded sheets as well as a variation of accuracy in profile shape along the cross section. The present investigation focuses on the FEM-simulation of the extrusion of magnesium sheets in order to clarify the origin of the mentioned effects. The simulations identify the flow imbalance during extrusion as the main critical factor. Due to the flow imbalance after passing the die a large compression stress zone is formed causing the buckling and waving of the thin sheets. Furthermore, the simulations of the magnesium sheet extrusion reveal that the interaction of the material flow gradients along the width and along the thickness direction near the die orifice lead to the variation of the accuracy in profile shape.
Analysis of Granular Flow in a Pebble-Bed Nuclear Reactor
Chris H. Rycroft; Gary S. Grest; James W. Landry; Martin Z. Bazant
Pebble-bed nuclear reactor technology, which is currently being revived around the world, raises fundamental questions about dense granular flow in silos. A typical reactor core is composed of graphite fuel pebbles, which drain very slowly in a continuous refueling process. Pebble flow is poorly understood and not easily accessible to experiments, and yet it has a major impact on reactor physics. To address this problem, we perform full-scale, discrete-element simulations in realistic geometries, with up to 440,000 frictional, viscoelastic 6cm-diameter spheres draining in a cylindrical vessel of diameter 3.5m and height 10m with bottom funnels angled at 30 degrees or 60 degrees. We also simulate a bidisperse core with a dynamic central column of smaller graphite moderator pebbles and show that little mixing occurs down to a 1:2 diameter ratio. We analyze the mean velocity, diffusion and mixing, local ordering and porosity (from Voronoi volumes), the residence-time distribution, and the effects of wall friction and discuss implications for reactor design and the basic physics of granular flow.
Various sizes of sliding event bursts in the plastic flow of metallic glasses based on a spatiotemporal dynamic model
Ren, Jingli, E-mail: email@example.com, E-mail: firstname.lastname@example.com; Chen, Cun [School of Mathematics and Statistics, Zhengzhou University, Zhengzhou 450001 (China); Wang, Gang, E-mail: email@example.com, E-mail: firstname.lastname@example.com [Laboratory for Microstructures, Shanghai University, Shanghai 200444 (China); Cheung, Wing-Sum [Department of Mathematics, The University of HongKong, HongKong (China); Sun, Baoan; Mattern, Norbert [IFW-dresden, Institute for Complex Materials, P.O. Box 27 01 16, D-01171 Dresden (Germany); Siegmund, Stefan [Department of Mathematics, TU Dresden, D-01062 Dresden (Germany); Eckert, J³rgen [IFW-dresden, Institute for Complex Materials, P.O. Box 27 01 16, D-01171 Dresden (Germany); Institute of Materials Science, TU Dresden, D-01062 Dresden (Germany)
This paper presents a spatiotemporal dynamic model based on the interaction between multiple shear bands in the plastic flow of metallic glasses during compressive deformation. Various sizes of sliding events burst in the plastic deformation as the generation of different scales of shear branches occurred; microscopic creep events and delocalized sliding events were analyzed based on the established model. This paper discusses the spatially uniform solutions and traveling wave solution. The phase space of the spatially uniform system applied in this study reflected the chaotic state of the system at a lower strain rate. Moreover, numerical simulation showed that the microscopic creep events were manifested at a lower strain rate, whereas the delocalized sliding events were manifested at a higher strain rate.
Full field automated flow analysis of a spray using digital pulsed laser velocimetry
Delahunte, Katey Eileen
. . The MV image double B. The MV image double C. . Target grid for the EP doubles. . . Target grid for the EP singles. The EP image double 11. The EP image single 11. The EP image double 12. Page 35 36 36 39 40 41 42 43 44 45 47 47 48 51.... The EP image single 13. . The EP image double 14, The EP image single 14. Target grid for the analysis of EP doubles. Target grid for the analysis of EP singles. Region of EP double 11 used for analysis. Region of EP single 11 used for analysis...
Serrated flow behaviors of a Zr-based bulk metallic glass by nanoindentation
Cheng, L.; Jiao, Z. M.; Ma, S. G.; Wang, Z. H., E-mail: firstname.lastname@example.com, E-mail: firstname.lastname@example.com [Institute of Applied Mechanics and Biomedical Engineering, Taiyuan University of Technology, Taiyuan 030024 (China); Qiao, J. W., E-mail: email@example.com, E-mail: firstname.lastname@example.com [Institute of Applied Mechanics and Biomedical Engineering, Taiyuan University of Technology, Taiyuan 030024 (China); Laboratory of Applied Physics and Mechanics of Advanced Materials, College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024 (China)
Instrumented nanoindentation tests were used to investigate the mechanical properties of Zr{sub 52.5}Cu{sub 17.9}Ni{sub 14.6}Al{sub 10}Ti{sub 5} bulk metallic glass. The corresponding loading strain rates were ranged from 0.002?s{sup ?1}, 0.02?s{sup ?1} to 0.2?s{sup ?1}. Plastic flow of this material exhibited remarkable serrations at low strain rates and increasingly became weakening until disappearance with increasing indentation strain rate, implying strong rate sensitivity. A significant pile-up around the indents was observed through atomic force microscopy, which suggested a highly localized plastic deformation. Mechanism governing the deformation was tentatively discussed in terms of the increasing process of free volume with a negligible temperature rise under low strain rate, which well explained the declining trend of elastic modulus and hardness with an increase of indentation depth.
Feature-based Analysis of Plasma-based Particle Acceleration Data
Ruebel, Oliver; Geddes, Cameron G.R.; Chen, Min; Cormier-Michel, Estelle; Bethel, E. Wes
Plasma-based particle accelerators can produce and sustain thousands of times stronger acceleration fields than conventional particle accelerators, providing a potential solution to the problem of the growing size and cost of conventional particle accelerators. To facilitate scientific knowledge discovery from the ever growing collections of accelerator simulation data generated by accelerator physicists to investigate next-generation plasma-based particle accelerator designs, we describe a novel approach for automatic detection and classification of particle beams and beam substructures due to temporal differences in the acceleration process, here called acceleration features. The automatic feature detection in combination with a novel visualization tool for fast, intuitive, query-based exploration of acceleration features enables an effective top-down data exploration process, starting from a high-level, feature-based view down to the level of individual particles. We describe the application of our analysis in practice to analyze simulations of single pulse and dual and triple colliding pulse accelerator designs, and to study the formation and evolution of particle beams, to compare substructures of a beam and to investigate transverse particle loss.
PWR FLECHT SEASET 21-rod bundle flow blockage task data and analysis report. NRC/EPRI/Westinghouse Report No. 11. Appendices K-P
Loftus, M.J.; Hochreiter, L.E.; Lee, N.; McGuire, M.F.; Wenzel, A.H.; Valkovic, M.M.
This report presents data and limited analysis from the 21-Rod Bundle Flow Blockage Task of the Full-Length Emergency Cooling Heat Transfer Separate Effects and Systems Effects Test Program (FLECHT SEASET). The tests consisted of forced and gravity reflooding tests utilizing electrical heater rods with a cosine axial power profile to simulate PWR nuclear core fuel rod arrays. Steam cooling and hydraulic characteristics tests were also conducted. These tests were utilized to determine effects of various flow blockage configurations (shapes and distributions) on reflooding behavior, to aid in development/assessment of computational models in predicting reflooding behavior of flow blockage configurations, and to screen flow blockage configurations for future 163-rod flow blockage bundle tests.
Wang, Hai
RISK MANAGEMENT AND RISK ANALYSIS- BASED DECISION TOOLS FOR ATTACKS ON ELECTRIC POWER Simonoff, J.usc.edu/create Report #04-004DRAFT #12;Risk Management and Risk Analysis-Based Decision Tools for Attacks on Electric for Risk and Economic Analysis of Terrorism Events University of Southern California Los Angeles
A Conceptual Framework for Semantic Case-based Safety Analysis Olawande Daramola, Tor Stlhane
.firstname.lastname@example.com Abstract Hazard and Operability (HAZOP) Analysis and Fail- ure Mode and Effect Analysis (FMEA) are among-based framework for safety analy- sis, which facilitates the reuse of previous HAZOP and FMEA experiences in order application. Key words: Safety analysis, HAZOP, FMEA, ontology, requirements, case-based reasoning, natural
Flow induced vibration of a cantilever column jet: a spectral analysisĀ
Shilling, Roy Bryant
at where y = lateral displacement of the pipe, g = acceleration due to gravity, E*= viscoelastic modulus of elasticity Figure l A Cantilever Pipe Conveying a Fluid Flow 10 M( ? +U ? ) y6x a a /? qS6x F6x (c~ +~) 6x at t qS6x F6x aI') ~ T+ ? 6... MODEL MODEL Ii'fSTRUf&ENTAT I ON . TEST PIPE DIMiEI'ISIOiVLESS CRITICAL VELOCITY AffD FREQUENCY AS A FLiNCTION OF p DRIVING MECHANIS14 . RIGIDIFIER INSTRUMEflTATION SYSTEM NATLfRAL FREQUENCIES CANTILEVER RESPONSE DYNAMICS FORCED VIBPATION...
EIS-0163: 1992 Columbia River Salmon Flow Measures Options Analysis/EIS
Broader source: Energy.gov [DOE]
The U.S. Army Corps of Engineers ¢ Walla Walla District prepared this statement to analyze four general alternatives to modify the flow of water in the lower Columbia-Snake River in order to help anadromous fish migrate past eight multipurpose Federal dams. The U.S. Department of EnergyÆs Bonneville Power Administration served as a cooperating agency due to its key role in direct operation of the integrated and coordinated Columbia-Snake River System, and adopted this statement on February 10, 1992.
A comparison of an analytical and two electric analogy methods of hydraulic flow analysis
Hoffman, Joe Douglas
in available energy, The heat, Q, entering or leaving the system is also a loss of available mechanical energy from the system. Defining K , the increase in unavailable energy, as follows, EL-- (u2-ul) -Q, the energy balance now becomes V 2 V 2 Pl P2...=AV where Q is the volumetric rate of flow, and A is the cross sec- tional area of the pipe, Hence, A 2 x D Substituting this value of V, the following results. ~6. ) ~ ~. g), Defining k in the following manner ~6?(g(u) the relationship between...
Global helioseismic evidence for a deeply penetrating Solar meridional flow consisting of multiple flow cells
Schad, A; Roth, M
We use a novel global helioseismic analysis method to infer the meridional flow in the deep Solar interior. The method is based on the perturbation of eigenfunctions of Solar p modes due to meridional flow. We apply this method to time series obtained from Dopplergrams measured by the Michelson Doppler Imager aboard the Solar and Heliospheric Observatory (SOHO) covering the observation period 2004-2010. Our results show evidence that the meridional flow reaches down to the base of the convection zone. The flow profile has a complex spatial structure consisting of multiple flow cells distributed in depth and latitude. Toward the Solar surface, our results are in good agreement with flow measurements from local helioseismology.
Analysis of turbulent transport and mixing in transitional Rayleigh/Taylor unstable flow using direct numerical simulation data
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Schilling, Oleg; Mueschke, Nicholas J.
Data from a 1152X760X1280 direct numerical simulation (DNS) of a transitional Rayleigh-Taylor mixing layer modeled after a small Atwood number water channel experiment is used to comprehensively investigate the structure of mean and turbulent transport and mixing. The simulation had physical parameters and initial conditions approximating those in the experiment. The budgets of the mean vertical momentum, heavy-fluid mass fraction, turbulent kinetic energy, turbulent kinetic energy dissipation rate, heavy-fluid mass fraction variance, and heavy-fluid mass fraction variance dissipation rate equations are constructed using Reynolds averaging applied to the DNS data. The relative importance of mean and turbulent production, turbulent dissipationmoreĀ╗and destruction, and turbulent transport are investigated as a function of Reynolds number and across the mixing layer to provide insight into the flow dynamics not presently available from experiments. The analysis of the budgets supports the assumption for small Atwood number, Rayleigh/Taylor driven flows that the principal transport mechanisms are buoyancy production, turbulent production, turbulent dissipation, and turbulent diffusion (shear and mean field production are negligible). As the Reynolds number increases, the turbulent production in the turbulent kinetic energy dissipation rate equation becomes the dominant production term, while the buoyancy production plateaus. Distinctions between momentum and scalar transport are also noted, where the turbulent kinetic energy and its dissipation rate both grow in time and are peaked near the center plane of the mixing layer, while the heavy-fluid mass fraction variance and its dissipation rate initially grow and then begin to decrease as mixing progresses and reduces density fluctuations. All terms in the transport equations generally grow or decay, with no qualitative change in their profile, except for the pressure flux contribution to the total turbulent kinetic energy flux, which changes sign early in time (a countergradient effect). The production-to-dissipation ratios corresponding to the turbulent kinetic energy and heavy-fluid mass fraction variance are large and vary strongly at small evolution times, decrease with time, and nearly asymptote as the flow enters a self-similar regime. The late-time turbulent kinetic energy production-to-dissipation ratio is larger than observed in shear-driven turbulent flows. The order of magnitude estimates of the terms in the transport equations are shown to be consistent with the DNS at late-time, and also confirms both the dominant terms and their evolutionary behavior. These results are useful for identifying the dynamically important terms requiring closure, and assessing the accuracy of the predictions of Reynolds-averaged Navier-Stokes and large-eddy simulation models of turbulent transport and mixing in transitional Rayleigh-Taylor instability-generated flow.½Āless
Analysis of turbulent transport and mixing in transitional Rayleigh/Taylor unstable flow using direct numerical simulation data
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Schilling, Oleg [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); Mueschke, Nicholas J. [Texas A and M Univ., College Station, TX (United States)
Data from a 1152X760X1280 direct numerical simulation (DNS) of a transitional Rayleigh-Taylor mixing layer modeled after a small Atwood number water channel experiment is used to comprehensively investigate the structure of mean and turbulent transport and mixing. The simulation had physical parameters and initial conditions approximating those in the experiment. The budgets of the mean vertical momentum, heavy-fluid mass fraction, turbulent kinetic energy, turbulent kinetic energy dissipation rate, heavy-fluid mass fraction variance, and heavy-fluid mass fraction variance dissipation rate equations are constructed using Reynolds averaging applied to the DNS data. The relative importance of mean and turbulent production, turbulent dissipation and destruction, and turbulent transport are investigated as a function of Reynolds number and across the mixing layer to provide insight into the flow dynamics not presently available from experiments. The analysis of the budgets supports the assumption for small Atwood number, Rayleigh/Taylor driven flows that the principal transport mechanisms are buoyancy production, turbulent production, turbulent dissipation, and turbulent diffusion (shear and mean field production are negligible). As the Reynolds number increases, the turbulent production in the turbulent kinetic energy dissipation rate equation becomes the dominant production term, while the buoyancy production plateaus. Distinctions between momentum and scalar transport are also noted, where the turbulent kinetic energy and its dissipation rate both grow in time and are peaked near the center plane of the mixing layer, while the heavy-fluid mass fraction variance and its dissipation rate initially grow and then begin to decrease as mixing progresses and reduces density fluctuations. All terms in the transport equations generally grow or decay, with no qualitative change in their profile, except for the pressure flux contribution to the total turbulent kinetic energy flux, which changes sign early in time (a countergradient effect). The production-to-dissipation ratios corresponding to the turbulent kinetic energy and heavy-fluid mass fraction variance are large and vary strongly at small evolution times, decrease with time, and nearly asymptote as the flow enters a self-similar regime. The late-time turbulent kinetic energy production-to-dissipation ratio is larger than observed in shear-driven turbulent flows. The order of magnitude estimates of the terms in the transport equations are shown to be consistent with the DNS at late-time, and also confirms both the dominant terms and their evolutionary behavior. These results are useful for identifying the dynamically important terms requiring closure, and assessing the accuracy of the predictions of Reynolds-averaged Navier-Stokes and large-eddy simulation models of turbulent transport and mixing in transitional Rayleigh-Taylor instability-generated flow.
Thermally-driven flows between a Leidenfrost solid and a ratchet surface
Hardt, Steffen; Baier, Tobias
The significance of thermally-driven flows for the propulsion of Leidenfrost solids on a ratchet surface is studied based on a numerical solution of the Boltzmann equation. In contrast to a previous analysis, it is found that no significant thermal creep flow is established. Instead, the flow pattern is dominated by thermal edge and thermal-stress slip flow, the latter being directed opposite to thermal creep flow. However, in total thermally-induced flows only make a minor contribution to the propulsion of Leidenfrost solids on ratchet surfaces which is dominated by the pressure-driven flow due to the sublimating solid.
Analysis of Flow in Pilot Operated Safety and Relief Valve of Nuclear Reactor Coolant System
Kwon, Soon-Bum; Lee, Dong-Won [Department of Mechanical Engineering, Kyungpook National University, 1370, Sankyuk-dong, Daegu 702-701 (Korea, Republic of); Kim, In-Goo; Ahn, Hyung-Joon; Kim, Hho-Jung [Korea Institute of Nuclear Safety, 19, Kusungdong, Yousungku, Daejon 305-338 (Korea, Republic of)
When the POSRV equipped in a nuclear power plant opens in instant by a failure in coolant system of PWR, a moving shock wave generates, and propagates downstream of the valve, inducing a complicated unsteadiness. The moving shock wave may exert severe load to the structure. In this connection, a method of gradual opening of the valve is used to reduce the load acting on the wall at the downstream of the POSRV. In the present study, experiments and calculations are performed to investigate the detail unsteady flow at the various pipe units and the effect of valve opening time on the flow downstream of the valve. In calculation by using of air as working fluid, 2-dimensional, unsteady compressible Navier-Stokes equations are solved by finite volume method. It was found that when the incident shock wave passes through the pipe unit, it may experience diffraction, reflection and interaction with a vortex. Furthermore, the geometry of the pipe unit affects the reflection type of shock wave and changes the load acting on the wall of pipe unit. It was also turned out that the maximum force acting on the wall of the pipe unit becomes in order of T-junction, 108 deg. elbow and branch in magnitude, respectively. And, the results obtained that show that the rapid pressure rise due to the moving shock wave by instant POSRV valve opening is attenuated by employing the gradual opening. (authors)
Analysis of Fault Permeability Using Mapping and Flow Modeling, Hickory Sandstone Aquifer, Central Texas
Nieto Camargo, Jorge E., E-mail: email@example.com; Jensen, Jerry L., E-mail: firstname.lastname@example.com [University of Calgary, Department of Chemical and Petroleum Engineering (Canada)
Reservoir compartments, typical targets for infill well locations, are commonly created by faults that may reduce permeability. A narrow fault may consist of a complex assemblage of deformation elements that result in spatially variable and anisotropic permeabilities. We report on the permeability structure of a km-scale fault sampled through drilling a faulted siliciclastic aquifer in central Texas. Probe and whole-core permeabilities, serial CAT scans, and textural and structural data from the selected core samples are used to understand permeability structure of fault zones and develop predictive models of fault zone permeability. Using numerical flow simulation, it is possible to predict permeability anisotropy associated with faults and evaluate the effect of individual deformation elements in the overall permeability tensor. We found relationships between the permeability of the host rock and those of the highly deformed (HD) fault-elements according to the fault throw. The lateral continuity and predictable permeability of the HD fault elements enhance capability for estimating the effects of subseismic faulting on fluid flow in low-shale reservoirs.
Design, build and test of an axial flow hydrokinetic turbine with fatigue analysis
Ketcham, Jerod W
OpenProp is an open source propeller and turbine design and analysis code that has been in development since 2007 by MIT graduate students under the supervision of Professor Richard Kimball. In order to test the performance ...
Recession-based hydrological models for estimating low flows in ungauged catchments in the Himalayas Hydrology and Earth System Sciences, 8(5), 891902 (2004) EGU
Paris-Sud XI, Universit├® de
Recession-based hydrological models for estimating low flows in ungauged catchments in the Himalayas 891 Hydrology and Earth System Sciences, 8(5), 891902 (2004) ┬® EGU Recession-based hydrological.R. Young1 and S.R. Kansakar2 1 Centre for Ecology and Hydrology,Wallingford, Oxfordshire, OX10 8BB, UK 2
High temperature flow-through device for rapid solubilization and analysis
West, Jason A. A.; Hukari, Kyle W.; Patel, Kamlesh D.; Peterson, Kenneth A.; Renzi, Ronald F.
Devices and methods for thermally lysing of biological material, for example vegetative bacterial cells and bacterial spores, are provided. Hot solution methods for solubilizing bacterial spores are described. Systems for direct analysis are disclosed including thermal lysers coupled to sample preparation stations. Integrated systems capable of performing sample lysis, labeling and protein fingerprint analysis of biological material, for example, vegetative bacterial cells, bacterial spores and viruses are provided.
High temperature flow-through device for rapid solubilization and analysis
West, Jason A. A. (Castro Valley, CA); Hukari, Kyle W. (San Ramon, CA); Patel, Kamlesh D. (Dublin, CA); Peterson, Kenneth A. (Albuquerque, NM); Renzi, Ronald F. (Tracy, CA)
Devices and methods for thermally lysing of biological material, for example vegetative bacterial cells and bacterial spores, are provided. Hot solution methods for solubilizing bacterial spores are described. Systems for direct analysis are disclosed including thermal lysers coupled to sample preparation stations. Integrated systems capable of performing sample lysis, labeling and protein fingerprint analysis of biological material, for example, vegetative bacterial cells, bacterial spores and viruses are provided.
Kandlikar, Satish
. (2004) developed three- zone flow boiling heat transfer model to describe evaporation of elongated
Transportation Analysis, Modeling, and Simulation (TAMS) Application
Transportation Analysis, Modeling, and Simulation (TAMS) Application Center for Transportation Passenger Flows Supply Chain Efficiency Transportation: Energy Environment Safety Security Vehicle Technologies T he Center for Transportation Analysis (CTA) TAMS application is a web-based tool that supports
Validation Analysis of the Groundwater Flow and Transport Model of the Central Nevada Test Area
A. Hassan; J. Chapman; H. Bekhit; B. Lyles; K. Pohlmann
The Central Nevada Test Area (CNTA) is a U.S. Department of Energy (DOE) site undergoing environmental restoration. The CNTA is located about 95 km northeast of Tonopah, Nevada, and 175 km southwest of Ely, Nevada (Figure 1.1). It was the site of the Faultless underground nuclear test conducted by the U.S. Atomic Energy Commission (DOE's predecessor agency) in January 1968. The purposes of this test were to gauge the seismic effects of a relatively large, high-yield detonation completed in Hot Creek Valley (outside the Nevada Test Site [NTS]) and to determine the suitability of the site for future large detonations. The yield of the Faultless underground nuclear test was between 200 kilotons and 1 megaton (DOE, 2000). A three-dimensional flow and transport model was created for the CNTA site (Pohlmann et al., 1999) and determined acceptable by DOE and the Nevada Division of Environmental Protection (NDEP) for predicting contaminant boundaries for the site.
Suppressing Riser-Based Slugging in Multiphase Flow by State Feedback
Foss, Bjarne A.
of the system, x1 is the total mass of gas in the volume upstream of the riser base (volume one), x2 is the total mass of gas in the riser (volum or vertical pipe sections, and is potentially damaging to downstream processing equipment such as separators
A Multi-Commodity Flow Approach to Maximising Utility in Linked Market-Based Grids
Melbourne, University of
. We then obtain a utility-aware distributed algorithm that generates increased utility utility in linked market-driven distributed and Grid systems. In such sys- tems, users submit jobs through-based, utility driven distributed systems, where all participants selfishly attempt to max- imise their own gain
A Flow Level Perspective on Base Station Power Allocation in Green Networks
Boyer, Edmond
the energy-efficiency of base stations operating in the downlink. The energy-efficiency refers to the amount nature of users (referred to as the global energy-efficiency). We emphasize our numerical results that study the influence of the radio conditions, transmit power and the user traffic on the energy-efficiency
Analysis of fluid flow and heat transfer in a rib grit roughened surface solar air heater using CFD
Karmare, S.V. [Department of Mechanical Engineering, Government College Engineering, Karad 415 124, Maharashtra (India); Shivaji University, Kolhapur, Maharashtra (India); Tikekar, A.N. [Department of Mechanical Engineering, Walchand College of Engineering, Sangli (India); Shivaji University, Kolhapur, Maharashtra (India)
This paper presents the study of fluid flow and heat transfer in a solar air heater by using Computational Fluid Dynamics (CFD) which reduces time and cost. Lower side of collector plate is made rough with metal ribs of circular, square and triangular cross-section, having 60 inclinations to the air flow. The grit rib elements are fixed on the surface in staggered manner to form defined grid. The system and operating parameters studied are: e/D{sub h} = 0.044, p/e = 17.5 and l/s = 1.72, for the Reynolds number range 3600-17,000. To validate CFD results, experimental investigations were carried out in the laboratory. It is found that experimental and CFD analysis results give the good agreement. The optimization of rib geometry and its angle of attack is also done. The square cross-section ribs with 58 angle of attack give maximum heat transfer. The percentage enhancement in the heat transfer for square plate over smooth surface is 30%. (author)
Analysis of reactor material experiments investigating corium crust stability and heat transfer in jet impingement flow
Sienicki, J.J.; Spencer, B.W.
Presented is an analysis of the results of the CSTI-1, CSTI-3, and CWTI-11 reactor material experiments in which a jet of molten corium initially at 3080/sup 0/K was directed downward upon a stainless steel plate. The experiments are a continuation of a program of reactor material tests investigating LWR severe accident phenomena. Objective of the present analysis is to determine the existence or nonexistence of a corium crust during impingement from comparison of the measured heatup of the plate (as measured by thermocouples imbedded immediately beneath the steel surface) with model calculations assuming alternately the presence and absence of a stable crust during impingement.
Seepage flow-stability analysis of the riverbank of Saigon river due to river water level fluctuation
Oya, A; Hiraoka, N; Fujimoto, M; Fukagawa, R
The Saigon River, which flows through the center of Ho Chi Minh City, is of critical importance for the development of the city as forms as the main water supply and drainage channel for the city. In recent years, riverbank erosion and failures have become more frequent along the Saigon River, causing flooding and damage to infrastructures near the river. A field investigation and numerical study has been undertaken by our research group to identify factors affecting the riverbank failure. In this paper, field investigation results obtained from multiple investigation points on the Saigon River are presented, followed by a comprehensive coupled finite element analysis of riverbank stability when subjected to river water level fluctuations. The river water level fluctuation has been identified as one of the main factors affecting the riverbank failure, i.e. removal of the balancing hydraulic forces acting on the riverbank during water drawdown.
Panorama: Capturing System-wide Information Flow for Malware Detection and Analysis
Kruegel, Christopher
breaching users' privacy (including keyloggers, pass- word thieves, network sniffers, stealth backdoors to remote servers in certain settings. We believe that a system such This material is based upon work
automated voxel-based analysis: Topics by E-print Network
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Approach to Sensor Selection- prehensive automated Failure Modes and Effects Analysis (FMEA) using qualitative model based reasoning au- tonomous aircraft. Automated failure mode...
Under consideration for publication in J. Functional Programming 1 Noninterference through Flow Analysis
Gay, Simon
Analysis Kohei Honda Queen Mary, London Nobuko Yoshida Imperial College London Abstract This paper proposes Extensions (1): In ation and Branching 30 6.1 In ation 30 6.2 Branching and Selection 31 #12; 2 K. Honda (Berger et al. 01; Yoshida et al. 01; Yoshida et al. 02; Honda and Yoshida 02; Honda et al. 04), whose
Parallel-Flow-Shear Driven Low-Frequency Plasma Instability
Ishiguro, Seiji [Theory and Computer Simulation Center, National Institute for Fusion Science, Toki-shi, Gifu 509-5292 (Japan); Matsumoto, Noriaki; Kaneko, Toshiro; Hatakeyama, Rikizo [Department of Electronic Engineering, Tohoku University, Sendai 980-8579 (Japan)
Full three dimensional Particle-in-Cell (PIC) simulations are performed in order to investigate effects of field-aligned (parallel) ion flow shears on low-frequency plasma instabilities. It is shown that the parallel ion flow velocity shear can induce the ion-acoustic instability, even when the ion flow velocity is so small that the instability can not take place. Simulation results are consistent with the analysis based on the local theory.
Building Energy Performance Analysis of an Academic Building Using IFC BIM-Based MethodologyĀ
Aziz, Z.; Arayici, Y.; Shivachev, D.
This paper discusses the potential to use an Industry Foundation Classes (IFC)/Building Information Modelling (BIM) based method to undertake Building Energy Performance analysis of an academic building. BIM/IFC based methodology provides a...
Exploring potential R&D collaboration partners through patent analysis based on bibliographic coupling and latent semantic analysis
Park, I.; Jeong, Y.; Yoon, B.; Mortara, L.
on the citation relationship using patent bibliographic information. Second, latent semantic analysis is utilized based on semantic similarity using patent textual information. The fuel cell membrane electrode assembly (MEA) technology field is selected...
A new flow field design for polymer electrolyte-based fuel cells C. Xu, T.S. Zhao *
Zhao, Tianshou
the concentration polarization. They also found that liquid water accumulated more rap- idly under channel ribs between adjacent flow channels over the entire electrode surface than does the conventional flow field cell; Water flooding; Flow field; Under-rib convection 1. Introduction Polymer electrolyte membrane
Debris-flow runout predictions based on the average channel slope (ACS) Adam B. Prochaska a,, Paul M. Santi a
distance of a debris flow is an important element in the delineation of potentially hazardous areas for the delineation of potentially hazardous areas on alluvial fans and for the siting of mitigation structures: Debris flow; Runout; Hazard mapping 1. Introduction Debris-flow runout estimations are important
Analysis of a multiphase, porous-flow imbibition experiment in fractured volcanic tuff
Eaton, R.R.; Bixler, N.E.
A sub-meter-scale imbibition experiment has been analyzed using a finite element, multiphase-flow code. In the experiment, an initially dry cylindrical core of fractured volcanic tuff was saturated by contacting the ends with pressurized water. Our model discretely accounts for three primary fractures that may be present in the core, as indicated by measurements of porosity and saturation. We show that vapor transport has a small (less than 5%) effect on the speed of the wetting front. By using experimental results to estimate apparent spatial variations in permeability along the core, good agreement with measured, transient, saturation data was achieved. The sensitivity of predicted transient wetting fronts to permeability data indicates a need for more extensive measurements. We conclude that it will be difficult to characterize an entire repository - where inhomogeneities due to variations in matrix and fracture properties are not well known - solely from the results of sub-meter-scale laboratory testing and deterministic modeling. 16 refs., 8 figs., 1 tab.
Drying analysis of a multiphase, porous-flow experiment in fractured volcanic tuff
Bixler, N.E.; Eaton, R.R.; Russo, A.J.
A submeter-scale drying experiment has been analyzed using a finite element, multiphase-flow code. In the experiment, an initially wet cylindrical core of fractured volcanic tuff was dried by blowing dry nitrogen over the ends. Our model discretely accounts for three primary fractures that may be present in the core, as indicated by measurements of porosity and saturation. We show that vapor transport is unimportant in the interior of the core; the rate of drying is controlled by transport of liquid water to the ends of the core, where it can evaporate and escape into the dry environment outside. By using previous experimental results to estimate apparent spatial variations in permeability along the core, good agreement between measured and calculated drying rates was achieved. However, predicted saturation profiles were much smoother that those measured experimentally, presumably because of centimeter-scale inhomogeneities in the core sample. Our results indicate that water is transported chiefly as liquid from the interior to the edges of the core, where it evaporates and escapes out the ends. Thus, liquid-phase transport controls the overall drying rate. 18 refs., 8 figs., 1 tab.
Higher-order compositional modeling of three-phase flow in 3D fractured porous media based on cross-flow equilibrium
Firoozabadi, Abbas
to approximate convective Darcy fluxes and the pressure equa- tion. This approach is the most natural choice for flow in fractured media. The mass balance equations are discretized by the discontinuous Galerkin (DG injection in oil reservoirs that have previously been water flooded. Another example is when gas is injected
Towards Adaptable Control Flow Segmentation for Measurement-Based Execution Time Analysis
. An airbag not releasing in time or a non-reacting aircraft control unit for instance can lead to a fatal
Near-Infrared Detection of Flow Injection Analysis by Acoustooptic Tunable Filter-Based
Reid, Scott A.
pretreatment), and the availability of powerful and effective multivariate statistical methods for data wavelength. As a consequence, the multivariate calibration methods cannot be used to analyze data
Knowledge-base for the new human reliability analysis method, A Technique for Human Error Analysis (ATHEANA)
Cooper, S.E. [Science Application International Corp., Reston, VA (United States); Wreathall, J. [John Wreathall & Co., Dublin, OH (United States); Thompson, C.M., Drouin, M. [Nuclear Regulatory Commission, Washington, DC (United States); Bley, D.C. [Buttonwood Consulting, Inc., Oakton, VA (United States)
This paper describes the knowledge base for the application of the new human reliability analysis (HRA) method, a ``A Technique for Human Error Analysis`` (ATHEANA). Since application of ATHEANA requires the identification of previously unmodeled human failure events, especially errors of commission, and associated error-forcing contexts (i.e., combinations of plant conditions and performance shaping factors), this knowledge base is an essential aid for the HRA analyst.
Three-dimensional analysis of future groundwater flow conditions and contaminant plume transport in the Hanford Site unconfined aquifer system: FY 1996 and 1997 status report
Cole, C.R.; Wurstner, S.K.; Williams, M.D.; Thorne, P.D.; Bergeron, M.P.
A three-dimensional numerical model of groundwater flow and transport, based on the Coupled Fluid Energy, and Solute Transport (CFEST) code, was developed for the Hanford Site to support the Hanford Groundwater Project (HGWP), managed by Pacific Northwest National Laboratory. The model was developed to increase the understanding and better forecast the migration of several contaminant plumes being monitored by the HGWP, and to support the Hanford Site Composite Analysis for low-level waste disposal in the 200-Area Plateau. Recent modeling efforts have focused on continued refinement of an initial version of the three-dimensional model developed in 1995 and its application to simulate future transport of selected contaminant plumes in the aquifer system. This version of the model was updated using a more current version of the CFEST code called CFEST96. Prior to conducting simulations of contaminant transport with the three-dimensional model, a previous steady-state, two-dimensional model of the unconfined aquifer system was recalibrated to 1979 water-table conditions with a statistical inverse method implemented in the CFEST-INV computer code. The results of the recalibration were used to refine the three-dimensional conceptual model and to calibrate it with a conceptualization that preserves the two-dimensional hydraulic properties and knowledge of the aquifer`s three-dimensional properties for the same 1979 water-table conditions. The transient behavior of the three-dimensional flow model was also calibrated by adjusting model storage properties (specific yield) until transient water-table predictions approximated observed water-table elevations between 1979 and 1996.
Analysis of Flow of Control for Reverse Engineering of Sequence Diagrams
Rountev, Atanas "Nasko"
of The Ohio State University By Olga Nicole Volgin, B.S. * * * * * The Ohio State University 2005 Master and Information Science #12;ABSTRACT During software lifecycle, the design documentation and implementation often enhancement based on inaccurate documentation may result in costly software design and implementation flaws
Flow injection analysis of phenolic compounds with carbon paste electrodes modified with tyrosinase purchased from different companies
Lindgren, A.; Emneus, J.; Csoeregi, E.; Gorton, L.; Marko-Varga, G. [Univ. of Lund (Sweden); Ruzgas, T. [Inst. of Biochemistry, Vilnius (Lithuania)
Tyrosinase-modified carbon paste electrodes were prepared using lyophilised powder of the enzyme purchased from different companies. The selectivity of these electrodes for nine phenolic compounds, including six substituted catechols, has been studied. The signals obtained for catechol were always higher than those found for other phenolic compounds. Cyclic voltammetry and flow injection measurements indicated that the response of the tyrosinase-modified carbon paste electrodes was limited by the rate of the enzymatic oxidation of catechols. Different approaches of past electrode preparation have been studied and compared. Direct mixing of enzyme into the graphite powder doped with the osmium based mediator, resulted in the highest sensitivity for the studied substrates. However, substrate selectivity was found to be dependent on the source of enzyme used for electrode preparation.
Geographically-Based Hydrogen Demand & Infrastructure Rollout Scenario Analysis (Presentation)
Melendez, M.
This presentation by Margo Melendez at the 2007 DOE Hydrogen Program Annual Merit Review Meeting provides information about NREL's Hydrogen Demand & Infrastructure Rollout Scenario Analysis.
Tariff-based analysis of commercial building electricity prices
Coughlin, Katie M.; Bolduc, Chris A.; Rosenquist, Greg J.; Van Buskirk, Robert D.; McMahon, James E.
this analysis. For the energy consumption data, within eachenergy consumption, for January and July, for the CBECS data. . . . . . . . . . . . . . . . . . . . . . . . . . . . .4]. The billing data include energy consumption, demand and
analysis methodology based: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
...9 1.3.2 Full 3D TomographyA UNIFIED METHODOLOGY FOR SEISMIC WAVEFORM ANALYSIS AND INVERSION by Po Chen A Dissertation program for tomgraphic...
Analysis of Heat Transfer in Metal Hydride Based Hydrogen Separation
Fleming, W.H. Jr.
This thesis presents a transient heat transfer analysis to model the heat transfer in the Pd/k packed column, and the impact of adding metallic foam.
An analog analysis of transient heat flow in solids with temperature-dependent thermal properties
Lee, Dwain Edward
they both are based on the same approximation of the thermal properties. Since these two methods of solution of the same problem produce almost the same results, the usefulness of the constant property analog method of solution must be found elsewhere... calculations. Therefore, it is concluded that the better the approximation of the variation of the thermal properties allowed by a method of solution, the more closely that method of solution will agree with the actual physical problem. In particular...
A Novel Wavelet Transform Based Transient Current Analysis for Fault Detectionand Localization *
Bhunia, Swarup
25.2 A Novel Wavelet Transform Based Transient Current Analysis for Fault Detectionand Localization. In this paper, we present a novel integrated method for fault detection and localization using wavelet transform based IDD waveform analysis. The time-frequency resolu- tion property of wavelet transform helps us
Formal Analysis and Validation of Continuous-Time Markov Chain based System Level Power Management Strategies
Oxford, University of
Formal Analysis and Validation of Continuous-Time Markov Chain based System Level Power Management that competitive analysis based power management strategies can be automatically analyzed for proving competitive bounds and for validating power management strate- gies using the SMV model checker. In this paper, we
Formal Analysis and Validation of ContinuousTime Markov Chain based System Level Power Management Strategies
Oxford, University of
Formal Analysis and Validation of ContinuousŁTime Markov Chain based System Level Power Management that competitive analysis based power management strategies can be automatically analyzed for proving competitive bounds and for validating power management strateŁ gies using the SMV model checker. In this paper, we
Computeer-based decision support tools for evaluation of actions affecting flow and water quality in the San Joaquin Basin
Quinn, N.W.T.
This document is a preliminary effort to draw together some of the important simulation models that are available to Reclamation or that have been developed by Reclamation since 1987. This document has also attempted to lay out a framework by which these models might be used both for the purposes for which they were originally intended and to support the analysis of other issues that relate to the hydrology and to salt and water quality management within the San Joaquin Valley. To be successful as components of a larger Decision Support System the models should to be linked together using custom designed interfaces that permit data sharing between models and that are easy to use. Several initiatives are currently underway within Reclamation to develop GIS - based and graphics - based decision support systems to improve the general level of understanding of the models currently in use, to standardize the methodology used in making planning and operations studies and to permit improved data analysis, interpretation and display. The decision support systems should allow greater participation in the planning process, allow the analysis of innovative actions that are currently difficult to study with present models and should lead to better integrated and more comprehensive plans and policy decisions in future years.
Flow instabilities in the core and the coolant circuit of advances low-boiling light water reacto: classification of causes and development of simulator for the future analysis
Rezvyi, Aleksey
. . 1. 3. Analysis method determination. 2. THEORETICAL ASPECTS OF DIFFERENT TYPES OF THE THERMO-HYDRAULIC INSTABILITIES. . 2. 1. Static instability of loading charactenstic. . . . . . . . . . . . . . . . . . . . . . . 2. 2. Resonance instability... in the 1C L-BWR during heat-up process. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Diagram of components hierarchy of the Thermo-Hydraulic instabilities phenomenon. . The steam generating heating channels instability area, mass flow vs...
Improving the Accuracy of Software-Based Energy Analysis for Residential Buildings (Presentation)
Polly, B.
This presentation describes the basic components of software-based energy analysis for residential buildings, explores the concepts of 'error' and 'accuracy' when analysis predictions are compared to measured data, and explains how NREL is working to continuously improve the accuracy of energy analysis methods.
Alternatives to Energy FunctionBased Analysis of Recurrent Neural Networks
Hassoun, Mohamad H.
1 Alternatives to Energy FunctionŁBased Analysis of Recurrent Neural Networks Mohamad H. Hassoun of analysis and design of recurrent neural networks using an energy function approach, as popularized, 1990]. Such type of analysis, though, usually imposes stringent and/or biologically unrealistic
of Transportation Rigid Pavement Design and Analysis Web-Based Training Site
Texas at Austin, University of
Texas Department of Transportation Rigid Pavement Design and Analysis Web-Based Training Site Highway Administration Texas Department of Transportation, 2004 Rigid Pavement Design and Analysis Web for six computer programs pertaining mainly to the design and analysis of rigid pavements. The programs
A network-based modeling framework for stakeholder analysis of China's energy conservation campaign
de Weck, Olivier L.
A network-based modeling framework for stakeholder analysis of China's energy conservation campaign Available online 13 July 2011 Keywords: Energy conservation Policy-making Stakeholder analysis Network, the stakeholder analysis of China's energy conservation campaign still has been under-developed. This paper
Spatial and temporal analysis and experiments of annular two-phase flow under microgravity conditions
Carron, Igor
of the coexistence of huge waves with liquid slugs. This last observation however is already too detailed for the codes that are developed nowadays for nuclear safety assessment such as RELAP 5 [6). One of the main issue is therefore to characterize quantitatively... and base state II. 5 Verification of the code II. 6 Implementation . . II. 7 Conclusion 17 18 20 30 34 40 45 EXPERIMENTS IN A REDI. CED GRAVITY ENVIRONMENT . . III. l Experiments carried out at Texas A@i%'I University III. 2 The 1986 experiment...
Shape-based Cost Analysis of Skeletal Parallel ProgramsĀ
Hayashi, Yasushi
This work presents an automatic cost-analysis system for an implicitly parallel skeletal programming language. Although deducing interesting dynamic characteristics of parallel programs (and in particular, run time) is ...
LOSS OF COOLANT ACCIDENT AND LOSS OF FLOW ACCIDENT ANALYSIS OF THE ARIES-AT DESIGN E. A. Mogahed, L. El-Guebaly, A. Abdou, P. Wilson, D. Henderson and the ARIES Team
California at San Diego, University of
LOSS OF COOLANT ACCIDENT AND LOSS OF FLOW ACCIDENT ANALYSIS OF THE ARIES-AT DESIGN E. A. Mogahed, L accident (LOCA) and loss of flow accident (LOFA) analysis is performed for ARIES-AT, an advanced fusion of steel in the reactor is about (600 ┬░C - 700┬░C) after about 4 days from the onset of the accident
Object-Oriented Modelling and Simulation of Air Flow in Data Centres Based on a Quasi-3D Approach for Energy Optimisation
Como, Giacomo
Ł5]. On the other hand, power delivery, electricity consumption, and heat management studies for data centre) simulation is extensively used for simulate airflow and heating components in data centres. CFD modellingObject-Oriented Modelling and Simulation of Air Flow in Data Centres Based on a Quasi-3D Approach
analysis system based: Topics by E-print Network
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energy consumption and component stresses and instabilities. 1. FOREWORDS The micro-gas turbine based energy conversion systems represent one of the most recently developed...
Analysis of Refrigerant Flow and Deformation for a Flexible Short-Tube using a Finite Element Model
O'Neal, D.L.; Bassiouny, R.
reliability. Short-tubes have either a constant inner dia- meter flow channel or a tapered channel with a smallAbstract A finite element model was used to simulate single-phase flow of R-22 through flexible short-tubes. The numerical model included the fluid... in the flow area. The more flexible (5513 kPa) short-tube restricted the mass flow rate more than the most rigid (9889 kPa) short-tube used in this study. The mass flow rates estimated with the finite element model were as much as 14% higher than those from...
Building Information Modeling (BIM)-Based Daylighting Simulation and AnalysisĀ
Kota, S.; Haberl, J.S.; Clayton, M.; Yan, W.
will be converted into daylighting models to run on the daylighting simulation engines. Once the architect defines the architectural model in CAD, a simulation expert creates the simulation input file to perform daylighting analysis. Each tool has its own way... the Radiance input file is created, different Radiance utilities are called using MS Windows BATCH scripting for doing a daylighting analysis [15]. In addition to AutoCAD, Radiance also has many utility programs that help in converting different geometry...
Building Information Modeling (BIM)-Based Daylighting Simulation and Analysis
Kota, S.; Haberl, J.S.; Clayton, M.; Yan, W.
tools Radiance and DAYSIM. Keywords: Building Information Modeling, BIM, Daylighting Simulation, Radiance, DAYSIM 1 Introduction Building performance analyses are important aspects of designing sustainable buildings. One of the performance analyses...) with daylighting analysis tools (Radiance and DAYSIM as sample simulation tools, which are widely used to study the daylighting performance of buildings). 2 Literature review 2.1 Daylighting simulation tools Over the years many analysis tools have been...
Dealing with big circulation flow, small temperature difference based on verified dynamic model simulations of a hot water district heating system
Zhong, L.
DEALING WITH ōBIG CIRCULATION FLOW RATE, SMALL TEMPERATURE DIFFERENCEö BASED ON VERIFIED DYNAMIC MODEL SIMULATIONS OF A HOT WATER DISTRICT HEATING SYSTEM Li Lian Zhong, Senior Sales Consultant, Danfoss Automatic Controls Management (Shanghai...) Co.,Ltd, Anshan, China ABSTRACT Dynamic models of an indirect hot water district heating system were developed based on the first principle of thermodynamics. The ideal model was verified by using measured operational data. The ideal...
Performance analysis of a D-sequence based Direct Sequence CDMA system
Koppelman, David M.
Performance analysis of a D-sequence based Direct Sequence CDMA system S. Herlekar and S. Kak The performance of a D-sequence based Direct Sequence CDMA system over an additive white Gaussian noise (AWGN) channel is analyzed. The results indicate a superior performance for this system over a PN sequence based
Comparison of MRI-based and CT/MRI fusion-based postimplant dosimetric analysis of prostate brachytherapy
Tanaka, Osamu [Department of Radiology, Gifu University School of Medicine, Gifu City (Japan)]. E-mail: firstname.lastname@example.com; Hayashi, Shinya [Department of Radiology, Gifu University School of Medicine, Gifu City (Japan); Matsuo, Masayuki [Department of Radiology, Gifu University School of Medicine, Gifu City (Japan); Sakurai, Kota [Department of Radiology, Gifu University School of Medicine, Gifu City (Japan); Department of Urology, Gifu University School of Medicine, Gifu City (Japan); Nakano, Masahiro [Department of Urology, Gifu University School of Medicine, Gifu City (Japan); Maeda, Sunaho [Department of Radiology, Gifu University School of Medicine, Gifu City (Japan); Kajita, Kimihiro R.T. [Department of Radiology, Gifu University School of Medicine, Gifu City (Japan); Deguchi, Takashi [Department of Urology, Gifu University School of Medicine, Gifu City (Japan); Hoshi, Hiroaki [Department of Radiology, Gifu University School of Medicine, Gifu City (Japan)
Purpose: The aim of this study was to compare the outcomes between magnetic resonance imaging (MRI)-based and computed tomography (CT)/MRI fusion-based postimplant dosimetry methods in permanent prostate brachytherapy. Methods and Materials: Between October 2004 and March 2006, a total of 52 consecutive patients with prostate cancer were treated by brachytherapy, and postimplant dosimetry was performed using CT/MRI fusion. The accuracy and reproducibility were prospectively compared between MRI-based dosimetry and CT/MRI fusion-based dosimetry based on the dose-volume histogram (DVH) related parameters as recommended by the American Brachytherapy Society. Results: The prostate volume was 15.97 {+-} 6.17 cc (mean {+-} SD) in MRI-based dosimetry, and 15.97 {+-} 6.02 cc in CT/MRI fusion-based dosimetry without statistical difference. The prostate V100 was 94.5% and 93.0% in MRI-based and CT/MRI fusion-based dosimetry, respectively, and the difference was statistically significant (p = 0.002). The prostate D90 was 119.4% and 114.4% in MRI-based and CT/MRI fusion-based dosimetry, respectively, and the difference was statistically significant (p = 0.004). Conclusion: Our current results suggested that, as with fusion images, MR images allowed accurate contouring of the organs, but they tended to overestimate the analysis of postimplant dosimetry in comparison to CT/MRI fusion images. Although this MRI-based dosimetric discrepancy was negligible, MRI-based dosimetry was acceptable and reproducible in comparison to CT-based dosimetry, because the difference between MRI-based and CT/MRI fusion-based results was smaller than that between CT-based and CT/MRI fusion-based results as previously reported.
Ekechukwu, A
The most common method of analysis for beryllium is inductively coupled plasma atomic emission spectrometry (ICP-AES). This method, along with inductively coupled plasma mass spectrometry (ICP-MS), is discussed in Chapter 6. However, other methods exist and have been used for different applications. These methods include spectroscopic, chromatographic, colorimetric, and electrochemical. This chapter provides an overview of beryllium analysis methods other than plasma spectrometry (inductively coupled plasma atomic emission spectrometry or mass spectrometry). The basic methods, detection limits and interferences are described. Specific applications from the literature are also presented.
Analysis of Energy Efficiency Program Impacts Based on Program Spending -
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041cloth DocumentationProductsAlternative FuelsSanta FeAuthorization|EnergyAnalysis ofAnalysis
Expeditious Data Center Sustainability, Flow, and Temperature Modeling: Life-Cycle Exergy Consumption Combined with a Potential Flow Based, Rankine Vortex Superposed, Predictive Method
Lettieri, David
Methodology iii Life-Cycle Assessment (LCA) . . . . . . .Results 6.1 Life-Cycle Assessment (LCA) . . . . . 6.1.1Analysis (LCEA) 4. Life-Cycle Assessment (LCA) 5. Exergetic
Tariff-based analysis of commercial building electricity prices
Coughlin, Katie M.; Bolduc, Chris A.; Rosenquist, Greg J.; Van Buskirk, Robert D.; McMahon, James E.
LBNL-55551 EIA-based average revenues by sales (in c/kWh)in region R of ownership type P (from EIA data) Set of allutilities in region R (from EIA data) Set of sample
Security Analysis and Improvement Model for Web-based Applications
Wang, Yong
, confidentiality, and data integrity. According to the reports from http://www.securityfocus.com in May 2006, operating systems account for 9% vulnerability, web-based software systems account for 61% vulnerability, and other applications account for 30...
An Analysis of TRL-Based Cost and Schedule Models
Kenley, C. Robert
The GAO's, NASA's, and the DoD's adoption of the technology readiness level (TRL) scale to improve technology management has led to the emergence of many TRL-based models that are used to monitor technology maturation, ...
Analysis of reactor material experiments investigating oxide fuel crust stability and heat transfer in jet impingement flow
Sienicki, J.J.; Spencer, B.W.
An analysis is presented of the crust stability and heat transfer behavior in the CSTI-1, CSTI-3, and CWTI-11 reactor material experiments in which a jet of molten oxide fuel at approx. 160/sup 0/K above its freezing temperature was impinged normally upon stainless steel plates initially at 300 and 385 K. The major issue is the existence of nonexistence of a stable solidified layer of fuel, or crust, interstitial to the flowing hot fuel and the steel substrate, tending to insulate the steel from the hot molten fuel. A computer model was developed to predict the heatup of thermocouples imbedded immediately beneath the surface of the plate for both of the cases in which a stable crust is assumed to be either present or absent during the impingement phase. Comparison of the model calculations with the measured thermocouple temperatures indicates that a protective crust was present over nearly all of the plate surface area throughout the impingement process precluding major melting of the plate steel. However, the experiments also show evidence for very localized and isolated steel melting as revealed by localized and isolated pitting of the steel surface and the response of thermocouples located within the pitted region.
annular vertical flow: Topics by E-print Network
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of the polymer solution only. The linear stability analysis of the flow in the short-wave approximation captures quantitatively the flow diagram. Surprisingly, unstable flows...
Abstract--This work develops a three-phase unbalanced load flow tool tailored for radial distribution networks based
Teodorescu, Remus
support by PV inverters can be also merged together with the load flow solution tool and thus, the impact, thermal limits of grid components and power losses in radial MV-LV networks with photovoltaic (PV and validated with IEEE 13-bus test feeder. Index Terms--Load flow, LV network, PV integration, voltage
HMM-based neural spike analysis Michael C. Nechyba
Slatton, Clint
┬Ę Generating training data ┬Ę Results ┬Ę Current/future work #12;Classifier block diagram s O Ot N┬Ł 1+ Ot N┬Ł 2+ Ot 1┬Ł Ot, , ,{ }= P O s( ) ... vt P O m( ) m signal-to-symbol conversion HMM (stationary) HMM (moving procedures) 7. Human control strategy analysis (e.g. driving) 8. Robot control (e.g. autonomous driving) 9
Online analysis and visualization of agent based Arnaud Grignard1
Paris-Sud XI, Universitķ de
is used to study many kind of com- plex systems in different fields such as biology, ecology, or sociology to extract interesting dy- namics in the simulations thanks to the use of analysis tools, data-mining them evolve during simulations. In addition, statistical or data-mining tools are mostly available
Internet-based Self-Services from Analysis and
Miller, John A.
costs (PaaS) #12;ITIL IMS Use Case ŁIncident Management Service (IMS) Ł From ITIL ŁBlueprint >> ŁResolve incidents Ł Disks errors Ł Printers not working ITIL = Information Technology Infrastructure Library #12 into a commercial PaaS platform. #12;Service analysis Ę Use weak semantics to identify ISS main concepts Ę ITIL
Hydrodynamic analysis of mooring lines based on optical tracking experiments
Yang, Woo Seuk
Hydrodynamic Force Coefficients.............................................................................11 18.104.22.168. Deterministic Approach .............................................12 220.127.116.11. Stochastic Approach... Page 2.6. Estimation of Force Transfer Coefficients ...........................................50 2.6.1. Fourier Analysis ......................................................................51 2.6.2. Least Square Minimization...
Accessibility analysis for telecommuting: a GIS-based approach
Chen, Chun
and policy-makers. Research on telecommuting as one solution to reducing travel demand has been active in the past few years. However, most research focuses on analysis of the impact of telecommuting on vehicle-mobility rather than on individual accessibility...
Pretenuring Based on Escape Analysis firstname.lastname@example.com
Jump, Maria
involved pro- #12;ling; our approach instead employs static analysis. 1. INTRODUCTION Garbage collection research area [2, 3, 7, 8]. The generational copying collector is a widely adopted type of garbage]. The memory allocator allocates all objects into the nurs- ery, and the garbage collector collects the nursery
The Phase Inversion-based Coal-CO? Slurry (PHICCOS) feeding system : design, coupled multiscale analysis, and technoeconomic assessment
Botero, Cristina, Ph. D. Massachusetts Institute of Technology
The continuous conveying of a solid feedstock like pulverized coal into a pressurized environment is a challenging task required in multiple industrial processes. Plants based on pressurized, entrained-flow gasifiers (EFG) ...
Feature-based Analysis of Plasma-based Particle Acceleration Data
Ruebel, Oliver
Abstract Plasma-based particle accelerators can produce andconventional particle accelerators, providing a potentialcost of conventional particle accelerators. To facilitate
Terrestrial Remotely Sensed Imagery in Support of Public Health: New Avenues of Research Using Object-Based Image Analysis
Kelly, Maggi
segmentation-based analysis of geospatial data cananalysis of disease ecology and risk: An example using object-based classification techniques. Geospatial
Lockwood, John W.
- rent state of wireless data communication, including the setup of an operating wireless testbed designed to address many of these issues. 1 Introduction The current state of wireless communications can be di- vided into two broad categories based on the designed purpose of particular devices. These two
Control of power characteristics of ion flow in plasma-etching reactor based on beam-plasma discharge
Isaev, N. V.; Klykov, I. L.; Shustin, E. G., E-mail: email@example.com [Russian Academy of Sciences, Kotel'nikov Institute of Radio Engineering and Electronics (Fryazino Branch) (Russian Federation)
It is shown that on the basis of the earlier revealed effect of generating the ion flow in the beam-plasma discharge from the discharge axis, a plasma processing reactor can be created for low-energy etching of semiconductor structures. The possibility of easily controlling the density and energy of ion flow by means of varying the potential of the discharge collector is demonstrated. The charge compensation of the ion flow incident on the nonconducting surface is implemented using the modulation of the potential of the substrate holder as well as the plasma-potential modulation.
Building Energy Performance Analysis of an Academic Building Using IFC BIM-Based Methodology
Aziz, Z.; Arayici, Y.; Shivachev, D.
detailed discussion on various interventions undertaken to calibrate the model. The paper concludes that BIM/IFC based approaches provide a feasible alternative to conduct energy analysis of existing buildings provided various correlations are built...
Analysis of Path Planning Algorithms : a Formal Verification-based Approach Arash Khabbaz Saberi1
Groote, Jan Friso
Analysis of Path Planning Algorithms : a Formal Verification-based Approach Arash Khabbaz Saberi1, The Netherlands firstname.lastname@example.com, email@example.com, firstname.lastname@example.com Abstract
InformationTheoretic Analysis of Privacy Protection for Noisy Identification Based on Soft Fingerprinting
GenĶve, Universitķ de
challenges for the construction of practical codes. Alternatively, the order statistics approaches guarInformationŁTheoretic Analysis of Privacy Protection for Noisy Identification Based on Soft and distinctive content description that allows to overcome fundamental sensitivity restrictions of classical
Open source software maturity model based on linear regression and Bayesian analysis
Zhang, Dongmin
based on Bayesian statistics. More importantly, an updating rule is established through Bayesian analysis to improve the joint distribution, and thus the objectivity of the coefficients in the linear multiple-regression model, according to new incoming...
STAMP-Based Analysis of a Refinery Overflow Accident Nancy Leveson, Margaret Stringfellow, and John Thomas
Leveson, Nancy
1 STAMP-Based Analysis of a Refinery Overflow Accident Nancy Leveson, Margaret Stringfellow, and John Thomas As an example of STAMP, we have taken an accident report produced for a real refinery
Cell Ashing for Trace Element Analysis: A New Approach Based on Ultraviolet/Ozone
Gilbert, Pupa Gelsomina De Stasio
: synchrotron spectromicroscopy; micro- chemical analysis; MEPHISTO; ashing; incineration; trace element. Ashing ashing is based on high-temperature incineration or on the exposure to oxygen plasma (1┬Ł 4). We adopted
On a tensor-based finite element model for the analysis of shell structuresĀ
Arciniega Aleman, Roman Augusto
In the present study, we propose a computational model for the linear and nonlinear analysis of shell structures. We consider a tensor-based finite element formulation which describes the mathematical shell model in a ...
PVP-Vol.246/AMD-Vol. 143,New Methods in Transient Analysis COMPUTATION OF UNSTEADY INCOMPRESSIBLE FLOWS
Mittal, Sanjay
element computation of unsteady in- compressible flows, with emphasis on the space-time formulations, itSST approach the frequency of remeshing is minimized to minimize the projection errors involved in remeshing fluid-structure interaction prob- lems such as vortex-induced oscillations of a cylinder and flow past
An experimental investigation of critical heat flux in subcooled internal flow
Shatto, Donald Patrick
diameters, tube lengths, and mass flow rates. Methods of developing predictive correlations for subcooled critical heat flux based on dimensional analysis, and the sublayer dryout model, are described and applied to the data from these experiments. When...
Monitoring Based Commissioning: Benchmarking Analysis of 24 UC/CSU/IOU Projects
Mills, Evan; Mathew, Paul
Buildings rarely perform as intended, resulting in energy use that is higher than anticipated. Building commissioning has emerged as a strategy for remedying this problem in non-residential buildings. Complementing traditional hardware-based energy savings strategies, commissioning is a 'soft' process of verifying performance and design intent and correcting deficiencies. Through an evaluation of a series of field projects, this report explores the efficacy of an emerging refinement of this practice, known as monitoring-based commissioning (MBCx). MBCx can also be thought of as monitoring-enhanced building operation that incorporates three components: (1) Permanent energy information systems (EIS) and diagnostic tools at the whole-building and sub-system level; (2) Retro-commissioning based on the information from these tools and savings accounting emphasizing measurement as opposed to estimation or assumptions; and (3) On-going commissioning to ensure efficient building operations and measurement-based savings accounting. MBCx is thus a measurement-based paradigm which affords improved risk-management by identifying problems and opportunities that are missed with periodic commissioning. The analysis presented in this report is based on in-depth benchmarking of a portfolio of MBCx energy savings for 24 buildings located throughout the University of California and California State University systems. In the course of the analysis, we developed a quality-control/quality-assurance process for gathering and evaluating raw data from project sites and then selected a number of metrics to use for project benchmarking and evaluation, including appropriate normalizations for weather and climate, accounting for variations in central plant performance, and consideration of differences in building types. We performed a cost-benefit analysis of the resulting dataset, and provided comparisons to projects from a larger commissioning 'Meta-analysis' database. A total of 1120 deficiency-intervention combinations were identified in the course of commissioning the projects described in this report. The most common location of deficiencies was in HVAC equipment (65% of sites), followed by air-handling and distributions systems (59%), cooling plant (29%), heating plants (24%), and terminal units (24%). The most common interventions were adjusting setpoints, modifying sequences of operations, calibration, and various mechanical fixes (each done in about two-thirds of the sites). The normalized rate of occurrence of deficiencies and corresponding interventions ranged from about 0.1/100ksf to 10/100ksf, depending on the issue. From these interventions flowed significant and highly cost-effective energy savings For the MBCx cohort, source energy savings of 22 kBTU/sf-year (10%) were achieved, with a range of 2% to 25%. Median electricity savings were 1.9 kWh/sf-year (9%), with a range of 1% to 17%. Peak electrical demand savings were 0.2 W/sf-year (4%), with a range of 3% to 11%. The aggregate commissioning cost for the 24 projects was $2.9 million. We observed a range of normalized costs from $0.37 to 1.62/sf, with a median value of $1.00/sf for buildings that implemented MBCx projects. Per the program design, monitoring costs as a percentage of total costs are significantly higher in MBCx projects (median value 40%) than typical commissioning projects included in the Meta-analysis (median value of 2% in the commissioning database). Half of the projects were in buildings containing complex and energy-intensive laboratory space, with higher associated costs. Median energy cost savings were $0.25/sf-year, for a median simple payback time of 2.5 years. Significant and cost-effective energy savings were thus obtained. The greatest absolute energy savings and shortest payback times were achieved in laboratory-type facilities. While impacts varied from project to project, on a portfolio basis we find MBCx to be a highly cost-effective means of obtaining significant program-level energy savings across a variety of building types. Energy savings are ex
Global Trade Analysis Project (GTAP) Data Base | Open Energy Information
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are8COaBulkTransmissionSitingProcess.pdfGetec AG Contracting Jump to:Echo,GEF Jump to: navigation,GWTrade Analysis
Analysis of Geothermal Reservoir Stimulation using Geomechanics-Based
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't Your Destiny: The Future of1Albuquerque, NMPerformance |Should184.108.40.2061Stochastic Analysis of
Analysis of Geothermal Reservoir Stimulation using Geomechanics-Based
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't Your Destiny: The Future of1Albuquerque, NMPerformance |Should184.108.40.2061Stochastic Analysis
Design and analysis of an Extended Kalman Filter based navigator for an autonomous underwater vehicleĀ
Just, Bradley Eugene
DESIGN AND ANALYSIS OF AN EXTENDED KALMAN FILTER BASED NAVIGATOR FOR AN AUTONOMOUS UNDERWATER VEHICLE A Thesis by BRADLEY EUGENE JUST Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE May 1994 Major Subject: Mechanical Engineering DESIGN AND ANALYSIS OF AN EXTENDED KALMAN FILTER BASED NAVIGATOR FOR AN AUTONOMOUS UNDERWATER VEHICLE A Thesis by BRADLEY EUGENE JUST Submitted to Texas A...
Design and analysis of an Extended Kalman Filter based navigator for an autonomous underwater vehicle
Just, Bradley Eugene
DESIGN AND ANALYSIS OF AN EXTENDED KALMAN FILTER BASED NAVIGATOR FOR AN AUTONOMOUS UNDERWATER VEHICLE A Thesis by BRADLEY EUGENE JUST Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE May 1994 Major Subject: Mechanical Engineering DESIGN AND ANALYSIS OF AN EXTENDED KALMAN FILTER BASED NAVIGATOR FOR AN AUTONOMOUS UNDERWATER VEHICLE A Thesis by BRADLEY EUGENE JUST Submitted to Texas A...
Transport Analysis of Trace Tritium Experiments on JET using TRANSP Code and Comparison with Theory-Based Transport Models
Transport Analysis of Trace Tritium Experiments on JET using TRANSP Code and Comparison with Theory-Based Transport Models
Stochastic Turing patterns: analysis of compartment-based approaches
Cao, Yang
Turing patterns can be observed in reaction-diffusion systems where chemical species have different diffusion constants. In recent years, several studies investigated the effects of noise on Turing patterns and showed that the parameter regimes, for which stochastic Turing patterns are observed, can be larger than the parameter regimes predicted by deterministic models, which are written in terms of partial differential equations for species concentrations. A common stochastic reaction-diffusion approach is written in terms of compartment-based (lattice-based) models, where the domain of interest is divided into artificial compartments and the number of molecules in each compartment is simulated. In this paper, the dependence of stochastic Turing patterns on the compartment size is investigated. It has previously been shown (for relatively simpler systems) that a modeller should not choose compartment sizes which are too small or too large, and that the optimal compartment size depends on the diffusion consta...
Implementation of electric vehicle system based on solar energy in Singapore assessment of flow batteries for energy storage
Chen, Yaliang
For large-scale energy storage application, flow battery has the advantages of decoupled power and energy management, extended life cycles and relatively low cost of unit energy output ($/kWh). In this thesis, an overview ...
Compressive Sensing Based Machine Learning Strategy For Characterizing The Flow Around A Cylinder With Limited Pressure Measurements
Bright, Ido; Lin, Guang; Kutz, Nathan
Compressive sensing is used to determine the flow characteristics around a cylinder (Reynolds number and pressure/flow field) from a sparse number of pressure measurements on the cylinder. Using a supervised machine learning strategy, library elements encoding the dimensionally reduced dynamics are computed for various Reynolds numbers. Convex L1 optimization is then used with a limited number of pressure measurements on the cylinder to reconstruct, or decode, the full pressure field and the resulting flow field around the cylinder. Aside from the highly turbulent regime (large Reynolds number) where only the Reynolds number can be identified, accurate reconstruction of the pressure field and Reynolds number is achieved. The proposed data-driven strategy thus achieves encoding of the fluid dynamics using the L2 norm, and robust decoding (flow field reconstruction) using the sparsity promoting L1 norm.
A Cumulant-based Analysis of Nonlinear Magnetospheric Dynamics
Jay R. Johnson; Simon Wing
Understanding magnetospheric dynamics and predicting future behavior of the magnetosphere is of great practical interest because it could potentially help to avert catastrophic loss of power and communications. In order to build good predictive models it is necessary to understand the most critical nonlinear dependencies among observed plasma and electromagnetic field variables in the coupled solar wind/magnetosphere system. In this work, we apply a cumulant-based information dynamical measure to characterize the nonlinear dynamics underlying the time evolution of the Dst and Kp geomagnetic indices, given solar wind magnetic field and plasma input. We examine the underlying dynamics of the system, the temporal statistical dependencies, the degree of nonlinearity, and the rate of information loss. We find a significant solar cycle dependence in the underlying dynamics of the system with greater nonlinearity for solar minimum. The cumulant-based approach also has the advantage that it is reliable even in the case of small data sets and therefore it is possible to avoid the assumption of stationarity, which allows for a measure of predictability even when the underlying system dynamics may change character. Evaluations of several leading Kp prediction models indicate that their performances are sub-optimal during active times. We discuss possible improvements of these models based on this nonparametric approach.
SAT-based Termination Analysis for Java Bytecode with AProVE
├übrah├Īm, Erika
SAT-based Termination Analysis for Java Bytecode with AProVE Carsten Fuhs LuFG Informatik 2, RWTH solving engines for the search problems in automated termination analysis. Consequently, the performance of current termination tools heavily relies on the speed of modern SAT solvers on the corresponding SAT
Expert Recommendation based on Social Drivers, Social Network Analysis, and Semantic Data Representation
Fox, Mark S.
Expert Recommendation based on Social Drivers, Social Network Analysis, and Semantic Data-Theoretical Multi-Level (MTML) framework which investigates social drivers for network formation in the communities computational techniques from social network analysis and representational techniques from the semantic web
Energy analysis of substorms based on remote sensing techniques, solar wind measurements, and geomagnetic indices
├?stgaard, Nikolai
Energy analysis of substorms based on remote sensing techniques, solar wind measurements wind Citation: ├?stgaard, N., G. Germany, J. Stadsnes, and R. R. Vondrak, Energy analysis of substorms satellite have been used to examine the energy deposition in the Northern Hemisphere by precipitating
So, Hing-Cheung
SPEECH ENHANCEMENT IN CAR NOISE ENVIRONMENT BASED ON AN ANALYSIS- SYNTHESIS APPROACH USING HARMONIC Kong ABSTRACT This paper presents a speech enhancement method based on an analysis-synthesis framework analysis-synthesis based speech enhancement system, and give details in HNM modeling, parameter estimation
Phylogenetic analysis of paraneopteran orders (Insecta: Neoptera) based on forewing base structure,
Yoshizawa, Kazunori
, with comments on monophyly of Auchenorrhyncha (Hemiptera) K A Z U N O R I Y O S H I Z A W A and T O Y O H E I, Hemiptera and Thysanoptera) were analysed based on the morphology of forewing base structure. Monophyly of Paraneoptera was supported by nine autapomorphies, monophyly of Condylognatha (= Thysanoptera + Hemiptera
Beamforming in MISO Systems: Empirical Results and EVM-based Analysis
1 Beamforming in MISO Systems: Empirical Results and EVM-based Analysis Melissa Duarte, Ashutosh-based study of beamforming Multiple Input Single Output (MISO) systems. We analyze the performance of beamforming MISO systems taking into account implementation complexity and effects of imperfect channel
Reduction of Ground-Based Sensor Sites for Spatio-Temporal Analysis of Aerosols
Vucetic, Slobodan
Reduction of Ground-Based Sensor Sites for Spatio- Temporal Analysis of Aerosols Vladan in this study is estimation of an important property of atmosphere, called Aerosol Optical Depth (AOD). Remote of spatio- temporal aerosol patterns on a global scale. Ground-based AOD estimation is more accurate
On the Formal Analysis of a Spatio-Temporal Role-Based Access Control Model
Ray, Indrakshi
On the Formal Analysis of a Spatio-Temporal Role-Based Access Control Model Manachai Toahchoodee. For crit- ical applications, a model for spatio-temporal-based access control is needed that increases. Consequently, researchers have proposed various spatio-temporal access control models that are useful
Boyer, Edmond
FOUNDATION, ANALYSIS, AND NUMERICAL INVESTIGATION OF A VARIATIONAL NETWORK-BASED MODEL FOR RUBBER, many models based on polymer chain statistics have been proposed to describe rubber elasticity. Recently, Alicandro, Cicalese, and the first author rigorously derived a continuum theory of rubber
Melnik, Roderick
NONLINEAR ANALYSIS OF RUBBER-BASED POLYMERIC MATERIALS WITH THERMAL RELAXATION MODELS R. V. N Queensland, Australia Using mathematical modeling and computer simulation, nonlinear dynamics of rubber in the thermomechanical system. 1. INTRODUCTION The effect of thermal relaxation in rubber-based polymers is one
Save-IDE A Tool for Design, Analysis and Implementation of Component-Based Embedded Systems
Becker, Steffen
Save-IDE Ł A Tool for Design, Analysis and Implementation of Component-Based Embedded Systems S.nystrom, thomas.nolte, paul.pettersson, firstname.lastname@example.com Abstract The paper presents Save-IDE, an Integrated Develop- ment Environment for the development of component-based embedded systems. Save-IDE supports
Shen, Jinglai
DYNAMIC SECURITY ANALYSIS OF ELECTRIC POWER SYSTEMS: PASSIVITY-BASED APPROACH AND POSITIVE in modern power system opera- tion. With the aid of analytic tools for large-scale and hybrid systems, this paper proposes two new safety verification methods for power systems. The first method is based
analysis web-based interface: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
analysis web-based interface First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Web-based Interface in...
Existence of new nonlocal field theory on noncommutative space and spiral flow in renormalization group analysis of matrix models
Kawamoto, Shoichi
In the previous study, we formulate a matrix model renormalization group based on the fuzzy spherical harmonics with which a notion of high/low energy can be attributed to matrix elements, and show that it exhibits locality and various similarity to the usual Wilsonian renormalization group of quantum field theory. In this work, we continue the renormalization group analysis of a matrix model with emphasis on nonlocal interactions where the fields on antipodal points are coupled. They are indeed generated in the renormalization group procedure and are tightly related to the noncommutative nature of the geometry. We aim at formulating renormalization group equations including such nonlocal interactions and finding existence of nontrivial field theory with antipodal interactions on the fuzzy sphere. We find several nontrivial fixed points and calculate the scaling dimensions associated with them. We also consider the noncommutative plane limit and then no consistent fixed point is found. This contrast between t...
A new algorithm for wavelet-based heart rate variability analysis
GarcĒa, Constantino A; Vila, Xosķ; Mßrquez, David G
One of the most promising non-invasive markers of the activity of the autonomic nervous system is Heart Rate Variability (HRV). HRV analysis toolkits often provide spectral analysis techniques using the Fourier transform, which assumes that the heart rate series is stationary. To overcome this issue, the Short Time Fourier Transform is often used (STFT). However, the wavelet transform is thought to be a more suitable tool for analyzing non-stationary signals than the STFT. Given the lack of support for wavelet-based analysis in HRV toolkits, such analysis must be implemented by the researcher. This has made this technique underutilized. This paper presents a new algorithm to perform HRV power spectrum analysis based on the Maximal Overlap Discrete Wavelet Packet Transform (MODWPT). The algorithm calculates the power in any spectral band with a given tolerance for the band's boundaries. The MODWPT decomposition tree is pruned to avoid calculating unnecessary wavelet coefficients, thereby optimizing execution t...
Stability analysis of a phase-field model of gravity-driven unsaturated flow through porous media
Cueto-Felgueroso, Luis
The formation of preferential flow paths during infiltration of water into homogeneous, dry soil is an important phenomenon whose explanation and prediction have remained elusive under the standard theories of multiphase ...
A Robust Four-Fluid Transient Flow Simulator as an Analysis and Decision Making Tool for Dynamic Kill OperationĀ
Haghshenas, Arash
The worst scenario of drilling operation is blowout which is uncontrolled flow of formation fluid into the wellbore. Blowouts result in environmental damage with potential risk of injuries and fatalities. Although not all ...
CFD Analysis of Core Bypass Flow and Crossflow in the Prismatic Very High Temperature Gas-cooled Nuclear ReactorĀ
Wang, Huhu 1985-
Very High Temperature Rector (VHTR) had been designated as one of those promising reactors for the Next Generation (IV) Nuclear Plant (NGNP). For a prismatic core VHTR, one of the most crucial design considerations is the bypass flow and crossflow...
Robinson, J.
PLANTATIONS FIGURE 2 BIOGAS PROCESS TL'BIOGAS _ANAERQBICf o r Other Data Bases >BIOGAS/TI,DE,ID BIO(W)GAS/TI,DE,IDSEARCHES Methane (or Biogas) Production from Agricultural
Macroalgae Analysis A National GIS-based Analysis of Macroalgae Production Potential Summary Report and Project Plan
Roesijadi, Guritno; Coleman, Andre M.; Judd, Chaeli; Van Cleve, Frances B.; Thom, Ronald M.; Buenau, Kate E.; Tagestad, Jerry D.; Wigmosta, Mark S.; Ward, Jeffrey A.
The overall project objective is to conduct a strategic analysis to assess the state of macroalgae as a feedstock for biofuels production. The objective in FY11 is to develop a multi-year systematic national assessment to evaluate the U.S. potential for macroalgae production using a GIS-based assessment tool and biophysical growth model developed as part of these activities. The initial model development for both resource assessment and constraints was completed and applied to the demonstration areas. The model for macroalgal growth was extended to the EEZ off the East and West Coasts of the United States, and a plan to merge the findings for an initial composite assessment was developed. In parallel, an assessment of land-based, port, and offshore infrastructure needs based on published and grey literature was conducted. Major information gaps and challenges encountered during this analysis were identified. Also conducted was an analysis of the type of local, state, and federal requirements that pertain to permitting land-based facilities and nearshore/offshore culture operations
A Monte Carlo based spent fuel analysis safeguards strategy assessment
Fensin, Michael L [Los Alamos National Laboratory; Tobin, Stephen J [Los Alamos National Laboratory; Swinhoe, Martyn T [Los Alamos National Laboratory; Menlove, Howard O [Los Alamos National Laboratory; Sandoval, Nathan P [Los Alamos National Laboratory
Safeguarding nuclear material involves the detection of diversions of significant quantities of nuclear materials, and the deterrence of such diversions by the risk of early detection. There are a variety of motivations for quantifying plutonium in spent fuel assemblies by means of nondestructive assay (NDA) including the following: strengthening the capabilities of the International Atomic Energy Agencies ability to safeguards nuclear facilities, shipper/receiver difference, input accountability at reprocessing facilities and burnup credit at repositories. Many NDA techniques exist for measuring signatures from spent fuel; however, no single NDA technique can, in isolation, quantify elemental plutonium and other actinides of interest in spent fuel. A study has been undertaken to determine the best integrated combination of cost effective techniques for quantifying plutonium mass in spent fuel for nuclear safeguards. A standardized assessment process was developed to compare the effective merits and faults of 12 different detection techniques in order to integrate a few techniques and to down-select among the techniques in preparation for experiments. The process involves generating a basis burnup/enrichment/cooling time dependent spent fuel assembly library, creating diversion scenarios, developing detector models and quantifying the capability of each NDA technique. Because hundreds of input and output files must be managed in the couplings of data transitions for the different facets of the assessment process, a graphical user interface (GUI) was development that automates the process. This GUI allows users to visually create diversion scenarios with varied replacement materials, and generate a MCNPX fixed source detector assessment input file. The end result of the assembly library assessment is to select a set of common source terms and diversion scenarios for quantifying the capability of each of the 12 NDA techniques. We present here the generalized assessment process, the techniques employed to automate the coupled facets of the assessment process, and the standard burnup/enrichment/cooling time dependent spent fuel assembly library. We also clearly define the diversion scenarios that will be analyzed during the standardized assessments. Though this study is currently limited to generic PWR assemblies, it is expected that the results of the assessment will yield an adequate spent fuel analysis strategy knowledge that will help the down-select process for other reactor types.
A framework for graph-based synthesis, analysis, and visualization of HPC cluster job data.
Mayo, Jackson R.; Kegelmeyer, W. Philip, Jr.; Wong, Matthew H.; Pebay, Philippe Pierre; Gentile, Ann C.; Thompson, David C.; Roe, Diana C.; De Sapio, Vincent; Brandt, James M.
The monitoring and system analysis of high performance computing (HPC) clusters is of increasing importance to the HPC community. Analysis of HPC job data can be used to characterize system usage and diagnose and examine failure modes and their effects. This analysis is not straightforward, however, due to the complex relationships that exist between jobs. These relationships are based on a number of factors, including shared compute nodes between jobs, proximity of jobs in time, etc. Graph-based techniques represent an approach that is particularly well suited to this problem, and provide an effective technique for discovering important relationships in job queuing and execution data. The efficacy of these techniques is rooted in the use of a semantic graph as a knowledge representation tool. In a semantic graph job data, represented in a combination of numerical and textual forms, can be flexibly processed into edges, with corresponding weights, expressing relationships between jobs, nodes, users, and other relevant entities. This graph-based representation permits formal manipulation by a number of analysis algorithms. This report presents a methodology and software implementation that leverages semantic graph-based techniques for the system-level monitoring and analysis of HPC clusters based on job queuing and execution data. Ontology development and graph synthesis is discussed with respect to the domain of HPC job data. The framework developed automates the synthesis of graphs from a database of job information. It also provides a front end, enabling visualization of the synthesized graphs. Additionally, an analysis engine is incorporated that provides performance analysis, graph-based clustering, and failure prediction capabilities for HPC systems.
DEVELOPMENT STATUS OF A SiC-FOAM BASED FLOW CHANNEL INSERT FOR A U.S.-ITER DCLL TBM
Ghoniem, Nasr M.
, CA, 91331, U.S.A. The U.S.-ITER DCLL (Dual Coolant Liquid Lead) TBM (Test Blanket Module) uses a Flow structure. I. INTRODUCTION The U.S. ITER Double Coolant Lead Lithium (DCLL) Test Blanket Module (TBM liquid breeder (PbLi) at elevated temperatures of more than 700 o C and at low velocities of ~10 cm
Environmental Analysis of the Coal-based Power Production with Amine-based Carbon Capture
. Based on LCA methodology the study examines the operation of six coal power plants, which differ by the expected efficiency parameters for the year 2020: (1) Coal plant2005: pulverized coal power plant already operating in 2005 (2) Coal plant2010: pulverized coal power plant installed in 2010 (3) Coal plant2020
Voltage Collapse and ODE Approach to Power Flows: Analysis of a Feeder Line with Static Disorder in Consumption/Production
Chertkov, M; Turtisyn, K; Chernyak, V; Lebedev, V
We consider a model of a distribution feeder connecting multiple loads to the sub-station. Voltage is controlled directly at the head of the line (sub-station), however, voltage anywhere further down the line is subject to fluctuations, caused by irregularities of real and reactive distributed power consumption/generation. The lack of a direct control of voltage along the line may result in the voltage instability, also called voltage collapse - phenomenon well known and documented in the power engineering literature. Motivated by emerging photo-voltaic technology, which brings a new source of renewable generation but also contributes significant increase in power flow fluctuations, we reexamine the phenomenon of voltage stability and collapse. In the limit where the number of consumers is large and spatial variations in power flows are smooth functions of position along the feeder, we derive a set of the power flow Ordinary Differential Equations (ODE), verify phenomenon of voltage collapse, and study the ef...
Genetic algorithm evolved agent-based equity trading using Technical Analysis and the Capital Asset Pricing Model
Aickelin, Uwe
Genetic algorithm evolved agent-based equity trading using Technical Analysis and the Capital Asset data using technical analysis, the capital asset pricing model and a hybrid model of the two approaches. Results indicated that the technical analysis based approach performed better than the capital asset
Multi-vehicle Convoy Analysis Based on ANPR data A. Homayounfar*, A. T. S. Ho*, N. Zhu*, G. Head
Doran, Simon J.
Multi-vehicle Convoy Analysis Based on ANPR data A. Homayounfar*, A. T. S. Ho*, N. Zhu*, G. Head mining techniques for convoy analysis of vehicles based on the automatic number plate recognition (ANPR of multi-vehicle convoy activities. 1 Introduction Convoy Analysis of vehicles is a relatively new research
A preliminary analysis of the reactor-based plutonium disposition alternative deployment schedules
Zurn, R.M.
This paper discusses the preliminary analysis of the implementation schedules of the reactor-based plutonium disposition alternatives. These schedule analyses are a part of a larger process to examine the nine decision criteria used to determine the most appropriate method of disposing of U.S. surplus weapons plutonium. The preliminary analysis indicates that the mission durations for the reactor-based alternatives range from eleven years to eighteen years and the initial mission fuel assemblies containing surplus weapons-usable plutonium could be loaded into the reactors between nine and fourteen years after the Record of Decision.
Lee, S.
The primary objective of this work is to quantify the mixing time when two miscible fluids are mixed by one recirculation pump and to evaluate adequacy of 2.5 hours of pump recirculation to be considered well mixed in SRS tanks, JT-71/72. The work scope described here consists of two modeling analyses. They are the steady state flow pattern analysis during pump recirculation operation of the tank liquid and transient species transport calculations based on the initial steady state flow patterns. The modeling calculations for the mixing time are performed by using the 99% homogeneity criterion for the entire domain of the tank contents.
Fusion Engineering and Design 81 (2006) 549553 Numerical analysis of MHD flow and heat transfer in a
Abdou, Mohamed
. Zinkle, M. Youssef, Assessment of liquid breeder first wall and blanket options for the DEMO design, in channels. tural material. Helium cools the fist wall and blanket structure, and the self-cooled breeder, Pb in a poloidal channel of the DCLL blanket with a SiCf/SiC flow channel insert S. Smolentseva,, M. Abdoua, N
Laboratory analysis of fluid flow and solute transport through a variably saturated fracture embedded in porous tuff
Chuang, Y.; Haldeman, W.R.; Rasmussen, T.C.; Evans, D.D. [Arizona Univ., Tucson, AZ (USA). Dept. of Hydrology and Water Resources
Laboratory techniques are developed that allow concurrent measurement of unsaturated matrix hydraulic conductivity and fracture transmissivity of fractured rock blocks. Two Apache Leap tuff blocks with natural fractures were removed from near Superior, Arizona, shaped into rectangular prisms, and instrumented in the laboratory. Porous ceramic plates provided solution to block tops at regulated pressures. Infiltration tests were performed on both test blocks. Steady flow testing of the saturated first block provided estimates of matrix hydraulic conductivity and fracture transmissivity. Fifteen centimeters of suction applied to the second block top showed that fracture flow was minimal and matrix hydraulic conductivity was an order of magnitude less than the first block saturated matrix conductivity. Coated-wire ion-selective electrodes monitored aqueous chlorided breakthrough concentrations. Minute samples of tracer solution were collected with filter paper. The techniques worked well for studying transport behavior at near-saturated flow conditions and also appear to be promising for unsaturated conditions. Breakthrough curves in the fracture and matrix, and a concentration map of chloride concentrations within the fracture, suggest preferential flows paths in the fracture and substantial diffusion into the matrix. Average travel velocity, dispersion coefficient and longitudinal dispersivity in the fracture are obtained. 67 refs., 54 figs., 23 tabs.
Statistical Process Variation Analysis of a Graphene FET based LC-VCO for WLAN Applications
Mohanty, Saraju P.
Statistical Process Variation Analysis of a Graphene FET based LC-VCO for WLAN Applications Md firstname.lastname@example.com, firstname.lastname@example.com, and email@example.com Abstract--Graphene which is a single atom layer-frequency electronics due to low Ion/Ioff ratio. In this paper, design exploration of a graphene FET (GFET) based LC
A Net Energy-based Analysis for a Climate-constrained Sustainable Energy Transition
Sgouridis, Sgouris; Csala, Denes
The transition from a fossil-based energy economy to one based on renewable energy is driven by the double challenge of climate change and resource depletion. Building a renewable energy infrastructure requires an upfront energy investment that subtracts from the net energy available to society. This investment is determined by the need to transition to renewable energy fast enough to stave off the worst consequences of climate change and, at the same time, maintain a sufficient net energy flow to sustain the world's economy and population. We show that a feasible transition pathway requires that the rate of investment in renewable energy should accelerate approximately by an order of magnitude if we are to stay within the range of IPCC recommendations.
Mauve: a Component-based Modeling Framework for Real-time Analysis of Robotic Applications
Mauve: a Component-based Modeling Framework for Real-time Analysis of Robotic Applications Charles paradigm for robotic software devel- opment [2], applied in many applications [3], [4], [5], [6]. Resulting validation of the robotic application, by directly analysing the architecture specification, and limiting
Thermodynamic Cycle Analysis for Wave Rotor Combustor Based Combined Cycle Jessica Collins1
Zhou, Yaoqi
Thermodynamic Cycle Analysis for Wave Rotor Combustor Based Combined Cycle Jessica Collins1 , Brian of Engineering and Technology The conventional combustor that exists in today's market is a constant pressure device; whereas, the wave rotor combustor investigated in the present research is a constant volume
GIS-based Multi-Criteria Analysis of Wind Farm Development Henning Sten Hansen
Hansen, Renķ Rydhof
GIS-based Multi-Criteria Analysis of Wind Farm Development Henning Sten Hansen National on the environment of traditional power- generating methods, especially coal and oil-fired power stations wind power. A project Ł Wind Energy in the Baltic Sea Region - financed by EU / INTERREG III B was initiated in order
Ontology-Based Software Analysis and Reengineering Tool Integration: The OASIS Service-Sharing Methodology
Cordy, James R.
Ontology-Based Software Analysis and Reengineering Tool Integration: The OASIS Service-Sharing Integration System (OASIS) is a novel approach to integration that makes use of specially constructed through service-sharing. This short pa- per provides an outline of the design and function of OASIS. 2
Surface Analysis by Highly Charged Ion Based Secondary Ion Mass Spectrometry
Surface Analysis by Highly Charged Ion Based Secondary Ion Mass Spectrometry T. Schenkel,1 A high vacuum (10^8 torr). In posi- tive polarity, HCI can be decelerated to an impact energy of $1 ke in the interaction of slow (u highly charged ions (e.g., Au69+ ) with solid surfaces increases secondary
Adoption of energy-efficiency measures in SMEs An empirical analysis based on energy audit data
Boyer, Edmond
Adoption of energy-efficiency measures in SMEs Ł An empirical analysis based on energy audit data;Abstract This paper empiricallyinvestigates the factors driving the adoption of energy-efficiency measures on barriers to energy efficiency in SMEs. More specifically, high investment costs, which are captured
Boyer, Edmond
depth of 50 m. Bigger size wind turbines are now designed in order to produce more electrical power thanCOMMENTS ON STRUCTURAL CONDITION ANALYSIS BASED ON STRAIN MEASUREMENTS ON TRIPOD MODEL S. Opoka1, M strain can be valuable indicator of such changes. KEYWORDS : offshore support structure, wind turbine
Multiresolution analysis on zero-dimensional Abelian groups and wavelets bases
Lukomskii, Sergei F [Saratov State University, Saratov (Russian Federation)
For a locally compact zero-dimensional group (G,+{sup .}), we build a multiresolution analysis and put forward an algorithm for constructing orthogonal wavelet bases. A special case is indicated when a wavelet basis is generated from a single function through contractions, translations and exponentiations. Bibliography: 19 titles.
A Quality Based Approach for the Analysis and Design of Business Process Models
Paris-Sud XI, Universit├® de
A Quality Based Approach for the Analysis and Design of Business Process Models Sarah Ayad1 CEDRIC in modeling and improving Business Process (BP) models quality. This problem is of growing interest exploiting domain knowledge. Keywords-component: Business Process Models, Quality metrics, Quality
Experimental Analysis of Task-based Energy Consumption in Cloud Computing Systems
Schneider, Jean-Guy
Experimental Analysis of Task-based Energy Consumption in Cloud Computing Systems Feifei Chen, John is that large cloud data centres consume large amounts of energy and produce significant carbon footprints that minimise energy consumption while guaranteeing Service Level Agreements (SLAs). In order to achieve
Data Distribution Analysis and Optimization for PointerBased Distributed Programs
Lee, Jenq-Kuen
Data Distribution Analysis and Optimization for PointerŁBased Distributed Programs Jenq Kuen Lee Abstract High Performance Fortran (HPF) provides distributed arrays to efficiently support a global name space on distributed memory architectures. The distributed data structures supported by HPF, howŁ ever
European Wind Energy Conference 2007 Milan Measurement based analysis of active and reactive power
European Wind Energy Conference 2007 ┬Ł Milan 1 Measurement based analysis of active and reactive of the electricity is produced by wind turbines and combined heat and power plants (CHPs). Most of them are connected of reactive power between the 60 kV and the 150 kV networks. Further, the TSO is obligated to compensate
Phase Field Dynamic Modelling of Shape Memory Alloys Based on Isogeometric Analysis
Gomez, Hector
Phase Field Dynamic Modelling of Shape Memory Alloys Based on Isogeometric Analysis Rakesh Dhote1 transformations, phase-field model, Ginzburg-Landau theory, nonlinear thermo-elasticity. Abstract. Shape Memory. Introduction Shape Memory Alloys have attracted considerable attention of physicists, engineers and mathemati
Classification of Melanoma Lesions Using Wavelet-based Texture Analysis Rahil Garnavi, Mohammad Aldeen
Bailey, James
Classification of Melanoma Lesions Using Wavelet-based Texture Analysis Rahil Garnavi, Mohammad for classification of melanoma. The method applies tree-structured wavelet transform on different color chan- nels and hidden naive bayes to classify melanoma in a test set of 102 images, which resulted in an accuracy of 88
Computer-aided Diagnosis of Melanoma Using Border and Wavelet-based Texture Analysis
Bailey, James
1 Computer-aided Diagnosis of Melanoma Using Border and Wavelet-based Texture Analysis Rahil presents a novel computer-aided diagno- sis system for melanoma. The novelty lies in the optimised selec of the melanoma lesion. The texture features are derived from using wavelet-decomposition, the border features
An Object-Based Approach to Modelling and Analysis of Failure Properties
Newcastle upon Tyne, University of
based on a protection system from the Nuclear Industry. Keywords: safety analysis, object. Mavko1, S. Riddle2, A. Saeed2 1 Reactor Engineering Division, \\Jozef Stefan" Institute, Ljubljana of the system is likely to increase. The quantitative evidence normally pro- vided for safety certi cation
Cut-off Rate based Outage Probability Analysis of Frequency Hopping Mobile Radio under Jamming
Y²lmaz, ųzg³r
Cut-off Rate based Outage Probability Analysis of Frequency Hopping Mobile Radio under Jamming Conditions G©okhan M. G©uvensen Electrical and Electronics Eng. Dept. Middle East Technical University Ankara, Turkey Email: email@example.com YalcĖin Tanik Electrical and Electronics Eng. Dept. Middle East
Utility based Data Mining for Time Series Analysis -Cost-sensitive Learning for Neural Network Predictors
Weiss, Gary
Utility based Data Mining for Time Series Analysis - Cost-sensitive Learning for Neural firstname.lastname@example.com ABSTRACT In corporate data mining applications, cost-sensitive learning is firmly established Mining General Terms Algorithms, Management, Economics Keywords Data Mining, cost-sensitive learning
Impact of Jitter-based Techniques on Flooding over Wireless Ad hoc Networks: Model and Analysis
Paris-Sud XI, Universitķ de
Impact of Jitter-based Techniques on Flooding over Wireless Ad hoc Networks: Model and Analysis email@example.com Emmanuel Baccelli INRIA, France firstname.lastname@example.com Abstract--Jitter. This paper investigates on the impact of the standardized jitter mechanism on network-wide packet
Query-driven Analysis of Plasma-based Particle Acceleration Data Oliver Rubel
Query-driven Analysis of Plasma-based Particle Acceleration Data Oliver R┬©ubel LBNL Cameron G. R. Geddes LBNL Min Chen LBNL Estelle Cormier-Michel Tech-X Corp. E. W. Bethel LBNL x(x106 ) 2000 4000
A Simple Fuzzy Classifier based on Inconsistency Analysis of Labeled Data
Putten, Peter van der
for designing fuzzy systems for prediction, control, and pattern recognition. Most of these data 2000, fuzzy classifier, model initialisation, direct mail INRODUCTION Data mining and knowledgeA Simple Fuzzy Classifier based on Inconsistency Analysis of Labeled Data J├Īnos Abonyi, Hans Roubos
Fessler, Jeffrey A.
-ray computed tomography. The effects of the quantization error in forward-projection, back computed tomography (CT) have been proposed to improve image quality and reduce dose [1]. These methodsPERTURBATION-BASED ERROR ANALYSIS OF ITERATIVE IMAGE RECONSTRUCTION ALGORITHM FOR X-RAY COMPUTED
Analysis of silicon carbide based semiconductor power devices and their application in power factor correction
Durrani, Yamin Qaisar
electronic switching devices................. 22 2.4.1. SiC Schottky diode................................................................. 22 2.4.2. 4H-SiC PiN diode................................................................... 23 2.4.3. Si...C MOSFET.......................................................................... 23 2.4.4. SiC JFET................................................................................. 23 2.5. Analysis of SiC based Schottky diode...
IEEE TRANSACTIONS ON POWER SYSTEMS 1 Web-based Security Cost Analysis in Electricity
Ca±izares, Claudio A.
IEEE TRANSACTIONS ON POWER SYSTEMS 1 Web-based Security Cost Analysis in Electricity Markets Hong, and describes its implementation using a 3-tier client/server architecture and up-to-date web technologies to certain system parameters. The web implementation allows easy and effective access by all market
JOURNAL OF MATERIALS SCIENCE 38 (2003) 307 322 Crystal plasticity-based finite element analysis
Grujicic, Mica
JOURNAL OF MATERIALS SCIENCE 38 (2003) 307Ł 322 Crystal plasticity-based finite element analysis -TiAl + 2-Ti3Al alloys has been analyzed using a finite element method. A three-dimensional rate interfaces and colony boundaries are implemented in the commercial finite element program Abaqus
Decision Support Modeling and analysis of an auction-based logistics market
Karaesmen, Fikri
Decision Support Modeling and analysis of an auction-based logistics market Semra Agrali a , Baris▀ a logistics spot market where the transportation orders from a number of firms are matched with two types that have lower costs. In order to analyze the effects of implementing a logistics spot market
Current-based 4D shape analysis for the mechanical personalization of heart models
Paris-Sud XI, Universitķ de
Current-based 4D shape analysis for the mechanical personalization of heart models Lo©ic Le Folgoc1. Abstract. Patient-specific models of the heart may lead to better understanding of cardiovascular diseases-mechanical model of the heart, from the kinematics of the endo- and epicardium, is presented in this paper. We use
Trace-Based Analysis and Prediction of Cloud Computing User Behavior Using the Fractal Modeling Technique
Pedram, Massoud
Trace-Based Analysis and Prediction of Cloud Computing User Behavior Using the Fractal Modeling and technology. In this paper, we investigate the characteristics of the cloud computing requests received the alpha- stable distribution. Keywords- cloud computing; alpha-stable distribution; fractional order
Model-based analysis and simulation of regenerative heat wheel Zhuang Wu a
Melnik, Roderick
, which is used in many heat recovery systems. In this paper, a model-based analysis of a rotary Mechanical ventilation with heat recovery systems plays a vital role in securing optimum air quality, thermal heat recovery systems [3]. Such systems have a significant effect on the energy effectiveness
Model-based Failure Modes and Effects Analysis of Neal Snooke 1
Snooke, Neal
embedded software developers who are already familiar with the benefits of FMEA analysis. Several au- thors discuss experiences of performing manual FMEA of software however there has been no attempt at automating of software and the success of model based automated FMEA for hardware. 1 Introduction The notion of Software
An Automated Failure Modes and Effect Analysis Based Visual Matrix Approach to Sensor Selection and
Snooke, Neal
- prehensive automated Failure Modes and Effects Analysis (FMEA) using qualitative model based reasoning techniques. The automated FMEA pro- vides a comprehensive set of faultŁeffect rela- tions by qualitative FMEA results in a fault-effect mapping that can be used to investi- gate the diagnosability
Human-robot interactions: model-based risk analysis and safety case construction
Guiochet, Jķrķmie
Human-robot interactions: model-based risk analysis and safety case construction Quynh Anh DO HOANG potential threats related to physical human-robot interactions and to assess the associated risks that might affect safety and dependability. Because of the complexity of human-robot interactions, rigorous
A finite element analysis of a silicon based double quantum dot structure
S. Rahman; J. Gorman; C. H. W. Barnes; D. A. Williams; H. P. Langtangen
We present the results of a finite-element solution of the Laplace equation for the silicon-based trench-isolated double quantum-dot and the capacitively-coupled single-electron transistor device architecture. This system is a candidate for charge and spin-based quantum computation in the solid state, as demonstrated by recent coherent-charge oscillation experiments. Our key findings demonstrate control of the electric potential and electric field in the vicinity of the double quantum-dot by the electric potential applied to the in-plane gates. This constitutes a useful theoretical analysis of the silicon-based architecture for quantum information processing applications.
Experimental analysis of the vorticity and turbulent flow dynamics of a pitching airfoil at realistic flight (helicopter) conditions
Sahoo, Dipankar
staff members, Karen Knabe, Andrea Loggins, and Colleen Leatherman for their help with official paper work which saved me a lot of time. I extend my gratitude to all employees at the Oran W Nicks Low Speed Wind Tunnel for their valuable assistance... ..................................................... 31 4.1 Oran Nicks Low-Speed Wind Tunnel .................................................. 31 4.1.1 The DSF Inserts ..................................................................... 32 4.1.2 Tunnel Flow...
Reactive Power Compensation Based on FACTs Devices Xunchi Wu (xw2256) Power Systems Analysis Final Project
Lavaei, Javad
..........................................................................................5 2.1 The Thyristor Controlled Reactor (TCR)......................................................................8 III. Power Flow Calculation
Security Analysis of Selected AMI Failure Scenarios Using Agent Based Game Theoretic Simulation
Abercrombie, Robert K [ORNL] [ORNL; Schlicher, Bob G [ORNL] [ORNL; Sheldon, Frederick T [ORNL] [ORNL
Information security analysis can be performed using game theory implemented in dynamic Agent Based Game Theoretic (ABGT) simulations. Such simulations can be verified with the results from game theory analysis and further used to explore larger scale, real world scenarios involving multiple attackers, defenders, and information assets. We concentrated our analysis on the Advanced Metering Infrastructure (AMI) functional domain which the National Electric Sector Cyber security Organization Resource (NESCOR) working group has currently documented 29 failure scenarios. The strategy for the game was developed by analyzing five electric sector representative failure scenarios contained in the AMI functional domain. From these five selected scenarios, we characterize them into three specific threat categories affecting confidentiality, integrity and availability (CIA). The analysis using our ABGT simulation demonstrates how to model the AMI functional domain using a set of rationalized game theoretic rules decomposed from the failure scenarios in terms of how those scenarios might impact the AMI network with respect to CIA.
Capacity Decay Mechanism of Microporous Separator?Based All?Vanadium Redox Flow Batteries and its Recovery
Li, Bin; Luo, Qingtao; Wei, Xiaoliang; Nie, Zimin; Thomsen, Edwin C.; Chen, Baowei; Sprenkle, Vincent L.; Wang, Wei
For all vanadium redox flow batteries (VRBs) with porous separators as membranes, convection effect is found to play a dominant role in the capacity decay of the cells over cycling by investigating the relationship between electrical performances and electrolyte compositions at both positive and negative sides. Although the concentration of total vanadium ions hardly changes at both sides over cycling, the net transfer of solutions from one side to another and thus asymmetrical valance of vanadium ions at both sides lead to the capacity fading and lower energy efficiency, which is confirmed to result from the hydraulic pressure differential at both sides of separators. In this paper, the hydraulic pressures of solutions at both sides can be in-situ monitored, and regulated by varying the gas pressures in electrolyte tanks. It is found that the capacity can be stabilized and the net transfer of solutions can be prevented by slightly tailoring the hydraulic pressure differential at both sides of separators, which, however, doesnÆt work for Nafion membranes, suggesting the negligible convection factor in flow cells using Nafion membranes. Therefore, the possibility of porous separators allows long-term running for VRBs without capacity loss, highlighting a new pathway to develop membranes used in VRBs.
Reservoir characterization based on tracer response and rank analysis of production and injection rates
Refunjol, B.T. [Lagoven, S.A., Pdvsa (Venezuela); Lake, L.W. [Univ. of Texas, Austin, TX (United States)
Quantification of the spatial distribution of properties is important for many reservoir-engineering applications. But, before applying any reservoir-characterization technique, the type of problem to be tackled and the information available should be analyzed. This is important because difficulties arise in reservoirs where production records are the only information for analysis. This paper presents the results of a practical technique to determine preferential flow trends in a reservoir. The technique is a combination of reservoir geology, tracer data, and Spearman rank correlation coefficient analysis. The Spearman analysis, in particular, will prove to be important because it appears to be insightful and uses injection/production data that are prevalent in circumstances where other data are nonexistent. The technique is applied to the North Buck Draw field, Campbell County, Wyoming. This work provides guidelines to assess information about reservoir continuity in interwell regions from widely available measurements of production and injection rates at existing wells. The information gained from the application of this technique can contribute to both the daily reservoir management and the future design, control, and interpretation of subsequent projects in the reservoir, without the need for additional data.
RELAP5 subcooled critical flow model verification
Petelin, S.; Gortnar, O.; Mavko, B. (Institut Jozef Stefan, Ljubljana (Solomon Islands))
We discuss some results of the RELAP5 break modeling during the analysis of International Standard Problem 27 (ISP-27) performed on the BETHSY facility. This study deals with the discontinuity of the RELAP5 critical flow prediction in a strongly subcooled region. Such unrealistic behavior was observed during the pretest simulations of ISP-27. Based on the investigation, a RELAP5 code correction is suggested that ensures a more appropriate simulation of the critical discharge of strongly subcooled liquid.
Model-Based Analysis of the Role of Biological, Hydrological and Geochemical Factors Affecting Uranium Bioremediation
Zhao, Jiao; Scheibe, Timothy D.; Mahadevan, Radhakrishnan
Uranium contamination is a serious concern at several sites motivating the development of novel treatment strategies such as the Geobacter-mediated reductive immobilization of uranium. However, this bioremediation strategy has not yet been optimized for the sustained uranium removal. While several reactive-transport models have been developed to represent Geobacter-mediated bioremediation of uranium, these models often lack the detailed quantitative description of the microbial process (e.g., biomass build-up in both groundwater and sediments, electron transport system, etc.) and the interaction between biogeochemical and hydrological process. In this study, a novel multi-scale model was developed by integrating our recent model on electron capacitance of Geobacter (Zhao et al., 2010) with a comprehensive simulator of coupled fluid flow, hydrologic transport, heat transfer, and biogeochemical reactions. This mechanistic reactive-transport model accurately reproduces the experimental data for the bioremediation of uranium with acetate amendment. We subsequently performed global sensitivity analysis with the reactive-transport model in order to identify the main sources of prediction uncertainty caused by synergistic effects of biological, geochemical, and hydrological processes. The proposed approach successfully captured significant contributing factors across time and space, thereby improving the structure and parameterization of the comprehensive reactive-transport model. The global sensitivity analysis also provides a potentially useful tool to evaluate uranium bioremediation strategy. The simulations suggest that under difficult environments (e.g., highly contaminated with U(VI) at a high migration rate of solutes), the efficiency of uranium removal can be improved by adding Geobacter species to the contaminated site (bioaugmentation) in conjunction with the addition of electron donor (biostimulation). The simulations also highlight the interactive effect of initial cell concentration and flow rate on U(VI) reduction.
Coupled flow and geomechanical analysis for gas production in the Prudhoe Bay Unit L-106 well Unit C gas hydrate deposit in Alaska
Kim, J.
way Coupled Fluid Flow and Geomechanics in Hydrate Deposits.for Coupled Flow and Geomechanics. Soc. Pet. Eng. J. 16(2):for coupled flow and geomechanics: Drained and undrained
Handbook of methods for risk-based analysis of Technical Specification requirements
Samanta, P.K.; Vesely, W.E.
Technical Specifications (TS) requirements for nuclear power plants define the Limiting Conditions for Operation (LCOs) and Surveillance Requirements (SRs) to assure safety during operation. In general, these requirements were based on deterministic analysis and engineering judgments. Experiences with plant operation indicate that some elements of the requirements are unnecessarily restrictive, while others may not be conducive to safety. Improvements in these requirements are facilitated by the availability of plant specific Probabilistic Safety Assessments (PSAs). The use of risk and reliability-based methods to improve TS requirements has gained wide interest because these methods can: quantitatively evaluate the risk impact and justify changes based on objective risk arguments. Provide a defensible basis for these requirements for regulatory applications. The United States Nuclear Regulatory Commission (USNRC) Office of Research is sponsoring research to develop systematic risk-based methods to improve various aspects of TS requirements. The handbook of methods, which is being prepared, summarizes such risk-based methods. The scope of the handbook includes reliability and risk-based methods for evaluating allowed outage times (AOTs), action statements requiring shutdown where shutdown risk may be substantial, surveillance test intervals (STIs), defenses against common-cause failures, managing plant configurations, and scheduling maintenances. For each topic, the handbook summarizes methods of analysis and data needs, outlines the insights to be gained, lists additional references, and presents examples of evaluations.
Wavelet-Based Method for Instability Analysis in Boiling Water Reactors
Espinosa-Paredes, Gilberto; Prieto-Guerrero, Alfonso; Nunez-Carrera, Alejandro; Amador-Garcia, Rodolfo
This paper introduces a wavelet-based method to analyze instability events in a boiling water reactor (BWR) during transient phenomena. The methodology to analyze BWR signals includes the following: (a) the short-time Fourier transform (STFT) analysis, (b) decomposition using the continuous wavelet transform (CWT), and (c) application of multiresolution analysis (MRA) using discrete wavelet transform (DWT). STFT analysis permits the study, in time, of the spectral content of analyzed signals. The CWT provides information about ruptures, discontinuities, and fractal behavior. To detect these important features in the signal, a mother wavelet has to be chosen and applied at several scales to obtain optimum results. MRA allows fast implementation of the DWT. Features like important frequencies, discontinuities, and transients can be detected with analysis at different levels of detail coefficients. The STFT was used to provide a comparison between a classic method and the wavelet-based method. The damping ratio, which is an important stability parameter, was calculated as a function of time. The transient behavior can be detected by analyzing the maximum contained in detail coefficients at different levels in the signal decomposition. This method allows analysis of both stationary signals and highly nonstationary signals in the timescale plane. This methodology has been tested with the benchmark power instability event of Laguna Verde nuclear power plant (NPP) Unit 1, which is a BWR-5 NPP.
TYBO/BENHAM: Model Analysis of Groundwater Flow and Radionuclide Migration from Underground Nuclear Tests in Southwestern Pahute Mesa, Nevada
Andrew Wolfsberg; Lee Glascoe; Guoping Lu; Alyssa; Olson; Peter Lichtner; Maureen McGraw; Terry Cherry; ,; Guy Roemer
Recent field studies have led to the discovery of trace quantities of plutonium originating from the BENHAM underground nuclear test in two groundwater observation wells on Pahute Mesa at the Nevada Test Site. These observation wells are located 1.3 km from the BENHAM underground nuclear test and approximately 300 m from the TYBO underground nuclear test. In addition to plutonium, several other conservative (e.g. tritium) and reactive (e.g. cesium) radionuclides were found in both observation wells. The highest radionuclide concentrations were found in a well sampling a welded tuff aquifer more than 500m above the BENHAM emplacement depth. These measurements have prompted additional investigations to ascertain the mechanisms, processes, and conditions affecting subsurface radionuclide transport in Pahute Mesa groundwater. This report describes an integrated modeling approach used to simulate groundwater flow, radionuclide source release, and radionuclide transport near the BENHAM and TYBO underground nuclear tests on Pahute Mesa. The components of the model include a flow model at a scale large enough to encompass many wells for calibration, a source-term model capable of predicting radionuclide releases to aquifers following complex processes associated with nonisothermal flow and glass dissolution, and site-scale transport models that consider migration of solutes and colloids in fractured volcanic rock. Although multiple modeling components contribute to the methodology presented in this report, they are coupled and yield results consistent with laboratory and field observations. Additionally, sensitivity analyses are conducted to provide insight into the relative importance of uncertainty ranges in the transport parameters.
Preliminary analysis of the possibility of making use of part of the energy flow of zero-point radiation
R. Alvargonzalez; L. S. Soto
The energy flow of zero-point radiation is very great, but difficult to put to use. However, the observations made by Sparnaay in 1958 and by Lamoureux in 1997 reveal the possibility of making use of a very small fraction of that immense amount. This possibility is big enough for such a minute fraction to have significant importance, but such a possibility requires miniaturisation to a degree which may be unattainable. It is worth trying to achieve it, since it would open the way to interstellar travel.
Nonpremixed Combustion in an Accelerating Turning Transonic Flow Undergoing Transition
Liu, Feng
the turbine-blade material limit. Sirignano and Liu [1,2] show by thermodynamic analysis that the thrust and to widen the range of engine operation. Because the flow in a turbine passage is accelerating and power consumption by intentionally burning fuel in the turbine stages. For the ground-based gas turbine, improvement