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Sample records for piping benchmark problems

  1. Piping benchmark problems for the Westinghouse AP600 Standardized Plant

    SciTech Connect

    Bezler, P.; DeGrassi, G.; Braverman, J.; Wang, Y.K.

    1997-01-01

    To satisfy the need for verification of the computer programs and modeling techniques that will be used to perform the final piping analyses for the Westinghouse AP600 Standardized Plant, three benchmark problems were developed. The problems are representative piping systems subjected to representative dynamic loads with solutions developed using the methods being proposed for analysis for the AP600 standard design. It will be required that the combined license licensees demonstrate that their solutions to these problems are in agreement with the benchmark problem set.

  2. Piping benchmark problems for the ABB/CE System 80+ Standardized Plant

    SciTech Connect

    Bezler, P.; DeGrassi, G.; Braverman, J.; Wang, Y.K.

    1994-07-01

    To satisfy the need for verification of the computer programs and modeling techniques that will be used to perform the final piping analyses for the ABB/Combustion Engineering System 80+ Standardized Plant, three benchmark problems were developed. The problems are representative piping systems subjected to representative dynamic loads with solutions developed using the methods being proposed for analysis for the System 80+ standard design. It will be required that the combined license licensees demonstrate that their solution to these problems are in agreement with the benchmark problem set. The first System 80+ piping benchmark is a uniform support motion response spectrum solution for one section of the feedwater piping subjected to safe shutdown seismic loads. The second System 80+ piping benchmark is a time history solution for the feedwater piping subjected to the transient loading induced by a water hammer. The third System 80+ piping benchmark is a time history solution of the pressurizer surge line subjected to the accelerations induced by a main steam line pipe break. The System 80+ reactor is an advanced PWR type.

  3. Piping benchmark problems for the General Electric Advanced Boiling Water Reactor

    SciTech Connect

    Bezler, P.; DeGrassi, G.; Braverman, J.; Wang, Y.K.

    1993-08-01

    To satisfy the need for verification of the computer programs and modeling techniques that will be used to perform the final piping analyses for an advanced boiling water reactor standard design, three benchmark problems were developed. The problems are representative piping systems subjected to representative dynamic loads with solutions developed using the methods being proposed for analysis for the advanced reactor standard design. It will be required that the combined license holders demonstrate that their solutions to these problems are in agreement with the benchmark problem set.

  4. Piping benchmark problems. Volume 1. Dynamic analysis uniform support motion response spectrum method

    SciTech Connect

    Bezler, P.; Hartzman, M.; Reich, M.

    1980-08-01

    A set of benchmark problems and solutions have been developed for verifying the adequacy of computer programs used for dynamic analysis and design of nuclear piping systems by the Response Spectrum Method. The problems range from simple to complex configurations which are assumed to experience linear elastic behavior. The dynamic loading is represented by uniform support motion, assumed to be induced by seismic excitation in three spatial directions. The solutions consist of frequencies, participation factors, nodal displacement components and internal force and moment components. Solutions to associated anchor point motion static problems are not included.

  5. Benchmark problems and solutions

    NASA Technical Reports Server (NTRS)

    Tam, Christopher K. W.

    1995-01-01

    The scientific committee, after careful consideration, adopted six categories of benchmark problems for the workshop. These problems do not cover all the important computational issues relevant to Computational Aeroacoustics (CAA). The deciding factor to limit the number of categories to six was the amount of effort needed to solve these problems. For reference purpose, the benchmark problems are provided here. They are followed by the exact or approximate analytical solutions. At present, an exact solution for the Category 6 problem is not available.

  6. Benchmark analysis for the design of piping systems in advanced reactors

    SciTech Connect

    Bezler, P.; DeGrassi, G.; Braverman, J.; Shounien Hou

    1993-03-01

    To satisfy the need for the verification of the computer programs and modeling techniques that will be used to perform the final piping analyses for an advanced boding water reactor standard design, three piping benchmark problems were developed. The problems are representative piping systems subjected to representative dynamic loads with solutions developed using the methods being proposed for analysis for the advanced reactor standard design. It will be required that the combined license holders demonstrate that their solutions to these problems are in agreement with the benchmark problem set. A summary description of each problem and some sample results are included.

  7. Benchmark analysis for the design of piping systems in advanced reactors

    SciTech Connect

    Bezler, P.; DeGrassi, G.; Braverman, J. ); Shounien Hou )

    1993-01-01

    To satisfy the need for the verification of the computer programs and modeling techniques that will be used to perform the final piping analyses for an advanced boding water reactor standard design, three piping benchmark problems were developed. The problems are representative piping systems subjected to representative dynamic loads with solutions developed using the methods being proposed for analysis for the advanced reactor standard design. It will be required that the combined license holders demonstrate that their solutions to these problems are in agreement with the benchmark problem set. A summary description of each problem and some sample results are included.

  8. MCNP: Photon benchmark problems

    SciTech Connect

    Whalen, D.J.; Hollowell, D.E.; Hendricks, J.S.

    1991-09-01

    The recent widespread, markedly increased use of radiation transport codes has produced greater user and institutional demand for assurance that such codes give correct results. Responding to these pressing requirements for code validation, the general purpose Monte Carlo transport code MCNP has been tested on six different photon problem families. MCNP was used to simulate these six sets numerically. Results for each were compared to the set's analytical or experimental data. MCNP successfully predicted the analytical or experimental results of all six families within the statistical uncertainty inherent in the Monte Carlo method. From this we conclude that MCNP can accurately model a broad spectrum of photon transport problems. 8 refs., 30 figs., 5 tabs.

  9. Computational evaluation of two reactor benchmark problems

    E-print Network

    Cowan, James Anthony

    1998-01-01

    A neutronic evaluation of two reactor benchmark problems was performed. The benchmark problems describe typical PWR uranium and plutonium (mixed oxide) fueled lattices. WIMSd4m, a neutron transport lattice code, was used to evaluate multigroup...

  10. Brief Announcement: The Problem Based Benchmark Suite

    E-print Network

    Brief Announcement: The Problem Based Benchmark Suite Julian Shun Guy E. Blelloch Jeremy T. Fineman@cs.georgetown.edu, phillip.b.gibbons@intel.com ABSTRACT This announcement describes the problem based benchmark suite (PBBS programming language styles, and machine architectures across a broad set of problems. Each benchmark

  11. Benchmark problems in computational aeroacoustics

    NASA Technical Reports Server (NTRS)

    Porter-Locklear, Freda

    1994-01-01

    A recent directive at NASA Langley is aimed at numerically predicting principal noise sources. During my summer stay, I worked with high-order ENO code, developed by Dr. Harold Atkins, for solving the unsteady compressible Navier-Stokes equations, as it applies to computational aeroacoustics (CAA). A CAA workshop, composed of six categories of benchmark problems, has been organized to test various numerical properties of code. My task was to determine the robustness of Atkins' code for these test problems. In one category, we tested the nonlinear wave propagation of the code for the one-dimensional Euler equations, with initial pressure, density, and velocity conditions. Using freestream boundary conditions, our results were plausible. In another category, we solved the linearized two-dimensional Euler equations to test the effectiveness of radiation boundary conditions. Here we utilized MAPLE to compute eigenvalues and eigenvectors of the Jacobian given variable and flux vectors. We experienced a minor problem with inflow and outflow boundary conditions. Next, we solved the quasi one dimensional unsteady flow equations with an incoming acoustic wave of amplitude 10(exp -6). The small amplitude sound wave was incident on a convergent-divergent nozzle. After finding a steady-state solution and then marching forward, our solution indicated that after 30 periods the acoustic wave had dissipated (a period is time required for sound wave to traverse one end of nozzle to other end).

  12. Statistical Controller Design for the Linear Benchmark Problem Authors

    E-print Network

    Statistical Controller Design for the Linear Benchmark Problem for the Benchmark Problem originally presented at the 1990 American Control Conference. Base* *d on some in designing fixed-or* *der robust controllers for the linear benchmark problem [21]. The remaining

  13. Statistical Controller Design for the Linear Benchmark Problem Authors

    E-print Network

    Statistical Controller Design for the Linear Benchmark Problem for the Benchmark Problem originally presented at the 1990 American Control Conference. Base* *d on some algorithm in designing fixed-or* *der robust controllers for the linear benchmark problem [21

  14. Benchmark Problems for Spacecraft Formation Flying Missions

    NASA Technical Reports Server (NTRS)

    Carpenter, J. Russell; Leitner, Jesse A.; Burns, Richard D.; Folta, David C.

    2003-01-01

    To provide high-level focus to distributed space system flight dynamics and control research, several benchmark problems are suggested. These problems are not specific to any current or proposed mission, but instead are intended to capture high-level features that would be generic to many similar missions.

  15. Proben1 ---A Set of Neural Network Benchmark Problems and

    E-print Network

    Prechelt, Lutz

    Proben1 --- A Set of Neural Network Benchmark Problems and Benchmarking Rules Lutz Prechelt plus a set of rules and conventions for carrying out benchmark tests with these or similar problems and how to document neural network benchmarking. The purpose of the problem and rule collection is to give

  16. Benchmark problems for subsurface flow uncertainty quantification

    NASA Astrophysics Data System (ADS)

    Chang, Haibin; Liao, Qinzhuo; Zhang, Dongxiao

    2015-12-01

    In this work, we design a series of benchmark problems for subsurface flow uncertainty quantification. Three basic subsurface flow problems with increasing complexity are selected, which are steady state groundwater flow, groundwater contamination, and multi-phase flow. For the steady state groundwater flow, hydraulic conductivity is assumed to be uncertain, and the uncertain model parameter is assumed to be Gaussian random constant, Gaussian random field, and facies field, respectively. For the other two flow problems, the uncertain model parameter is assumed to be Gaussian random field and facies field, respectively. The statistical property of the uncertain model parameter is specified for each problem. The Monte Carlo (MC) method is used to obtain the benchmark results. The results include the first two statistical moments and the probability density function of the quantities of interest. To verify the MC results, we test the convergence of the results and the reliability of the sampling algorithm. For any existing and newly developed uncertainty quantification methods, which are not (fully) verified, the designed benchmark problems in this work can facilitate the verification process of those methods. For illustration, in this work, we provide a verification of the probabilistic collocation method using the benchmark results.

  17. Robust LQR control for the benchmark problem

    NASA Technical Reports Server (NTRS)

    Douglas, Joel; Athans, Michael

    1991-01-01

    An examination is made of the performance of a linear quadratic regulator which is robust to parametric uncertainty. The controller, which feeds back all states, is based upon Petersen's approach. Simulations show, using the benchmark problem, that remarkable performance robustness can be achieved.

  18. Analysis of ANS LWR physics benchmark problems.

    SciTech Connect

    Taiwo, T. A.

    1998-07-29

    Various Monte Carlo and deterministic solutions to the three PWR Lattice Benchmark Problems recently defined by the ANS Ad Hoc Committee on Reactor Physics Benchmarks are presented. These solutions were obtained using the VIM continuous-energy Monte Carlo code and the DIF3D/WIMS-D4M code package implemented at the Argonne National Laboratory. The code results for the K{sub eff} and relative pin power distribution are compared to measured values. Additionally, code results for the three benchmark-prescribed infinite lattice configurations are also intercompared. The results demonstrate that the codes produce very good estimates of both the K{sub eff} and power distribution for the critical core and the lattice parameters of the infinite lattice configuration.

  19. Benchmark Problems for Space Mission Formation Flying

    NASA Technical Reports Server (NTRS)

    Carpenter, J. Russell; Leitner, Jesse A.; Folta, David C.; Burns, Richard

    2003-01-01

    To provide a high-level focus to distributed space system flight dynamics and control research, several benchmark problems are suggested for space mission formation flying. The problems cover formation flying in low altitude, near-circular Earth orbit, high altitude, highly elliptical Earth orbits, and large amplitude lissajous trajectories about co-linear libration points of the Sun-Earth/Moon system. These problems are not specific to any current or proposed mission, but instead are intended to capture high-level features that would be generic to many similar missions that are of interest to various agencies.

  20. Stochastic robustness synthesis for a benchmark problem

    NASA Technical Reports Server (NTRS)

    Stengel, Robert F.; Marrison, Christopher I.

    1992-01-01

    Stochastic robustness analysis guides the synthesis of robust linear quadratic Gaussian (LQG) regulators for a benchmark control problem. Probabilities of exceeding allowable design limits, including stability, setting time, and control usage, are estimated by Monte Carlo evaluation. Robust, low-gain compensators that fulfill objectives are designed by numerically minimizing quadratic functions of these probabilities. The method is straightforward and makes use of uncomplicated design principles.

  1. 1 INTRODUCTION Benchmark problems have recently been recog-

    E-print Network

    Spencer Jr., Billie F.

    1 INTRODUCTION Benchmark problems have recently been recog- nized as a means to compare in reality. All of the benchmark problems considered so far have focused on the control of buildings (Spencer- opment of a series of benchmark control problems for various classes of civil engineering structures

  2. Statistical Controller Design for the Linear Benchmark Problem V. Koltchinskii

    E-print Network

    Statistical Controller Design for the Linear Benchmark Problem V. Koltchinskii , M. Ariola , C for the Benchmark Problem originally presented at the 1990 American Control Conference. Based on some recent results of our algorithm in designing fixed-order robust controllers for the linear benchmark problem [22

  3. Proben1 | A Set of Neural Network Benchmark Problems and

    E-print Network

    Prechelt, Lutz

    Proben1 | A Set of Neural Network Benchmark Problems and Benchmarking Rules Lutz Prechelt prechelt : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 8 2.2 Benchmark problem used : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 9 2 694092 September 30, 1994 Technical Report 21 94 Abstract Proben1 is a collection of problems for neural

  4. Model Predictive Control For Wind Excited Buildings: A Benchmark Problem

    E-print Network

    Kareem, Ahsan

    1 Model Predictive Control For Wind Excited Buildings: A Benchmark Problem Gang Mei, Student M the second generation benchmark problem for wind-excited building in the Second World Conference on Structural Control. These benchmark problems are ideally suited for comparing the performance of different

  5. Benchmark on Discretization Schemes for Anisotropic Diffusion Problems

    E-print Network

    Herbin, Raphaèle

    Benchmark on Discretization Schemes for Anisotropic Diffusion Problems on General Grids Raphaèle to this benchmark. We address a two-dimensional anisotropic diffusion problem, which is discretized on general@cmi.univ-mrs.fr ABSTRACT. We present here a number of test cases and meshes which were designed to form a benchmark

  6. Standard problems to evaluate piping response computer codes

    SciTech Connect

    Bezler, P.; Subudhi, M.

    1984-01-01

    A program has been underway to evaluate the analysis methods used by industry to qualify nuclear power plant piping. Two objectives of this program are to develop physical benchmarks for validating the accuracy of computer codes used to simulate piping response and to develop improved procedures for calculating the response of multiple supported piping with independent seismic inputs. The status of the program in these two areas is reviewed.

  7. Energy Storage Benchmark Problems Daniel F. Salas1,3

    E-print Network

    Powell, Warren B.

    Energy Storage Benchmark Problems Daniel F. Salas1,3 , Warren B. Powell2,3 1 Department of Chemical and then design a set of benchmark problems which can be solved exactly. The exact solution to each one A General Storage Problem 1 2.1 The State of The System

  8. Development of Experimental Benchmark Problems for International Collaboration in Structural Response Control

    E-print Network

    Lynch, Jerome P.

    Development of Experimental Benchmark Problems for International Collaboration in Structural. An extensive analysis of benchmark structural control problems formed the basis for a special issue benchmark problems have also been developed for bridge structures subjected to seismic excitation through

  9. Statistical Controller Design for the Linear Benchmark Problem V. Koltchinskii*, M. Ariolay, C.T. Abdallahz

    E-print Network

    Statistical Controller Design for the Linear Benchmark Problem V some fixed-order controllers are designed via statistical * *methods for the Benchmark Problem benchmark problem [21]. The remaining of this paper is divided as follows: Section 2 contains the pr

  10. Statistical Controller Design for the Linear Benchmark Problem V. Koltchinskii*, M. Ariolay, C.T. Abdallahz

    E-print Network

    Statistical Controller Design for the Linear Benchmark Problem V some fixed-order controllers are designed via statistical * *methods for the Benchmark Problem benchmark problem [22]. The remaining of this paper is divided as follows: Section 2 contains the pr

  11. Benchmark problems and results for verifying resonance calculation methodologies

    SciTech Connect

    Wu, H.; Yang, W.; Qin, Y.; He, L.; Cao, L.; Zheng, Y.; Liu, Q.

    2012-07-01

    Resonance calculation is one of the most important procedures for the multi-group neutron transport calculation. With the development of nuclear reactor concepts, many new types of fuel assembly are raised. Compared to the traditional designs, most of the new fuel assemblies have different fuel types either with complex isotopes or with complicated geometry. This makes the traditional resonance calculation method invalid. Recently, many advanced resonance calculation methods are proposed. However, there are few benchmark problems for evaluating those methods with a comprehensive comparison. In this paper, we design 5 groups of benchmark problems including 21 typical cases of different geometries and fuel contents. The reference results of the benchmark problems are generated based on the sub-group method, ultra-fine group method, function expanding method and Monte Carlo method. It is shown that those benchmark problems and their results could be helpful to evaluate the validity of the newly developed resonance calculation method in the future work. (authors)

  12. Simplified two and three dimensional HTTR benchmark problems

    SciTech Connect

    Zhan Zhang; Dingkang Zhang; Justin M. Pounders; Abderrafi M. Ougouag

    2011-05-01

    To assess the accuracy of diffusion or transport methods for reactor calculations, it is desirable to create heterogeneous benchmark problems that are typical of whole core configurations. In this paper we have created two and three dimensional numerical benchmark problems typical of high temperature gas cooled prismatic cores. Additionally, a single cell and single block benchmark problems are also included. These problems were derived from the HTTR start-up experiment. Since the primary utility of the benchmark problems is in code-to-code verification, minor details regarding geometry and material specification of the original experiment have been simplified while retaining the heterogeneity and the major physics properties of the core from a neutronics viewpoint. A six-group material (macroscopic) cross section library has been generated for the benchmark problems using the lattice depletion code HELIOS. Using this library, Monte Carlo solutions are presented for three configurations (all-rods-in, partially-controlled and all-rods-out) for both the 2D and 3D problems. These solutions include the core eigenvalues, the block (assembly) averaged fission densities, local peaking factors, the absorption densities in the burnable poison and control rods, and pin fission density distribution for selected blocks. Also included are the solutions for the single cell and single block problems.

  13. Numerical Solutions to the Third CAA Workshop Benchmark Problems

    NASA Technical Reports Server (NTRS)

    Loh, Roy H.; Lin, Wen H.

    2000-01-01

    This paper presents numerical solutions to the problems of propagation of sound waves through a transonic nozzle, shock-sound interactions, and automobile noise involving feedback of the third NASA Computational Aeroacoustics (CAA) Workshop on benchmark problems. The numerical algorithm is based on a dual time scheme for temporal discretization and a third-order finite volume scheme for spatial discretization. The aims of this study are to apply a dual time stepping scheme to treat aeroacoustic problems of sound propagation and to validate our CAA solver with the benchmark problems for developing a numerical tool for noise analysis and control.

  14. BNL piping research

    SciTech Connect

    Bezler, P.; Subudhi, M.; Wang, Y.K.; Shteyngart, S.

    1985-01-01

    Brookhaven National Laboratory (BNL) has assisted in the development of methods to evaluate the analysis methods used by industry to qualify nuclear power piping. Through FY 1985 these efforts were conducted under the Mechanical Piping Benchmarks project while current and future efforts will be performed under the Combination Procedures for piping project. Under these projects BNL has developed analytical benchmark problems for piping systems evaluated using uniform or independent support motion response spectrum methods, investigated the adequacy and limitations of linear piping analysis methods by comparison to test results and evaluated and developed criteria for new and alternate methods of analysis. A summary description of the status of these efforts is provided.

  15. A proposed benchmark problem for cargo nuclear threat monitoring

    NASA Astrophysics Data System (ADS)

    Wesley Holmes, Thomas; Calderon, Adan; Peeples, Cody R.; Gardner, Robin P.

    2011-10-01

    There is currently a great deal of technical and political effort focused on reducing the risk of potential attacks on the United States involving radiological dispersal devices or nuclear weapons. This paper proposes a benchmark problem for gamma-ray and X-ray cargo monitoring with results calculated using MCNP5, v1.51. The primary goal is to provide a benchmark problem that will allow researchers in this area to evaluate Monte Carlo models for both speed and accuracy in both forward and inverse calculational codes and approaches for nuclear security applications. A previous benchmark problem was developed by one of the authors (RPG) for two similar oil well logging problems (Gardner and Verghese, 1991, [1]). One of those benchmarks has recently been used by at least two researchers in the nuclear threat area to evaluate the speed and accuracy of Monte Carlo codes combined with variance reduction techniques. This apparent need has prompted us to design this benchmark problem specifically for the nuclear threat researcher. This benchmark consists of conceptual design and preliminary calculational results using gamma-ray interactions on a system containing three thicknesses of three different shielding materials. A point source is placed inside the three materials lead, aluminum, and plywood. The first two materials are in right circular cylindrical form while the third is a cube. The entire system rests on a sufficiently thick lead base so as to reduce undesired scattering events. The configuration was arranged in such a manner that as gamma-ray moves from the source outward it first passes through the lead circular cylinder, then the aluminum circular cylinder, and finally the wooden cube before reaching the detector. A 2 in.4 in.16 in. box style NaI (Tl) detector was placed 1 m from the point source located in the center with the 4 in.16 in. side facing the system. The two sources used in the benchmark are 137Cs and 235U.

  16. Second Computational Aeroacoustics (CAA) Workshop on Benchmark Problems

    NASA Technical Reports Server (NTRS)

    Tam, C. K. W. (Editor); Hardin, J. C. (Editor)

    1997-01-01

    The proceedings of the Second Computational Aeroacoustics (CAA) Workshop on Benchmark Problems held at Florida State University are the subject of this report. For this workshop, problems arising in typical industrial applications of CAA were chosen. Comparisons between numerical solutions and exact solutions are presented where possible.

  17. Results of two new methods for aeroacoustics benchmark problems

    NASA Technical Reports Server (NTRS)

    Huynh, H. T.

    1995-01-01

    Two new methods for the numerical solution of conservation laws (the Euler equations in particular) are presented: a uniformly second-order accurate upwind scheme and a third-order accurate centered scheme. Results of these schemes are shown for problems 1, 2, and 5 of this workshop's benchmark problems.

  18. Benchmark problem for model abstraction techniques

    NASA Astrophysics Data System (ADS)

    Plotz, Gary A.; Karle, Thomas A.

    1999-06-01

    Modeling of real systems relies on the arduous task of describing the physical phenomena in terms of mathematical models, which often require excessive amounts of computation time in their execution. In the last few years there has been a growing acceptance of model abstraction whose emphasis rests on the development of more manageable models. Abstraction refers to the intelligent capture of the essence of the behavior of a model, without all the details. In the past, metamodels have been generated from complex models, such as the Tactical Electronic Reconnaissance Simulation Model (TERSM). The scope of this paper is to explore the ability of previously developed TERSM metamodels to accurately simulate the benchmark model using both limited subsets of the original data, and data subsets whose values are interpolated or extrapolated from the original data set used to generate and fit the model. This paper establishes a baseline from which additional metamodels can be compared and analyzed.

  19. Benchmark problems for wavelength dependent continuum radiative transfer

    E-print Network

    Z. Ivezic; M. Groenewegen; A. Menshchikov; R. Szczerba

    1997-05-20

    When verifying a sophisticated numerical code, it is a usual practice to compare the results with reliable solutions obtained by other means. This work provides such solutions for the wavelength dependent dust radiative transfer problem. We define a set of benchmark problems in spherical geometry and solve them by three radiative transfer codes which implement different numerical schemes. Results for the dust temperature and emerging spectra agree to better than 0.1%, and can be used as benchmark solutions for the verification of the dust radiative transfer codes.

  20. Third Computational Aeroacoustics (CAA) Workshop on Benchmark Problems

    NASA Technical Reports Server (NTRS)

    Dahl, Milo D. (Editor)

    2000-01-01

    The proceedings of the Third Computational Aeroacoustics (CAA) Workshop on Benchmark Problems cosponsored by the Ohio Aerospace Institute and the NASA Glenn Research Center are the subject of this report. Fan noise was the chosen theme for this workshop with representative problems encompassing four of the six benchmark problem categories. The other two categories were related to jet noise and cavity noise. For the first time in this series of workshops, the computational results for the cavity noise problem were compared to experimental data. All the other problems had exact solutions, which are included in this report. The Workshop included a panel discussion by representatives of industry. The participants gave their views on the status of applying computational aeroacoustics to solve practical industry related problems and what issues need to be addressed to make CAA a robust design tool.

  1. Benchmarking transport solvers for fracture flow problems

    NASA Astrophysics Data System (ADS)

    Olkiewicz, Piotr; Dabrowski, Marcin

    2015-04-01

    Fracture flow may dominate in rocks with low porosity and it can accompany both industrial and natural processes. Typical examples of such processes are natural flows in crystalline rocks and industrial flows in geothermal systems or hydraulic fracturing. Fracture flow provides an important mechanism for transporting mass and energy. For example, geothermal energy is primarily transported by the flow of the heated water or steam rather than by the thermal diffusion. The geometry of the fracture network and the distribution of the mean apertures of individual fractures are the key parameters with regard to the fracture network transmissivity. Transport in fractures can occur through the combination of advection and diffusion processes like in the case of dissolved chemical components. The local distribution of the fracture aperture may play an important role for both flow and transport processes. In this work, we benchmark various numerical solvers for flow and transport processes in a single fracture in 2D and 3D. Fracture aperture distributions are generated by a number of synthetic methods. We examine a single-phase flow of an incompressible viscous Newtonian fluid in the low Reynolds number limit. Periodic boundary conditions are used and a pressure difference is imposed in the background. The velocity field is primarly found using the Stokes equations. We systematically compare the obtained velocity field to the results obtained by solving the Reynolds equation. This allows us to examine the impact of the aperture distribution on the permeability of the medium and the local velocity distribution for two different mathematical descriptions of the fracture flow. Furthermore, we analyse the impact of aperture distribution on the front characteristics such as the standard deviation and the fractal dimension for systems in 2D and 3D.

  2. Robustness of solutions to a benchmark control problem

    NASA Technical Reports Server (NTRS)

    Stengel, Robert F.; Marrison, Christopher I.

    1991-01-01

    The stochastic robustness of solutions to a benchmark control design problem has been analyzed. The analysis quantifies the controllers' stability and performance robustness with structured uncertainties in up to six system parameters. The analysis provides insights about system response that are not readily derived from other robustness criteria, providing a common ground for judging controllers produced by alternative methods.

  3. Quadratic stabilization and tracking - Applications to the benchmark problem

    NASA Technical Reports Server (NTRS)

    Schmitendorf, W. E.; Dolphus, R. M.; Benson, R. W.

    1992-01-01

    Recent results regarding quadratic stabilization and disturbance attenuation are applied to the benchmark problem. The authors investigate the minimum achievable levels of disturbance attenuation for different disturbance inputs and controlled outputs. They then design a feedforward tracking controller which tracks step inputs while maintaining the disturbance attenuation properties of the regulator.

  4. The DATA-CHASER and Citizen Explorer Benchmark Problem Sets

    E-print Network

    Schaffer, Steven

    (s), and one or more simulations. The first mission is the DATA-CHASER shuttle payload that flew onboard space of Technology {firstname.lastname}@jpl.nasa.gov 2 Previously at Space Grant Consortium, University of Colorado, currently at (1) Abstract. This paper introduces two benchmark problem sets based on actual space mission

  5. Validation of NESTLE against static reactor benchmark problems

    SciTech Connect

    Mosteller, R.D.

    1996-02-01

    The NESTLE advanced modal code was developed at North Carolina State University with support from Los Alamos National Laboratory and Idaho National Engineering Laboratory. It recently has been benchmarked successfully against measured data from pressurized water reactors (PWRs). However, NESTLE`s geometric capabilities are very flexible, and it can be applied to a variety of other types of reactors. This study presents comparisons of NESTLE results with those from other codes for static benchmark problems for PWRs, boiling water reactors (BWRs), high-temperature gas-cooled reactors (HTGRs) and CANDU heavy- water reactors (HWRs).

  6. Benchmark problems in which equality plays the major role

    SciTech Connect

    Lusk, E.; Wos, L.

    1992-05-01

    We have recently heard rumors that researchers are again studying paramodulation [Wos87] in the context of strategy for its control. In part to facilitate such research, and in part to provide test problems for evaluating other approaches to equality-oriented reasoning, we offer in this article a set of benchmark problems in which equality plays the dominant role. The test problems are taken from group theory, Robbins algebra, combinatory logic, and other areas. For each problem, we include appropriate clauses and comment as to its status with regard to provability by an unaided automated reasoning program.

  7. Benchmark problems in which equality plays the major role

    SciTech Connect

    Lusk, E.; Wos, L.

    1992-01-01

    We have recently heard rumors that researchers are again studying paramodulation (Wos87) in the context of strategy for its control. In part to facilitate such research, and in part to provide test problems for evaluating other approaches to equality-oriented reasoning, we offer in this article a set of benchmark problems in which equality plays the dominant role. The test problems are taken from group theory, Robbins algebra, combinatory logic, and other areas. For each problem, we include appropriate clauses and comment as to its status with regard to provability by an unaided automated reasoning program.

  8. American Institute of Aeronautics and Astronautics Simulation of CAA Benchmark Problems Using High-Order

    E-print Network

    Wang, Zhi Jian "ZJ"

    1 American Institute of Aeronautics and Astronautics Simulation of CAA Benchmark Problems Using difference (SD) method is used for the numerical simulation of several benchmark problems in computational problem" in Category 4 of the Fourth Computational Aeroacoustics (CAA) Workshop on Benchmark Problems1

  9. An L2 Disturbance Attenuation Solution to the Nonlinear Benchmark Problem

    E-print Network

    Tsiotras, Panagiotis

    An L2 Disturbance Attenuation Solution to the Nonlinear Benchmark Problem Panagiotis Tsiotras) and nonlinear systems to obtain solutions to the Nonlinear Benchmark Problem (NLBP) proposed in the paper obtained from the linearized problem.) Keywords: Nonlinear Benchmark Problem, Hamilton-Jacobi Equation

  10. MODEL PREDICTION RESULTS FOR 2008 ULTRASONIC BENCHMARK PROBLEMS

    SciTech Connect

    Kim, Hak-Joon; Song, Sung-Jin

    2009-03-03

    The World Federation of NDE Centers (WFNDEC) has addressed two types of problems for the 2008 ultrasonic benchmark problems: effects of surface curvatures on the ultrasonic responses of flat-bottomed holes, and prediction of side-drilled hole responses at various depths in a steel block. To solve this year ultrasonic benchmark problems, multi-Gaussian beam models was adopted for calculation of insonifying fields on the flat-bottomed holes and the side-drilled holes. And, the Kirchhoff approximation and the separation of variables method were applied for calculation of far-field scattering amplitudes of flat-bottomed holes and side-drilled holes, respectively. In this paper, we present comparison of the model predictions to the experiments for side-drilled holes and discuss the effect of interface curvatures on ultrasonic responses by comparison of the peak-to-peak amplitudes of the flat-bottomed hole responses with different interface curvatures.

  11. Benchmark-Problem Instances for Static Scheduling of Task Graphs with Communication Delays on

    E-print Network

    Davidoviæ, Tatjana

    Benchmark-Problem Instances for Static Scheduling of Task Graphs with Communication Delays are the method of choice in all but the simplest cases. The utilization of ac- knowledged sets of benchmark-problem delays, benchmark- problem instances R´esum´e L'allocation et l'ordonnancement de t^aches sur les

  12. An L2 Disturbance Attenuation Approach to the Nonlinear Benchmark Problem

    E-print Network

    Tsiotras, Panagiotis

    An L2 Disturbance Attenuation Approach to the Nonlinear Benchmark Problem Panagiotis Tsiotras Dept) and nonlinear systems to obtain solutions to the Nonlinear Benchmark Problem (NLBP) proposed in the companion methodologies. The Nonlinear Benchmark Problem (NLBP) proposed by Bupp et. al. 2] is an initial attempt

  13. Fourth Computational Aeroacoustics (CAA) Workshop on Benchmark Problems

    NASA Technical Reports Server (NTRS)

    Dahl, Milo D. (Editor)

    2004-01-01

    This publication contains the proceedings of the Fourth Computational Aeroacoustics (CAA) Workshop on Benchmark Problems. In this workshop, as in previous workshops, the problems were devised to gauge the technological advancement of computational techniques to calculate all aspects of sound generation and propagation in air directly from the fundamental governing equations. A variety of benchmark problems have been previously solved ranging from simple geometries with idealized acoustic conditions to test the accuracy and effectiveness of computational algorithms and numerical boundary conditions; to sound radiation from a duct; to gust interaction with a cascade of airfoils; to the sound generated by a separating, turbulent viscous flow. By solving these and similar problems, workshop participants have shown the technical progress from the basic challenges to accurate CAA calculations to the solution of CAA problems of increasing complexity and difficulty. The fourth CAA workshop emphasized the application of CAA methods to the solution of realistic problems. The workshop was held at the Ohio Aerospace Institute in Cleveland, Ohio, on October 20 to 22, 2003. At that time, workshop participants presented their solutions to problems in one or more of five categories. Their solutions are presented in this proceedings along with the comparisons of their solutions to the benchmark solutions or experimental data. The five categories for the benchmark problems were as follows: Category 1:Basic Methods. The numerical computation of sound is affected by, among other issues, the choice of grid used and by the boundary conditions. Category 2:Complex Geometry. The ability to compute the sound in the presence of complex geometric surfaces is important in practical applications of CAA. Category 3:Sound Generation by Interacting With a Gust. The practical application of CAA for computing noise generated by turbomachinery involves the modeling of the noise source mechanism as a vortical gust interacting with an airfoil. Category 4:Sound Transmission and Radiation. Category 5:Sound Generation in Viscous Problems. Sound is generated under certain conditions by a viscous flow as the flow passes an object or a cavity.

  14. National Energy Software Center: benchmark problem book. Revision

    SciTech Connect

    1985-12-01

    Computational benchmarks are given for the following problems: (1) Finite-difference, diffusion theory calculation of a highly nonseparable reactor, (2) Iterative solutions for multigroup two-dimensional neutron diffusion HTGR problem, (3) Reference solution to the two-group diffusion equation, (4) One-dimensional neutron transport transient solutions, (5) To provide a test of the capabilities of multi-group multidimensional kinetics codes in a heavy water reactor, (6) Test of capabilities of multigroup neutron diffusion in LMFBR, and (7) Two-dimensional PWR models.

  15. RADIOGRAPHIC BENCHMARK PROBLEM 2009 - SCATTER CALCULATIONS IN MODELLING

    SciTech Connect

    Jaenisch, G.-R.; Bellon, C.; Schumm, A.; Tabary, J.; Duvauchelle, Ph.

    2010-02-22

    Code Validation is a permanent concern in computer simulation, and has been addressed repeatedly in eddy current and ultrasonic modelling. A good benchmark problem is sufficiently simple to be taken into account by various codes without strong requirements on geometry representation capabilities, focuses on few or even a single aspect of the problem at hand to facilitate interpretation and to avoid that compound errors compensate themselves, yields a quantitative result and is experimentally accessible. In this paper we attempt to address code validation for one aspect of radio-graphic modelling, the scattered radiation prediction. An update of the results of the 2008 benchmark is presented. Additionally we discuss the extension of this benchmark on the lower energy part for 60 and 80 keV as well as for higher energies up to 10 MeV to study the contribution of pair production. Of special interest will be the primary radiation (attenuation law as reference), the total scattered radiation, the relative contribution of scattered radiation separated by order of scatter events (1st, 2nd, ..., 20th), and the spectrum of scattered radiation. We present the results of three Monte Carlo codes (MC-Ray, Sindbad and Moderato) as well as an analytical first order scattering code (VXI) and compare to MCNP as reference.

  16. Workshops and problems for benchmarking eddy current codes

    SciTech Connect

    Turner, L.R.; Davey, K.; Ida, N.; Rodger, D.; Kameari, A.; Bossavit, A.; Emson, C.R.I.

    1988-08-01

    A series of six workshops was held in 1986 and 1987 to compare eddy current codes, using six benchmark problems. The problems included transient and steady-state ac magnetic fields, close and far boundary conditions, magnetic and non-magnetic materials. All the problems were based either on experiments or on geometries that can be solved analytically. The workshops and solutions to the problems are described. Results show that many different methods and formulations give satisfactory solutions, and that in many cases reduced dimensionality or coarse discretization can give acceptable results while reducing the computer time required. A second two-year series of TEAM (Testing Electromagnetic Analysis Methods) workshops, using six more problems, is underway. 12 refs., 15 figs., 4 tabs.

  17. Benchmark Problems Used to Assess Computational Aeroacoustics Codes

    NASA Technical Reports Server (NTRS)

    Dahl, Milo D.; Envia, Edmane

    2005-01-01

    The field of computational aeroacoustics (CAA) encompasses numerical techniques for calculating all aspects of sound generation and propagation in air directly from fundamental governing equations. Aeroacoustic problems typically involve flow-generated noise, with and without the presence of a solid surface, and the propagation of the sound to a receiver far away from the noise source. It is a challenge to obtain accurate numerical solutions to these problems. The NASA Glenn Research Center has been at the forefront in developing and promoting the development of CAA techniques and methodologies for computing the noise generated by aircraft propulsion systems. To assess the technological advancement of CAA, Glenn, in cooperation with the Ohio Aerospace Institute and the AeroAcoustics Research Consortium, organized and hosted the Fourth CAA Workshop on Benchmark Problems. Participants from industry and academia from both the United States and abroad joined to present and discuss solutions to benchmark problems. These demonstrated technical progress ranging from the basic challenges to accurate CAA calculations to the solution of CAA problems of increasing complexity and difficulty. The results are documented in the proceedings of the workshop. Problems were solved in five categories. In three of the five categories, exact solutions were available for comparison with CAA results. A fourth category of problems representing sound generation from either a single airfoil or a blade row interacting with a gust (i.e., problems relevant to fan noise) had approximate analytical or completely numerical solutions. The fifth category of problems involved sound generation in a viscous flow. In this case, the CAA results were compared with experimental data.

  18. The rotating movement of three immiscible fluids - A benchmark problem

    USGS Publications Warehouse

    Bakker, M.; Oude, Essink G.H.P.; Langevin, C.D.

    2004-01-01

    A benchmark problem involving the rotating movement of three immiscible fluids is proposed for verifying the density-dependent flow component of groundwater flow codes. The problem consists of a two-dimensional strip in the vertical plane filled with three fluids of different densities separated by interfaces. Initially, the interfaces between the fluids make a 45??angle with the horizontal. Over time, the fluids rotate to the stable position whereby the interfaces are horizontal; all flow is caused by density differences. Two cases of the problem are presented, one resulting in a symmetric flow field and one resulting in an asymmetric flow field. An exact analytical solution for the initial flow field is presented by application of the vortex theory and complex variables. Numerical results are obtained using three variable-density groundwater flow codes (SWI, MOCDENS3D, and SEAWAT). Initial horizontal velocities of the interfaces, as simulated by the three codes, compare well with the exact solution. The three codes are used to simulate the positions of the interfaces at two times; the three codes produce nearly identical results. The agreement between the results is evidence that the specific rotational behavior predicted by the models is correct. It also shows that the proposed problem may be used to benchmark variable-density codes. It is concluded that the three models can be used to model accurately the movement of interfaces between immiscible fluids, and have little or no numerical dispersion. ?? 2003 Elsevier B.V. All rights reserved.

  19. A PROPOSED BENCHMARK PROBLEM FOR SCATTER CALCULATIONS IN RADIOGRAPHIC MODELLING

    SciTech Connect

    Jaenisch, G.-R.; Bellon, C.; Schumm, A.; Tabary, J.; Duvauchelle, Ph.

    2009-03-03

    Code Validation is a permanent concern in computer modelling, and has been addressed repeatedly in eddy current and ultrasonic modeling. A good benchmark problem is sufficiently simple to be taken into account by various codes without strong requirements on geometry representation capabilities, focuses on few or even a single aspect of the problem at hand to facilitate interpretation and to avoid that compound errors compensate themselves, yields a quantitative result and is experimentally accessible. In this paper we attempt to address code validation for one aspect of radiographic modeling, the scattered radiation prediction. Many NDT applications can not neglect scattered radiation, and the scatter calculation thus is important to faithfully simulate the inspection situation. Our benchmark problem covers the wall thickness range of 10 to 50 mm for single wall inspections, with energies ranging from 100 to 500 keV in the first stage, and up to 1 MeV with wall thicknesses up to 70 mm in the extended stage. A simple plate geometry is sufficient for this purpose, and the scatter data is compared on a photon level, without a film model, which allows for comparisons with reference codes like MCNP. We compare results of three Monte Carlo codes (McRay, Sindbad and Moderato) as well as an analytical first order scattering code (VXI), and confront them to results obtained with MCNP. The comparison with an analytical scatter model provides insights into the application domain where this kind of approach can successfully replace Monte-Carlo calculations.

  20. Numerical Boundary Conditions for Computational Aeroacoustics Benchmark Problems

    NASA Technical Reports Server (NTRS)

    Tam, Chritsopher K. W.; Kurbatskii, Konstantin A.; Fang, Jun

    1997-01-01

    Category 1, Problems 1 and 2, Category 2, Problem 2, and Category 3, Problem 2 are solved computationally using the Dispersion-Relation-Preserving (DRP) scheme. All these problems are governed by the linearized Euler equations. The resolution requirements of the DRP scheme for maintaining low numerical dispersion and dissipation as well as accurate wave speeds in solving the linearized Euler equations are now well understood. As long as 8 or more mesh points per wavelength is employed in the numerical computation, high quality results are assured. For the first three categories of benchmark problems, therefore, the real challenge is to develop high quality numerical boundary conditions. For Category 1, Problems 1 and 2, it is the curved wall boundary conditions. For Category 2, Problem 2, it is the internal radiation boundary conditions inside the duct. For Category 3, Problem 2, they are the inflow and outflow boundary conditions upstream and downstream of the blade row. These are the foci of the present investigation. Special nonhomogeneous radiation boundary conditions that generate the incoming disturbances and at the same time allow the outgoing reflected or scattered acoustic disturbances to leave the computation domain without significant reflection are developed. Numerical results based on these boundary conditions are provided.

  1. Comet solutions to a stylized BWR benchmark problem

    SciTech Connect

    Zhang, D.; Rahnema, F.

    2012-07-01

    In this paper, a stylized 3-D BWR benchmark problem was used to evaluate the performance of the coarse mesh radiation transport method COMET. The benchmark problem consists of 560 fuel bundles at 3 different burnups and 3 coolant void states. The COMET solution was compared with the corresponding Monte Carlo reference solution using the same 2-group material cross section library for three control blade (rod) configurations, namely, all rods out (ARO), all rods in (ARI) and some rods in (SRJ). The differences in the COMET and MCNP eigenvalues were 43 pcm, 66 pcm and 32 pcm for the ARO, ARI and SRI cases, respectively. These differences are all within 3 standard deviations of the COMET uncertainty. The average relative differences in the bundle averaged fission densities for these three cases were 0.89%, 1.24%, and 1.05%, respectively. The corresponding differences in the fuel pin averaged fission densities were 1.24%, 1.84% and 1.29%, respectively. It was found that COMET is 3,000 times faster than Monte Carlo, while its statistical uncertainty in the fuel pin fission density is much lower than that of Monte Carlo (i.e., {approx}40 times lower). (authors)

  2. A Benchmark Problem for Development of Autonomous Structural Modal Identification

    NASA Technical Reports Server (NTRS)

    Pappa, Richard S.; Woodard, Stanley E.; Juang, Jer-Nan

    1996-01-01

    This paper summarizes modal identification results obtained using an autonomous version of the Eigensystem Realization Algorithm on a dynamically complex, laboratory structure. The benchmark problem uses 48 of 768 free-decay responses measured in a complete modal survey test. The true modal parameters of the structure are well known from two previous, independent investigations. Without user involvement, the autonomous data analysis identified 24 to 33 structural modes with good to excellent accuracy in 62 seconds of CPU time (on a DEC Alpha 4000 computer). The modal identification technique described in the paper is the baseline algorithm for NASA's Autonomous Dynamics Determination (ADD) experiment scheduled to fly on International Space Station assembly flights in 1997-1999.

  3. Robustness of solutions to a benchmark control problem

    NASA Technical Reports Server (NTRS)

    Stengel, Robert F.; Marrison, Christopher I.

    1992-01-01

    The robustness of 10 solutions to a benchmark control design problem presented at the 1990 American Control Conference has been evaluated. The 10 controllers have second-to-eighth-order transfer functions and have been designed using several different methods, including H-infinity optimization, loop-transfer recovery, imaginary-axis shifting, constrained optimization, structured covariance, game theory, and the internal model principle. Stochastic robustness analysis quantifies the controllers' stability and performance robustness with structured uncertainties in up to six system parameters. The analysis provides insights into system response that are not readily derived from other robustness criteria and provides a common ground for judging controllers produced by alternative methods. One important conclusion is that gain and phase margins are not reliable indicators of the probability of instability. Furthermore, parameter variations actually may improve the likelihood of achieving selected performance metrics, as demonstrated by results for the probability of settling-time exceedance.

  4. Benchmark on Anisotropic Problems Numerical investigation of a mimetic finite difference method

    E-print Network

    Cirpka, Olaf Arie

    Benchmark on Anisotropic Problems Numerical investigation of a mimetic finite difference method@iws.uni-stuttgart.de ABSTRACT. This benchmark study investigates the behavior of a mimetic finite difference method. It solves the majority of the proposed problems with convincing accuracy and robustness. It appears to be most promising

  5. Identification of significant problems related to light water reactor piping systems

    SciTech Connect

    1980-07-01

    Work on the project was divided into three tasks. In Task 1, past surveys of LWR piping system problems and recent Licensee Event Report summaries are studied to identify the significant problems of LWR piping systems and the primary causes of these problems. Pipe cracking is identified as the most recurring problem and is mainly due to the vibration of pipes due to operating pump-pipe resonance, fluid-flow fluctuations, and vibration of pipe supports. Research relevant to the identified piping system problems is evaluated. Task 2 studies identify typical LWR piping systems and the current loads and load combinations used in the design of these systems. Definitions of loads are reviewed. In Task 3, a comparative study is carried out on the use of nonlinear analysis methods in the design of LWR piping systems. The study concludes that the current linear-elastic methods of analysis may not predict accurately the behavior of piping systems under seismic loads and may, under certain circumstances, result in nonconservative designs. Gaps at piping supports are found to have a significant effect on the response of the piping systems.

  6. COMET solutions to whole core CANDU-6 benchmark problems

    SciTech Connect

    Forget, B.; Rahnema, F.

    2006-07-01

    In this paper, the coarse mesh transport code COMET is used to solve CANDU-6 benchmark problems in two and three dimensional geometry. These problems are representative of a simplified quarter core reactor model. The COMET solutions, the core eigenvalue and the fuel pin fission density distribution, are compared to those from the Monte Carlo code MCNP using two-group cross sections. COMET decomposes the core volume into a set of non-overlapping sub-volumes (coarse meshes) and uses pre-computed heterogeneous response functions that are constructed using Legendre polynomials as boundary conditions to generate a user selected whole core solution (e.g., the core eigenvalue and fuel pin fission density distribution). These response functions are pre-computed by performing fixed source calculations with a modified version of MCNP in only the unique coarse meshes in the core. Reference solutions are calculated by MCNP5 with a two-group energy library generated with the HELIOS lattice code. In the 2-D problem, the angular current on the coarse mesh interfaces in COMET is expanded to 2. order in both spatial and angular variables. The COMET eigenvalue error is 0.09%. The corresponding average error in the fission density over all 3515 fuel pins is 0.5%. The maximum error observed is 2.0%. For the 3-D case, with 4. order expansion in space and azimuthal angle and 2. order expansion in the cosine of the polar angle, the eigenvalue differs from the reference solution by 0.05%. The average fission density error over the 42180 fuel pins is 0.7% with a maximum error of 3.3%. (authors)

  7. A BENCHMARK PROGRAM FOR EVALUATION OF METHODS FOR COMPUTING SEISMIC RESPONSE OF COUPLED BUILDING-PIPING/EQUIPMENT WITH NON-CLASSICAL DAMPING.

    SciTech Connect

    Xu, J.; Degrassi, G.; Chokshi, N.

    2001-03-22

    Under the auspices of the US Nuclear Regulatory Commission (NRC), Brookhaven National Laboratory (BNL) developed a comprehensive program to evaluate state-of-the-art methods and computer programs for seismic analysis of typical coupled nuclear power plant (NPP) systems with nonclassical damping. In this program, four benchmark models of coupled building-piping/equipment systems with different damping characteristics were analyzed for a suite of earthquakes by program participants applying their uniquely developed methods and computer programs. This paper presents the results of their analyses, and their comparison to the benchmark solutions generated by BNL using time domain direct integration methods. The participant's analysis results established using complex modal time history methods showed good comparison with the BNL solutions, while the analyses produced with either complex-mode response spectrum methods or classical normal-mode response spectrum method, in general, produced more conservative results, when averaged over a suite of earthquakes. However, when coupling due to damping is significant, complex-mode response spectrum methods performed better than the classical normal-mode response spectrum method. Furthermore, as part of the program objectives, a parametric assessment is also presented in this paper, aimed at evaluation of the applicability of various analysis methods to problems with different dynamic characteristics unique to coupled NPP systems. It is believed that the findings and insights learned from this program will be useful in developing new acceptance criteria and providing guidance for future regulatory activities involving licensing applications of these alternate methods to coupled systems.

  8. Error Analysis of Variations on Larsen's Benchmark Problem

    SciTech Connect

    Azmy, YY

    2001-06-27

    Error norms for three variants of Larsen's benchmark problem are evaluated using three numerical methods for solving the discrete ordinates approximation of the neutron transport equation in multidimensional Cartesian geometry. The three variants of Larsen's test problem are concerned with the incoming flux boundary conditions: unit incoming flux on the left and bottom edges (Larsen's configuration); unit, incoming flux only on the left edge; unit incoming flux only on the bottom edge. The three methods considered are the Diamond Difference (DD) method, and the constant-approximation versions of the Arbitrarily High Order Transport method of the Nodal type (AHOT-N), and of the Characteristic (AHOT-C) type. The cell-wise error is computed as the difference between the cell-averaged flux computed by each method and the exact value, then the L{sub 1}, L{sub 2}, and L{sub {infinity}} error norms are calculated. The results of this study demonstrate that while integral error norms, i.e. L{sub 1}, L{sub 2}, converge to zero with mesh refinement, the pointwise L{sub {infinity}} norm does not due to solution discontinuity across the singular characteristic. Little difference is observed between the error norm behavior of the three methods considered in spite of the fact that AHOT-C is locally exact, suggesting that numerical diffusion across the singular characteristic as the major source of error on the global scale. However, AHOT-C possesses a given accuracy in a larger fraction of computational cells than DD.

  9. Single pin BWR benchmark problem for coupled Monte Carlo - Thermal hydraulics analysis

    SciTech Connect

    Ivanov, A.; Sanchez, V.; Hoogenboom, J. E.

    2012-07-01

    As part of the European NURISP research project, a single pin BWR benchmark problem was defined. The aim of this initiative is to test the coupling strategies between Monte Carlo and subchannel codes developed by different project participants. In this paper the results obtained by the Delft Univ. of Technology and Karlsruhe Inst. of Technology will be presented. The benchmark problem was simulated with the following coupled codes: TRIPOLI-SUBCHANFLOW, MCNP-FLICA, MCNP-SUBCHANFLOW, and KENO-SUBCHANFLOW. (authors)

  10. Levermore-Pomraning Model Results for an Interior Source Binary Stochastic Medium Benchmark Problem

    SciTech Connect

    Brantley, P S; Palmer, T S

    2009-02-24

    The accuracy of the Levermore-Pomraning model for particle transport through a binary stochastic medium is investigated using an interior source benchmark problem. As in previous comparisons of the model for incident angular flux benchmark problems, the model accurately computes the leakage and the scalar flux distributions for optically thin slabs. The model is less accurate for more optically thick slabs but has a maximum relative error in the leakage of approximately 10% for the problems examined. The maximum root-mean-squared relative errors for the total and material scalar flux distributions approach 65% for the more optically thick slabs. Consistent with previous benchmark comparisons, the results of these interior source benchmark comparisons demonstrate that the Levermore-Pomraning model produces qualitatively correct and semi-quantitatively correct results for both leakage values and scalar flux distributions.

  11. HEATING6 analysis of international thermal benchmark problem sets 1 and 2

    SciTech Connect

    Childs, K.W.; Bryan, C.B.

    1986-10-01

    In order to assess the heat transfer computer codes used in the analysis of nuclear fuel shipping casks, the Nuclear Energy Agency Committee on Reactor Physics has defined seven problems for benchmarking thermal codes. All seven of these problems have been solved using the HEATING6 heat transfer code. This report presents the results of five of the problems. The remaining two problems were used in a previous benchmarking of thermal codes used in the United States, and their solutions have been previously published.

  12. Benchmarking Strategies for Measuring the Quality of Healthcare: Problems and Prospects

    PubMed Central

    Lovaglio, Pietro Giorgio

    2012-01-01

    Over the last few years, increasing attention has been directed toward the problems inherent to measuring the quality of healthcare and implementing benchmarking strategies. Besides offering accreditation and certification processes, recent approaches measure the performance of healthcare institutions in order to evaluate their effectiveness, defined as the capacity to provide treatment that modifies and improves the patient's state of health. This paper, dealing with hospital effectiveness, focuses on research methods for effectiveness analyses within a strategy comparing different healthcare institutions. The paper, after having introduced readers to the principle debates on benchmarking strategies, which depend on the perspective and type of indicators used, focuses on the methodological problems related to performing consistent benchmarking analyses. Particularly, statistical methods suitable for controlling case-mix, analyzing aggregate data, rare events, and continuous outcomes measured with error are examined. Specific challenges of benchmarking strategies, such as the risk of risk adjustment (case-mix fallacy, underreporting, risk of comparing noncomparable hospitals), selection bias, and possible strategies for the development of consistent benchmarking analyses, are discussed. Finally, to demonstrate the feasibility of the illustrated benchmarking strategies, an application focused on determining regional benchmarks for patient satisfaction (using 2009 Lombardy Region Patient Satisfaction Questionnaire) is proposed. PMID:22666140

  13. Semi-analytical solution to the 2014 eddy current benchmark problem

    NASA Astrophysics Data System (ADS)

    Miorelli, Roberto; Reboud, Christophe; Voulgaraki, Charitini; Poulakis, Nikolaos; Theodoulidis, Theodoros

    2015-03-01

    This work proposes a solution to the 2014 eddy current testing benchmark, published by the WFNDEC and proposed by the authors. The aim of this benchmark is to provide reference data for eddy current testing configurations involving magnetic sensors -here Hall sensors- as receivers, as they present some advantages in terms of resolution and sensitivity. After a presentation of the benchmark cases, the theoretical approach used to solve the equivalent electromagnetic problem is detailed and a alternative computation of eddy current signals is proposed. Then, simulations are quantitatively compared to experimental data in each case and the results are discussed.

  14. Comparison of Numerical Schemes for a Realistic Computational Aeroacoustics Benchmark Problem

    NASA Technical Reports Server (NTRS)

    Hixon, R.; Wu, J.; Nallasamy, M.; Sawyer, S.; Dyson, R.

    2004-01-01

    In this work, a nonlinear structured-multiblock CAA solver, the NASA GRC BASS code, will be tested on a realistic CAA benchmark problem. The purpose of this test is to ascertain what effect the high-accuracy solution methods used in CAA have on a realistic test problem, where both the mean flow and the unsteady waves are simultaneously computed on a fully curvilinear grid from a commercial grid generator. The proposed test will compare the solutions obtained using several finite-difference methods on identical grids to determine whether high-accuracy schemes have advantages for this benchmark problem.

  15. Benchmarking Problems Used in Second Year Level Organic Chemistry Instruction

    ERIC Educational Resources Information Center

    Raker, Jeffrey R.; Towns, Marcy H.

    2010-01-01

    Investigations of the problem types used in college-level general chemistry examinations have been reported in this Journal and were first reported in the "Journal of Chemical Education" in 1924. This study extends the findings from general chemistry to the problems of four college-level organic chemistry courses. Three problem typologies were

  16. Improving the worthiness of the Henry problem as a benchmark for density-dependent groundwater flow models

    E-print Network

    Clement, Prabhakar

    Improving the worthiness of the Henry problem as a benchmark for density-dependent groundwater flow), Improving the worthiness of the Henry problem as a benchmark for density- dependent groundwater flow models January 2004. [1] This study considers the worthiness of the Henry saltwater intrusion problem as a test

  17. Dependability Benchmarking & Prediction: A Grand Challenge Technology Problem

    E-print Network

    Koopman, Philip

    Problems, November 30, 1999; Phoenix, Arizona USA Philip Koopman ECE Department & ICES Carnegie Mellon University Pittsburgh, PA, USA koopman@cmu.edu Henrique Madeira Information Engineering Department

  18. Least-Squares Spectral Element Solutions to the CAA Workshop Benchmark Problems

    NASA Technical Reports Server (NTRS)

    Lin, Wen H.; Chan, Daniel C.

    1997-01-01

    This paper presents computed results for some of the CAA benchmark problems via the acoustic solver developed at Rocketdyne CFD Technology Center under the corporate agreement between Boeing North American, Inc. and NASA for the Aerospace Industry Technology Program. The calculations are considered as benchmark testing of the functionality, accuracy, and performance of the solver. Results of these computations demonstrate that the solver is capable of solving the propagation of aeroacoustic signals. Testing of sound generation and on more realistic problems is now pursued for the industrial applications of this solver. Numerical calculations were performed for the second problem of Category 1 of the current workshop problems for an acoustic pulse scattered from a rigid circular cylinder, and for two of the first CAA workshop problems, i. e., the first problem of Category 1 for the propagation of a linear wave and the first problem of Category 4 for an acoustic pulse reflected from a rigid wall in a uniform flow of Mach 0.5. The aim for including the last two problems in this workshop is to test the effectiveness of some boundary conditions set up in the solver. Numerical results of the last two benchmark problems have been compared with their corresponding exact solutions and the comparisons are excellent. This demonstrates the high fidelity of the solver in handling wave propagation problems. This feature lends the method quite attractive in developing a computational acoustic solver for calculating the aero/hydrodynamic noise in a violent flow environment.

  19. MHD and heat transfer benchmark problems for liquid metal flow in rectangular ducts. Final paper

    SciTech Connect

    Sidorenkov, S.I.; Hua, T.Q.; Araseki, Hideo

    1994-07-01

    Liquid metal cooling systems of a self-cooled blanket in a tokamak reactor will likely include channels of rectangular cross section where liquid metal is circulated in the presence of strong magnetic fields. MHD pressure drop, velocity distribution and heat transfer characteristics are important issues in the engineering design considerations. Computer codes for the reliable solution of three-dimensional MHD flow problems are needed for fusion relevant conditions. This paper describes four benchmark problems to validate magnetohydrodynamic (MHD) and heat transfer computer codes. The problems include rectangular duct geometry with uniform and nonuniform magnetic fields, with and without surface heat flux, and various rectangular cross sections. Two of the problems are based on experiments. Participants in this benchmarking activity come from three countries: The Russian Federation, The United States, and Japan. The solution methods to the problems are described. Results from the different computer codes are presented and compared.

  20. Benchmark Problem: A PK/PD Model and Safety Constraints for Anesthesia Delivery

    E-print Network

    Mitchell, Ian

    Benchmark Problem: A PK/PD Model and Safety Constraints for Anesthesia Delivery Victor Gan, Guy A of the goals of general anesthesia. In this brief paper we provide a differential equation model of how Introduction General anesthesia is a broad term encompassing the use of drugs to induce and maintain three

  1. Evaluation of a High-Accuracy MacCormack-Type Scheme Using Benchmark Problems

    NASA Technical Reports Server (NTRS)

    Hixon, R.

    1997-01-01

    Due to their inherent dissipation and stability, the MacCormack scheme and its variants have been widely used in the computation of unsteady flow and acoustic problems. However, these schemes require many points per wavelength in order to propagate waves with a reasonable amount of accuracy. In this work, the linear wave propagation characteristics of MacCormack-type schemes are shown by solving several of the CAA Benchmark Problems.

  2. Merton's problem for an investor with a benchmark in a Barndorff-Nielsen and Shephard market.

    PubMed

    Lennartsson, Jan; Lindberg, Carl

    2015-01-01

    To try to outperform an externally given benchmark with known weights is the most common equity mandate in the financial industry. For quantitative investors, this task is predominantly approached by optimizing their portfolios consecutively over short time horizons with one-period models. We seek in this paper to provide a theoretical justification to this practice when the underlying market is of Barndorff-Nielsen and Shephard type. This is done by verifying that an investor who seeks to maximize her expected terminal exponential utility of wealth in excess of her benchmark will in fact use an optimal portfolio equivalent to the one-period Markowitz mean-variance problem in continuum under the corresponding Black-Scholes market. Further, we can represent the solution to the optimization problem as in Feynman-Kac form. Hence, the problem, and its solution, is analogous to Merton's classical portfolio problem, with the main difference that Merton maximizes expected utility of terminal wealth, not wealth in excess of a benchmark. PMID:25774334

  3. PARTISN results for the C5G7 MOX benchmark problems

    SciTech Connect

    Dahl, J. A.; Alcouffe, Raymond E.

    2002-01-01

    In early 2001 the Nuclear Energy Agency solicited participants for a proposed new benchmark. The benchmark, known as C5G7 MOX, is intended to be a basis to measure current transport code abilities in the treatment of reactor core problems without spatial homogenization. We have participated with the code transport code PARTISN. PARTISN (PARallel TIme Dependent SN), PARTISN solves the linear Boltzmann transport equation in static and time dependent forms on one, two and three dimensional orthogonal grids using the deterministic (SN) method. A variety of spatial discritization methods are incorporated into PARTISN, however all calculations performed here used the diamond difference approach, coupled with a volume fraction method for non-Cartesian problem geometries. Acceleration of the source iterations is accomplished with diffusion synthetic acceleration (DSA).

  4. MC21 analysis of the nuclear energy agency Monte Carlo performance benchmark problem

    SciTech Connect

    Kelly, D. J.; Sutton, T. M.; Wilson, S. C.

    2012-07-01

    Due to the steadily decreasing cost and wider availability of large scale computing platforms, there is growing interest in the prospects for the use of Monte Carlo for reactor design calculations that are currently performed using few-group diffusion theory or other low-order methods. To facilitate the monitoring of the progress being made toward the goal of practical full-core reactor design calculations using Monte Carlo, a performance benchmark has been developed and made available through the Nuclear Energy Agency. A first analysis of this benchmark using the MC21 Monte Carlo code was reported on in 2010, and several practical difficulties were highlighted. In this paper, a newer version of MC21 that addresses some of these difficulties has been applied to the benchmark. In particular, the confidence-interval-determination method has been improved to eliminate source correlation bias, and a fission-source-weighting method has been implemented to provide a more uniform distribution of statistical uncertainties. In addition, the Forward-Weighted, Consistent-Adjoint-Driven Importance Sampling methodology has been applied to the benchmark problem. Results of several analyses using these methods are presented, as well as results from a very large calculation with statistical uncertainties that approach what is needed for design applications. (authors)

  5. The 2D Continuum Radiative Transfer Problem: Benchmark Results for Disk Configurations

    E-print Network

    I. Pascucci; S. Wolf; J. Steinacker; C. P. Dullemond; Th. Henning; G. Niccolini; P. Woitke; B. Lopez

    2004-02-15

    We present benchmark problems and solutions for the continuum radiative transfer (RT) in a 2D disk configuration. The reliability of three Monte-Carlo and two grid-based codes is tested by comparing their results for a set of well-defined cases which differ for optical depth and viewing angle. For all the configurations, the overall shape of the resulting temperature and spectral energy distribution is well reproduced. The solutions we provide can be used for the verification of other RT codes.We also point out the advantages and disadvantages of the various numerical techniques applied to solve the RT problem.

  6. Whole-core comet solutions to a 3-dimensional PWR benchmark problem with gadolinium

    SciTech Connect

    Zhang, D.; Rahnema, F.

    2012-07-01

    A pressurized water reactor (PWR) benchmark problem with gadolinium was used to determine the accuracy and computational efficiency of the coarse mesh radiation transport method COMET. The benchmark problem contains 193 square fuel assemblies. The COMET solution (eigenvalue, assembly averaged and fuel pin averaged fission density distributions) was compared with those obtained from the corresponding Monte Carlo reference solution using the same 2-group material cross section library. The comparison showed that both the core eigenvalue and fission density distribution averaged over each assembly and fuel pin predicated by COMET agree very well with the corresponding MCNP reference solution if the incident flux response expansion used in COMET is truncated at 2nd order in the two spatial and the two angular variables. The benchmark calculations indicate that COMET has Monte Carlo accuracy. In, particular, the eigenvalue difference between the codes ranged from 17 pcm to 35 pcm, being within 2 standard deviations of the calculational uncertainty. The mean flux weighted relative differences in the assembly and fuel pin fission densities were 0.47% and 0.65%, respectively. It was also found that COMET's full (whole) core computational speed is 30,000 times faster than MCNP in which only 1/8 of the core is modeled. It is estimated that COMET would have been about over 6 orders of magnitude faster than MCNP if the full core were also modeled in MCNP. (authors)

  7. Benchmark solutions for the galactic ion transport equations: Energy and spatially dependent problems

    NASA Technical Reports Server (NTRS)

    Ganapol, Barry D.; Townsend, Lawrence W.; Wilson, John W.

    1989-01-01

    Nontrivial benchmark solutions are developed for the galactic ion transport (GIT) equations in the straight-ahead approximation. These equations are used to predict potential radiation hazards in the upper atmosphere and in space. Two levels of difficulty are considered: (1) energy independent, and (2) spatially independent. The analysis emphasizes analytical methods never before applied to the GIT equations. Most of the representations derived have been numerically implemented and compared to more approximate calculations. Accurate ion fluxes are obtained (3 to 5 digits) for nontrivial sources. For monoenergetic beams, both accurate doses and fluxes are found. The benchmarks presented are useful in assessing the accuracy of transport algorithms designed to accommodate more complex radiation protection problems. In addition, these solutions can provide fast and accurate assessments of relatively simple shield configurations.

  8. TOPAZ - the transient one-dimensional pipe flow analyzer: code validation and sample problems

    SciTech Connect

    Winters, W.S.

    1985-10-01

    TOPAZ is a ''user friendly'' computer code for modeling the one-dimensional-transient physics of multi-species gas transfer in arbitrary arrangements of pipes, valves, vessels, and flow branches. This document presents a series of sample problems designed to aid potential users in creating TOPAZ input files. To the extent possible, sample problems were selected for which analytical solutions currently exist. TOPAZ comparisons with such solutions are intended to provide a measure of code validation.

  9. Benchmark Solution For The Category 3, Problem 2: Cascade - Gust Interaction

    NASA Technical Reports Server (NTRS)

    Envia, Edmane

    2004-01-01

    The benchmark solution for the cascade-gust interaction problem is computed using a linearized Euler code called LINFLUX. The inherently three-dimensional code is run in the thin-annulus limit to compute the two-dimensional cascade response. The calculations are carried out in the frequency-domain and the unsteady response at each of the gust s three frequency component is computed. The results are presented on modal basis for pressure perturbations (i.e., acoustic modes) as well as velocity perturbations (i.e., convected gust modes) at each frequency.

  10. On benchmark problems, challenges, and competitions in electrokinetics-A review.

    PubMed

    Hurk, Zden?k; Foret, Frantiek

    2015-07-01

    In this critical review, we comment on the absence of widely shared benchmark problems and relevant challenges or even attractive competitions in the field of electrokinetics. We argue that in some other scientific domains that are, similarly as electrokinetics, strongly multidisciplinary, the existence of these tools is very beneficial because it stimulates the discussion about what constitutes the bottleneck of further progress, allows easier exploitation of results provided by other scientific and engineering disciplines, and, last but not least, makes the research domain attractive and visible to a broader public, including students. The goal of this review is to provoke some discussion that might perhaps lead to compensating for these shortcomings. PMID:25820420

  11. Validation of Depth-Averaged Flow Model Using Flat-Bottomed Benchmark Problems

    PubMed Central

    Seo, Il Won; Kim, Young Do; Song, Chang Geun

    2014-01-01

    In this study, a shallow water flow code was developed and tested against four benchmark problems of practical relevance. The results demonstrated that as the eddy viscosity increased, the velocity slope along the spanwise direction decreased, and the larger roughness coefficient induced a higher flow depth over the channel width. The mass conservation rate was determined to be 99.2%. This value was measured by the variation of the total volume of the fluid after a cylinder break. As the Re increased to 10,000 in the internal recirculating flow problem, the intensity of the primary vortex had a clear trend toward the theoretically infinite Re value of ?1.886. The computed values of the supercritical flow evolved by the oblique hydraulic jump agreed well with the analytic solutions within an error bound of 0.2%. The present model adopts the nonconservative form of shallow water equations. These equations are weighted by the SU/PG scheme and integrated by a fully implicit method, which can reproduce physical problems with various properties. The model provides excellent results under various flow conditions, and the solutions of benchmark tests can present criteria for the evaluation of various algorithmic approaches. PMID:24982929

  12. A Study of Fixed-Order Mixed Norm Designs for a Benchmark Problem in Structural Control

    NASA Technical Reports Server (NTRS)

    Whorton, Mark S.; Calise, Anthony J.; Hsu, C. C.

    1998-01-01

    This study investigates the use of H2, p-synthesis, and mixed H2/mu methods to construct full-order controllers and optimized controllers of fixed dimensions. The benchmark problem definition is first extended to include uncertainty within the controller bandwidth in the form of parametric uncertainty representative of uncertainty in the natural frequencies of the design model. The sensitivity of H2 design to unmodelled dynamics and parametric uncertainty is evaluated for a range of controller levels of authority. Next, mu-synthesis methods are applied to design full-order compensators that are robust to both unmodelled dynamics and to parametric uncertainty. Finally, a set of mixed H2/mu compensators are designed which are optimized for a fixed compensator dimension. These mixed norm designs recover the H, design performance levels while providing the same levels of robust stability as the u designs. It is shown that designing with the mixed norm approach permits higher levels of controller authority for which the H, designs are destabilizing. The benchmark problem is that of an active tendon system. The controller designs are all based on the use of acceleration feedback.

  13. Integrating CFD, CAA, and Experiments Towards Benchmark Datasets for Airframe Noise Problems

    NASA Technical Reports Server (NTRS)

    Choudhari, Meelan M.; Yamamoto, Kazuomi

    2012-01-01

    Airframe noise corresponds to the acoustic radiation due to turbulent flow in the vicinity of airframe components such as high-lift devices and landing gears. The combination of geometric complexity, high Reynolds number turbulence, multiple regions of separation, and a strong coupling with adjacent physical components makes the problem of airframe noise highly challenging. Since 2010, the American Institute of Aeronautics and Astronautics has organized an ongoing series of workshops devoted to Benchmark Problems for Airframe Noise Computations (BANC). The BANC workshops are aimed at enabling a systematic progress in the understanding and high-fidelity predictions of airframe noise via collaborative investigations that integrate state of the art computational fluid dynamics, computational aeroacoustics, and in depth, holistic, and multifacility measurements targeting a selected set of canonical yet realistic configurations. This paper provides a brief summary of the BANC effort, including its technical objectives, strategy, and selective outcomes thus far.

  14. ICASE/LaRC Workshop on Benchmark Problems in Computational Aeroacoustics (CAA)

    NASA Technical Reports Server (NTRS)

    Hardin, Jay C. (editor); Ristorcelli, J. Ray (editor); Tam, Christopher K. W. (editor)

    1995-01-01

    The proceedings of the Benchmark Problems in Computational Aeroacoustics Workshop held at NASA Langley Research Center are the subject of this report. The purpose of the Workshop was to assess the utility of a number of numerical schemes in the context of the unusual requirements of aeroacoustical calculations. The schemes were assessed from the viewpoint of dispersion and dissipation -- issues important to long time integration and long distance propagation in aeroacoustics. Also investigated were the effect of implementation of different boundary conditions. The Workshop included a forum in which practical engineering problems related to computational aeroacoustics were discussed. This discussion took the form of a dialogue between an industrial panel and the workshop participants and was an effort to suggest the direction of evolution of this field in the context of current engineering needs.

  15. Performance of an elasto-viscoplastic model in some benchmark problems

    NASA Astrophysics Data System (ADS)

    Frey, Srgio L.; Naccache, Mnica F.; de Souza Mendes, Paulo R.; Thompson, Roney L.; dos Santos, Daniel D.; Link, Fernanda B.; Fonseca, Cleiton

    2015-08-01

    A recent elasto-viscoplastic thixotropic model proposed by (de Souza Mendes in J. Non-Newton. Fluid Mech. 164:66-75, 2009; de Souza Mendes in Soft Matter 7:2471-2483, 2011) is applied to five benchmark problems: the flow in a lid cavity, the flow through an expansion followed by a contraction, the flow over a flat plate, the channel entry flow, and the flow around a cylinder confined between parallel plates. One of the main advantages of this approach is its ability to recover a model for elasto-viscoplastic materials in a smooth fashion, i.e., in the limit where the characteristic thixotropic time tends to zero. These problems are numerically solved using the finite element method, with a four-field GLS-type formulation. While the simplified version is applied to the first three problems, the full model including thixotropy is applied to the channel entry flow and the flow around the cylinder. The elasto-viscoplastic problems analyzed show that, in general, elasticity tends to inhibit yielding and is more concentrated in unyielded regions. The thixotropic effects analyzed show that the delay in the microstructure response of the material significantly alters the problem when compared to the pure elasto-viscoplastic counterpart.

  16. OTEC cold water pipe design for problems caused by vortex-excited oscillations

    SciTech Connect

    Griffin, O. M.

    1980-03-14

    Vortex-excited oscillations of marine structures result in reduced fatigue life, large hydrodynamic forces and induced stresses, and sometimes lead to structural damage and to diestructive failures. The cold water pipe of an OTEC plant is nominally a bluff, flexible cylinder with a large aspect ratio (L/D = length/diameter), and is likely to be susceptible to resonant vortex-excited oscillations. The objective of this report is to survey recent results pertaining to the vortex-excited oscillations of structures in general and to consider the application of these findings to the design of the OTEC cold water pipe. Practical design calculations are given as examples throughout the various sections of the report. This report is limited in scope to the problems of vortex shedding from bluff, flexible structures in steady currents and the resulting vortex-excited oscillations. The effects of flow non-uniformities, surface roughness of the cylinder, and inclination to the incident flow are considered in addition to the case of a smooth cyliner in a uniform stream. Emphasis is placed upon design procedures, hydrodynamic coefficients applicable in practice, and the specification of structural response parameters relevant to the OTEC cold water pipe. There are important problems associated with in shedding of vortices from cylinders in waves and from the combined action of waves and currents, but these complex fluid/structure interactions are not considered in this report.

  17. C5 Benchmark Problem with Discrete Ordinate Radiation Transport Code DENOVO

    SciTech Connect

    Yesilyurt, Gokhan; Clarno, Kevin T; Evans, Thomas M; Davidson, Gregory G; Fox, Patricia B

    2011-01-01

    The C5 benchmark problem proposed by the Organisation for Economic Co-operation and Development/Nuclear Energy Agency was modeled to examine the capabilities of Denovo, a three-dimensional (3-D) parallel discrete ordinates (S{sub N}) radiation transport code, for problems with no spatial homogenization. Denovo uses state-of-the-art numerical methods to obtain accurate solutions to the Boltzmann transport equation. Problems were run in parallel on Jaguar, a high-performance supercomputer located at Oak Ridge National Laboratory. Both the two-dimensional (2-D) and 3-D configurations were analyzed, and the results were compared with the reference MCNP Monte Carlo calculations. For an additional comparison, SCALE/KENO-V.a Monte Carlo solutions were also included. In addition, a sensitivity analysis was performed for the optimal angular quadrature and mesh resolution for both the 2-D and 3-D infinite lattices of UO{sub 2} fuel pin cells. Denovo was verified with the C5 problem. The effective multiplication factors, pin powers, and assembly powers were found to be in good agreement with the reference MCNP and SCALE/KENO-V.a Monte Carlo calculations.

  18. A comparative study of upwind and MacCormack schemes for CAA benchmark problems

    NASA Technical Reports Server (NTRS)

    Viswanathan, K.; Sankar, L. N.

    1995-01-01

    In this study, upwind schemes and MacCormack schemes are evaluated as to their suitability for aeroacoustic applications. The governing equations are cast in a curvilinear coordinate system and discretized using finite volume concepts. A flux splitting procedure is used for the upwind schemes, where the signals crossing the cell faces are grouped into two categories: signals that bring information from outside into the cell, and signals that leave the cell. These signals may be computed in several ways, with the desired spatial and temporal accuracy achieved by choosing appropriate interpolating polynomials. The classical MacCormack schemes employed here are fourth order accurate in time and space. Results for categories 1, 4, and 6 of the workshop's benchmark problems are presented. Comparisons are also made with the exact solutions, where available. The main conclusions of this study are finally presented.

  19. Solutions of the benchmark problems by the dispersion-relation-preserving scheme

    NASA Technical Reports Server (NTRS)

    Tam, Christopher K. W.; Shen, H.; Kurbatskii, K. A.; Auriault, L.

    1995-01-01

    The 7-point stencil Dispersion-Relation-Preserving scheme of Tam and Webb is used to solve all the six categories of the CAA benchmark problems. The purpose is to show that the scheme is capable of solving linear, as well as nonlinear aeroacoustics problems accurately. Nonlinearities, inevitably, lead to the generation of spurious short wave length numerical waves. Often, these spurious waves would overwhelm the entire numerical solution. In this work, the spurious waves are removed by the addition of artificial selective damping terms to the discretized equations. Category 3 problems are for testing radiation and outflow boundary conditions. In solving these problems, the radiation and outflow boundary conditions of Tam and Webb are used. These conditions are derived from the asymptotic solutions of the linearized Euler equations. Category 4 problems involved solid walls. Here, the wall boundary conditions for high-order schemes of Tam and Dong are employed. These conditions require the use of one ghost value per boundary point per physical boundary condition. In the second problem of this category, the governing equations, when written in cylindrical coordinates, are singular along the axis of the radial coordinate. The proper boundary conditions at the axis are derived by applying the limiting process of r approaches 0 to the governing equations. The Category 5 problem deals with the numerical noise issue. In the present approach, the time-independent mean flow solution is computed first. Once the residual drops to the machine noise level, the incident sound wave is turned on gradually. The solution is marched in time until a time-periodic state is reached. No exact solution is known for the Category 6 problem. Because of this, the problem is formulated in two totally different ways, first as a scattering problem then as a direct simulation problem. There is good agreement between the two numerical solutions. This offers confidence in the computed results. Both formulations are solved as initial value problems. As such, no Kutta condition is required at the trailing edge of the airfoil.

  20. Evaluating Heat Pipe Performance in 1/6 g Acceleration: Problems and Prospects

    NASA Technical Reports Server (NTRS)

    Jaworske, Donald A.; McCollum, Timothy A.; Gibson, Marc A.; Sanzi, James L.; Sechkar, Edward A.

    2011-01-01

    Heat pipes composed of titanium and water are being considered for use in the heat rejection system of a fission power system option for lunar exploration. Placed vertically on the lunar surface, the heat pipes would operate as thermosyphons in the 1/6 g environment. The design of thermosyphons for such an application is determined, in part, by the flooding limit. Flooding is composed of two components, the thickness of the fluid film on the walls of the thermosyphon and the interaction of the fluid flow with the concurrent vapor counter flow. Both the fluid thickness contribution and interfacial shear contribution are inversely proportional to gravity. Hence, evaluating the performance of a thermosyphon in a 1 g environment on Earth may inadvertently lead to overestimating the performance of the same thermosyphon as experienced in the 1/6 g environment on the moon. Several concepts of varying complexity have been proposed for evaluating thermosyphon performance in reduced gravity, ranging from tilting the thermosyphons on Earth based on a cosine function, to flying heat pipes on a low-g aircraft. This paper summarizes the problems and prospects for evaluating thermosyphon performance in 1/6 g.

  1. Theoretical analysis of the worthiness of Henry and Elder problems as benchmarks of density-dependent groundwater

    E-print Network

    Clement, Prabhakar

    -dependent groundwater flow models M.J. Simpson a , T.P. Clement a,b,* a Centre for Water Research, Department the availability of benchmark problems for testing density-dependent groundwater models is limited, one should: Groundwater-modeling; Density-dependent flow; Unsaturated flow; Contaminant transport 1. Introduction

  2. Application of low dissipation and dispersion Runge-Kutta schemes to benchmark problems in computational aeroacoustics

    NASA Technical Reports Server (NTRS)

    Hu, F. Q.; Hussaini, M. Y.; Manthey, J.

    1995-01-01

    We investigate accurate and efficient time advancing methods for computational aeroacoustics, where non-dissipative and non-dispersive properties are of critical importance. Our analysis pertains to the application of Runge-Kutta methods to high-order finite difference discretization. In many CFD applications, multi-stage Runge-Kutta schemes have often been favored for their low storage requirements and relatively large stability limits. For computing acoustic waves, however, the stability consideration alone is not sufficient, since the Runge-Kutta schemes entail both dissipation and dispersion errors. The time step is now limited by the tolerable dissipation and dispersion errors in the computation. In the present paper, it is shown that if the traditional Runge-Kutta schemes are used for time advancing in acoustic problems, time steps greatly smaller than that allowed by the stability limit are necessary. Low Dissipation and Dispersion Runge-Kutta (LDDRK) schemes are proposed, based on an optimization that minimizes the dissipation and dispersion errors for wave propagation. Optimizations of both single-step and two-step alternating schemes are considered. The proposed LDDRK schemes are remarkably more efficient than the classical Runge-Kutta schemes for acoustic computations. Numerical results of each Category of the Benchmark Problems are presented. Moreover, low storage implementations of the optimized schemes are discussed. Special issues of implementing numerical boundary conditions in the LDDRK schemes are also addressed.

  3. Application of PML Absorbing Boundary Conditions to the Benchmark Problems of Computational Aeroacoustics

    NASA Technical Reports Server (NTRS)

    Hu, Fang Q.; Manthey, Joe L.

    1997-01-01

    Accurate numerical non-reflecting boundary conditions are important in all the proposed benchmark problems of the Second Workshop. Recently, a new absorbing boundary condition has been developed using Perfectly Matched Layer (PML) equations for the Euler equations. In this approach, a region with a width of a few grid points is introduced adjacent to the non-reflecting boundaries. In the added region, Perfectly Matched Layer equations are constructed and applied so that the out-going waves are absorbed inside the layer with little reflection to the interior domain. It will be demonstrated in the present paper that the proposed absorbing boundary condition is quite general and versatile, applicable to radiation boundaries as well as inflow and outflow boundaries. It is also easy to implement. The emphasis of the paper will be on the application of the PML absorbing boundary condition to problems in Categories 1, 2, and 3. In Category 1, solutions of problems 1 and 2 are presented. Both problems are solved using a multi-domain polar grid system. Perfectly Matched Layer equations for a circular boundary are constructed and their effectiveness assessed. In Category 2, solutions of problem 2 are presented. Here, in addition to the radiation boundary conditions at the far field in the axisymmetric coordinate system, the inflow boundary condition at the duct inlet is also dealt with using the proposed Perfectly Match Layer equations. At the inlet, a PML domain is introduced in which the incident duct mode is simulated while the waves reflected from the open end of the duct are absorbed at the same time. In Category 3, solutions of all three problems are presented. Again, the PML absorbing boundary condition is used at the inflow boundary so that the incoming vorticity wave is simulated while the outgoing acoustic waves are absorbed with very little numerical reflection. All the problems are solved using central difference schemes for spatial discretizations and the optimized Low-Dissipation and Low-Dispersion Runge-Kutta scheme for the time integration. Issues of numerical accuracy and efficiency are also addressed.

  4. The 2004 Ultrasonic Benchmark Problem - SDH Response Under Oblique Incidence: Measurements and Patch Element Model Calculations

    SciTech Connect

    Krishnamurthy, C. V.; Shankar, M.; Vardhan, J. Vishnu; Balasubramaniam, Krishnan

    2006-03-06

    The 2004 ultrasonic benchmark problem requires models to predict, given a reference pulse waveform, the pulse echo response of cylindrical voids of various radii located in an elastic solid for various incidence angles of a transducer immersed in water. We present the results of calculations based on the patch element model, recently developed at CNDE, to determine the response of an SDH in aluminum for specific oblique incidence angles. Patch element model calculations for a scan across the SDH, involving a range of oblique incidence angles, are also presented. Measured pulse-echo scans involving the SDH response under oblique incidence conditions are reported. In addition, through transmission measurements involving a pinducer as a receiver and an immersion planar probe as a transmitter under oblique incidence conditions are also reported in a defect-free Aluminum block. These pinducer-based measurements on a defect-free block are utilised to characterize the fields at the chosen depth. Comparisons are made between predictions and measurements for the pulse-echo response of a SDH.

  5. On the eigenvalue problems of Poiseuille flows in a circular pipe

    NASA Astrophysics Data System (ADS)

    Maserumule, Motodi Samuel

    In this work we introduce a novel formulation of Sexl's equations obtained by expanding three dimensional infinitesimal disturbances about the axisymmetric Hagen-Poiseuille flow in a pipe of circular cross section. The formulation is based on a representation theorem of solenoidal vector fields due to Schmitt and von Wahl [53]. We use the new formulation to prove that the linear nonaxisymmetric eigenvalue problem associated with Hagen-Poiseuille flow has infinitely many eigenfunctions which form a complete set. The method of proof includes the DiPrima-Habetler completeness theorem [14]. A nontrivial transformation that links the new formulation with the formulation used by Salwen et al [50] is presented. The relationship between axisymmetric eigenfunctions associated with Hagen-Poiseuille flow and their counterparts associated with parabolic Poiseuille flow is explored by means of a numerical study. We use a modified Chebyshev tau numerical scheme to compute eigenvalues and eigenfunctions of the two problems. The parabolic Poiseuille flow is easier to deal with because of the absence of a singularity in the differential equations. An exact solution to the axisymmetric parabolic Poiseuille flow problem is presented for the first time.

  6. A Hydrochemical Hybrid Code for Astrophysical Problems. I. Code Verification and Benchmarks for a Photon-dominated Region (PDR)

    NASA Astrophysics Data System (ADS)

    Motoyama, Kazutaka; Morata, Oscar; Shang, Hsien; Krasnopolsky, Ruben; Hasegawa, Tatsuhiko

    2015-07-01

    A two-dimensional hydrochemical hybrid code, KM2, is constructed to deal with astrophysical problems that would require coupled hydrodynamical and chemical evolution. The code assumes axisymmetry in a cylindrical coordinate system and consists of two modules: a hydrodynamics module and a chemistry module. The hydrodynamics module solves hydrodynamics using a Godunov-type finite volume scheme and treats included chemical species as passively advected scalars. The chemistry module implicitly solves nonequilibrium chemistry and change of energy due to thermal processes with transfer of external ultraviolet radiation. Self-shielding effects on photodissociation of CO and H2 are included. In this introductory paper, the adopted numerical method is presented, along with code verifications using the hydrodynamics module and a benchmark on the chemistry module with reactions specific to a photon-dominated region (PDR). Finally, as an example of the expected capability, the hydrochemical evolution of a PDR is presented based on the PDR benchmark.

  7. Mesoscale Benchmark Demonstration Problem 1: Mesoscale Simulations of Intra-granular Fission Gas Bubbles in UO2 under Post-irradiation Thermal Annealing

    SciTech Connect

    Li, Yulan; Hu, Shenyang Y.; Montgomery, Robert; Gao, Fei; Sun, Xin; Tonks, Michael; Biner, Bullent; Millet, Paul; Tikare, Veena; Radhakrishnan, Balasubramaniam; Andersson , David

    2012-04-11

    A study was conducted to evaluate the capabilities of different numerical methods used to represent microstructure behavior at the mesoscale for irradiated material using an idealized benchmark problem. The purpose of the mesoscale benchmark problem was to provide a common basis to assess several mesoscale methods with the objective of identifying the strengths and areas of improvement in the predictive modeling of microstructure evolution. In this work, mesoscale models (phase-field, Potts, and kinetic Monte Carlo) developed by PNNL, INL, SNL, and ORNL were used to calculate the evolution kinetics of intra-granular fission gas bubbles in UO2 fuel under post-irradiation thermal annealing conditions. The benchmark problem was constructed to include important microstructural evolution mechanisms on the kinetics of intra-granular fission gas bubble behavior such as the atomic diffusion of Xe atoms, U vacancies, and O vacancies, the effect of vacancy capture and emission from defects, and the elastic interaction of non-equilibrium gas bubbles. An idealized set of assumptions was imposed on the benchmark problem to simplify the mechanisms considered. The capability and numerical efficiency of different models are compared against selected experimental and simulation results. These comparisons find that the phase-field methods, by the nature of the free energy formulation, are able to represent a larger subset of the mechanisms influencing the intra-granular bubble growth and coarsening mechanisms in the idealized benchmark problem as compared to the Potts and kinetic Monte Carlo methods. It is recognized that the mesoscale benchmark problem as formulated does not specifically highlight the strengths of the discrete particle modeling used in the Potts and kinetic Monte Carlo methods. Future efforts are recommended to construct increasingly more complex mesoscale benchmark problems to further verify and validate the predictive capabilities of the mesoscale modeling methods used in this study.

  8. Summary of the Tandem Cylinder Solutions from the Benchmark Problems for Airframe Noise Computations-I Workshop

    NASA Technical Reports Server (NTRS)

    Lockard, David P.

    2011-01-01

    Fifteen submissions in the tandem cylinders category of the First Workshop on Benchmark problems for Airframe Noise Computations are summarized. Although the geometry is relatively simple, the problem involves complex physics. Researchers employed various block-structured, overset, unstructured and embedded Cartesian grid techniques and considerable computational resources to simulate the flow. The solutions are compared against each other and experimental data from 2 facilities. Overall, the simulations captured the gross features of the flow, but resolving all the details which would be necessary to compute the noise remains challenging. In particular, how to best simulate the effects of the experimental transition strip, and the associated high Reynolds number effects, was unclear. Furthermore, capturing the spanwise variation proved difficult.

  9. Application of the INSTANT-HPS PN Transport Code to the C5G7 Benchmark Problem

    SciTech Connect

    Y. Wang; H. Zhang; R. H. Szilard; R. C. Martineau

    2011-06-01

    INSTANT is the INL's next generation neutron transport solver to support high-fidelity multi-physics reactor simulation INSTANT is in continuous development to extend its capability Code is designed to take full advantage of middle to large cluster (10-1000 processors) Code is designed to focus on method adaptation while also mesh adaptation will be possible. It utilizes the most modern computing techniques to generate a neutronics tool of full-core transport calculations for reactor analysis and design. It can perform calculations on unstructured 2D/3D triangular, hexagonal and Cartesian geometries. Calculations can be easily extended to more geometries because of the independent mesh framework coded with the model Fortran. This code has a multigroup solver with thermal rebalance and Chebyshev acceleration. It employs second-order PN and Hybrid Finite Element method (PNHFEM) discretization scheme. Three different in-group solvers - preconditioned Conjugate Gradient (CG) method, preconditioned Generalized Minimal Residual Method (GMRES) and Red-Black iteration - have been implemented and parallelized with the spatial domain decomposition in the code. The input is managed with extensible markup language (XML) format. 3D variables including the flux distributions are outputted into VTK files, which can be visualized by tools such as VisIt and ParaView. An extension of the code named INSTANTHPS provides the capability to perform 3D heterogeneous transport calculations within fuel pins. C5G7 is an OECD/NEA benchmark problem created to test the ability of modern deterministic transport methods and codes to treat reactor core problems without spatial homogenization. This benchmark problem had been widely analyzed with various code packages. In this transaction, results of the applying the INSTANT-HPS code to the C5G7 problem are summarized.

  10. Analysis of chlorinated polyvinyl chloride pipe burst problems :Vasquez residence system inspection.

    SciTech Connect

    Black, Billy D.; Menicucci, David F.; Harrison, John

    2005-10-01

    This report documents the investigation regarding the failure of CPVC piping that was used to connect a solar hot water system to standard plumbing in a home. Details of the failure are described along with numerous pictures and diagrams. A potential failure mechanism is described and recommendations are outlined to prevent such a failure.

  11. Pipe Flow Simulation Software: A Team Approach to Solve an Engineering Education Problem.

    ERIC Educational Resources Information Center

    Engel, Renata S.; And Others

    1996-01-01

    A computer simulation program for use in the study of fluid mechanics is described. The package is an interactive tool to explore the fluid flow characteristics of a pipe system by manipulating the physical construction of the system. The motivation, software design requirements, and specific details on how its objectives were met are presented.

  12. A Hydrochemical Hybrid Code for Astrophysical Problems. I. Code Verification and Benchmarks for Photon-Dominated Region (PDR)

    E-print Network

    Motoyama, Kazutaka; Shang, Hsien; Krasnopolsky, Ruben; Hasegawa, Tatsuhiko

    2015-01-01

    A two dimensional hydrochemical hybrid code, KM2, is constructed to deal with astrophysical problems that would require coupled hydrodynamical and chemical evolution. The code assumes axisymmetry in cylindrical coordinate system, and consists of two modules: a hydrodynamics module and a chemistry module. The hydrodynamics module solves hydrodynamics using a Godunov-type finite volume scheme and treats included chemical species as passively advected scalars. The chemistry module implicitly solves non-equilibrium chemistry and change of the energy due to thermal processes with transfer of external ultraviolet radiation. Self-shielding effects on photodissociation of CO and H$_2$ are included. In this introductory paper, the adopted numerical method is presented, along with code verifications using the hydrodynamics modules, and a benchmark on the chemistry module with reactions specific to a photon-dominated region (PDR). Finally, as an example of the expected capability, the hydrochemical evolution of a PDR is...

  13. Benchmarking the SPHINX and CTH shock physics codes for three problems in ballistics

    SciTech Connect

    Wilson, L.T.; Hertel, E.; Schwalbe, L.; Wingate, C.

    1998-02-01

    The CTH Eulerian hydrocode, and the SPHINX smooth particle hydrodynamics (SPH) code were used to model a shock tube, two long rod penetrations into semi-infinite steel targets, and a long rod penetration into a spaced plate array. The results were then compared to experimental data. Both SPHINX and CTH modeled the one-dimensional shock tube problem well. Both codes did a reasonable job in modeling the outcome of the axisymmetric rod impact problem. Neither code correctly reproduced the depth of penetration in both experiments. In the 3-D problem, both codes reasonably replicated the penetration of the rod through the first plate. After this, however, the predictions of both codes began to diverge from the results seen in the experiment. In terms of computer resources, the run times are problem dependent, and are discussed in the text.

  14. Some major problems with existing models and terminology associated with kimberlite pipes from a volcanological perspective, and some suggestions

    NASA Astrophysics Data System (ADS)

    Cas, R. A. F.; Hayman, P.; Pittari, A.; Porritt, L.

    2008-06-01

    Five significant problems hinder advances in understanding of the volcanology of kimberlites: (1) kimberlite geology is very model driven; (2) a highly genetic terminology drives deposit or facies interpretation; (3) the effects of alteration on preserved depositional textures have been grossly underestimated; (4) the level of understanding of the physical process significance of preserved textures is limited; and, (5) some inferred processes and deposits are not based on actual, modern volcanological processes. These issues need to be addressed in order to advance understanding of kimberlite volcanological pipe forming processes and deposits. The traditional, steep-sided southern African pipe model (Class I) consists of a steep tapering pipe with a deep root zone, a middle diatreme zone and an upper crater zone (if preserved). Each zone is thought to be dominated by distinctive facies, respectively: hypabyssal kimberlite (HK, descriptively called here massive coherent porphyritic kimberlite), tuffisitic kimberlite breccia (TKB, descriptively here called massive, poorly sorted lapilli tuff) and crater zone facies, which include variably bedded pyroclastic kimberlite and resedimented and reworked volcaniclastic kimberlite (RVK). Porphyritic coherent kimberlite may, however, also be emplaced at different levels in the pipe, as later stage intrusions, as well as dykes in the surrounding country rock. The relationship between HK and TKB is not always clear. Sub-terranean fluidisation as an emplacement process is a largely unsubstantiated hypothesis; modern in-vent volcanological processes should initially be considered to explain observed deposits. Crater zone volcaniclastic deposits can occur within the diatreme zone of some pipes, indicating that the pipe was largely empty at the end of the eruption, and subsequently began to fill-in largely through resedimentation and sourcing of pyroclastic deposits from nearby vents. Classes II and III Canadian kimberlite models have a more factual, descriptive basis, but are still inadequately documented given the recency of their discovery. The diversity amongst kimberlite bodies suggests that a three-model classification is an over-simplification. Every kimberlite is altered to varying degrees, which is an intrinsic consequence of the ultrabasic composition of kimberlite and the in-vent context; few preserve original textures. The effects of syn- to post-emplacement alteration on original textures have not been adequately considered to date, and should be back-stripped to identify original textural elements and configurations. Applying sedimentological textural configurations as a guide to emplacement processes would be useful. The traditional terminology has many connotations about spatial position in pipe and of process. Perhaps the traditional terminology can be retained in the industrial situation as a general lithofacies-mining terminological scheme because it is so entrenched. However, for research purposes a more descriptive lithofacies terminology should be adopted to facilitate detailed understanding of deposit characteristics, important variations in these, and the process origins. For example every deposit of TKB is different in componentry, texture, or depositional structure. However, because so many deposits in many different pipes are called TKB, there is an implication that they are all similar and that similar processes were involved, which is far from clear.

  15. Constant-concentration boundary condition: Lessons from the HYDROCOIN variable-density groundwater benchmark problem

    USGS Publications Warehouse

    Konikow, L.F.; Sanford, W.E.; Campbell, P.J.

    1997-01-01

    In a solute-transport model, if a constant-concentration boundary condition is applied at a node in an active flow field, a solute flux can occur by both advective and dispersive processes. The potential for advective release is demonstrated by reexamining the Hydrologic Code Intercomparison (HYDROCOIN) project case 5 problem, which represents a salt dome overlain by a shallow groundwater system. The resulting flow field includes significant salinity and fluid density variations. Several independent teams simulated this problem using finite difference or finite element numerical models. We applied a method-of-characteristics model (MOCDENSE). The previous numerical implementations by HYDROCOIN teams of a constant-concentration boundary to represent salt release by lateral dispersion only (as stipulated in the original problem definition) was flawed because this boundary condition allows the release of salt into the flow field by both dispersion and advection. When the constant-concentration boundary is modified to allow salt release by dispersion only, significantly less salt is released into the flow field. The calculated brine distribution for case 5 depends very little on which numerical model is used, as long as the selected model is solving the proper equations. Instead, the accuracy of the solution depends strongly on the proper conceptualization of the problem, including the detailed design of the constant-concentration boundary condition. The importance and sensitivity to the manner of specification of this boundary does not appear to have been recognized previously in the analysis of this problem.

  16. Piping Connector

    NASA Technical Reports Server (NTRS)

    1993-01-01

    A complex of high pressure piping at Stennis Space Center carries rocket propellants and other fluids/gases through the Center's Component Test Facility. Conventional clamped connectors tend to leak when propellant lines are chilled to extremely low temperatures. Reflange, Inc. customized an existing piping connector to include a secondary seal more tolerant of severe thermal gradients for Stennis. The T-Con connector solved the problem, and the company is now marketing a commercial version that permits testing, monitoring or collecting any emissions that may escape the primary seal during severe thermal transition.

  17. Sensitivity of MCNP5 calculations for a spherical numerical benchmark problem to the angular scattering distributions for deuterium

    SciTech Connect

    Kozier, K. S.

    2006-07-01

    This paper examines the sensitivity of MCNP5 k{sub eff} results to various deuterium data files for a simple benchmark problem consisting of an 8.4-cm radius sphere of uranium surrounded by an annulus of deuterium at the nuclide number density corresponding to heavy water. This study was performed to help clarify why {Delta}k{sub eff} values of about 10 mk are obtained when different ENDF/B deuterium data files are used in simulations of critical experiments involving solutions of high-enrichment uranyl fluoride in heavy water, while simulations of low-leakage, heterogeneous critical lattices of natural-uranium fuel rods in heavy water show differences of <1 mk. The benchmark calculations were performed as a function of deuterium reflector thickness for several uranium compositions using deuterium ACE files derived from ENDF/B-VII.b1 (release beta 1), ENDF/B-VI.4 and JENDL-3.3, which differ primarily in the energy/angle distributions for elastic scattering <3.2 MeV. Calculations were also performed using modified ACE files having equiprobable cosine bin values in the centre-of-mass reference frame in a progressive manner with increasing energy. It was found that the {Delta}k{sub eff} values increased with deuterium reflector thickness and uranium enrichment. The studies using modified ACE files indicate that most of the reactivity differences arise at energies <1 MeV; hence, this energy range should be given priority if new scattering distribution measurements are undertaken. (authors)

  18. Applicability domains for classification problems: benchmarking of distance to models for AMES mutagenicity set

    EPA Science Inventory

    For QSAR and QSPR modeling of biological and physicochemical properties, estimating the accuracy of predictions is a critical problem. The distance to model (DM) can be defined as a metric that defines the similarity between the training set molecules and the test set compound ...

  19. Fully implicit solutions of the benchmark backward facing step problem using finite element discretization and inexact Newton's method

    SciTech Connect

    McHugh, P.R.; Knoll, D.A.

    1992-01-01

    A fully implicit solution algorithm based on Newton's method is used to solve the steady, incompressible Navier-Stokes and energy equations. An efficiently evaluated numerical Jacobian is used to simplify implementation, and mesh sequencing is used to increase the radius of convergence of the algorithm. We employ finite volume discretization using the power law scheme of Patankar to solve the benchmark backward facing step problem defined by the ASME K-12 Aerospace Heat Transfer Committee. LINPACK banded Gaussian elimination and the preconditioned transpose-free quasi-minimal residual (TFQMR) algorithm of Freund are studied as possible linear equation solvers. Implementation of the preconditioned TFQMR algorithm requires use of the switched evolution relaxation algorithm of Mulder and Van Leer to ensure convergence. The preconditioned TFQMR algorithm is more memory efficient than the direct solver, but our implementation is not as CPU efficient. Results show that for the level of grid refinement used, power law differencing was not adequate to yield the desired accuracy for this problem.

  20. Making Benchmark Testing Work

    ERIC Educational Resources Information Center

    Herman, Joan L.; Baker, Eva L.

    2005-01-01

    Many schools are moving to develop benchmark tests to monitor their students' progress toward state standards throughout the academic year. Benchmark tests can provide the ongoing information that schools need to guide instructional programs and to address student learning problems. The authors discuss six criteria that educators can use to

  1. MCNP neutron benchmarks

    SciTech Connect

    Hendricks, J.S.; Whalen, D.J.; Cardon, D.A.; Uhle, J.L.

    1991-10-08

    Over 50 neutron benchmark calculations have recently been completed as part of an ongoing program to validate the MCNP Monte Carlo radiation transport code. The new and significant aspects of this work are as follows: These calculations are the first attempt at a validation program for MCNP and the first official benchmarking of version 4 of the code. We believe the chosen set of benchmarks is a comprehensive set that may be useful for benchmarking other radiation transport codes and data libraries. These calculations provide insight into how well neutron transport calculations can be expected to model a wide variety of problems.

  2. The application of cost averaging techniques to robust control of the benchmark problem

    NASA Technical Reports Server (NTRS)

    Hagood, Nesbitt W.; Crawley, Edward F.

    1991-01-01

    A method is presented for the synthesis of robust controllers for linear time invariant systems with parameterized uncertainty structures. The method involves minimizing the average quadratic (H2) cost over the parameterized system. Bonded average cost implies stability over the set of systems. The average cost functional is minimized to derive robust fixed-order dynamic compensators. The robustness properties of these controllers are demonstrated on the sample problem.

  3. Robust H-infinity control synthesis method and its application to benchmark problems

    NASA Technical Reports Server (NTRS)

    Wie, Bong; Liu, Qiang; Byun, Kuk-Whan

    1992-01-01

    This paper presents a robust H-infinity control synthesis method for structured parameter uncertainty. The robust H-infinity control design methodology is also incorporated with the so-called internal model principle for persistent-disturbance rejection. A noncollocated control problem of flexible space structures subject to parameter variations is used to illustrate the design methodology. It is shown that the proposed design method invariably makes use of nonminimum-phase compensation and that it achieves the desired asymptotic disturbance rejection by having a disturbance rejection 'dipole'.

  4. A new pipe element for modeling three-dimensional large deformation problems

    SciTech Connect

    Arabyan, A.; Jiang, Y.

    1995-12-31

    A new straight pipe element that enables the efficient computation of large, three-dimensional deformations in pipes with circular cross-sections is presented. The new element, which supports rigid-body and constant-strain (RC) modes, is modeled using curvilinear shell coordinates and sinusoidal interpolation functions and captures all stresses except the normal stress across the shell thickness (i.e. small thickness is assumed). Euler parameters are used to describe rotational rigid-body modes and are incorporated into the element`s vector of degrees of freedom. Under general loading (axial, transverse, bending and torsion), the element allows large ovalization of its cross section and large, three-dimensional, angular changes in the orientation of its reference axis. The formulation used to derive the element incorporates the nonlinear coupling between torsional and bending deformations. Results are presented for the stresses and deformations produced by combined bending and torsional loads. A comparison of these results to corresponding quantities generated by ABAQUS using a large number of 24 degree-of-freedom shell elements indicates excellent agreement and significant gains in computational efficiency because of a reduction in number of degrees of freedom.

  5. Benchmarking Global Optimization and Constraint Satisfaction Codes

    E-print Network

    Neumaier, Arnold

    , but currently most problems on this site are without computational results. Our benchmark includes a large part of the problems from these two projects. All problems in our benchmark are represented in a common format suitable collections of benchmarking problems as particular cases, #15; checked for consistence, #15; annotated

  6. Benchmarking Global Optimization and Constraint Satisfaction Codes

    E-print Network

    Neumaier, Arnold

    , but currently most problems on this site are without computational results. Our benchmark includes a large part of the problems from these two projects. All problems in our benchmark are represented in a common format suitable satisfaction, · including most problems from the more restricted traditional collections of benchmarking

  7. ENDF/B-V and ENDF/B-VI results for UO{sub 2} lattice benchmark problems using MCNP

    SciTech Connect

    Mosteller, R.D.

    1998-12-31

    Calculations for the ANS UO{sub 2} lattice benchmark have been performed with the MCNP Monte Carlo code and its ENDF/B-V and ENDF/B-VI continuous-energy libraries. The ENDF/B-V library produces significantly better agreement with the benchmark value for k{sub eff} than do the ENDF/B-VI libraries. However, the pin power distributions are essentially the same irrespective of the library.

  8. Course Title Credits Critical Benchmark(s) Strongly Recommended CO 150 College Composition (AUCC 1A) 3

    E-print Network

    Beveridge, Ross

    Benchmark(s) Strongly Recommended SOC 100 General Sociology (AUCC 3C) 3 or SOC 105 Social Problems (AUCC 3CCourse Title Credits Critical Benchmark(s) Strongly Recommended CO 150 College Composition (AUCC 1A Benchmark(s) Strongly Recommended AUCC 3A Biological and Physical Sciences 3 AUCC 3B Arts and Humanities 3

  9. The ILTP Library: Benchmarking Automated Theorem Provers for Intuitionistic Logic

    E-print Network

    Otten, Jens

    The ILTP Library: Benchmarking Automated Theorem Provers for Intuitionistic Logic Thomas Raths Jens Theorem Proving (ILTP) Library provides a platfom for testing and benchmarking theorem provers for first problems. 1 Introduction Benchmarking automated theorem proving (ATP) systems using standardised problem

  10. NAS parallel benchmark results

    NASA Technical Reports Server (NTRS)

    Bailey, D. H.; Barszcz, E.; Dagum, L.; Simon, H. D.

    1992-01-01

    The NAS (Numerical Aerodynamic Simulation) parallel benchmarks have been developed at NASA Ames Research Center to study the performance of parallel supercomputers. The eight benchmark problems are specified in a 'pencil and paper' fashion. The performance results of various systems using the NAS parallel benchmarks are presented. These results represent the best results that have been reported to the authors for the specific systems listed. They represent implementation efforts performed by personnel in both the NAS Applied Research Branch of NASA Ames Research Center and in other organizations.

  11. ENDF/B-V and ENDF/B-VI results for UO-2 lattice benchmark problems using MCNP

    SciTech Connect

    Mosteller, R.D.

    1998-08-01

    Calculations for the ANS UO{sub 2} lattice benchmark have been performed with the MCNP Monte Carlo code and its ENDF/B-V and EnDF/B-VI continuous-energy libraries. Similar calculations were performed previously for the experiments upon which these benchmarks are based, using continuous-energy libraries derived from EnDF/B-V and from Release 2 of EnDF/B-VI (ENDF/B-VI.2). This study extends those calculations to the infinite-lattice configurations given in the benchmark specifications and also includes results from Release 3 of EnDF/B-VI (ENDF/B-VI.3) for both the core and infinite-lattice configurations. For this set of benchmarks, the only significant difference between the ENDF/B-VI.2 and EnDF/B-VI.3 libraries is the cross-section behavior of {sup 235}U. EnDF/B-VI.3 contains revised cross sections for {sup 235}U below 900 eV, although those changes principally affect the range below 110 eV. In particular, relative to EnDF/B-VI.2, EnDF/B-VI.3 increases the epithermal capture-to-fission ratio for {sup 235}U and slightly increases its thermal fission cross section.

  12. Model Predictive Control of Wind-Excited Building: Benchmark Study

    E-print Network

    Kareem, Ahsan

    modifications related to these benchmark problems and were launched as ``third generation'' benchmark problems-excited tall building Yang et al. 2000 . This paper investigates the ``third generation'' benchmark problemModel Predictive Control of Wind-Excited Building: Benchmark Study Gang Mei, A.M.ASCE1 ; Ahsan

  13. Genetic Programming Needs Better Benchmarks James McDermott

    E-print Network

    Luke, Sean

    ) is not a field noted for the rigor of its benchmarking. Some of its benchmark problems are popular purely through, domain-specific problems, the fundamental com- parison and analysis literature typically uses benchmark problems that are often very simple. We argue that such benchmarks do little to move the field forward

  14. DRAINAGE PIPE DETECTOR

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One of the more frustrating problems confronting farmers and land improvement contractors in the Midwestern United States involves locating buried agricultural drainage pipes. Conventional geophysical methods, particularly ground penetrating radar (GPR), presently being used for environmental and co...

  15. Course Title Credits Critical Benchmark(s) Strongly Recommended ANTH 120 Human Origins and Variation 3

    E-print Network

    Beveridge, Ross

    Course Title Credits Critical Benchmark(s) Strongly Recommended ANTH 120 Human Origins SOC 100 General Sociology 3 or SOC 105 Social Problems 3 Electives 3 Total Credits: 1516 Course Title Credits Critical Benchmark(s) Strongly Recommended HDFS 101 Individual and Family Development 3 HDFS 101

  16. Hg supply piping simulation Stony Brook University

    E-print Network

    McDonald, Kirk

    Stress Model", Int. J. Numer. Meth. Fluids 2005; 47:14311449 #12;Hg supply piping in Muon Collider InletHg supply piping simulation (No MHD) Stony Brook University Yan Zhan Prof. Foluso Ladeinde July 2nd, 2010 #12;Outline Hg supply piping in Muon Collider Turbulence models for bend pipe flow Problems

  17. Comet whole-core solution to a stylized 3-dimensional pressurized water reactor benchmark problem with UO{sub 2}and MOX fuel

    SciTech Connect

    Zhang, D.; Rahnema, F.

    2012-07-01

    A stylized pressurized water reactor (PWR) benchmark problem with UO{sub 2} and MOX fuel was used to test the accuracy and efficiency of the coarse mesh radiation transport (COMET) code. The benchmark problem contains 125 fuel assemblies and 44,000 fuel pins. The COMET code was used to compute the core eigenvalue and assembly and pin power distributions for three core configurations. In these calculations, a set of tensor products of orthogonal polynomials were used to expand the neutron angular phase space distribution on the interfaces between coarse meshes. The COMET calculations were compared with the Monte Carlo code MCNP reference solutions using a recently published an 8-group material cross section library. The comparison showed both the core eigenvalues and assembly and pin power distributions predicated by COMET agree very well with the MCNP reference solution if the orders of the angular flux expansion in the two spatial variables and the polar and azimuth angles on the mesh boundaries are 4, 4, 2 and 2. The mean and maximum differences in the pin fission density distribution ranged from 0.28%-0.44% and 3.0%-5.5%, all within 3-sigma uncertainty of the MCNP solution. These comparisons indicate that COMET can achieve accuracy comparable to Monte Carlo. It was also found that COMET's computational speed is 450 times faster than MCNP. (authors)

  18. Pipe Dreams.

    ERIC Educational Resources Information Center

    Milshtein, Amy

    2002-01-01

    Discusses the importance of attention to plumbing in college facilities, offering examples from various campuses. Addresses preventive maintenance, technology, and piping materials, including the debate between cast iron and PVC for drain pipes. (EV)

  19. Heat Pipes

    ERIC Educational Resources Information Center

    Lewis, J.

    1975-01-01

    Describes the construction, function, and applications of heat pipes. Suggests using the heat pipe to teach principles related to heat transfer and gives sources for obtaining instructional kits for this purpose. (GS)

  20. Testing (Validating?) Cross Sections with ICSBEP Benchmarks

    SciTech Connect

    Kahler, Albert C. III

    2012-06-28

    We discuss how to use critical benchmarks from the International Handbook of Evaluated Criticality Safety Benchmark Experiments to determine the applicability of specific cross sections to the end-user's problem of interest. Particular attention is paid to making sure the selected suite of benchmarks includes the user's range of applicability (ROA).

  1. AClib: a Benchmark Library for Algorithm Configuration

    E-print Network

    Schaub, Torsten

    AClib: a Benchmark Library for Algorithm Configuration Frank Hutter1 , Manuel L´opez-Ib´a~nez2 literature has developed automated approaches for this algorithm configu- ration problem [3, and benchmarks. Such a benchmark library would encourage reproducible research, facilitate the empirical

  2. AClib: a Benchmark Library for Algorithm Configuration

    E-print Network

    Hutter, Frank

    AClib: a Benchmark Library for Algorithm Configuration Frank Hutter1 , Manuel L´opez-Ib´a~nez2 literature has developed automated approaches for this algorithm config- uration problem [3, and benchmarks. Such a benchmark library would encourage reproducible research, facilitate the empirical

  3. AClib: A Benchmark Library for Algorithm Configuration

    E-print Network

    Hoos, Holger H.

    AClib: A Benchmark Library for Algorithm Configuration Frank Hutter1(B) , Manuel L´opez-Ib´a~nez2 such highly parameterized algorithms, recent work in the AI literature has developed automated approaches for standardized problem defin- itions, interfaces, and benchmarks. Such a benchmark library would encourage

  4. Applications of the Space-Time Conservation Element and Solution Element (CE/SE) Method to Computational Aeroacoustic Benchmark Problems

    NASA Technical Reports Server (NTRS)

    Wang, Xiao-Yen; Himansu, Ananda; Chang, Sin-Chung; Jorgenson, Philip C. E.

    2000-01-01

    The Internal Propagation problems, Fan Noise problem, and Turbomachinery Noise problems are solved using the space-time conservation element and solution element (CE/SE) method. The problems in internal propagation problems address the propagation of sound waves through a nozzle. Both the nonlinear and linear quasi 1D Euler equations are solved. Numerical solutions are presented and compared with the analytical solution. The fan noise problem concerns the effect of the sweep angle on the acoustic field generated by the interaction of a convected gust with a cascade of 3D flat plates. A parallel version of the 3D CE/SE Euler solver is developed and employed to obtain numerical solutions for a family of swept flat plates. Numerical solutions for sweep angles of 0, 5, 10, and 15 deg are presented. The turbomachinery problems describe the interaction of a 2D vortical gust with a cascade of flat-plate airfoils with/without a downstream moving grid. The 2D nonlinear Euler Equations are solved and the converged numerical solutions are presented and compared with the corresponding analytical solution. All the comparisons demonstrate that the CE/SE method is capable of solving aeroacoustic problems with/without shock waves in a simple and efficient manner. Furthermore, the simple non-reflecting boundary condition used in the CE/SE method which is not based on the characteristic theory works very well in 1D, 2D and 3D problems.

  5. An investigation of the origin of Rock City and cause of piping problems at Mountain Lake, Giles County, Virginia

    NASA Astrophysics Data System (ADS)

    Atallah, Nidal Walid

    Mountain Lake is one of only two natural lakes in the state of Virginia. The lake's origin has been attributed to either a natural solution-collapse basin, or to a landslide damming the valley of northwesterly flowing Pond Drain, or to a NW-SE trending fracture lineation. The lake is located within the breached northwest limb of a gently plunging anticline, a part of the larger Valley and Ridge physiographic province. In recent years, the lake drained almost completely, exposing the lake bottom and revealing the presence of four sinkhole-like depressions, containing piping holes at their sides and bottoms, at the northeastern and northwestern margins of the lake. This study focuses on the most likely origin of large sandstone blocks present at the northern end of the lake in an area locally referred to as "Rock City", including mapping of the block locations and analyzing the mode and extent of displacement that they have undergone. An additional objective is to investigate the piping potential of the lake-bottom sediment and its role in seepage out of the lake basin causing lake-level fluctuations. Mapping of Rock City was conducted by taking GPS readings at the corners of the rock blocks and using ArcMap Software. Investigations of the displacement mode of the rock blocks was done by comparing the measured orientations of principal discontinuity sets, forming the rock-block boundaries, with discontinuity orientations of undisturbed outcrops within the headscarp, using stereonet analysis. Grain size analysis, Atterberg limits, and a compaction-mold permeameter test were used to evaluate lake sediment's susceptibility to piping. Field observations and discontinuity data analysis indicate that Rock City is a landslide that dammed the valley of Pond Drain, consequently forming the lake. The primary mode of slope movement involves lateral spreading that is associated with extension occurring along discontinuities. The Tuscarora Sandstone rock blocks comprising Rock City were detached from the scarp face along a northwest-southeast trending joint set and were displaced laterally towards the west. A seismic event appears to be the most likely triggering mechanism for slope movement. Laboratory testing reveals that lake-bottom sediment is susceptible to piping, which is the primary mechanism responsible for the formation of the lake-bed depressions and lake-levels fluctuations. Grain size analysis reveals that lake-bottom sediment consists predominantly of fine sand and silt, both of which are highly susceptible to piping. Results of the compaction-mold permeameter test show that the hydraulic gradient at which lake-bottom sediment starts to pipe, the critical hydraulic gradient, ranges between 1 and 10, depending on the density, grain size distribution and cohesive properties of the sediment.

  6. NAS Parallel Benchmarks Results

    NASA Technical Reports Server (NTRS)

    Subhash, Saini; Bailey, David H.; Lasinski, T. A. (Technical Monitor)

    1995-01-01

    The NAS Parallel Benchmarks (NPB) were developed in 1991 at NASA Ames Research Center to study the performance of parallel supercomputers. The eight benchmark problems are specified in a pencil and paper fashion i.e. the complete details of the problem to be solved are given in a technical document, and except for a few restrictions, benchmarkers are free to select the language constructs and implementation techniques best suited for a particular system. In this paper, we present new NPB performance results for the following systems: (a) Parallel-Vector Processors: Cray C90, Cray T'90 and Fujitsu VPP500; (b) Highly Parallel Processors: Cray T3D, IBM SP2 and IBM SP-TN2 (Thin Nodes 2); (c) Symmetric Multiprocessing Processors: Convex Exemplar SPP1000, Cray J90, DEC Alpha Server 8400 5/300, and SGI Power Challenge XL. We also present sustained performance per dollar for Class B LU, SP and BT benchmarks. We also mention NAS future plans of NPB.

  7. Applications of Integral Benchmark Data

    SciTech Connect

    Giuseppe Palmiotti; Teruhiko Kugo; Fitz Trumble; Albert C. Kahler; Dale Lancaster

    2014-10-09

    The International Reactor Physics Experiment Evaluation Project (IRPhEP) and the International Criticality Safety Benchmark Evaluation Project (ICSBEP) provide evaluated integral benchmark data that may be used for validation of reactor physics / nuclear criticality safety analytical methods and data, nuclear data testing, advanced modeling and simulation, and safety analysis licensing activities. The handbooks produced by these programs are used in over 30 countries. Five example applications are presented in this paper: (1) Use of IRPhEP Data in Uncertainty Analyses and Cross Section Adjustment, (2) Uncertainty Evaluation Methods for Reactor Core Design at JAEA Using Reactor Physics Experimental Data, (3) Application of Benchmarking Data to a Broad Range of Criticality Safety Problems, (4) Cross Section Data Testing with ICSBEP Benchmarks, and (5) Use of the International Handbook of Evaluated Reactor Physics Benchmark Experiments to Support the Power Industry.

  8. Heat Pipes

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Phoenix Refrigeration Systems, Inc.'s heat pipe addition to the Phoenix 2000, a supermarket rooftop refrigeration/air conditioning system, resulted from the company's participation in a field test of heat pipes. Originally developed by NASA to control temperatures in space electronic systems, the heat pipe is a simple, effective, heat transfer system. It has been used successfully in candy storage facilities where it has provided significant energy savings. Additional data is expected to fully quantify the impact of the heat pipes on supermarket air conditioning systems.

  9. New DSP Benchmark based on Selectable Mode Vocoder (SMV)

    E-print Network

    Su, Bogong

    , these benchmarks are not without problems. For example, the BDTI 2000 benchmark of Berkeley Design Technology, IncNew DSP Benchmark based on Selectable Mode Vocoder (SMV) Erh-Wen Hu, Cyril S. Ku, Andrew T. Russo become larger and more complicated, people need new benchmarks for performance evaluation of different

  10. Experiencing with 007 Benchmark for Concurrency Control Technique Performance Evaluations

    E-print Network

    Gruenwald, Le

    discuss the problems and the possible suggestions for the 007 Benchmark, based on our experience, in terms techniques for each access type. In the paper, we report the problems of 007 benchmark during OODB. Especially, we discuss problems of the 007 benchmark, in terms of structures and operation (or transaction

  11. Piping Plover

    USGS Multimedia Gallery

    Chicks and eggs of piping plovers. The piping plover is a small migratory shorebird listed as endangered in Canada and the U.S. Great Lakes, and threatened throughout the remainder of its U.S. breeding and winter range. Recent surveys indicate that there are only about 8,000 adults in existence. Th...

  12. Piping Plover

    USGS Multimedia Gallery

    An adult piping plover. The piping plover is a small migratory shorebird listed as endangered in Canada and the U.S. Great Lakes, and threatened throughout the remainder of its U.S. breeding and winter range. Recent surveys indicate that there are only about 8,000 adults in existence. The USGS is co...

  13. Issues in Benchmark Metric Selection

    NASA Astrophysics Data System (ADS)

    Crolotte, Alain

    It is true that a metric can influence a benchmark but will esoteric metrics create more problems than they will solve? We answer this question affirmatively by examining the case of the TPC-D metric which used the much debated geometric mean for the single-stream test. We will show how a simple choice influenced the benchmark and its conduct and, to some extent, DBMS development. After examining other alternatives our conclusion is that the real measure for a decision-support benchmark is the arithmetic mean.

  14. Ultrasonic Benchmarking with UTDefect

    NASA Astrophysics Data System (ADS)

    Jansson, Per-A.?Ke; Bostrm, Anders

    2010-02-01

    UTDefect is a program for simulation of ultrasonic testing with emphasis on applications within the nuclear power industry. The entire testing process, including the ultrasonic transmitter, the receiver, and scattering from various types of defects of simple shape, is modelled. The basic idea behind UTDefect is to use solutions to the elastodynamic wave equation that are esentially exact. For the 2009 benchmark problems the results obtained from UTDefect are in most cases in fairly good agreement with the experimental data from CEA.

  15. Heat pipe dynamic behavior

    NASA Technical Reports Server (NTRS)

    Issacci, F.; Roche, G. L.; Klein, D. B.; Catton, I.

    1988-01-01

    The vapor flow in a heat pipe was mathematically modeled and the equations governing the transient behavior of the core were solved numerically. The modeled vapor flow is transient, axisymmetric (or two-dimensional) compressible viscous flow in a closed chamber. The two methods of solution are described. The more promising method failed (a mixed Galerkin finite difference method) whereas a more common finite difference method was successful. Preliminary results are presented showing that multi-dimensional flows need to be treated. A model of the liquid phase of a high temperature heat pipe was developed. The model is intended to be coupled to a vapor phase model for the complete solution of the heat pipe problem. The mathematical equations are formulated consistent with physical processes while allowing a computationally efficient solution. The model simulates time dependent characteristics of concern to the liquid phase including input phase change, output heat fluxes, liquid temperatures, container temperatures, liquid velocities, and liquid pressure. Preliminary results were obtained for two heat pipe startup cases. The heat pipe studied used lithium as the working fluid and an annular wick configuration. Recommendations for implementation based on the results obtained are presented. Experimental studies were initiated using a rectangular heat pipe. Both twin beam laser holography and laser Doppler anemometry were investigated. Preliminary experiments were completed and results are reported.

  16. Silicon Heat Pipe Array

    NASA Technical Reports Server (NTRS)

    Yee, Karl Y.; Ganapathi, Gani B.; Sunada, Eric T.; Bae, Youngsam; Miller, Jennifer R.; Beinsford, Daniel F.

    2013-01-01

    Improved methods of heat dissipation are required for modern, high-power density electronic systems. As increased functionality is progressively compacted into decreasing volumes, this need will be exacerbated. High-performance chip power is predicted to increase monotonically and rapidly with time. Systems utilizing these chips are currently reliant upon decades of old cooling technology. Heat pipes offer a solution to this problem. Heat pipes are passive, self-contained, two-phase heat dissipation devices. Heat conducted into the device through a wick structure converts the working fluid into a vapor, which then releases the heat via condensation after being transported away from the heat source. Heat pipes have high thermal conductivities, are inexpensive, and have been utilized in previous space missions. However, the cylindrical geometry of commercial heat pipes is a poor fit to the planar geometries of microelectronic assemblies, the copper that commercial heat pipes are typically constructed of is a poor CTE (coefficient of thermal expansion) match to the semiconductor die utilized in these assemblies, and the functionality and reliability of heat pipes in general is strongly dependent on the orientation of the assembly with respect to the gravity vector. What is needed is a planar, semiconductor-based heat pipe array that can be used for cooling of generic MCM (multichip module) assemblies that can also function in all orientations. Such a structure would not only have applications in the cooling of space electronics, but would have commercial applications as well (e.g. cooling of microprocessors and high-power laser diodes). This technology is an improvement over existing heat pipe designs due to the finer porosity of the wick, which enhances capillary pumping pressure, resulting in greater effective thermal conductivity and performance in any orientation with respect to the gravity vector. In addition, it is constructed of silicon, and thus is better suited for the cooling of semiconductor devices.

  17. Data-Intensive Benchmarking Suite

    Energy Science and Technology Software Center (ESTSC)

    2008-11-26

    The Data-Intensive Benchmark Suite is a set of programs written for the study of data-or storage-intensive science and engineering problems, The benchmark sets cover: general graph searching (basic and Hadoop Map/Reduce breadth-first search), genome sequence searching, HTTP request classification (basic and Hadoop Map/Reduce), low-level data communication, and storage device micro-beachmarking

  18. High temperature heat pipe experiments aboard the space shuttle

    SciTech Connect

    Woloshun, K.A.; Merrigan, M.A.; Sena, J.T. ); Secary, C.J. )

    1993-01-10

    Although high temperature, liquid metal heat pipe radiators have become a standard component on most space nuclear power systems, there is no experimental data on the operation of these heat pipes in a zero gravity or micro gravity environment. Experiments to benchmark the transient and steady state performance of prototypical heat pipe space radiator elements are in preparation. Three SST/potassium heat pipes are being designed, fabricated, and ground tested. It is anticipated that these heat pipes will fly aboard the space shuttle in 1995. Three wick structures will be tested: homogeneous, arterial, and annular gap. Ground tests are described that simulate the space shuttle environment in every way except gravity field.

  19. Interpolation and extrapolation problems of multivariate regression in analytical chemistry: benchmarking the robustness on near-infrared (NIR) spectroscopy data.

    PubMed

    Balabin, Roman M; Smirnov, Sergey V

    2012-04-01

    Modern analytical chemistry of industrial products is in need of rapid, robust, and cheap analytical methods to continuously monitor product quality parameters. For this reason, spectroscopic methods are often used to control the quality of industrial products in an on-line/in-line regime. Vibrational spectroscopy, including mid-infrared (MIR), Raman, and near-infrared (NIR), is one of the best ways to obtain information about the chemical structures and the quality coefficients of multicomponent mixtures. Together with chemometric algorithms and multivariate data analysis (MDA) methods, which were especially created for the analysis of complicated, noisy, and overlapping signals, NIR spectroscopy shows great results in terms of its accuracy, including classical prediction error, RMSEP. However, it is unclear whether the combined NIR + MDA methods are capable of dealing with much more complex interpolation or extrapolation problems that are inevitably present in real-world applications. In the current study, we try to make a rather general comparison of linear, such as partial least squares or projection to latent structures (PLS); "quasi-nonlinear", such as the polynomial version of PLS (Poly-PLS); and intrinsically non-linear, such as artificial neural networks (ANNs), support vector regression (SVR), and least-squares support vector machines (LS-SVM/LSSVM), regression methods in terms of their robustness. As a measure of robustness, we will try to estimate their accuracy when solving interpolation and extrapolation problems. Petroleum and biofuel (biodiesel) systems were chosen as representative examples of real-world samples. Six very different chemical systems that differed in complexity, composition, structure, and properties were studied; these systems were gasoline, ethanol-gasoline biofuel, diesel fuel, aromatic solutions of petroleum macromolecules, petroleum resins in benzene, and biodiesel. Eighteen different sample sets were used in total. General conclusions are made about the applicability of ANN- and SVM-based regression tools in the modern analytical chemistry. The effectiveness of different multivariate algorithms is different when going from classical accuracy to robustness. Neural networks, which are capable of producing very accurate results with respect to classical RMSEP, are not able to solve interpolation problems or, especially, extrapolation problems. The chemometric methods that are based on the support vector machine (SVM) ideology are capable of solving both classical regression and interpolation/extrapolation tasks. PMID:22337290

  20. High temperature heat pipe experiments in low earth orbit

    SciTech Connect

    Woloshun, K.; Merrigan, M.A.; Sena, J.T.; Critchley, E.

    1993-02-01

    Although high temperature, liquid metal heat pipe radiators have become a standard component on most high power space power system designs, there is no experimental data on the operation of these heat pipes in a zero gravity or micro-gravity environment. Experiments to benchmark the transient and steady state performance of prototypical heat pipe space radiator elements are in preparation for testing in low earth orbit. It is anticipated that these heat pipes will be tested aborad the Space Shuttle in 1995. Three heat pipes will be tested in a cargo bay Get Away Special (GAS) canister. The heat pipes are SST/potassium, each with a different wick structure; homogeneous, arterial, and annular gap, the heat pipes have been designed, fabricated, and ground tested. In this paper, the heat pipe designs are specified, and transient and steady-state ground test data are presented.

  1. Piping Analysis

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Burns & McDonnell provide architectural and engineering services in planning, design and construction of a wide range of projects all over the world. In design analysis, company regularly uses COSMIC computer programs. In computer testing piping design of a power plant, company uses Pipe Flexibility Analysis Program (MEL-21) to analyze stresses due to weight, temperature, and pressure found in proposed piping systems. Individual flow rates are put into the computer, then computer calculates the pressure drop existing across each component; if needed, design corrections or adjustments can be made and rechecked.

  2. Piping Flexibility

    NASA Technical Reports Server (NTRS)

    1978-01-01

    A NASA computer program aids Hudson Engineering Corporation, Houston, Texas, in the design and construction of huge petrochemical processing plants like the one shown, which is located at Ju'aymah, Saudi Arabia. The pipes handling the flow of chemicals are subject to a variety of stresses, such as weight and variations in pressure and temperature. Hudson Engineering uses a COSMIC piping flexibility analysis computer program to analyze stresses and unsure the necessary strength and flexibility of the pipes. This program helps the company realize substantial savings in reduced engineering time.

  3. Light pipes for LED measurements

    NASA Technical Reports Server (NTRS)

    Floyd, S. R.; Thomas, E. F., Jr.

    1976-01-01

    Light pipe directly couples LED optical output to single detector. Small area detector measures total optical output of diode. Technique eliminates thermal measurement problems and channels optical output to remote detector.

  4. Radiography benchmark 2014

    SciTech Connect

    Jaenisch, G.-R. Deresch, A. Bellon, C.; Schumm, A.; Lucet-Sanchez, F.; Guerin, P.

    2015-03-31

    The purpose of the 2014 WFNDEC RT benchmark study was to compare predictions of various models of radiographic techniques, in particular those that predict the contribution of scattered radiation. All calculations were carried out for homogenous materials and a mono-energetic X-ray point source in the energy range between 100 keV and 10 MeV. The calculations were to include the best physics approach available considering electron binding effects. Secondary effects like X-ray fluorescence and bremsstrahlung production were to be taken into account if possible. The problem to be considered had two parts. Part I examined the spectrum and the spatial distribution of radiation behind a single iron plate. Part II considered two equally sized plates, made of iron and aluminum respectively, only evaluating the spatial distribution. Here we present the results of above benchmark study, comparing them to MCNP as the assumed reference model. The possible origins of the observed deviations are discussed.

  5. Large-bore pipe decontamination

    SciTech Connect

    Ebadian, M.A.

    1998-01-01

    The decontamination and decommissioning (D and D) of 1200 buildings within the US Department of Energy-Office of Environmental Management (DOE-EM) Complex will require the disposition of miles of pipe. The disposition of large-bore pipe, in particular, presents difficulties in the area of decontamination and characterization. The pipe is potentially contaminated internally as well as externally. This situation requires a system capable of decontaminating and characterizing both the inside and outside of the pipe. Current decontamination and characterization systems are not designed for application to this geometry, making the direct disposal of piping systems necessary in many cases. The pipe often creates voids in the disposal cell, which requires the pipe to be cut in half or filled with a grout material. These methods are labor intensive and costly to perform on large volumes of pipe. Direct disposal does not take advantage of recycling, which could provide monetary dividends. To facilitate the decontamination and characterization of large-bore piping and thereby reduce the volume of piping required for disposal, a detailed analysis will be conducted to document the pipe remediation problem set; determine potential technologies to solve this remediation problem set; design and laboratory test potential decontamination and characterization technologies; fabricate a prototype system; provide a cost-benefit analysis of the proposed system; and transfer the technology to industry. This report summarizes the activities performed during fiscal year 1997 and describes the planned activities for fiscal year 1998. Accomplishments for FY97 include the development of the applicable and relevant and appropriate regulations, the screening of decontamination and characterization technologies, and the selection and initial design of the decontamination system.

  6. Unstructured Adaptive (UA) NAS Parallel Benchmark. Version 1.0

    NASA Technical Reports Server (NTRS)

    Feng, Huiyu; VanderWijngaart, Rob; Biswas, Rupak; Mavriplis, Catherine

    2004-01-01

    We present a complete specification of a new benchmark for measuring the performance of modern computer systems when solving scientific problems featuring irregular, dynamic memory accesses. It complements the existing NAS Parallel Benchmark suite. The benchmark involves the solution of a stylized heat transfer problem in a cubic domain, discretized on an adaptively refined, unstructured mesh.

  7. 7 CFR 1469.7 - Benchmark condition inventory and conservation stewardship plan.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 2012-01-01 false Benchmark condition inventory and conservation...Provisions 1469.7 Benchmark condition inventory and conservation...stewardship plan. (a) The benchmark condition inventory and associated...practices and resource concerns, problems, and opportunities on...

  8. 7 CFR 1469.7 - Benchmark condition inventory and conservation stewardship plan.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 2013-01-01 false Benchmark condition inventory and conservation...Provisions 1469.7 Benchmark condition inventory and conservation...stewardship plan. (a) The benchmark condition inventory and associated...practices and resource concerns, problems, and opportunities on...

  9. 7 CFR 1469.7 - Benchmark condition inventory and conservation stewardship plan.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 2010-01-01 false Benchmark condition inventory and conservation...Provisions 1469.7 Benchmark condition inventory and conservation...stewardship plan. (a) The benchmark condition inventory and associated...practices and resource concerns, problems, and opportunities on...

  10. 7 CFR 1469.7 - Benchmark condition inventory and conservation stewardship plan.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 2011-01-01 false Benchmark condition inventory and conservation...Provisions 1469.7 Benchmark condition inventory and conservation...stewardship plan. (a) The benchmark condition inventory and associated...practices and resource concerns, problems, and opportunities on...

  11. 7 CFR 1469.7 - Benchmark condition inventory and conservation stewardship plan.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 2014-01-01 false Benchmark condition inventory and conservation...Provisions 1469.7 Benchmark condition inventory and conservation...stewardship plan. (a) The benchmark condition inventory and associated...practices and resource concerns, problems, and opportunities on...

  12. CFD validation in OECD/NEA t-junction benchmark.

    SciTech Connect

    Obabko, A. V.; Fischer, P. F.; Tautges, T. J.; Karabasov, S.; Goloviznin, V. M.; Zaytsev, M. A.; Chudanov, V. V.; Pervichko, V. A.; Aksenova, A. E.

    2011-08-23

    When streams of rapidly moving flow merge in a T-junction, the potential arises for large oscillations at the scale of the diameter, D, with a period scaling as O(D/U), where U is the characteristic flow velocity. If the streams are of different temperatures, the oscillations result in experimental fluctuations (thermal striping) at the pipe wall in the outlet branch that can accelerate thermal-mechanical fatigue and ultimately cause pipe failure. The importance of this phenomenon has prompted the nuclear energy modeling and simulation community to establish a benchmark to test the ability of computational fluid dynamics (CFD) codes to predict thermal striping. The benchmark is based on thermal and velocity data measured in an experiment designed specifically for this purpose. Thermal striping is intrinsically unsteady and hence not accessible to steady state simulation approaches such as steady state Reynolds-averaged Navier-Stokes (RANS) models.1 Consequently, one must consider either unsteady RANS or large eddy simulation (LES). This report compares the results for three LES codes: Nek5000, developed at Argonne National Laboratory (USA), and Cabaret and Conv3D, developed at the Moscow Institute of Nuclear Energy Safety at (IBRAE) in Russia. Nek5000 is based on the spectral element method (SEM), which is a high-order weighted residual technique that combines the geometric flexibility of the finite element method (FEM) with the tensor-product efficiencies of spectral methods. Cabaret is a 'compact accurately boundary-adjusting high-resolution technique' for fluid dynamics simulation. The method is second-order accurate on nonuniform grids in space and time, and has a small dispersion error and computational stencil defined within one space-time cell. The scheme is equipped with a conservative nonlinear correction procedure based on the maximum principle. CONV3D is based on the immersed boundary method and is validated on a wide set of the experimental and benchmark data. The numerical scheme has a very small scheme diffusion and is the second and the first order accurate in space and time, correspondingly. We compare and contrast simulation results for three computational fluid dynamics codes CABARET, Conv3D, and Nek5000 for the T-junction thermal striping problem that was the focus of a recent OECD/NEA blind benchmark. The corresponding codes utilize finite-difference implicit large eddy simulation (ILES), finite-volume LES on fully staggered grids, and an LES spectral element method (SEM), respectively. The simulations results are in a good agreement with experimenatl data. We present results from a study of sensitivity to computational mesh and time integration interval, and discuss the next steps in the simulation of this problem.

  13. Silicate globules in kyanite from grospydites of the Zagadochnaya kimberlite pipe, Yakutia: The problem of the origin

    NASA Astrophysics Data System (ADS)

    Tomilenko, A. A.; Kovyazin, S. V.; Pokhilenko, L. N.; Sobolev, N. V.

    2011-01-01

    The results of complex study of silicate globules and ?-quartz paramorphs after coesite in kyanite from grospydites from the Zagadochnaya kimberlite pipe, Yakutia, using optical and scanning electron spectroscopy, electron and ion microprobes, LA ICP MS and Raman spectroscopy, are presented. The existence of radial fractures diverging from silicate globules into the matrix (kyanite) attests to the fact that the content of the globules is extremely condensed. A zonal structure is usually typical for globules: a coat and a core, which can be explicitly distinguished under the electron microscope, can be differentiated in them. Compositionally, the coat of the globule corresponds to potassium feldspar (wt %: 66.4 SiO2; 16.9 Al2O3; 0.4 FeO; 0.1 CaO; 0.2 Na2O; 14.7 K2O). The globules were also detected in which along with K, a high content of Na and Ca was also ascertained in the silicate coat. The globule coat is considerably enriched with Ba, La, Ce, Nb, and a number of other noncompatible elements as compared with xenolith minerals. The water content in globules is 0.6 wt %. As compared with the host mineral (kyanite), the core part of the globules is also enriched with Co, Ni, Zn, and Cu; their content in kyanite is negligibly low. The entire data collection attests to the fact that the formation of silicate globules could have been caused by interaction of the conservated fluid and/or water-silicate melt with the host mineral and crystalline inclusions of clinopyroxene and garnet with decreasing pressure during the transportation of grospydite xenoliths by the kimberlite melt to the Earth's surface.

  14. Heat Pipes

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Bobs Candies, Inc. produces some 24 million pounds of candy a year, much of it 'Christmas candy.' To meet Christmas demand, it must produce year-round. Thousands of cases of candy must be stored a good part of the year in two huge warehouses. The candy is very sensitive to temperature. The warehouses must be maintained at temperatures of 78-80 degrees Fahrenheit with relative humidities of 38- 42 percent. Such precise climate control of enormous buildings can be very expensive. In 1985, energy costs for the single warehouse ran to more than $57,000 for the year. NASA and the Florida Solar Energy Center (FSEC) were adapting heat pipe technology to control humidity in building environments. The heat pipes handle the jobs of precooling and reheating without using energy. The company contacted a FSEC systems engineer and from that contact eventually emerged a cooperative test project to install a heat pipe system at Bobs' warehouses, operate it for a period of time to determine accurately the cost benefits, and gather data applicable to development of future heat pipe systems. Installation was completed in mid-1987 and data collection is still in progress. In 1989, total energy cost for two warehouses, with the heat pipes complementing the air conditioning system was $28,706, and that figures out to a cost reduction.

  15. Radiation Detection Computational Benchmark Scenarios

    SciTech Connect

    Shaver, Mark W.; Casella, Andrew M.; Wittman, Richard S.; McDonald, Ben S.

    2013-09-24

    Modeling forms an important component of radiation detection development, allowing for testing of new detector designs, evaluation of existing equipment against a wide variety of potential threat sources, and assessing operation performance of radiation detection systems. This can, however, result in large and complex scenarios which are time consuming to model. A variety of approaches to radiation transport modeling exist with complementary strengths and weaknesses for different problems. This variety of approaches, and the development of promising new tools (such as ORNLs ADVANTG) which combine benefits of multiple approaches, illustrates the need for a means of evaluating or comparing different techniques for radiation detection problems. This report presents a set of 9 benchmark problems for comparing different types of radiation transport calculations, identifying appropriate tools for classes of problems, and testing and guiding the development of new methods. The benchmarks were drawn primarily from existing or previous calculations with a preference for scenarios which include experimental data, or otherwise have results with a high level of confidence, are non-sensitive, and represent problem sets of interest to NA-22. From a technical perspective, the benchmarks were chosen to span a range of difficulty and to include gamma transport, neutron transport, or both and represent different important physical processes and a range of sensitivity to angular or energy fidelity. Following benchmark identification, existing information about geometry, measurements, and previous calculations were assembled. Monte Carlo results (MCNP decks) were reviewed or created and re-run in order to attain accurate computational times and to verify agreement with experimental data, when present. Benchmark information was then conveyed to ORNL in order to guide testing and development of hybrid calculations. The results of those ADVANTG calculations were then sent to PNNL for compilation. This is a report describing the details of the selected Benchmarks and results from various transport codes.

  16. Piping Connector

    NASA Technical Reports Server (NTRS)

    1994-01-01

    In Stennis Space Center's Component Test Facility, piping lines carry rocket propellants and high pressure cryogenic fuels. When the lines are chilled to a pretest temperature of 400 degrees below zero, ordinary piping connectors can leak. Under contract to Stennis, Reflange, Inc. developed the T-Con connector, which included a secondary seal that tolerates severe temperature change. Because of the limited need for the large and expensive T-Con product, Reflange also developed the less costly E-Con, a smaller more compact design with the same technical advantages as the T-Con.

  17. IEEE TRANSACTIONS ON SOFTWARE ENGINEERING, VOL. X, 201X 1 The ManyBugs and IntroClass Benchmarks for

    E-print Network

    Brun, Yuriy

    repair lacks a set of common benchmark problems. Although benchmark sets are used widely throughout computer science, existing benchmarks are not easily adapted to the problem of automatic defect repair this last problem through the use of standardized benchmark problems, e.g., [5], [8], [75]. A well

  18. IEEE TRANSACTIONS ON SOFTWARE ENGINEERING, VOL. X, 201X 1 The ManyBugs and IntroClass Benchmarks for

    E-print Network

    Weimer, Westley

    repair lacks a set of common benchmark problems. Although benchmark sets are used widely throughout computer science, existing benchmarks are not easily adapted to the problem of automatic defect repair this last problem through the use of standardized benchmark problems, e.g., [10], [13], [72]. A well

  19. The NAS Parallel Benchmarks

    SciTech Connect

    Bailey, David H.

    2009-11-15

    The NAS Parallel Benchmarks (NPB) are a suite of parallel computer performance benchmarks. They were originally developed at the NASA Ames Research Center in 1991 to assess high-end parallel supercomputers. Although they are no longer used as widely as they once were for comparing high-end system performance, they continue to be studied and analyzed a great deal in the high-performance computing community. The acronym 'NAS' originally stood for the Numerical Aeronautical Simulation Program at NASA Ames. The name of this organization was subsequently changed to the Numerical Aerospace Simulation Program, and more recently to the NASA Advanced Supercomputing Center, although the acronym remains 'NAS.' The developers of the original NPB suite were David H. Bailey, Eric Barszcz, John Barton, David Browning, Russell Carter, LeoDagum, Rod Fatoohi, Samuel Fineberg, Paul Frederickson, Thomas Lasinski, Rob Schreiber, Horst Simon, V. Venkatakrishnan and Sisira Weeratunga. The original NAS Parallel Benchmarks consisted of eight individual benchmark problems, each of which focused on some aspect of scientific computing. The principal focus was in computational aerophysics, although most of these benchmarks have much broader relevance, since in a much larger sense they are typical of many real-world scientific computing applications. The NPB suite grew out of the need for a more rational procedure to select new supercomputers for acquisition by NASA. The emergence of commercially available highly parallel computer systems in the late 1980s offered an attractive alternative to parallel vector supercomputers that had been the mainstay of high-end scientific computing. However, the introduction of highly parallel systems was accompanied by a regrettable level of hype, not only on the part of the commercial vendors but even, in some cases, by scientists using the systems. As a result, it was difficult to discern whether the new systems offered any fundamental performance advantage over vector supercomputers, and, if so, which of the parallel offerings would be most useful in real-world scientific computation. In part to draw attention to some of the performance reporting abuses prevalent at the time, the present author wrote a humorous essay 'Twelve Ways to Fool the Masses,' which described in a light-hearted way a number of the questionable ways in which both vendor marketing people and scientists were inflating and distorting their performance results. All of this underscored the need for an objective and scientifically defensible measure to compare performance on these systems.

  20. Heat Pipes For Alyeska

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The heat pipes job is to keep the arctic ground frozen. The permafrost soil alternately freezes and thaws with seasonal temperature changes causing surface dislocations and problems for the builders. In winter, a phenomenon called frost-heaving uplifts the soil. It is something like the creation of highway potholes by the freezing of rainwater below the roadbed, but frost-heaving exerts a far greater force. Thawing of the frost in the summer causes the soil to settle unevenly. Therefore it is necessary to keep the soil in a continually frozen state so the pipeline won't rupture. To solve this problem, McDonnell Douglas Corp. applied heat pipe principles in the design of the vertical supports that hold up the pipeline.

  1. Heat Pipe Systems

    NASA Technical Reports Server (NTRS)

    1988-01-01

    Solar Fundamentals, Inc.'s hot water system employs space-derived heat pipe technology. It is used by a meat packing plant to heat water for cleaning processing machinery. Unit is complete system with water heater, hot water storage, electrical controls and auxiliary components. Other than fans and a circulating pump, there are no moving parts. System's unique design eliminates problems of balancing, leaking, corroding, and freezing.

  2. Evaluating Benchmark Subsetting Approaches Joshua J. Yi1

    E-print Network

    Minnesota, University of

    Evaluating Benchmark Subsetting Approaches Joshua J. Yi1 , Resit Sendag2 , Lieven Eeckhout3 , Ajay To reduce the simulation time to a tractable amount or due to compilation (or other related) problems, computer architects often simulate only a subset of the benchmarks in a benchmark suite. However

  3. The NAS parallel benchmarks

    NASA Technical Reports Server (NTRS)

    Bailey, David (editor); Barton, John (editor); Lasinski, Thomas (editor); Simon, Horst (editor)

    1993-01-01

    A new set of benchmarks was developed for the performance evaluation of highly parallel supercomputers. These benchmarks consist of a set of kernels, the 'Parallel Kernels,' and a simulated application benchmark. Together they mimic the computation and data movement characteristics of large scale computational fluid dynamics (CFD) applications. The principal distinguishing feature of these benchmarks is their 'pencil and paper' specification - all details of these benchmarks are specified only algorithmically. In this way many of the difficulties associated with conventional benchmarking approaches on highly parallel systems are avoided.

  4. Monitoring pipes for residual alpha contamination

    SciTech Connect

    MacArthur, D.; Rawool-Sullivan, M.; Dockray, T.

    1996-09-01

    The sensitivity and application of traditional alpha monitors is limited by the short range of alpha particles in air and in solid materials. Detecting small amounts of alpha-emitting contamination inside pipes presents particular problems. The alpha particle cannot penetrate the walls of the pipe. Associated gamma-ray detection and active neutron interrogation is often used to detect large amounts of radioactive material in pipes, but these methods are of limited use for detecting small amounts of contamination. Insertion of a traditional alpha probes works well in large diameter straight pipes, but is increasingly difficult as the pipe network becomes smaller in diameter and more complex. Monitors based on long-range alpha detection (LRAD) detect ionization of the ambient air rather than the alpha particles themselves. A small fan draws the ions into an externally mounted ion detector. Thus, the air in the pipe serves as both the detector gas and the mechanism for transporting the alpha-induced ions to a detection grid outside the pipe. All of the ions created by all of the contamination in the pipe can be measured in a single detector. Since ambient air serves as the probe, crushed or twisted sections of pipe can be monitored almost as effectively as straight sections. The pipe monitoring system described in the paper was tested both at LANL and BNFL`s Sellafield reprocessing facility in the UK. In this paper, we report on the first field tests of the pipe monitoring system.

  5. NASTRAN analysis of an air storage piping system

    NASA Technical Reports Server (NTRS)

    Young, C. P., Jr.; Gerringer, A. H.; Faison, R. W.

    1973-01-01

    The application of NASTRAN to a complex piping design evaluation problem is summarized. Emphasis is placed on structural modeling aspects, problems encountered in modeling and analyzing curved pipe sections, principal results, and relative merits of using NASTRAN as a pipe analysis and design tool. In addition, the piping and manifolding system was analyzed with SNAP (Structural Network Analysis Program). The parallel SNAP study provides a basis for limited comparisons between NASTRAN and SNAP as to solution agreement and computer execution time and costs.

  6. Soil response against oblique motion of pipes

    SciTech Connect

    Nyman, K.J.

    1984-03-01

    The proposed design procedures define the bilinear load-displacement relationships for soil restraint of buried pipes subjected to oblique horizontal-vertical motion. Arco derived these procedures from available theories on the behavior of soil restraint for inclined strip anchors, extending these mechanisms to the restraint of circular buried pipes. Typical pipeline design problems associated with this condition include restraint of out-of-place bends or combination bends where the net pipe thrust direction is oblique.

  7. Factory Flow Benchmarking Report

    E-print Network

    Shields, Thomas J.

    LAI benchmarked representative part fabrications and some assembly operations within its member companies of the defense aircraft industry. This paper reports the results of this benchmarking effort. In addition, this ...

  8. A steady state analysis code for prediction of behavior in loop heat pipes

    E-print Network

    Hamm, Trenton Allen

    1998-01-01

    The purpose of this work is to prepare an analysis raphics. code for the prediction of Loop Heat Pipe (LHP) behavior in steady-state operation. The FORTRAN program is then benchmarked with experimental data obtained in two orientations: 1...

  9. Flow conditions of fresh mortar and concrete in different pipes

    SciTech Connect

    Jacobsen, Stefan; Haugan, Lars; Hammer, Tor Arne; Kalogiannidis, Evangelos

    2009-11-15

    The variation in fresh concrete flow rate over the pipe cross section was investigated on differently coloured and highly flowable concrete mixes flowing through pipes of different materials (rubber, steel, acryl). First, uncoloured (gray) concrete was poured through the pipe and the pipe blocked. Similar but coloured (black) concrete was then poured into the pipe filled with gray concrete, flowing after the gray concrete for a while before being blocked and hardened. The advance of the colouring along the pipe wall (showing boundary flow rate) was observed on the moulded concrete surface appearing after removing the pipe from the hardened concrete. The shapes of the interfaces between uncoloured and coloured concrete (showing variation of flow rate over the pipe cross section) were observed on sawn surfaces of concrete half cylinders cut along the length axes of the concrete-filled pipe. Flow profiles over the pipe cross section were clearly seen with maximum flow rates near the centre of the pipe and low flow rate at the pipe wall (typically rubber pipe with reference concrete without silica fume and/or stabilizers). More plug-shaped profiles, with long slip layers and less variation of flow rate over the cross section, were also seen (typically in smooth acrylic pipes). Flow rate, amount of concrete sticking to the wall after flow and SEM-images of pipe surface roughness were observed, illustrating the problem of testing full scale pumping.

  10. The feasibility of electrohydrodynamic heat pipes

    NASA Technical Reports Server (NTRS)

    Jones, T. B.

    1971-01-01

    The effect of a nonuniform electrostatic field on insulating dielectric liquids in heat pipes was studied. Topics discussed include the theory of operation, design criteria, and evaluation of optimal design features. It is concluded that the electrodynamic heat pipes offer advantages that must be weighed against the disadvantages in order to arrive at a proper assessment of their value in solving heat transfer problems.

  11. Benchmarking your benchmarks: a user's perspective

    SciTech Connect

    Brice, R.

    1982-01-01

    This paper is intended for anyone faced with the responsibility for computer hardware or software selection. The content is biased toward administrative considerations, although some technical issues are presented. The basic goal is to promote a role for benchmarking in the computer acquisition process that is significantly broader than that commonly employed. We attempt to do this by showing how a thorough benchmarking effort (in the usual sense) did not provide sufficient information to accurately predict user satisfaction and productivity. We describe other measures of a system's properties that should be included in benchmarking.

  12. A performance benchmark test for geodynamo simulations

    NASA Astrophysics Data System (ADS)

    Matsui, H.; Heien, E. M.

    2013-12-01

    In the last ten years, a number of numerical dynamo models have successfully represented basic characteristics of the geomagnetic field. As new models and numerical methods continue to be developed, it is important to update and extend benchmarks for testing these models. The first dynamo benchmark of Christensen et al. (2001) was applied to models based on spherical harmonic expansion methods. However, only a few groups have reported results of the dynamo benchmark using local methods (Harder and Hansen, 2005; Matsui and Okuda, 2005; Chan et al., 2007) because of the difficulty treating magnetic boundary conditions based on the local methods. On the other hand, spherical harmonics expansion methods perform poorly on massively parallel computers because global data communications are required for the spherical harmonics expansions to evaluate nonlinear terms. We perform benchmark tests to asses various numerical methods for the next generation of geodynamo simulations. The purpose of this benchmark test is to assess numerical geodynamo models on a massively parallel computational platform. To compare among many numerical methods as possible, we consider the model with the insulated magnetic boundary by Christensen et al. (2001) and with the pseudo vacuum magnetic boundary, because the pseudo vacuum boundaries are implemented easier by using the local method than the magnetic insulated boundaries. In the present study, we consider two kinds of benchmarks, so-called accuracy benchmark and performance benchmark. In the accuracy benchmark, we compare the dynamo models by using modest Ekman and Rayleigh numbers proposed by Christensen et. al. (2001). We investigate a required spatial resolution for each dynamo code to obtain less than 1% difference from the suggested solution of the benchmark test using the two magnetic boundary conditions. In the performance benchmark, we investigate computational performance under the same computational environment. We perform these dynamo models on XSEDE TACC Stampede, and investigate computational performance. To simplify the problem, we choose the same model and parameter regime as the accuracy benchmark test, but perform the simulations with much finer spatial resolutions to investigate computational capability under the closer condition to the Earth's outer core. We compare the results of the accuracy benchmark and performance benchmark tests by various codes and discuss characteristics of the simulation methods for geodynamo problems.

  13. Benchmarking Interior Point LP/QP Solvers H. D. Mittelmann \\Lambda

    E-print Network

    Mittelmann, Hans D.

    benchmark was just added to [15]. The following IPM codes will be compared for LP problems: BPMPD, HOPDM and on the benchmarked codes follows next. The fourth and fifth sections deal with LP, respectively QP, problems, while convex QP problems in the benchmark

  14. The DARPA Image Understanding Motion Benchmark Charles Weems, Steven Dropsho, Glen Weaver, Rohan Kumar, James Burrill

    E-print Network

    Massachusetts at Amherst, University of

    of the cross formed by the two bars. The results obtained from solving the benchmark problem on various of the participants spent a fairly lengthy session discussing problems with the benchmark and designing a new benchmark that it was hoped would solve those problems. It was the perception of the Tanque Verde group

  15. GAPRUS -GENETIC ALGORITHMS BASED PIPE ROUTING USING TESSELLATED OBJECTS

    E-print Network

    Chen, Wei

    GAPRUS - GENETIC ALGORITHMS BASED PIPE ROUTING USING TESSELLATED OBJECTS Sunand Sandurkar Software problems involving 3D freeform obstacles is demonstrated. Key words: Pipe Routing, Genetic Algorithms of CAD model as a connected array of triangles (tessellated format) GAPRUS Genetic Algorithm based Pipe

  16. NAS Grid Benchmarks. 1.0

    NASA Technical Reports Server (NTRS)

    VanderWijngaart, Rob; Frumkin, Michael; Biegel, Bryan A. (Technical Monitor)

    2002-01-01

    We provide a paper-and-pencil specification of a benchmark suite for computational grids. It is based on the NAS (NASA Advanced Supercomputing) Parallel Benchmarks (NPB) and is called the NAS Grid Benchmarks (NGB). NGB problems are presented as data flow graphs encapsulating an instance of a slightly modified NPB task in each graph node, which communicates with other nodes by sending/receiving initialization data. Like NPB, NGB specifies several different classes (problem sizes). In this report we describe classes S, W, and A, and provide verification values for each. The implementor has the freedom to choose any language, grid environment, security model, fault tolerance/error correction mechanism, etc., as long as the resulting implementation passes the verification test and reports the turnaround time of the benchmark.

  17. PRISMATIC CORE COUPLED TRANSIENT BENCHMARK

    SciTech Connect

    J. Ortensi; M.A. Pope; G. Strydom; R.S. Sen; M.D. DeHart; H.D. Gougar; C. Ellis; A. Baxter; V. Seker; T.J. Downar; K. Vierow; K. Ivanov

    2011-06-01

    The Prismatic Modular Reactor (PMR) is one of the High Temperature Reactor (HTR) design concepts that have existed for some time. Several prismatic units have operated in the world (DRAGON, Fort St. Vrain, Peach Bottom) and one unit is still in operation (HTTR). The deterministic neutronics and thermal-fluids transient analysis tools and methods currently available for the design and analysis of PMRs have lagged behind the state of the art compared to LWR reactor technologies. This has motivated the development of more accurate and efficient tools for the design and safety evaluations of the PMR. In addition to the work invested in new methods, it is essential to develop appropriate benchmarks to verify and validate the new methods in computer codes. The purpose of this benchmark is to establish a well-defined problem, based on a common given set of data, to compare methods and tools in core simulation and thermal hydraulics analysis with a specific focus on transient events. The benchmark-working group is currently seeking OECD/NEA sponsorship. This benchmark is being pursued and is heavily based on the success of the PBMR-400 exercise.

  18. Task force reduces stuck-pipe costs

    SciTech Connect

    Bradley, W.B. ); Jarman, D. ); Auflick, R.A.; Plott, R.S. ); Wood, R.D. ); Schofield, T.R. ); Cocking, D. )

    1991-05-27

    A task-force approach to stuck pipe has produced more than a 70% reduction in BP Exploration Operating Co.'s worldwide stuck-pipe costs during 1989 and 1990. We believe that these results have been primarily due to focusing our attention on improving personnel performance rather than to the introduction of new technology. Key elements in this paper of the efforts involved: Recognizing the importance of the drilling contractor and the service company staff's role in helping control stuck pipe; Promoting a rig-team approach to tackling the problem; Providing training on rig-team, stuck-pipe problem solving; and raising awareness of stuck pipe through a coordinated worldwide communications program among BP, contractors, and service companies.

  19. Ultrasonic pipe assessment

    DOEpatents

    Thomas, Graham H.; Morrow, Valerie L.; Levie, Harold; Kane, Ronald J.; Brown, Albert E.

    2003-12-23

    An ultrasonic pipe or other structure assessment system includes an ultrasonic transducer positioned proximate the pipe or other structure. A fluid connection between the ultrasonic transducer and the pipe or other structure is produced. The ultrasonic transducer is moved relative to the pipe or other structure.

  20. Corrosion problem solutions for pipe and equipment during manufacture, fabrication, and storage using vapor corrosion inhibitors (VCI`s) and dry air

    SciTech Connect

    Gelner, L.

    1998-12-31

    This paper presents current technology and use of environmentally friendly, cost effective materials and techniques for pipe and equipment preservation. This includes the use of Temporary Inhibitor Coatings (TIC), Vapor Corrosion Inhibitors (VCI), and dehumidified air (DH). Materials are described in detail, and applications of each are discussed.

  1. Organ pipe resonance induced vibration in piping system

    SciTech Connect

    Wang, T.

    1996-12-01

    Acoustic-induced vibration is a fluid-structure interaction phenomenon. The feedback mechanism between the acoustic pressure pulsation and the structure movements determines the excited acoustic modes which, in turn, amplify the structure response when confidence frequency and mode shape matching occurs. The acoustic modes are not determined from the acoustic boundary conditions alone, structure feedback is as responsible for determining the acoustic modes and shaping the resulting forcing functions. Acoustic-induced piping vibration, when excited, does not attenuate much with distance. Pressure pulsation can be transmitted throughout the piping system and its branch connections. It is this property that makes vibration monitoring difficult, because vibration can surface at locations far away from the acoustic source when resonance occurs. For a large piping system with interconnected branches, the monitoring task can be formidable, particularly when there is no indication what the real source is. In organ pipe resonance induced vibration, the initiating acoustic source may be inconspicuous or unavoidable during operation. In these situations, the forcing function approach can offer an optimal tool for vibration assessment. The forcing function approach was used in the evaluation of a standby steam piping vibration problem. Monitoring locations and instrument specifications were determined from the acoustic eigenfunction profiles. Measured data confirmed the presence of coherent vibrations in the large bore piping. The developed forcing function permits design evaluation of the piping system, which leads to remedial actions and enables fatigue life determination, thus providing confidence to system operation. The forcing function approach is shown to be useful in finding potential vibration area and verifying the integrity of weak structure links. Application is to steam lines at BWR plants.

  2. Heat pipes in space and on earth

    NASA Technical Reports Server (NTRS)

    Ollendorf, S.

    1978-01-01

    The heat pipe is a closed tube whose inner surfaces are lined with a porous capillary wick. The wick is saturated with the liquid phase of a working fluid. The heat supplied at one end of the tube, the evaporator, causes evaporation of the working fluid. The vapor will pass to the other end of the tube, the condenser, where it will condense and release the latent heat of vaporization to a heat sink in that section of the pipe. Problems concerning a design of heat pipes for space applications are related to certain difficulties regarding the prediction of device performance under zero-g conditions. Heat pipes are usually tested on the ground under the influence of gravity, and then their performance is extrapolated to space. A description is presented of the approaches used to insure good heat pipe performance in space. Attention is given to an international heat pipe experiment conducted to accumulate zero-g performance data for several new and unique heat pipe designs, heat pipes for ATS-6, cryogenic heat pipes, and future activities.

  3. Pipe crawlers: Versatile adaptations for real applications

    SciTech Connect

    Hapstack, M.; Talarek, T.R.

    1990-01-01

    A problem at the Savannah River Site requires the unique application of a pipe crawler. A number of stainless steel pipes buried in concrete require ultrasonic inspection of the heat affected zones of the welds for detection of flaws or cracks. The paper describes the utilization of an inch-worm motion pipe crawler which negotiates a 90 degree reducing elbow with significant changes in diameter and vertical sections before entering the area of concern. After a discussion of general considerations and problem description, special requirements to meet the objectives and the design approach regarding the tractor, control system, instrument carriage, and radiation protection are discussed. 2 refs., 11 figs. (MB)

  4. New NAS Parallel Benchmarks Results

    NASA Technical Reports Server (NTRS)

    Yarrow, Maurice; Saphir, William; VanderWijngaart, Rob; Woo, Alex; Kutler, Paul (Technical Monitor)

    1997-01-01

    NPB2 (NAS (NASA Advanced Supercomputing) Parallel Benchmarks 2) is an implementation, based on Fortran and the MPI (message passing interface) message passing standard, of the original NAS Parallel Benchmark specifications. NPB2 programs are run with little or no tuning, in contrast to NPB vendor implementations, which are highly optimized for specific architectures. NPB2 results complement, rather than replace, NPB results. Because they have not been optimized by vendors, NPB2 implementations approximate the performance a typical user can expect for a portable parallel program on distributed memory parallel computers. Together these results provide an insightful comparison of the real-world performance of high-performance computers. New NPB2 features: New implementation (CG), new workstation class problem sizes, new serial sample versions, more performance statistics.

  5. Flexible ocean upwelling pipe

    DOEpatents

    Person, Abraham (Los Alamitos, CA)

    1980-01-01

    In an ocean thermal energy conversion facility, a cold water riser pipe is releasably supported at its upper end by the hull of the floating facility. The pipe is substantially vertical and has its lower end far below the hull above the ocean floor. The pipe is defined essentially entirely of a material which has a modulus of elasticity substantially less than that of steel, e.g., high density polyethylene, so that the pipe is flexible and compliant to rather than resistant to applied bending moments. The position of the lower end of the pipe relative to the hull is stabilized by a weight suspended below the lower end of the pipe on a flexible line. The pipe, apart from the weight, is positively buoyant. If support of the upper end of the pipe is released, the pipe sinks to the ocean floor, but is not damaged as the length of the line between the pipe and the weight is sufficient to allow the buoyant pipe to come to a stop within the line length after the weight contacts the ocean floor, and thereafter to float submerged above the ocean floor while moored to the ocean floor by the weight. The upper end of the pipe, while supported by the hull, communicates to a sump in the hull in which the water level is maintained below the ambient water level. The sump volume is sufficient to keep the pipe full during heaving of the hull, thereby preventing collapse of the pipe.

  6. Thermal Performance Benchmarking (Presentation)

    SciTech Connect

    Moreno, G.

    2014-11-01

    This project will benchmark the thermal characteristics of automotive power electronics and electric motor thermal management systems. Recent vehicle systems will be benchmarked to establish baseline metrics, evaluate advantages and disadvantages of different thermal management systems, and identify areas of improvement to advance the state-of-the-art.

  7. USGS Yosemite Benchmark Streamgage

    USGS Multimedia Gallery

    In this image, the USGS Hydrologic Benchmark Streamgage on the Merced River in Yosemite Valley can be seen. Hydrologic Benchmark streamgages are those at which no human development exists upstream of the streamgage. This streamgage is a cooperation between the National Park Service, National Oceanic...

  8. BENCHMARK DOSE SOFTWARE (BMDS)

    EPA Science Inventory

    EPA has announced the latest update to the Benchmark Dose Software (BMDS) tool which is used to facilitate the application of benchmark dose (BMD) methods to EPA hazardous pollutant risk assessments. This latest version (1.4.1b) contains seventeen (17) different models that ar...

  9. Numerical methods: Analytical benchmarking in transport theory

    SciTech Connect

    Ganapol, B.D. )

    1988-01-01

    Numerical methods applied to reactor technology have reached a high degree of maturity. Certainly one- and two-dimensional neutron transport calculations have become routine, with several programs available on personal computer and the most widely used programs adapted to workstation and minicomputer computational environments. With the introduction of massive parallelism and as experience with multitasking increases, even more improvement in the development of transport algorithms can be expected. Benchmarking an algorithm is usually not a very pleasant experience for the code developer. Proper algorithmic verification by benchmarking involves the following considerations: (1) conservation of particles, (2) confirmation of intuitive physical behavior, and (3) reproduction of analytical benchmark results. By using today's computational advantages, new basic numerical methods have been developed that allow a wider class of benchmark problems to be considered.

  10. Verification and validation benchmarks.

    SciTech Connect

    Oberkampf, William Louis; Trucano, Timothy Guy

    2007-02-01

    Verification and validation (V&V) are the primary means to assess the accuracy and reliability of computational simulations. V&V methods and procedures have fundamentally improved the credibility of simulations in several high-consequence fields, such as nuclear reactor safety, underground nuclear waste storage, and nuclear weapon safety. Although the terminology is not uniform across engineering disciplines, code verification deals with assessing the reliability of the software coding, and solution verification deals with assessing the numerical accuracy of the solution to a computational model. Validation addresses the physics modeling accuracy of a computational simulation by comparing the computational results with experimental data. Code verification benchmarks and validation benchmarks have been constructed for a number of years in every field of computational simulation. However, no comprehensive guidelines have been proposed for the construction and use of V&V benchmarks. For example, the field of nuclear reactor safety has not focused on code verification benchmarks, but it has placed great emphasis on developing validation benchmarks. Many of these validation benchmarks are closely related to the operations of actual reactors at near-safety-critical conditions, as opposed to being more fundamental-physics benchmarks. This paper presents recommendations for the effective design and use of code verification benchmarks based on manufactured solutions, classical analytical solutions, and highly accurate numerical solutions. In addition, this paper presents recommendations for the design and use of validation benchmarks, highlighting the careful design of building-block experiments, the estimation of experimental measurement uncertainty for both inputs and outputs to the code, validation metrics, and the role of model calibration in validation. It is argued that the understanding of predictive capability of a computational model is built on the level of achievement in V&V activities, how closely related the V&V benchmarks are to the actual application of interest, and the quantification of uncertainties related to the application of interest.

  11. Monitoring pipes for residual alpha contamination

    SciTech Connect

    MacArthur, D.; Rawool-Sullivan, M.; Dockray, T.

    1996-12-31

    The sensitivity and application of traditional alpha monitors is limited by the short range of alpha particles in air (typically 10 cm) and in solid materials (typically tens of {mu}m). Detecting small amounts of alpha-emitting contamination inside pipes presents particular problems. The alpha particle cannot penetrate the walls of the pipe. Associated gamma-ray detection and active neutron interrogation is often used to detect large amounts of radioactive material in pipes, but these methods are of limited use for detecting small amounts of contamination. Insertion of traditional alpha probes works well in large-diameter straight, pipes, but is increasingly difficult as the pipe network becomes smaller in diameter and more complex. Monitors based on long-range alpha detection (LRAD) detect ionization of the ambient air rather than the alpha particles themselves. A small fan draws the ions into an externally mounted ion detector. Thus, the air in the pipe serves as both the detector gas and the mechanism for transporting the alpha-induced ions to a detection grid outside of the pipe. All of the ions created by all of the contamination in the pipe can be measured in a single detector. Since ambient air serves as the {open_quotes}probe,{close_quotes} crushed or twisted sections of pipe can be monitored almost as effectively as straight sections. The pipe monitoring system described in this paper was tested both at Los Alamos and at BNFL`s Sellafield reprocessing facility in the UK. In this paper, the authors report on the first field tests of the pipe monitoring system.

  12. Benchmarking massively parallel architectures

    SciTech Connect

    Lubeck, O.; Moore, J.; Simmons, M.; Wasserman, H.

    1993-07-01

    The purpose of this paper is to summarize some initial experiences related to measuring the performance of massively parallel processors (MPPs) at Los Alamos National Laboratory (LANL). Actually, the range of MPP architectures the authors have used is rather limited, being confined mostly to the Thinking Machines Corporation (TMC) Connection Machine CM-2 and CM-5. Some very preliminary work has been carried out on the Kendall Square KSR-1, and efforts related to other machines, such as the Intel Paragon and the soon-to-be-released CRAY T3D are planned. This paper will concentrate more on methodology rather than discuss specific architectural strengths and weaknesses; the latter is expected to be the subject of future reports. MPP benchmarking is a field in critical need of structure and definition. As the authors have stated previously, such machines have enormous potential, and there is certainly a dire need for orders of magnitude computational power over current supercomputers. However, performance reports for MPPs must emphasize actual sustainable performance from real applications in a careful, responsible manner. Such has not always been the case. A recent paper has described in some detail, the problem of potentially misleading performance reporting in the parallel scientific computing field. Thus, in this paper, the authors briefly offer a few general ideas on MPP performance analysis.

  13. Toxicological Benchmarks for Wildlife

    SciTech Connect

    Sample, B.E. Opresko, D.M. Suter, G.W.

    1993-01-01

    Ecological risks of environmental contaminants are evaluated by using a two-tiered process. In the first tier, a screening assessment is performed where concentrations of contaminants in the environment are compared to no observed adverse effects level (NOAEL)-based toxicological benchmarks. These benchmarks represent concentrations of chemicals (i.e., concentrations presumed to be nonhazardous to the biota) in environmental media (water, sediment, soil, food, etc.). While exceedance of these benchmarks does not indicate any particular level or type of risk, concentrations below the benchmarks should not result in significant effects. In practice, when contaminant concentrations in food or water resources are less than these toxicological benchmarks, the contaminants may be excluded from further consideration. However, if the concentration of a contaminant exceeds a benchmark, that contaminant should be retained as a contaminant of potential concern (COPC) and investigated further. The second tier in ecological risk assessment, the baseline ecological risk assessment, may use toxicological benchmarks as part of a weight-of-evidence approach (Suter 1993). Under this approach, based toxicological benchmarks are one of several lines of evidence used to support or refute the presence of ecological effects. Other sources of evidence include media toxicity tests, surveys of biota (abundance and diversity), measures of contaminant body burdens, and biomarkers. This report presents NOAEL- and lowest observed adverse effects level (LOAEL)-based toxicological benchmarks for assessment of effects of 85 chemicals on 9 representative mammalian wildlife species (short-tailed shrew, little brown bat, meadow vole, white-footed mouse, cottontail rabbit, mink, red fox, and whitetail deer) or 11 avian wildlife species (American robin, rough-winged swallow, American woodcock, wild turkey, belted kingfisher, great blue heron, barred owl, barn owl, Cooper's hawk, and red-tailed hawk, osprey) (scientific names for both the mammalian and avian species are presented in Appendix B). [In this document, NOAEL refers to both dose (mg contaminant per kg animal body weight per day) and concentration (mg contaminant per kg of food or L of drinking water)]. The 20 wildlife species were chosen because they are widely distributed and provide a representative range of body sizes and diets. The chemicals are some of those that occur at U.S. Department of Energy (DOE) waste sites. The NOAEL-based benchmarks presented in this report represent values believed to be nonhazardous for the listed wildlife species; LOAEL-based benchmarks represent threshold levels at which adverse effects are likely to become evident. These benchmarks consider contaminant exposure through oral ingestion of contaminated media only. Exposure through inhalation and/or direct dermal exposure are not considered in this report.

  14. Pipe-to-pipe impact program

    SciTech Connect

    Alzheimer, J.M.; Bampton, M.C.C.; Friley, J.R.; Simonen, F.A.

    1984-06-01

    This report documents the tests and analyses performed as part of the Pipe-to-Pipe Impact (PTPI) Program at the Pacific Northwest Laboratory. This work was performed to assist the NRC in making licensing decisions regarding pipe-to-pipe impact events following postulated breaks in high energy fluid system piping. The report scope encompasses work conducted from the program's start through the completion of the initial hot oil tests. The test equipment, procedures, and results are described, as are analytic studies of failure potential and data correlation. Because the PTPI Program is only partially completed, the total significance of the current test results cannot yet be accurately assessed. Therefore, although trends in the data are discussed, final conclusions and recommendations will be possible only after the completion of the program, which is scheduled to end in FY 1984.

  15. Benchmark Solutions for Computational Aeroacoustics (CAA) Code Validation

    NASA Technical Reports Server (NTRS)

    Scott, James R.

    2004-01-01

    NASA has conducted a series of Computational Aeroacoustics (CAA) Workshops on Benchmark Problems to develop a set of realistic CAA problems that can be used for code validation. In the Third (1999) and Fourth (2003) Workshops, the single airfoil gust response problem, with real geometry effects, was included as one of the benchmark problems. Respondents were asked to calculate the airfoil RMS pressure and far-field acoustic intensity for different airfoil geometries and a wide range of gust frequencies. This paper presents the validated that have been obtained to the benchmark problem, and in addition, compares them with classical flat plate results. It is seen that airfoil geometry has a strong effect on the airfoil unsteady pressure, and a significant effect on the far-field acoustic intensity. Those parts of the benchmark problem that have not yet been adequately solved are identified and presented as a challenge to the CAA research community.

  16. Heat pipes. [technology utilization

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The development and use of heat pipes are described, including space requirements and contributions. Controllable heat pipes, and designs for automatically maintaining a selected constant temperature, are discussed which would add to the versatility and usefulness of heat pipes in industrial processing, manufacture of integrated circuits, and in temperature stabilization of electronics.

  17. TWODANT benchmark. Progress report

    SciTech Connect

    Lee, Sung

    1994-01-11

    TWODANT (Two-Dimensional, Diffusion-Accelerated, Neutral-Particle Transport) code has been benchmarked against 6 critical experiments (Jezebel plutonium critical assembly) and their k effective values compared with those of KENO and MCNP codes.

  18. BENCHMARKING SUSTAINABILITY ENGINEERING EDUCATION

    EPA Science Inventory

    The goals of this project are to develop and apply a methodology for benchmarking curricula in sustainability engineering and to identify individuals active in sustainability engineering education.

  19. Reciprocating excitation of a flexible beam: Benchmark study R.G. Langlois, M.J.D. Hayes *

    E-print Network

    Hayes, John

    --bothfor systemshaving open-and closed-loop topology. Correspondingly, benchmark problems have been developed where results. Arguably, the two most common benchmark problems are the flexible beam spin-up prob- lem for open, for example, Meijaard [2]). Many other benchmark problems have also been used. However, it is widely

  20. Published in Computers and Fluids Vol. 35, pp. 372-392, 2006 Solutions of 3D Navier-Stokes benchmark

    E-print Network

    Richter, Thomas

    -Stokes benchmark problems with adaptive finite elements M. Braack T. Richter This paper presents a numerical study of 3D Navier-Stokes benchmark problems de- fined within the DFG high-priority research program in 1996 of benchmark problems has been defined by Sch¨afer & Turek [2]. The task was to calculate different

  1. Benchmarks for Global Optimization and Continuous Constraint Satisfaction

    E-print Network

    Neumaier, Arnold

    .L.Toint, also part of Vanderbei's AMPL test collection [11]. 1 #12; The benchmark collected for the COCONUT at http://www.mat.univie.ac.at/~neum/glopt/coconut/benchmark.html The problems range in diculty from easy

  2. The ILTP Library: Benchmarking Automated Theorem Provers for Intuitionistic Logic

    E-print Network

    Otten, Jens

    The ILTP Library: Benchmarking Automated Theorem Provers for Intuitionistic Logic,jeotten,kreitz}@cs.uni-potsdam.de Abstract. The Intuitionistic Logic Theorem Proving (ILTP) Library provides a platfom for testing Introduction Benchmarking automated theorem proving (ATP) systems using standardised problem sets is a well

  3. WHY BENCHMARKING IS AN (ASYMPTOTICALLY) OPTIMAL

    E-print Network

    Kreinovich, Vladik

    PROOF Vladik Kreinovich and Scott A. Starks NASA Pan-American Center for Earth and Environmental Studies several methods) that solves all these bench- mark problems, and start using this method to solve other for a method that works well not only for the old bench- marks, but for the new benchmark as well. After

  4. WHY BENCHMARKING IS AN (ASYMPTOTICALLY) OPTIMAL

    E-print Network

    Kreinovich, Vladik

    PROOF Vladik Kreinovich and Scott A. Starks NASA PanAmerican Center for Earth and Environmental Studies several methods) that solves all these bench mark problems, and start using this method to solve other for a method that works well not only for the old bench marks, but for the new benchmark as well. After

  5. Storage-Intensive Supercomputing Benchmark Study

    SciTech Connect

    Cohen, J; Dossa, D; Gokhale, M; Hysom, D; May, J; Pearce, R; Yoo, A

    2007-10-30

    Critical data science applications requiring frequent access to storage perform poorly on today's computing architectures. This project addresses efficient computation of data-intensive problems in national security and basic science by exploring, advancing, and applying a new form of computing called storage-intensive supercomputing (SISC). Our goal is to enable applications that simply cannot run on current systems, and, for a broad range of data-intensive problems, to deliver an order of magnitude improvement in price/performance over today's data-intensive architectures. This technical report documents much of the work done under LDRD 07-ERD-063 Storage Intensive Supercomputing during the period 05/07-09/07. The following chapters describe: (1) a new file I/O monitoring tool iotrace developed to capture the dynamic I/O profiles of Linux processes; (2) an out-of-core graph benchmark for level-set expansion of scale-free graphs; (3) an entity extraction benchmark consisting of a pipeline of eight components; and (4) an image resampling benchmark drawn from the SWarp program in the LSST data processing pipeline. The performance of the graph and entity extraction benchmarks was measured in three different scenarios: data sets residing on the NFS file server and accessed over the network; data sets stored on local disk; and data sets stored on the Fusion I/O parallel NAND Flash array. The image resampling benchmark compared performance of software-only to GPU-accelerated. In addition to the work reported here, an additional text processing application was developed that used an FPGA to accelerate n-gram profiling for language classification. The n-gram application will be presented at SC07 at the High Performance Reconfigurable Computing Technologies and Applications Workshop. The graph and entity extraction benchmarks were run on a Supermicro server housing the NAND Flash 40GB parallel disk array, the Fusion-io. The Fusion system specs are as follows: SuperMicro X7DBE Xeon Dual Socket Blackford Server Motherboard; 2 Intel Xeon Dual-Core 2.66 GHz processors; 1 GB DDR2 PC2-5300 RAM (2 x 512); 80GB Hard Drive (Seagate SATA II Barracuda). The Fusion board is presently capable of 4X in a PCIe slot. The image resampling benchmark was run on a dual Xeon workstation with NVIDIA graphics card (see Chapter 5 for full specification). An XtremeData Opteron+FPGA was used for the language classification application. We observed that these benchmarks are not uniformly I/O intensive. The only benchmark that showed greater that 50% of the time in I/O was the graph algorithm when it accessed data files over NFS. When local disk was used, the graph benchmark spent at most 40% of its time in I/O. The other benchmarks were CPU dominated. The image resampling benchmark and language classification showed order of magnitude speedup over software by using co-processor technology to offload the CPU-intensive kernels. Our experiments to date suggest that emerging hardware technologies offer significant benefit to boosting the performance of data-intensive algorithms. Using GPU and FPGA co-processors, we were able to improve performance by more than an order of magnitude on the benchmark algorithms, eliminating the processor bottleneck of CPU-bound tasks. Experiments with a prototype solid state nonvolative memory available today show 10X better throughput on random reads than disk, with a 2X speedup on a graph processing benchmark when compared to the use of local SATA disk.

  6. KENTUCKY STRAIGHT PIPES REPORT, DECEMBER 2002

    EPA Science Inventory

    The poor sanitary conditions and water pollution problems EPA observed in the Kentucky counties of Harlan, Martin, Bath, and Montgomery were of the highest concern. The widespread scale of both the straight pipe issues as well as package plant wastewater problems present an envir...

  7. Shielding Benchmark Computational Analysis

    SciTech Connect

    Hunter, H.T.; Slater, C.O.; Holland, L.B.; Tracz, G.; Marshall, W.J.; Parsons, J.L.

    2000-09-17

    Over the past several decades, nuclear science has relied on experimental research to verify and validate information about shielding nuclear radiation for a variety of applications. These benchmarks are compared with results from computer code models and are useful for the development of more accurate cross-section libraries, computer code development of radiation transport modeling, and building accurate tests for miniature shielding mockups of new nuclear facilities. When documenting measurements, one must describe many parts of the experimental results to allow a complete computational analysis. Both old and new benchmark experiments, by any definition, must provide a sound basis for modeling more complex geometries required for quality assurance and cost savings in nuclear project development. Benchmarks may involve one or many materials and thicknesses, types of sources, and measurement techniques. In this paper the benchmark experiments of varying complexity are chosen to study the transport properties of some popular materials and thicknesses. These were analyzed using three-dimensional (3-D) models and continuous energy libraries of MCNP4B2, a Monte Carlo code developed at Los Alamos National Laboratory, New Mexico. A shielding benchmark library provided the experimental data and allowed a wide range of choices for source, geometry, and measurement data. The experimental data had often been used in previous analyses by reputable groups such as the Cross Section Evaluation Working Group (CSEWG) and the Organization for Economic Cooperation and Development/Nuclear Energy Agency Nuclear Science Committee (OECD/NEANSC).

  8. PNNL Information Technology Benchmarking

    SciTech Connect

    DD Hostetler

    1999-09-08

    Benchmarking is a methodology for searching out industry best practices that lead to superior performance. It is exchanging information, not just with any organization, but with organizations known to be the best within PNNL, in industry, or in dissimilar industries with equivalent functions. It is used as a continuous improvement tool for business and technical processes, products, and services. Information technology--comprising all computer and electronic communication products and services--underpins the development and/or delivery of many PNNL products and services. This document describes the Pacific Northwest National Laboratory's (PNNL's) approach to information technology (IT) benchmarking. The purpose is to engage other organizations in the collaborative process of benchmarking in order to improve the value of IT services provided to customers. TM document's intended audience consists of other US Department of Energy (DOE) national laboratories and their IT staff. Although the individual participants must define the scope of collaborative benchmarking, an outline of IT service areas for possible benchmarking is described.

  9. Water and Mercury Pipe Flow Simulation in FLUENTSimulation in FLUENT

    E-print Network

    McDonald, Kirk

    Water and Mercury Pipe Flow Simulation in FLUENTSimulation in FLUENT Yan Zhan, Foluso Ladeinde;Straight Pipe flow Ph i l bl-- Physical problem Isothermal mercury/ water flow through a 60D straight pipe* Mercury 1500 41.844 m 4.04 m/s 18.5 bar 15.67 bar Water 1500 331.404 m 4.04 m/s 18.5 bar 18.291bar *uave

  10. Deployable Heat Pipe Radiator

    NASA Technical Reports Server (NTRS)

    Edelstein, F.

    1975-01-01

    A 1.2- by 1.8-m variable conductance heat pipe radiator was designed, built, and tested. The radiator has deployment capability and can passively control Freon-21 fluid loop temperatures under varying loads and environments. It consists of six grooved variable conductance heat pipes attached to a 0.032-in. aluminum panel. Heat is supplied to the radiator via a fluid header or a single-fluid flexible heat pipe header. The heat pipe header is an artery design that has a flexible section capable of bending up to 90 degrees. Radiator loads as high as 850 watts were successfully tested. Over a load variation of 200 watts, the outlet temperature of the Freon-21 fluid varied by 7 F. An alternate control system was also investigated which used a variable conductance heat pipe header attached to the heat pipe radiator panel.

  11. Benchmarking Corporate Energy Management

    E-print Network

    Norland, D. L.

    2001-01-01

    stream_source_info ESL-IE-01-05-06.pdf.txt stream_content_type text/plain stream_size 7488 Content-Encoding ISO-8859-1 stream_name ESL-IE-01-05-06.pdf.txt Content-Type text/plain; charset=ISO-8859-1 BENCHMARKING... procedures and perfonnance compare to that of other companies. Energy management involves everything from setting goals and targets to implementing best maintenance practices. This paper, however, discusses benchmarking energy management practices...

  12. Abrasion resistant heat pipe

    DOEpatents

    Ernst, Donald M. (Leola, PA)

    1984-10-23

    A specially constructed heat pipe for use in fluidized bed combustors. Two distinct coatings are spray coated onto a heat pipe casing constructed of low thermal expansion metal, each coating serving a different purpose. The first coating forms aluminum oxide to prevent hydrogen permeation into the heat pipe casing, and the second coating contains stabilized zirconium oxide to provide abrasion resistance while not substantially affecting the heat transfer characteristics of the system.

  13. Abrasion resistant heat pipe

    DOEpatents

    Ernst, D.M.

    1984-10-23

    A specially constructed heat pipe is described for use in fluidized bed combustors. Two distinct coatings are spray coated onto a heat pipe casing constructed of low thermal expansion metal, each coating serving a different purpose. The first coating forms aluminum oxide to prevent hydrogen permeation into the heat pipe casing, and the second coating contains stabilized zirconium oxide to provide abrasion resistance while not substantially affecting the heat transfer characteristics of the system.

  14. Internal pipe attachment mechanism

    DOEpatents

    Bast, R.M.; Chesnut, D.A.; Henning, C.D.; Lennon, J.P.; Pastrnak, J.W.; Smith, J.A.

    1994-12-13

    An attachment mechanism is described for repairing or extending fluid carrying pipes, casings, conduits, etc. utilizing one-way motion of spring tempered fingers to provide a mechanical connection between the attachment mechanism and the pipe. The spring tempered fingers flex to permit insertion into a pipe to a desired insertion depth. The mechanical connection is accomplished by reversing the insertion motion and the mechanical leverage in the fingers forces them outwardly against the inner wall of the pipe. A seal is generated by crushing a sealing assembly by the action of setting the mechanical connection. 6 figures.

  15. External artery heat pipe

    NASA Technical Reports Server (NTRS)

    Gernert, Nelson J. (Inventor); Ernst, Donald M. (Inventor); Shaubach, Robert M. (Inventor)

    1989-01-01

    An improved heat pipe with an external artery. The longitudinal slot in the heat pipe wall which interconnects the heat pipe vapor space with the external artery is completely filled with sintered wick material and the wall of the external artery is also covered with sintered wick material. This added wick structure assures that the external artery will continue to feed liquid to the heat pipe evaporator even if a vapor bubble forms within and would otherwise block the liquid transport function of the external artery.

  16. Heat Pipe Materials Compatibility

    NASA Technical Reports Server (NTRS)

    Eninger, J. E.; Fleischman, G. L.; Luedke, E. E.

    1976-01-01

    An experimental program to evaluate noncondensable gas generation in ammonia heat pipes was completed. A total of 37 heat pipes made of aluminum, stainless steel and combinations of these materials were processed by various techniques, operated at different temperatures and tested at low temperature to quantitatively determine gas generation rates. In order of increasing stability are aluminum/stainless combination, all aluminum and all stainless heat pipes. One interesting result is the identification of intentionally introduced water in the ammonia during a reflux step as a means of surface passivation to reduce gas generation in stainless-steel/aluminum heat pipes.

  17. Pipe crawler apparatus

    DOEpatents

    Hovis, Gregory L. (North Augusta, SC); Erickson, Scott A. (Augusta, GA); Blackmon, Bruce L. (Aiken, SC)

    2002-01-01

    A pipe crawler apparatus particularly useful for 3-inch and 4-inch diameter pipes is provided. The pipe crawler apparatus uses a gripping apparatus in which a free end of a piston rod is modified with a bearing retaining groove. Bearings, placed within the groove, are directed against a camming surface of three respective pivoting support members. The non-pivoting ends of the support members carry a foot-like gripping member that, upon pivoting of the support member, engages the interior wall of the pipe.

  18. Heat Pipe Planets

    NASA Technical Reports Server (NTRS)

    Moore, William B.; Simon, Justin I.; Webb, A. Alexander G.

    2014-01-01

    When volcanism dominates heat transport, a terrestrial body enters a heat-pipe mode, in which hot magma moves through the lithosphere in narrow channels. Even at high heat flow, a heat-pipe planet develops a thick, cold, downwards-advecting lithosphere dominated by (ultra-)mafic flows and contractional deformation at the surface. Heat-pipes are an important feature of terrestrial planets at high heat flow, as illustrated by Io. Evidence for their operation early in Earth's history suggests that all terrestrial bodies should experience an episode of heat-pipe cooling early in their histories.

  19. Introduction to Heat Pipes

    NASA Technical Reports Server (NTRS)

    Ku, Jentung

    2015-01-01

    This is the presentation file for the short course Introduction to Heat Pipes, to be conducted at the 2015 Thermal Fluids and Analysis Workshop, August 3-7, 2015, Silver Spring, Maryland. NCTS 21070-15. Course Description: This course will present operating principles of the heat pipe with emphases on the underlying physical processes and requirements of pressure and energy balance. Performance characterizations and design considerations of the heat pipe will be highlighted. Guidelines for thermal engineers in the selection of heat pipes as part of the spacecraft thermal control system, testing methodology, and analytical modeling will also be discussed.

  20. Monte Carlo Benchmark

    Energy Science and Technology Software Center (ESTSC)

    2010-10-20

    The "Monte Carlo Benchmark" (MCB) is intended to model the computatiional performance of Monte Carlo algorithms on parallel architectures. It models the solution of a simple heuristic transport equation using a Monte Carlo technique. The MCB employs typical features of Monte Carlo algorithms such as particle creation, particle tracking, tallying particle information, and particle destruction. Particles are also traded among processors using MPI calls.

  1. Benchmarks: WICHE Region 2012

    ERIC Educational Resources Information Center

    Western Interstate Commission for Higher Education, 2013

    2013-01-01

    Benchmarks: WICHE Region 2012 presents information on the West's progress in improving access to, success in, and financing of higher education. The information is updated annually to monitor change over time and encourage its use as a tool for informed discussion in policy and education communities. To establish a general context for the

  2. Bryce Canyon Benchmark

    USGS Multimedia Gallery

    A USGS elevation benchmark in Bryce Canyon National Park. Bryce Canyon is a unique sandstone formation in southern Utah. It is home to a large number of hoodoos, which are oddly shaped pillars of rock that formed due to different erosion rates for the dolomite that caps them and the sandstone that ...

  3. Comparison of five benchmarks

    SciTech Connect

    Huss, J. E.; Pennline, J. A.

    1987-02-01

    Five benchmark programs were obtained and run on the NASA Lewis CRAY X-MP/24. A comparison was made between the programs codes and between the methods for calculating performance figures. Several multitasking jobs were run to gain experience in how parallel performance is measured.

  4. Benchmarking the World's Best

    ERIC Educational Resources Information Center

    Tucker, Marc S.

    2012-01-01

    A century ago, the United States was a world leader in industrial benchmarking. However, after World War II, once no one could compete with the U.S., it became complacent. Many industrialized countries now have higher student achievement and more equitable and efficient education systems. A higher proportion of young people in their workforces

  5. NAS Parallel Benchmarks Results 3-95

    NASA Technical Reports Server (NTRS)

    Saini, Subhash; Bailey, David H.; Walter, Howard (Technical Monitor)

    1995-01-01

    The NAS Parallel Benchmarks (NPB) were developed in 1991 at NASA Ames Research Center to study the performance of parallel supercomputers. The eight benchmark problems are specified in a "pencil and paper" fashion, i.e., the complete details of the problem are given in a NAS technical document. Except for a few restrictions, benchmark implementors are free to select the language constructs and implementation techniques best suited for a particular system. In this paper, we present new NPB performance results for the following systems: (a) Parallel-Vector Processors: CRAY C90, CRAY T90 and Fujitsu VPP500; (b) Highly Parallel Processors: CRAY T3D, IBM SP2-WN (Wide Nodes), and IBM SP2-TN2 (Thin Nodes 2); and (c) Symmetric Multiprocessors: Convex Exemplar SPPIOOO, CRAY J90, DEC Alpha Server 8400 5/300, and SGI Power Challenge XL (75 MHz). We also present sustained performance per dollar for Class B LU, SP and BT benchmarks. We also mention future NAS plans for the NPB.

  6. Application of remote-control in-pipe inspection technology

    SciTech Connect

    Watanabe, H.; Ozawa, K.

    1988-01-01

    At nuclear power plants, there is a strong desire to maintain plant components soundly and to enhance the operation rate. Such a desire has increased the importance of the internal inspection of piping that accounts for a large percentage of plant components. To meet these needs, JGC Corporation in Japan has developed and practically applied various types of in-pipe traveling inspection robots applicable to piping that ranges in size from 4 to 24 in. in diameter. This paper introduces two robots that were developed recently: robot for 4- to 6-in. piping and a robot for 8- to 24-in. piping. Conventional in-pipe traveling inspection robots for small-diameter piping (6 in. and smaller) had difficulty passing inside 90-deg short elbows. The adoption of a spiral drive and special gears, however, has enabled passing inside of such elbows. Of conventional inspection robots for large-diameter piping, most of those which used a crawler drive to increase traction were apt to lose a certain amount of tractive force when they passed inside 90-deg short elbows. In the robot introduced herein, however, this problem was solved by developing a special crawler, which allowed slippage in the circumferential direction of the piping. At present, robots for small-diameter piping have been permanently installed and practically applied to the inspection of concentrator lines of radwaste facilities.

  7. These Pipes Are "Happening"

    ERIC Educational Resources Information Center

    Skophammer, Karen

    2010-01-01

    The author is blessed with having the water pipes for the school system in her office. In this article, the author describes how the breaking of the pipes had led to a very worthwhile art experience for her students. They practiced contour and shaded drawing techniques, reviewed patterns and color theory, and used their reasoning skills--all while

  8. Quantum benchmarks for pure single-mode Gaussian states.

    PubMed

    Chiribella, Giulio; Adesso, Gerardo

    2014-01-10

    Teleportation and storage of continuous variable states of light and atoms are essential building blocks for the realization of large-scale quantum networks. Rigorous validation of these implementations require identifying, and surpassing, benchmarks set by the most effective strategies attainable without the use of quantum resources. Such benchmarks have been established for special families of input states, like coherent states and particular subclasses of squeezed states. Here we solve the longstanding problem of defining quantum benchmarks for general pure Gaussian single-mode states with arbitrary phase, displacement, and squeezing, randomly sampled according to a realistic prior distribution. As a special case, we show that the fidelity benchmark for teleporting squeezed states with totally random phase and squeezing degree is 1/2, equal to the corresponding one for coherent states. We discuss the use of entangled resources to beat the benchmarks in experiments. PMID:24483875

  9. Analysis of Rotary Bayonets and Piping

    SciTech Connect

    Chess, K.; Wendlandt, J.; /Fermilab

    1988-08-19

    This report quantifies certain characteristics of the rotary bayonets and associated platform piping on the DO detector. The Vacuum Jacketed 4-inch x 6-inch and 1.5-inch x 3-inch and the 4-inch and 6-inch vacuum pipe articulating jumpers are considered here. The values of greatest importance are the forces required at the bayonet moment arms given in Table II and the stresses summarized in Table III. The forces required should be noted and checked that they are acceptable to the problem. The maximum bending stresses of the vacuum pipes do not exceed 1000 psi and are essentially negligible. The 4-inch x 6-inch vacuum jacketed line experiences the maximum bending stress of 10,300 psi. According to code B31.1, the maximum allowable bending stress is 25,500 psi. The major sources of error in these calculations should be summarized. First, all weights used were approximations and all lengths used were scaled from drawings. Second, while the FRAME MAC{trademark} models resemble the vacuum pipe articulating jumpers, they are definitely simplified. For instance, they do not account for the different stiffnesses of the unions. Finally, the bayonets in the ANSYS models consist of an outer jacket and an inner pipe fixed together at the end of the male sleeve. The actual bayonets are more complex and are composed of various sizes of tubes and pipes which affect the stiffness of the section.

  10. Extendable pipe crawler

    DOEpatents

    Hapstack, M.

    1991-05-28

    A pipe crawler is described having a front leg assembly and a back leg assembly connected together by two air cylinders, each leg assembly having four extendable legs and a pair of actuators for sliding the extendable legs radially outward to increase the range of the legs when the pipe crawler enters a section of a pipe having a larger diameter. The crawler crawls by inchworm'-like motion, the front leg assembly and back leg assembly alternately engaging and disengaging the wall of the pipe to hold the pipe crawler as the air cylinders alternately advance the front leg assembly and bring up the rear leg assembly. The pair of actuators of each leg assembly are parallel, adjacent and opposing acting so that each slides two adjacent extendable legs radially outward. 5 figures.

  11. Extendable pipe crawler

    DOEpatents

    Hapstack, Mark (North Augusta, SC)

    1991-01-01

    A pipe crawler having a front leg assembly and a back leg assembly connected together by two air cylinders, each leg assembly having four extendable legs and a pair of actuators for sliding the extendable legs radially outward to increase the range of the legs when the pipe crawler enters a section of a pipe having a larger diameter. The crawler crawls by "inchworm"-like motion, the front leg assembly and back leg assembly alternately engaging and disengaging the wall of the pipe to hold the pipe crawler as the air cylinders alternately advance the front leg assembly and bring up the rear leg assembly. The pair of actuators of each leg assembly are parallel, adjacent and opposing acting so that each slides two adjacent extendable legs radially outward.

  12. Benchmarking The Influence of Information-Processing Architectures on Intelligent

    E-print Network

    Wyatt, Jeremy

    on intelligent robots. We separate this problem into two sub-problems: benchmarking the architecture design-overlooked, element of the science of designing and building intelligent robots (and other systems). This paper to intelligent system design has a number of problems (some of which this work- shop is trying to address

  13. Roadmap to Realistic Modeling of Closed Loop Pulsating Heat Pipes Sameer Khandekar

    E-print Network

    Khandekar, Sameer

    Roadmap to Realistic Modeling of Closed Loop Pulsating Heat Pipes Sameer Khandekar and Manfred modeling of pulsating heat pipes through `first' principles is a contemporary problem which remains quite is presented which is based on the fact that at high enough heat flux level, Closed Loop Pulsating Heat Pipes

  14. International Heat Pipe Conference (13th IHPC), Shanghai, China, September 21-25, 2004.

    E-print Network

    Khandekar, Sameer

    13th International Heat Pipe Conference (13th IHPC), Shanghai, China, September 21-25, 2004. 7$&7 Mathematical modeling of pulsating heat pipes through `first' principles is a contemporary problem which flux level, closed loop pulsating heat pipes experience a bulk internal unidirectional fluid

  15. An optical method for measuring the thickness of a falling condensate in gravity assisted heat pipe

    NASA Astrophysics Data System (ADS)

    Kasanick, Martin; Lenhard, Richard; Kaduchov, Katarna; Malcho, Milan

    2015-05-01

    A large number of variables is the main problem of designing systems which uses heat pipes, whether it is a traditional - gravity, or advanced - capillary, pulsating, advanced heat pipes. This article is a methodology for measuring the thickness of the falling condensate in gravitational heat pipes, with using the optical triangulation method, and the evaluation of risks associated with this method.

  16. MPI Multicore Linktest Benchmark

    SciTech Connect

    2008-01-25

    The MPI Multicore Linktest (LinkTest) measures the aggregate bandwidth from/to a multicore node in a parallel system. It allows the user to specify a variety of different node layout and communication routine variations and reports the maximal observed bandwidth across all specified options. In particular, this benchmark is able to vary the number of tasks on the root node and thereby allows users to study the impact of multicore architectures on MPI communication performance.

  17. Using Flexible Pipe (poly-pipe) with Surface Irrigation

    E-print Network

    Peries, Xavier; Enciso, Juan

    2005-10-05

    ? Poly-pipe rolls ? Pump or valve for connection ? Clamps, rubber straps, or duct tape ? Shovel ? PVC connectors (if more than one roll is used) ? Hole puncher with plugs Prior to poly-pipe installation, fields should be leveled. Poly-pipe should.... Advantages of Using Pipes to Deliver Irrigation Water Using pipe systems (rather than earthen ditches) to convey and distribute water to fields has several advantages: ? Increases in on-farm irrigation efficiency, by avoiding water loss due to deep...

  18. NAS Parallel Benchmarks I/O Version 2.4. 2.4

    NASA Technical Reports Server (NTRS)

    Wong, Parkson; VanderWijngaart, Rob F.; Biegel, Bryan A. (Technical Monitor)

    2002-01-01

    We describe a benchmark problem, based on the Block-Tridiagonal (BT) problem of the NAS Parallel Benchmarks (NPB), which is used to test the output capabilities of high-performance computing systems, especially parallel systems. We also present a source code implementation of the benchmark, called NPBIO2.4-MPI, based on the MPI implementation of NPB, using a variety of ways to write the computed solutions to file.

  19. Piping stress handbook. Second edition

    SciTech Connect

    Helguero, V.

    1986-01-01

    This abridged volume contains the following: Coefficients of thermal expansion. Allowable stress range for ANSI/ASME Power Piping Code B31.1. Stress intensification and flexibility factors. Pressure and stress ratios. Design criteria for allowable loads, moment, and stresses. Properties of pipe. Weight and dimensions of pipe and components. Pipe support selection and design. Fundamentals of expansion joints. Index.

  20. Experimenting with a "Pipe" Whistle

    ERIC Educational Resources Information Center

    Stafford, Olga

    2012-01-01

    A simple pipe whistle can be made using pieces of PVC pipe. The whistle can be used to measure the resonant frequencies of open or closed pipes. A slightly modified version of the device can be used to also investigate the interesting dependence of the sound frequencies produced on the orifice-to-edge distance. The pipe whistle described here

  1. Flexible ultrasonic pipe inspection apparatus

    DOEpatents

    Jenkins, C.F.; Howard, B.D.

    1994-01-01

    Pipe crawlers, pipe inspection {open_quotes}rabbits{close_quotes} and similar vehicles are widely used for inspecting the interior surfaces of piping systems, storage tanks and process vessels for damaged or flawed structural features. This paper describes the design of a flexible, modular ultrasonic pipe inspection apparatus.

  2. Pipe Insulation Economies

    E-print Network

    Schilling, R. E.

    1986-01-01

    stream_source_info ESL-IE-86-06-97.pdf.txt stream_content_type text/plain stream_size 11050 Content-Encoding ISO-8859-1 stream_name ESL-IE-86-06-97.pdf.txt Content-Type text/plain; charset=ISO-8859-1 PIPE INSULATION... ECONOMIES Robert E. Schilling, P.E. Eaton Corporation Aurora, Ohio ABSTRACT Pipe Insulation Economies is a computer pro gram written in IBM basic to simplify the economic insulation thickness for an insulated pipe. Many artic1es have been wr i...

  3. An electrohydrodynamic heat pipe.

    NASA Technical Reports Server (NTRS)

    Jones, T. B.

    1972-01-01

    A heat pipe of new design, using an electrode structure to orient and guide the dielectric liquid phase flow, is proposed. Analysis indicates that the operation of the electrohydrodynamic heat pipe is in direct analogy to capillary devices, with the polarization force acting in place of capillarity. Advantages of these new heat pipes include greatly reduced liquid friction, electrohydrodynamically enhanced evaporation and condensation heat transfer, and a possible voltage-controlled on/off feature. Preliminary calculations indicate that relatively high performance devices are possible.

  4. Electrohydrodynamic heat pipes.

    NASA Technical Reports Server (NTRS)

    Jones, T. B.

    1973-01-01

    An electrohydrodynamic heat pipe of radical design is proposed which substitutes polarization electrohydrodynamic force effects for capillarity in collecting, guiding, and pumping a condensate liquid phase. The discussed device is restricted to the use of dielectric liquids as working fluids. Because of the relatively poor thermal transport properties of these liquids, capillary heat pipes using these liquids have not been high performance devices. The employment of the electrohydrodynamic concept should enhance this performance and help fill the performance gap that exists in the temperature range from 250 F to 750 F for 'conventional' capillary heat pipes.

  5. Gas pipe explorer robot

    NASA Technical Reports Server (NTRS)

    Wilcox, Brian (Inventor)

    2004-01-01

    A gas pipe explorer formed of a plurality of connecting elements, and an articulation element between the connected elements. The connected elements include drive capabilities, and the articulation element allows the connected elements to traverse gas pipes of arbitrary shapes and sizes. A sensor may sends the characteristics of the gas pipe, and the communication element may send back those sends characteristics. The communication can be wired, over a tether connecting the device to a remote end. Alternatively, the connection can be wireless, driven by either a generator or a battery.

  6. VVER-1000 weapons-grade MOX computational benchmark analysis

    SciTech Connect

    Kalugin, M.A.; Lazarenko, A.P.; Kalahnikov, A.G.; Gehin, J.C.

    2000-05-07

    Calculations of computational benchmark problems for the disposition of weapons-grade plutonium fuel in VVER-1000 reactors have been performed under the Joint US/Russian Fissile Material Disposition Program. The benchmarks cover pin cell, single fuel assembly, and multi-assembly structures with several different fuel types, moderator densities, and boron content for operational and off-normal conditions. Fuel depletion is performed to a burnup of 60 MWd/kgHM. The results of the analysis of the benchmarks with US and Russian code systems have been compared and indicated good agreement among the different methods and data.

  7. Large variable conductance heat pipe. Transverse header

    NASA Technical Reports Server (NTRS)

    Edelstein, F.

    1975-01-01

    The characteristics of gas-loaded, variable conductance heat pipes (VCHP) are discussed. The difficulties involved in developing a large VCHP header are analyzed. The construction of the large capacity VCHP is described. A research project to eliminate some of the problems involved in large capacity VCHP operation is explained.

  8. Effective pipe coating takes care

    SciTech Connect

    Polkinhorne, D.A.

    1980-01-01

    A discussion of the operations involved in the preparation of effective hot-enamel pipe coating covers the storage, drying, and cleaning of the pipe, including the segregation of pipe carried on the deck of ocean-going ships or barges so as to allow weathering to remove salt spray; application of primer coatings; melting and heating of enamel; application of the hot enamel coating; inspection; and storage of coated pipe, and concludes that the effectiveness of a hot-enamel pipe coating is a shared responsibility between the pipeline owner, pipe-coating materials manufacturer, and the pipe-coating contractor.

  9. Improved Thin, Flexible Heat Pipes

    NASA Technical Reports Server (NTRS)

    Rosenfeld, John H.; Gernert, Nelson J.; Sarraf, David B.; Wollen, Peter J.; Surina, Frank C.; Fale, John E.

    2004-01-01

    Flexible heat pipes of an improved type are fabricated as layers of different materials laminated together into vacuum- tight sheets or tapes. In comparison with prior flexible heat pipes, these flexible heat pipes are less susceptible to leakage. Other advantages of these flexible heat pipes, relative to prior flexible heat pipes, include high reliability and greater ease and lower cost of fabrication. Because these heat pipes are very thin, they are highly flexible. When coated on outside surfaces with adhesives, these flexible heat pipes can be applied, like common adhesive tapes, to the surfaces of heat sinks and objects to be cooled, even if those surfaces are curved.

  10. Robot design for leak detection in water-pipe systems

    E-print Network

    Choi, Changrak

    2012-01-01

    Leaks are major problem that occur in the water pipelines all around the world. Several reports indicate loss of around 20 to 30 percent of water in the distribution of water through water pipe systems. Such loss of water ...

  11. A benchmark for galactic cosmic ray transport codes

    NASA Technical Reports Server (NTRS)

    Wilson, John W.; Townsend, Lawrence W.

    1987-01-01

    A nontrivial analytic benchmark solution for galactic cosmic ray transport is presented for use in transport code validation. Computational accuracy for a previously-developed cosmic ray transport code is established to within one percent by comparison with this exact benchmark. Hence, solution accuracy for the transport problem is mainly limited by inaccuracies in the input spectra, input interaction databases, and the use of a straight ahead/velocity-conserving approximation.

  12. A benchmark for galactic cosmic-ray transport codes

    NASA Technical Reports Server (NTRS)

    Wilson, John W.; Townsend, Lawrence W.

    1988-01-01

    A nontrivial analytic benchmark solution for galactic cosmic ray transport is presented for use in transport code validation. Computational accuracy for a previously-developed cosmic ray transport code is established to within one percent by comparison with this exact benchmark. Hence, solution accuracy for the transport problem is mainly limited by inaccuracies in the input spectra, input interaction databases, and the use of a straight ahead/velocity-conserving approximation.

  13. Comparison of numerical oblique detonation solutions with an asymptotic benchmark

    NASA Technical Reports Server (NTRS)

    Grismer, Matthew J.; Powers, Joseph M.

    1992-01-01

    In order to have confidence in a numerical method, the verification of its reproduction of known benchmark analytic solutions for simple model problems is of great importance. Attention is presently given to a novel benchmarking procedure for numerical models of high speed, reactive 2D flows. The procedure is illustrated by comparing asymptotic and numerical solutions for oblique detonations in which an attached oblique shock is followed by an exothermic reaction with a thick reaction zone.

  14. Self-benchmarking Guide for Data Centers: Metrics, Benchmarks, Actions

    SciTech Connect

    Mathew, Paul; Ganguly, Srirupa; Greenberg, Steve; Sartor, Dale

    2009-07-13

    This guide describes energy efficiency metrics and benchmarks that can be used to track the performance of and identify potential opportunities to reduce energy use in data centers. This guide is primarily intended for personnel who have responsibility for managing energy use in existing data centers - including facilities managers, energy managers, and their engineering consultants. Additionally, data center designers may also use the metrics and benchmarks described in this guide for goal-setting in new construction or major renovation. This guide provides the following information: (1) A step-by-step outline of the benchmarking process. (2) A set of performance metrics for the whole building as well as individual systems. For each metric, the guide provides a definition, performance benchmarks, and potential actions that can be inferred from evaluating this metric. (3) A list and descriptions of the data required for computing the metrics. This guide is complemented by spreadsheet templates for data collection and for computing the benchmarking metrics. This guide builds on prior data center benchmarking studies supported by the California Energy Commission. Much of the benchmarking data are drawn from the LBNL data center benchmarking database that was developed from these studies. Additional benchmark data were obtained from engineering experts including facility designers and energy managers. This guide also builds on recent research supported by the U.S. Department of Energy's Save Energy Now program.

  15. The pipes of pan.

    PubMed

    Chalif, David J

    2004-12-01

    The pipes of pan is the crowning achievement of Pablo Picasso's neoclassical period of the 1920s. This monumental canvas depicts a mythological Mediterranean scene in which two sculpted classical giants stare out, seemingly across the centuries, toward a distant and lost Arcadia. Picasso was influenced by Greco-Roman art during his travels in Italy, and his neoclassical works typically portray massive, immobile, and pensive figures. Pan and his pipes are taken directly from Greek mythological lore by Picasso and placed directly into 20th century art. He frequently turned to various mythological figures throughout his metamorphosing periods. The Pipes of Pan was also influenced by the painter's infatuation with the beautiful American expatriate Sara Murphy, and the finished masterpiece represents a revision of a previously conceived neoclassical work. The Pipes of Pan now hangs in the Musee Picasso in Paris. PMID:15574231

  16. Heat pipe manufacturing study

    NASA Technical Reports Server (NTRS)

    Edelstein, F.

    1974-01-01

    Heat pipe manufacturing methods are examined with the goal of establishing cost effective procedures that will ultimately result in cheaper more reliable heat pipes. Those methods which are commonly used by all heat pipe manufacturers have been considered, including: (1) envelope and wick cleaning, (2) end closure and welding, (3) mechanical verification, (4) evacuation and charging, (5) working fluid purity, and (6) charge tube pinch off. The study is limited to moderate temperature aluminum and stainless steel heat pipes with ammonia, Freon-21 and methanol working fluids. Review and evaluation of available manufacturers techniques and procedures together with the results of specific manufacturing oriented tests have yielded a set of recommended cost-effective specifications which can be used by all manufacturers.

  17. Heat Pipe Systems

    NASA Technical Reports Server (NTRS)

    1993-01-01

    The heat pipe was developed to alternately cool and heat without using energy or any moving parts. It enables non-rotating spacecraft to maintain a constant temperature when the surface exposed to the Sun is excessively hot and the non Sun-facing side is very cold. Several organizations, such as Tropic-Kool Engineering Corporation, joined NASA in a subsequent program to refine and commercialize the technology. Heat pipes have been installed in fast food restaurants in areas where humid conditions cause materials to deteriorate quickly. Moisture removal was increased by 30 percent in a Clearwater, FL Burger King after heat pipes were installed. Relative humidity and power consumption were also reduced significantly. Similar results were recorded by Taco Bell, which now specifies heat pipe systems in new restaurants in the Southeast.

  18. Miniature pipe crawler tractor

    DOEpatents

    McKay, Mark D. (Idaho Falls, ID); Anderson, Matthew O. (Idaho Falls, ID); Ferrante, Todd A. (Westerville, OH); Willis, W. David (Idaho Falls, ID)

    2000-01-01

    A pipe crawler tractor may comprise a half tractor assembly having a first base drive wheel, a second base drive wheel, and a top drive wheel. The drive wheels are mounted in spaced-apart relation so that the top drive wheel is positioned between the first and second base drive wheels. The mounting arrangement is also such that the first and second base drive wheels contact the inside surface of the pipe at respective first and second positions and so that the top drive wheel contacts the inside surface of the pipe at a third position, the third position being substantially diametrically opposed to the first and second positions. A control system connected to the half tractor assembly controls the rotation of the first base wheel, the second base wheel, and the top drive wheel to move the half tractor assembly within the pipe.

  19. Freezable heat pipe

    DOEpatents

    Ernst, Donald M. (Leola, PA); Sanzi, James L. (Lancaster, PA)

    1981-02-03

    A heat pipe whose fluid can be repeatedly frozen and thawed without damage to the casing. An additional part is added to a conventional heat pipe. This addition is a simple porous structure, such as a cylinder, self-supporting and free standing, which is dimensioned with its diameter not spanning the inside transverse dimension of the casing, and with its length surpassing the depth of maximum liquid.

  20. Simplified pipe gun

    SciTech Connect

    So-dash-barrensen, H.; Nordskov, A.; Sass, B.; Visler, T.

    1987-12-01

    A simplified version of a deuterium pellet gun based on the pipe gun principle is described. The pipe gun is made from a continuous tube of stainless steel and gas is fed in from the muzzle end only. It is indicated that the pellet length is determined by the temperature gradient along the barrel right outside the freezing cell. Velocities of around 1000 m/s with a scatter of +- 2% are obtained with a propellant gas pressure of 40 bar.

  1. Simplified pipe gun

    NASA Astrophysics Data System (ADS)

    Srensen, H.; Nordskov, A.; Sass, B.; Visler, T.

    1987-12-01

    A simplified version of a deuterium pellet gun based on the pipe gun principle is described. The pipe gun is made from a continuous tube of stainless steel and gas is fed in from the muzzle end only. It is indicated that the pellet length is determined by the temperature gradient along the barrel right outside the freezing cell. Velocities of around 1000 m/s with a scatter of 2% are obtained with a propellant gas pressure of 40 bar.

  2. The design of a scalable, fixed-time computer benchmark

    SciTech Connect

    Gustafson, J.; Rover, D.; Elbert, S.; Carter, M.

    1990-10-01

    By using the principle of fixed time benchmarking, it is possible to compare a very wide range of computers, from a small personal computer to the most powerful parallel supercomputer, an a single scale. Fixed-time benchmarks promise far greater longevity than those based on a particular problem size, and are more appropriate for grand challenge'' capability comparison. We present the design of a benchmark, SLALOM{trademark}, that scales automatically to the computing power available, and corrects several deficiencies in various existing benchmarks: it is highly scalable, it solves a real problem, it includes input and output times, and it can be run on parallel machines of all kinds, using any convenient language. The benchmark provides a reasonable estimate of the size of problem solvable on scientific computers. Results are presented that span six orders of magnitude for contemporary computers of various architectures. The benchmarks also can be used to demonstrate a new source of superlinear speedup in parallel computers. 15 refs., 14 figs., 3 tabs.

  3. Analyzing the BBOB results by means of benchmarking concepts.

    PubMed

    Mersmann, O; Preuss, M; Trautmann, H; Bischl, B; Weihs, C

    2015-01-01

    We present methods to answer two basic questions that arise when benchmarking optimization algorithms. The first one is: which algorithm is the "best" one? and the second one is: which algorithm should I use for my real-world problem? Both are connected and neither is easy to answer. We present a theoretical framework for designing and analyzing the raw data of such benchmark experiments. This represents a first step in answering the aforementioned questions. The 2009 and 2010 BBOB benchmark results are analyzed by means of this framework and we derive insight regarding the answers to the two questions. Furthermore, we discuss how to properly aggregate rankings from algorithm evaluations on individual problems into a consensus, its theoretical background and which common pitfalls should be avoided. Finally, we address the grouping of test problems into sets with similar optimizer rankings and investigate whether these are reflected by already proposed test problem characteristics, finding that this is not always the case. PMID:24967695

  4. Benchmarking and Data Analysis

    E-print Network

    Williams, K.

    2014-01-01

    Kellie Williams | Houston ISD ESL-KT-14-11-14 CATEE 2014: Clean Air Through Efficiency Conference, Dallas, Texas Nov. 18-20 Benchmarking ? Process of comparing data sets ? Baselines, Goals, KPIs ? Energy Star Portfolio Manager ESL-KT-14-11-14 CATEE 2014... Efficiency Conference, Dallas, Texas Nov. 18-20 Great data leads to great decisions ESL-KT-14-11-14 CATEE 2014: Clean Air Through Efficiency Conference, Dallas, Texas Nov. 18-20 Resources Energy Star Portfolio Manager http...

  5. Phase Transitions from Real Computational Problems \\Lambda Ian P. Gent Toby Walsh

    E-print Network

    St Andrews, University of

    than ran­ dom problems. Our results suggest a new methodology for benchmarking algorithms. In addition for comparing the per­ formance of algorithms is to use benchmark problems. Since the supply of benchmark prob. For software, benchmark problems and program­ ming assistance, we thank Robert Craig, Ian Frank, Henry Kautz

  6. NAS Parallel Benchmarks. 2.4

    NASA Technical Reports Server (NTRS)

    VanderWijngaart, Rob; Biegel, Bryan A. (Technical Monitor)

    2002-01-01

    We describe a new problem size, called Class D, for the NAS Parallel Benchmarks (NPB), whose MPI source code implementation is being released as NPB 2.4. A brief rationale is given for how the new class is derived. We also describe the modifications made to the MPI (Message Passing Interface) implementation to allow the new class to be run on systems with 32-bit integers, and with moderate amounts of memory. Finally, we give the verification values for the new problem size.

  7. Self-benchmarking Guide for Cleanrooms: Metrics, Benchmarks, Actions

    SciTech Connect

    Mathew, Paul; Sartor, Dale; Tschudi, William

    2009-07-13

    This guide describes energy efficiency metrics and benchmarks that can be used to track the performance of and identify potential opportunities to reduce energy use in laboratory buildings. This guide is primarily intended for personnel who have responsibility for managing energy use in existing laboratory facilities - including facilities managers, energy managers, and their engineering consultants. Additionally, laboratory planners and designers may also use the metrics and benchmarks described in this guide for goal-setting in new construction or major renovation. This guide provides the following information: (1) A step-by-step outline of the benchmarking process. (2) A set of performance metrics for the whole building as well as individual systems. For each metric, the guide provides a definition, performance benchmarks, and potential actions that can be inferred from evaluating this metric. (3) A list and descriptions of the data required for computing the metrics. This guide is complemented by spreadsheet templates for data collection and for computing the benchmarking metrics. This guide builds on prior research supported by the national Laboratories for the 21st Century (Labs21) program, supported by the U.S. Department of Energy and the U.S. Environmental Protection Agency. Much of the benchmarking data are drawn from the Labs21 benchmarking database and technical guides. Additional benchmark data were obtained from engineering experts including laboratory designers and energy managers.

  8. Self-benchmarking Guide for Laboratory Buildings: Metrics, Benchmarks, Actions

    SciTech Connect

    Mathew, Paul; Greenberg, Steve; Sartor, Dale

    2009-07-13

    This guide describes energy efficiency metrics and benchmarks that can be used to track the performance of and identify potential opportunities to reduce energy use in laboratory buildings. This guide is primarily intended for personnel who have responsibility for managing energy use in existing laboratory facilities - including facilities managers, energy managers, and their engineering consultants. Additionally, laboratory planners and designers may also use the metrics and benchmarks described in this guide for goal-setting in new construction or major renovation. This guide provides the following information: (1) A step-by-step outline of the benchmarking process. (2) A set of performance metrics for the whole building as well as individual systems. For each metric, the guide provides a definition, performance benchmarks, and potential actions that can be inferred from evaluating this metric. (3) A list and descriptions of the data required for computing the metrics. This guide is complemented by spreadsheet templates for data collection and for computing the benchmarking metrics. This guide builds on prior research supported by the national Laboratories for the 21st Century (Labs21) program, supported by the U.S. Department of Energy and the U.S. Environmental Protection Agency. Much of the benchmarking data are drawn from the Labs21 benchmarking database and technical guides. Additional benchmark data were obtained from engineering experts including laboratory designers and energy managers.

  9. Explosive Welding of Pipes

    NASA Astrophysics Data System (ADS)

    Burtseva, Olga

    2007-06-01

    For connection by welding it is suggested to use the explosive welding method. This method is rather new. Nevertheless, it has become commonly used among the technological developments. This method can be advantageous (saving material and physical resources) comparing to its statical analogs (electron-beam welding, argon-arc welding, plasma welding, gas welding, etc.), in particular, in hard-to-reach areas due to their geographic and climatic conditions. The suggestion is to use water as filler. The principle of non-compressibility of liquid under quasi-dynamic loading is used. In one-dimensional gasdynamic and elastic-plastic calculations we determined non-deformed mass of water (perturbations, which are moving in the axial direction with sound velocity, should not reach the layer end boundaries for 5-7 circulations of shock waves in the radial direction). Linear dimension of the water layer from the zone of pipe coupling along axis in each direction is >= 2R, where R is the internal radius of pipe. Model experiments with pipes having radii R = 57 mm confirmed results of the calculations and the possibility in principle to weld pipes by explosion with use of water as filler. Reduction of pipe diameter after dynamic loading and explosive welding was 2%.

  10. Remotely operated pipe connector

    DOEpatents

    Josefiak, Leonard J. (Scotia, NY); Cramer, Charles E. (Guilderford, NY)

    1988-01-01

    An apparatus for remotely assembling and disassembling a Graylock type coctor between a pipe and a closure for the pipe includes a base and a receptacle on the base for the closure. The pipe is moved into position vertically above the closure by a suitable positioning device such that the flange on the pipe is immediately adjacent and concentric with the flange on the closure. A moving device then moves two semicircular collars from a position free of the closure to a position such that the interior cam groove of each collar contacts the two flanges. Finally, a tensioning device automatically allows remote tightening and loosening of a nut and bolt assembly on each side of the collar to cause a seal ring located between the flanges to be compressed and to seal the closure. Release of the pipe and the connector is accomplished in the reverse order. Preferably, the nut and bolt assembly includes an elongate shaft portion on which a removable sleeve is located.

  11. Internal Benchmarking for Institutional Effectiveness

    ERIC Educational Resources Information Center

    Ronco, Sharron L.

    2012-01-01

    Internal benchmarking is an established practice in business and industry for identifying best in-house practices and disseminating the knowledge about those practices to other groups in the organization. Internal benchmarking can be done with structures, processes, outcomes, or even individuals. In colleges or universities with multicampuses or a

  12. Former Yosemite Hydrologic Benchmark Streamgage

    USGS Multimedia Gallery

    In this image, the former USGS Hydrologic Benchmark Streamgage on the Merced River in Yosemite Valley can be seen. Hydrologic Benchmark streamgages are those at which no human development exists upstream of the streamgage. The streamgage station has been in existence since 1915, and was replaced by ...

  13. NAS Grid Benchmarks: A Tool for Grid Space Exploration

    NASA Technical Reports Server (NTRS)

    Frumkin, Michael; VanderWijngaart, Rob F.; Biegel, Bryan (Technical Monitor)

    2001-01-01

    We present an approach for benchmarking services provided by computational Grids. It is based on the NAS Parallel Benchmarks (NPB) and is called NAS Grid Benchmark (NGB) in this paper. We present NGB as a data flow graph encapsulating an instance of an NPB code in each graph node, which communicates with other nodes by sending/receiving initialization data. These nodes may be mapped to the same or different Grid machines. Like NPB, NGB will specify several different classes (problem sizes). NGB also specifies the generic Grid services sufficient for running the bench-mark. The implementor has the freedom to choose any specific Grid environment. However, we describe a reference implementation in Java, and present some scenarios for using NGB.

  14. 49 CFR 230.62 - Dry pipe.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 4 2011-10-01 2011-10-01 false Dry pipe. 230.62 Section 230.62 Transportation...MAINTENANCE STANDARDS Boilers and Appurtenances Steam Pipes 230.62 Dry pipe. Dry pipes subject to pressure shall be...

  15. 49 CFR 230.62 - Dry pipe.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 4 2010-10-01 2010-10-01 false Dry pipe. 230.62 Section 230.62 Transportation...MAINTENANCE STANDARDS Boilers and Appurtenances Steam Pipes 230.62 Dry pipe. Dry pipes subject to pressure shall be...

  16. FireHose Streaming Benchmarks

    SciTech Connect

    2015-01-27

    The FireHose Streaming Benchmarks are a suite of stream-processing benchmarks defined to enable comparison of streaming software and hardware, both quantitatively vis-a-vis the rate at which they can process data, and qualitatively by judging the effort involved to implement and run the benchmarks. Each benchmark has two parts. The first is a generator which produces and outputs datums at a high rate in a specific format. The second is an analytic which reads the stream of datums and is required to perform a well-defined calculation on the collection of datums, typically to find anomalous datums that have been created in the stream by the generator. The FireHose suite provides code for the generators, sample code for the analytics (which users are free to re-implement in their own custom frameworks), and a precise definition of each benchmark calculation.

  17. Aircraft Engine Gas Path Diagnostic Methods: Public Benchmarking Results

    NASA Technical Reports Server (NTRS)

    Simon, Donald L.; Borguet, Sebastien; Leonard, Olivier; Zhang, Xiaodong (Frank)

    2013-01-01

    Recent technology reviews have identified the need for objective assessments of aircraft engine health management (EHM) technologies. To help address this issue, a gas path diagnostic benchmark problem has been created and made publicly available. This software tool, referred to as the Propulsion Diagnostic Method Evaluation Strategy (ProDiMES), has been constructed based on feedback provided by the aircraft EHM community. It provides a standard benchmark problem enabling users to develop, evaluate and compare diagnostic methods. This paper will present an overview of ProDiMES along with a description of four gas path diagnostic methods developed and applied to the problem. These methods, which include analytical and empirical diagnostic techniques, will be described and associated blind-test-case metric results will be presented and compared. Lessons learned along with recommendations for improving the public benchmarking processes will also be presented and discussed.

  18. A Novel Pre-cooling System for a Cryogenic Pulsating Heat Pipe

    NASA Astrophysics Data System (ADS)

    Xu, Dong; Liu, Huiming; Gong, Linghui; Xu, Xiangdong; Li, Laifeng

    To reduce the influence of the pipe material on the measurement of effective thermal conductivity, the pipe of a cryogenic pulsating heat pipe is generally made of stainless steel. Because of the low thermal conductivity of stainless steel, the pre-cooling of the evaporator in cryogenic pulsating heat pipe using helium as working fluid at 4.2 K is a problem. We designed a mechanical-thermal switch between the cryocooler and the evaporator, which was on during the pre-cooling process and off during the test process. By using the pre-cooling system, the cool down time of the cryogenic pulsating heat pipe was reduced significantly.

  19. Apparatus for moving a pipe inspection probe through piping

    DOEpatents

    Zollinger, W.T.; Appel, D.K.; Lewis, G.W.

    1995-07-18

    A method and apparatus are disclosed for controllably moving devices for cleaning or inspection through piping systems, including piping systems with numerous piping bends therein, by using hydrostatic pressure of a working fluid introduced into the piping system. The apparatus comprises a reservoir or other source for supplying the working fluid to the piping system, a launch tube for admitting the device into the launcher and a reversible, positive displacement pump for controlling the direction and flow rate of the working fluid. The device introduced into the piping system moves with the flow of the working fluid through the piping system. The launcher attaches to the valved ends of a piping system so that fluids in the piping system can recirculate in a closed loop. The method comprises attaching the launcher to the piping system, supplying the launcher with working fluid, admitting the device into the launcher, pumping the working fluid in the direction and at the rate desired so that the device moves through the piping system for pipe cleaning or inspection, removing the device from the launcher, and collecting the working fluid contained in the launcher. 8 figs.

  20. Heat pipes and use of heat pipes in furnace exhaust

    DOEpatents

    Polcyn, Adam D. (Pittsburgh, PA)

    2010-12-28

    An array of a plurality of heat pipe are mounted in spaced relationship to one another with the hot end of the heat pipes in a heated environment, e.g. the exhaust flue of a furnace, and the cold end outside the furnace. Heat conversion equipment is connected to the cold end of the heat pipes.

  1. Apparatus for moving a pipe inspection probe through piping

    DOEpatents

    Zollinger, W. Thor (Martinez, GA); Appel, D. Keith (Aiken, SC); Lewis, Gregory W. (North Augusta, SC)

    1995-01-01

    A method and apparatus for controllably moving devices for cleaning or inspection through piping systems, including piping systems with numerous piping bends therein, by using hydrostatic pressure of a working fluid introduced into the piping system. The apparatus comprises a reservoir or other source for supplying the working fluid to the piping system, a launch tube for admitting the device into the launcher and a reversible, positive displacement pump for controlling the direction and flow rate of the working fluid. The device introduced into the piping system moves with the flow of the working fluid through the piping system. The launcher attaches to the valved ends of a piping system so that fluids in the piping system can recirculate in a closed loop. The method comprises attaching the launcher to the piping system, supplying the launcher with working fluid, admitting the device into the launcher, pumping the working fluid in the direction and at the rate desired so that the device moves through the piping system for pipe cleaning or inspection, removing the device from the launcher, and collecting the working fluid contained in the launcher.

  2. Apparatus for inspecting piping

    DOEpatents

    Zollingger, W. Thor (Martinez, GA); Appel, D. Keith (Aiken, SC); Park, Larry R. (Raleigh, NC)

    1995-01-01

    An inspection rabbit for inspecting piping systems having severe bends therein. The rabbit consists of a flexible, modular body containing a miniaturized eddy current inspection probe, a self-contained power supply for proper operation of the rabbit, an outer surface that allows ease of movement through piping systems and means for transmitting data generated by the inspection device. The body is preferably made of flexible polyvinyl chloride (PVC) tubing or, alternatively, silicone rubber with a shrink wrapping of polytetrafluoroethylene (TEFLON.RTM.). The body is formed to contain the power supply, preferably a plurality of batteries, and a spool of communication wire that connects to a data processing computer external to the piping system.

  3. Apparatus for inspecting piping

    DOEpatents

    Zollingger, W.T.; Appel, D.K.; Park, L.R.

    1995-03-21

    An inspection rabbit is described for inspecting piping systems having severe bends therein. The rabbit consists of a flexible, modular body containing a miniaturized eddy current inspection probe, a self-contained power supply for proper operation of the rabbit, an outer surface that allows ease of movement through piping systems and means for transmitting data generated by the inspection device. The body is preferably made of flexible polyvinyl chloride (PVC) tubing or, alternatively, silicone rubber with a shrink wrapping of polytetrafluoroethylene (TEFLON{trademark}). The body is formed to contain the power supply, preferably a plurality of batteries, and a spool of communication wire that connects to a data processing computer external to the piping system. 6 figures.

  4. Heat-pipe Earth.

    PubMed

    Moore, William B; Webb, A Alexander G

    2013-09-26

    The heat transport and lithospheric dynamics of early Earth are currently explained by plate tectonic and vertical tectonic models, but these do not offer a global synthesis consistent with the geologic record. Here we use numerical simulations and comparison with the geologic record to explore a heat-pipe model in which volcanism dominates surface heat transport. These simulations indicate that a cold and thick lithosphere developed as a result of frequent volcanic eruptions that advected surface materials downwards. Declining heat sources over time led to an abrupt transition to plate tectonics. Consistent with model predictions, the geologic record shows rapid volcanic resurfacing, contractional deformation, a low geothermal gradient across the bulk of the lithosphere and a rapid decrease in heat-pipe volcanism after initiation of plate tectonics. The heat-pipe Earth model therefore offers a coherent geodynamic framework in which to explore the evolution of our planet before the onset of plate tectonics. PMID:24067709

  5. Composite drill pipe

    DOEpatents

    Leslie, James C. (Fountain Valley, CA); Leslie, II, James C. (Mission Viejo, CA); Heard, James (Huntington Beach, CA); Truong, Liem (Anaheim, CA), Josephson; Marvin (Huntington Beach, CA), Neubert; Hans (Anaheim, CA)

    2008-12-02

    A composite pipe segment is formed to include tapered in wall thickness ends that are each defined by opposed frustoconical surfaces conformed for self centering receipt and intimate bonding contact within an annular space between corresponding surfaces of a coaxially nested set of metal end pieces. The distal peripheries of the nested end pieces are then welded to each other and the sandwiched and bonded portions are radially pinned. The composite segment may include imbedded conductive leads and the axial end portions of the end pieces are shaped to form a threaded joint with the next pipe assembly that includes a contact ring in one pipe assembly pierced by a pointed contact in the other to connect the corresponding leads across the joint.

  6. Benchmarking foreign electronics technologies

    SciTech Connect

    Bostian, C.W.; Hodges, D.A.; Leachman, R.C.; Sheridan, T.B.; Tsang, W.T.; White, R.M.

    1994-12-01

    This report has been drafted in response to a request from the Japanese Technology Evaluation Center`s (JTEC) Panel on Benchmarking Select Technologies. Since April 1991, the Competitive Semiconductor Manufacturing (CSM) Program at the University of California at Berkeley has been engaged in a detailed study of quality, productivity, and competitiveness in semiconductor manufacturing worldwide. The program is a joint activity of the College of Engineering, the Haas School of Business, and the Berkeley Roundtable on the International Economy, under sponsorship of the Alfred P. Sloan Foundation, and with the cooperation of semiconductor producers from Asia, Europe and the United States. Professors David A. Hodges and Robert C. Leachman are the project`s Co-Directors. The present report for JTEC is primarily based on data and analysis drawn from that continuing program. The CSM program is being conducted by faculty, graduate students and research staff from UC Berkeley`s Schools of Engineering and Business, and Department of Economics. Many of the participating firms are represented on the program`s Industry Advisory Board. The Board played an important role in defining the research agenda. A pilot study was conducted in 1991 with the cooperation of three semiconductor plants. The research plan and survey documents were thereby refined. The main phase of the CSM benchmarking study began in mid-1992 and will continue at least through 1997. reports are presented on the manufacture of integrated circuits; data storage; wireless technology; human-machine interfaces; and optoelectronics. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

  7. Heat pipe array heat exchanger

    DOEpatents

    Reimann, Robert C. (Lafayette, NY)

    1987-08-25

    A heat pipe arrangement for exchanging heat between two different temperature fluids. The heat pipe arrangement is in a ounterflow relationship to increase the efficiency of the coupling of the heat from a heat source to a heat sink.

  8. Pipe Flow System Holly Guest

    E-print Network

    Clement, Prabhakar

    of a given pipe system involving two reservoirs and to make recommendations based on the outputs on how to improve the design. Inputs include: Head of each reservoir Head of the pump Pipe Diameter using

  9. Superfluid Helium Heat Pipe

    NASA Astrophysics Data System (ADS)

    Gully, P.

    This paper reports on the development and the thermal tests of three superfluid helium heat pipes. Two of them are designed to provide a large transport capacity (4 mW at 1.7 K). They feature a copper braid located inside a 6 mm outer diameter stainless tube fitted with copper ends for mechanical anchoring. The other heat pipe has no copper braid and is designed to get much smaller heat transport capacity (0.5 mW) and to explore lower temperature (0.7 - 1 K). The copper braid and the tube wall is the support of the Rollin superfluid helium film in which the heat is transferred. The low filling pressure makes the technology very simple with the possibility to easily bend the tube. We present the design and discuss the thermal performance of the heat pipes tested in the 0.7 to 2.0 K temperature range. The long heat pipe (1.2 m with copper braid) and the short one (0.25 m with copper braid) have similar thermal performance in the range 0.7 - 2.0 K. At 1.7 K the long heat pipe, 120 g in weight, reaches a heat transfer capacity of 6.2 mW and a thermal conductance of 600 mW/K for 4 mW transferred power. Due to the pressure drop of the vapor flow and Kapitza thermal resistance, the conductance of the third heat pipe dramatically decreases when the temperature decreases. A 3.8 mW/K is obtained at 0.7 K for 0.5 mW transferred power.

  10. On a new benchmark for the simulation of saltwater intrusion

    NASA Astrophysics Data System (ADS)

    Stoeckl, Leonard; Graf, Thomas

    2015-04-01

    To date, many different benchmark problems for density-driven flow are available. Benchmarks are necessary to validate numerical models. The benchmark by Henry (1964) measures a saltwater wedge, intruding into a freshwater aquifer in a rectangular model. The Henry (1964) problem of saltwater intrusion is one of the most applied benchmarks in hydrogeology. Modelling saltwater intrusion will be of major importance in the future because investigating the impact of groundwater overexploitation, climate change or sea level rise are of key concern. The worthiness of the Henry (1964) problem was questioned by Simpson and Clement (2003), who compared density-coupled and density-uncoupled simulations. Density-uncoupling was achieved by neglecting density effects in the governing equations, and by considering density effects only in the flow boundary conditions. As both of their simulations showed similar results, Simpson and Clement (2003) concluded that flow patterns of the Henry (1964) problem are largely dictated by the applied flow boundary conditions and density-dependent effects are not adequately represented in the Henry (1964) problem. In the present study, we compare numerical simulations of the physical benchmark of a freshwater lens by Stoeckl and Houben (2012) to the Henry (1964) problem. In this new benchmark, the development of a freshwater lens under an island is simulated by applying freshwater recharge to the model top. Results indicate that density-uncoupling significantly alters the flow patterns of fresh- and saltwater. This leads to the conclusion that next to the boundary conditions applied, density-dependent effects are important to correctly simulate the flow dynamics of a freshwater lens.

  11. Heat transfer in pipes

    NASA Technical Reports Server (NTRS)

    Burbach, T.

    1985-01-01

    The heat transfer from hot water to a cold copper pipe in laminar and turbulent flow condition is determined. The mean flow through velocity in the pipe, relative test length and initial temperature in the vessel were varied extensively during tests. Measurements confirm Nusselt's theory for large test lengths in laminar range. A new equation is derived for heat transfer for large starting lengths which agrees satisfactorily with measurements for large starting lengths. Test results are compared with the new Prandtl equation for heat transfer and correlated well. Test material for 200- and to 400-diameter test length is represented at four different vessel temperatures.

  12. Pipe Drafting with CAD. Teacher Edition.

    ERIC Educational Resources Information Center

    Smithson, Buddy

    This teacher's guide contains nine units of instruction for a course on computer-assisted pipe drafting. The course covers the following topics: introduction to pipe drafting with CAD (computer-assisted design); flow diagrams; pipe and pipe components; valves; piping plans and elevations; isometrics; equipment fabrication drawings; piping design

  13. Loop Heat Pipe for Electronics

    E-print Network

    Lee, Ho Sung

    Loop Heat Pipe for Electronics Dr. HoSung Lee April 15, 2015 #12;Fujitsu Laboratories Ltd. Figure 1: Configuration of a loop heat pipe Figure 2: New thermal management concept for a smartphone equipped with a loop heat pipe Figure 4: Etched pattern of the evaporator section in an inner layer sheet (The evaporator

  14. Benchmarking in the sunshine state

    SciTech Connect

    Varella, F.

    1996-09-01

    Comparably sized municipal electric utilities in Florida have assembled a group to benchmark key performance areas. There are many benchmarking or performance measurement groups striving to identify best business practices in an effort to keep companies flourishing in these tough times. As the work forces shrink and workloads increase, these tools are critical for managerial analysis. Over the pat couple of years, Fort Pierce Utilities Authority in Florida has been involved in the initial benchmarking process of the American Public Power Association, the results of which are documented in the June 1994 publication entitled Benchmarking for Electric Utilities: Report of APP`s Benchmarking Task Force. This report provided the foundation to establish a benchmarking group in Florida that would be relevant to and characteristic of the public power industry in the state. Using the expertise of a consultant, R.W. Beck of Orlando, and the Florida Municipal Power Agency, the group pursued the idea of developing a database from Florida municipal electric utilities of similar size (annual sales over 100 gWh hours, but less than 1,000 gWh) for the purpose of establishing performance benchmarks. The results of this study are discussed.

  15. Defect characterization in pipe-to-pipe welds in large diameter stainless steel piping

    SciTech Connect

    Rawl, D.E. Jr.; West, S.L.; Wheeler, D.A.; Louthan, M.R. Jr.

    1990-01-01

    Metallurgical evaluation of pipe-to-pipe welds in large-diameter, Type 304 stainless steel piping used to construct the moderator/coolant water systems for Savannah River Site reactors has demonstrated that small weld defects found in this 1950-vintage system do not compromise the integrity of the system. The weld defects were too small for detection by the pre-service standard radiographic inspection, but were found through systematic ultrasonic testing (UT) and penetrant testing (PT) evaluations of piping that had been removed during upgrades to the piping system. The defects include lack of weld penetration, slag inclusions, and other weld metal discontinuities. These discontinuities typically did not propagate during more than 35 years of service. The defects examined were too small and isolated to degrade the mechanical properties of the pipe-to-pipe weldments and therefore did not compromise the integrity of the piping system. 14 refs., 7 figs.

  16. Benchmarking numerical freeze/thaw models

    NASA Astrophysics Data System (ADS)

    Rhaak, Wolfram; Anbergen, Hauke; Molson, John; Grenier, Christophe; Sass, Ingo

    2015-04-01

    The modeling of freezing and thawing of water in porous media is of increasing interest, and for which very different application areas exist. For instance, the modeling of permafrost regression with respect to climate change issues is one area, while others include geotechnical applications in tunneling and for borehole heat exchangers which operate at temperatures below the freezing point. The modeling of these processes requires the solution of a coupled non-linear system of partial differential equations for flow and heat transport in space and time. Different code implementations have been developed in the past. Analytical solutions exist only for simple cases. Consequently, an interest has arisen in benchmarking different codes with analytical solutions, experiments and purely numerical results, similar to the long-standing DECOVALEX and the more recent "Geothermal Code Comparison" activities. The name for this freezing/ thawing benchmark consortium is INTERFROST. In addition to the well-known so-called Lunardini solution for a 1D case (case T1), two different 2D problems will be presented, one which represents melting of a frozen inclusion (case TH2) and another which represents the growth or thaw of permafrost around a talik (case TH3). These talik regions are important for controlling groundwater movement within a mainly frozen ground. First results of the different benchmark results will be shown and discussed.

  17. Techniques associated with thermal-vacuum testing of the OAO C heat pipes

    NASA Technical Reports Server (NTRS)

    Marshburn, J. P.

    1972-01-01

    The mechanical problems associated with the testing of two heat pipes installed in the OAO C spacecraft are described. The test problems discussed concern the specially designed heat removal devices, the mobile tilt table, the table position indicator, and the heat input machanisms. It was determined that the techniques used were adequate for thermal-vacuum testing of heat pipes.

  18. 46 CFR 154.503 - Piping and piping system components: Protection from movement.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Piping and piping system components: Protection from..., Construction and Equipment Cargo and Process Piping Systems 154.503 Piping and piping system components... cause stresses that exceed the design stresses, the piping and piping system components and cargo...

  19. 46 CFR 154.503 - Piping and piping system components: Protection from movement.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Piping and piping system components: Protection from..., Construction and Equipment Cargo and Process Piping Systems 154.503 Piping and piping system components... cause stresses that exceed the design stresses, the piping and piping system components and cargo...

  20. 46 CFR 154.503 - Piping and piping system components: Protection from movement.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Piping and piping system components: Protection from..., Construction and Equipment Cargo and Process Piping Systems 154.503 Piping and piping system components... cause stresses that exceed the design stresses, the piping and piping system components and cargo...

  1. 46 CFR 154.503 - Piping and piping system components: Protection from movement.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Piping and piping system components: Protection from..., Construction and Equipment Cargo and Process Piping Systems 154.503 Piping and piping system components... cause stresses that exceed the design stresses, the piping and piping system components and cargo...

  2. 46 CFR 154.503 - Piping and piping system components: Protection from movement.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Piping and piping system components: Protection from..., Construction and Equipment Cargo and Process Piping Systems 154.503 Piping and piping system components... cause stresses that exceed the design stresses, the piping and piping system components and cargo...

  3. Precise Regression Benchmarking with Random Effects: Improving Mono Benchmark Results

    E-print Network

    Kent, University of

    Kalibera and Petr Tuma Distributed Systems Research Group, Department of Software Engineering Faculty-221914232, fax +420-221914323 {kalibera,tuma}@nenya.ms.mff.cuni.cz Abstract. Benchmarking as a method

  4. BCSC Screening Performance Benchmarks: Benchmarks for (2007 Data)

    Cancer.gov

    Skip to Main Content Home | Data | Statistics | Tools | Collaborations | Work with Us | Publications | About | Links Benchmarks for Cancers for Screening Mammography Examinations from 1996 - 2005 --- based on BCSC data

  5. BCSC Screening Performance Benchmarks: Benchmarks for Cancers (2009 Data)

    Cancer.gov

    Skip to Main Content Home | Data | Statistics | Tools | Collaborations | Work with Us | Publications | About | Links Benchmarks for Cancers for Screening Mammography Examinations from 2004 - 2008 -- based on BCSC data

  6. Acme jumper pipe

    SciTech Connect

    Medved, P.; Thomas, H.

    1995-09-01

    Acme Steel had operated the larry car with an attached jumper pipe since 1977. Acme had been able to meet the State Implementation Plan. With the advent of the Clean Air Act, Acme did not feel it could meet these new standards without some modifications to the jumper pipe system. Several drop sleeve modifications and numerous boot seal materials and configurations were tested that resulted in limited success in improving the boot seal life. After these modifications, Acme`s testing revealed it could meet the Clean Air Act standards, but it would be cost prohibitive to continue to operate in this manner. Following extensive investigation, Acme decided to install an off-car jumper pipe system which uses a traveling U-tube for connecting to the assist oven through an additional hole in each oven roof. Temperature related failures of drop sleeve seals were eliminated. The off-car jumper pipe is a more efficient gas connection to the assist oven and enables Acme to meet the Clean Air Act charging requirements in a cost effective manner.

  7. Explosive Welding of Pipes

    NASA Astrophysics Data System (ADS)

    Drennov, Oleg; Drennov, Andrey; Burtseva, Olga

    2013-06-01

    For connection by welding it is suggested to use the explosive welding method. This method is rather new. Nevertheless, it has become commonly used among the technological developments. This method can be advantageous (saving material and physical resources) comparing to its statical analogs (electron-beam welding, argon-arc welding, plasma welding, gas welding, etc.), in particular, in hard-to-reach areas due to their geographic and climatic conditions. Explosive welding of cylindrical surfaces is performed by launching of welded layer along longitudinal axis of construction. During this procedure, it is required to provide reliable resistance against radial convergent strains. The traditional method is application of fillers of pipe cavity, which are dense cylindrical objects having special designs. However, when connecting pipes consecutively in pipelines by explosive welding, removal of the fillers becomes difficult and sometimes impossible. The suggestion is to use water as filler. The principle of non-compressibility of liquid under quasi-dynamic loading is used. In one-dimensional gasdynamic and elastic-plastic calculations we determined non-deformed mass of water (perturbations, which are moving in the axial direction with sound velocity, should not reach the layer end boundaries for 5-7 circulations of shock waves in the radial direction). Linear dimension of the water layer from the zone of pipe coupling along axis in each direction is >= 2R, where R is the internal radius of pipe.

  8. California commercial building energy benchmarking

    SciTech Connect

    Kinney, Satkartar; Piette, Mary Ann

    2003-07-01

    Building energy benchmarking is the comparison of whole-building energy use relative to a set of similar buildings. It provides a useful starting point for individual energy audits and for targeting buildings for energy-saving measures in multiple-site audits. Benchmarking is of interest and practical use to a number of groups. Energy service companies and performance contractors communicate energy savings potential with ''typical'' and ''best-practice'' benchmarks while control companies and utilities can provide direct tracking of energy use and combine data from multiple buildings. Benchmarking is also useful in the design stage of a new building or retrofit to determine if a design is relatively efficient. Energy managers and building owners have an ongoing interest in comparing energy performance to others. Large corporations, schools, and government agencies with numerous facilities also use benchmarking methods to compare their buildings to each other. The primary goal of Task 2.1.1 Web-based Benchmarking was the development of a web-based benchmarking tool, dubbed Cal-Arch, for benchmarking energy use in California commercial buildings. While there were several other benchmarking tools available to California consumers prior to the development of Cal-Arch, there were none that were based solely on California data. Most available benchmarking information, including the Energy Star performance rating, were developed using DOE's Commercial Building Energy Consumption Survey (CBECS), which does not provide state-level data. Each database and tool has advantages as well as limitations, such as the number of buildings and the coverage by type, climate regions and end uses. There is considerable commercial interest in benchmarking because it provides an inexpensive method of screening buildings for tune-ups and retrofits. However, private companies who collect and manage consumption data are concerned that the identities of building owners might be revealed and hence are reluctant to share their data. The California Commercial End Use Survey (CEUS), the primary source of data for Cal-Arch, is a unique source of information on commercial buildings in California. It has not been made public; however, it was made available by CEC to LBNL for the purpose of developing a public benchmarking tool.

  9. Seismic response reduction of a piping system by a dynamic vibration absorber

    SciTech Connect

    Ogawa, Nobuyuki; Kobayashi, Hiroe

    1995-11-01

    A number of studies have been conducted on seismic response reduction technique of piping systems. Among them, seismic supports including elastic-plastic damping devices are rapidly being developed for real application. Dynamic vibration absorbers, which are directly attached to pipe, provide another technique for seismic response reduction. When they are successfully applied to a piping system, they can reduce the number of supports with rigid structures and can be useful for improvement of piping layout. In order to obtain above improvements by the dynamic vibration absorbers, its effectiveness in reducing the large vibration response of the piping system must be verified under the strong earthquake condition. Typical problems to be solved are strength of device against strong excitation, adaptation for multimode`s vibration of pipe, and performance with non-linear behavior of pipe system. Shake table tests are very effective to investigate these problems. The authors have developed a dynamic vibration absorber which uses an air cylinder coil spring and magnetic damping devices and applied it to a real scale piping model. Vibration test results using 3-dimensional piping model have shown the good performance of the absorber, although some problems remain to be solved before actual application. In this paper the authors report the performance of this newly developed dynamic vibration absorber for seismic response reduction of piping systems.

  10. Utilizing clad piping to improve process plant piping integrity, reliability, and operations

    SciTech Connect

    Chakravarti, B.

    1996-07-01

    During the past four years carbon steel piping clad with type 304L (UNS S30403) stainless steel has been used to solve the flow accelerated corrosion (FAC) problem in nuclear power plants with exceptional success. The product is designed to allow ``like for like`` replacement of damaged carbon steel components where the carbon steel remains the pressure boundary and type 304L (UNS S30403) stainless steel the corrosion allowance. More than 3000 feet of piping and 500 fittings in sizes from 6 to 36-in. NPS have been installed in the extraction steam and other lines of these power plants to improve reliability, eliminate inspection program, reduce O and M costs and provide operational benefits. This concept of utilizing clad piping in solving various corrosion problems in industrial and process plants by conservatively selecting a high alloy material as cladding can provide similar, significant benefits in controlling corrosion problems, minimizing maintenance cost, improving operation and reliability to control performance and risks in a highly cost effective manner. This paper will present various material combinations and applications that appear ideally suited for use of the clad piping components in process plants.

  11. Eddy currents benchmark analysis with COMSOL

    NASA Astrophysics Data System (ADS)

    Etcheverry, Javier I.; Ziella, Daniel H.

    2014-02-01

    Several benchmark studies in eddy currents have been proposed by the WFNDEC. Also, there are many analytical exact and approximate solution of interest to quantitatively evaluate the capability of numerical codes to predict the magnitude of the induced currents effects. In this paper we present the results obtained using COMSOL for a representative set of cases of interest. We analyze the accuracy of the results, but also the elements we believe are relevant from the perspective of the NDE specialist (simplicity, computer requirements, things to take into account to get good results, problems faced when solving, failures, etc.).

  12. Correlational effect size benchmarks.

    PubMed

    Bosco, Frank A; Aguinis, Herman; Singh, Kulraj; Field, James G; Pierce, Charles A

    2015-03-01

    Effect size information is essential for the scientific enterprise and plays an increasingly central role in the scientific process. We extracted 147,328 correlations and developed a hierarchical taxonomy of variables reported in Journal of Applied Psychology and Personnel Psychology from 1980 to 2010 to produce empirical effect size benchmarks at the omnibus level, for 20 common research domains, and for an even finer grained level of generality. Results indicate that the usual interpretation and classification of effect sizes as small, medium, and large bear almost no resemblance to findings in the field, because distributions of effect sizes exhibit tertile partitions at values approximately one-half to one-third those intuited by Cohen (1988). Our results offer information that can be used for research planning and design purposes, such as producing better informed non-nil hypotheses and estimating statistical power and planning sample size accordingly. We also offer information useful for understanding the relative importance of the effect sizes found in a particular study in relationship to others and which research domains have advanced more or less, given that larger effect sizes indicate a better understanding of a phenomenon. Also, our study offers information about research domains for which the investigation of moderating effects may be more fruitful and provide information that is likely to facilitate the implementation of Bayesian analysis. Finally, our study offers information that practitioners can use to evaluate the relative effectiveness of various types of interventions. PMID:25314367

  13. Virtual machine performance benchmarking.

    PubMed

    Langer, Steve G; French, Todd

    2011-10-01

    The attractions of virtual computing are many: reduced costs, reduced resources and simplified maintenance. Any one of these would be compelling for a medical imaging professional attempting to support a complex practice on limited resources in an era of ever tightened reimbursement. In particular, the ability to run multiple operating systems optimized for different tasks (computational image processing on Linux versus office tasks on Microsoft operating systems) on a single physical machine is compelling. However, there are also potential drawbacks. High performance requirements need to be carefully considered if they are to be executed in an environment where the running software has to execute through multiple layers of device drivers before reaching the real disk or network interface. Our lab has attempted to gain insight into the impact of virtualization on performance by benchmarking the following metrics on both physical and virtual platforms: local memory and disk bandwidth, network bandwidth, and integer and floating point performance. The virtual performance metrics are compared to baseline performance on "bare metal." The results are complex, and indeed somewhat surprising. PMID:21207096

  14. Memory-Intensive Benchmarks: IRAM vs. Cache-Based Machines

    NASA Technical Reports Server (NTRS)

    Biswas, Rupak; Gaeke, Brian R.; Husbands, Parry; Li, Xiaoye S.; Oliker, Leonid; Yelick, Katherine A.; Biegel, Bryan (Technical Monitor)

    2002-01-01

    The increasing gap between processor and memory performance has lead to new architectural models for memory-intensive applications. In this paper, we explore the performance of a set of memory-intensive benchmarks and use them to compare the performance of conventional cache-based microprocessors to a mixed logic and DRAM processor called VIRAM. The benchmarks are based on problem statements, rather than specific implementations, and in each case we explore the fundamental hardware requirements of the problem, as well as alternative algorithms and data structures that can help expose fine-grained parallelism or simplify memory access patterns. The benchmarks are characterized by their memory access patterns, their basic control structures, and the ratio of computation to memory operation.

  15. Memory-intensive benchmarks: IRAM vs. cache-based machines

    SciTech Connect

    Gaeke, Brian G.; Husbands, Parry; Kim, Hyun Jin; Li, Xiaoye S.; Moon, Hyun Jin; Oliker, Leonid; Yelick, Katherine A.; Biswas, Rupak

    2001-09-29

    The increasing gap between processor and memory performance has led to new architectural models for memory-intensive applications. In this paper, we explore the performance of a set of memory-intensive benchmarks and use them to compare the performance of conventional cache-based microprocessors to a mixed logic and DRAM processor called VIRAM. The benchmarks are based on problem statements, rather than specific implementations, and in each case we explore the fundamental hardware requirements of the problem, as well as alternative algorithms and data structures that can help expose fine-grained parallelism or simplify memory access patterns. The benchmarks are characterized by their memory access patterns, their basic structures, and the ratio of computation to memory operation.

  16. Outlook for Industrial Energy Benchmarking

    E-print Network

    Hartley, Z.

    2000-01-01

    The U.S. Environmental Protection Agency is exploring options to sponsor an industrial energy efficiency benchmarking study to identify facility specific, cost-effective best practices and technologies. Such a study could help develop a common...

  17. Performance Benchmarks for Screening Mammography

    Cancer.gov

    Rosenberg RD, Yankaskas BC, Abraham LA, Sickles EA, Lehman CD, Geller BM, Carney PA, Kerlikowske K, Buist DS, Weaver DL, Barlow WE, Ballard-Barbash R. Performance benchmarks for screening mammography.

  18. Aiming for Benchmark Accuracy with the Many-Body Expansion Ryan M. Richard,

    E-print Network

    Herbert, John

    Aiming for Benchmark Accuracy with the Many-Body Expansion Ryan M. Richard, Ka Un Lao, and John M of these methods for large systems, with the goal of reproducing benchmark-quality calculations, ideally meaning the possibility of serious loss-of-precision problems that are not widely appreciated. Tight thresholds

  19. PHYSICAL REVIEW A 91, 032501 (2015) Quantum critical benchmark for electronic structure theory

    E-print Network

    Burke, Kieron

    2015-01-01

    PHYSICAL REVIEW A 91, 032501 (2015) Quantum critical benchmark for electronic structure theory Paul. INTRODUCTION The value of highly accurate benchmark calculations to first-principles electronic structure nontrivial quantum systems and so serves as a common test problem for electronic structure methods, from

  20. Benchmarking hypercube hardware and software

    NASA Technical Reports Server (NTRS)

    Grunwald, Dirk C.; Reed, Daniel A.

    1986-01-01

    It was long a truism in computer systems design that balanced systems achieve the best performance. Message passing parallel processors are no different. To quantify the balance of a hypercube design, an experimental methodology was developed and the associated suite of benchmarks was applied to several existing hypercubes. The benchmark suite includes tests of both processor speed in the absence of internode communication and message transmission speed as a function of communication patterns.

  1. Benchmarking, BOMA BESt and BBEER

    E-print Network

    Smiciklas, J.

    2013-01-01

    ?have?a?strong? commitment?to?implementing? effective?management?practices?for? hazardous?materials?and?products. Benchmarking and BBEER 2013 BBEER 2013 RESULTS: INDOOR ENVIRONMENT (Office) ? BOMA?BESt?certified? buildings?across?the?country? achieve... BESt and BBEER John Smiciklas Director, Energy and Sustainability BENCHMARKING ? What and Why? Ongoing?review?of?energy?consumption?to?answer?the?question: ?Is?my?building?s?energy?performance? better?or?worse?than?????? Energy...

  2. Benchmarks for GADRAS performance validation.

    SciTech Connect

    Mattingly, John K.; Mitchell, Dean James; Rhykerd, Charles L., Jr.

    2009-09-01

    The performance of the Gamma Detector Response and Analysis Software (GADRAS) was validated by comparing GADRAS model results to experimental measurements for a series of benchmark sources. Sources for the benchmark include a plutonium metal sphere, bare and shielded in polyethylene, plutonium oxide in cans, a highly enriched uranium sphere, bare and shielded in polyethylene, a depleted uranium shell and spheres, and a natural uranium sphere. The benchmark experimental data were previously acquired and consist of careful collection of background and calibration source spectra along with the source spectra. The calibration data were fit with GADRAS to determine response functions for the detector in each experiment. A one-dimensional model (pie chart) was constructed for each source based on the dimensions of the benchmark source. The GADRAS code made a forward calculation from each model to predict the radiation spectrum for the detector used in the benchmark experiment. The comparisons between the GADRAS calculation and the experimental measurements are excellent, validating that GADRAS can correctly predict the radiation spectra for these well-defined benchmark sources.

  3. Research on computer systems benchmarking

    NASA Technical Reports Server (NTRS)

    Smith, Alan Jay (Principal Investigator)

    1996-01-01

    This grant addresses the topic of research on computer systems benchmarking and is more generally concerned with performance issues in computer systems. This report reviews work in those areas during the period of NASA support under this grant. The bulk of the work performed concerned benchmarking and analysis of CPUs, compilers, caches, and benchmark programs. The first part of this work concerned the issue of benchmark performance prediction. A new approach to benchmarking and machine characterization was reported, using a machine characterizer that measures the performance of a given system in terms of a Fortran abstract machine. Another report focused on analyzing compiler performance. The performance impact of optimization in the context of our methodology for CPU performance characterization was based on the abstract machine model. Benchmark programs are analyzed in another paper. A machine-independent model of program execution was developed to characterize both machine performance and program execution. By merging these machine and program characterizations, execution time can be estimated for arbitrary machine/program combinations. The work was continued into the domain of parallel and vector machines, including the issue of caches in vector processors and multiprocessors. All of the afore-mentioned accomplishments are more specifically summarized in this report, as well as those smaller in magnitude supported by this grant.

  4. Implementation of Benchmarking Transportation Logistics Practices and Future Benchmarking Organizations

    SciTech Connect

    Thrower, A.W.; Patric, J.; Keister, M.

    2008-07-01

    The purpose of the Office of Civilian Radioactive Waste Management's (OCRWM) Logistics Benchmarking Project is to identify established government and industry practices for the safe transportation of hazardous materials which can serve as a yardstick for design and operation of OCRWM's national transportation system for shipping spent nuclear fuel and high-level radioactive waste to the proposed repository at Yucca Mountain, Nevada. The project will present logistics and transportation practices and develop implementation recommendations for adaptation by the national transportation system. This paper will describe the process used to perform the initial benchmarking study, highlight interim findings, and explain how these findings are being implemented. It will also provide an overview of the next phase of benchmarking studies. The benchmarking effort will remain a high-priority activity throughout the planning and operational phases of the transportation system. The initial phase of the project focused on government transportation programs to identify those practices which are most clearly applicable to OCRWM. These Federal programs have decades of safe transportation experience, strive for excellence in operations, and implement effective stakeholder involvement, all of which parallel OCRWM's transportation mission and vision. The initial benchmarking project focused on four business processes that are critical to OCRWM's mission success, and can be incorporated into OCRWM planning and preparation in the near term. The processes examined were: transportation business model, contract management/out-sourcing, stakeholder relations, and contingency planning. More recently, OCRWM examined logistics operations of AREVA NC's Business Unit Logistics in France. The next phase of benchmarking will focus on integrated domestic and international commercial radioactive logistic operations. The prospective companies represent large scale shippers and have vast experience in safely and efficiently shipping spent nuclear fuel and other radioactive materials. Additional business processes may be examined in this phase. The findings of these benchmarking efforts will help determine the organizational structure and requirements of the national transportation system. (authors)

  5. Drill pipe protector development

    SciTech Connect

    Thomerson, C.; Kenne, R.; Wemple, R.P.

    1996-03-01

    The Geothermal Drilling Organization (GDO), formed in the early 1980s by the geothermal industry and the U.S. Department of Energy (DOE) Geothermal Division, sponsors specific development projects to advance the technologies used in geothermal exploration, drilling, and production phases. Individual GDO member companies can choose to participate in specific projects that are most beneficial to their industry segment. Sandia National Laboratories is the technical interface and contracting office for the DOE in these projects. Typical projects sponsored in the past have included a high temperature borehole televiewer, drill bits, muds/polymers, rotary head seals, and this project for drill pipe protectors. This report documents the development work of Regal International for high temperature geothermal pipe protectors.

  6. Coupling analysis of fluid-structure interaction in fluid-filled elbow pipe

    NASA Astrophysics Data System (ADS)

    Xu, W. W.; Wu, D. Z.; Wang, L. Q.

    2012-11-01

    Fluid in the ship pipeline, due to power equipment components (such as impellers, plungers, etc.) and valves, will induce turbulence, cavitations, which generate high-frequency vibration excitation lines. The measurements results show that fluid-induced vibration of the pipeline is not only confined to the pipeline, but also have an impact on the hull structure. Pipe vibration due to transient flow is very common in marine pipe system Thus fluid-structure interaction problems in shipping lines is being paid more and more attention. In this paper, the fluid-filled elbow pipe is simulated considering fluid-structure interaction (FSI) by the software ADINA. And the simulation results are validated through comparison with results obtained by other numerical solution. The results show that FSI affects the pipe-filled-water modal frequencies seriously, but have little effects on pipe vibration shapes, and the free vibration frequency of the fluid-filled pipe is lower than that of empty pipe. The pipe vibration amplitude and effective stress caused by fluid increase as the fluid velocity increase. Pipe continues vibrating after fluid velocity is steady, and the vibration is dispersing as time increase. The protection against vibration near the elbow is important because the maximum pipe deformation caused by fluid near the elbow. The maximum effective stress increases from 0 to 1.4MPa due to the fluid velocity increases from 0 to 20m/s in 5 seconds. So it is necessary to consider the FSI for fluid-filled pipe.

  7. Butterfly Project Report DARPA Parallel Architecture Benchmark Study

    E-print Network

    Scott, Michael L.

    Butterfly Project Report 13 DARPA Parallel Architecture Benchmark Study C. Brown, R. Fowler, T. Le on the Butterfly. The problems were Inspired by various capabilities in computer vision, and were proposed Butterfly Project Report 11 5. Hough Transformation Butterfly Project Report 10 6. Geometrical Constructions

  8. Pipe inspection using the pipe crawler. Innovative technology summary report

    SciTech Connect

    1999-05-01

    The US Department of Energy (DOE) continually seeks safer and more cost-effective remediation technologies for use in the decontamination and decommissioning (D and D) of nuclear facilities. In several of the buildings at the Fernald Site, there is piping that was used to transport process materials. As the demolition of these buildings occur, disposal of this piping has become a costly issue. Currently, all process piping is cut into ten-foot or less sections, the ends of the piping are wrapped and taped to prevent the release of any potential contaminants into the air, and the piping is placed in roll off boxes for eventual repackaging and shipment to the Nevada Test Site (NTS) for disposal. Alternatives that allow for the onsite disposal of process piping are greatly desired due to the potential for dramatic savings in current offsite disposal costs. No means is currently employed to allow for the adequate inspection of the interior of piping, and consequently, process piping has been assumed to be internally contaminated and thus routinely disposed of at NTS. The BTX-II system incorporates a high-resolution micro color camera with lightheads, cabling, a monitor, and a video recorder. The complete probe is capable of inspecting pipes with an internal diameter (ID) as small as 1.4 inches. By using readily interchangeable lightheads, the same system is capable of inspecting piping up to 24 inches in ID. The original development of the BTX system was for inspection of boiler tubes and small diameter pipes for build-up, pitting, and corrosion. However, the system is well suited for inspecting the interior of most types of piping and other small, confined areas. The report describes the technology, its performance, uses, cost, regulatory and policy issues, and lessons learned.

  9. Thirty years of fiberglass pipe in oilfield applications: A historical perspective

    SciTech Connect

    Oswald, K.J.

    1996-05-01

    A 30-year history of the use of fiberglass piping (FRP) systems for oil production piping is presented. Speculation about future uses of FRP in the oilfields is discussed. Problems encountered during the introduction of this type of pipe to the oilfields, and the evolution of early oilfield FRP systems is described. Improvements in FRP during the period of recent oilfield growth are reported. A representative list of significant uses of FRP in oilfield applications today is presented.

  10. Heat pipe technology: A bibliography with abstracts

    NASA Technical Reports Server (NTRS)

    1971-01-01

    The annual supplement on heat pipe technology for 1971 is presented. The document contains 101 references with abstracts and 47 patents. The subjects discussed are: (1) heat pipe applications, (2) heat pipe theory, (3) design, development, and fabrication of heat pipes, (4) testing and operation, (5) subject and author index, and (6) heat pipe related patents.

  11. Optimizing intermittent water supply in urban pipe distribution networks

    E-print Network

    Lieb, Anna M; Wilkening, Jon

    2015-01-01

    In many urban areas of the developing world, piped water is supplied only intermittently, as valves direct water to different parts of the water distribution system at different times. The flow is transient, and may transition between free-surface and pressurized, resulting in complex dynamical features with important consequences for water suppliers and users. Here, we develop a computational model of transition, transient pipe flow in a network, accounting for a wide variety of realistic boundary conditions. We validate the model against several published data sets, and demonstrate its use on a real pipe network. The model is extended to consider several optimization problems motivated by realistic scenarios. We demonstrate how to infer water flow in a small pipe network from a single pressure sensor, and show how to control water inflow to minimize damaging pressure gradients.

  12. Experimenting with a ``Pipe'' Whistle

    NASA Astrophysics Data System (ADS)

    Stafford, Olga

    2012-04-01

    A simple pipe whistle can be made using pieces of PVC pipe. The whistle can be used to measure the resonant frequencies of open or closed pipes. A slightly modified version of the device can be used to also investigate the interesting dependence of the sound frequencies produced on the orifice-to-edge distance. The pipe whistle described here allows students in a physics of music or introductory physics course to study an example of an "edge tone" device that produces discrete sound frequencies. From their textbooks, students likely know about standing waves produced by pipes or strings, as well as the resonant frequencies for open and closed pipes. To go a bit further, they can also learn how the frequency of the sound wave depends on the orifice-to-edge distance of the wind instrument.

  13. Closed-Loop Neuromorphic Benchmarks.

    PubMed

    Stewart, Terrence C; DeWolf, Travis; Kleinhans, Ashley; Eliasmith, Chris

    2015-01-01

    Evaluating the effectiveness and performance of neuromorphic hardware is difficult. It is even more difficult when the task of interest is a closed-loop task; that is, a task where the output from the neuromorphic hardware affects some environment, which then in turn affects the hardware's future input. However, closed-loop situations are one of the primary potential uses of neuromorphic hardware. To address this, we present a methodology for generating closed-loop benchmarks that makes use of a hybrid of real physical embodiment and a type of "minimal" simulation. Minimal simulation has been shown to lead to robust real-world performance, while still maintaining the practical advantages of simulation, such as making it easy for the same benchmark to be used by many researchers. This method is flexible enough to allow researchers to explicitly modify the benchmarks to identify specific task domains where particular hardware excels. To demonstrate the method, we present a set of novel benchmarks that focus on motor control for an arbitrary system with unknown external forces. Using these benchmarks, we show that an error-driven learning rule can consistently improve motor control performance across a randomly generated family of closed-loop simulations, even when there are up to 15 interacting joints to be controlled. PMID:26696820

  14. Closed-Loop Neuromorphic Benchmarks

    PubMed Central

    Stewart, Terrence C.; DeWolf, Travis; Kleinhans, Ashley; Eliasmith, Chris

    2015-01-01

    Evaluating the effectiveness and performance of neuromorphic hardware is difficult. It is even more difficult when the task of interest is a closed-loop task; that is, a task where the output from the neuromorphic hardware affects some environment, which then in turn affects the hardware's future input. However, closed-loop situations are one of the primary potential uses of neuromorphic hardware. To address this, we present a methodology for generating closed-loop benchmarks that makes use of a hybrid of real physical embodiment and a type of minimal simulation. Minimal simulation has been shown to lead to robust real-world performance, while still maintaining the practical advantages of simulation, such as making it easy for the same benchmark to be used by many researchers. This method is flexible enough to allow researchers to explicitly modify the benchmarks to identify specific task domains where particular hardware excels. To demonstrate the method, we present a set of novel benchmarks that focus on motor control for an arbitrary system with unknown external forces. Using these benchmarks, we show that an error-driven learning rule can consistently improve motor control performance across a randomly generated family of closed-loop simulations, even when there are up to 15 interacting joints to be controlled. PMID:26696820

  15. Flutter of articulated pipes at finite amplitude

    NASA Technical Reports Server (NTRS)

    Rousselet, J.; Herrmann, G.

    1977-01-01

    The plane motion of an articulated pipe made of two segments is examined and the flow velocity at which flutter manifests itself is sought. The pressure in the reservoir feeding the pipe is kept constant. In contrast to previous works, the flow velocity is not taken as a prescribed parameter of the system but is left to follow the laws of motion. This approach requires a nonlinear formulation of the problem and the equations of motion are solved using Krylov-Bogoliubov's method. A graph of the amplitude of the limit cycles, as a function of the fluid-system mass ratio, is presented and conclusions are drawn as to the necessity of considering nonlinearities in the analysis.

  16. Cryogenic Heat Pipe Experiment (CRYOHP)

    NASA Technical Reports Server (NTRS)

    Mcintosh, Roy

    1992-01-01

    The objective of the CRYOHP experiment is to conduct a shuttle experiment that demonstrates the reliable operation of two oxygen heat pipes in microgravity. The experiment will perform the following tasks: (1) demonstrate startup of the pipes from the supercritical state; (2) measure the heat transport capacity of the pipes; (3) measure evaporator and condenser film coefficients; and (4) work shuttle safety issues. The approach for the experiment is as follows: (1) fly two axially grooved oxygen heat pipes attached to mechanical stirling cycle tactical coolers; (2) integrate experiment in hitch-hiker canister; and (3) fly on shuttle and control from ground.

  17. Thermostructural applications of heat pipes

    NASA Technical Reports Server (NTRS)

    Peeples, M. E.; Reeder, J. C.; Sontag, K. E.

    1979-01-01

    The feasibility of integrating heat pipes in high temperature structure to reduce local hot spot temperature was evaluated for a variety of hypersonic aerospace vehicles. From an initial list of twenty-two potential applications, the single stage to orbit wing leading edge showed the greatest promise and was selected for preliminary design of an integrated heat pipe thermostructural system. The design consisted of a Hastelloy X assembly with sodium heat pipe passages aligned normal to the wing leading edge. A d-shaped heat pipe cross section was determined to be optimum from the standpoint of structural weight.

  18. Automatic Generation of Benchmarks for Plagiarism Detection Tools using Grammatical Evolution

    E-print Network

    Fernandez, Thomas

    Automatic Generation of Benchmarks for Plagiarism Detection Tools using Grammatical Evolution, Reliability Keywords: Source Code Plagiarism Detection Tool Assess- ment, Grammatical Evolution. 1. EXTENDED ABSTRACT Source code plagiarism detection is a mayor problem in universities worldwide. Although several

  19. Stiffness-Mass Ratios Method for a baseline determination and damage assessment of a benchmark structure

    E-print Network

    Rocha, Ramses Rodriguez

    2002-01-01

    A new method based on ratios between stiffness and mass values from the eigenvalue problem is introduced and applied to the benchmark structure to obtain baseline modal parameters utilizing damaged state information of the ...

  20. Randomized Benchmarking of Multiqubit Gates

    NASA Astrophysics Data System (ADS)

    Gaebler, J. P.; Meier, A. M.; Tan, T. R.; Bowler, R.; Lin, Y.; Hanneke, D.; Jost, J. D.; Home, J. P.; Knill, E.; Leibfried, D.; Wineland, D. J.

    2012-06-01

    We describe an extension of single-qubit gate randomized benchmarking that measures the error of multiqubit gates in a quantum information processor. This platform-independent protocol evaluates the performance of Clifford unitaries, which form a basis of fault-tolerant quantum computing. We implemented the benchmarking protocol with trapped ions and found an error per random two-qubit Clifford unitary of 0.1620.008, thus setting the first benchmark for such unitaries. By implementing a second set of sequences with an extra two-qubit phase gate inserted after each step, we extracted an error per phase gate of 0.0690.017. We conducted these experiments with transported, sympathetically cooled ions in a multizone Paul trapa system that can in principle be scaled to larger numbers of ions.

  1. Developing Financial Benchmarks for Critical Access Hospitals

    PubMed Central

    Pink, George H.; Holmes, George M.; Slifkin, Rebecca T.; Thompson, Roger E.

    2009-01-01

    This study developed and applied benchmarks for five indicators included in the CAH Financial Indicators Report, an annual, hospital-specific report distributed to all critical access hospitals (CAHs). An online survey of Chief Executive Officers and Chief Financial Officers was used to establish benchmarks. Indicator values for 2004, 2005, and 2006 were calculated for 421 CAHs and hospital performance was compared to the benchmarks. Although many hospitals performed better than benchmark on one indicator in 1 year, very few performed better than benchmark on all five indicators in all 3 years. The probability of performing better than benchmark differed among peer groups. PMID:19544935

  2. 49 CFR 195.114 - Used pipe.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 3 2011-10-01 2011-10-01 false Used pipe. 195.114 Section 195.114 Transportation...PIPELINE Design Requirements 195.114 Used pipe. Any used pipe installed in a pipeline system must comply with ...

  3. 49 CFR 195.114 - Used pipe.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 3 2010-10-01 2010-10-01 false Used pipe. 195.114 Section 195.114 Transportation...PIPELINE Design Requirements 195.114 Used pipe. Any used pipe installed in a pipeline system must comply with ...

  4. 46 CFR 197.336 - Pressure piping.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 2012-10-01 false Pressure piping. 197.336 Section...GENERAL PROVISIONS Commercial Diving Operations Equipment 197.336 Pressure piping. Piping systems...facility, carrying fluids under pressures exceeding 15 psig...

  5. 46 CFR 197.336 - Pressure piping.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 2010-10-01 false Pressure piping. 197.336 Section...GENERAL PROVISIONS Commercial Diving Operations Equipment 197.336 Pressure piping. Piping systems...facility, carrying fluids under pressures exceeding 15 psig...

  6. 46 CFR 197.336 - Pressure piping.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 2014-10-01 false Pressure piping. 197.336 Section...GENERAL PROVISIONS Commercial Diving Operations Equipment 197.336 Pressure piping. Piping systems...facility, carrying fluids under pressures exceeding 15 psig...

  7. 46 CFR 197.336 - Pressure piping.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 2011-10-01 false Pressure piping. 197.336 Section...GENERAL PROVISIONS Commercial Diving Operations Equipment 197.336 Pressure piping. Piping systems...facility, carrying fluids under pressures exceeding 15 psig...

  8. 46 CFR 197.336 - Pressure piping.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 2013-10-01 false Pressure piping. 197.336 Section...GENERAL PROVISIONS Commercial Diving Operations Equipment 197.336 Pressure piping. Piping systems...facility, carrying fluids under pressures exceeding 15 psig...

  9. 46 CFR 108.475 - Piping.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...of this chapter. (b) Each pipe, valve, and fitting made of...outside from corrosion. (c) Each pipe, valve, and fitting must have...the accumulation of dirt in its pipes; and (2) Drains to remove liquid from the...

  10. 46 CFR 108.475 - Piping.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...of this chapter. (b) Each pipe, valve, and fitting made of...outside from corrosion. (c) Each pipe, valve, and fitting must have...the accumulation of dirt in its pipes; and (2) Drains to remove liquid from the...

  11. 46 CFR 108.475 - Piping.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...of this chapter. (b) Each pipe, valve, and fitting made of...outside from corrosion. (c) Each pipe, valve, and fitting must have...the accumulation of dirt in its pipes; and (2) Drains to remove liquid from the...

  12. 46 CFR 108.475 - Piping.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...of this chapter. (b) Each pipe, valve, and fitting made of...outside from corrosion. (c) Each pipe, valve, and fitting must have...the accumulation of dirt in its pipes; and (2) Drains to remove liquid from the...

  13. 46 CFR 108.475 - Piping.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...of this chapter. (b) Each pipe, valve, and fitting made of...outside from corrosion. (c) Each pipe, valve, and fitting must have...the accumulation of dirt in its pipes; and (2) Drains to remove liquid from the...

  14. DOE Commercial Building Benchmark Models

    SciTech Connect

    Torcellini, P.; Deru, M.; Griffith, B.; Benne, K.; Halverson, M.; Winiarski, D.; Crawley, D.

    2008-01-01

    The excitement surrounding the drive to build and renovate commercial buildings to achieve exemplary and even 'net zero performance,' coupled with the realization that complex systems engineering is usually required to achieve such levels, has led to a broader use of computer energy simulations. To provide a consistent baseline of comparison and save time conducting such simulations, the U.S. Department of Energy (DOE) - through three of its national laboratories - has developed a set of standard benchmark building models for new and existing buildings. These models represent a complete revision of the DOE benchmark buildings originally developed in 2006. The shapes, thermal zoning, and operation of the models are more indicative of real buildings than in the previous versions. DOE has developed 15 benchmark buildings that represent most of the commercial building stock, across 16 locations (representing all U.S. climate zones) and with three vintages (new, pre-1980, and post-1980 construction). This paper will provide an executive summary overview of these benchmark buildings, and how they can save building analysts valuable time. Fully documented and implemented to use with the EnergyPlus energy simulation program, the benchmark models are publicly available and new versions will be created to maintain compatibility with new releases of EnergyPlus. The benchmark buildings will form the basis for research on specific building technologies, energy code development, appliance standards, and measurement of progress toward DOE energy goals. Having a common starting point allows us to better share and compare research results and move forward to make more energy efficient buildings.

  15. A Uranium Bioremediation Reactive Transport Benchmark

    SciTech Connect

    Yabusaki, Steven B.; Sengor, Sevinc; Fang, Yilin

    2015-06-01

    A reactive transport benchmark problem set has been developed based on in situ uranium bio-immobilization experiments that have been performed at a former uranium mill tailings site in Rifle, Colorado, USA. Acetate-amended groundwater stimulates indigenous microorganisms to catalyze the reduction of U(VI) to a sparingly soluble U(IV) mineral. The interplay between the flow, acetate loading periods and rates, microbially-mediated and geochemical reactions leads to dynamic behavior in metal- and sulfate-reducing bacteria, pH, alkalinity, and reactive mineral surfaces. The benchmark is based on an 8.5 m long one-dimensional model domain with constant saturated flow and uniform porosity. The 159-day simulation introduces acetate and bromide through the upgradient boundary in 14-day and 85-day pulses separated by a 10 day interruption. Acetate loading is tripled during the second pulse, which is followed by a 50 day recovery period. Terminal electron accepting processes for goethite, phyllosilicate Fe(III), U(VI), and sulfate are modeled using Monod-type rate laws. Major ion geochemistry modeled includes mineral reactions, as well as aqueous and surface complexation reactions for UO2++, Fe++, and H+. In addition to the dynamics imparted by the transport of the acetate pulses, U(VI) behavior involves the interplay between bioreduction, which is dependent on acetate availability, and speciation-controlled surface complexation, which is dependent on pH, alkalinity and available surface complexation sites. The general difficulty of this benchmark is the large number of reactions (74), multiple rate law formulations, a multisite uranium surface complexation model, and the strong interdependency and sensitivity of the reaction processes. Results are presented for three simulators: HYDROGEOCHEM, PHT3D, and PHREEQC.

  16. Ceramic heat pipe wick

    NASA Technical Reports Server (NTRS)

    Seidenberg, Benjamin (inventor); Swanson, Theodore (inventor)

    1989-01-01

    A wick for use in a capillary loop pump heat pipe is disclosed. The wick material is an essentially uniformly porous, permeable, open-cell, silicon dioxide/aluminum oxide inorganic ceramic foam having a silica fiber ratio, by weight, of about 78 to 22, respectively, a density of 6 lbs/cu ft, and an average pore size of less than 5 microns. A representative material having these characteristics is Lockheed Missile and Space Company, Inc.'s HTP 6-22. This material is fully compatible with the freons and anhydrous ammonia and allows for the use of these very efficient working fluids, and others, in capillary loops.

  17. Polymeric heat pipe wick

    NASA Technical Reports Server (NTRS)

    Seidenberg, Benjamin

    1988-01-01

    A wick for use in a capillary loop pump heat pipe is described. The wick material is an essentially uniformly porous, permeable, open-cell, polyethylene thermoplastic foam having an ultrahigh average molecular weight of from approximately 1 to 5 million, and an average pore size of about 10 to 12 microns. A representative material having these characteristics is POREX UF, which has an average molecular weight of about 3 million. This material is fully compatible with the FREONs and anhydrous ammonia and allows for the use of these very efficient working fluids in capillary loops.

  18. Computer program grade for design and analysis of graded-porosity heat-pipe wicks

    NASA Technical Reports Server (NTRS)

    Eninger, J. E.

    1974-01-01

    A computer program for numerical solution of differential equations that describe heat pipes with graded-porosity fibrous wicks is discussed. A mathematical problem is provided with a summary of the input and output steps used to solve it. The program is also applied to the analysis of a typical heat pipe.

  19. WATER QUALITY AND TREATMENT CONSIDERATIONS FOR CEMENT-LINED AND A-C PIPE

    EPA Science Inventory

    Both cement mortar lined (CML) and asbestos-cement pipes (A-C) are widely used in many water systems. Cement linings are also commonly applied in-situ after pipe cleaning, usually to prevent the recurrence of red water or tuberculation problems. Unfortunately, little consideratio...

  20. Effects of Stormwater Pipe Size and Rainfall on Sediment and Nutrients Delivered to a Coastal Bayou

    EPA Science Inventory

    Pollutants discharged from stormwater pipes can cause water quality and ecosystem problems in coastal bayous. A study was conducted to characterize sediment and nutrients discharged by small and large (, 20 cm and .20 cm in internal diameters, respectively) pipes under different ...

  1. Internal erosion during soil pipe flow: Role in gully erosion and hillslope instability

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many field observations have lead to speculation on the role of piping in embankment failures, landslides, and gully erosion. However, there has not been a consensus on the subsurface flow and erosion processes involved and inconsistent use of terms have exasperated the problem. One such piping proc...

  2. Building a Copper Pipe "Xylophone."

    ERIC Educational Resources Information Center

    Lapp, David R.

    2003-01-01

    Explains how to use the equation for frequency of vibration of a transversely oscillating bar or pipe with both ends free to vibrate to build a simple and inexpensive xylophone from a 3-meter section of copper pipe. The instrument produces a full major scale and can be used to investigate various musical intervals. (Author/NB)

  3. Demonstrating Sound Impulses in Pipes.

    ERIC Educational Resources Information Center

    Raymer, M. G.; Micklavzina, Stan

    1995-01-01

    Describes a simple, direct method to demonstrate the effects of the boundary conditions on sound impulse reflections in pipes. A graphical display of the results can be made using a pipe, cork, small hammer, microphone, and fast recording electronics. Explains the principles involved. (LZ)

  4. Heat Pipe Blocks Return Flow

    NASA Technical Reports Server (NTRS)

    Eninger, J. E.

    1982-01-01

    Metal-foil reed valve in conventional slab-wick heat pipe limits heat flow to one direction only. With sink warmer than source, reed is forced closed and fluid returns to source side through annular transfer wick. When this occurs, wick slab on sink side of valve dries out and heat pipe ceases to conduct heat.

  5. Alternate high capacity heat pipe

    NASA Technical Reports Server (NTRS)

    Voss, F. E.

    1986-01-01

    The performance predictions for a fifty foot heat pipe (4 foot evaporator - 46 foot condensor) are discussed. These performance predictions are supported by experimental data for a four foot heat pipe. Both heat pipes have evaporators with axial groove wick structures and condensers with powder metal external artery wick structures. The predicted performance of a rectangular axial groove/external artery heat pipe operating in space is given. Heat transport versus groove width is plotted for 100, 200 and 300 grooves in the evaporator. The curves show that maximum power is achieved for groove widths from 0.040 to 0.053 as the number of grooves varies from 300 to 100. The corresponding range of maximum power is 3150 to 2400 watts. The relationships between groove width and heat pipe evaporate diameter for 100, 200 and 300 grooves in the evaporator are given. A four foot heat pipe having a three foot condenser and one foot evaporator was built and tested. The evaporator wick structure used axial grooves with rectangular cross sections, and the condenser wick structure used powder metal with an external artery configuration. Fabrication drawings are enclosed. The predicted and measured performance for this heat pipe is shown. The agreement between predicted and measured performance is good and therefore substantiates the predicted performance for a fifty foot heat pipe.

  6. Pipe crawler with stabilizing midsection

    DOEpatents

    Zollinger, William T. (Martinez, GA); Treanor, Richard C. (Augusta, GA)

    1994-01-01

    A pipe crawler having a midsection that provides the stability and flexibty to allow the pipe crawler to negotiate curved and uneven segments of piping while traveling through piping systems. The pipe crawler comprises a front leg assembly, a rear leg assembly, a midsection with a gimbal at each end for connecting the midsection to the front and rear leg assemblies in a flexible manner, and an air cylinder for changing the distance between the front and rear leg assemblies. The pipe crawler moves in "inch worm" fashion with the front and rear leg assemblies alternating between an extended and a retracted position as the air cylinder moves the retracted leg assembly forward. The midsection has a plurality of legs extending radially for holding the midsection within a maximum displacement from the piping axis so that the gimbals are not pivoted to extreme angles where they might lock up or seize. When the midsection is displaced sufficiently, its legs with wheels on each end engage the interior surface of the piping and prevent further displacement. Using two gimbals divides the angle between the planes defined by the front and rear leg assemblies which also helps to prevent excessive gimbal pivoting.

  7. Pipe crawler with stabilizing midsection

    DOEpatents

    Zollinger, W.T.; Treanor, R.C.

    1994-12-27

    A pipe crawler is described having a midsection that provides the stability and flexibility to allow the pipe crawler to negotiate curved and uneven segments of piping while traveling through piping systems. The pipe crawler comprises a front leg assembly, a rear leg assembly, a midsection with a gimbal at each end for connecting the midsection to the front and rear leg assemblies in a flexible manner, and an air cylinder for changing the distance between the front and rear leg assemblies. The pipe crawler moves in ''inch worm'' fashion with the front and rear leg assemblies alternating between an extended and a retracted position as the air cylinder moves the retracted leg assembly forward. The midsection has a plurality of legs extending radially for holding the midsection within a maximum displacement from the piping axis so that the gimbals are not pivoted to extreme angles where they might lock up or seize. When the midsection is displaced sufficiently, its legs with wheels on each end engage the interior surface of the piping and prevent further displacement. Using two gimbals divides the angle between the planes defined by the front and rear leg assemblies which also helps to prevent excessive gimbal pivoting. 5 figures.

  8. Fracture mechanics models developed for piping reliability assessment in light water reactors: piping reliability project

    SciTech Connect

    Harris, D.O.; Lim, E.Y.; Dedhia, D.D.; Woo, H.H.; Chou, C.K.

    1982-06-01

    The efforts concentrated on modifications of the stratified Monte Carlo code called PRAISE (Piping Reliability Analysis Including Seismic Events) to make it more widely applicable to probabilistic fracture mechanics analysis of nuclear reactor piping. Pipe failures are considered to occur as the result of crack-like defects introduced during fabrication, that escape detection during inspections. The code modifications allow the following factors in addition to those considered in earlier work to be treated: other materials, failure criteria and subcritical crack growth characteristic; welding residual and vibratory stresses; and longitudinal welds (the original version considered only circumferential welds). The fracture mechanics background for the code modifications is included, and details of the modifications themselves provided. Additionally, an updated version of the PRAISE user's manual is included. The revised code, known as PRAISE-B was then applied to a variety of piping problems, including various size lines subject to stress corrosion cracking and vibratory stresses. Analyses including residual stresses and longitudinal welds were also performed.

  9. An investigation of corrosion in liquid-metal heat pipes

    SciTech Connect

    Adkins, D.R.; Rawlinson, K.S.; Andraka, C.E.; Showalter, S.K.; Moreno, J.B.; Moss, T.A.; Cordiero, P.G.

    1998-08-01

    Research is underway to develop a 75-kW heat pipe to transfer solar energy from the focus of a parabolic dish concentrator to the heater tubes of a Stirling engine. The high flux levels and high total power level encountered in this application have made it necessary to use a high-performance wick structure with fibers on the order of 4 to 8 microns in diameter. This fine wick structure is highly susceptible to corrosion damage and plugging, as dissolved contaminants plate out on the evaporator surface. Normal operation of the heat pipe also tends to concentrate contaminants in localized areas of the evaporator surface where heat fluxes are the highest. Sandia National Laboratories is conducting a systematic study to identify procedures that reduce corrosion and contamination problems in liquid-metal heat pipes. A series of heat pipes are being tested to explore different options for cleaning heat-pipe systems. Models are being developed to help understand the overall importance of operating parameters on the life of heat-pipe systems. In this paper, the authors present their efforts to reduce corrosion damage.

  10. Monitoring pipe line stress due to ground displacement

    SciTech Connect

    Greenwood, J.H. Jr.

    1986-04-01

    Northwest Pipeline Corp. has a large-diameter natural gas pipe line system from Ignacio, Colo., to Sumas, Wash. At Douglas Pass in Colorado, large landslides required several sections of the line to be relocated outside the slide areas: 4,400 ft of new line in April 1962 and 3,200 ft in March 1963. No serious disruptions occurred for the next 16 years. Then in July 1979, some 1,200 ft had to be relocated. From 1980 to date, many landslides in the Douglas Pass area have caused new deformations, with the springs of 1983 and 1984 being the worst years. In 1980, Northwest Pipeline began engineering and geotechnical studies of the landslide problems. These led to instrumentation and pipe monitoring which indicated that pipe failure can be predicted and prevented if important slope deformations or increases in pipe stresses are detected early enough to implement some mitigating measures. Excavation of the pipe to relieve the stresses was used in most cases. The method was so successful that no pipe failure occurred in 1984 within instrumented sections, in spite of the exceptionally bad climatic conditions experienced.

  11. Vapor spill pipe monitor

    DOEpatents

    Bianchini, G.M.; McRae, T.G.

    1983-06-23

    The invention is a method and apparatus for continually monitoring the composition of liquefied natural gas flowing from a spill pipe during a spill test by continually removing a sample of the LNG by means of a probe, gasifying the LNG in the probe, and sending the vaporized LNG to a remote ir gas detector for analysis. The probe comprises three spaced concentric tubes surrounded by a water jacket which communicates with a flow channel defined between the inner and middle, and middle and outer tubes. The inner tube is connected to a pump for providing suction, and the probe is positioned in the LNG flow below the spill pipe with the tip oriented partly downward so that LNG is continuously drawn into the inner tube through a small orifice. The probe is made of a high thermal conductivity metal. Hot water is flowed through the water jacket and through the flow channel between the three tubes to provide the necessary heat transfer to flash vaporize the LNG passing through the inner channel of the probe. The gasified LNG is transported through a connected hose or tubing extending from the probe to a remote ir sensor which measures the gas composition.

  12. Thirty years of fiberglass pipe in oilfield applications: A historical perspective

    SciTech Connect

    Oswald, K.J.

    1995-10-01

    Oilfield piping must handle mixtures containing many fluids which are highly corrosive to metals. Salt water, sour crude, hydrogen sulfide and carbon dioxide are only a few of the corrosives which are handled continuously on a large scale in oilfields throughout the world. This paper presents a 30 year history of the use of fiberglass piping systems to manage corrosion problems in oil production piping, and speculates about future uses of fiberglass piping in the oilfields. A description of the problems encountered during the introduction of this type of pipe to the oilfields is given, and the evolution of early oilfield fiberglass piping systems is described. Improvements in fiberglass piping during the period of recent oilfield growth are reported, and the contributions of fiberglass pipe in the field of corrosion control during this period of growth are discussed. A representative list of significant uses of fiberglass pipe in oilfield applications today is presented, predictions about the future of fiberglass tubular products in oilfield corrosion applications are made.

  13. Simple mathematical law benchmarks human confrontations.

    PubMed

    Johnson, Neil F; Medina, Pablo; Zhao, Guannan; Messinger, Daniel S; Horgan, John; Gill, Paul; Bohorquez, Juan Camilo; Mattson, Whitney; Gangi, Devon; Qi, Hong; Manrique, Pedro; Velasquez, Nicolas; Morgenstern, Ana; Restrepo, Elvira; Johnson, Nicholas; Spagat, Michael; Zarama, Roberto

    2013-01-01

    Many high-profile societal problems involve an individual or group repeatedly attacking another - from child-parent disputes, sexual violence against women, civil unrest, violent conflicts and acts of terror, to current cyber-attacks on national infrastructure and ultrafast cyber-trades attacking stockholders. There is an urgent need to quantify the likely severity and timing of such future acts, shed light on likely perpetrators, and identify intervention strategies. Here we present a combined analysis of multiple datasets across all these domains which account for >100,000 events, and show that a simple mathematical law can benchmark them all. We derive this benchmark and interpret it, using a minimal mechanistic model grounded by state-of-the-art fieldwork. Our findings provide quantitative predictions concerning future attacks; a tool to help detect common perpetrators and abnormal behaviors; insight into the trajectory of a 'lone wolf'; identification of a critical threshold for spreading a message or idea among perpetrators; an intervention strategy to erode the most lethal clusters; and more broadly, a quantitative starting point for cross-disciplinary theorizing about human aggression at the individual and group level, in both real and online worlds. PMID:24322528

  14. Simple mathematical law benchmarks human confrontations

    NASA Astrophysics Data System (ADS)

    Johnson, Neil F.; Medina, Pablo; Zhao, Guannan; Messinger, Daniel S.; Horgan, John; Gill, Paul; Bohorquez, Juan Camilo; Mattson, Whitney; Gangi, Devon; Qi, Hong; Manrique, Pedro; Velasquez, Nicolas; Morgenstern, Ana; Restrepo, Elvira; Johnson, Nicholas; Spagat, Michael; Zarama, Roberto

    2013-12-01

    Many high-profile societal problems involve an individual or group repeatedly attacking another - from child-parent disputes, sexual violence against women, civil unrest, violent conflicts and acts of terror, to current cyber-attacks on national infrastructure and ultrafast cyber-trades attacking stockholders. There is an urgent need to quantify the likely severity and timing of such future acts, shed light on likely perpetrators, and identify intervention strategies. Here we present a combined analysis of multiple datasets across all these domains which account for >100,000 events, and show that a simple mathematical law can benchmark them all. We derive this benchmark and interpret it, using a minimal mechanistic model grounded by state-of-the-art fieldwork. Our findings provide quantitative predictions concerning future attacks; a tool to help detect common perpetrators and abnormal behaviors; insight into the trajectory of a `lone wolf' identification of a critical threshold for spreading a message or idea among perpetrators; an intervention strategy to erode the most lethal clusters; and more broadly, a quantitative starting point for cross-disciplinary theorizing about human aggression at the individual and group level, in both real and online worlds.

  15. Simple mathematical law benchmarks human confrontations

    PubMed Central

    Johnson, Neil F.; Medina, Pablo; Zhao, Guannan; Messinger, Daniel S.; Horgan, John; Gill, Paul; Bohorquez, Juan Camilo; Mattson, Whitney; Gangi, Devon; Qi, Hong; Manrique, Pedro; Velasquez, Nicolas; Morgenstern, Ana; Restrepo, Elvira; Johnson, Nicholas; Spagat, Michael; Zarama, Roberto

    2013-01-01

    Many high-profile societal problems involve an individual or group repeatedly attacking another from child-parent disputes, sexual violence against women, civil unrest, violent conflicts and acts of terror, to current cyber-attacks on national infrastructure and ultrafast cyber-trades attacking stockholders. There is an urgent need to quantify the likely severity and timing of such future acts, shed light on likely perpetrators, and identify intervention strategies. Here we present a combined analysis of multiple datasets across all these domains which account for >100,000 events, and show that a simple mathematical law can benchmark them all. We derive this benchmark and interpret it, using a minimal mechanistic model grounded by state-of-the-art fieldwork. Our findings provide quantitative predictions concerning future attacks; a tool to help detect common perpetrators and abnormal behaviors; insight into the trajectory of a lone wolf'; identification of a critical threshold for spreading a message or idea among perpetrators; an intervention strategy to erode the most lethal clusters; and more broadly, a quantitative starting point for cross-disciplinary theorizing about human aggression at the individual and group level, in both real and online worlds. PMID:24322528

  16. PyMPI Dynamic Benchmark

    Energy Science and Technology Software Center (ESTSC)

    2007-02-16

    Pynamic is a benchmark designed to test a system's ability to handle the Dynamic Linking and Loading (DLL) requirements of Python-based scientific applications. This benchmark is developed to add a workload to our testing environment, a workload that represents a newly emerging class of DLL behaviors. Pynamic buildins on pyMPI, and MPI extension to Python C-extension dummy codes and a glue layer that facilitates linking and loading of the generated dynamic modules into the resultingmorepyMPI. Pynamic is configurable, enabling modeling the static properties of a specific code as described in section 5. It does not, however, model any significant computationss of the target and hence, it is not subjected to the same level of control as the target code. In fact, HPC computer vendors and tool developers will be encouraged to add it to their tesitn suite once the code release is completed. an ability to produce and run this benchmark is an effective test for valifating the capability of a compiler and linker/loader as well as an OS kernel and other runtime system of HPC computer vendors. In addition, the benchmark is designed as a test case for stressing code development tools. Though Python has recently gained popularity in the HPC community, it heavy DLL operations have hindered certain HPC code development tools, notably parallel debuggers, from performing optimally.less

  17. Science Grades K-4 Benchmarks.

    ERIC Educational Resources Information Center

    Arkansas State Dept. of Education, Little Rock.

    This document explains the Arkansas science benchmarks for grades K-4 which were developed to provide guidance to science teachers. The content standards for three strands--physical science systems, life science systems, and Earth science/space science systems--were identified based on grade levels. (YDS)

  18. Austin Community College Benchmarking Update.

    ERIC Educational Resources Information Center

    Austin Community Coll., TX. Office of Institutional Effectiveness.

    Austin Community College contracted with MGT of America, Inc. in spring 1999 to develop a peer and benchmark (best) practices analysis on key indicators. These indicators were updated in spring 2002 using data from eight Texas community colleges and four non-Texas institutions that represent large, comprehensive, urban community colleges, similar

  19. A comparison of five benchmarks

    NASA Technical Reports Server (NTRS)

    Huss, Janice E.; Pennline, James A.

    1987-01-01

    Five benchmark programs were obtained and run on the NASA Lewis CRAY X-MP/24. A comparison was made between the programs codes and between the methods for calculating performance figures. Several multitasking jobs were run to gain experience in how parallel performance is measured.

  20. Benchmarks for industrial energy efficiency

    SciTech Connect

    Amarnath, K.R.; Kumana, J.D.; Shah, J.V.

    1996-12-31

    What are the standards for improving energy efficiency for industries such as petroleum refining, chemicals, and glass manufacture? How can different industries in emerging markets and developing accelerate the pace of improvements? This paper discusses several case studies and experiences relating to this subject emphasizing the use of energy efficiency benchmarks. Two important benchmarks are discussed. The first is based on a track record of outstanding performers in the related industry segment; the second benchmark is based on site specific factors. Using energy use reduction targets or benchmarks, projects have been implemented in Mexico, Poland, India, Venezuela, Brazil, China, Thailand, Malaysia, Republic of South Africa and Russia. Improvements identified through these projects include a variety of recommendations. The use of oxy-fuel and electric furnaces in the glass industry in Poland; reconfiguration of process heat recovery systems for refineries in China, Malaysia, and Russia; recycling and reuse of process wastewater in Republic of South Africa; cogeneration plant in Venezuela. The paper will discuss three case studies of efforts undertaken in emerging market countries to improve energy efficiency.

  1. Promethus Hot Leg Piping Concept

    SciTech Connect

    AM Girbik; PA Dilorenzo

    2006-01-24

    The Naval Reactors Prime Contractor Team (NRPCT) recommended the development of a gas cooled reactor directly coupled to a Brayton energy conversion system as the Space Nuclear Power Plant (SNPP) for NASA's Project Prometheus. The section of piping between the reactor outlet and turbine inlet, designated as the hot leg piping, required unique design features to allow the use of a nickel superalloy rather than a refractory metal as the pressure boundary. The NRPCT evaluated a variety of hot leg piping concepts for performance relative to SNPP system parameters, manufacturability, material considerations, and comparison to past high temperature gas reactor (HTGR) practice. Manufacturability challenges and the impact of pressure drop and turbine entrance temperature reduction on cycle efficiency were discriminators between the piping concepts. This paper summarizes the NRPCT hot leg piping evaluation, presents the concept recommended, and summarizes developmental issues for the recommended concept.

  2. Flexible ultrasonic pipe inspection apparatus

    DOEpatents

    Jenkins, Charles F. (Aiken, SC); Howard, Boyd D. (Augusta, GA)

    1998-01-01

    A flexible, modular ultrasonic pipe inspection apparatus, comprising a flexible, hollow shaft that carries a plurality of modules, including at least one rotatable ultrasonic transducer, a motor/gear unit, and a position/signal encoder. The modules are connected by flexible knuckle joints that allow each module of the apparatus to change its relative orientation with respect to a neighboring module, while the shaft protects electrical wiring from kinking or buckling while the apparatus moves around a tight corner. The apparatus is moved through a pipe by any suitable means, including a tether or drawstring attached to the nose or tail, differential hydraulic pressure, or a pipe pig. The rotational speed of the ultrasonic transducer and the forward velocity of the apparatus are coordinated so that the beam sweeps out the entire interior surface of the pipe, enabling the operator to accurately assess the condition of the pipe wall and determine whether or not leak-prone corrosion damage is present.

  3. Prometheus Hot Leg Piping Concept

    SciTech Connect

    Gribik, Anastasia M.; DiLorenzo, Peter A.

    2007-01-30

    The Naval Reactors Prime Contractor Team (NRPCT) recommended the development of a gas cooled reactor directly coupled to a Brayton energy conversion system as the Space Nuclear Power Plant (SNPP) for NASA's Project Prometheus. The section of piping between the reactor outlet and turbine inlet, designated as the hot leg piping, required unique design features to allow the use of a nickel superalloy rather than a refractory metal as the pressure boundary. The NRPCT evaluated a variety of hot leg piping concepts for performance relative to SNPP system parameters, manufacturability, material considerations, and comparison to past high temperature gas reactor (HTGR) practice. Manufacturability challenges and the impact of pressure drop and turbine entrance temperature reduction on cycle efficiency were discriminators between the piping concepts. This paper summarizes the NRPCT hot leg piping evaluation, presents the concept recommended, and summarizes developmental issues for the recommended concept.

  4. Verification Benchmarks to Assess the Implementation of Computational Fluid Dynamics Based Hemolysis Prediction Models.

    PubMed

    Hariharan, Prasanna; D'Souza, Gavin; Horner, Marc; Malinauskas, Richard A; Myers, Matthew R

    2015-09-01

    As part of an ongoing effort to develop verification and validation (V&V) standards for using computational fluid dynamics (CFD) in the evaluation of medical devices, we have developed idealized flow-based verification benchmarks to assess the implementation of commonly cited power-law based hemolysis models in CFD. Verification process ensures that all governing equations are solved correctly and the model is free of user and numerical errors. To perform verification for power-law based hemolysis modeling, analytical solutions for the Eulerian power-law blood damage model (which estimates hemolysis index (HI) as a function of shear stress and exposure time) were obtained for Couette and inclined Couette flow models, and for Newtonian and non-Newtonian pipe flow models. Subsequently, CFD simulations of fluid flow and HI were performed using Eulerian and three different Lagrangian-based hemolysis models and compared with the analytical solutions. For all the geometries, the blood damage results from the Eulerian-based CFD simulations matched the Eulerian analytical solutions within ?1%, which indicates successful implementation of the Eulerian hemolysis model. Agreement between the Lagrangian and Eulerian models depended upon the choice of the hemolysis power-law constants. For the commonly used values of power-law constants (? ?=?1.9-2.42 and ? ?=?0.65-0.80), in the absence of flow acceleration, most of the Lagrangian models matched the Eulerian results within 5%. In the presence of flow acceleration (inclined Couette flow), moderate differences (?10%) were observed between the Lagrangian and Eulerian models. This difference increased to greater than 100% as the beta exponent decreased. These simplified flow problems can be used as standard benchmarks for verifying the implementation of blood damage predictive models in commercial and open-source CFD codes. The current study only used power-law model as an illustrative example to emphasize the need for model verification. Similar verification problems could be developed for other types of hemolysis models (such as strain-based and energy dissipation-based methods). However, since the current study did not include experimental validation, the results from the verified models do not guarantee accurate hemolysis predictions. This verification step must be followed by experimental validation before the hemolysis models can be used for actual device safety evaluations. PMID:26065371

  5. Benchmarking Gas Path Diagnostic Methods: A Public Approach

    NASA Technical Reports Server (NTRS)

    Simon, Donald L.; Bird, Jeff; Davison, Craig; Volponi, Al; Iverson, R. Eugene

    2008-01-01

    Recent technology reviews have identified the need for objective assessments of engine health management (EHM) technology. The need is two-fold: technology developers require relevant data and problems to design and validate new algorithms and techniques while engine system integrators and operators need practical tools to direct development and then evaluate the effectiveness of proposed solutions. This paper presents a publicly available gas path diagnostic benchmark problem that has been developed by the Propulsion and Power Systems Panel of The Technical Cooperation Program (TTCP) to help address these needs. The problem is coded in MATLAB (The MathWorks, Inc.) and coupled with a non-linear turbofan engine simulation to produce "snap-shot" measurements, with relevant noise levels, as if collected from a fleet of engines over their lifetime of use. Each engine within the fleet will experience unique operating and deterioration profiles, and may encounter randomly occurring relevant gas path faults including sensor, actuator and component faults. The challenge to the EHM community is to develop gas path diagnostic algorithms to reliably perform fault detection and isolation. An example solution to the benchmark problem is provided along with associated evaluation metrics. A plan is presented to disseminate this benchmark problem to the engine health management technical community and invite technology solutions.

  6. Technology for concrete pipe manipulator

    NASA Astrophysics Data System (ADS)

    Li, Bin; Wang, Dan; Lin, Renzhi

    2010-01-01

    The pipe manipulator is a developing mechatronic system to enhance productivity and protects workers from cave-ins in the trench while excavating and laying pipe. The pipe manipulator is for installing concrete pipe into the trench. It is an optical-electro-mechanical system. The mechanism is make up of two parts, the upside and underside. The upside is for lifting the equipment by backhoe and rotating the underside mechanism. It includes rigidity lift beams, holding pad, four-bar linkages, hydraulic cylinder, rotating support, and rotating mechanism. Holding pad will press the bucket back to keep the bucket hooking the pipe man safely and stably. The underside mechanism is for lifting, holding and adjusting the pipe section's stance. The underside mechanism includes support trolley, and lift fork. The support trolley is driven by hydraulic cylinder for moving the fork forward or backward while laying a pipe into trench. The fork is with a self-lock mechanism for preventing the pipe from slide out of the prongs. A new photoelectric locating system is developed for auto-measuring the installing pipe section's stance within the work area. The laser target has been developed as a key part in the photoelectric locating systems. The photoelectric target is a rotating polar coordinate. Photodiodes are used for making the polar radius. There is an angular displacement sensor sitting on the heart-axis of the target for measuring angle of the target rotating. The pipe manipulator can be located by the system, and the locating methods have been presented at last of the paper.

  7. Technology for concrete pipe manipulator

    NASA Astrophysics Data System (ADS)

    Li, Bin; Wang, Dan; Lin, Renzhi

    2009-12-01

    The pipe manipulator is a developing mechatronic system to enhance productivity and protects workers from cave-ins in the trench while excavating and laying pipe. The pipe manipulator is for installing concrete pipe into the trench. It is an optical-electro-mechanical system. The mechanism is make up of two parts, the upside and underside. The upside is for lifting the equipment by backhoe and rotating the underside mechanism. It includes rigidity lift beams, holding pad, four-bar linkages, hydraulic cylinder, rotating support, and rotating mechanism. Holding pad will press the bucket back to keep the bucket hooking the pipe man safely and stably. The underside mechanism is for lifting, holding and adjusting the pipe section's stance. The underside mechanism includes support trolley, and lift fork. The support trolley is driven by hydraulic cylinder for moving the fork forward or backward while laying a pipe into trench. The fork is with a self-lock mechanism for preventing the pipe from slide out of the prongs. A new photoelectric locating system is developed for auto-measuring the installing pipe section's stance within the work area. The laser target has been developed as a key part in the photoelectric locating systems. The photoelectric target is a rotating polar coordinate. Photodiodes are used for making the polar radius. There is an angular displacement sensor sitting on the heart-axis of the target for measuring angle of the target rotating. The pipe manipulator can be located by the system, and the locating methods have been presented at last of the paper.

  8. Course Title Credits Critical Benchmark(s) Strongly Recommended AGRI 192 Orientation to Agricultural Systems 1

    E-print Network

    Beveridge, Ross

    Course Title Credits Critical Benchmark(s) Strongly Recommended AGRI 192 Orientation to Agricultural Systems 1 or AGRI 292 Transfer Orientation 1 AREC 202 Agricultural and Resource Economics (AUCC 3C Critical Benchmark(s) Strongly Recommended ANEQ 101 Food Animal Science 4 ANEQ 102 (F) Introduction

  9. Course Title Credits Critical Benchmark(s) Strongly Recommended AGRI 192 Orientation to Agricultural Systems 1

    E-print Network

    Beveridge, Ross

    Course Title Credits Critical Benchmark(s) Strongly Recommended AGRI 192 Orientation to Agricultural Systems 1 or AGRI 292 Transfer Orientation 1 CHEM 107 Fundamentals of Chemistry (AUCC 3A) 4 CHEM Credits Critical Benchmark(s) Strongly Recommended FSHN 125 Food and Nutrition in Health 2 or FSHN 150

  10. Protein Models Docking Benchmark 2

    PubMed Central

    Anishchenko, Ivan; Kundrotas, Petras J.; Tuzikov, Alexander V.; Vakser, Ilya A.

    2015-01-01

    Structural characterization of protein-protein interactions is essential for our ability to understand life processes. However, only a fraction of known proteins have experimentally determined structures. Such structures provide templates for modeling of a large part of the proteome, where individual proteins can be docked by template-free or template-based techniques. Still, the sensitivity of the docking methods to the inherent inaccuracies of protein models, as opposed to the experimentally determined high-resolution structures, remains largely untested, primarily due to the absence of appropriate benchmark set(s). Structures in such a set should have pre-defined inaccuracy levels and, at the same time, resemble actual protein models in terms of structural motifs/packing. The set should also be large enough to ensure statistical reliability of the benchmarking results. We present a major update of the previously developed benchmark set of protein models. For each interactor, six models were generated with the model-to-native C? RMSD in the 1 to 6 range. The models in the set were generated by a new approach, which corresponds to the actual modeling of new protein structures in the real case scenario, as opposed to the previous set, where a significant number of structures were model-like only. In addition, the larger number of complexes (165 vs. 63 in the previous set) increases the statistical reliability of the benchmarking. We estimated the highest accuracy of the predicted complexes (according to CAPRI criteria), which can be attained using the benchmark structures. The set is available at http://dockground.bioinformatics.ku.edu. PMID:25712716

  11. Protein models docking benchmark 2.

    PubMed

    Anishchenko, Ivan; Kundrotas, Petras J; Tuzikov, Alexander V; Vakser, Ilya A

    2015-05-01

    Structural characterization of protein-protein interactions is essential for our ability to understand life processes. However, only a fraction of known proteins have experimentally determined structures. Such structures provide templates for modeling of a large part of the proteome, where individual proteins can be docked by template-free or template-based techniques. Still, the sensitivity of the docking methods to the inherent inaccuracies of protein models, as opposed to the experimentally determined high-resolution structures, remains largely untested, primarily due to the absence of appropriate benchmark set(s). Structures in such a set should have predefined inaccuracy levels and, at the same time, resemble actual protein models in terms of structural motifs/packing. The set should also be large enough to ensure statistical reliability of the benchmarking results. We present a major update of the previously developed benchmark set of protein models. For each interactor, six models were generated with the model-to-native C(?) RMSD in the 1 to 6 range. The models in the set were generated by a new approach, which corresponds to the actual modeling of new protein structures in the "real case scenario," as opposed to the previous set, where a significant number of structures were model-like only. In addition, the larger number of complexes (165 vs. 63 in the previous set) increases the statistical reliability of the benchmarking. We estimated the highest accuracy of the predicted complexes (according to CAPRI criteria), which can be attained using the benchmark structures. The set is available at http://dockground.bioinformatics.ku.edu. PMID:25712716

  12. Confidential Benchmarking based on Multiparty Computation

    E-print Network

    International Association for Cryptologic Research (IACR)

    with too much debt. We propose a model based on linear programming for doing the benchmarking and implement devel- oped this confidential benchmarking system that uses linear programming to compute benchmark market. So on the one hand, a number of banks have too many farmers with potential losses as customers

  13. NAS Parallel Benchmark Results 11-96. 1.0

    NASA Technical Reports Server (NTRS)

    Bailey, David H.; Bailey, David; Chancellor, Marisa K. (Technical Monitor)

    1997-01-01

    The NAS Parallel Benchmarks have been developed at NASA Ames Research Center to study the performance of parallel supercomputers. The eight benchmark problems are specified in a "pencil and paper" fashion. In other words, the complete details of the problem to be solved are given in a technical document, and except for a few restrictions, benchmarkers are free to select the language constructs and implementation techniques best suited for a particular system. These results represent the best results that have been reported to us by the vendors for the specific 3 systems listed. In this report, we present new NPB (Version 1.0) performance results for the following systems: DEC Alpha Server 8400 5/440, Fujitsu VPP Series (VX, VPP300, and VPP700), HP/Convex Exemplar SPP2000, IBM RS/6000 SP P2SC node (120 MHz), NEC SX-4/32, SGI/CRAY T3E, SGI Origin200, and SGI Origin2000. We also report High Performance Fortran (HPF) based NPB results for IBM SP2 Wide Nodes, HP/Convex Exemplar SPP2000, and SGI/CRAY T3D. These results have been submitted by Applied Parallel Research (APR) and Portland Group Inc. (PGI). We also present sustained performance per dollar for Class B LU, SP and BT benchmarks.

  14. NRC-BNL BENCHMARK PROGRAM ON EVALUATION OF METHODS FOR SEISMIC ANALYSIS OF COUPLED SYSTEMS.

    SciTech Connect

    XU,J.

    1999-08-15

    A NRC-BNL benchmark program for evaluation of state-of-the-art analysis methods and computer programs for seismic analysis of coupled structures with non-classical damping is described. The program includes a series of benchmarking problems designed to investigate various aspects of complexities, applications and limitations associated with methods for analysis of non-classically damped structures. Discussions are provided on the benchmarking process, benchmark structural models, and the evaluation approach, as well as benchmarking ground rules. It is expected that the findings and insights, as well as recommendations from this program will be useful in developing new acceptance criteria and providing guidance for future regulatory activities involving licensing applications of these alternate methods to coupled systems.

  15. NRC-BNL Benchmark Program on Evaluation of Methods for Seismic Analysis of Coupled Systems

    SciTech Connect

    Chokshi, N.; DeGrassi, G.; Xu, J.

    1999-03-24

    A NRC-BNL benchmark program for evaluation of state-of-the-art analysis methods and computer programs for seismic analysis of coupled structures with non-classical damping is described. The program includes a series of benchmarking problems designed to investigate various aspects of complexities, applications and limitations associated with methods for analysis of non-classically damped structures. Discussions are provided on the benchmarking process, benchmark structural models, and the evaluation approach, as well as benchmarking ground rules. It is expected that the findings and insights, as well as recommendations from this program will be useful in developing new acceptance criteria and providing guidance for future regulatory activities involving licensing applications of these alternate methods to coupled systems.

  16. Influence of gravity on flutter of cantilevered pipes conveying fluid

    NASA Astrophysics Data System (ADS)

    Rivero, Javier; Perez-Saborid, Miguel

    2012-11-01

    We have considered the dynamics of the nonlinear interaction between a flexible pipe and the conveyed fluid in the presence of gravity. The stability of the system (fllutter and buckling) depends on parameters such as the dimensionless fluid flow rate, the gravity to bending stiffness ratio and the fluid to pipe mass ratio and it has been studied in detail both numerically and experimentally. It has also been found that the stabilizing or destabilizing effects of fluid flow depends crucially on the direction of gravity respect to the undeformed midline of the pipe. We have also computed the post-critical behavior of the system by solving the full nonlinear equations of the problem and analyzed the transfer of energy within the system in the nonlinear regime. We have formulated the problem in terms of the angles of the midline of the pipe instead of its transverse displacements, so that we can deal with large deflections without recurring to the quasi-linear approximations concerning the pipe curvature usually made in the literature. Supported by the Ministerio de Educacin, Cultura y Deportes of Spain under grant DPI 2010-20450 C03-02.

  17. 14 CFR 27.1123 - Exhaust piping.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Exhaust piping. 27.1123 Section 27.1123... STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Exhaust System 27.1123 Exhaust piping. (a) Exhaust piping... operating temperatures. (b) Exhaust piping must be supported to withstand any vibration and inertia loads...

  18. 49 CFR 192.279 - Copper pipe.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Copper pipe. 192.279 Section 192.279 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY... Copper pipe. Copper pipe may not be threaded except that copper pipe used for joining screw fittings...

  19. 46 CFR 45.133 - Air pipes.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Air pipes. 45.133 Section 45.133 Shipping COAST GUARD....133 Air pipes. (a) Where an air pipe to any tank extends above the freeboard or superstructure deck (1) The exposed part of the air pipe must be made of steel and of sufficient thickness to...

  20. Determination of Secondary Encasement Pipe Design Pressure

    SciTech Connect

    TEDESCHI, A.R.

    2000-10-26

    This document published results of iterative calculations for maximum tank farm transfer secondary pipe (encasement) pressure upon failure of the primary pipe. The maximum pressure was calculated from a primary pipe guillotine break. Results show encasement pipeline design or testing pressures can be significantly lower than primary pipe pressure criteria.

  1. 46 CFR 154.660 - Pipe welding.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...660 Pipe welding. (a) Pipe welding must meet part 57 of...following: (1) Butt welds of pipes made from carbon, carbon...requirements for post-weld heat treatment. (2) Except for...or (ii) The nominal pipe diameter is greater than...

  2. 46 CFR 154.660 - Pipe welding.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...660 Pipe welding. (a) Pipe welding must meet part 57 of...following: (1) Butt welds of pipes made from carbon, carbon...requirements for post-weld heat treatment. (2) Except for...or (ii) The nominal pipe diameter is greater than...

  3. 46 CFR 154.660 - Pipe welding.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...660 Pipe welding. (a) Pipe welding must meet part 57 of...following: (1) Butt welds of pipes made from carbon, carbon...requirements for post-weld heat treatment. (2) Except for...or (ii) The nominal pipe diameter is greater than...

  4. 49 CFR 192.279 - Copper pipe.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...3 2011-10-01 2011-10-01 false Copper pipe. 192.279 Section 192.279 Transportation...Materials Other Than by Welding 192.279 Copper pipe. Copper pipe may not be threaded except that copper pipe...

  5. 49 CFR 192.279 - Copper pipe.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...3 2010-10-01 2010-10-01 false Copper pipe. 192.279 Section 192.279 Transportation...Materials Other Than by Welding 192.279 Copper pipe. Copper pipe may not be threaded except that copper pipe...

  6. Heat pipe technology: A bibliography with abstracts

    NASA Technical Reports Server (NTRS)

    1971-01-01

    A cumulative bibliography on heat pipe research and development projects is presented. The subjects discussed are: (1) general information, (2) heat pipe applications, (3) heat pipe theory, (4) design and fabrication, (5) testing and operation, (6) subject and author index, and (7) heat pipe related patents.

  7. 49 CFR 192.55 - Steel pipe.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Steel pipe. 192.55 Section 192.55 Transportation... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Materials 192.55 Steel pipe. (a) New steel pipe is... in accordance with paragraph (c) or (d) of this section. (b) Used steel pipe is qualified for...

  8. 49 CFR 192.55 - Steel pipe.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Steel pipe. 192.55 Section 192.55 Transportation... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Materials 192.55 Steel pipe. (a) New steel pipe is... in accordance with paragraph (c) or (d) of this section. (b) Used steel pipe is qualified for...

  9. 49 CFR 192.55 - Steel pipe.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Steel pipe. 192.55 Section 192.55 Transportation... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Materials 192.55 Steel pipe. (a) New steel pipe is... in accordance with paragraph (c) or (d) of this section. (b) Used steel pipe is qualified for...

  10. 49 CFR 192.55 - Steel pipe.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Steel pipe. 192.55 Section 192.55 Transportation... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Materials 192.55 Steel pipe. (a) New steel pipe is... in accordance with paragraph (c) or (d) of this section. (b) Used steel pipe is qualified for...

  11. 49 CFR 192.55 - Steel pipe.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Steel pipe. 192.55 Section 192.55 Transportation... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Materials 192.55 Steel pipe. (a) New steel pipe is... in accordance with paragraph (c) or (d) of this section. (b) Used steel pipe is qualified for...

  12. Heat pipe technology: A biblography with abstracts

    NASA Technical Reports Server (NTRS)

    1972-01-01

    A bibliography of heat pipe research and development projects conducted during April through June 1972, is presented. The subjects discussed are: (1) general information, (2) heat pipe applications, (3) heat pipe theory, (4) design and fabrication, (5) test and operation, (6) subject and author index, and (7) heat pipe related patents.

  13. 46 CFR 45.133 - Air pipes.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Air pipes. 45.133 Section 45.133 Shipping COAST GUARD....133 Air pipes. (a) Where an air pipe to any tank extends above the freeboard or superstructure deck (1) The exposed part of the air pipe must be made of steel and of sufficient thickness to...

  14. 46 CFR 45.133 - Air pipes.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Air pipes. 45.133 Section 45.133 Shipping COAST GUARD....133 Air pipes. (a) Where an air pipe to any tank extends above the freeboard or superstructure deck (1) The exposed part of the air pipe must be made of steel and of sufficient thickness to...

  15. 46 CFR 154.520 - Piping calculations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Piping calculations. 154.520 Section 154.520 Shipping... Process Piping Systems 154.520 Piping calculations. A piping system must be designed to meet the allowable stress values under 56.07-10 of this chapter and, if the design temperature is ?110 C (?166...

  16. 46 CFR 154.520 - Piping calculations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Piping calculations. 154.520 Section 154.520 Shipping... Process Piping Systems 154.520 Piping calculations. A piping system must be designed to meet the allowable stress values under 56.07-10 of this chapter and, if the design temperature is ?110 C (?166...

  17. 46 CFR 154.520 - Piping calculations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Piping calculations. 154.520 Section 154.520 Shipping... Process Piping Systems 154.520 Piping calculations. A piping system must be designed to meet the allowable stress values under 56.07-10 of this chapter and, if the design temperature is ?110 C (?166...

  18. 46 CFR 154.520 - Piping calculations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Piping calculations. 154.520 Section 154.520 Shipping... Process Piping Systems 154.520 Piping calculations. A piping system must be designed to meet the allowable stress values under 56.07-10 of this chapter and, if the design temperature is ?110 C (?166...

  19. Structural Assessment of Small Bore Feeder Piping

    E-print Network

    Sun, Yu

    STRESSES ON THE INTE- RIOR SURFACE OF THE PIPE AT THE LOCALLY THINNED FLAW. FURTHER TESTINGBACKGROUND Structural Assessment of Small Bore Feeder Piping Kathryn Tang, Janos Mann, Skerdi. Supervisor: A. N. Sinclair CASE ONE CANDU REACTORS HAVE 380+ SMALL BORE FEEDER PIPES. THE PIPES

  20. 46 CFR 154.520 - Piping calculations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Piping calculations. 154.520 Section 154.520 Shipping... Process Piping Systems 154.520 Piping calculations. A piping system must be designed to meet the allowable stress values under 56.07-10 of this chapter and, if the design temperature is ?110 C (?166...

  1. Sensitivity Analysis of OECD Benchmark Tests in BISON

    SciTech Connect

    Swiler, Laura Painton; Gamble, Kyle; Schmidt, Rodney C.; Williamson, Richard

    2015-09-01

    This report summarizes a NEAMS (Nuclear Energy Advanced Modeling and Simulation) project focused on sensitivity analysis of a fuels performance benchmark problem. The benchmark problem was defined by the Uncertainty Analysis in Modeling working group of the Nuclear Science Committee, part of the Nuclear Energy Agency of the Organization for Economic Cooperation and Development (OECD ). The benchmark problem involv ed steady - state behavior of a fuel pin in a Pressurized Water Reactor (PWR). The problem was created in the BISON Fuels Performance code. Dakota was used to generate and analyze 300 samples of 17 input parameters defining core boundary conditions, manuf acturing tolerances , and fuel properties. There were 24 responses of interest, including fuel centerline temperatures at a variety of locations and burnup levels, fission gas released, axial elongation of the fuel pin, etc. Pearson and Spearman correlatio n coefficients and Sobol' variance - based indices were used to perform the sensitivity analysis. This report summarizes the process and presents results from this study.

  2. An Exact Parallel Algorithm for the Maximum Satis ability Problem

    E-print Network

    Borchers, Brian

    for random MAX{3{SAT problems . . . 34 4.5 Characteristics of MAX{SAT benchmark problems . . . . . . . 36 4.6 Computational Results for MAX{SAT benchmark problems . . 37 v #12;Chapter 1 Introduction PropositAn Exact Parallel Algorithm for the Maximum Satis ability Problem by Judith D. Furman Submitted

  3. Laser profiling of sewer pipes Laser profiling of sewer pipes

    E-print Network

    Langendoen, Koen

    has to be available about the state of an asset. Nowadays CCTV inspections and pipe age are the main of. A laser profiler, as an adjunct to CCTV, can identify the profile of a sewer and also wall loss

  4. Heat pipe transient response approximation

    NASA Astrophysics Data System (ADS)

    Reid, Robert S.

    2002-01-01

    A simple and concise routine that approximates the response of an alkali metal heat pipe to changes in evaporator heat transfer rate is described. This analytically based routine is compared with data from a cylindrical heat pipe with a crescent-annular wick that undergoes gradual (quasi-steady) transitions through the viscous and condenser boundary heat transfer limits. The sonic heat transfer limit can also be incorporated into this routine for heat pipes with more closely coupled condensers. The advantages and obvious limitations of this approach are discussed. For reference, a source code listing for the approximation appears at the end of this paper. .

  5. Abrasion protection in process piping

    SciTech Connect

    Accetta, J.

    1996-07-01

    Process piping often is subjected to failure from abrasion or a combination of abrasion and corrosion. Abrasion is a complex phenomenon, with many factors involved to varying degrees. Hard, mineral based alumina ceramic and basalt materials are used to provide protection against abrasion in many piping systems. Successful life extension examples are presented from many different industries. Lined piping components require special attention with regard to operating conditions as well as design and engineering considerations. Economic justification involves direct cost comparisons and avoided costs.

  6. Thermal laminarization of a stratified pipe flow

    SciTech Connect

    Oras, J.J.; Kasza, K.E.

    1984-01-01

    The present work constitutes a new program that grew out of a scoping assessment by ANL to determine the propensity for pipe stratification to occur in the reactor outlet nozzles and hot-leg piping of a generic LMFBR during events producing reverse pipe flow. This paper focuses on the role that thermal buoyancy plays relative to being able to laminarize a turbulent stratified shear zone in a horizontal pipe. The preceeding can influence the behavior of a pipe stratified-backflow-recirculation zone (cold plenum water down into the hot pipe flow) which developes as the result of a temperature difference between the pipe flow and the plenum.

  7. Benchmarking neuromorphic systems with Nengo

    PubMed Central

    Bekolay, Trevor; Stewart, Terrence C.; Eliasmith, Chris

    2015-01-01

    Nengo is a software package for designing and simulating large-scale neural models. Nengo is architected such that the same Nengo model can be simulated on any of several Nengo backends with few to no modifications. Backends translate a model to specific platforms, which include GPUs and neuromorphic hardware. Nengo also contains a large test suite that can be run with any backend and focuses primarily on functional performance. We propose that Nengo's large test suite can be used to benchmark neuromorphic hardware's functional performance and simulation speed in an efficient, unbiased, and future-proof manner. We implement four benchmark models and show that Nengo can collect metrics across five different backends that identify situations in which some backends perform more accurately or quickly. PMID:26539076

  8. Geothermal Heat Pump Benchmarking Report

    SciTech Connect

    1997-01-17

    A benchmarking study was conducted on behalf of the Department of Energy to determine the critical factors in successful utility geothermal heat pump programs. A Successful program is one that has achieved significant market penetration. Successfully marketing geothermal heat pumps has presented some major challenges to the utility industry. However, select utilities have developed programs that generate significant GHP sales. This benchmarking study concludes that there are three factors critical to the success of utility GHP marking programs: (1) Top management marketing commitment; (2) An understanding of the fundamentals of marketing and business development; and (3) An aggressive competitive posture. To generate significant GHP sales, competitive market forces must by used. However, because utilities have functioned only in a regulated arena, these companies and their leaders are unschooled in competitive business practices. Therefore, a lack of experience coupled with an intrinsically non-competitive culture yields an industry environment that impedes the generation of significant GHP sales in many, but not all, utilities.

  9. Benchmarking neuromorphic systems with Nengo.

    PubMed

    Bekolay, Trevor; Stewart, Terrence C; Eliasmith, Chris

    2015-01-01

    Nengo is a software package for designing and simulating large-scale neural models. Nengo is architected such that the same Nengo model can be simulated on any of several Nengo backends with few to no modifications. Backends translate a model to specific platforms, which include GPUs and neuromorphic hardware. Nengo also contains a large test suite that can be run with any backend and focuses primarily on functional performance. We propose that Nengo's large test suite can be used to benchmark neuromorphic hardware's functional performance and simulation speed in an efficient, unbiased, and future-proof manner. We implement four benchmark models and show that Nengo can collect metrics across five different backends that identify situations in which some backends perform more accurately or quickly. PMID:26539076

  10. Training reduces stuck pipe costs and incidents

    SciTech Connect

    Watson, B. ); Smith, R. )

    1994-09-19

    Properly administered initial and refresher stuck pipe training courses have dramatically reduced the cost and number of stuck pipe incidents for many companies worldwide. These training programs have improved operator and contractor crew awareness of stuck pipe risks and fostered a team commitment in averting such incidents. The success is evident in the achievements of the companies sponsoring such training. Preventing and minimizing stuck pipe is the most significant benefit of stuck pipe training, but crews also benefit from becoming more knowledgeable about the drilling program and equipment operation. The paper discusses stuck pipe costs, stuck pipe training, prevention of stuck pipes, well bore stability, geopressured formation, reactive formation, reactive formations, unconsolidated formations, mobile formations, fractured and faulted formations, differential sticking, 8 other causes of stuck pipe, and freeing stuck pipe.

  11. MPI Multicore Torus Communication Benchmark

    SciTech Connect

    2008-02-05

    The MPI Multicore Torus Communications Benchmark (TorusTest) measues the aggegate bandwidth across all six links from/to any multicore node in a logical torus. It can run in wo modi: using a static or a random mapping of tasks to torus locations. The former can be used to achieve optimal mappings and aggregate bandwidths that can be achieved with varying node mappings.

  12. Restaurant Energy Use Benchmarking Guideline

    SciTech Connect

    Hedrick, R.; Smith, V.; Field, K.

    2011-07-01

    A significant operational challenge for food service operators is defining energy use benchmark metrics to compare against the performance of individual stores. Without metrics, multiunit operators and managers have difficulty identifying which stores in their portfolios require extra attention to bring their energy performance in line with expectations. This report presents a method whereby multiunit operators may use their own utility data to create suitable metrics for evaluating their operations.

  13. Overdetermined problems with possibly degenerate ellipticity, a geometric approach

    E-print Network

    Kawohl, Bernd

    tangential stress on the pipe wall is the same at all points of the wall if and only if the pipe has parallel streamlines through a pipe with planar section or the torsion of a solid straight bar of given for some p > 1, problem (1) models torsional creep with constant stress on the boundary [21]. When A(t) = 1

  14. DRAINAGE PIPE DETECTOR: GROUND PENETRATING RADAR SHOWS PROMISE IN LOCATING BURIED SYSTEMS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One of the more frustrating problems confronting farmers and land improvement contractors in the Midwestern United States involves locating buried agricultural drainage pipes. Conventional geophysical methods, particularly ground penetrating radar (GPR), presently being used for environmental and co...

  15. RISKIND verification and benchmark comparisons

    SciTech Connect

    Biwer, B.M.; Arnish, J.J.; Chen, S.Y.; Kamboj, S.

    1997-08-01

    This report presents verification calculations and benchmark comparisons for RISKIND, a computer code designed to estimate potential radiological consequences and health risks to individuals and the population from exposures associated with the transportation of spent nuclear fuel and other radioactive materials. Spreadsheet calculations were performed to verify the proper operation of the major options and calculational steps in RISKIND. The program is unique in that it combines a variety of well-established models into a comprehensive treatment for assessing risks from the transportation of radioactive materials. Benchmark comparisons with other validated codes that incorporate similar models were also performed. For instance, the external gamma and neutron dose rate curves for a shipping package estimated by RISKIND were compared with those estimated by using the RADTRAN 4 code and NUREG-0170 methodology. Atmospheric dispersion of released material and dose estimates from the GENII and CAP88-PC codes. Verification results have shown the program to be performing its intended function correctly. The benchmark results indicate that the predictions made by RISKIND are within acceptable limits when compared with predictions from similar existing models.

  16. 226 IEEE JOURNAL OF OCEANIC ENGINEERING, VOL. 22, NO. 2, APRIL 1997 Benchmarks for Validating Range-Dependent

    E-print Network

    Gerstoft, Peter

    and below by an inhomogeneous, multilayered elastic sea bed. Further, the acoustic properties of the water- dependent seismo-acoustic codes. In this paper, we present a collection of problems intended for general use are applied to produce reference solutions for these benchmarks. Index Terms--Benchmarking, elastic, modeling

  17. B Plant process piping replacement feasibility study

    SciTech Connect

    Howden, G.F.

    1996-02-07

    Reports on the feasibility of replacing existing embedded process piping with new more corrosion resistant piping between cells and between cells and a hot pipe trench of a Hanford Site style canyon facility. Provides concepts for replacement piping installation, and use of robotics to replace the use of the canyon crane as the primary means of performing/supporting facility modifications (eg, cell lining, pipe replacement, equipment reinstallation) and operational maintenenace.

  18. Intermediate Temperature Water Heat Pipe Tests

    NASA Technical Reports Server (NTRS)

    Devarakonda, Angirasa; Xiong, Daxi; Beach, Duane E.

    2004-01-01

    Heat pipes are among the most promising technologies for space radiator systems. Water heat pipes are explored in the intermediate temperature range of 400 to above 500 K. The thermodynamic and thermo-physical properties of water are reviewed in this temperature range. Test Data are reported for a copper-water heat pipe. The heat pipe was tested under different orientations. Water heat pipes show promise in this temperature range.Fabrication and testing issues are being addressed.

  19. Intermediate Temperature Water Heat Pipe Tests

    NASA Technical Reports Server (NTRS)

    Devarakonda, Angirasa; Xiong, Da-Xi; Beach, Duane E.

    2005-01-01

    Heat pipes are among the most promising technologies for space radiator systems. Water heat pipes are explored in the intermediate temperature range of 400 to above 500 K. The thermodynamic and thermo-physical properties of water are reviewed in this temperature range. Test data are reported for a copper-water heat pipe. The heat pipe was tested under different orientations. Water heat pipes show promise in this temperature range. Fabrication and testing issues are being addressed.

  20. Agricultural drainage pipe detection using ground penetrating radar: Effects of antenna orientation relative to drainage pipe directional trend

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Locating buried agricultural drainage pipes is a difficult problem confronting farmers and land improvement contractors, especially in the Midwest U.S., where the removal of excess soil water using subsurface drainage systems is a common farm practice. Enhancing the efficiency of soil water removal ...

  1. Heat pipe radiators for space

    NASA Technical Reports Server (NTRS)

    Sellers, J. P.

    1976-01-01

    Analysis of the data heat pipe radiator systems tested in both vacuum and ambient environments was continued. The systems included (1) a feasibility VCHP header heat-pipe panel, (2) the same panel reworked to eliminate the VCHP feature and referred to as the feasibility fluid header panel, and (3) an optimized flight-weight fluid header panel termed the 'prototype.' A description of freeze-thaw thermal vacuum tests conducted on the feasibility VCHP was included. In addition, the results of ambient tests made on the feasibility fluid header are presented, including a comparison with analytical results. A thermal model of a fluid header heat pipe radiator was constructed and a computer program written. The program was used to make a comparison of the VCHP and fluid-header concepts for both single and multiple panel applications. The computer program was also employed for a parametric study, including optimum feeder heat pipe spacing, of the prototype fluid header.

  2. Physics of heat pipe rewetting

    NASA Technical Reports Server (NTRS)

    Chan, S. H.

    1994-01-01

    This is the final report which summarizes the research accomplishments under the project entitled 'Physics of Heat Pipe Rewetting' under NASA Grant No. NAG 9-525, Basic, during the period of April 1, 1991 to January 31, 1994. The objective of the research project was to investigate both analytically and experimentally the rewetting characteristics of the heated, grooved plate. The grooved plate is to simulate the inner surface of the vapor channel in monogroove heat pipes for space station design. In such designs, the inner surface of the vapor channel is threaded with monogrooves. When the heat pipe is thermally overloaded, dryout of the monogroove surface occurs. Such a dryout surface should be promptly rewetted to prevent the failure of the heat pipe operation in the thermal radiator of the space station.

  3. Method for casting polyethylene pipe

    NASA Technical Reports Server (NTRS)

    Elam, R. M., Jr.

    1973-01-01

    Short lengths of 7-cm ID polyethylene pipe are cast in a mold which has a core made of room-temperature-vulcanizable (RTV) silicone. Core expands during casting and shrinks on cooling to allow for contraction of the polyethylene.

  4. Heat Pipes: An Industrial Application

    E-print Network

    Murray, F.

    1984-01-01

    This paper reviews the basics of heat pipe exchangers. Included are how they are constructed, how they operate, where they have application, and various aspects of evaluating a potential application. After discussing the technical aspects of heat...

  5. Corrugated pipe adhesive applicator apparatus

    DOEpatents

    Shirey, R.A.

    1983-06-14

    Apparatus for coating selected portions of the troughs of a corrugated pipe with an adhesive includes a support disposed within the pipe with a reservoir containing the adhesive disposed on the support. A pump, including a spout, is utilized for supplying the adhesive from the reservoir to a trough of the pipe. A rotatable applicator is supported on the support and contacts the trough of the pipe. The applicator itself is sized so as to fit within the trough, and contacts the adhesive in the trough and spreads the adhesive in the trough upon rotation. A trough shield, supported by the support and disposed in the path of rotation of the applicator, is utilized to prevent the applicator from contacting selected portions of the trough. A locator head is also disposed on the support and provides a way for aligning the spout, the applicator, and the trough shield with the trough. 4 figs.

  6. Loop Heat Pipe Startup Behaviors

    NASA Technical Reports Server (NTRS)

    Ku, Jentung

    2014-01-01

    A loop heat pipe must start successfully before it can commence its service. The start-up transient represents one of the most complex phenomena in the loop heat pipe operation. This paper discusses various aspects of loop heat pipe start-up behaviors. Topics include the four start-up scenarios, the initial fluid distribution between the evaporator and reservoir that determines the start-up scenario, factors that affect the fluid distribution between the evaporator and reservoir, difficulties encountered during the low power start-up, and methods to enhance the start-up success. Also addressed are the thermodynamic constraint between the evaporator and reservoir in the loop heat pipe operation, the superheat requirement for nucleate boiling, pressure spike and pressure surge during the start-up transient, and repeated cycles of loop start-up andshutdown under certain conditions.

  7. Meteoroid Protection Methods for Spacecraft Radiators Using Heat Pipes

    NASA Technical Reports Server (NTRS)

    Ernst, D. M.

    1979-01-01

    Various aspects of achieving a low mass heat pipe radiator for the nuclear electric propulsion spacecraft were studied. Specific emphasis was placed on a concept applicable to a closed Brayton cycle power sub-system. Three aspects of inter-related problems were examined: (1) the armor for meteoroid protection, (2) emissivity of the radiator surface, and (3) the heat pipe itself. The study revealed several alternatives for the achievement of the stated goal, but a final recommendation for the best design requires further investigation.

  8. Heat Pipe Thermal Conditioning Panel

    NASA Technical Reports Server (NTRS)

    Saaski, E. W.

    1973-01-01

    The technology involved in designing and fabricating a heat pipe thermal conditioning panel to satisfy a broad range of thermal control system requirements on NASA spacecraft is discussed. The design specifications were developed for a 30 by 30 inch heat pipe panel. The fundamental constraint was a maximum of 15 gradient from source to sink at 300 watts input and a flux density of 2 watts per square inch. The results of the performance tests conducted on the panel are analyzed.

  9. PAULA: A 3D code for analysis of nonlinear pipes

    SciTech Connect

    Lazzeri, L.; Agrone, M.; Scala, M.

    1982-11-01

    A 3D code is described with a complete capability in the field of nonlinear incremental dynamics. A special finite element library has been added; an accurate modeling of many items typical of pipe lines is possible. Some uncertainties in modelling have been identified (crack development, dynamic effects on material properties, change of section, instability, 3D effects on restraints). Work is in progress to solve these problems using, in the main, available experimental data. Some runs have been performed on typical geometries and comparisons with a simplified 2D code have been made. The 2D analyses generally give results accurate enough for the sizing of the restraint which they model. The general pattern of the modeled pipe movements is generally correct. However, some 3D effects take place such as loading on restraints other than the ones modelled in the 2D analyses (secondary restraints loading), axial movements of the pipe and consequent out of plane loading of the restraints. These 3D effects may not be important depending on the geometry which is under examination. Some examples referring to conditions in which these effects are not quite negligible have been given. However, it is estimated that a 2D analysis is quite often sufficient even though care and experience are necessary to identify abnormal cases and formulate modeling assumptions. If a 3D analysis is performed, then the special characteristics of the piping (T joint, elbows, pipe restraint interaction) are to be modeled with utmost care. Some phenomena between pipe and restraint take place. These phenomena may have large influence on the overall behaviour of the pipe restraint and should be considered.

  10. Pipe weld crown removal device

    DOEpatents

    Sword, Charles K. (Pleasant Hills, PA); Sette, Primo J. (West Newton, PA)

    1992-01-01

    A device is provided for grinding down the crown of a pipe weld joining aligned pipe sections so that the weld is substantially flush with the pipe sections joined by the weld. The device includes a cage assembly comprising a pair of spaced cage rings adapted to be mounted for rotation on the respective pipe sections on opposite sides of the weld, a plurality of grinding wheels, supported by the cage assembly for grinding down the crown of the weld, and a plurality of support shafts, each extending longitudinally along the joined pipe sections, parallel thereto, for individually mounting respective grinding wheels. Each end of the support shafts is mounted for rotation in a bearing assembly housed within a radially directed opening in a corresponding one of the cage rings so as to provide radial movement of the associated shaft, and thus of the associated grinding wheel, towards and away from the weld. A first drive sprocket provides rotation of the cage assembly around the pipe sections while a second drive unit, driven by a common motor, provides rotation of the grinding wheels.

  11. Heat pipe cooled power magnetics

    NASA Technical Reports Server (NTRS)

    Chester, M. S.

    1979-01-01

    A high frequency, high power, low specific weight (0.57 kg/kW) transformer developed for space use was redesigned with heat pipe cooling allowing both a reduction in weight and a lower internal temperature rise. The specific weight of the heat pipe cooled transformer was reduced to 0.4 kg/kW and the highest winding temperature rise was reduced from 40 C to 20 C in spite of 10 watts additional loss. The design loss/weight tradeoff was 18 W/kg. Additionally, allowing the same 40 C winding temperature rise as in the original design, the KVA rating is increased to 4.2 KVA, demonstrating a specific weight of 0.28 kg/kW with the internal loss increased by 50W. This space environment tested heat pipe cooled design performed as well electrically as the original conventional design, thus demonstrating the advantages of heat pipes integrated into a high power, high voltage magnetic. Another heat pipe cooled magnetic, a 3.7 kW, 20A input filter inductor was designed, developed, built, tested, and described. The heat pipe cooled magnetics are designed to be Earth operated in any orientation.

  12. Superconducting pipes and levitating magnets

    E-print Network

    Yan Levin; Felipe B. Rizzato

    2006-09-15

    Motivated by a beautiful demonstration of the Faraday's and Lenz's law in which a small neodymium magnet falls slowly through a conducting non-ferromagnetic tube, we consider the dynamics of a magnet falling through a superconducting pipe. Unlike the case of normal conducting pipes, in which the magnet quickly reaches the terminal velocity, inside a superconducting tube the magnet falls freely. On the other hand, to enter the pipe the magnet must overcome a large electromagnetic energy barrier. For sufficiently strong magnets, the barrier is so large that the magnet will not be able to penetrate it and will be suspended over the front edge. We calculate the work that must done to force the magnet to enter a superconducting tube. The calculations show that superconducting pipes are very efficient at screening magnetic fields. For example, the magnetic field of a dipole at the center of a short pipe of radius $a$ and length $L \\approx a$ decays, in the axial direction, with a characteristic length $\\xi \\approx 0.26 a$. The efficient screening of the magnetic field might be useful for shielding highly sensitive superconducting quantum interference devices, SQUIDs. Finally, the motion of the magnet through a superconducting pipe is compared and contrasted to the flow of ions through a trans-membrane channel.

  13. Automated internal pipe cutting device

    DOEpatents

    Godlewski, William J. (Clifton Park, NY); Haffke, Gary S. (Ballston Spa, NY); Purvis, Dale (Amsterdam, NY); Bashar, Ronald W. (Oakdale, CT); Jones, Stewart D. (Mechanicville, NY); Moretti, Jr., Henry (Cranston, RI); Pimentel, James (Warwick, RI)

    2003-01-21

    The invention is a remotely controlled internal pipe cutting device primarily used for cutting pipes where the outside of the pipe is inaccessible at the line where the cut is to be made. The device includes an axial ram within a rotational cylinder which is enclosed in a housing. The housing is adapted for attachment to an open end of the pipe and for supporting the ram and cylinder in cantilever fashion within the pipe. A radially movable cutter, preferably a plasma arc torch, is attached to the distal end of the ram. A drive mechanism, containing motors and mechanical hardware for operating the ram and cylinder, is attached to the proximal end of the housing. The ram and cylinder provide for moving the cutter axially and circumferentially, and a cable assembly attached to a remote motor provide for the movement of the cutter radially, within the pipe. The control system can be adjusted and operated remotely to control the position and movement of the cutter to obtain the desired cut. The control system can also provide automatic standoff control for a plasma arc torch.

  14. Performance of Multi-chaotic PSO on a shifted benchmark functions set

    SciTech Connect

    Pluhacek, Michal; Senkerik, Roman; Zelinka, Ivan

    2015-03-10

    In this paper the performance of Multi-chaotic PSO algorithm is investigated using two shifted benchmark functions. The purpose of shifted benchmark functions is to simulate the time-variant real-world problems. The results of chaotic PSO are compared with canonical version of the algorithm. It is concluded that using the multi-chaotic approach can lead to better results in optimization of shifted functions.

  15. Pseudo-nonlinear dynamic analysis of buckled pipes

    NASA Astrophysics Data System (ADS)

    Gltekin S?n?r, B.

    2013-02-01

    In this study, the post-divergence behavior of fluid-conveying pipes supported at both ends is investigated using the nonlinear equations of motion. The governing equation exhibits a cubic nonlinearity arising from mid-plane stretching. Exact solutions for post-buckling configurations of pipes with fixed-fixed, fixed-hinged, and hinged-hinged boundary conditions are investigated. The pipe is stable at its original static equilibrium position until the flow velocity becomes high enough to cause a supercritical pitchfork bifurcation, and the pipe loses stability by static divergence. In the supercritical fluid velocity regime, the equilibrium configuration becomes unstable and bifurcates into multiple equilibrium positions. To investigate the vibrations that occur in the vicinity of a buckled equilibrium position, the pseudo-nonlinear vibration problem around the first buckled configuration is solved precisely using a new solution procedure. By solving the resulting eigenvalue problem, the natural frequencies and the associated mode shapes of the pipe are calculated. The dynamic stability of the post-buckling configurations obtained in this manner is investigated. The first buckled shape is a stable equilibrium position for all boundary conditions. The buckled configurations beyond the first buckling mode are unstable equilibrium positions. The natural frequencies of the lowest vibration modes around each of the first two buckled configurations are presented. Effects of the system parameters on pipe behavior as well as the possibility of a subcritical pitchfork bifurcation are also investigated. The results show that many internal resonances might be activated among the vibration modes around the same or different buckled configurations.

  16. Benchmarking for Excellence and the Nursing Process

    NASA Technical Reports Server (NTRS)

    Sleboda, Claire

    1999-01-01

    Nursing is a service profession. The services provided are essential to life and welfare. Therefore, setting the benchmark for high quality care is fundamental. Exploring the definition of a benchmark value will help to determine a best practice approach. A benchmark is the descriptive statement of a desired level of performance against which quality can be judged. It must be sufficiently well understood by managers and personnel in order that it may serve as a standard against which to measure value.

  17. Computational Chemistry Comparison and Benchmark Database

    National Institute of Standards and Technology Data Gateway

    SRD 101 NIST Computational Chemistry Comparison and Benchmark Database (Web, free access) The NIST Computational Chemistry Comparison and Benchmark Database is a collection of experimental and ab initio thermochemical properties for a selected set of molecules. The goals are to provide a benchmark set of molecules for the evaluation of ab initio computational methods and allow the comparison between different ab initio computational methods for the prediction of thermochemical properties.

  18. NASA Software Engineering Benchmarking Effort

    NASA Technical Reports Server (NTRS)

    Godfrey, Sally; Rarick, Heather

    2012-01-01

    Benchmarking was very interesting and provided a wealth of information (1) We did see potential solutions to some of our "top 10" issues (2) We have an assessment of where NASA stands with relation to other aerospace/defense groups We formed new contacts and potential collaborations (1) Several organizations sent us examples of their templates, processes (2) Many of the organizations were interested in future collaboration: sharing of training, metrics, Capability Maturity Model Integration (CMMI) appraisers, instructors, etc. We received feedback from some of our contractors/ partners (1) Desires to participate in our training; provide feedback on procedures (2) Welcomed opportunity to provide feedback on working with NASA

  19. The Zoo, Benchmarks & You: How To Reach the Oregon State Benchmarks with Zoo Resources.

    ERIC Educational Resources Information Center

    2002

    This document aligns Oregon state educational benchmarks and standards with Oregon Zoo resources. Benchmark areas examined include English, mathematics, science, social studies, and career and life roles. Brief descriptions of the programs offered by the zoo are presented. (SOE)

  20. Course Title Credits Critical Benchmark(s) Strongly Recommended BC 192 Biochemistry Freshman Seminar 2

    E-print Network

    Beveridge, Ross

    Course Title Credits Critical Benchmark(s) Strongly Recommended BC 192 Biochemistry Freshman University Biochemistry (B.S.) General Biochemistry Concentration Distinctive Requirements for Degree Program TO PREPARE FOR FIRST SEMESTER: The curriculum for the Biochemistry major General Biochemistry

  1. Magnetic refrigeration apparatus with heat pipes

    DOEpatents

    Barclay, John A. (Los Alamos, NM); Prenger, Jr., F. Coyne (Madison, WI)

    1987-01-01

    A magnetic refrigerator operating in the 4 to 20 K range utilizes heat pipes to transfer heat to and from the magnetic material at the appropriate points during the material's movement. In one embodiment circular disks of magnetic material can be interleaved with the ends of the heat pipes. In another embodiment a mass of magnetic material reciprocatingly moves between the end of the heat pipe of pipes that transmits heat from the object of cooling to the magnetic material and the end of the heat pipe or pipes that transmits heat from the magnetic material to a heat sink.

  2. Heat pipe power depending on its position

    NASA Astrophysics Data System (ADS)

    Mancikova, Veronika; Caja, Alexander; Malcho, Milan

    2014-08-01

    The heat pipe, also named two-phase thermo syphon, is utilized for heat transport. The gravity support is needed for condensate return of such heat pipe. The advantage of this heat pipe is that it can also workindifferenttiltangles compare to other heat pipes. The experimental measurements were carried out for the heat pipe at different tilt angles. In order to find out a dependence of performance on the position of the heat pipe were performed calculations. As a working fluid was used fluorinert FC 72.

  3. Magnetic refrigeration apparatus with heat pipes

    DOEpatents

    Barclay, J.A.; Prenger, F.C. Jr.

    1985-10-25

    A magnetic refrigerator operating in the 4 to 20 K range utilizes heat pipes to transfer heat to and from the magnetic material at the appropriate points during the material's movement. In one embodiment circular disks of magnetic material can be interleaved with the ends of the heat pipes. In another embodiment a mass of magnetic material reciprocatingly moves between the end of the heat pipe or pipes that transmits heat from the object of cooling to the magnetic material and the end of the heat pipe or pipes that transmits heat from the magnetic material to a heat sink.

  4. Modeling coupled blast/structure interaction with Zapotec, benchmark calculations for the Conventional Weapon Effects Backfill (CONWEB) tests.

    SciTech Connect

    Bessette, Gregory Carl

    2004-09-01

    Modeling the response of buried reinforced concrete structures subjected to close-in detonations of conventional high explosives poses a challenge for a number of reasons. Foremost, there is the potential for coupled interaction between the blast and structure. Coupling enters the problem whenever the structure deformation affects the stress state in the neighboring soil, which in turn, affects the loading on the structure. Additional challenges for numerical modeling include handling disparate degrees of material deformation encountered in the structure and surrounding soil, modeling the structure details (e.g., modeling the concrete with embedded reinforcement, jointed connections, etc.), providing adequate mesh resolution, and characterizing the soil response under blast loading. There are numerous numerical approaches for modeling this class of problem (e.g., coupled finite element/smooth particle hydrodynamics, arbitrary Lagrange-Eulerian methods, etc.). The focus of this work will be the use of a coupled Euler-Lagrange (CEL) solution approach. In particular, the development and application of a CEL capability within the Zapotec code is described. Zapotec links two production codes, CTH and Pronto3D. CTH, an Eulerian shock physics code, performs the Eulerian portion of the calculation, while Pronto3D, an explicit finite element code, performs the Lagrangian portion. The two codes are run concurrently with the appropriate portions of a problem solved on their respective computational domains. Zapotec handles the coupling between the two domains. The application of the CEL methodology within Zapotec for modeling coupled blast/structure interaction will be investigated by a series of benchmark calculations. These benchmarks rely on data from the Conventional Weapons Effects Backfill (CONWEB) test series. In these tests, a 15.4-lb pipe-encased C-4 charge was detonated in soil at a 5-foot standoff from a buried test structure. The test structure was composed of a reinforced concrete slab bolted to a reaction structure. Both the slab thickness and soil media were varied in the test series. The wealth of data obtained from these tests along with the variations in experimental setups provide ample opportunity to assess the robustness of the Zapotec CEL methodology.

  5. Method and system for benchmarking computers

    DOEpatents

    Gustafson, John L. (Ames, IA)

    1993-09-14

    A testing system and method for benchmarking computer systems. The system includes a store containing a scalable set of tasks to be performed to produce a solution in ever-increasing degrees of resolution as a larger number of the tasks are performed. A timing and control module allots to each computer a fixed benchmarking interval in which to perform the stored tasks. Means are provided for determining, after completion of the benchmarking interval, the degree of progress through the scalable set of tasks and for producing a benchmarking rating relating to the degree of progress for each computer.

  6. Research on the ITOC based scheduling system for ship piping production

    NASA Astrophysics Data System (ADS)

    Li, Rui; Liu, Yu-Jun; Hamada, Kunihiro

    2010-12-01

    Manufacturing of ship piping systems is one of the major production activities in shipbuilding. The schedule of pipe production has an important impact on the master schedule of shipbuilding. In this research, the ITOC concept was introduced to solve the scheduling problems of a piping factory, and an intelligent scheduling system was developed. The system, in which a product model, an operation model, a factory model, and a knowledge database of piping production were integrated, automated the planning process and production scheduling. Details of the above points were discussed. Moreover, an application of the system in a piping factory, which achieved a higher level of performance as measured by tardiness, lead time, and inventory, was demonstrated.

  7. Holographic NDT methods for plastic pipe vibration and brittle crack propagation analysis

    NASA Astrophysics Data System (ADS)

    Markov, Vladimir B.; Boone, Pierre M.; Vanspeybroeck, Philippe

    1995-11-01

    Plastic pipes are frequently used for low pressure gas and water distribution. One of the main problems with their wide commercial applications is rapid crack propagation (RCP). This results in enormous losses of energy resources and environment pollution. Recent incidents show that it is of importance to find criteria to assess the safety conditions for large diameter piping before its installation. In this report some results of holographic non-destructive testing of plastic pipes are presented. Double-pulse holographic interferometry measurements of stress distribution at small scale steady state (S4) tests for 3 - 5 bar pressurized plastic pipes with (phi) 110 mm to 200 mm were performed. Also the mechanically induced vibration modes of non-pressurized (phi) 200 mm plastic pipe were visualized with the purpose to check stress distribution.

  8. [Study on the automatic parameters identification of water pipe network model].

    PubMed

    Jia, Hai-Feng; Zhao, Qi-Feng

    2010-01-01

    Based on the problems analysis on development and application of water pipe network model, the model parameters automatic identification is regarded as a kernel bottleneck of model's application in water supply enterprise. The methodology of water pipe network model parameters automatic identification based on GIS and SCADA database is proposed. Then the kernel algorithm of model parameters automatic identification is studied, RSA (Regionalized Sensitivity Analysis) is used for automatic recognition of sensitive parameters, and MCS (Monte-Carlo Sampling) is used for automatic identification of parameters, the detail technical route based on RSA and MCS is presented. The module of water pipe network model parameters automatic identification is developed. At last, selected a typical water pipe network as a case, the case study on water pipe network model parameters automatic identification is conducted and the satisfied results are achieved. PMID:20329520

  9. HPC Analytics Support. Requirements for Uncertainty Quantification Benchmarks

    SciTech Connect

    Paulson, Patrick R.; Purohit, Sumit; Rodriguez, Luke R.

    2015-05-01

    This report outlines techniques for extending benchmark generation products so they support uncertainty quantification by benchmarked systems. We describe how uncertainty quantification requirements can be presented to candidate analytical tools supporting SPARQL. We describe benchmark data sets for evaluating uncertainty quantification, as well as an approach for using our benchmark generator to produce data sets for generating benchmark data sets.

  10. Flexible ultrasonic pipe inspection apparatus

    DOEpatents

    Jenkins, C.F.; Howard, B.D.

    1998-06-23

    A flexible, modular ultrasonic pipe inspection apparatus, comprises a flexible, hollow shaft that carries a plurality of modules, including at least one rotatable ultrasonic transducer, a motor/gear unit, and a position/signal encoder. The modules are connected by flexible knuckle joints that allow each module of the apparatus to change its relative orientation with respect to a neighboring module, while the shaft protects electrical wiring from kinking or buckling while the apparatus moves around a tight corner. The apparatus is moved through a pipe by any suitable means, including a tether or drawstring attached to the nose or tail, differential hydraulic pressure, or a pipe pig. The rotational speed of the ultrasonic transducer and the forward velocity of the apparatus are coordinated so that the beam sweeps out the entire interior surface of the pipe, enabling the operator to accurately assess the condition of the pipe wall and determine whether or not leak-prone corrosion damage is present. 7 figs.

  11. Centrally activated pipe snubbing system

    DOEpatents

    Cawley, William E. (Richland, WA)

    1985-01-01

    An electromechanical pipe snubbing system and an electromechanical pipe snubber. In the system, each pipe snubber, in a set of pipe snubbers, has an electromechanical mechanism to lock and unlock the snubber. A sensor, such as a seismometer, measures a quantity related to making a snubber locking or unlocking decision. A control device makes an electrical connection between a power supply and each snubber's electromechanical mechanism to simultaneously lock each snubber when the sensor measurement indicates a snubber locking condition. The control device breaks the connection to simultaneously unlock each snubber when the sensor measurement indicates a snubber unlocking condition. In the snubber, one end of the shaft slides within a bore in one end of a housing. The other end of the shaft is rotatably attached to a pipe; the other end of the housing is rotatively attached to a wall. The snubber's electromechanical mechanism locks the slidable end of the shaft to the housing and unlocks that end from the housing. The electromechanical mechanism permits remote testing and lockup status indication for each snubber.

  12. Pipe crawler with extendable legs

    DOEpatents

    Zollinger, W.T.

    1992-06-16

    A pipe crawler for moving through a pipe in inchworm fashion having front and rear leg assemblies separated by air cylinders to increase and decrease the spacing between assemblies. Each leg of the four legs of an assembly is moved between a wall-engaging, extended position and a retracted position by a separate air cylinder. The air cylinders of the leg assemblies are preferably arranged in pairs of oppositely directed cylinders with no pair lying in the same axial plane as another pair. Therefore, the cylinders can be as long as a leg assembly is wide and the crawler can crawl through sections of pipes where the diameter is twice that of other sections. The crawler carries a valving system, a manifold to distribute air supplied by a single umbilical air hose to the various air cylinders in a sequence controlled electrically by a controller. The crawler also utilizes a rolling mechanism, casters in this case, to reduce friction between the crawler and pipe wall thereby further extending the range of the pipe crawler. 8 figs.

  13. Pipe crawler with extendable legs

    DOEpatents

    Zollinger, William T. (3927 Almon Dr., Martinez, GA 30907)

    1992-01-01

    A pipe crawler for moving through a pipe in inchworm fashion having front and rear leg assemblies separated by air cylinders to increase and decrease the spacing between assemblies. Each leg of the four legs of an assembly is moved between a wall-engaging, extended position and a retracted position by a separate air cylinder. The air cylinders of the leg assemblies are preferably arranged in pairs of oppositely directed cylinders with no pair lying in the same axial plane as another pair. Therefore, the cylinders can be as long a leg assembly is wide and the crawler can crawl through sections of pipes where the diameter is twice that of other sections. The crawler carries a valving system, a manifold to distribute air supplied by a single umbilical air hose to the various air cylinders in a sequence controlled electrically by a controller. The crawler also utilizes a rolling mechanism, casters in this case, to reduce friction between the crawler and pipe wall thereby further extending the range of the pipe crawler.

  14. Superconducting pipes and levitating magnets

    E-print Network

    Levin, Y; Levin, Yan; Rizzato, Felipe B.

    2006-01-01

    Motivated by a beautiful demonstration of the Faraday's and Lenz's law in which a small neodymium magnet falls slowly through a conducting non-ferromagnetic tube, we consider the dynamics of a magnet falling through a superconducting pipe. Unlike the case of normal conducting pipes, in which the magnet quickly reaches the terminal velocity, inside a superconducting tube the magnet falls freely. On the other hand, to enter the pipe the magnet must overcome a large electromagnetic energy barrier. For sufficiently strong magnets, the barrier is so large that the magnet will not be able to penetrate it and will be suspended over the front edge. We calculate the work that must done to force the magnet to enter a superconducting tube. The calculations show that superconducting pipes are very efficient at screening magnetic fields. For example, the magnetic field of a dipole at the center of a short pipe of radius $a$ and length $L \\approx a$ decays, in the axial direction, with a characteristic length $\\xi \\approx ...

  15. A Benders approach for the constrained minimum break problem

    E-print Network

    Grossmann, Ignacio E.

    - gorithm is capable of solving a number of previously unsolved benchmark problems for the Traveling structures, as well as challenging benchmark problems still unsolved by state of the art algorithms, likeA Benders approach for the constrained minimum break problem Rasmus V. Rasmussen1 and Michael A

  16. : An integrated library of multi-dimensional packing problems q

    E-print Network

    Fekete, Sándor P.

    and cutting; Benchmark library; Multi-dimensional packing; Open problems; XML 1. Introduction A crucial and maintaining benchmark libraries for a large variety of problems. In operations research, one of the firstPackLib2 : An integrated library of multi-dimensional packing problems q Sa´ndor P. Fekete, Jan C

  17. Assessing secondary structure assignment of protein structures by using pairwise sequence-alignment benchmarks.

    PubMed

    Zhang, Wei; Dunker, A Keith; Zhou, Yaoqi

    2008-04-01

    How to make an objective assignment of secondary structures based on a protein structure is an unsolved problem. Defining the boundaries between helix, sheet, and coil structures is arbitrary, and commonly accepted standard assignments do not exist. Here, we propose a criterion that assesses secondary structure assignment based on the similarity of the secondary structures assigned to pairwise sequence-alignment benchmarks, where these benchmarks are determined by prior structural alignments of the protein pairs. This criterion is used to rank six secondary structure assignment methods: STRIDE, DSSP, SECSTR, KAKSI, P-SEA, and SEGNO with three established sequence-alignment benchmarks (PREFAB, SABmark, and SALIGN). STRIDE and KAKSI achieve comparable success rates in assigning the same secondary structure elements to structurally aligned residues in the three benchmarks. Their success rates are between 1-4% higher than those of the other four methods. The consensus of STRIDE, KAKSI, SECSTR, and P-SEA, called SKSP, improves assignments over the best single method in each benchmark by an additional 1%. These results support the usefulness of the sequence-alignment benchmarks as a means to evaluate secondary structure assignment. The SKSP server and the benchmarks can be accessed at http://sparks.informatics.iupui.edu PMID:17932927

  18. 49 CFR Appendix B to Part 192 - Qualification of Pipe

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...Specification for Electric-Fusion-Welded Pipe for...Specification for Electric-Fusion-Welded Steel Pipe...Specification for Carbon and Alloy Steel Pipe, Electric-Fusion-Welded for High...length of pipe must be cold bent...

  19. 49 CFR Appendix B to Part 192 - Qualification of Pipe

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...Specification for Electric-Fusion-Welded Pipe for...Specification for Electric-Fusion-Welded Steel Pipe...Specification for Carbon and Alloy Steel Pipe, Electric-Fusion-Welded for High...length of pipe must be cold bent...

  20. 49 CFR Appendix B to Part 192 - Qualification of Pipe

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...Specification for Electric-Fusion-Welded Pipe for...Specification for Electric-Fusion-Welded Steel Pipe...Specification for Carbon and Alloy Steel Pipe, Electric-Fusion-Welded for High...length of pipe must be cold bent...