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1

Piping benchmark problems for the Westinghouse AP600 Standardized Plant  

SciTech Connect

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.

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

1997-01-01

2

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

SciTech Connect

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.

Bezler, P.; DeGrassi, G.; Braverman, J.; Wang, Y.K. [Brookhaven National Lab., Upton, NY (United States)] [Brookhaven National Lab., Upton, NY (United States)

1994-07-01

3

Overview of cooperative international piping benchmark analyses  

SciTech Connect

This paper presents an overview of an effort initiated in 1976 by the International Working Group on Fast Reactors (IWGFR) of the International Atomic Energy Agency (IAEA) to evaluate detailed and simplified inelastic analysis methods for piping systems with particular emphasis on piping bends. The procedure was to collect from participating member IAEA countries descriptions of tests and test results for piping systems or bends (with emphasis on high temperature inelastic tests), to compile, evaluate, and issue a selected number of these problems for analysis, and to compile and make a preliminary evaluation of the analyses results. Of the problem descriptions submitted three were selected to be used: a 90/sup 0/-elbow at 600/sup 0/C with an in-plane transverse force; a 90/sup 0/-elbow with an in-plane moment; and a 180/sup 0/-elbow at room temperature with a reversed, cyclic, in-plane transverse force. A variety of both detailed and simplified analysis solutions were obtained. A brief comparative assessment of the analyses is contained in this paper. 15 figures.

McAfee, W.J.

1982-01-01

4

MCNP: Neutron benchmark problems  

SciTech Connect

The recent widespread and increased use of radiation transport codes has produced greater user and institutional demand for assurances that such codes give correct results. Responding to these requirements for code validation, the general purpose Monte Carlo transport code MCNP has been tested on criticality, pulsed sphere, and shielding neutron problem families. Results for each were compared to experimental data. MCNP successfully predicted the experimental results of all three families within the expected data and statistical uncertainties. These successful predictions demonstrate that MCNP can successfully model a broad spectrum of neutron transport problems. 18 refs., 27 figs., 4 tabs.

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

1991-11-01

5

Monte Carlo photon benchmark problems  

SciTech Connect

Photon benchmark calculations have been performed to validate the MCNP Monte Carlo computer code. These are compared to both the COG Monte Carlo computer code and either experimental or analytic results. The calculated solutions indicate that the Monte Carlo method, and MCNP and COG in particular, can accurately model a wide range of physical problems.

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

1991-01-01

6

Monte Carlo photon benchmark problems  

SciTech Connect

Photon benchmark calculations have been performed to validate the MCNP Monte Carlo computer code. These are compared to both the COG Monte Carlo computer code and either experimental or analytic results. The calculated solutions indicate that the Monte Carlo method, and MCNP and COG in particular, can accurately model a wide range of physical problems. 8 refs., 5 figs.

Whalen, D.J. (Brigham Young Univ., Provo, UT (USA)); Hollowell, D.E.; Hendricks, J.S. (Los Alamos National Lab., NM (USA))

1990-01-01

7

MCNP: Photon benchmark problems  

SciTech Connect

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.

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

1991-09-01

8

Computational evaluation of two reactor benchmark problems  

E-print Network

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...

Cowan, James Anthony

2012-06-07

9

Benchmark problems in computational aeroacoustics  

NASA Technical Reports Server (NTRS)

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).

Porter-Locklear, Freda

1994-01-01

10

Benchmark Problems for Spacecraft Formation Flying Missions  

NASA Technical Reports Server (NTRS)

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.

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

2003-01-01

11

Dependability Benchmarking & Prediction: A Grand Challenge Technology Problem  

E-print Network

Dependability Benchmarking & Prediction: A Grand Challenge Technology Problem Abstract We propose requirements. But, eager adoption of less-than-dependable technology in effectively critical roles will happen the grand challenge problem of dependability benchmarking and prediction for real-time mission

Koopman, Philip

12

3D Benchmark on Discretization Schemes for Anisotropic Diffusion Problems  

E-print Network

3D Benchmark on Discretization Schemes for Anisotropic Diffusion Problems on General Grids Robert and heterogeneous diffusion problems, associated with general, possibly non-conforming, 3D grids, were proposed-conforming meshes, 3D benchmark. MSC2010: 65N08, 65N30, 65Y20, 76S05 Robert Eymard Universit´e Paris-Est, France, e

Paris-Sud XI, Université de

13

Simplified two and three dimensional HTTR benchmark problems  

SciTech Connect

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.

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

2011-05-01

14

Numerical results for the WFNDEC 2012 eddy current benchmark problem  

NASA Astrophysics Data System (ADS)

We present numerical results for the World Federation of NDE Centers (WFNDEC) 2012 eddy current benchmark problem obtained with a commercial FEM package (Comsol Multiphysics). The measurements of the benchmark problem consist of coil impedance values acquired when an inspection probe coil is moved inside an Inconel tube along an axial through-wall notch. The simulation runs smoothly with minimal user interference (default settings used for mesh and solver) and agreement between numerical and experimental results is excellent for all five inspection frequencies. Comments are made for the pros and cons of FEM and also some good practice rules are presented when using such numerical tools.

Theodoulidis, T. P.; Martinos, J.; Poulakis, N.

2013-01-01

15

System identification and control synthesis for a benchmark problem  

Microsoft Academic Search

In this paper we apply the integrated system identification\\/H? control synthesis approach to the IFAC 1993 benchmark problem using the minimal amount of process information revealed. The resulting performance compares favorably to those using time-invariant control design techniques, and achieves prescribed performance for small and medium levels of plant uncertainties. For strong plant variations, the performance is inferior to most

Ka-Lun Tung; Yeung Yam

1998-01-01

16

Fourth Computational Aeroacoustics (CAA) Workshop on Benchmark Problems  

NASA Technical Reports Server (NTRS)

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.

Dahl, Milo D. (Editor)

2004-01-01

17

The rotating movement of three immiscible fluids - A benchmark problem  

USGS Publications Warehouse

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.

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

2004-01-01

18

Summary of results for the uranium benchmark problem of the ANS Ad Hoc Committee on Reactor Physics Benchmarks  

SciTech Connect

This paper presents a summary of the results obtained by all of the contributors to the Uranium Benchmark Problem of the ANS Ad hoc Committee on Reactor Physics Benchmarks. The benchmark problem was based on critical experiments which mocked-up lattices typical of PWRs. Three separate cases constituted the benchmark problem. These included a uniform lattice, an assembly-type lattice with water holes and an assembly-type lattice with pyrex rods. Calculated results were obtained from eighteen separate organizations from all over the world. Some organizations submitted more than one set of results based on different calculational methods and cross section data. Many of the most widely used assembly physics and core analysis computer codes and neutron cross section data libraries were applied by the contributors.

Parish, T.A. [Texas A and M Univ., College Station, TX (United States). Nuclear Engineering Dept.; Mosteller, R.D. [Los Alamos National Lab., NM (United States); Diamond, D.J. [Brookhaven National Lab., Upton, NY (United States); Gehin, J.C. [Oak Ridge National Lab., TN (United States)

1998-12-31

19

The Problem with the Linpack Benchmark Matrix Generator June 28, 2008  

E-print Network

The Problem with the Linpack Benchmark Matrix Generator June 28, 2008 Jack Dongarra Department Abstract: We characterize the matrix sizes for which the Linpack Benchmark matrix generator constructs rules for running the benchmark state that the supplied matrix generator, which uses a pseudo­ random

Dongarra, Jack

20

Robustness of solutions to a benchmark control problem  

NASA Technical Reports Server (NTRS)

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.

Stengel, Robert F.; Marrison, Christopher I.

1992-01-01

21

Pericles and Attila results for the C5G7 MOX benchmark problems  

SciTech Connect

Recently the Nuclear Energy Agency has published a new benchmark entitled, 'C5G7 MOX Benchmark.' This benchmark is to test the ability of current transport codes to treat reactor core problems without spatial homogenization. The benchmark includes both a two- and three-dimensional problem. We have calculated results for these benchmark problems with our Pericles and Attila codes. Pericles is a one-,two-, and three-dimensional unstructured grid discrete-ordinates code and was used for the twodimensional benchmark problem. Attila is a three-dimensional unstructured tetrahedral mesh discrete-ordinate code and was used for the three-dimensional problem. Both codes use discontinuous finite element spatial differencing. Both codes use diffusion synthetic acceleration (DSA) for accelerating the inner iterations.

Wareing, T. A. (Todd A.); McGhee, J. M. (John M.)

2002-01-01

22

Simple Analytical U-Tube Benchmarks Appropriate for Testing of Pipe-Network Computer Codes  

SciTech Connect

Partially heated U-tube configurations are characteristic idealizations for the so called building condensers of future nuclear reactors with passive safety systems. In this paper three simple cases of natural circulation problems are analyzed and analytical solutions are generated. This solutions are recommended for validation of pipe network computer codes. As an example the procedure is demonstrated for the IVA computer code. The usefulness of the obtained solutions is demonstrated discussing the inherent safety behavior of the building condenser of the Framatome ANP SWR 1000 power plant being under development. (authors)

Kolev, N.I. [Framatome ANP GmbH, PO Box 3220, Erlangen, 91050 (Germany)

2002-07-01

23

PARTISN results for the C5G7 MOX benchmark problems  

Microsoft Academic Search

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

J. A. Dahl; Raymond E. Alcouffe

2002-01-01

24

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

E-print Network

is given by Algorithm 1 in [BRE 05b]. By usual hybridization known from mixed finite elements, system [2Benchmark 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

Cirpka, Olaf Arie

25

Structural control benchmark problem: Phase II-Nonlinear smart base-isolated building subjected to near-fault earthquakes  

Microsoft Academic Search

SUMMARY Many branches of engineering, mathematics, and sciences, have relied on benchmark problems as a standard means to compare different solution techniques. Since 1996, the ASCE Structural Control and Monitoring Committee and Task Group on Benchmark Problems, the U.S. Panel on structural control, and IASCM have developed a series of benchmark control problems that offer a set of carefully modeled

Satish Nagarajaiah; Sriram Narasimhan; Erik Johnson

2008-01-01

26

Identification of significant problems related to light water reactor piping systems  

SciTech Connect

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.

None

1980-07-01

27

Higher-order finite element discretizations in a benchmark problem for incompressible flows  

NASA Astrophysics Data System (ADS)

We present a numerical study of several finite element discretizations applied to a benchmark problem for the two-dimensional steady state incompressible Navier-Stokes equations defined in Schfer and Turek (The benchmark problem Flow around a cylinder. In Flow Simulation with High-Performance Computers II. Notes on Numerical Fluid Mechanics, vol. 52, Hirschel EH (ed.). Vieweg: Wiesbaden, 1996; 547-566). The discretizations are compared with respect to the accuracy of the computed benchmark parameters. Higher-order isoparametric finite element discretizations turned out to be by far the most accurate. The discrete systems obtained with higher-order discretizations are solved with a modified coupled multigrid method whose behaviour within the benchmark problem is also studied numerically. Copyright

John, Volker; Matthies, Gunar

2001-12-01

28

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

SciTech Connect

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.

Brantley, P S; Palmer, T S

2009-02-24

29

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

SciTech Connect

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.

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

2001-03-22

30

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

PubMed Central

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

Lovaglio, Pietro Giorgio

2012-01-01

31

Large Core Code Evaluation Working Group Benchmark Problem Four: neutronics and burnup analysis of a large heterogeneous fast reactor. Part 1. Analysis of benchmark results. [LMFBR  

Microsoft Academic Search

The Large Core Code Evaluation Working Group Benchmark Problem Four was specified to provide a stringent test of the current methods which are used in the nuclear design and analyses process. The benchmark specifications provided a base for performing detailed burnup calculations over the first two irradiation cycles for a large heterogeneous fast reactor. Particular emphasis was placed on the

C. L. Cowan; R. Protsik; J. W. Lewellen

1984-01-01

32

Maintenance scheduling problems as benchmarks for constraint algorithms  

Microsoft Academic Search

The paper focuses on evaluating constraint satisfaction search algorithms on application based random problem instances. The\\u000a application we use is a well-studied problem in the electric power industry: optimally scheduling preventive maintenance of\\u000a power generating units within a power plant. We show how these scheduling problems can be cast as constraint satisfaction\\u000a problems and used to define the structure of

Daniel Frost; Rina Dechter

1999-01-01

33

Energy Storage Benchmark Problems Daniel F. Salas1,3  

E-print Network

& Biological Engineering 2 Department of Operations Research & Financial Engineering 3 Princeton Laboratory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 1 Purpose In this document, we lay out the model for a general energy storage control problem of these problems is included in the accompanying .zip file. This is meant to be a collection of problems

Powell, Warren B.

34

Benchmarking Problems Used in Second Year Level Organic Chemistry Instruction  

ERIC Educational Resources Information Center

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

Raker, Jeffrey R.; Towns, Marcy H.

2010-01-01

35

Sonic limitations and startup problems of heat pipes  

NASA Technical Reports Server (NTRS)

Introduction of small amounts of inert, noncombustible gas aids startup in certain types of heat pipes. When the heat pipe is closely coupled to the heat sink, the startup system must be designed to bring the heat sink on-line slowly.

Deverall, J. E.; Kemme, J. E.; Florschuetz, L. W.

1972-01-01

36

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

NASA Technical Reports Server (NTRS)

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.

Lin, Wen H.; Chan, Daniel C.

1997-01-01

37

Three-index Model for Westenberger-Kallrath Benchmark Scheduling Problem  

NASA Astrophysics Data System (ADS)

Short-term scheduling of batch operations has become an important research area in the last two decades. Recently Shaik and Floudas (2009) proposed a novel unified model for short-term scheduling using unit-specific event based continuous time representation employing three-index binary and continuous variables. In this work, we extend this three index model to solve a challenging benchmark problem from the scheduling literature that covers most of the features contributing to the complexity of batch process scheduling in industry. In order to implement the problem, new sets of constraints and modifications are incorporated into the three-index model. The different demand instances of the benchmark problem have been solved using the developed model and the results are compared with the literature to demonstrate the effectiveness of the proposed three-index model.

Vooradi, Ramsagar; Shaik, Munawar A.; Gupta, Nikhil M.

2010-10-01

38

Clad piping - a novel approach for solving nuclear plant service water and erosion-corrosion problems  

SciTech Connect

This paper discusses the application of clad piping components to solve various nuclear plant corrosion problems, such as service water system corrosion and feedwater/condensate/steam erosion-corrosion. This approach uses a carbon steel piping component which has a metallurgically bonded alloy cladding on the ID. Different alloys are available as cladding, from stainless steels to Inconel 625, so that a specific alloy can be selected based on the service requirements. Clad piping components represent a novel approach, as they provide a mechanism to utilize resistant alloys to solve corrosion problems without affecting the plant design. Clad piping products are designed such that the carbon steel backing acts as the pressure boundary and the cladding the corrosion allowance. By selecting the proper carbon steel backing, the clad product can be engineered to allow {open_quotes}like-for-like{close_quotes} component replacement. The wall thickness, weight and stiffness of the piping would remain essentially the same. The thermal expansion coefficient of the bulk piping also remains the same. Thus, the piping design and layout is wholly unaffected, with no structural reanalysis being required. This paper discusses two applications where clad piping products are being applied for solving nuclear power plant corrosion problems. The first is in solving steam/condensate/feedwater erosion-corrosion. The second application is the utilization of Inconel 625 clad piping products for solving service water system corrosion. Clad piping products solve these problems while improving plant operation and performance by basically providing the benefits of the alloy without any of the accompanying disadvantages of redesign.

Chakravarti, B. [NUTECH Engineers, Inc., Westmont, IL (United States)

1992-12-31

39

PARTISN results for the C5G7 MOX benchmark problems  

SciTech Connect

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).

Dahl, J. A. (Jon A.); Alcouffe, Raymond E.

2002-01-01

40

TOPS nodal code solutions for the OECD/PBMR-400 benchmark problem  

SciTech Connect

This paper provides the solution of the OECD/PBMR-400 benchmark problem by the TOPS code based on the Analytic Function Expansion Nodal (AFEN) method in 3-D cylindrical geometry. The paper is focused on the multi-group methodology, two methods (partial current translation and AFEN formulation) of treating the void regions, and comparison of the their results. We also suggest a modified benchmark problem, which does not have void regions where special treatments are required, to be used to verify the calculational methods in cylindrical geometry. The results indicate that the effect of void regions is significant and that the method how to treat the voids in computation is important. (authors)

Lee, J.; Lee, J. H.; Yoo, H. J.; Lee, G. S.; Cho, N. Z. [Korea Advanced Inst. of Science and Technology, 373-1 Kusong-dong, Yusong-gu, Daejeon (Korea, Republic of)

2006-07-01

41

3D radiation transport benchmark problems and results for simple geometries with void region  

Microsoft Academic Search

Three-dimensional (3D) transport benchmark problems for simple geometries with void region were proposed at the OECD\\/NEA in order to check the accuracy of deterministic 3D transport programs. The exact total fluxes by the analytical method are given for the pure absorber cases, and Monte Carlo values are given for the 50% scattering cases as the reference values. The total fluxes

Yasunobu Nagaya; Naoki Sugimura

2001-01-01

42

pipes  

Microsoft Academic Search

The aim of this paper is to present a kinetic numerical scheme for the computations of transient pressurised flows in closed water pipes. Firstly, we detail the mathematical model written as a conservative hyperbolic partial differentiel system of equations, and then we recall how to obtain the corresponding kinetic formulation. Then we build the kinetic scheme ensuring an upwinding of

C. Bourdarias; S. Gerbi

43

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

NASA Technical Reports Server (NTRS)

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.

Envia, Edmane

2004-01-01

44

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

PubMed Central

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

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

2014-01-01

45

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

NASA Technical Reports Server (NTRS)

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.

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

1995-01-01

46

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

NASA Technical Reports Server (NTRS)

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.

Choudhari, Meelan M.; Yamamoto, Kazuomi

2012-01-01

47

On the inverse problems for the coupled continuum pipe flow model for flows in karst aquifers  

NASA Astrophysics Data System (ADS)

We investigate two inverse problems for the coupled continuum pipe flow (CCPF) model which describes fluid flows in karst aquifers. After generalizing the well posedness of the forward problem to the anisotropic exchange rate case which is a space-dependent variable, we present the uniqueness of this parameter by measuring the Cauchy data. The uniqueness of the geometry of the conduit by the Cauchy data is verified as well. These results enhance the practicality of the CCPF model.

Lu, Shuai; Chen, Nan; Hu, Bang; Cheng, Jin

2012-06-01

48

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

SciTech Connect

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.

Winters, W.S.

1985-10-01

49

C5 Benchmark Problem with Discrete Ordinate Radiation Transport Code DENOVO  

SciTech Connect

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.

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

2011-01-01

50

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

NASA Technical Reports Server (NTRS)

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.

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

1995-01-01

51

Helmholtz and parabolic equation solutions to a benchmark problem in ocean acoustics.  

PubMed

The Helmholtz equation (HE) describes wave propagation in applications such as acoustics and electromagnetics. For realistic problems, solving the HE is often too expensive. Instead, approximations like the parabolic wave equation (PE) are used. For low-frequency shallow-water environments, one persistent problem is to assess the accuracy of the PE model. In this work, a recently developed HE solver that can handle a smoothly varying bathymetry, variable material properties, and layered materials, is used for an investigation of the errors in PE solutions. In the HE solver, a preconditioned Krylov subspace method is applied to the discretized equations. The preconditioner combines domain decomposition and fast transform techniques. A benchmark problem with upslope-downslope propagation over a penetrable lossy seamount is solved. The numerical experiments show that, for the same bathymetry, a soft and slow bottom gives very similar HE and PE solutions, whereas the PE model is far from accurate for a hard and fast bottom. A first attempt to estimate the error is made by computing the relative deviation from the energy balance for the PE solution. This measure gives an indication of the magnitude of the error, but cannot be used as a strict error bound. PMID:12765364

Larsson, Elisabeth; Abrahamsson, Leif

2003-05-01

52

Higher order finite element methods and multigrid solvers in a benchmark problem for the 3D Navier-Stokes equations  

NASA Astrophysics Data System (ADS)

This paper presents a numerical study of the 3D flow around a cylinder which was defined as a benchmark problem for the steady state Navier-Stokes equations within the DFG high-priority research program flow simulation with high-performance computers by Schafer and Turek (Vol. 52, Vieweg: Braunschweig, 1996). The first part of the study is a comparison of several finite element discretizations with respect to the accuracy of the computed benchmark parameters. It turns out that boundary fitted higher order finite element methods are in general most accurate. Our numerical study improves the hitherto existing reference values for the benchmark parameters considerably. The second part of the study deals with efficient and robust solvers for the discrete saddle point problems. All considered solvers are based on coupled multigrid methods. The flexible GMRES method with a multiple discretization multigrid method proves to be the best solver.

John, Volker

2002-10-01

53

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

NASA Astrophysics Data System (ADS)

The problems of vortex shedding from bluff, flexible structures in steady currents and the resulting vortex excited oscillations are investigated. The effects of flow nonuniformities, surface roughness of the cylinder, and inclination to the incident flow are considered in addition to the case of a smooth cylinder 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.

Griffin, O. M.

1980-03-01

54

Benchmark problem for beam pointing control of phased array radar against maneuvering targets in the presence of ECM and false alarms  

Microsoft Academic Search

This paper extends an earlier benchmark problem for beam pointing control of a phased array radar to include the effects of false alarms and ECM. Multiple waveforms are included in the benchmark problem so that the radar energy can be coordinated with the tracking algorithm. The ECM includes a standoff jammer broadcasting wideband noise and targets attempting range gate pull

W. D. Blair; Watson G. L. Gentry; G. L. Gentry; S. A. Hoffman

1995-01-01

55

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

NASA Astrophysics Data System (ADS)

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 destructive 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 cylinder 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 the 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.

Griffin, O. M.

1980-03-01

56

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

NASA Astrophysics Data System (ADS)

The objective of this paper 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 Ocean Thermal Energy Conversion cold water pipe. Practical design calculations are given as examples throughout the various sections of the report. This paper 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 cylinder 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.

Griffin, O. M.

57

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

SciTech Connect

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.

Krishnamurthy, C. V.; Shankar, M.; Vardhan, J. Vishnu [Centre for NonDestructive Evaluation, Indian Institute of Technology, Chennai, India 600 036 (India); Balasubramaniam, Krishnan [Department of Mechanical Engineering, Indian Institute of Technology, Chennai, India 600 036 (India)

2006-03-06

58

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

NASA Technical Reports Server (NTRS)

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.

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

2011-01-01

59

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

SciTech Connect

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.

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

2011-06-01

60

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

SciTech Connect

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.

Wilson, L.T. [Naval Surface Warfare Center, Dahlgren, VA (United States); Hertel, E. [Sandia National Labs., Albuquerque, NM (United States); Schwalbe, L.; Wingate, C. [Los Alamos National Lab., NM (United States)

1998-02-01

61

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

USGS Publications Warehouse

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.

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

1997-01-01

62

Finite-element\\/progressive-lattice-sampling response surface methodology and application to benchmark probability quantification problems  

Microsoft Academic Search

Optimal response surface construction is being investigated as part of Sandia discretionary (LDRD) research into Analytic Nondeterministic Methods. The goal is to achieve an adequate representation of system behavior over the relevant parameter space of a problem with a minimum of computational and user effort. This is important in global optimization and in estimation of system probabilistic response, which are

V. J. Romero; S. D. Bankston

1998-01-01

63

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 ...

64

Finite-element/progressive-lattice-sampling response surface methodology and application to benchmark probability quantification problems  

SciTech Connect

Optimal response surface construction is being investigated as part of Sandia discretionary (LDRD) research into Analytic Nondeterministic Methods. The goal is to achieve an adequate representation of system behavior over the relevant parameter space of a problem with a minimum of computational and user effort. This is important in global optimization and in estimation of system probabilistic response, which are both made more viable by replacing large complex computer models with fast-running accurate and noiseless approximations. A Finite Element/Lattice Sampling (FE/LS) methodology for constructing progressively refined finite element response surfaces that reuse previous generations of samples is described here. Similar finite element implementations can be extended to N-dimensional problems and/or random fields and applied to other types of structured sampling paradigms, such as classical experimental design and Gauss, Lobatto, and Patterson sampling. Here the FE/LS model is applied in a ``decoupled`` Monte Carlo analysis of two sets of probability quantification test problems. The analytic test problems, spanning a large range of probabilities and very demanding failure region geometries, constitute a good testbed for comparing the performance of various nondeterministic analysis methods. In results here, FE/LS decoupled Monte Carlo analysis required orders of magnitude less computer time than direct Monte Carlo analysis, with no appreciable loss of accuracy. Thus, when arriving at probabilities or distributions by Monte Carlo, it appears to be more efficient to expend computer-model function evaluations on building a FE/LS response surface than to expend them in direct Monte Carlo sampling.

Romero, V.J.; Bankston, S.D.

1998-03-01

65

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

SciTech Connect

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.

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

1992-01-01

66

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

ERIC Educational Resources Information Center

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.

Engel, Renata S.; And Others

1996-01-01

67

Analytical solution of the Brazier problem for thin-wall pipes with initial cross-sectional shape imperfection in the case of action of pressure  

Microsoft Academic Search

An analytical method is proposed for the solution of geometrically nonlinear Brazier problem for thin-mall pipes with initial\\u000a cross-sectional shape imperfection in the case of action of pressure. Geometrical equations relating displacement components\\u000a to strains and equilibrium equations taking into account change in the curvature of pipe cross section and axis have been\\u000a derived. A solution in a first approximation

I. V. Orynyak; S. A. Radchenko

2008-01-01

68

A benchmark-problem specification and calculation using SENSIBL, a one- and two-dimensional sensitivity and uncertainty analysis code of the AARE system  

SciTech Connect

The lack of suitable benchmark problems makes it difficult to test sensitivity codes with a covariance library. A benchmark problem has therefore been defined for one- and two-dimensional sensitivity and uncertainity analysis codes and code systems. The problem, representative of a fusion reactor blanket, has a simple, three-zone )tau)-z geometry containing a D-T fusion neutron source distributed in a central void region surrounded by a thick /sup 6/LiH annulus. The response of interest is the /sup 6/Li tritium production per source neutron, T/sub 6/. The calculation has been performed with SENSIBL using other codes from the AARE code system as a test of both SENSIBL and the linked, modular system. The caluclation was performed using the code system in the standard manner with a covariance data library in the COVFILS-2 format but modified to contain specifically tailored covariance data for H and /sup 6/Li (Path A). The calculation was also performed by a second method which uses specially perturbed H and Li cross sections (Path B). This method bypasses SENSIBL and allows a hand calculation of the benchmark T/sub 6/ uncertainties. The results of Path A and Path B were total uncertainties in T/sub 6/ of 0.21% and 0.19%, respectively. The closeness of the results for this challenging test gives confidence that SENSIBL and the AARE system will perform well for realistic sensitivity and uncertainty analyses

Muir, D.W.; Davidson, J.W.; Dudziak, D.J.; Davierwalla, D.M.; Higgs, C.E.; Stepanek, J.

1988-01-01

69

Benchmarking--Measuring and Comparing for Continuous Improvement.  

ERIC Educational Resources Information Center

Discussion of benchmarking focuses on the use of internal and external benchmarking by special librarians. Highlights include defining types of benchmarking; historical development; benefits, including efficiency, improved performance, increased competitiveness, and better decision making; problems, including inappropriate adaptation; developing a

Henczel, Sue

2002-01-01

70

The evaluation of erosion\\/corrosion problems of carbon steel piping in Taiwan PWR nuclear power plant  

Microsoft Academic Search

Taiwan Pressurized Water Reactor (PWR), Maanshan nuclear power plant Units 1 and 2 implemented measurements of the wall thinning of the carbon steel piping under the request of regulation authority to prevent the events due to erosion\\/corrosion since 1989. At first, the licensee established the comprehensive inspection program by itself. Over 2000 components were inspected per unit and 300500 pipe

Kuen Ting; Yin Pang Ma

1999-01-01

71

Limitations of Community College Benchmarking and Benchmarks  

ERIC Educational Resources Information Center

This chapter distinguishes between benchmarks and benchmarking, describes a number of data and cultural limitations to benchmarking projects, and suggests that external demands for accountability are the dominant reason for growing interest in benchmarking among community colleges.

Bers, Trudy H.

2006-01-01

72

Analysis of the OECD Main Steam Line Break Benchmark Problem Using the Refined Core Thermal-Hydraulic Nodalization Feature of the MARS/MASTER Code  

SciTech Connect

The refined core thermal-hydraulics (T-H) nodalization feature of the MARS/MASTER code is used to generate a high-fidelity solution to the OECD main steam line break benchmark problem and to investigate the effects of core T-H nodalization. The MARS/MASTER coupling scheme is introduced first that enables efficient refined node core T-H calculations via the COBRA-III module. The base solution is generated using a fine T-H nodalization consisting of fuel assembly-sized radial nodes. Sensitivity studies are performed on core T-H nodalization to examine the impacts on core reactivity, power distribution, and transient behavior. The results indicate that the error in the peak local power can be very large (up to 25%) with a coarse T-H nodalization because of the inability to incorporate detailed thermal feedback. A demonstrative departure from nucleate boiling (DNB) calculation shows no occurrence of DNB in this problem.

Joo, Han Gyu; Jeong, Jae-Jun; Cho, Byung-Oh; Lee, Won Jae; Zee, Sung Quun [Korea Atomic Energy Research Institute (Korea, Republic of)

2003-05-15

73

Comparison of Whole-Domain and Sequential Algorithms for Function Specification Method in the Inverse Heat Transfer Problem of Laminar Convective Pipe Flow  

Microsoft Academic Search

This article compares the application of the whole-domain function specification method (WDFSM) and the sequential function specification method (SFSM) to the inverse problem of transient conjugate heat transfer of laminar forced convection in a circular pipe. The two inverse methods are used to estimate the time-varying inlet temperature and the outer-wall heat flux simultaneously on the basis of temperature measurements

Cha'o.-Kuang Chen; Li-Wen Wu; Yue-Tzu Yang

2006-01-01

74

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

NASA Technical Reports Server (NTRS)

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.

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

2000-01-01

75

A stabilized mixed finite element method for shear-rate dependent non-Newtonian fluids: 3D benchmark problems and application to blood flow in bifurcating arteries  

NASA Astrophysics Data System (ADS)

This paper presents a stabilized mixed finite element method for shear-rate dependent fluids. The nonlinear viscosity field is a function of the shear-rate and varies uniformly in space and in time. The stabilized form is developed via application of Variational Multiscale (VMS) framework to the underlying generalized Navier-Stokes equation. Linear and quadratic tetrahedral and hexahedral elements are employed with equal-order interpolations for the velocity and pressure fields. A variety of benchmark problems are solved to assess the stability and accuracy properties of the resulting method. The method is then applied to non-Newtonian shear-rate dependent flows in bifurcating artery geometry, and significant non-Newtonian fluid effects are observed. A comparative study of the proposed method shows that the additional computational costs due to the nonlinear shear-rate dependent viscosity are only ten percent more than the computational cost for a Newtonian model.

Kwack, JaeHyuk; Masud, Arif

2014-04-01

76

Testing (Validating?) Cross Sections with ICSBEP Benchmarks  

SciTech Connect

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).

Kahler, Albert C. III [Los Alamos National Laboratory

2012-06-28

77

Miniature Heat Pipes  

NASA Technical Reports Server (NTRS)

Small Business Innovation Research contracts from Goddard Space Flight Center to Thermacore Inc. have fostered the company work on devices tagged "heat pipes" for space application. To control the extreme temperature ranges in space, heat pipes are important to spacecraft. The problem was to maintain an 8-watt central processing unit (CPU) at less than 90 C in a notebook computer using no power, with very little space available and without using forced convection. Thermacore's answer was in the design of a powder metal wick that transfers CPU heat from a tightly confined spot to an area near available air flow. The heat pipe technology permits a notebook computer to be operated in any position without loss of performance. Miniature heat pipe technology has successfully been applied, such as in Pentium Processor notebook computers. The company expects its heat pipes to accommodate desktop computers as well. Cellular phones, camcorders, and other hand-held electronics are forsible applications for heat pipes.

1997-01-01

78

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

E-print Network

associated with model validation and verification. * Corresponding author. Tel.: +1-334-844-6268; fax: +1 for the simulation of density-dependent, variably saturated flow processes are presented here. The model is tested of this communi- cation to enter into this philosophical discussion, the inherent problems with model verification

Clement, Prabhakar

79

Practical piping handbook  

SciTech Connect

A reference book on pipes, pipe fitting, and pipe treatment in the petroleum and natural gas industries is presented. The contents include: standard piping terminology; piping codes and standards; pipe manufacturing sizes; metallic piping; non-metallic piping; lined and coated piping systems; pipe tracing and jacketing; fittings and flanges; piping connections; valves; pipe expansion devices; flexible piping; piping specialties; pipe supports and restraints; insulation for piping; shop fabrication of piping; field installation of piping; construction tools and equipment; nondestructive and destructive testing; pipe cleaning; and comparative piping costs. (JMT)

Mendel, O.

1981-01-01

80

Hg supply piping simulation Stony Brook University  

E-print Network

Hg supply piping simulation (No MHD) Stony Brook University Yan Zhan Prof. Foluso Ladeinde July 2nd, 2010 #12;Outline · Hg supply piping in Muon Collider · Turbulence models for bend pipe flow · Problems need studying · Arrangements in the near future #12;Outline · Hg supply piping in Muon Collider ­ Hg

McDonald, Kirk

81

A study of circumferentially-heated and block-heated heat pipes. I - Experimental analysis and generalized analytical prediction of capillary limits. II - Three-dimensional numerical modeling as a conjugate problem  

NASA Technical Reports Server (NTRS)

The wall and centerline vapor temperatures and heat output are determined experimentally for a low-temperature copper-water heat pipe under uniform circumferential heating and block heating. The time required to reach a vapor temperature of 60 C from an initial ambient temperature of 21 C is determined for both modes of heating. The experimental capillary limit of the heat pipe is compared to the generalized capillary limits for block-heated pipes over a range of vapor temperatures. A three-dimensional numerical model is then developed for determining the temperature, pressure, and velocity distributions in the entire domain of a circumferentially heated and a block-heated pipe. The problem is formulated as a conjugate problem, without the assumption of a uniform vapor temperature. The predictions of the model are found to be in good agreement with the experimental data.

Schmalhofer, Joseph; Faghri, Amir

1993-01-01

82

Pipe Dreams.  

ERIC Educational Resources Information Center

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)

Milshtein, Amy

2002-01-01

83

Benchmark Glaciers  

NSDL National Science Digital Library

The United States Geological Survey (USGS) operates a long-term "benchmark" glacier program to intensively monitor climate, glacier motion, glacier mass balance, glacier geometry, and stream runoff at a few select sites. The data collected are used to understand glacier-related hydrologic processes and improve the quantitative prediction of water resources, glacier-related hazards, and the consequences of climate change. This page presents some of the balance, runoff, and temperature data for three glaciers: Gulkana, South Cascade and Wolverine. Reports for each of these glaciers uses the collected data to draw many conclusions. There is also a section with common questions and myths about glaciers.

84

Benchmarking Query Execution Robustness  

NASA Astrophysics Data System (ADS)

Benchmarks that focus on running queries on a well-tuned database system ignore a long-standing problem: adverse runtime conditions can cause database system performance to vary widely and unexpectedly. When the query execution engine does not exhibit resilience to these adverse conditions, addressing the resultant performance problems can contribute significantly to the total cost of ownership for a database system in over-provisioning, lost efficiency, and increased human administrative costs. For example, focused human effort may be needed to manually invoke workload management actions or fine-tune the optimization of specific queries.

Wiener, Janet L.; Kuno, Harumi; Graefe, Goetz

85

Unstructured Adaptive (UA) NAS Parallel Benchmark. Version 1.0  

NASA Technical Reports Server (NTRS)

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.

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

2004-01-01

86

Benchmarking in Student Affairs.  

ERIC Educational Resources Information Center

Discusses the use of benchmarking in student affairs, focusing on issues related to student housing. Provides examples of how benchmarking has influenced administrative practice at many institutions. (EV)

Mosier, Robert E.; Schwarzmueller, Gary J.

2002-01-01

87

BENCHMARK TESTING A.1 Benchmark Testing Design  

E-print Network

of various degrees of speci city (e.g., Arti cial Intelligence vs. Natural Language Processing) and di erent173 Appendix A BENCHMARK TESTING A.1 Benchmark Testing Design We rst performed a benchmark testing, were: (1-term: Natural Language Processing), (2-terms: Group Decision Support Systems, Collaboration

88

BENCHMARK TESTING A.1 Benchmark Testing Design  

E-print Network

consisted of terms of various degrees of specificity (e.g., Artificial Intelligence vs. Natural Language173 Appendix A BENCHMARK TESTING A.1 Benchmark Testing Design We first performed a benchmark in the computing area, were: (1­term: Natural Language Processing), (2­terms: Group Decision Support Systems

89

Heat Pipes  

NASA Technical Reports Server (NTRS)

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.

1991-01-01

90

Radiation Detection Computational Benchmark Scenarios  

SciTech Connect

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.

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

2013-09-24

91

Benchmarking the Connection Machine  

SciTech Connect

The purpose of this memo is to present the results of work done recently on the Connection Machine during a one-week visit by the authors to Thinking Machines Corporation. The main objectives of the trip were to benchmark the Connection Machine and to assess the software environment, in order to determine the suitability of the Connection Machine for solving computationally-intensive problems and to compare the Connection Machine with other highly-parallel computers. This report presents preliminary results, and describes the computer architecture.

Baillie, C.; Felten, E.; Walker, D.

1987-01-01

92

Benchmarking and Performance Measurement.  

ERIC Educational Resources Information Center

This paper defines benchmarking and its relationship to quality management, describes a project which applied the technique in a library context, and explores the relationship between performance measurement and benchmarking. Numerous benchmarking methods contain similar elements: deciding what to benchmark; identifying partners; gathering

Town, J. Stephen

93

Perspective: Selected benchmarks from commercial CFD codes  

Microsoft Academic Search

This paper summarizes the results of a series of five benchmark simulations which were completed using commercial Computational Fluid Dynamics (CFD) codes. These simulations were performed by the vendors themselves, and then reported by them in ASME`s CFD Triathlon Forum and CFD Biathlon Forum. The first group of benchmarks consisted of three laminar flow problems. These were the steady, two-dimensional

C. J. Freitas

1995-01-01

94

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

NASA Astrophysics Data System (ADS)

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.

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

2011-01-01

95

Heat pipe dynamic behavior  

NASA Technical Reports Server (NTRS)

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.

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

1988-01-01

96

Silicon Heat Pipe Array  

NASA Technical Reports Server (NTRS)

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.

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

2013-01-01

97

Piping Flexibility  

NASA Technical Reports Server (NTRS)

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.

1978-01-01

98

Heat pipe heat exchanger design considerations  

Microsoft Academic Search

Typical heat pipe heat exchangers (HPHX) are described, along with their advantages, uses, and some problems in HPHX design, and a computer HPHX analysis program is discussed with required input data. The computer program is being developed for analysis of heat exchange performance by finned-tube HPHX and thread-puddle-artery heat pipes. Copper-water heat pipes and carbon steel-Dowtherm A heat pipes are

K. T. Feldman; D. C. Lu

1976-01-01

99

Refrigerant piping  

SciTech Connect

The piping design of an air conditioning system is a critical element in the proper performance of the system. It involves an extremely complex relationship in the flow of refrigerant oil through the various parts of the system. The factor that must be considered in a piping design are the inter-relationships between velocity, pressure, friction and density, as well as the related variables required for proper fluid flow. These variables and relationships can be expressed in long mathematical equations, performance charts, and pressure drop tables for fluid flow through the piping. The improper design and sizing of refrigerant piping in a sealed system may result in loss of system efficiency that could lead to a los of overall system capacity as well as eventual failure of components of the system.

Puzio, H. [Sussex County Vocational Technical School, Sparta, NJ (United States)

1996-10-01

100

Prioritizing Water Pipe Replacement and Rehabilitation by Evaluating Failure Risk  

E-print Network

lines delivering water today encounter serious problems. Corrosion has caused deterioration in pipe lines, which contributes rust to drinking, a serious water quality problem. In addition, pipe line failures have caused social issues, such as suspension...

Lee, Sang Hyun

2012-02-14

101

Heat Pipe Integrated Microsystems  

SciTech Connect

The trend in commercial electronics packaging to deliver ever smaller component packaging has enabled the development of new highly integrated modules meeting the demands of the next generation nano satellites. At under ten kilograms, these nano satellites will require both a greater density electronics and a melding of satellite structure and function. Better techniques must be developed to remove the subsequent heat generated by the active components required to-meet future computing requirements. Integration of commercially available electronics must be achieved without the increased costs normally associated with current generation multi chip modules. In this paper we present a method of component integration that uses silicon heat pipe technology and advanced flexible laminate circuit board technology to achieve thermal control and satellite structure. The' electronics/heat pipe stack then becomes an integral component of the spacecraft structure. Thermal management on satellites has always been a problem. The shrinking size of electronics and voltage requirements and the accompanying reduction in power dissipation has helped the situation somewhat. Nevertheless, the demands for increased onboard processing power have resulted in an ever increasing power density within the satellite body. With the introduction of nano satellites, small satellites under ten kilograms and under 1000 cubic inches, the area available on which to place hot components for proper heat dissipation has dwindled dramatically. The resulting satellite has become nearly a solid mass of electronics with nowhere to dissipate heat to space. The silicon heat pipe is attached to an aluminum frame using a thermally conductive epoxy or solder preform. The frame serves three purposes. First, the aluminum frame provides a heat conduction path from the edge of the heat pipe to radiators on the surface of the satellite. Secondly, it serves as an attachment point for extended structures attached to the satellite such as solar panels, radiators, antenna and.telescopes (for communications or sensors). Finally, the packages make thermal contact to the surface of the silicon heat pipe through soft thermal pads. Electronic components can be placed on both sides of the flexible circuit interconnect. Silicon heat pipes have a number of advantages over heat pipe constructed from other materials. Silicon heat pipes offer the ability to put the heat pipe structure beneath the active components of a processed silicon wafer. This would be one way of efficiently cooling the heat generated by wafer scale integrated systems. Using this technique, all the functions of a satellite could be reduced to a few silicon wafers. The integration of the heat pipe and the electronics would further reduce the size and weight of the satellite.

Gass, K.; Robertson, P.J.; Shul, R.; Tigges, C.

1999-03-30

102

Large-bore pipe decontamination  

SciTech Connect

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.

Ebadian, M.A.

1998-01-01

103

Factory Flow Benchmarking Report  

E-print Network

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 ...

Shields, Thomas J.

104

Benchmarking for Higher Education.  

ERIC Educational Resources Information Center

The chapters in this collection explore the concept of benchmarking as it is being used and developed in higher education (HE). Case studies and reviews show how universities in the United Kingdom are using benchmarking to aid in self-regulation and self-improvement. The chapters are: (1) "Introduction to Benchmarking" (Norman Jackson and Helen

Jackson, Norman, Ed.; Lund, Helen, Ed.

105

Heat Pipes  

NASA Technical Reports Server (NTRS)

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.

1990-01-01

106

Piping Connector  

NASA Technical Reports Server (NTRS)

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

1994-01-01

107

Bag Pipe  

NSDL National Science Digital Library

In this activity, learners explore sound by constructing their very own bagpipe instrument. Learners use PVC pipe, a ziploc bag, rubber tubing, rubber bands, a plastic bottle, and a rubber glove to build their bagpipe. Note: a drill is required, but is not included in the cost of materials.

Workshop, Environmental S.

2011-01-01

108

PRISMATIC CORE COUPLED TRANSIENT BENCHMARK  

SciTech Connect

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.

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

109

Heat Pipe Systems  

NASA Technical Reports Server (NTRS)

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.

1988-01-01

110

Benchmarking short sequence mapping tools  

PubMed Central

Background The development of next-generation sequencing instruments has led to the generation of millions of short sequences in a single run. The process of aligning these reads to a reference genome is time consuming and demands the development of fast and accurate alignment tools. However, the current proposed tools make different compromises between the accuracy and the speed of mapping. Moreover, many important aspects are overlooked while comparing the performance of a newly developed tool to the state of the art. Therefore, there is a need for an objective evaluation method that covers all the aspects. In this work, we introduce a benchmarking suite to extensively analyze sequencing tools with respect to various aspects and provide an objective comparison. Results We applied our benchmarking tests on 9 well known mapping tools, namely, Bowtie, Bowtie2, BWA, SOAP2, MAQ, RMAP, GSNAP, Novoalign, and mrsFAST (mrFAST) using synthetic data and real RNA-Seq data. MAQ and RMAP are based on building hash tables for the reads, whereas the remaining tools are based on indexing the reference genome. The benchmarking tests reveal the strengths and weaknesses of each tool. The results show that no single tool outperforms all others in all metrics. However, Bowtie maintained the best throughput for most of the tests while BWA performed better for longer read lengths. The benchmarking tests are not restricted to the mentioned tools and can be further applied to others. Conclusion The mapping process is still a hard problem that is affected by many factors. In this work, we provided a benchmarking suite that reveals and evaluates the different factors affecting the mapping process. Still, there is no tool that outperforms all of the others in all the tests. Therefore, the end user should clearly specify his needs in order to choose the tool that provides the best results. PMID:23758764

2013-01-01

111

GAPRUS -GENETIC ALGORITHMS BASED PIPE ROUTING USING TESSELLATED OBJECTS  

E-print Network

and sometimes discontinuous problems like pipe routing. Besides, due to limitations in the representation of 3D problems involving 3D freeform obstacles is demonstrated. Key words: Pipe Routing, Genetic AlgorithmsGAPRUS - GENETIC ALGORITHMS BASED PIPE ROUTING USING TESSELLATED OBJECTS Sunand Sandurkar Software

Chen, Wei

112

Three dimensional transport benchmark exercise using THREEDANT  

SciTech Connect

As part of the effort to assess the ability to perform three dimensional transport calculations to solve problems in reactor physics, we describe the THREEDANT code and its application to the set of three-dimensional benchmark problems proposed by Prof. T. Takeda. As part of this benchmarking activity, we display some key indicators as to computational performance and efficiency while displaying the sensitivity of the eigenvalue to Sn order and to spatial mesh size in each of the problems. In order to understand what is being displayed, we summarize the solution strategy incorporated in the code. 1 ref., 3 figs.

Alcouffe, R.E.

1990-01-01

113

Steam bubble collapse, water hammer and piping network response. Volume I. Steam bubble collapse and water hammer in piping systems: experiments and analysis. Final report  

SciTech Connect

Water hammer incidents in conventional and nuclear steam systems are an important problem of broad general interest in piping network design and transient operation. Water hammer in PWR steam generator sparger feed lines has, for example, been a recurrent problem when the sparger becomes uncovered during certain operational transients (Creare 1977). The central goal of this research has been to develop experimental data and supporting analyses that will contribute to the evolving understanding of water hammer created by steam bubble entrapment in a pipe containing subcooled liquid. The first objective of this study has been to obtain a body of experimental data on water hammer initiated by steam bubble collapse. These experiments include measurement of pressure transients and high speed films of the process of bubble collapse and impact, and, in conjunction with Hurwitz (1980), records of the resultant pressure wave propagation through a variety of simple piping configurations and measurements of the induced structural response. The data that have been obtained should be useful in benchmarking existing analytic models and numerical codes.

Gruel, R.; Hurwitz, W.; Huber, P.; Griffith, P.

1980-06-01

114

Epilepsy Research Benchmarks Progress Report  

E-print Network

Epilepsy Research Benchmarks Progress Report 2007 ­ 2012 #12;i Epilepsy Research Benchmarks .................................................................................................................................................................................... 1 Benchmarks Area I - Prevent epilepsy and its progression.......................................................................................................................2 A. Identify as yet unrecognized causes of epilepsy (e.g., genetic, autoimmune and infectious

115

Ad hoc committee on reactor physics benchmarks  

SciTech Connect

In the spring of 1994, an ad hoc committee on reactor physics benchmarks was formed under the leadership of two American Nuclear Society (ANS) organizations. The ANS-19 Standards Subcommittee of the Reactor Physics Division and the Computational Benchmark Problem Committee of the Mathematics and Computation Division had both seen a need for additional benchmarks to help validate computer codes used for light water reactor (LWR) neutronics calculations. Although individual organizations had employed various means to validate the reactor physics methods that they used for fuel management, operations, and safety, additional work in code development and refinement is under way, and to increase accuracy, there is a need for a corresponding increase in validation. Both organizations thought that there was a need to promulgate benchmarks based on measured data to supplement the LWR computational benchmarks that have been published in the past. By having an organized benchmark activity, the participants also gain by being able to discuss their problems and achievements with others traveling the same route.

Diamond, D.J. [Brookhaven National Laboratory, Upton, NY (United States); Mosteller, R.D. [Los Alamos National Laboratory, NM (United States); Gehin, J.C. [Lockheed Martin Energy Systems, Oak Ridge, TN (United States)

1996-12-31

116

Heat pipe technology  

NASA Technical Reports Server (NTRS)

A bibliography of heat pipe technology to provide a summary of research projects conducted on heat pipes is presented. The subjects duscussed are: (1) heat pipe applications, (2) heat pipe theory, (3) design and fabrication, (4) testing and operation, (5) subject and author index, and (6) heat pipe related patents.

1972-01-01

117

MIDACO software performance on interplanetary trajectory benchmarks  

NASA Astrophysics Data System (ADS)

A numerical study of the MIDACO optimization software on the well known GTOP benchmark set, published by the European Space Agency (ESA), is presented. The GTOP database provides trajectory models of real-world interplanetary space missions such as Cassini, Messenger or Rosetta. The trajectory models are formulated as constrained nonlinear optimization problems and are known to be difficult to solve. Here a comprehensive and rigorous numerical analysis of the MIDACO out-of-the-box performance on the GTOP benchmark set is presented and discussed. In the past, the putative best known solutions of these benchmarks often required several months and even years to be found. In this contribution it will be shown, that MIDACO is able to solve five out of seven of these benchmarks to their best known solution within minutes to hours.

Schlueter, Martin

2014-08-01

118

Benchmark calculations from summarized data: an example  

SciTech Connect

Benchmark calculations often are made from data extracted from publications. Such datamay not be in a formmost appropriate for benchmark analysis, and, as a result, suboptimal and/or non-standard benchmark analyses are often applied. This problem can be mitigated in some cases using Monte Carlo computational methods that allow the likelihood of the published data to be calculated while still using an appropriate benchmark dose (BMD) definition. Such an approach is illustrated herein using data from a study of workers exposed to styrene, in which a hybrid BMD calculation is implemented from dose response data reported only as means and standard deviations of ratios of scores on neuropsychological tests from exposed subjects to corresponding scores from matched controls. The likelihood of the data is computed using a combination of analytic and Monte Carlo integration methods.

Crump, K. S.; Teeguarden, Justin G.

2009-03-01

119

WIPP Benchmark calculations with the large strain SPECTROM codes  

SciTech Connect

This report provides calculational results from the updated Lagrangian structural finite-element programs SPECTROM-32 and SPECTROM-333 for the purpose of qualifying these codes to perform analyses of structural situations in the Waste Isolation Pilot Plant (WIPP). Results are presented for the Second WIPP Benchmark (Benchmark II) Problems and for a simplified heated room problem used in a parallel design calculation study. The Benchmark II problems consist of an isothermal room problem and a heated room problem. The stratigraphy involves 27 distinct geologic layers including ten clay seams of which four are modeled as frictionless sliding interfaces. The analyses of the Benchmark II problems consider a 10-year simulation period. The evaluation of nine structural codes used in the Benchmark II problems shows that inclusion of finite-strain effects is not as significant as observed for the simplified heated room problem, and a variety of finite-strain and small-strain formulations produced similar results. The simplified heated room problem provides stratigraphic complexity equivalent to the Benchmark II problems but neglects sliding along the clay seams. The simplified heated problem does, however, provide a calculational check case where the small strain-formulation produced room closures about 20 percent greater than those obtained using finite-strain formulations. A discussion is given of each of the solved problems, and the computational results are compared with available published results. In general, the results of the two SPECTROM large strain codes compare favorably with results from other codes used to solve the problems.

Callahan, G.D.; DeVries, K.L. [RE/SPEC, Inc., Rapid City, SD (United States)

1995-08-01

120

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

E-print Network

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

Rocha, Ramses Rodriguez

2012-06-07

121

Benchmarking expert system tools  

NASA Technical Reports Server (NTRS)

As part of its evaluation of new technologies, the Artificial Intelligence Section of the Mission Planning and Analysis Div. at NASA-Johnson has made timing tests of several expert system building tools. Among the production systems tested were Automated Reasoning Tool, several versions of OPS5, and CLIPS (C Language Integrated Production System), an expert system builder developed by the AI section. Also included in the test were a Zetalisp version of the benchmark along with four versions of the benchmark written in Knowledge Engineering Environment, an object oriented, frame based expert system tool. The benchmarks used for testing are studied.

Riley, Gary

1988-01-01

122

Heat Pipe Precools and Reheats Dehumidified Air  

NASA Technical Reports Server (NTRS)

Precooling and reheating by heat pipe reduces operating costs of air-conditioning. Warm air returned from air-conditioned space and cooled air supplied are precooled and reheated, respectively, by each other through a heat pipe. Heat-pipe technology brought to bear on problem of conserving airconditioning energy in hot, humid environments. Any increase in the cost of equipment due to installation of heat-pipe heat exchangers expected to be recovered in energy savings during service period of 2 years or less.

Koning, R. C.; Boggs, W. H.; Barnett, U. R.; Dinh, K.

1986-01-01

123

Flow conditions of fresh mortar and concrete in different pipes  

SciTech Connect

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.

Jacobsen, Stefan, E-mail: stefan.jacobsen@ntnu.n [Norwegian University of Science and Technology, Dept of Structural Engineering, Trondheim (Norway); Haugan, Lars; Hammer, Tor Arne [SINTEF Byggforsk AS Building and Infrastructure, Trondheim (Norway); Kalogiannidis, Evangelos [Norwegian University of Science and Technology, Dept of Structural Engineering, Trondheim (Norway)

2009-11-15

124

Benchmark Solutions for Computational Aeroacoustics (CAA) Code Validation  

NASA Technical Reports Server (NTRS)

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.

Scott, James R.

2004-01-01

125

Higher Education Ranking and Leagues Tables: Lessons Learned from Benchmarking  

ERIC Educational Resources Information Center

The paper intends to contribute to the debate on ranking and league tables by adopting a critical approach to ranking methodologies from the point of view of a university benchmarking exercise. The absence of a strict benchmarking exercise in the ranking process has been, in the opinion of the author, one of the major problems encountered in the

Proulx, Roland

2007-01-01

126

Applications of heat pipes to cool PWBS and hybrid microcircuits  

NASA Technical Reports Server (NTRS)

Some of the advanced thermal management techniques used to reduce operating junction temperature under extreme environmental temperature conditions are discussed. Heat pipes in actual electronic packaging applications, and those under development, are discussed. Performance characteristics of heat pipes are given, and examples are described of how thermal problems in electronic packaging are solved through the use of heat pipes.

Sekhon, K. S.

1986-01-01

127

Shielding Benchmark Computational Analysis  

SciTech Connect

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).

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

2000-09-17

128

Storage-Intensive Supercomputing Benchmark Study  

SciTech Connect

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.

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

2007-10-30

129

Randomized benchmarking with confidence  

NASA Astrophysics Data System (ADS)

Randomized benchmarking is a promising tool for characterizing the noise in experimental implementations of quantum systems. In this paper, we prove that the estimates produced by randomized benchmarking (both standard and interleaved) for arbitrary Markovian noise sources are remarkably precise by showing that the variance due to sampling random gate sequences is small. We discuss how to choose experimental parameters, in particular the number and lengths of random sequences, in order to characterize average gate errors with rigorous confidence bounds. We also show that randomized benchmarking can be used to reliably characterize time-dependent Markovian noise (e.g., when noise is due to a magnetic field with fluctuating strength). Moreover, we identify a necessary property for time-dependent noise that is violated by some sources of non-Markovian noise, which provides a test for non-Markovianity.

Wallman, Joel J.; Flammia, Steven T.

2014-10-01

130

Performance improvement through benchmarking  

SciTech Connect

Benchmarking has become very popular in the past few years, taking its place in the list of management tools alongside organizational restructuring, total quality management, process reengineering, and others as ways to make improvements to operational and financial performance. Yet much is misunderstood about the technique, and there is substantial room for improvement in its application across industry, and particularly within the utility industry. The purpose of this paper is to explain some of the details of benchmarking, including its capabilities and limitations, and demonstrate how different applications require different approaches to benchmarking. The intent is to provide a brief overview of the different potential uses, and then, through a case example, show how the different capabilities can be put to use.

Buckstaff, K. [Theodore Barry & Associates, Los Angeles, CA (United States)

1994-12-31

131

Insulated pipe clamp design  

SciTech Connect

Thin wall large diameter piping for breeder reactor plants can be subjected to significant thermal shocks during reactor scrams and other upset events. On the Fast Flux Test Facility, the addition of thick clamps directly on the piping was undesired because the differential metal temperatures between the pipe wall and the clamp could have significantly reduced the pipe thermal fatigue life cycle capabilities. Accordingly, an insulated pipe clamp design concept was developed. The design considerations and methods along with the development tests are presented. Special considerations to guard against adverse cracking of the insulation material, to maintain the clamp-pipe stiffness desired during a seismic event, to minimize clamp restraint on the pipe during normal pipe heatup, and to resist clamp rotation or spinning on the pipe are emphasized.

Anderson, M.J.; Hyde, L.L.; Wagner, S.E.; Severud, L.K.

1980-01-01

132

2012 eddy current benchmark modeling of impedance variation in coil due to a thin longitudinal through-wall notch in an inconel 600 tube  

NASA Astrophysics Data System (ADS)

The 2012 Eddy Current Benchmark Problem involves the inspection of an inconel pipe using an internal pancake coil situated with its axis perpendicular to the axis of the pipe. The experimental data were supported by the Benchmark Eddy Current 2012, as released by the World Federation of Non Destructive Evaluation Centers (WFNDEC). The software OPERA 3D and COMSOL were used by the authors to solve the proposed simulation problem. The simulated results were in good agreement with the experimental ones. However some simulated results exhibited a small variation in the impedance and electrical resistance between the base material and the region around the notch. The values of these changes were plotted as a function of the displacement of the sensor over the notch region. The calculations were made for frequencies of 25kHz to 200kHz. A good agreement was obtained at low frequency. However, the simulation at high frequencies presented differences, which can be attributed to the mesh refinement. The finite elements in both software should be adjusted to two regions: the change of the small notch region and its neighborhood. It is important to adjust the mesh size parameter to compensate the low skin depth inherent to eddy current testing at high frequencies.

Rebello, Joo Marcos; Camerini, Cesar; Rocha, Joo Vicente; Areiza, Maria Cristina

2013-01-01

133

Benchmarking the World's Best  

ERIC Educational Resources Information Center

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

Tucker, Marc S.

2012-01-01

134

Accelerated Randomized Benchmarking  

E-print Network

Quantum information processing offers promising advances for a wide range of fields and applications, provided that we can efficiently assess the performance of the control applied in candidate systems. That is, we must be able to determine whether we have implemented a desired gate, and refine accordingly. Randomized benchmarking reduces the difficulty of this task by exploiting symmetries in quantum operations. Here, we bound the resources required for benchmarking and show that, with prior information, we can achieve several orders of magnitude better accuracy than in traditional approaches to benchmarking. Moreover, by building on state-of-the-art classical algorithms, we reach these accuracies with near-optimal resources. Our approach requires an order of magnitude less data to achieve the same accuracies and to provide online estimates of the errors in the reported fidelities. We also show that our approach is useful for physical devices by comparing to simulations. Our results thus enable the application of randomized benchmarking in new regimes, and dramatically reduce the experimental effort required to assess control fidelities in quantum systems. Finally, our work is based on open-source scientific libraries, and can readily be applied in systems of interest.

Christopher Granade; Christopher Ferrie; D. G. Cory

2014-04-21

135

Educational Benchmarks, 1996.  

ERIC Educational Resources Information Center

Southern Regional Education Board (SREB) monitors the South's education reforms through "Benchmarks" reports, tracking progress toward 12 goals for elementary, secondary, and higher education that were endorsed by the SREB in 1988. The board collects state-by-state data every 2 years and compares how states are doing on over 60 different

Creech, Joseph D.

136

On Benchmarking Optical Flow  

Microsoft Academic Search

Evaluating the performance of optical flow algorithms has been difficult because of the lack of ground truth data sets for complex scenes. We present a new method for generating motion fields from real sequences containing polyhedral objects and present a test suite for benchmarking optical flow algorithms consisting of complex synthetic sequences and real scenes with ground truth. We provide

Brendan Mccane; Kevin Novins; D. Crannitch; Ben Galvin

2001-01-01

137

Benchmarks: WICHE Region 2012  

ERIC Educational Resources Information Center

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

Western Interstate Commission for Higher Education, 2013

2013-01-01

138

Benchmarking firm performance  

Microsoft Academic Search

Purpose The aim of the paper is to provide a framework for benchmarking firm performance (profitability) using panel data. Further, to illustrate how the estimation results can be used for simulation (what if?) exercises. Design\\/methodology\\/approach The authors apply the econometric techniques used in panel data to estimate profit functions, thereby enabling us to compute measures of firm efficiencies

Peter Dawkins; Simon Feeny; Mark N. Harris

2007-01-01

139

Airport Capacity Benchmark Report 2001  

NSDL National Science Digital Library

Released in April 2001 by the FAA (Federal Aviation Administration), this report provides the first capacity benchmarks for 31 of the nation's busiest airports. Capacity benchmarks are defined as "the maximum number of flights an airport can routinely handle in an hour." The report finds, among other things, that at a number of airports so many flights are scheduled that it is simply not possible for all of them to take off and land on time. The worst offender in 2000 was New York LaGuardia, with 15.6 percent of takeoffs or landings delayed, more than twice as many as the second-ranked airport, Chicago O'Hare. Predictably, opinion is divided on the root of the problem, with the airlines blaming an antiquated air traffic control system and too few runways and critics blaming the airlines for over-scheduling at peak travel times. The full text of the 195-page report may be downloaded in .pdf or Word format at the FAA site.

2001-01-01

140

Benchmarking image fusion system design parameters  

NASA Astrophysics Data System (ADS)

A clear and absolute method for discriminating between image fusion algorithm performances is presented. This method can effectively be used to assist in the design and modeling of image fusion systems. Specifically, it is postulated that quantifying human task performance using image fusion should be benchmarked to whether the fusion algorithm, at a minimum, retained the performance benefit achievable by each independent spectral band being fused. The established benchmark would then clearly represent the threshold that a fusion system should surpass to be considered beneficial to a particular task. A genetic algorithm is employed to characterize the fused system parameters using a Matlab implementation of NVThermIP as the objective function. By setting the problem up as a mixed-integer constraint optimization problem, one can effectively look backwards through the image acquisition process: optimizing fused system parameters by minimizing the difference between modeled task difficulty measure and the benchmark task difficulty measure. The results of an identification perception experiment are presented, where human observers were asked to identify a standard set of military targets, and used to demonstrate the effectiveness of the benchmarking process.

Howell, Christopher L.

2013-06-01

141

Pipe-to-pipe impact program  

SciTech Connect

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.

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

1984-06-01

142

Heat pipes. [technology utilization  

NASA Technical Reports Server (NTRS)

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.

1975-01-01

143

Antigravity heat pipe  

Microsoft Academic Search

The general design and principle of operation of an antigravity heat pipe, in which the heat transfer agent is supplied to the evaporator against the force of gravity, are descussed. Analytical expressions describing the operation of the heat pipe are presented, as are experimental results obtained for an acetone-charged antigravity heat pipe.

N. I. Kliuev

1989-01-01

144

Previewing Semantic Web Pipes  

Microsoft Academic Search

In this demo we present a first implementation of Semantic Web Pipes, a powerful tool to build RDF-based mashups. Semantic Web pipes are defined in XML and when executed they fetch RDF graphs on the Web, operate on them, and produce an RDF output which is itself accessible via a stable URL. Humans can also use pipes directly thanks to

Christian Morbidoni; Danh Le Phuoc; Axel Polleres; Matthias Samwald; Giovanni Tummarello

2008-01-01

145

Leaks in pipe networks  

USGS Publications Warehouse

Leak detection in water-distribution systems can be accomplished by solving an inverse problem using measurements of pressure and/or flow. The problem is formulated with equivalent orifice areas of possible leaks as the unknowns. Minimization of the difference between measured and calculated heads produces a solution for the areas. The quality of the result depends on number and location of the measurements. A sensitivity matrix is key to deciding where to make measurements. Both location and magnitude of leaks are sensitive to the quantity and quality of pressure measurements and to how well the pipe friction parameters are known. The overdetermined problem (more measurements than suspected leaks) gives the best results, but some information can be derived from the underdetermined problem. The variance of leak areas, based on the quality of system characteristics and pressure data, indicates the likely accuracy of the results. The method will not substitute for more traditional leak surveys but can serve as a guide and supplement.

Pudar, Ranko S.; Liggett, James A.

1992-01-01

146

Randomized Benchmarking with Confidence  

E-print Network

Randomized benchmarking is a promising tool for characterizing the noise in experimental implementations of quantum systems. In this paper, we prove that the estimates produced by randomized benchmarking (both standard and interleaved) for arbitrary Markovian noise sources are remarkably precise by showing that the variance of the underlying distribution is small. In particular, we prove that the variance for arbitrary $d$-level systems decreases exponentially in the sequence length to a small constant (that is zero for unital noise), and moreover, the variance is bounded by the error rate for short sequences. In the special case of a single qubit, we prove that the variance scales with the square of the product of the sequence length and the error rate for the regimes currently being investigated experimentally. We also show that randomized benchmarking can be used to reliably characterize the time-dependent average gate fidelity and diamond distance for Markovian noise (which characterize the average and worst-case error rates, respectively), provided the noise is sufficiently close to gate-independent at each time step, and we provide a quantitative condition for stability with respect to these perturbations. Moreover, we identify a necessary property for time-dependent noise that is violated by some sources of non-Markovian noise, which provides a test for non-Markovianity. Finally, we identify a necessary choice of parameters for randomized benchmarking experiments, namely, that the number of random sequences sampled should scale with the length of the sequence in order for all data points to have comparable uncertainties.

Joel J. Wallman; Steven T. Flammia

2014-04-24

147

Estimating with Benchmark Fractions  

NSDL National Science Digital Library

Teachers can use this interactive tool to help students develop fraction sense. After a teacher places a fraction, decimal, or expression on the screen, students determine which given benchmark number it is closest to. An adjustable number line supports conceptual understanding. This page includes a video demonstration of the tool and sample lessons from the Conceptua curriculum. Free registration is required to use the tool. A paid subscription is necessary to access full curriculum and allow full student use.

2011-01-01

148

Pipe Line Control  

NASA Technical Reports Server (NTRS)

The array of tanks, pipes and valves in the photo below is a petroleum tank farm in Georgia, part of a petrochemical pipe line system that moves refined petroleum products from Texas and Louisiana to the mid-Eastern seaboard. The same pipes handle a number of different products, such as gasoline, kerosene, jet fuel or fuel oil. The fluids are temporarily stored in tanks, pumped into the pipes in turn and routed to other way stations along the pipe line. The complex job of controlling, measuring and monitoring fuel flow is accomplished automatically by a computerized control and communications system which incorporates multiple space technologies.

1978-01-01

149

Welding bimetal pipes in duplex stainless steel  

Microsoft Academic Search

Butting bimetal pipes in duplex stainless steel are quite recent and present a set of interesting characteristics especially\\u000a for oil and gas transportation, namely weight to corrosion resistance ratio. Gas tungsten arc (GTA) welding is used to join\\u000a these pipes, but several problems are identified as lack of penetration and cracking resulting not only from the material\\u000a itself, but also

A. M. Torbati; R. M. Miranda; L. Quintino; S. Williams

2011-01-01

150

Strength and reliability of piping systems  

Microsoft Academic Search

Analytical and numerical methods have been developed for the solution of stress-strain and limit state problems of piping\\u000a systems (in the case of the presence of flaws in them as well). The fracture strength of pipe steels during long-term service\\u000a has been studied. A methodology and a software have been developed for the assessment of stress-strain state to extend the

A. Ya. Krasovskii; I. V. Orynyak

2010-01-01

151

Acoustical wave propagation in buried water filled pipes  

E-print Network

This thesis presents a comprehensive way of dealing with the problem of acoustical wave propagation in cylindrically layered media with a specific application in water-filled underground pipes. The problem is studied in ...

Kondis, Antonios, 1980-

2005-01-01

152

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...

153

Using Flexible Pipe (poly-pipe) with Surface Irrigation  

E-print Network

out (Fig. 2). roll of poly-pipe is needed, connect the rolls with a corrugated pipe (Figs. 5a, 5b and 5c). Be sure to roll each end back on itself (as previously described) be- fore strapping it to the supply pipe (Fig. 4a). Figure 2. Poly-pipe set... rubber straps to connect the poly-pipe to the supplying pipe. Figure 5a. Connecting two rolls of poly-pipe. Figure 5b. Using a corrugated PVC pipe to connect two rolls of poly-pipe. Figure 5c. Making a tight con- nection to avoid water leaks. Figure 3...

Peries, Xavier; Enciso, Juan

2005-10-05

154

Monte Carlo Benchmark Calculations for 400MWth PBMR Core  

Microsoft Academic Search

Benchmark calculations for the core of the 400MWth Pebble-bed Modular Reactor (PBMR), being developed in South Africa, were carried out by using MCNP5 code as a part of establishing Monte Carlo computation system for HTGR core analysis. After the detailed MCNP modeling of the whole facility, two neutronic benchmark problems, for fresh fuel and cold conditions(Case F-1), and first core

Hong-Chul KIM; Soon Young KIM; Jong Kyung KIM; Jae Man NOH

155

65. FIRE SUPPRESSION PIPES BEHIND FLAME BUCKET. PIPES TO UMBILICAL ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

65. FIRE SUPPRESSION PIPES BEHIND FLAME BUCKET. PIPES TO UMBILICAL MAST IN LOWER LEFT CORNER; PIPES TO LAUNCHER IN UPPER LEFT CORNER; PIPES TO FLAME BUCKET IN LOWER RIGHT CORNER OF PHOTOGRAPH. POTABLE WATER PIPING IN UPPER RIGHT CORNER OF PHOTO. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

156

Benchmarking Corporate Energy Management  

E-print Network

presented. That information can serve as the foundation of a benchmarking tool. To do just that, the information has been organized in an Excel Workbook that can be used by a company to self score itself. for example, the first element is top management... management is the policy statement Issued'? Answers include the CEO (worth 50 points) the CFO or COO (worth 35 points), a VP (20 points), and other (5 points). Other sections will include self-scoring on: ? Energy reduction goals ? Communication...

Norland, D. L.

157

Benchmarking, BOMA BESt and BBEER  

E-print Network

?or?worse?than?????? Energy?Use?Intensity?(EUI)?=?? total?energy?consumed?in?one?year?(ekWh)?/?total?floor?space?of? the?building?(ft2) Benchmarking and BBEER 2013 ? reliable?information on?energy?use?and?benefits?of?improvements; ? prioritize poorly...?energy?efficiency?among?building?occupants. BENCHMARKING ? Benefits Source:?NRCan Benchmarking and BBEER 2013 ABOUT BOMA BESt ? Program Description Building?Environmental?Standards?(BESt) ? Environmental?performance?and?management? practices?of?existing?buildings ? Five...

Smiciklas, J.

2013-01-01

158

The design of a scalable, fixed-time computer benchmark  

SciTech Connect

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.

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

1990-10-01

159

Piping inspection instrument carriage  

SciTech Connect

This invention is comprised of a pipe inspection instrument carriage for use with a pipe crawler or other locomotion means for performing internal inspections of piping surfaces. The carriage has a front leg assembly, a rear leg assembly and a central support connecting the two assemblies and for mounting an instrument arm having inspection instruments. The instrument arm has means mounted distally thereon for axially aligning the inspection instrumentation and means for extending the inspection instruments radially outward to operably position the inspection instruments on the piping interior. Also, the carriage has means for rotating the central support and the front leg assembly with respect to the rear leg assembly so that the inspection instruments azimuthally scan the piping interior. The instrument carriage allows performance of all piping inspection operations with a minimum of moving parts, thus decreasing the likelihood of performance failure.

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

1993-09-20

160

Deployable Heat Pipe Radiator  

NASA Technical Reports Server (NTRS)

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.

Edelstein, F.

1975-01-01

161

Using Games for Benchmarking and Representing the Complete Solution Space using Symbolic Techniques  

Microsoft Academic Search

Games often are inherently multi-valued problems and their wide variety offers different graduations of complex - ity. Moreover a lot of games have a parameter, like board- size that allows to generate differently sized instances ofthe same problem. All this makes them perfectly suitable for benchmarking in the multi-valued domain. So far the lack of benchmarks in this area often

Grschwin Fey; Sebastian Kinder; Rolf Drechsler

2003-01-01

162

Furan flare piping rupture analysis  

SciTech Connect

The FRP flare piping is part of a typical flare system that is used to burn gases from the relief valves in the area, vent gases when the incinerator is down and vents from selected towers. All exhaust gases enter a large flare seal pot where a water seal is maintained. These gases are ignited by a continuous natural gas pilot with propane used as a back-up. A 12 inch (305 mm) diameter FRP piping section containing Furan resin disintegrated after four years of service in a vapor relief system. External inspection of the flare stack conducted just three months earlier revealed no obvious problems. Also, during the ensuring period, there were no upsets in temperature, pressure or process operations. A detailed investigation determined that excessive mechanical stresses at the unsupported 45 degree elbow joints led to strain corrosion and subsequent crumbling of the FRP material. The remainder of the piping and flanges were in good condition. Steps necessary to minimize future problems and the need for industry wide design, inspection and maintenance guidelines are discussed.

Dias, O.C. [Lyondell-Citgo Refining, Houston, TX (United States)

1997-08-01

163

Hydrogen Piping Experience in Chevron  

E-print Network

piping specifications and practices for hydrogen service (Cont'd) Seamless pipe (SA 106GrB or lessHydrogen Piping Experience in Chevron Refining Ned Niccolls Materials Engineer Chevron Energy perspectives from long term use of hydrogen piping in refining. Piping specifications and practices. The (few

164

Abrasion resistant heat pipe  

DOEpatents

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.

Ernst, Donald M. (Leola, PA)

1984-10-23

165

A pipe stress program for the microcomputer  

SciTech Connect

Explains how a FOCAL program can be used to solve difficult multianchor pipe stress problems. Presents a 6-anchor problem that will run in a half-hour on a small micro. Gives a general discussion of the problem with a little history behind some of the formulas. Other parts of the series will offer the FOCAL program; a typical 6-anchor example showing how to enter data and how to run the program; and a very simple single plane, 3-anchor example. The calculation method involves dividing a piping system into branches and trunk pieces. Each branch is broken up into members consisting of a piece of straight pipe and half of the elbow which is simulated by a short tangent, as shown in a diagram. A flexibility matrix is calculated for every member, and these 6 X 7 matrices are all knitted together to produce one 6 X 7 matrix. Tables give knitting logic and unraveling logic.

Bridge, T.E.

1983-02-01

166

Heat Pipe Materials Compatibility  

NASA Technical Reports Server (NTRS)

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.

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

1976-01-01

167

TsunaFLASH Benchmark and Its Verifications  

NASA Astrophysics Data System (ADS)

In the end of year 2008 TsunAWI (Tsunami unstructured mesh finite element model developed at Alfred Wegener Institute) by Behrens et al. (2006 - 2008) [Behrens, 2008], had been launched as an operational model in the German - Indonesian Tsunami EarlyWarning System (GITEWS) framework. This model has been benchmarked and verified with 2004 Sumatra-Andaman mega tsunami event [Harig et al., 2008]. A new development uses adaptive mesh refinement to improve computational efficiency and accuracy, this approach is called TsunaFLASH [Pranowo et al., 2008]. After the initial development and verification phase with stabilization efforts, and study of refinement criteria, the code is now mature enough to be validated with data. This presentation will demonstrate results of TsunaFLASH for the experiments with diverse mesh refinement criteria, and benchmarks; in particular the problem set-1 of IWLRM, and field data of the Sumatra-Andaman 2004 event.

Pranowo, Widodo; Behrens, Joern

2010-05-01

168

Internal Benchmarking for Institutional Effectiveness  

ERIC Educational Resources Information Center

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

Ronco, Sharron L.

2012-01-01

169

Benchmarking Higher Education ICT Infrastructure  

Microsoft Academic Search

The paper benchmarks ICT infrastructure in the context of academic computing implementation at Malaysian higher education institutions. Three research questions are central to this study. What are the indicators for benchmarking ICT infrastructure? What is the general performance of higher education institutions in Malaysia? In order to answer these questions, a nationwide survey was conducted involving 90 higher education institutions

Shamsul Anuar Mokhtar; Rose Alinda Alias; Azizah Abdul Rahman

170

NAS Grid Benchmarks: A Tool for Grid Space Exploration  

NASA Technical Reports Server (NTRS)

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.

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

2001-01-01

171

Regional Competitive Intelligence: Benchmarking and Policymaking  

Microsoft Academic Search

Huggins R. Regional competitive intelligence: benchmarking and policy-making, Regional Studies. Benchmarking exercises have become increasingly popular within the sphere of regional policy-making. This paper analyses the concept of regional benchmarking and its links with regional policy-making processes. It develops a typology of regional benchmarking exercises and benchmarkers, and critically reviews the literature. It is argued that critics of regional benchmarking

Robert Huggins

2010-01-01

172

OBSERVATION OF NONLINEAR TRAVELLING WAVES IN TURBULENT PIPE FLOW  

Microsoft Academic Search

Transition to turbulence in pipe flow has posed a riddle in fluid dynamics since the pioneering experiments of Reynolds[1]. Although the laminar flow is linearly stable for all flow rates, practical pipe flows become turbulent at large enough flow speeds. Turbulence arises suddenly and fully without distinct steps and without a clear critical point. The complexity of this problem has

Bjrn Hof; Casimir Doorne; Jerry Westerweel; Frans Nieuwstadt

173

Aircraft Engine Gas Path Diagnostic Methods: Public Benchmarking Results  

NASA Technical Reports Server (NTRS)

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.

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

2013-01-01

174

Extendable pipe crawler  

DOEpatents

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.

Hapstack, M.

1991-05-28

175

Common causes of material degradation in buried piping  

SciTech Connect

Buried pipe may fail for innumerable reasons. Causes can be mechanical damage/breakage, chemically initiated corrosion, or a combination. Failures may originate either internally or externally on the pipe. They may be related to flaws in the design, to excessive or unanticipated internal pressure or ground level loading, and/or to poor or uncertain installation practice. Or the pipe may simply ``wear out`` in service. Steel is strong and very forgiving in underground applications, especially with regard to backfill. However, soil support developed through densification or compaction is critical for brittle concrete and vitrified clay tile pipe, and is very important for cast iron and plastic pipe. Chemistry of the soil determines whether or not it will enhance corrosion or other types of degradation. Various causes and mechanisms for deterioration of buried pipe are indicated. Some peculiarities of the different materials of construction are characterized. Repair methods and means to circumvent special problems are described.

Jenkins, C.F.

1997-01-20

176

Benchmarking in Academic Pharmacy Departments  

PubMed Central

Benchmarking in academic pharmacy, and recommendations for the potential uses of benchmarking in academic pharmacy departments are discussed in this paper. Benchmarking is the process by which practices, procedures, and performance metrics are compared to an established standard or best practice. Many businesses and industries use benchmarking to compare processes and outcomes, and ultimately plan for improvement. Institutions of higher learning have embraced benchmarking practices to facilitate measuring the quality of their educational and research programs. Benchmarking is used internally as well to justify the allocation of institutional resources or to mediate among competing demands for additional program staff or space. Surveying all chairs of academic pharmacy departments to explore benchmarking issues such as department size and composition, as well as faculty teaching, scholarly, and service productivity, could provide valuable information. To date, attempts to gather this data have had limited success. We believe this information is potentially important, urge that efforts to gather it should be continued, and offer suggestions to achieve full participation. PMID:21179251

Chisholm-Burns, Marie; Nappi, Jean; Gubbins, Paul O.; Ross, Leigh Ann

2010-01-01

177

Benchmarking parallel image analysis systems  

NASA Astrophysics Data System (ADS)

Parallel image analysis systems are shown by the Abingdon Cross benchmark to excel over all other architectures both in terms of speed and cost performance. The Abingdon Cross benchmark is task specific so that the performance of the system under test can be optimized and adjusted to take full advantage of the system's capabilities. The authors have devised a new set of benchmarks for parallel image analysis systems consisting of individual tests of the following operations: (1) Point process, (2) integer convolution, (3) Fourier transform, (4) Boolean algebra, (5) histograming, (6) maximum ranking, (7) median ranking, (8) erosion! dilation, (9) memory to disk transfer, and (10) memory to display transfer.

Preston, Kendall, Jr.; Seigart, Carol

1990-07-01

178

California commercial building energy benchmarking  

SciTech Connect

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.

Kinney, Satkartar; Piette, Mary Ann

2003-07-01

179

Gas pipe explorer robot  

NASA Technical Reports Server (NTRS)

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.

Wilcox, Brian (Inventor)

2004-01-01

180

Decay of Turbulence in Pipe Flow  

Microsoft Academic Search

A novel experiment has been devised which provides direct evidence for critical point behavior in the longstanding problem of the transition to turbulence in a pipe. The novelty lies in the quenching of turbulence by reducing the Reynolds number and observing the decay of disordered motion. Divergence of the time scales implies underlying deterministic dynamics which are analogous to those

J. Peixinho; T. Mullin

2006-01-01

181

Large variable conductance heat pipe. Transverse header  

NASA Technical Reports Server (NTRS)

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.

Edelstein, F.

1975-01-01

182

Flexible ultrasonic pipe inspection apparatus  

DOEpatents

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.

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

1994-01-01

183

Experimenting with a "Pipe" Whistle  

ERIC Educational Resources Information Center

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

Stafford, Olga

2012-01-01

184

Improved Thin, Flexible Heat Pipes  

NASA Technical Reports Server (NTRS)

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.

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

2004-01-01

185

Benchmarking hypercube hardware and software  

NASA Technical Reports Server (NTRS)

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.

Grunwald, Dirk C.; Reed, Daniel A.

1986-01-01

186

Benchmarking for the Learning and Skills Sector.  

ERIC Educational Resources Information Center

This document is designed to introduce practitioners in the United Kingdom's learning and skills sector to the principles and practice of benchmarking. The first section defines benchmarking and differentiates metric, diagnostic, and process benchmarking. The remainder of the booklet details the following steps of the benchmarking process: (1) get

Owen, Jane

187

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

SciTech Connect

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.

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

2001-09-29

188

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

NASA Technical Reports Server (NTRS)

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.

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

2002-01-01

189

Robot design for leak detection in water-pipe systems  

E-print Network

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 ...

Choi, Changrak

2012-01-01

190

Heat pipe manufacturing study  

NASA Technical Reports Server (NTRS)

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.

Edelstein, F.

1974-01-01

191

Miniature pipe crawler tractor  

DOEpatents

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.

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

192

Heat pipe development  

NASA Technical Reports Server (NTRS)

The objective of this program was to investigate analytically and experimentally the performance of heat pipes with composite wicks--specifically, those having pedestal arteries and screwthread circumferential grooves. An analytical model was developed to describe the effects of screwthreads and screen secondary wicks on the transport capability of the artery. The model describes the hydrodynamics of the circumferential flow in triangular grooves with azimuthally varying capillary menisci and liquid cross-sections. Normalized results were obtained which give the influence of evaporator heat flux on the axial heat transport capability of the arterial wick. In order to evaluate the priming behavior of composite wicks under actual load conditions, an 'inverted' glass heat pipe was designed and constructed. The results obtained from the analysis and from the tests with the glass heat pipe were applied to the OAO-C Level 5 heat pipe, and an improved correlation between predicted and measured evaporator and transport performance were obtained.

Bienart, W. B.

1973-01-01

193

Flexible drill pipe  

SciTech Connect

A flexible pipe is described which consists of: an elongated tubular member subdivided into a plurality of segments of rigid pipe of substantial wall thickness in end-to-end relationship with a plurality of interlocking teeth and complementary recesses on each end of the segments intermediate the ends of the tubular member, the teeth of one segment being positioned in the recesses of, and interlocking the teeth of, the adjacent segment with sufficient clearance to form a joint permitting limited relative movement between the segments, each of the teeth comprising an arcuate crown portion with its arc extending generally axially of the pipe, a tapered base portion and a substantially flat shoulder area extending between the crown and base portions in a direction generally circumferentially of the pipe.

Hatten, J.L.

1986-07-15

194

Benchmarks for GADRAS performance validation.  

SciTech Connect

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.

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

2009-09-01

195

Fault-tolerant model predictive control of a wind turbine benchmark  

E-print Network

Fault-tolerant model predictive control of a wind turbine benchmark X. Yang J.M. Maciejowski tolerant control problem of a wind turbine benchmark. A hierarchical controller with model predictive pre component of the wind turbine. The global MPC is used to schedule the operation of the components

Cambridge, University of

196

On a Successful Application of Multi-Agent Reinforcement Learning to Operations Research Benchmarks  

E-print Network

On a Successful Application of Multi-Agent Reinforcement Learning to Operations Research Benchmarks reinforcement learning techniques for a new category of challenging benchmark problems from the field of Operations Research. We demonstrate that interpreting and solving the task of job-shop scheduling as a multi

Teschner, Matthias

197

NAFEMS Finite Element Benchmarks for MDG Code Verification  

SciTech Connect

NAFEMS was originally founded at the United Kingdom's National Engineering Laboratory as the National Agency for Finite Element Methods and Standards. It was subsequently privatized as the not-for-profit organization NAFEMS, Ltd., but retains its mission ''To promote the safe and reliable use of finite element and related technology''. That mission has been pursued in part by sponsoring a series of studies that published benchmarked deemed suitable to assess the basic accuracy of engineering simulation tools. The early studies focused on FEA for linear solid and structural mechanics and then extended to nonlinear solid mechanics, eventually including contact. These benchmarks are complemented by educational materials concerning analysis technologies and approaches. More recently NAFEMS is expanding to consider thermal-fluid problems. Further information is available at www.nafems.org. Essentially all major commercial firms selling FEA for solid mechanics are members of NAFEMS and it seemed clear that Methods Development Group should leverage from this information resource, too. In 2002, W Program ASCI funding purchased a three-year membership in NAFEMS. In the summer of 2003 the first author hosted a summer graduate student to begin modeling some of the benchmark problems. We concentrated on NIKE3D, as the benchmarks are most typically problems most naturally run with implicit FEA. Also, this was viewed as a natural path to generate verification problems that could be subsequently incorporated into the Diablo code's test suite. This report documents and archives our initial efforts. The intent is that this will be a ''living document'' that can be expanded as further benchmarks are generated, run, interpreted and documented. To this end each benchmark, or related grouping, is localized in its own section with its own pagination. Authorship (test engineers) will be listed section by section.

Greer, R; Ferencz, R M

2004-02-24

198

Special-relativistic Smoothed Particle Hydrodynamics: a benchmark suite  

E-print Network

formulation differs from earlier approaches in its artificial viscosity and in the use of special- relativistic "grad-h-terms". In this paper we benchmark the scheme in a number of demanding test problems] by including the relativistic generalizations of what are called "grad-h-terms" in non-relativistic SPH [32, 23

Rosswog, Stephan

199

Iterative springback compensation of NUMISHEET benchmark ?1  

NASA Astrophysics Data System (ADS)

Upon unloading after the forming stage, a sheet metal product will spring back due to internal stresses. Springback is a major problem for process-planning engineers. In industrial practise, deformations due to springback are compensated manually, by doing extensive measurements on prototype parts, and altering the tool geometry by hand. This is a time consuming and costly operation. In this paper the application of two compensation algorithms, based on the finite element simulation of the forming process are discussed. The smooth displacement adjustment (SDA) method and the springforward (SF) method have been applied to several industrial products, such as the NUMISHEET 2005 benchmark?1. With the SDA method successful compensations have been carried out. For the SF method some principal problems remain.

Lingbeek, R. A.; Hutink, J.; Ohnimus, S.; Weiher, J.

2005-08-01

200

Randomized benchmarking of multiqubit gates.  

PubMed

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 trap-a system that can in principle be scaled to larger numbers of ions. PMID:23004946

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

2012-06-29

201

Heat Pipe Technology  

NASA Technical Reports Server (NTRS)

The heat pipe, a sealed chamber whose walls are lined with a "wick," a thin capillary network containing a working fluid in liquid form was developed for a heat distribution system for non-rotating satellites. Use of the heat pipe provides a continuous heat transfer mechanism. "Heat tubes" that improve temperature control in plastics manufacturing equipment incorporated the heat pipe technology. James M. Stewart, an independent consultant, patented the heat tubes he developed and granted a license to Kona Corporation. The Kona Nozzle for heaterless injection molding gets heat for its operation from an external source and has no internal heating bands, reducing machine maintenance and also eliminating electrical hazards associated with heater bands. The nozzles are used by Eastman Kodak, Bic Pen Corporation, Polaroid, Tupperware, Ford Motor Company, RCA, and Western Electric in the molding of their products.

1981-01-01

202

Apparatus for inspecting piping  

DOEpatents

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.

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

1995-01-01

203

Heat-pipe Earth.  

PubMed

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

Moore, William B; Webb, A Alexander G

2013-09-26

204

Composite drill pipe  

DOEpatents

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.

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

205

Benchmarking Variable Cost Performance in an Industrial Power Plant  

E-print Network

BENCHMARKING VARIABLE COST PERFORMANCE IN AN INDUSTRIAL POWER PLANT John F. Kane, Jr., PE Consulting Engineer E. I. du Pont de Nemours and Company, Inc. Charlotte, North Carolina ABSTRACT One of the most perplexing problems... to meet this need that overcomes the problems discussed above and enables performance measurement over time. William F. Bailey Energy Technology Manager E. I. du Pont de Nemours and Company, Inc. Charlotte, North Carolina The "Energy Conversion...

Kane, J. F.; Bailey, W. F.

206

49 CFR 230.62 - Dry pipe.  

Code of Federal Regulations, 2010 CFR

...TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS...Appurtenances Steam Pipes 230.62 Dry pipe. Dry pipes subject to pressure...examined at each annual inspection to measure wall thickness. Dry pipes with wall...

2010-10-01

207

46 CFR 76.33-15 - Piping.  

Code of Federal Regulations, 2011 CFR

...Piping. (a) Individual pipes shall be not less than 3/4 -inch standard pipe size. (b) All piping...drainage. (e) Drains and dirt tapes shall be fitted where...prevent the accumulation of dirt or...

2011-10-01

208

46 CFR 76.33-15 - Piping.  

Code of Federal Regulations, 2010 CFR

...Piping. (a) Individual pipes shall be not less than 3/4 -inch standard pipe size. (b) All piping...drainage. (e) Drains and dirt tapes shall be fitted where...prevent the accumulation of dirt or...

2010-10-01

209

Tippy Tap Plus Piping  

NSDL National Science Digital Library

The Tippy Tap hand-washing station is an inexpensive and effective device used extensively in the developing world. One shortcoming of the homemade device is that it must be manually refilled with water and therefore is of limited use in high-traffic areas. In this activity, student teams design, prototype and test piping systems to transport water from a storage tank to an existing Tippy Tap hand-washing station, thereby creating a more efficient hand-washing station. Through this example service-learning engineering project, students learn basic fluid dynamic principles that are needed for creating efficient piping systems.

Integrated Teaching and Learning Program, College of Engineering, University of Colorado at Boulder,

210

Sustainable value assessment of farms using frontier efficiency benchmarks.  

PubMed

Appropriate assessment of firm sustainability facilitates actor-driven processes towards sustainable development. The methodology in this paper builds further on two proven methodologies for the assessment of sustainability performance: it combines the sustainable value approach with frontier efficiency benchmarks. The sustainable value methodology tries to relate firm performance to the use of different resources. This approach assesses contributions to corporate sustainability by comparing firm resource productivity with the resource productivity of a benchmark, and this for all resources considered. The efficiency is calculated by estimating the production frontier indicating the maximum feasible production possibilities. In this research, the sustainable value approach is combined with efficiency analysis methods to benchmark sustainability assessment. In this way, the production theoretical underpinnings of efficiency analysis enrich the sustainable value approach. The methodology is presented using two different functional forms: the Cobb-Douglas and the translog functional forms. The simplicity of the Cobb-Douglas functional form as benchmark is very attractive but it lacks flexibility. The translog functional form is more flexible but has the disadvantage that it requires a lot of data to avoid estimation problems. Using frontier methods for deriving firm specific benchmarks has the advantage that the particular situation of each company is taken into account when assessing sustainability. Finally, we showed that the methodology can be used as an integrative sustainability assessment tool for policy measures. PMID:19553001

Van Passel, Steven; Van Huylenbroeck, Guido; Lauwers, Ludwig; Mathijs, Erik

2009-07-01

211

Heat pipe array heat exchanger  

DOEpatents

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.

Reimann, Robert C. (Lafayette, NY)

1987-08-25

212

Pipe Drafting with CAD. Teacher Edition.  

ERIC Educational Resources Information Center

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

Smithson, Buddy

213

Heat pipe turbine vane cooling  

Microsoft Academic Search

The applicability of using heat pipe principles to cool gas turbine vanes is addressed in this beginning program. This innovative concept involves fitting out the vane interior as a heat pipe and extending the vane into an adjacent heat sink, thus transferring the vane incident heat transfer through the heat pipe to heat sink. This design provides an extremely high

L. Langston; A. Faghri

1995-01-01

214

Using Benchmarks to Compare Fractions  

NSDL National Science Digital Library

This task is intended primarily for instruction purposes. The goal is to provide examples for comparing two fractions. This is an important method for comparing fractions and one which requires a strong number sense and ability to make mental calculations. It is, however, a difficult ability to assess because the method is only appropriate when there is a clear benchmark fraction to be used.

IInstitute for Mathematics & Education funded by the Bill & Melinda Gates Foundation

2012-08-01

215

Austin Community College Benchmarking Update.  

ERIC Educational Resources Information Center

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

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

216

Benchmarking Adult Mental Health Organizations  

Microsoft Academic Search

Objective: This paper describes the adult mental health forums that were conducted as part of the National Mental Health Benchmarking Project (NMHBP).Method: Eight adult mental health forums were attended by staff from eight adult mental health services from around the country. The forums provided an avenue for these participants to document their organizations performances against previously agreed key performance indicators

Tim Coombs; Tania Geyer; Jane Pirkis

2011-01-01

217

Acme jumper pipe  

SciTech Connect

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.

Medved, P.; Thomas, H. [Acme Steel Co., Chicago, IL (United States)

1995-09-01

218

New CPU benchmark suites from SPEC  

Microsoft Academic Search

The author describes the new CPU benchmark suites from the Standard Performance Evaluation Corporation (SPEC). The author describes the reasons for the release, and analyzes and compares new suites with the SPEC Release 1 benchmark suite. The new benchmark CPU suites are CINT2.0 (integer) and CFP2.0 (floating-point). CINT2.0 and CFP2.0 replace the SPEC Release 1 benchmark suite. The new suites

Kaivalya M. Dixit

1992-01-01

219

How Benchmarking and Higher Education Came Together  

ERIC Educational Resources Information Center

This chapter introduces the concept of benchmarking and how higher education institutions began to use benchmarking for a variety of purposes. Here, benchmarking is defined as a strategic and structured approach whereby an organization compares aspects of its processes and/or outcomes to those of another organization or set of organizations to

Levy, Gary D.; Ronco, Sharron L.

2012-01-01

220

Benchmarking Gas Path Diagnostic Methods: A Public Approach  

NASA Technical Reports Server (NTRS)

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.

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

2008-01-01

221

Heat Pipes Cool Power Magnetics  

NASA Technical Reports Server (NTRS)

Configurations originally developed for space use are effective in any orientation. Heat pipes integrated into high-power, high-frequency, highvoltage spaceflight magnetics reduce weight and improve reliability by lowering internal tempertures. Two heat pipes integrated in design of power transformer cool unit in any orientation. Electrostatic shield conducts heat from windings to heat pipe evaporator. Technology allows dramatic reductions in size and weight, while significantly improving reliability. In addition, all attitude design of heat pipes allows operation of heat pipes independent of local gravity forces.

Hansen, I.; Chester, M.; Luedke, E.

1983-01-01

222

Transient Conjugated Forced Convection in Turbulent Pipe Flows  

Microsoft Academic Search

This work deals with the problem of transient conjugated forced convection heat transfer in turbulent pipe flows. The external surface of the pipe over a finite heated section is subjected to either uniform heat flux or uniform wall temperature. The governing parameters indentified in this work are the Reynolds number Re, the wall-to-fluid conductivity ratio K, the wall-to-fluid diffusivity ratio

Kuan-Tzong Lee; Wei-Mon Yan

1995-01-01

223

NAS Parallel Benchmark Results 11-96. 1.0  

NASA Technical Reports Server (NTRS)

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.

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

1997-01-01

224

OTEC cold-water pipe research  

Microsoft Academic Search

Shelf-mounted Ocean Thermal Energy Conversion (OTEC) plants require installation of cold-water pipes (CWP) on slopes of40degto depths of 1000 m. In addition, tower platforms containing OTEC power systems may be located on lesser sloped terrain near shore and exposed to special environmental loading problems affecting foundation design. Shelf-mounted installations require careful attention to site selection and geotechnical considerations for foundation

JOSEPH R. VADUS; BOB J. TAYLOR

1985-01-01

225

A numerical benchmark test for continuous casting of steel  

NASA Astrophysics Data System (ADS)

There is a continuously developing need for benchmarking of solidification simulations - from the theoretical as well as from the applied points of view. The benchmarking is usually done in two parts. The verification part confirms the proper numerical solution (Are we solving the equations correctly?) and the validation part (Are we solving the right equations?) confirms the proper response of the simulations regarding the experimental evidence. The history of related benchmarking shows differences of the results between different numerical methods, and differences in comparison with the experiments when solving even quite simple solidification situations. The present benchmark test proposes the verification benchmark for continuous casting of steel. Since the simulations of the temperatures, velocities, pressures and concentrations in the continuous casting represent a multiscale and multiphysics problem of high complexity (far away from a closed form solution), the verification can be done only by comparing the results of different numerical methods for solving the same governing equations. This has been done in the context of continuous casting by breaking the considered two dimensional problem into several sub problems by increasing complexity of geometry (straight in vertical direction, curved), boundary conditions (linear, non-linear), material properties (only Fe and Fe - C), microscopic considerations (Lever rule and Scheil rule). The governing equations complexity first involves only convective - diffusive heat transport with a predetermined velocity field, and assumed laminar and turbulent velocity calculations afterwards, modelled by a low Reynolds number turbulence model. Further complications involve the presence of the electromagnetic forces. The paper represents guidelines for the presentation of the numerical method, discretisation and results, as well as some of the results, obtained by the commercial finite volume based code and our in-house meshless method based laboratory code.

arler, B.; Vertnik, R.; Mramor, K.

2012-07-01

226

HS06 Benchmark for an ARM Server  

NASA Astrophysics Data System (ADS)

We benchmarked an ARM cortex-A9 based server system with a four-core CPU running at 1.1 GHz. The system used Ubuntu 12.04 as operating system and the HEPSPEC 2006 (HS06) benchmarking suite was compiled natively with gcc-4.4 on the system. The benchmark was run for various settings of the relevant gcc compiler options. We did not find significant influence from the compiler options on the benchmark result. The final HS06 benchmark result is 10.4.

Kluth, Stefan

2014-06-01

227

HS06 Benchmark for an ARM Server  

E-print Network

We benchmarked an ARM cortex-A9 based server system with a four-core CPU running at 1.1 GHz. The system used Ubuntu 12.04 as operating system and the HEPSPEC 2006 (HS06) benchmarking suite was compiled natively with gcc-4.4 on the system. The benchmark was run for various settings of the relevant gcc compiler options. We did not find significant influence from the compiler options on the benchmark result. The final HS06 benchmark result is 10.4.

Stefan Kluth

2013-11-15

228

Benchmarking using the Community Atmospheric Model  

SciTech Connect

The Community Atmospheric Model (CAM) is a global atmosphere model developed for the weather and climate research communities. CAM also serves as the atmospheric component of the Community Climate System Model (CCSM). As a community model, it is important that CAM run efficiently on different architectures, and that it be easily ported to and optimized on new platforms. The current version of CAM contains a number of performance portability features- compile-time or runtime parameters that can be used to optimize performance for a given platform, problem or processor count. The large number of tuning options can make benchmarking an arduous task. The paper describes these options and how optimization is managed to make it feasible for evaluation of early systems. The paper also describes some of the performance sensitivities of selected

Worley, Patrick H [ORNL

2006-01-01

229

Weapons-grade MOX PWR benchmark calculations  

SciTech Connect

A simplified model of a Westinghouse pressurized water reactor (PWR) assembly has been proposed as a weapons-grade mixed-oxide (MOX) benchmark. The bundle design consists of a uniform plutonium loading that would be appropriate for a full MOX core. The benchmark consists of several state point calculations at zero burnup, a multicycle depletion to 45 MWd/kg, and several state point calculations at end of life. Calculations of the PWR MOX benchmark have been performed with the KENO Monte Carlo code and the VENTURE diffusion theory code using cross sections created using the SCALE system and with the HELIOS system. The benchmark has been proposed as a light water reactor MOX benchmark with initial results being submitted by the participants by September 1998. The complete specifications for the benchmark are available at http://www.engr.utk.edu/org/ans/benchmark/ansmoxbm.html.

Gehin, J.C. [Oak Ridge National Lab., TN (United States)

1998-12-31

230

No free lunch and benchmarks.  

PubMed

We extend previous results concerning black box search algorithms, presenting new theoretical tools related to no free lunch (NFL) where functions are restricted to some benchmark (that need not be permutation closed), algorithms are restricted to some collection (that need not be permutation closed) or limited to some number of steps, or the performance measure is given. Minimax distinctions are considered from a geometric perspective, and basic results on performance matching are also presented. PMID:22452316

Duez-Guzmn, Edgar A; Vose, Michael D

2013-01-01

231

Benchmarking Electricity Liberalisation in Europe  

E-print Network

sources does the countrys electricity industry use? A country with a high proportion of hydro-electricity may not be exposed to fluctuations in the prices of fossil fuels, but is vulnerable to years with low precipitation. Historically, oil prices have... that the method of allocating inter- connector capacity is suitable for benchmarking. Since most countries in Europe have inter-connectors with several other countries, a possible summary statistic would be the proportion of their inter-connector capacity...

Green, Richard J; Lorenzoni, Arturo; Perez, Yannick; Pollitt, Michael G.

232

RISKIND verification and benchmark comparisons  

SciTech Connect

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.

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

1997-08-01

233

Guidable pipe plug  

DOEpatents

A plugging device for closing an opening defined by an end of a pipe with sealant comprises a cap, an extension, an inner seal, a guide, and at least one stop. The cap has an inner surface which defines a chamber adapted for retaining the sealant. The chamber is dimensioned slightly larger than the end so as to receive the end. The chamber and end define a gap therebetween. The extension has a distal end and is attached to the inner surface opposite the distal end. The inner seal is attached to the extension and sized larger than the opening. The guide is positioned forward of the inner seal and attached to the distal end. The guide is also dimensioned to be inserted into the opening. The stop is attached to the extender, and when the stop is disposed in the pipe, the stop is movable with respect to the conduit in one direction and also prevents misalignment of the cap with the pipe. A handle can also be included to allow the cap to be positioned robotically.

Glassell, Richard L. (Knoxville, TN); Babcock, Scott M. (Farragut, TN); Lewis, Benjamin E. (Farragut, TN)

2001-01-01

234

Pipe inspection using the pipe crawler. Innovative technology summary report  

SciTech Connect

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.

NONE

1999-05-01

235

Experimenting with a ``Pipe'' Whistle  

NASA Astrophysics Data System (ADS)

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.

Stafford, Olga

2012-04-01

236

Benchmark programs for evaluating knowledge-based performance requirements  

Microsoft Academic Search

A set of benchmark programs that have many of the characteristics of full-sized, complex knowledge-based systems are presented. They are: Weaver, a VLSI routing program; Rubik, which solves the Rubik's cube problem; Tourney, which assigns match schedules for a tournament; and Big Conflict, a program designed to stress the Rete matching algorithm. A methodology for characterizing knowledge-based system software and

M. M. Hayes; K. L. Ruoff

1990-01-01

237

A biosegmentation benchmark for evaluation of bioimage analysis methods  

PubMed Central

Background We present a biosegmentation benchmark that includes infrastructure, datasets with associated ground truth, and validation methods for biological image analysis. The primary motivation for creating this resource comes from the fact that it is very difficult, if not impossible, for an end-user to choose from a wide range of segmentation methods available in the literature for a particular bioimaging problem. No single algorithm is likely to be equally effective on diverse set of images and each method has its own strengths and limitations. We hope that our benchmark resource would be of considerable help to both the bioimaging researchers looking for novel image processing methods and image processing researchers exploring application of their methods to biology. Results Our benchmark consists of different classes of images and ground truth data, ranging in scale from subcellular, cellular to tissue level, each of which pose their own set of challenges to image analysis. The associated ground truth data can be used to evaluate the effectiveness of different methods, to improve methods and to compare results. Standard evaluation methods and some analysis tools are integrated into a database framework that is available online at . Conclusion This online benchmark will facilitate integration and comparison of image analysis methods for bioimages. While the primary focus is on biological images, we believe that the dataset and infrastructure will be of interest to researchers and developers working with biological image analysis, image segmentation and object tracking in general. PMID:19878606

Drelie Gelasca, Elisa; Obara, Boguslaw; Fedorov, Dmitry; Kvilekval, Kristian; Manjunath, BS

2009-01-01

238

Jamaican red clay tobacco pipes  

E-print Network

of Department) December 1992 ABSTRACT Jamaican Red Clay Tobacco Pipes. (December 1992) Kenan Paul Heidtke, B. A. , Texas Lutheran College Chair of Advisory Committee: Dr. D. L. Hamilton This thesis is a study of the red clay tobacco pipes which are found... with a special emphasis on pipes recovered from the important English colonial city of Port Royal. Until it was almost totally destroyed by an earthquake in 1692, Port Royal was the most important English city in the Caribbean. The goals...

Heidtke, Kenan Paul

2012-06-07

239

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

SciTech Connect

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.

Oswald, K.J. [Smith Fiberglass Products Inc., Little Rock, AR (United States)

1996-05-01

240

Multileg Heat-Pipe Evaporator  

NASA Technical Reports Server (NTRS)

Parallel pipes provide high heat flow from small heat exchanger. Six parallel heat pipes extract heat from overlying heat exchanger, forming evaporator. Vapor channel in pipe contains wick that extends into screen tube in liquid channel. Rods in each channel hold wick and screen tube in place. Evaporator compact rather than extended and more compatible with existing heat-exchanger geometries. Prototype six-pipe evaporator only 0.3 m wide and 0.71 m long. With ammonia as working fluid, transports heat to finned condenser at rate of 1,200 W.

Alario, J. P.; Haslett, R. A.

1986-01-01

241

Thermostructural applications of heat pipes  

NASA Technical Reports Server (NTRS)

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.

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

1979-01-01

242

Seismic control of benchmark cable-stayed bridge using passive hybrid systems  

Microsoft Academic Search

Earthquake response of benchmark cable-stayed bridge with passive hybrid control systems is investigated. The passive hybrid system consists of high damping rubber bearing, lead-rubber bearing, friction pendulum system and resilient-friction base isolator (R-FBI) supplemented with the linear and non-linear viscous fluid damper (VFD). Considering the phase-I benchmark problem, the ground acceleration is only applied in the longitudinal direction acting simultaneously

Purnachandra Saha; R. S. Jangid

2009-01-01

243

Adapting the SPEC 2000 Benchmark Suite for Simulation-Based Computer Architecture Research  

Microsoft Academic Search

\\u000a The large input datasets in the SPEC 2000 benchmark suite result in unreasonably long simulation times when using detailed\\u000a execution-driven simulators for evaluating future computer architecture ideas. To address this problem, we have an ongoing\\u000a project to reduce the execution times of the SPEC 2000 benchmarks in a quantitatively defensible way. Upon completion of this\\u000a work1, we will have smaller

AJ KleinOsowski; John Flynn; Nancy Meares; David J. Lilja

244

Gaia FGK benchmark stars: Metallicity  

NASA Astrophysics Data System (ADS)

Context. To calibrate automatic pipelines that determine atmospheric parameters of stars, one needs a sample of stars, or "benchmark stars", with well-defined parameters to be used as a reference. Aims: We provide detailed documentation of the iron abundance determination of the 34 FGK-type benchmark stars that are selected to be the pillars for calibration of the one billion Gaia stars. They cover a wide range of temperatures, surface gravities, and metallicities. Methods: Up to seven different methods were used to analyze an observed spectral library of high resolutions and high signal-to-noise ratios. The metallicity was determined by assuming a value of effective temperature and surface gravity obtained from fundamental relations; that is, these parameters were known a priori and independently from the spectra. Results: We present a set of metallicity values obtained in a homogeneous way for our sample of benchmark stars. In addition to this value, we provide detailed documentation of the associated uncertainties. Finally, we report a value of the metallicity of the cool giant ? Phe for the first time. Based on NARVAL and HARPS data obtained within the Gaia DPAC (Data Processing and Analysis Consortium) and coordinated by the GBOG (Ground-Based Observations for Gaia) working group and on data retrieved from the ESO-ADP database.Tables 6-76 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/564/A133

Jofr, P.; Heiter, U.; Soubiran, C.; Blanco-Cuaresma, S.; Worley, C. C.; Pancino, E.; Cantat-Gaudin, T.; Magrini, L.; Bergemann, M.; Gonzlez Hernndez, J. I.; Hill, V.; Lardo, C.; de Laverny, P.; Lind, K.; Masseron, T.; Montes, D.; Mucciarelli, A.; Nordlander, T.; Recio Blanco, A.; Sobeck, J.; Sordo, R.; Sousa, S. G.; Tabernero, H.; Vallenari, A.; Van Eck, S.

2014-04-01

245

Benchmarking for the competitive marketplace.  

PubMed

One would get little argument these days regarding the importance of performance measurement in the health care industry. The traditional approach has been the straightforward use of measurable units such as financial comparisons and clinical indicators (e.g., length of stay). Also we in the health care industry have traditionally benchmarked our performance and strategies against those most like ourselves. Today's competitive market demands a more customer-focused set of performance measures that go beyond traditional approaches such as customer service. The most important task in today's environment is to study the customers' emerging priorities and adjust our business to meet those priorities. PMID:11184882

Clarke, R W; Sucher, T O

1999-07-01

246

Heat Pipe Technology for Energy Conservation in the Process Industry  

E-print Network

corrosion or soot buildup posed a problem. But since an alternate fuel could be selected at a later date, plain solid fins were chosen at a spacing of 4 fins per inch. The boiler employs seven rows of carbon steel heat pipes to recover heat... corrosion or soot buildup posed a problem. But since an alternate fuel could be selected at a later date, plain solid fins were chosen at a spacing of 4 fins per inch. The boiler employs seven rows of carbon steel heat pipes to recover heat...

Price, B. L. Jr.

247

49 CFR 236.712 - Brake pipe.  

Code of Federal Regulations, 2010 CFR

... 2010-10-01 false Brake pipe. 236.712 Section 236.712...INSTRUCTIONS GOVERNING THE INSTALLATION, INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL...Definitions 236.712 Brake pipe. A pipe running from the engineman's...

2010-10-01

248

14 CFR 29.1123 - Exhaust piping.  

Code of Federal Regulations, 2011 CFR

...Exhaust System 29.1123 Exhaust piping. (a) Exhaust piping must be heat and corrosion resistant, and must have provisions to prevent failure due to expansion by operating temperatures. (b) Exhaust piping must be supported to...

2011-01-01

249

14 CFR 29.1123 - Exhaust piping.  

Code of Federal Regulations, 2010 CFR

...Exhaust System 29.1123 Exhaust piping. (a) Exhaust piping must be heat and corrosion resistant, and must have provisions to prevent failure due to expansion by operating temperatures. (b) Exhaust piping must be supported to...

2010-01-01

250

14 CFR 27.1123 - Exhaust piping.  

Code of Federal Regulations, 2011 CFR

...Exhaust System 27.1123 Exhaust piping. (a) Exhaust piping must be heat and corrosion resistant, and must have provisions to prevent failure due to expansion by operating temperatures. (b) Exhaust piping must be supported to...

2011-01-01

251

14 CFR 27.1123 - Exhaust piping.  

Code of Federal Regulations, 2010 CFR

...Exhaust System 27.1123 Exhaust piping. (a) Exhaust piping must be heat and corrosion resistant, and must have provisions to prevent failure due to expansion by operating temperatures. (b) Exhaust piping must be supported to...

2010-01-01

252

The Zoo, Benchmarks & You: How To Reach the Oregon State Benchmarks with Zoo Resources.  

ERIC Educational Resources Information Center

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)

2002

253

Establishing benchmarks and metrics for utilization management.  

PubMed

The changing environment of healthcare reimbursement is rapidly leading to a renewed appreciation of the importance of utilization management in the clinical laboratory. The process of benchmarking of laboratory operations is well established for comparing organizational performance to other hospitals (peers) and for trending data over time through internal benchmarks. However, there are relatively few resources available to assist organizations in benchmarking for laboratory utilization management. This article will review the topic of laboratory benchmarking with a focus on the available literature and services to assist in managing physician requests for laboratory testing. PMID:24095835

Melanson, Stacy E F

2014-01-01

254

Method and system for benchmarking computers  

DOEpatents

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.

Gustafson, John L. (Ames, IA)

1993-09-14

255

Benchmarks for acute stroke care delivery  

PubMed Central

Objective Despite widespread interest in many jurisdictions in monitoring and improving the quality of stroke care delivery, benchmarks for most stroke performance indicators have not been established. The objective of this study was to develop data-derived benchmarks for acute stroke quality indicators. Design Nine key acute stroke quality indicators were selected from the Canadian Stroke Best Practice Performance Measures Manual. Participants A population-based retrospective sample of patients discharged from 142 hospitals in Ontario, Canada, between 1 April 2008 and 31 March 2009 (N = 3191) was used to calculate hospital rates of performance and benchmarks. Intervention The Achievable Benchmark of Care (ABC) methodology was used to create benchmarks based on the performance of the upper 15% of patients in the top-performing hospitals. Main Outcome Measures Benchmarks were calculated for rates of neuroimaging, carotid imaging, stroke unit admission, dysphasia screening and administration of stroke-related medications. Results The following benchmarks were derived: neuroimaging within 24 h, 98%; admission to a stroke unit, 77%; thrombolysis among patients arriving within 2.5 h, 59%; carotid imaging, 93%; dysphagia screening, 88%; antithrombotic therapy, 98%; anticoagulation for atrial fibrillation, 94%; antihypertensive therapy, 92% and lipid-lowering therapy, 77%. ABC acute stroke care benchmarks achieve or exceed the consensus-based targets required by Accreditation Canada, with the exception of dysphagia screening. Conclusions Benchmarks for nine hospital-based acute stroke care quality indicators have been established. These can be used in the development of standards for quality improvement initiatives. PMID:24141011

Hall, Ruth E.; Khan, Ferhana; Bayley, Mark T.; Asllani, Eriola; Lindsay, Patrice; Hill, Michael D.; O'Callaghan, Christina; Silver, Frank L.; Kapral, Moira K.

2013-01-01

256

Vapor spill pipe monitor  

DOEpatents

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.

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

1983-06-23

257

SWEB. Scientific Workstation Evaluation Benchmark  

SciTech Connect

The SCIENTIFIC WORKSTATION EVALUATION BENCHMARK software includes 16 programs which are executed in a well-defined scenario to measure the following performance capabilities of a scientific workstation: implementation of FORTRAN77, processor speed, memory management, disk I/O, monitor (or display) output, scheduling of processing (multiprocessing), and scheduling of print tasks (spooling). The benchmark programs are: DK1, DK2, and DK3, which do Fourier series fitting based on spline techniques; JC1, which checks the FORTRAN function routines which produce numerical results; JD1 and JD2, which solve dense systems of linear equations in double and single-precision, respectively; JD3 and JD4, which perform matrix multiplication in single and double-precision, respectively; RB1, RB2, and RB3, which perform substantial amounts of I/O processing on files other than the input and output files; RR1, which does intense single-precision floating-point multiplication in a tight loop; RR2, which initializes a 512x512 integer matrix in a manner which skips around in the address space rather than initializing each consecutive memory cell in turn; RR3, which writes alternating text buffers to the output file; RR4, which evaluates the timer routines and demonstrates that they conform to the specification; and RR5, which determines whether the workstation is capable of executing a 4-megabyte program.

Raffenetti, R.C. [Argonne National Lab., IL (United States)

1992-03-02

258

Pynamic: the Python Dynamic Benchmark  

SciTech Connect

Python is widely used in scientific computing to facilitate application development and to support features such as computational steering. Making full use of some of Python's popular features, which improve programmer productivity, leads to applications that access extremely high numbers of dynamically linked libraries (DLLs). As a result, some important Python-based applications severely stress a system's dynamic linking and loading capabilities and also cause significant difficulties for most development environment tools, such as debuggers. Furthermore, using the Python paradigm for large scale MPI-based applications can create significant file IO and further stress tools and operating systems. In this paper, we present Pynamic, the first benchmark program to support configurable emulation of a wide-range of the DLL usage of Python-based applications for large scale systems. Pynamic has already accurately reproduced system software and tool issues encountered by important large Python-based scientific applications on our supercomputers. Pynamic provided insight for our system software and tool vendors, and our application developers, into the impact of several design decisions. As we describe the Pynamic benchmark, we will highlight some of the issues discovered in our large scale system software and tools using Pynamic.

Lee, G L; Ahn, D H; de Supinksi, B R; Gyllenhaal, J C; Miller, P J

2007-07-10

259

Pipe crawler with stabilizing midsection  

SciTech Connect

This invention is comprised of a pipe crawler 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.

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

1993-09-20

260

Alternate high capacity heat pipe  

NASA Technical Reports Server (NTRS)

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.

Voss, F. E.

1986-01-01

261

Water flows from slotted pipes  

SciTech Connect

Results of experiments and analyses that determine jet flow distribution from slotted pipes of dimensions typical for OC-OTEC evaporators or condensers are described. For a pipe with a 6.3-cm inside diameter and 0.64-cm wide slot, the measured and predicted jet flow was low and nearly parallel to the pipe at the entrance, and high and perpendicular to the pipe only near the closed end. Slot lengths ranged from 1.5 m to 4.6 m, and inlet flow rates varied from 6 kg/s to 17 kg/s. Friction reduces the pressure in the entrance and intermediate portions of the pipe, while the rapidly decelerating flow produces high pressure recovery as it approaches the closed end. In the region of high flow next to the closed end, the ratio of slot area (slot length times width) to pipe cross-sectional area is less than two. To use a slotted pipe for generating falling jets in an OC-OTEC plant, the slot length should be 1 m or less (for a pipe with a 6.3-cm inside diameter and a 0.64-cm wide slot).

Olson, D.A.

1981-04-01

262

Pipe crawler with stabilizing midsection  

DOEpatents

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.

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

1994-01-01

263

Pipe crawler with stabilizing midsection  

DOEpatents

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.

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

1994-12-27

264

Mutual Fund Performance Evaluation: A Comparison of Benchmarks and Benchmark Comparisons  

Microsoft Academic Search

Our primary goal in this paper is to ascertain whether the absolute and relative rankings of managed funds are sensitive to the benchmark chosen to measure normal performance. We employ the standard CAPM benchmarks and a variety of APT benchmarks to investigate this question. We found that there is little similarity between the absolute and relative mutual fund rankings obtained

Bruce N. Lehmann; David M. Modest

1987-01-01

265

The anti-slurry erosion properties of polyethylene for sewerage pipe use  

Microsoft Academic Search

Sewerage systems are more common in Japan. The pipes and fittings in the systems are exposed not only to a corrosive environment, but also to the impact by solid particles contained in mud drains, resulting in an erosive wear on the surface. A strategy for coping with these problems involves replacing the more traditionally used iron and steel pipes with

Akihiro Yabuki; Kohjiro Sugita; Masanobu Matsumura; Masao Hirashima; Masayuki Tsunaga

2000-01-01

266

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...

267

Dynamic stability of a pipe conveying fluid with an uncertain computational model  

E-print Network

-strings and heat exchangers. See, for instance, Ritto et al. (2009) for nonlinear dynamics of a drillDynamic stability of a pipe conveying fluid with an uncertain computational model T. G. Rittoa , C deals with the problem of a pipe conveying fluid of interest in several engineering applications

Paris-Sud XI, Université de

268

Iron release from corroded iron pipes in drinkingwater distribution systems: effect of dissolved oxygen  

Microsoft Academic Search

Iron release from corroded iron pipes is the principal cause of ''colored water'' problems in drinkingwater distribution systems. The corrosion scales present in corroded iron pipes restrict the flow of water, and can also deteriorate the water quality. This research was focused on understandingthe effect of dissolved oxyg en (DO), a key water quality parameter, on iron release from the

P. Sarina; V. L. Snoeyink; J. Bebee; K. K. Jim; W. M. Krivena Beckett; J. A. Clement

269

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

NASA Technical Reports Server (NTRS)

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.

Eninger, J. E.

1974-01-01

270

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

SciTech Connect

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.

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

1982-06-01

271

Prometheus Hot Leg Piping Concept  

NASA Astrophysics Data System (ADS)

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.

Gribik, Anastasia M.; DiLorenzo, Peter A.

2007-01-01

272

Flexible ultrasonic pipe inspection apparatus  

DOEpatents

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.

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

1998-01-01

273

Transient flows and pressure waves in pipes  

NASA Astrophysics Data System (ADS)

Transient laminar flows and pressure-wave propagations in pipes connected with components, commonly known as water hammer, are analyzed. The system studied consists of a constant-pressure vessel, a uniform circular pipe, a valve between them, and a receiver vessel. A pressure-wave equation and a linearized velocity equation are derived from the equations of mass and momentum conservation. Waveform distortion due to viscous dissipation and pipe-wall elastic expansion is characterized by a dimensionless transmission number, K. The coefficients of the damping of the pressure waves were found to be related to the roots of the Bessel function J(sub 0). An exact solution of the pressure-wave equation was obtained numerically. The relationship between the distortion of a traveling wave and the transmission number K was studied. The problem is also calculated with a general-purpose computer code, COMMIX, which solves the exact mass conservation equation and Navier-Stokes equations. The COMMIX calculational results agreed well with the analytical solutions.

Wang, X. Q.; Sun, J. G.; Sha, W. T.

274

Steady flow in a dividing pipe  

NASA Astrophysics Data System (ADS)

The high Reynolds number flow through a circular pipe divided along a diameter by a semi-infinite splitter plate is considered. Matched asymptotic expansions are used to analyse the developing flow, which is decomposed into four regions: a boundary layer of Blasius type growing along the plate, an inviscid core, a viscous layer close to the curved wall and a nonlinear corner region. The core solution is found numerically, initially in the long-distance down-pipe limit and thereafter the full problem is solved using down-pipe Fourier transforms. The accuracy in the corners of the semicircular cross-section is improved by subtracting out the singularity in the velocity perturbation. The linear viscous wall layer is solved analytically in terms of a displacement function determined from the core. A plausible structure for the corner region and equations governing the motion therein are presented although no solution is attempted. The presence of the plate has little effect ahead of the bifurcation, but wall shear on the curved wall is found to increase from its undisturbed value downstream.

Blyth, M. G.; Mestel, A. J.

1999-12-01

275

Transient flows and pressure waves in pipes  

SciTech Connect

Transient laminar flows and pressure-wave propagations in pipes connected with components, commonly known as water hammer, are analyzed. The system studied consists of a constant-pressure vessel, a uniform circular pipe, a valve between them, and a receiver vessel. A pressure-wave equation and a linearized velocity equation are derived from the equations of mass and momentum conservation. Waveform distortion due to viscous dissipation and pipe-wall elastic expansion is characterized by a dimensionless transmission number, K. The coefficients of the damping of the pressure waves were found to be related to the roots of the Bessel function J{sub 0}. An exact solution of the pressure-wave equation was obtained numerically. The relationship between the distortion of a traveling wave and the transmission number K was studied. The problem is also calculated with a general-purpose computer code, COMMIX, which solves the exact mass conservation equation and Navier-Stokes equations. The COMMIX calculational results agreed well with the analytical solutions.

Wang, X.Q.; Sun, J.G.; Sha, W.T.

1994-06-01

276

Decontamination and decommissioning of small-bore pipe  

SciTech Connect

The ability to aggressively decontaminate to U.S. Nuclear Regulatory Commission (NRC) free-release limits, verify the effectiveness, and prove releasability of contaminated piping systems are tasks that became a major concern for Westinghouse during the Fort St. Vrain (FSV) decommissioning project. The problem is especially acute for small-bore piping systems [2.5- to 7.6-cm (1- to 3-in.) diameter] with multiple elbows. Westinghouse, and its wholly owned subsidiary, Scientific Ecology Group, being one of the two primary contractors for decommissioning the FSV nuclear generating station [330-MW(electric) high-temperature gas-cooled reactor, operated from 1979 to 1989], encountered this problem and developed equipment and methodologies to successfully decontaminate, survey, and decommission this piping.

Hackmann, E.K. [Westinghouse Electric Corp., Platteville, CO (United States)

1996-12-31

277

Benchmarking of collision operators with momentum source corrections  

SciTech Connect

Several linearized collision operator models with parallel momentum conservation enforced by source functions are benchmarked against the correct collision operator based on Rosenbluth potentials. The model operators without energy diffusion allow for an analytic solution of a generalized Spitzer problem. For the other operators under investigation, an integrodifferential equation is solved. The benchmarking is performed both for the parallel conductivity with the ions assumed at rest and for the bootstrap current, where ion and electron flows are collisionally coupled. The accuracy of the results obtained with the operators varies from rather poor in the case of the simplest monoenergetic model to quite satisfactory for the models employing an energy-weighted parallel momentum source function.

Maassberg, H.; Beidler, C. D. [EURATOM Association, Max-Planck-Institut fuer Plasmaphysik, D-17491 Greifswald (Germany)

2010-05-15

278

Calculation of the weapons-grade MOX VVER multiassembly benchmarks  

SciTech Connect

Within the framework of the joint US-Russian fissile materials disposition program, a set of VVER benchmarks was formulated to verify and validate computer codes with reference to the problem of using mixed-oxide (MOX) fuel in VVER reactors. This set consists of pin cell, single assembly, and multiassembly geometries with low-enriched uranium (LEU) and weapons-grade MOX fuel. Multiassembly geometries (variants V13 and V14) are of the most interest because they give information about an accuracy of neutron flux distribution calculation near the boundary between MOX and LEU. In this analysis, a uniform MOX bundle and a graded MOX bundle are studied. Benchmark calculations are performed for several states and for a depletion to 60 MWd/kg. The report is devoted to an intercomparison of calculation results for such geometries obtained with various codes.

Kalugin, M.A.; Lazarenko, A.P. [Kurchatov RRC (Russian Federation); Kalashnikov, A.G. [IPPE (Russian Federation); Gehin, J.C. [Oak Ridge National Lab., TN (United States)

1998-12-31

279

The effect of 25 years of oil field flow line service on epoxy fiberglass pipe  

SciTech Connect

Glass fiber-reinforced epoxy and vinyl ester piping systems have been used for more than 35 years to control corrosion problems in oil fields and chemical and industrial plants. Many case histories have documented successful performances of fiberglass-reinforced thermosetting plastics in a wide range of corrosive services. This information is reinforced by laboratory test data from flat laminates and pipe exposed to numerous chemicals and mixtures of chemicals, but little has been published to document the effect of long-term, in-service exposure on fiberglass equipment. This paper compares data from physical testing of pipe removed from successful corrosive service applications with data obtained from the same type of pipe at the time of manufacture. The information supplied in these papers represents only a few of the successful applications of filament wound epoxy and vinyl ester pipe because it is difficult to obtain permission to remove pipe from an operating line.

Oswald, K.J.

1988-08-01

280

Avoiding steam bubble collapse-induced water hammer in the auxiliary piping of steam power plants  

SciTech Connect

The mechanisms of steam bubble collapse-induced water hammer are identified for nominally horizontal or inclined pipes. On the basis of these observations, two methods of preventing steam bubble collapse-induced water hammer in nominally horizontal pipes are proposed. They are inclining them and injecting the water at a controlled rate at either the lowest point or injecting the water at several locations. The success of these methods is demonstrated for horizontal pipes and for pipes of other orientations. These ways of preventing steam bubble collapse-induced water hammer are then used to test filling strategies for L''-shaped pipes oriented in practically every way. Both methods are found to work though the application of multiple injection ports and has complications when applied to a complex piping system. The use of the recommended design guidelines for avoiding steam bubble collapse-induced water hammer is demonstrated in an example problem.

Lobo, C.A.O.C. (COPESP, Sao Paulo (Brazil)); Griffith, P. (Massachusetts Inst. of Tech., Cambridge, MA (United States))

1994-02-01

281

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

SciTech Connect

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.

Oswald, K.J. [Smith Fiberglass Products Inc., Little Rock, AR (United States)

1995-10-01

282

Shielding Integral Benchmark Archive and Database (SINBAD)  

Microsoft Academic Search

The Shielding Integral Benchmark Archive and Database (SINBAD) collection of benchmarks was initiated in the early 1990s. SINBAD is an international collaboration between the Organization for Economic Cooperation and Development's Nuclear Energy Agency Data Bank (OECD\\/NEADB) and the Radiation Safety Information Computational Center (RSICC) at Oak Ridge National Laboratory (ORNL). SINBAD is a major attempt to compile experiments and corresponding

Bernadette Lugue Kirk; Robert E Grove; I. Kodeli; Enrico Sartori; J. Gulliford

2011-01-01

283

Beyond Benchmarking: Value-Adding Metrics  

ERIC Educational Resources Information Center

HR metrics has grown up a bit over the past two decades, moving away from simple benchmarking practices and toward a more inclusive approach to measuring institutional performance and progress. In this article, the acknowledged "father" of human capital performance benchmarking provides an overview of several aspects of today's HR metrics

Fitz-enz, Jac

2007-01-01

284

Benchmarking Learning and Teaching: Developing a Method  

ERIC Educational Resources Information Center

Purpose: To develop a method for benchmarking teaching and learning in response to an institutional need to validate a new program in Dentistry at the University of Sydney, Australia. Design/methodology/approach: After a collaborative partner, University of Adelaide, was identified, the areas of teaching and learning to be benchmarked, PBL

Henderson-Smart, Cheryl; Winning, Tracey; Gerzina, Tania; King, Shalinie; Hyde, Sarah

2006-01-01

285

International Benchmarking of Vocational Education and Training  

ERIC Educational Resources Information Center

This report critically examines two approaches to benchmarking vocational education and training (VET) - benchmarking through performance indicators and comparative case studies. The author finds both approaches provide useful information, although the case study approach enables a more thorough analysis of particular issues and can take greater

Wyatt, Tim

2004-01-01

286

Introduction to the HPC Challenge Benchmark Suite  

Microsoft Academic Search

The HPC Challenge benchmark suite has been released by the DARPA HPCS program to help define the performance boundaries of future Petascale computing systems. HPC Challenge is a suite of tests that examine the performance of HPC architectures using kernels with memory access patterns more challenging than those of the High Performance Linpack (HPL) benchmark used in the Top500 list.

Piotr Luszczek; Jack J. Dongarra; David Koester; Rolf Rabenseifner; Bob Lucas; Jeremy Kepner; John McCalpin; David Bailey; Daisuke Takahashi

2005-01-01

287

Best practice benchmarking: a route to competitiveness?  

Microsoft Academic Search

This paper examines the use of best practice benchmarking as an approach to performance improvement in the airline industry. The case study draws upon phenomenological evidence from the aircraft maintenance section of Britannia Airways. A range of benchmarking issues, which could be applied to different divisions of an airline are highlighted. In particular, inter disciplinary team building, employee involvement, relationships

Graham Francis; Matthew Hinton; Jacky Holloway; Ian Humphreys

1999-01-01

288

Rodinia: A benchmark suite for heterogeneous computing  

Microsoft Academic Search

This paper presents and characterizes Rodinia, a benchmark suite for heterogeneous computing. To help architects study emerging platforms such as GPUs (Graphics Processing Units), Rodinia includes applications and kernels which target multi-core CPU and GPU platforms. The choice of applications is inspired by Berkeley's dwarf taxonomy. Our characterization shows that the Rodinia benchmarks cover a wide range of parallel communication

Shuai Che; Michael Boyer; Jiayuan Meng; David Tarjan; Jeremy W. Sheaffer; Sang-ha Lee; Kevin Skadron

2009-01-01

289

Benchmarking Helps Measure Union Programs, Operations.  

ERIC Educational Resources Information Center

Explores three examples of benchmarking by college student unions. Focuses on how a union can collect information from other unions for use as benchmarking standards for the purposes of selling a concept or justifying program increases, or for comparing a union's financial performance to other unions. (EV)

Mann, Jerry

2001-01-01

290

Benchmarking Database Systems A Systematic Approach  

Microsoft Academic Search

This paper describes a customized database and a comprehensive set of queries that can be used for systematic benchmarking of relational database systems. Designing this database and a set of carefully tuned benchmarks represents a first attempt in developing a scientific methodology for performance evaluation of database management systems. We have used this database to perform a comparative evaluation of

Dina Bitton; David J. Dewitt; Carolyn Turbyfill

1983-01-01

291

A Simplified HTTR Diffusion Theory Benchmark  

Microsoft Academic Search

The Georgia Institute of Technology (GA-Tech) recently developed a transport theory benchmark based closely on the geometry and the features of the HTTR reactor that is operational in Japan. Though simplified, the benchmark retains all the principal physical features of the reactor and thus provides a realistic and challenging test for the codes. The purpose of this paper is twofold.

Rodolfo M. Ferrer; Abderrafi M. Ougouag; Farzad Rahnema

2010-01-01

292

DARPA February 1992 ATIS benchmark test results  

Microsoft Academic Search

This paper documents the third in a series of Benchmark Tests for the DARPA Air Travel Information System (ATIS) common task domain. The first results in this series were reported at the June 1990 Speech and Natural Language Workshop [1], and the second at the February 1991 Speech and Natural Language Workshop [2]. The February 1992 Benchmark Tests include: (1)

David S. Pallett; Nancy L. Dahlgren; Jonathan G. Fiscus; William M. Fisher; John S. Garofolo; Brett C. Tjaden

1992-01-01

293

Benchmarking Database Systems A Systematic Approach  

E-print Network

Benchmarking Database Systems A Systematic Approach Dina Bitton David J. DeWitt Carolyn Turbyfill-81ER10920. #12;ABSTRACT This paper describes a customized database and a comprehensive set of queries that can be used for sys- tematic benchmarking of relational database systems. Designing this database

Liblit, Ben

294

Experimental Study for Heat Transfer Characteristics of High Water-cooled Temperature Gas Pipe in Lignite Boiler  

Microsoft Academic Search

Recently, there are some problems like complex system, large weight of pumping high-temperature pipe and easily damaged heat preservation on three media desiccation of large scale fan mill direct firing pulverizing system. Directed towards these problems, adopting water-cooled high temperature furnace gas pipe to adjustment high gas temperature is proposed, to change three media desiccation into two media desiccation. Heat

Tai Lv; Yang Guo; Kun Lu

2010-01-01

295

Linear Road : benchmarking stream-based data management systems  

E-print Network

This thesis describes the design, implementation, and execution of the Linear Road benchmark for stream-based data management systems. The motivation for benchmarking and the selection of the benchmark application are ...

Tibbetts, Richard S. (Richard Singleton), 1979-

2003-01-01

296

Benchmarking ICRF simulations for ITER  

SciTech Connect

Abstract Benchmarking of full-wave solvers for ICRF simulations is performed using plasma profiles and equilibria obtained from integrated self-consistent modeling predictions of four ITER plasmas. One is for a high performance baseline (5.3 T, 15 MA) DT H-mode plasma. The others are for half-field, half-current plasmas of interest for the pre-activation phase with bulk plasma ion species being either hydrogen or He4. The predicted profiles are used by seven groups to predict the ICRF electromagnetic fields and heating profiles. Approximate agreement is achieved for the predicted heating power partitions for the DT and He4 cases. Profiles of the heating powers and electromagnetic fields are compared.

R. V. Budny, L. Berry, R. Bilato, P. Bonoli, M. Brambilla, R.J. Dumont, A. Fukuyama, R. Harvey, E.F. Jaeger, E. Lerche, C.K. Phillips, V. Vdovin, J. Wright, and members of the ITPA-IOS

2010-09-28

297

Benchmarking Multipacting Simulations in VORPAL  

SciTech Connect

We will present the results of benchmarking simulations run to test the ability of VORPAL to model multipacting processes in Superconducting Radio Frequency structures. VORPAL is an electromagnetic (FDTD) particle-in-cell simulation code originally developed for applications in plasma and beam physics. The addition of conformal boundaries and algorithms for secondary electron emission allow VORPAL to be applied to multipacting processes. We start with simulations of multipacting between parallel plates where there are well understood theoretical predictions for the frequency bands where multipacting is expected to occur. We reproduce the predicted multipacting bands and demonstrate departures from the theoretical predictions when a more sophisticated model of secondary emission is used. Simulations of existing cavity structures developed at Jefferson National Laboratories will also be presented where we compare results from VORPAL to experimental data.

C. Nieter, C. Roark, P. Stoltz, K. Tian

2009-05-01

298

NASA Software Engineering Benchmarking Study  

NASA Technical Reports Server (NTRS)

To identify best practices for the improvement of software engineering on projects, NASA's Offices of Chief Engineer (OCE) and Safety and Mission Assurance (OSMA) formed a team led by Heather Rarick and Sally Godfrey to conduct this benchmarking study. The primary goals of the study are to identify best practices that: Improve the management and technical development of software intensive systems; Have a track record of successful deployment by aerospace industries, universities [including research and development (R&D) laboratories], and defense services, as well as NASA's own component Centers; and Identify candidate solutions for NASA's software issues. Beginning in the late fall of 2010, focus topics were chosen and interview questions were developed, based on the NASA top software challenges. Between February 2011 and November 2011, the Benchmark Team interviewed a total of 18 organizations, consisting of five NASA Centers, five industry organizations, four defense services organizations, and four university or university R and D laboratory organizations. A software assurance representative also participated in each of the interviews to focus on assurance and software safety best practices. Interviewees provided a wealth of information on each topic area that included: software policy, software acquisition, software assurance, testing, training, maintaining rigor in small projects, metrics, and use of the Capability Maturity Model Integration (CMMI) framework, as well as a number of special topics that came up in the discussions. NASA's software engineering practices compared favorably with the external organizations in most benchmark areas, but in every topic, there were ways in which NASA could improve its practices. Compared to defense services organizations and some of the industry organizations, one of NASA's notable weaknesses involved communication with contractors regarding its policies and requirements for acquired software. One of NASA's strengths was its software assurance practices, which seemed to rate well in comparison to the other organizational groups and also seemed to include a larger scope of activities. An unexpected benefit of the software benchmarking study was the identification of many opportunities for collaboration in areas including metrics, training, sharing of CMMI experiences and resources such as instructors and CMMI Lead Appraisers, and even sharing of assets such as documented processes. A further unexpected benefit of the study was the feedback on NASA practices that was received from some of the organizations interviewed. From that feedback, other potential areas where NASA could improve were highlighted, such as accuracy of software cost estimation and budgetary practices. The detailed report contains discussion of the practices noted in each of the topic areas, as well as a summary of observations and recommendations from each of the topic areas. The resulting 24 recommendations from the topic areas were then consolidated to eliminate duplication and culled into a set of 14 suggested actionable recommendations. This final set of actionable recommendations, listed below, are items that can be implemented to improve NASA's software engineering practices and to help address many of the items that were listed in the NASA top software engineering issues. 1. Develop and implement standard contract language for software procurements. 2. Advance accurate and trusted software cost estimates for both procured and in-house software and improve the capture of actual cost data to facilitate further improvements. 3. Establish a consistent set of objectives and expectations, specifically types of metrics at the Agency level, so key trends and models can be identified and used to continuously improve software processes and each software development effort. 4. Maintain the CMMI Maturity Level requirement for critical NASA projects and use CMMI to measure organizations developing software for NASA. 5.onsolidate, collect and, if needed, develop common processes principles and other assets across t

Rarick, Heather L.; Godfrey, Sara H.; Kelly, John C.; Crumbley, Robert T.; Wifl, Joel M.

2013-01-01

299

Decay of Turbulence in Pipe Flow  

NASA Astrophysics Data System (ADS)

A novel experiment has been devised which provides direct evidence for critical point behavior in the longstanding problem of the transition to turbulence in a pipe. The novelty lies in the quenching of turbulence by reducing the Reynolds number and observing the decay of disordered motion. Divergence of the time scales implies underlying deterministic dynamics which are analogous to those found in boundary crises in dynamical systems. A modulated wave packet emerges from the long term transients and this coherent state provides evidence for connections with recent theoretical developments.

Peixinho, J.; Mullin, T.

2006-03-01

300

Light pipe - design for efficiency  

SciTech Connect

The high cost and availability of materials which are clear enough to transmit light without absorption has limited the idea of piping large-scale quantities of light. The light pipe uses the principle of Total Internal Reflection, with the light guided by very accurate prisms. The transmission of light directed into the end of a Light Pipe at an angle of less than 27.6 degrees is theoretically 100% efficient. The author describes its uses and advantages for lighting offices, cold storage areas, difficult access and hazardous areas, and for solar lighting. Future directions will be to improve the economics and accuracy of the technology. 4 references, 2 figures.

Hockey, S.N.

1985-08-01

301

Equations shorten pipe collapse calculations  

SciTech Connect

The API suggests collapse pressure equations for long, perfectly round, steel oil field casing, tubing, drill pipe, and line pipe. Operating and service company engineers can substitute two pipe collapse pressure equations for the 12 API equations now in general use. The shorthand results are almost the same as those from the API equations. The shorthand method has the additional advantage of allowing units from any measurement system. The API equations restrict calculations to US units only. The equation box lists the API (Equations 1--12) and the shorthand (Equations 13--14) equations. The API equations are based on work started shortly after the turn of the century.

Avakov, V.A. [Halliburton Energy Services, Duncan, OK (United States)

1995-04-10

302

Heat pipe transient response approximation.  

SciTech Connect

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.

Reid, R. S. (Robert Stowers)

2001-01-01

303

Variable conductance heat pipe technology  

NASA Technical Reports Server (NTRS)

Research and development programs in variable conductance heat pipe technology were conducted. The treatment has been comprehensive, involving theoretical and/or experimental studies in hydrostatics, hydrodynamics, heat transfer into and out of the pipe, fluid selection, and materials compatibility, in addition to the principal subject of variable conductance control techniques. Efforts were not limited to analytical work and laboratory experimentation, but extended to the development, fabrication and test of spacecraft hardware, culminating in the successful flight of the Ames Heat Pipe Experiment on the OAO-C spacecraft.

Marcus, B. D.; Edwards, D. K.; Anderson, W. T.

1973-01-01

304

A Heat Pipe Rankine engine  

NASA Astrophysics Data System (ADS)

The Heat Pipe Rankine (HPR) engine is a new concept for small scale power generation that uses heat and mass transport features of a heat pipe. A heat pipe is a heat transfer device in which heat is transferred efficiently from the evaporator section to the condenser section. Mechanical work is produced by a turbine placed in the vapor flowing between the evaporator and the condenser sections. As an external combustion engine, the HPR engine can utilize energy sources at various temperature levels and be adapted to different applications.

Chuah, Y. K.; Kreith, F.

1985-12-01

305

Turbulent-Laminar Patterns in Pipes and Channels  

Microsoft Academic Search

When fluid flows through a channel, pipe, or duct, there are two basic forms of motion: smooth laminar motion and complex turbulent motion. The discontinuous transition between these states is a fundamental problem that has been studied for more than 100 years. What has received far less attention is the large-scale nature of the turbulent flows near transition once they

Dwight Barkley

2010-01-01

306

Pipe defect characterisation by multi-sensor systems  

Microsoft Academic Search

Worldwide, pipeline systems differ in age, manufacture, length and system configuration. However, in all cases they require a large infrastructure investment, which for many cities and towns is one of their largest capital investments. Pipe leakage for these towns and cities can be a major problem, both from an environmental point of view, as well as the costs that are

M. Eiswirth; C. Heske; H. Htzl; T. Schneider; L. S. Burn

2000-01-01

307

Structural Response of Piping to Internal Gas Detonation  

Microsoft Academic Search

Detonation waves in gas-filled piping or tubing pose special challenges in analysis and prediction of structural response. The challenges arise due the nature of the detonation process and the role of fluid-structure interaction in determining the prop- agation and arrest of fractures. Over the past ten years, our laboratory has been engaged in studying this problem and devel- oping methodologies

Joseph E. Shepherd

2009-01-01

308

Axisymmetric Weakly Compressible Transient Pipe Flow and Water Hammer Control  

Microsoft Academic Search

Despite the partial success of existing theoretical models in explaining certain transient water flow phenomena in a long pipe, they can hardly predict the evolution of strong water hammer, in particular the one downstream the valve caused by its closing (reversed water hammer). We attack this important problem by a new perturbation theory based on the unsteady axisymmetric and compressible

Jie-Zhi Wu; Li-Jun Xuan; Feng Mao

2008-01-01

309

Decontaminating Aluminum/Ammonia Heat Pipes  

NASA Technical Reports Server (NTRS)

Internal gas slugs reduced or eliminated. Manufacturing method increases efficiency of aluminum heat pipes in which ammonia is working fluid by insuring pipe filled with nearly pure charge of ammonia. In new process heat pipe initially closed with stainless-steel valve instead of weld so pipe put through several cycles of filling, purging, and accelerated aging.

Jones, J. A.

1985-01-01

310

Page 1 of 1 Pipe School  

E-print Network

­ Rigid and Flexible Pipes: A comparison of rigid (concrete, clay, etc.) and flexible (steel, HDPE, PVC own) 1:00 PM Design and Construction Considerations for PVC Pipe: Everything you need to know about PVC pipe and its applications. John Houle, P.E., Uni-Bell PVC Pipe Association 1:45 Design

Huang, Haiying

311

Heat pipe technology: A biblography with abstracts  

NASA Technical Reports Server (NTRS)

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.

1972-01-01

312

Heat pipes and their technical applications  

Microsoft Academic Search

A general review paper on heat pipes is presented with attention given to principles of operation. Also considered are transfer processes in heat-pipe wicks, the effect of the structural characteristics of a wick on convective transfer of the working fluid, and heat and mass transfer in the wicks of low-temperature heat pipes. Applications of heat pipes in such fields as

L. L. Vasilev

1976-01-01

313

Heat pipe life and processing study  

NASA Technical Reports Server (NTRS)

The merit of adding water to the reflux charge in chemically and solvent cleaned aluminum/slab wick/ammonia heat pipes was evaluated. The effect of gas in the performance of three heat pipe thermal control systems was found significant in simple heat pipes, less significant in a modified simple heat pipe model with a short wickless pipe section. Use of gas data for the worst and best heat pipes of the matrix in a variable conductance heat pipe model showed a 3 C increase in the source temperature at full on condition after 20 and 246 years, respectively.

Antoniuk, D.; Luedke, E. E.

1979-01-01

314

Nitrogen heat pipe for cryocooler thermal shunt  

SciTech Connect

A nitrogen heat pipe was designed, built and tested for the purpose of providing a thermal shunt between the two stages of a Gifford-McMahan (GM) cryocooler during cooldown. The nitrogen heat pipe has an operating temperature range between 63 and 123 K. While the heat pipe is in the temperature range during the system cooldown, it acts as a thermal shunt between the first and second stage of the cryocooler. The heat pipe increases the heat transfer to the first stage of the cryocooler, thereby reducing the cooldown time of the system. When the heat pipe temperature drops below the triple point, the nitrogen working fluid freezes, effectively stopping the heat pipe operation. A small heat leak between cryocooler stages remains because of axial conduction along the heat pipe wall. As long as the heat pipe remains below 63 K, the heat pipe remains inactive. Heat pipe performance limits were measured and the optimum fluid charge was determined.

Prenger, F.C.; Hill, D.D.; Daney, D.E.; Daugherty, M.A. [Los Alamos National Lab., NM (United States); Green, G.F.; Roth, E.W. [Naval Surface Warfare Center, Annapolis, MD (United States)

1995-09-01

315

Corrugated pipe adhesive applicator apparatus  

DOEpatents

Apparatus for coating selected portions of the troughs of a corrugated pipe within 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.

Shirey, Ray A. (North Grafton, MA)

1983-06-14

316

Axial forces in piping systems  

SciTech Connect

This paper reviews the various pipe Code requirements related to control of axial forces in above ground piping systems. With the exception of ASME Section III (for seismic anchor motions) the Codes do not have specific limits for stresses induced by axial forces (F/A). These new limits will require changes to existing piping analysis computer programs. The present Code explicit limits on stresses due to bending moments result in implicit limits on axial stresses and associated axial forces. It is shown that the limitations of stresses in piping components due to bending moments result in corresponding conservative limits in stresses due to axial forces. Hence limits on axial forces are not required.

Wais, E.A. [Wais and Associates, Inc., Norcross, GA (United States)

1996-12-31

317

Heat Pipes: An Industrial Application  

E-print Network

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...

Murray, F.

1984-01-01

318

Developing integrated benchmarks for DOE performance measurement  

SciTech Connect

The objectives of this task were to describe and evaluate selected existing sources of information on occupational safety and health with emphasis on hazard and exposure assessment, abatement, training, reporting, and control identifying for exposure and outcome in preparation for developing DOE performance benchmarks. Existing resources and methodologies were assessed for their potential use as practical performance benchmarks. Strengths and limitations of current data resources were identified. Guidelines were outlined for developing new or improved performance factors, which then could become the basis for selecting performance benchmarks. Data bases for non-DOE comparison populations were identified so that DOE performance could be assessed relative to non-DOE occupational and industrial groups. Systems approaches were described which can be used to link hazards and exposure, event occurrence, and adverse outcome factors, as needed to generate valid, reliable, and predictive performance benchmarks. Data bases were identified which contain information relevant to one or more performance assessment categories . A list of 72 potential performance benchmarks was prepared to illustrate the kinds of information that can be produced through a benchmark development program. Current information resources which may be used to develop potential performance benchmarks are limited. There is need to develop an occupational safety and health information and data system in DOE, which is capable of incorporating demonstrated and documented performance benchmarks prior to, or concurrent with the development of hardware and software. A key to the success of this systems approach is rigorous development and demonstration of performance benchmark equivalents to users of such data before system hardware and software commitments are institutionalized.

Barancik, J.I.; Kramer, C.F.; Thode, Jr. H.C.

1992-09-30

319

Intermediate Temperature Water Heat Pipe Tests  

NASA Technical Reports Server (NTRS)

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.

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

2004-01-01

320

Intermediate Temperature Water Heat Pipe Tests  

NASA Technical Reports Server (NTRS)

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.

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

2005-01-01

321

Heat Pipe Thermal Conditioning Panel  

NASA Technical Reports Server (NTRS)

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.

Saaski, E. W.

1973-01-01

322

Mapping Temperatures On Heat Pipes  

NASA Technical Reports Server (NTRS)

Paints containing thermochromic liquid crystals (TLC's) used to map temperatures on heat pipes and thermosyphons. Color of thermally sensitive TLC coat changes reversibly upon heating or cooling. Each distinct color indicates particular temperature. Transient and steady-state isotherms become visible as colored bands. Positions and movements of bands yield information about startup transients, steady-state operation, cooler regions containing noncondensible gas, and other phenomena relevant to performance of heat pipe.

Gunnerson, Fred S.; Thorncroft, Glen E.

1993-01-01

323

Analytical Radiation Transport Benchmarks for The Next Century  

SciTech Connect

Verification of large-scale computational algorithms used in nuclear engineering and radiological applications is an essential element of reliable code performance. For this reason, the development of a suite of multidimensional semi-analytical benchmarks has been undertaken to provide independent verification of proper operation of codes dealing with the transport of neutral particles. The benchmarks considered cover several one-dimensional, multidimensional, monoenergetic and multigroup, fixed source and critical transport scenarios. The first approach, called the Green's Function. In slab geometry, the Green's function is incorporated into a set of integral equations for the boundary fluxes. Through a numerical Fourier transform inversion and subsequent matrix inversion for the boundary fluxes, a semi-analytical benchmark emerges. Multidimensional solutions in a variety of infinite media are also based on the slab Green's function. In a second approach, a new converged SN method is developed. In this method, the SN solution is ''minded'' to bring out hidden high quality solutions. For this case multigroup fixed source and criticality transport problems are considered. Remarkably accurate solutions can be obtained with this new method called the Multigroup Converged SN (MGCSN) method as will be demonstrated.

B.D. Ganapol

2005-01-19

324

Pipe weld crown removal device  

DOEpatents

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.

Sword, Charles K. (Pleasant Hills, PA); Sette, Primo J. (West Newton, PA)

1992-01-01

325

Heat pipe turbine vane cooling  

SciTech Connect

The applicability of using heat pipe principles to cool gas turbine vanes is addressed in this beginning program. This innovative concept involves fitting out the vane interior as a heat pipe and extending the vane into an adjacent heat sink, thus transferring the vane incident heat transfer through the heat pipe to heat sink. This design provides an extremely high heat transfer rate and a uniform temperature along the vane due to the internal change of phase of the heat pipe working fluid. Furthermore, this technology can also eliminate hot spots at the vane leading and trailing edges and increase the vane life by preventing thermal fatigue cracking. There is also the possibility of requiring no bleed air from the compressor, and therefore eliminating engine performance losses resulting from the diversion of compressor discharge air. Significant improvement in gas turbine performance can be achieved by using heat pipe technology in place of conventional air cooled vanes. A detailed numerical analysis of a heat pipe vane will be made and an experimental model will be designed in the first year of this new program.

Langston, L.; Faghri, A. [Connecticut Univ., Storrs, CT (United States). Dept. of Mechanical Engineering

1995-12-31

326

Light Pipe Energy Savings Calculator  

NASA Astrophysics Data System (ADS)

Dependence on fossil fuels is unsustainable and therefore a shift to renewable energy sources such as sunlight is required. Light pipes provide a way to utilize sunlight for interior lighting, and can reduce the need for fossil fuel-generated electrical energy. Because consumers considering light pipe installation may be more strongly motivated by cost considerations than by sustainability arguments, an easy means to examine the corresponding costs and benefits is needed to facilitate informed decision-making. The purpose of this American Physical Society Physics and Society Fellowship project is to create a Web-based calculator to allow users to quantify the possible cost savings for their specific light pipe application. Initial calculations show that the illumination provided by light pipes can replace electric light use during the day, and in many cases can supply greater illumination levels than those typically given by electric lighting. While the installation cost of a light pipe is significantly greater than the avoided cost of electricity over the lifetime of the light pipe at current prices, savings may be realized if electricity prices increase.

Owens, Erin; Behringer, Ernest R.

2009-04-01

327

Heat pipe cooled power magnetics  

NASA Technical Reports Server (NTRS)

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.

Chester, M. S.

1979-01-01

328

Automated internal pipe cutting device  

DOEpatents

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.

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

329

The dynamics of axisymmetric swirling flows in a diverging or contracting circular pipe  

NASA Astrophysics Data System (ADS)

This paper describes a study of the effect of pipe divergence and contraction on the stability and breakdown of axisymmetric swirling flows in a long, finite-length, circular pipe. The work extends the theory of Wang & Rusak (1997). The approach is based on a rigorous analysis of the axisymmetric, steady and inviscid flow equations with non-periodic boundary conditions. The analysis firmly establishes the global bifurcation of flow states in the pipe (solutions of the Squire-Long PDE) by relating it to the bifurcation of solutions of the columnar flow problem (solutions of the resulting ODE) and using a new flow force relationship between the inlet and outlet states. This technique provides a simple, yet exact, method of analyzing the complex flow behavior including transitions from near-columnar vortex states to flow fields with large separation (stagnation) zones along the pipe centerline (breakdown states) or along the pipe wall (swirl induced wall separation). Bifurcation diagrams for base vortex models including the solid- body rotation and the Burgers vortex are presented. The stability characteristics of the various branches of solutions and the flow dynamics in the pipe under various perturbations are discussed. Results show that pipe divergence or contraction significantly modify the global flow behavior in a straight pipe and shed light on the effect of pipe geometry on the mechanism of vortex breakdown.

Rusak, Zvi; Wang, Shixiao

2009-11-01

330

Development of high performance sintered powder metal wick cryogenic heat pipes  

NASA Astrophysics Data System (ADS)

This paper presents recent development efforts at Eastman Kodak and Thermacore in the area of design, analysis, and testing of cryogenic heat pipes. Two nitrogen heat pipes designed to operate near 80K were designed, built and tested. The first heat pipe was 0.96 meters long and used a sintered homogeneous powder wick that demonstrated a heat transport capability of 3.5 watts at approximately 80K. The second heat pipe was 0.95 meters long with a sintered artery wick that demonstrated a capability of 20 to 25 watts at 0.004 m against gravity at 95K. The cryogenic arterial heat pipe represents an advance in heat pipe technology; twenty-fold improvement in performance is possible compared to a sintered homogeneous powder metal wick. The improvement results from use of a boiling-resistant artery design employing sintered wick technology. Also presented are support equipment requirements and special problems associated with the testing of cryogenic heat pipes. Some of the unique aspects of cryogenic heat pipes include initial start-up and priming of the system, control of system heat leaks, and determining optimum fluid charge for the heat pipe.

Compagna, G. L.; Rosenfeld, J. H.

1988-06-01

331

Toxicological benchmarks for synfuels characterization  

SciTech Connect

High-boiling petroleum distillates are quite different from crude coal liquids of similar boiling range and more likel hydrotreated coal liquids in their content of PAH dermal tumorigens, tumorigenicity, and mutagenicity. Refining levels our differences in the composition among the crude oils, and lesser compositional differences are observed for their refined naphthas. Differences (if any) in the toxicity of the vapors of the naphthas are likely to be small and subtle. More complex and comprehensive biological testing would be required to quantitate differences in potential health effects. However, the results suggest that the HFO/HD and VGO distillates of these petroleum crude oils are not substantially more mutagenic or tumorigenic than the undistilled petroleum crude oils, in comparison to crude coal liquids. Thus, there do not appear to be any substantial advantages to preparing and using distillate fractions (at least of these) petroleum crude oils as benchmarks for comparative mutagenicity and tumorigenicity testing. The original data in the literature on unfractionated petroleum crude oils appear suitable for comparison with coal liquids. The concentrations of selected four- to six-ring PAH dermal tumorigens in the high boiling distillate fractions of lighter petroleum crude oils were found to be only ca. 2.5 times more concentrated than in the undistilled crude oils. Further, these PAH in the distillate fractions were at least one to two orders of magnitude lower than in crude coal liquids of comparable boiling range, and more similar to those of hydrotreated coal liquids. 26 refs., 2 figs., 12 tabs.

Griest, W.H.; Tomkins, B.A.; Smith, L.H.; Buchanan, M.V.; Higgins, C.E.; Epler, J.L.; Witschi, H.R.

1986-08-01

332

Metrics and Benchmarks for Visualization  

NASA Technical Reports Server (NTRS)

What is a "good" visualization? How can the quality of a visualization be measured? How can one tell whether one visualization is "better" than another? I claim that the true quality of a visualization can only be measured in the context of a particular purpose. The same image generated from the same data may be excellent for one purpose and abysmal for another. A good measure of visualization quality will correspond to the performance of users in accomplishing the intended purpose, so the "gold standard" is user testing. As a user of visualization software (or at least a consultant to such users) I don't expect visualization software to have been tested in this way for every possible use. In fact, scientific visualization (as distinct from more "production oriented" uses of visualization) will continually encounter new data, new questions and new purposes; user testing can never keep up. User need software they can trust, and advice on appropriate visualizations of particular purposes. Considering the following four processes, and their impact on visualization trustworthiness, reveals important work needed to create worthwhile metrics and benchmarks for visualization. These four processes are (1) complete system testing (user-in-loop), (2) software testing, (3) software design and (4) information dissemination. Additional information is contained in the original extended abstract.

Uselton, Samuel P.; Lasinski, T. A. (Technical Monitor)

1995-01-01

333

Benchmarking Sustainability: the use of Indicators  

E-print Network

Benchmarking Sustainability: the use of Indicators Introduction The concept of sustainable development is both very popular and elusive. The overwhelming appeal of sustainability is situated to build a generally shared perception of sustainable development (Butler, 1998). For many people

Zaferatos, Nicholas C.

334

Toward Scalable Benchmarks for Mass Storage Systems  

NASA Technical Reports Server (NTRS)

This paper presents guidelines for the design of a mass storage system benchmark suite, along with preliminary suggestions for programs to be included. The benchmarks will measure both peak and sustained performance of the system as well as predicting both short- and long-term behavior. These benchmarks should be both portable and scalable so they may be used on storage systems from tens of gigabytes to petabytes or more. By developing a standard set of benchmarks that reflect real user workload, we hope to encourage system designers and users to publish performance figures that can be compared with those of other systems. This will allow users to choose the system that best meets their needs and give designers a tool with which they can measure the performance effects of improvements to their systems.

Miller, Ethan L.

1996-01-01

335

The FLUKA code: description and benchmarking  

SciTech Connect

The physics model implemented inside the FLUKA code are briefly described, with emphasis on hadronic interactions. Examples of the capabilities of the code are presented including basic (thin target) and complex benchmarks.

Battistoni, G.; Muraro, S.; Sala, P. R. [INFN sezione di Milano, via Celoria 16, I-20133 Milan (Italy); Cerutti, F.; Ferrari, A.; Roesler, S. [CERN, CH-1211 GENEVE 23 (Switzerland); Fasso, A. [SLAC, Stanford (United States); Ranft, J. [Siegen University (Germany)

2007-03-19

336

The FLUKA Code: Description And Benchmarking  

SciTech Connect

The physics model implemented inside the FLUKA code are briefly described, with emphasis on hadronic interactions. Examples of the capabilities of the code are presented including basic (thin target) and complex benchmarks.

Battistoni, Giuseppe; Muraro, S.; Sala, Paola R.; /INFN, Milan; Cerutti, Fabio; Ferrari, A.; Roesler, Stefan; /CERN; Fasso, A.; /SLAC; Ranft, J.; /Siegen U.

2007-09-18

337

Calculation of natural and forced vibrations of a piping system. Part 2. Dynamic stiffness of a pipe bend  

Microsoft Academic Search

The notion of the dynamic flexibility factor of a pipe bend to be used in problems on the calculation of harmonic vibrations\\u000a of pipelines is formulated. Based on the Vlasov semi-momentless theory, simplifying hypotheses are introduced that make it\\u000a possible to reduce the problem statement to the solution of the quartic differential equation. Using the results of the dynamic\\u000a analysis

I. V. Orynyak; S. A. Radchenko; A. S. Batura

2007-01-01

338

Turbulent-Laminar Patterns in Pipes and Channels  

NASA Astrophysics Data System (ADS)

When fluid flows through a channel, pipe, or duct, there are two basic forms of motion: smooth laminar motion and complex turbulent motion. The discontinuous transition between these states is a fundamental problem that has been studied for more than 100 years. What has received far less attention is the large-scale nature of the turbulent flows near transition once they are established. We have carried out extensive numerical computations in pipes and channels to investigate the nature of transitional turbulence in these flow. We show the existence of three fundamentally different turbulent states separated by two distinct Reynolds numbers. In the case of pipe flow for example, below Re approximately 2200, turbulence takes the form of familiar equilibrium (or long-time transient) puffs. The turbulence is intensive -- puffs are localized and the ratio of turbulent to laminar flow is not dictated by system size but by factors such as initial conditions. At Re=2200 the flow makes a striking transition to extensive turbulence where the amount of turbulent flow scales with pipe length. The asymptotic state is an irregular (intermittent) alternation of turbulent and laminar flow whose complexity is inherent and does not result from random initial disturbances. Intermittency continues until Re=2500 where the intermittency factor, and other measures, reveal a continuous transition to a state of uniform turbulence along the pipe. We argue that these states are a manifestation of universal large-scale structures in transitional shear flows.

Barkley, Dwight

2010-03-01

339

Implementation of NAS Parallel Benchmarks in Java  

NASA Technical Reports Server (NTRS)

A number of features make Java an attractive but a debatable choice for High Performance Computing (HPC). In order to gauge the applicability of Java to the Computational Fluid Dynamics (CFD) we have implemented NAS Parallel Benchmarks in Java. The performance and scalability of the benchmarks point out the areas where improvement in Java compiler technology and in Java thread implementation would move Java closer to Fortran in the competition for CFD applications.

Frumkin, Michael; Schultz, Matthew; Jin, Hao-Qiang; Yan, Jerry

2000-01-01

340

A framework for benchmarking land models  

SciTech Connect

Land models, which have been developed by the modeling community in the past few decades to predict future states of ecosystems and climate, have to be critically evaluated for their performance skills of simulating ecosystem responses and feedback to climate change. Benchmarking is an emerging procedure to measure performance of models against a set of defined standards. This paper proposes a benchmarking framework for evaluation of land model performances and, meanwhile, highlights major challenges at this infant stage of benchmark analysis. The framework includes (1) targeted aspects of model performance to be evaluated, (2) a set of benchmarks as defined references to test model performance, (3) metrics to measure and compare performance skills among models so as to identify model strengths and deficiencies, and (4) model improvement. Land models are required to simulate exchange of water, energy, carbon and sometimes other trace gases between the atmosphere and land surface, and should be evaluated for their simulations of biophysical processes, biogeochemical cycles, and vegetation dynamics in response to climate change across broad temporal and spatial scales. Thus, one major challenge is to select and define a limited number of benchmarks to effectively evaluate land model performance. The second challenge is to develop metrics of measuring mismatches between models and benchmarks. The metrics may include (1) a priori thresholds of acceptable model performance and (2) a scoring system to combine datamodel mismatches for various processes at different temporal and spatial scales. The benchmark analyses should identify clues of weak model performance to guide future development, thus enabling improved predictions of future states of ecosystems and climate. The near-future research effort should be on development of a set of widely acceptable benchmarks that can be used to objectively, effectively, and reliably evaluate fundamental properties of land models to improve their prediction performance skills.

Luo, Yiqi; Randerson, J.; Abramowitz, G.; Bacour, C.; Blyth, E.; Carvalhais, N.; Ciais, Philippe; Dalmonech, D.; Fisher, J.B.; Fisher, R.; Friedlingstein, P.; Hibbard, Kathleen A.; Hoffman, F. M.; Huntzinger, Deborah; Jones, C.; Koven, C.; Lawrence, David M.; Li, D.J.; Mahecha, M.; Niu, S.L.; Norby, Richard J.; Piao, S.L.; Qi, X.; Peylin, P.; Prentice, I.C.; Riley, William; Reichstein, M.; Schwalm, C.; Wang, Y.; Xia, J. Y.; Zaehle, S.; Zhou, X. H.

2012-10-09

341

A framework for benchmarking land models  

SciTech Connect

Land models, which have been developed by the modeling community in the past few decades to predict future states of ecosystems and climate, have to be critically evaluated for their performance skills of simulating ecosystem responses and feedback to climate change. Benchmarking is an emerging procedure to measure performance of models against a set of defined standards. This paper proposes a benchmarking framework for evaluation of land model performances and, meanwhile, highlights major challenges at this infant stage of benchmark analysis. The framework includes (1) targeted aspects of model performance to be evaluated, (2) a set of benchmarks as defined references to test model performance, (3) metrics to measure and compare performance skills among models so as to identify model strengths and deficiencies, and (4) model improvement. Land models are required to simulate exchange of water, energy, carbon and sometimes other trace gases between the atmosphere and land surface, and should be evaluated for their simulations of biophysical processes, biogeochemical cycles, and vegetation dynamics in response to climate change across broad temporal and spatial scales. Thus, one major challenge is to select and define a limited number of benchmarks to effectively evaluate land model performance. The second challenge is to develop metrics of measuring mismatches between models and benchmarks. The metrics may include (1) a priori thresholds of acceptable model performance and (2) a scoring system to combine data model mismatches for various processes at different temporal and spatial scales. The benchmark analyses should identify clues of weak model performance to guide future development, thus enabling improved predictions of future states of ecosystems and climate. The near-future research effort should be on development of a set of widely acceptable benchmarks that can be used to objectively, effectively, and reliably evaluate fundamental properties of land models to improve their prediction performance skills.

Luo, Yiqi [University of Oklahoma; Randerson, James T. [University of California, Irvine; Hoffman, Forrest [ORNL; Norby, Richard J [ORNL

2012-01-01

342

Simple Benchmark Specifications for Space Radiation Protection  

NASA Technical Reports Server (NTRS)

This report defines space radiation benchmark specifications. This specification starts with simple, monoenergetic, mono-directional particles on slabs and progresses to human models in spacecraft. This report specifies the models and sources needed to what the team performing the benchmark needs to produce in a report. Also included are brief descriptions of how OLTARIS, the NASA Langley website for space radiation analysis, performs its analysis.

Singleterry, Robert C. Jr.; Aghara, Sukesh K.

2013-01-01

343

A synergistic performance management model conjoining benchmarking and motivation  

Microsoft Academic Search

Purpose The purpose of this paper is to develop an improved management\\/performance model that yields superior business productivity by conjoining internal benchmarking, external benchmarking, and a strong employee performance\\/behavior paradigm. Design\\/methodology\\/approach Strengths and weaknesses of conventional benchmarking approaches to productivity maximization are examined through both literature surveys and experiments. Findings It is found that most benchmarking efforts

Anatoliy G. Goncharuk; Jamie P. Monat

2009-01-01

344

Process benchmarking as a market research tool for strategic planning  

Microsoft Academic Search

Process benchmarking partnerships are emerging as a research tool to help small firms to build a competitive advantage against larger rivals. Managers are now beginning to appreciate the need to benchmark the strategically relevant processes in their value chain. Process benchmarking begins with exploratory qualitative research to determine the core processes to be benchmarked. Quantitative research then follows, using an

Deborah Ralston; April Wright; Jaynendra Kumar

2001-01-01

345

Towards realistic file-system benchmarks with CodeMRI  

Microsoft Academic Search

Benchmarks are crucial to understanding software systems and assessing their performance. In file-system research, synthetic benchmarks are accepted and widely used as substitutes for more realistic and complex workloads. However, synthetic benchmarks are largely based on the benchmark writer's interpretation of the real workload, and how it exercises the system API. This is insufficient since even a simple operation through

Nitin Agrawal; Andrea C. Arpaci-Dusseau; Remzi H. Arpaci-Dusseau

2008-01-01

346

Machine characterization and benchmark performance prediction  

NASA Technical Reports Server (NTRS)

From runs of standard benchmarks or benchmark suites, it is not possible to characterize the machine nor to predict the run time of other benchmarks which have not been run. A new approach to benchmarking and machine characterization is reported. The creation and use of a machine analyzer is described, which measures the performance of a given machine on FORTRAN source language constructs. The machine analyzer yields a set of parameters which characterize the machine and spotlight its strong and weak points. Also described is a program analyzer, which analyzes FORTRAN programs and determines the frequency of execution of each of the same set of source language operations. It is then shown that by combining a machine characterization and a program characterization, we are able to predict with good accuracy the run time of a given benchmark on a given machine. Characterizations are provided for the Cray-X-MP/48, Cyber 205, IBM 3090/200, Amdahl 5840, Convex C-1, VAX 8600, VAX 11/785, VAX 11/780, SUN 3/50, and IBM RT-PC/125, and for the following benchmark programs or suites: Los Alamos (BMK8A1), Baskett, Linpack, Livermore Loops, Madelbrot Set, NAS Kernels, Shell Sort, Smith, Whetstone and Sieve of Erathostenes.

Saavedra-Barrera, Rafael H.

1988-01-01

347

Benchmarking initiatives in the water industry.  

PubMed

Customer satisfaction and service care are every day pushing professionals in the water industry to seek to improve their performance, lowering costs and increasing the provided service level. Process Benchmarking is generally recognised as a systematic mechanism of comparing one's own utility with other utilities or businesses with the intent of self-improvement by adopting structures or methods used elsewhere. The IWA Task Force on Benchmarking, operating inside the Statistics and Economics Committee, has been committed to developing a general accepted concept of Process Benchmarking to support water decision-makers in addressing issues of efficiency. In a first step the Task Force disseminated among the Committee members a questionnaire focused on providing suggestions about the kind, the evolution degree and the main concepts of Benchmarking adopted in the represented Countries. A comparison among the guidelines adopted in The Netherlands and Scandinavia has recently challenged the Task Force in drafting a methodology for a worldwide process benchmarking in water industry. The paper provides a framework of the most interesting benchmarking experiences in the water sector and describes in detail both the final results of the survey and the methodology focused on identification of possible improvement areas. PMID:11547972

Parena, R; Smeets, E

2001-01-01

348

Pool critical assembly pressure vessel facility benchmark  

SciTech Connect

This pool critical assembly (PCA) pressure vessel wall facility benchmark (PCA benchmark) is described and analyzed in this report. Analysis of the PCA benchmark can be used for partial fulfillment of the requirements for the qualification of the methodology for pressure vessel neutron fluence calculations, as required by the US Nuclear Regulatory Commission regulatory guide DG-1053. Section 1 of this report describes the PCA benchmark and provides all data necessary for the benchmark analysis. The measured quantities, to be compared with the calculated values, are the equivalent fission fluxes. In Section 2 the analysis of the PCA benchmark is described. Calculations with the computer code DORT, based on the discrete-ordinates method, were performed for three ENDF/B-VI-based multigroup libraries: BUGLE-93, SAILOR-95, and BUGLE-96. An excellent agreement of the calculated (C) and measures (M) equivalent fission fluxes was obtained. The arithmetic average C/M for all the dosimeters (total of 31) was 0.93 {+-} 0.03 and 0.92 {+-} 0.03 for the SAILOR-95 and BUGLE-96 libraries, respectively. The average C/M ratio, obtained with the BUGLE-93 library, for the 28 measurements was 0.93 {+-} 0.03 (the neptunium measurements in the water and air regions were overpredicted and excluded from the average). No systematic decrease in the C/M ratios with increasing distance from the core was observed for any of the libraries used.

Remec, I.; Kam, F.B.K. [Oak Ridge National Lab., TN (United States)

1997-07-01

349

Benchmarking infrastructure for mutation text mining  

PubMed Central

Background Experimental research on the automatic extraction of information about mutations from texts is greatly hindered by the lack of consensus evaluation infrastructure for the testing and benchmarking of mutation text mining systems. Results We propose a community-oriented annotation and benchmarking infrastructure to support development, testing, benchmarking, and comparison of mutation text mining systems. The design is based on semantic standards, where RDF is used to represent annotations, an OWL ontology provides an extensible schema for the data and SPARQL is used to compute various performance metrics, so that in many cases no programming is needed to analyze results from a text mining system. While large benchmark corpora for biological entity and relation extraction are focused mostly on genes, proteins, diseases, and species, our benchmarking infrastructure fills the gap for mutation information. The core infrastructure comprises (1) an ontology for modelling annotations, (2) SPARQL queries for computing performance metrics, and (3) a sizeable collection of manually curated documents, that can support mutation grounding and mutation impact extraction experiments. Conclusion We have developed the principal infrastructure for the benchmarking of mutation text mining tasks. The use of RDF and OWL as the representation for corpora ensures extensibility. The infrastructure is suitable for out-of-the-box use in several important scenarios and is ready, in its current state, for initial community adoption. PMID:24568600

2014-01-01

350

Quality measures for protein alignment benchmarks.  

PubMed

Multiple protein sequence alignment methods are central to many applications in molecular biology. These methods are typically assessed on benchmark datasets including BALIBASE, OXBENCH, PREFAB and SABMARK, which are important to biologists in making informed choices between programs. In this article, annotations of domain homology and secondary structure are used to define new measures of alignment quality and are used to make the first systematic, independent evaluation of these benchmarks. These measures indicate sensitivity and specificity while avoiding the ambiguous residue correspondences and arbitrary distance cutoffs inherent to structural superpositions. Alignments by selected methods that indicate high-confidence columns (ALIGN-M, DIALIGN-T, FSA and MUSCLE) are also assessed. Fold space coverage and effective benchmark database sizes are estimated by reference to domain annotations, and significant redundancy is found in all benchmarks except SABMARK. Questionable alignments are found in all benchmarks, especially in BALIBASE where 87% of sequences have unknown structure, 20% of columns contain different folds according to SUPERFAMILY and 30% of 'core block' columns have conflicting secondary structure according to DSSP. A careful analysis of current protein multiple alignment benchmarks calls into question their ability to determine reliable algorithm rankings. PMID:20047958

Edgar, Robert C

2010-04-01

351

The skyshine benchmark experiment revisited.  

PubMed

With the coming renaissance of nuclear power, heralded by new nuclear power plant construction in Finland, the issue of qualifying modern tools for calculation becomes prominent. Among the calculations required may be the determination of radiation levels outside the plant owing to skyshine. For example, knowledge of the degree of accuracy in the calculation of gamma skyshine through the turbine hall roof of a BWR plant is important. Modern survey programs which can calculate skyshine dose rates tend to be qualified only by verification with the results of Monte Carlo calculations. However, in the past, exacting experimental work has been performed in the field for gamma skyshine, notably the benchmark work in 1981 by Shultis and co-workers, which considered not just the open source case but also the effects of placing a concrete roof above the source enclosure. The latter case is a better reflection of reality as safety considerations nearly always require the source to be shielded in some way, usually by substantial walls but by a thinner roof. One of the tools developed since that time, which can both calculate skyshine radiation and accurately model the geometrical set-up of an experiment, is the code RANKERN, which is used by Framatome ANP and other organisations for general shielding design work. The following description concerns the use of this code to re-address the experimental results from 1981. This then provides a realistic gauge to validate, but also to set limits on, the program for future gamma skyshine applications within the applicable licensing procedures for all users of the code. PMID:16604694

Terry, Ian R

2005-01-01

352

Magnetic refrigeration apparatus with heat pipes  

DOEpatents

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.

Barclay, J.A.; Prenger, F.C. Jr.

1985-10-25

353

Magnetic refrigeration apparatus with heat pipes  

DOEpatents

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.

Barclay, John A. (Los Alamos, NM); Prenger, Jr., F. Coyne (Madison, WI)

1987-01-01

354

Centrally activated pipe snubbing system  

DOEpatents

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.

Cawley, William E. (Richland, WA)

1985-01-01

355

Pipe crawler with extendable legs  

DOEpatents

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.

Zollinger, William T. (3927 Almon Dr., Martinez, GA 30907)

1992-01-01

356

Pipe crawler with extendable legs  

DOEpatents

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.

Zollinger, W.T.

1992-06-16

357

Flexible ultrasonic pipe inspection apparatus  

DOEpatents

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.

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

1998-06-23

358

Holographic NDT methods for plastic pipe vibration and brittle crack propagation analysis  

NASA Astrophysics Data System (ADS)

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.

Markov, Vladimir B.; Boone, Pierre M.; Vanspeybroeck, Philippe

1995-11-01

359

Benchmarking the QUAD4/TRIA3 element  

NASA Technical Reports Server (NTRS)

The QUAD4 and TRIA3 elements are the primary plate/shell elements in NASTRAN. These elements enable the user to analyze thin plate/shell structures for membrane, bending and shear phenomena. They are also very new elements in the NASTRAN library. These elements are extremely versatile and constitute a substantially enhanced analysis capability in NASTRAN. However, with the versatility comes the burden of understanding a myriad of modeling implications and their effect on accuracy and analysis quality. The validity of many aspects of these elements were established through a series of benchmark problem results and comparison with those available in the literature and obtained from other programs like MSC/NASTRAN and CSAR/NASTRAN. Never-the-less such a comparison is never complete because of the new and creative use of these elements in complex modeling situations. One of the important features of QUAD4 and TRIA3 elements is the offset capability which allows the midsurface of the plate to be noncoincident with the surface of the grid points. None of the previous elements, with the exception of bar (beam), has this capability. The offset capability played a crucial role in the design of QUAD4 and TRIA3 elements. It allowed modeling layered composites, laminated plates and sandwich plates with the metal and composite face sheets. Even though the basic implementation of the offset capability is found to be sound in the previous applications, there is some uncertainty in relatively simple applications. The main purpose of this paper is to test the integrity of the offset capability and provide guidelines for its effective use. For the purpose of simplicity, references in this paper to the QUAD4 element will also include the TRIA3 element.

Pitrof, Stephen M.; Venkayya, Vipperla B.

1993-01-01

360

A Comparison of Monte Carlo Particle Transport Algorithms for an Interior Source Binary Stochastic Medium Benchmark Suite  

SciTech Connect

Particle transport through binary stochastic mixtures has received considerable research attention in the last two decades. Zimmerman and Adams proposed a Monte Carlo algorithm (Algorithm A) that solves the Levermore-Pomraning equations and another Monte Carlo algorithm (Algorithm B) that should be more accurate as a result of improved local material realization modeling. Zimmerman and Adams numerically confirmed these aspects of the Monte Carlo algorithms by comparing the reflection and transmission values computed using these algorithms to a standard suite of planar geometry binary stochastic mixture benchmark transport solutions. The benchmark transport problems are driven by an isotropic angular flux incident on one boundary of a binary Markovian statistical planar geometry medium. In a recent paper, we extended the benchmark comparisons of these Monte Carlo algorithms to include the scalar flux distributions produced. This comparison is important, because as demonstrated, an approximate model that gives accurate reflection and transmission probabilities can produce unphysical scalar flux distributions. Brantley and Palmer recently investigated the accuracy of the Levermore-Pomraning model using a new interior source binary stochastic medium benchmark problem suite. In this paper, we further investigate the accuracy of the Monte Carlo algorithms proposed by Zimmerman and Adams by comparing to the benchmark results from the interior source binary stochastic medium benchmark suite, including scalar flux distributions. Because the interior source scalar flux distributions are of an inherently different character than the distributions obtained for the incident angular flux benchmark problems, the present benchmark comparison extends the domain of problems for which the accuracy of these Monte Carlo algorithms has been investigated.

Brantley, P S

2009-06-30

361

Properties of Yeditepe Examination Timetabling Benchmark Andrew J. Parkes Ender Ozcan  

E-print Network

PATAT 2010 Properties of Yeditepe Examination Timetabling Benchmark Instances Andrew J. Parkes · Ender ¨Ozcan May 2010 1 Introduction Examination timetabling is a type of educational timetabling which is a highly challeng- ing field for the researchers and practitioners. Examination timetabling problems

Parkes, Andrew J.

362

Design and Implementation of the HPCS Graph Analysis Benchmark on Symmetric Multiprocessors  

Microsoft Academic Search

Graph theoretic problems are representative of fundamental computations in tra- ditional and emerging scientific disciplines like scientific computing, computational biology and bioinformatics, as well as applications in national security. We present our design and implementation of a graph theory application that supports the kernels from the Scalable Synthetic Compact Applications (SSCA) benchmark suite, devel- oped under the DARPA High Productivity

David A. Baderand; Kamesh Madduri

2005-01-01

363

On Establishing a Benchmark for Evaluating Static Analysis Alert Prioritization and Classification Techniques  

E-print Network

On Establishing a Benchmark for Evaluating Static Analysis Alert Prioritization and Classification of techniques that prioritize and classify alerts generated by static analysis tools. Alert prioritization and classification addresses the problem in many static analysis tools of numerous alerts that are not an indication

Young, R. Michael

364

A NEW BENCHMARK QUALITY SOLUTION FOR THE BUOYANCY-DRIVEN CAVITY  

E-print Network

A NEW BENCHMARK QUALITY SOLUTION FOR THE BUOYANCY-DRIVEN CAVITY BY DISCRETE SINGULAR CONVOLUTION D simple geo- metries, such as the buoyancy-driven square cavity, is a necessary precursor to the evolution of better designs for more complex industrial applications. Jones [1] has proposed the problem of a buoyancy

Wei, Guo-Wei

365

46 CFR 153.292 - Separation of piping systems.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Separation of piping systems. 153.292 Section 153...Design and Equipment Piping Systems and Cargo Handling Equipment 153.292 Separation of piping systems. Cargo piping systems...

2010-10-01

366

46 CFR 153.292 - Separation of piping systems.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Separation of piping systems. 153.292 Section 153...Design and Equipment Piping Systems and Cargo Handling Equipment 153.292 Separation of piping systems. Cargo piping systems...

2011-10-01

367

46 CFR 154.512 - Piping: Thermal isolation.  

Code of Federal Regulations, 2010 CFR

...Shipping 5 2010-10-01 2010-10-01 false Piping: Thermal isolation. 154.512 Section 154.512 Shipping ...Cargo and Process Piping Systems 154.512 Piping: Thermal isolation. Low temperature piping must be thermally...

2010-10-01

368

Multiple heat pipe heat exchanger and method for making  

Microsoft Academic Search

A heat pipe heat exchanger has a plurality of heat pipes which are interconnected so as to permit fluid communication between the pipes at least during charging so that the heat pipes may be simultaneously filled with heat transfer fluid.

Maxson

1979-01-01

369

Cryogenic thermal diode heat pipes  

NASA Technical Reports Server (NTRS)

The development of spiral artery cryogenic thermal diode heat pipes was continued. Ethane was the working fluid and stainless steel the heat pipe material in all cases. The major tasks included: (1) building a liquid blockage (blocking orifice) thermal diode suitable for the HEPP space flight experiment; (2) building a liquid trap thermal diode engineering model; (3) retesting the original liquid blockage engineering model, and (4) investigating the startup dynamics of artery cryogenic thermal diodes. An experimental investigation was also conducted into the wetting characteristics of ethane/stainless steel systems using a specially constructed chamber that permitted in situ observations.

Alario, J.

1979-01-01

370

Action-Oriented Benchmarking: Using the CEUS Database to Benchmark Commercial Buildings in California  

SciTech Connect

The 2006 Commercial End Use Survey (CEUS) database developed by the California Energy Commission is a far richer source of energy end-use data for non-residential buildings than has previously been available and opens the possibility of creating new and more powerful energy benchmarking processes and tools. In this article--Part 2 of a two-part series--we describe the methodology and selected results from an action-oriented benchmarking approach using the new CEUS database. This approach goes beyond whole-building energy benchmarking to more advanced end-use and component-level benchmarking that enables users to identify and prioritize specific energy efficiency opportunities - an improvement on benchmarking tools typically in use today.

Mathew, Paul; Mills, Evan; Bourassa, Norman; Brook, Martha

2008-02-01

371

46 CFR 154.660 - Pipe welding.  

Code of Federal Regulations, 2011 CFR

...of this chapter. (b) Longitudinal butt welds, in piping that does not meet a standard or...56.60-1 of this chapter, and girth butt welds must meet the following: (1) Butt welds of pipes made from carbon, carbon...

2011-10-01

372

46 CFR 154.660 - Pipe welding.  

Code of Federal Regulations, 2012 CFR

...of this chapter. (b) Longitudinal butt welds, in piping that does not meet a standard or...56.60-1 of this chapter, and girth butt welds must meet the following: (1) Butt welds of pipes made from carbon, carbon...

2012-10-01

373

46 CFR 154.660 - Pipe welding.  

Code of Federal Regulations, 2013 CFR

...of this chapter. (b) Longitudinal butt welds, in piping that does not meet a standard or...56.60-1 of this chapter, and girth butt welds must meet the following: (1) Butt welds of pipes made from carbon, carbon...

2013-10-01

374

46 CFR 154.660 - Pipe welding.  

Code of Federal Regulations, 2010 CFR

...of this chapter. (b) Longitudinal butt welds, in piping that does not meet a standard or...56.60-1 of this chapter, and girth butt welds must meet the following: (1) Butt welds of pipes made from carbon, carbon...

2010-10-01

375

14 CFR 29.1123 - Exhaust piping.  

...CATEGORY ROTORCRAFT Powerplant Exhaust System 29.1123 Exhaust piping. (a) Exhaust piping must be heat and corrosion resistant, and must have provisions to prevent failure due to expansion by operating temperatures. (b) Exhaust...

2014-01-01

376

14 CFR 25.1123 - Exhaust piping.  

Code of Federal Regulations, 2011 CFR

...power unit installations, the following apply: (a) Exhaust piping must be heat and corrosion resistant, and must have provisions to prevent failure due to expansion by operating temperatures. (b) Piping must be supported to...

2011-01-01

377

14 CFR 25.1123 - Exhaust piping.  

Code of Federal Regulations, 2010 CFR

...power unit installations, the following apply: (a) Exhaust piping must be heat and corrosion resistant, and must have provisions to prevent failure due to expansion by operating temperatures. (b) Piping must be supported to...

2010-01-01

378

Flat heat pipe design, construction, and analysis  

SciTech Connect

This paper details the design, construction and partial analysis of a low temperature flat heat pipe in order to determine the feasibility of implementing flat heat pipes into thermophotovoltaic (TPV) energy conversion systems.

Voegler, G.; Boughey, B.; Cerza, M.; Lindler, K.W.

1999-08-02

379

46 CFR 108.475 - Piping.  

Code of Federal Regulations, 2011 CFR

...and outside from corrosion. (c) Each pipe, valve, and fitting must have support and...extinguishing system must have enough (1) Dirt traps to prevent the accumulation of dirt in its pipes; and (2) Drains to remove liquid...

2011-10-01

380

46 CFR 108.475 - Piping.  

Code of Federal Regulations, 2010 CFR

...and outside from corrosion. (c) Each pipe, valve, and fitting must have support and...extinguishing system must have enough (1) Dirt traps to prevent the accumulation of dirt in its pipes; and (2) Drains to remove liquid...

2010-10-01

381

Heat pipe applications in aircraft propulsion  

NASA Technical Reports Server (NTRS)

Heat pipes for improving the cycle efficiency and/or thrust-to-weight ratio of aircraft gas turbines are examined. A heat pipe employs a capillary structure, a wick, and an evacuated chamber to transfer heat between condensor and evaporator ends. Heat absorbed at the evaporator is transported to the condensor. In an aircraft, the heat pipe can be stationary or rotating, can be used for cooling stators and rotors, and is amenable to shapes such as cylinders, cones, and flat plates. Heat pipes in aircraft gas turbines can be applied for intercooling between stages, regeneration, reheat, and blade cooling. Improvements are projected in the cycle efficiency, thrust and thrust specific fuel consumption in the fanjet by using heat pipes. Consideration is also given to heat pipe heat exchangers with high axial heat transfer for stationary heat pipes and high heat transport for rotating heat pipes.

Beltran, M. R.; Anderson, D. L.; Marto, P. J.

1984-01-01

382

Heat pipe design handbook, part 1  

NASA Technical Reports Server (NTRS)

The development and characteristics of heat pipes are examined. The subjects discussed are: (1) principles of operation, (2) heat pipe theory, (3) pressure gradient effects, (4) variable conductance, (5) design procedure, and (6) performance limit evaluation.

Skrabek, E. A.

1972-01-01

383

Experimental Measurement and Analysis of Performance of Heat Pipe Heat Exchanger Used in Turbocharged Engine with Intercooling  

Microsoft Academic Search

Turbo charging technology with higher compression ratio has been widely applied in engine and the strength losing of aluminum charge air cooler becomes a problem attracted increasing attention. Heat pipe charge air cooler (HPCAC) is a new type CAC, which can withstand high temperature. An experimental study of a gravity assisted HPCAC were performed. Several configurations of heat pipe heat

Weiguo Yan; Xiaoli Yu; Guodong Lu

2012-01-01

384

Experimental Measurement and Analysis of Performance of Heat Pipe Heat Exchanger Used in a Turbocharged Engine with Intercooling  

Microsoft Academic Search

Turbocharging technology with higher compression ratio has been widely applied in engines and the strength loss of an aluminum charge air cooler becomes a problem attracting increased attention. The heat pipe charge air cooler (HPCAC) is a new type of CAC that can withstand high temperature. An experimental study of a gravity-assisted HPCAC was performed. Several configurations of heat pipe

Weiguo Yan; Xiaoli Yu; Guodong Lu

2012-01-01

385

Mathematical Model of the Optimum Heat Pipe Heat Exchanger for a Condenser of Vapor-Compression Refrigeration Cycle  

Microsoft Academic Search

Problem statement: This study theoretically investigated applying heat pipe as a heat exchanger in the condenser of vapor compression refrigeration system for sustainable well-being. Split- type air conditioner for residential propose was co nsidered. To reduce pressure drop and recover heat from the condensing process of the refrigeration cy cle, this investigation tried to use Closed Loop Oscillating Heat Pipe

P. Yeunyongkul; P. Sakulchangsatjatai; P. Terdto

2010-01-01

386

Toxicological benchmarks for wildlife: 1994 Revision  

SciTech Connect

The process by which ecological risks of environmental contaminants are evaluated is two-tiered. The first tier is a screening assessment where concentrations of contaminants in the environment are compared to toxicological benchmarks which represent concentrations of chemicals in environmental media (water, sediment, soil, food, etc.) that are presumed to be nonhazardous to the surrounding biota. The second tier is a baseline ecological risk assessment where toxicological benchmarks are one of several lines of evidence used to support or refute the presence of ecological effects. The report presents toxicological benchmarks for assessment of effects of 76 chemicals on 8 representative mammalian wildlife species and 31 chemicals on 9 avian wildlife species. The chemicals are some of those that occur at United States Department of Energy waste sites; the wildlife species were chosen because they are widely distributed and provide a representative range of body sizes and diets. Further descriptions of the chosen wildlife species and chemicals are provided in the report. The benchmarks presented in this report represent values believed to be nonhazardous for the listed wildlife species. These benchmarks only consider contaminant exposure through oral ingestion of contaminated media; exposure through inhalation or direct dermal exposure are not considered in this report.

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

1994-09-01

387

Easy Problems are Sometimes Hard  

Microsoft Academic Search

We present a detailed experimental investigation of the easy-hard-easyphase transition for randomly generated instances of satisfiability problems.Problems in the hard part of the phase transition have been extensively usedfor benchmarking satisfiability algorithms. This study demonstrates thatproblem classes and regions of the phase transition previously thought tobe easy can sometimes be orders of magnitude more difficult than the worstproblems in problem

Ian P. Gent; Toby Walsh

1994-01-01

388

Dynamics of heat-pipe reactors  

NASA Technical Reports Server (NTRS)

A split-core heat pipe reactor, fueled with either U(233)C or U(235)C in a tungsten cermet and cooled by 7-Li-W heat pipes, was examined for the effects of the heat pipes on reactor while trying to safely absorb large reactivity inputs through inherent shutdown mechanisms. Limits on ramp reactivity inputs due to fuel melting temperature and heat pipe wall heat flux were mapped for the reactor in both startup and at-power operating modes.

Niederauer, G. F.

1971-01-01

389

Gray Cast-Iron Water Pipe Metallurgy  

Microsoft Academic Search

Abstract: The results of a,metallographic study of grey,cast iron water pipes are reported. These pipes had been installed between 1885 and 1973 in eight different water systems. Each pipe had been extracted during scheduled maintenance,or failure repairs to provide data for a larger study toproduce,a methodology ,for determining ,the residual life of grey ,cast iron pipes. This metallographic study was

J. M. Rajani

2000-01-01

390

Analysis of Municipal Pipe Network Franchise Institution  

NASA Astrophysics Data System (ADS)

Franchise institution of municipal pipe network has some particularity due to the characteristic of itself. According to the exposition of Chinese municipal pipe network industry franchise institution, the article investigates the necessity of implementing municipal pipe network franchise institution in China, the role of government in the process and so on. And this offers support for the successful implementation of municipal pipe network franchise institution in China.

Yong, Sun; Haichuan, Tian; Feng, Xu; Huixia, Zhou

391

A method for implementing a piping inspection  

SciTech Connect

Recent catastrophic piping failures dramatically demonstrate the importance of implementing a piping program. Piping system leaks and ruptures have caused death and injury to plant workers, firefighters, and the public. Significant financial consequences due to unexpected downtime and property damage have plagued industry. The environment has also suffered from the release of toxic chemicals. In the chemical industry, roughly 30% of the catastrophic losses have been historically attributable to piping failures. 1 fig. 1 tab.

Matthews, P.B. [Hartford Steam Boiler and Insurance Co., Hartford, CT (United States)] [Hartford Steam Boiler and Insurance Co., Hartford, CT (United States); Beberman, J.A. [Radian Corp., Tucker, GA (United States)] [Radian Corp., Tucker, GA (United States)

1995-01-01

392

The Challenge of Providing Safe Water with an Intermittently Supplied Piped Water Distribution System  

NASA Astrophysics Data System (ADS)

An increasing number of urban residents in low- and middle-income countries have access to piped water; however, this water is often not available continuously. 84% of reporting utilities in low-income countries provide piped water for fewer than 24 hours per day (van den Berg and Danilenko, 2010), while no major city in India has continuous piped water supply. Intermittent water supply leaves pipes vulnerable to contamination and forces households to store water or rely on alternative unsafe sources, posing a health threat to consumers. In these systems, pipes are empty for long periods of time and experience low or negative pressure even when water is being supplied, leaving them susceptible to intrusion from sewage, soil, or groundwater. Households with a non-continuous supply must collect and store water, presenting more opportunities for recontamination. Upgrading to a continuous water supply, while an obvious solution to these challenges, is currently out of reach for many resource-constrained utilities. Despite its widespread prevalence, there are few data on the mechanisms causing contamination in an intermittent supply and the frequency with which it occurs. Understanding the impact of intermittent operation on water quality can lead to strategies to improve access to safe piped water for the millions of people currently served by these systems. We collected over 100 hours of continuous measurements of pressure and physico-chemical water quality indicators and tested over 1,000 grab samples for indicator bacteria over 14 months throughout the distribution system in Hubli-Dharwad, India. This data set is used to explore and explain the mechanisms influencing water quality when piped water is provided for a few hours every 3-5 days. These data indicate that contamination occurs along the distribution system as water travels from the treatment plant to reservoirs and through intermittently supplied pipes to household storage containers, while real-time measurements document variability in water quality throughout the 2-8 hour supply period. Our results show that piped water is not always safe water, but that safe water can be achieved in an intermittent supply under certain physical and operational conditions. Intermittent piped water supply is an important constraint on access to safe water in towns and cities in low-income countries, and strategies that improve these existing systems can help urban residents gain access to safe water. References van den Berg, C., and Danilenko, A. (2010). "The IBNET Water Supply and Sanitation Performance Blue Book: The International Benchmarking Network for Water and Sanitation Utilities Databook." World Bank Washington, DC.

Kumpel, E.; Nelson, K. L.

2012-12-01

393

46 CFR 56.10-5 - Pipe.  

Code of Federal Regulations, 2012 CFR

...also 56.60-20.) (1) Copper and brass pipe for water and steam service may...temperatures to 406 F. (2) Copper and brass pipe for air may be used in accordance...pounds per square inch. (5) Copper, brass, or aluminum pipe or tube shall not...

2012-10-01

394

46 CFR 56.10-5 - Pipe.  

Code of Federal Regulations, 2013 CFR

...also 56.60-20.) (1) Copper and brass pipe for water and steam service may...temperatures to 406 F. (2) Copper and brass pipe for air may be used in accordance...pounds per square inch. (5) Copper, brass, or aluminum pipe or tube shall not...

2013-10-01

395

46 CFR 56.10-5 - Pipe.  

Code of Federal Regulations, 2011 CFR

...also 56.60-20.) (1) Copper and brass pipe for water and steam service may...temperatures to 406 F. (2) Copper and brass pipe for air may be used in accordance...pounds per square inch. (5) Copper, brass, or aluminum pipe or tube shall not...

2011-10-01

396

Bag Test Measures Leakage From Insulated Pipe  

NASA Technical Reports Server (NTRS)

Test quantifies leakage of gas from pipe even though pipe covered with insulation. Involves use of helium analyzer to measure concentration of helium in impermeable bag around pipe. Test administered after standard soap-solution bubble test indicates presence and general class of leakage.

Schock, Kent D.; Easter, Barry P.

1994-01-01

397

The locating ways of laying pipe manipulator  

NASA Astrophysics Data System (ADS)

The laying pipe manipulator is a new equipment to lay concrete pipe. This kind of manipulator makes the work of laying pipes mechanized and automated. We report here a new laying pipe manipulator. The manipulator has 5 free degrees, and is driven by the hydraulic system. In the paper, one critical question of manipulator is studied: the locating ways of the manipulator to lay concrete pipe. During the process of laying concrete pipe, how to locate the manipulator is realized by the locating system of manipulator. The locating system consists of photoelectric target, laser producer, and computer. According to different construction condition, one or two or three photoelectric targets can be used. During the process of laying concrete pipe, if the interface of pipes are jointed together, and the other segment of pipe deviates from the pipe way, one target can be used, if the angle that the manipulator rotates around the holding pipe's axes is 0, two targets can be used, three targets can be used at any site. In the paper, according to each locating way, the theory analysis is done. And the mathematical models of the manipulator moving from original position to goal position are obtained by different locating way. And the locating experiment was done. According to the experiment result, the work principle and mathematical models of different locating way was turned out to be well adopted for requirement, the mathematical model of different locating way supplies the basic control theory for the manipulator to lay and joint concrete pipe automatically.

Wang, Dan; Li, Bin; Lei, DongLiang

2010-01-01

398

The locating ways of laying pipe manipulator  

NASA Astrophysics Data System (ADS)

The laying pipe manipulator is a new equipment to lay concrete pipe. This kind of manipulator makes the work of laying pipes mechanized and automated. We report here a new laying pipe manipulator. The manipulator has 5 free degrees, and is driven by the hydraulic system. In the paper, one critical question of manipulator is studied: the locating ways of the manipulator to lay concrete pipe. During the process of laying concrete pipe, how to locate the manipulator is realized by the locating system of manipulator. The locating system consists of photoelectric target, laser producer, and computer. According to different construction condition, one or two or three photoelectric targets can be used. During the process of laying concrete pipe, if the interface of pipes are jointed together, and the other segment of pipe deviates from the pipe way, one target can be used, if the angle that the manipulator rotates around the holding pipe's axes is 0, two targets can be used, three targets can be used at any site. In the paper, according to each locating way, the theory analysis is done. And the mathematical models of the manipulator moving from original position to goal position are obtained by different locating way. And the locating experiment was done. According to the experiment result, the work principle and mathematical models of different locating way was turned out to be well adopted for requirement, the mathematical model of different locating way supplies the basic control theory for the manipulator to lay and joint concrete pipe automatically.

Wang, Dan; Li, Bin; Lei, Dongliang

2009-12-01

399

46 CFR 95.17-15 - Piping.  

Code of Federal Regulations, 2010 CFR

...of this chapter. (b) All piping, valves, and fittings of...the Commandant. (c) All piping, valves, and fittings shall...protected against injury. (d) Drains and dirt traps shall be fitted...of dirt or moisture. (e) Piping shall be used for no other...

2010-10-01

400

46 CFR 76.17-15 - Piping.  

Code of Federal Regulations, 2010 CFR

...of this chapter. (b) All piping, valves, and fittings of...the Commandant. (c) All piping, valves, and fittings shall...protected against injury. (d) Drains and dirt traps shall be fitted...of dirt or moisture. (e) Piping shall be used for no other...

2010-10-01

401

46 CFR 108.447 - Piping.  

Code of Federal Regulations, 2011 CFR

...108.447 Piping. (a) Each pipe, valve, and fitting in a CO2...80 (extra heavy). (c) Each pipe, valve, and fitting made of ferrous...CO2 system must have drains and dirt traps located where dirt or moisture can accumulate in...

2011-10-01

402

46 CFR 182.455 - Fuel piping.  

Code of Federal Regulations, 2010 CFR

...fuel lines, including pipe, tube, and hose, must...such as seamless steel pipe or tubing, which provide...fuel lines, including pipe, tube, and hose, must...at the tank is located inside the machinery space...of opening on top for cleaning screens. A drip...

2010-10-01

403

46 CFR 182.455 - Fuel piping.  

Code of Federal Regulations, 2011 CFR

...fuel lines, including pipe, tube, and hose, must...such as seamless steel pipe or tubing, which provide...fuel lines, including pipe, tube, and hose, must...at the tank is located inside the machinery space...of opening on top for cleaning screens. A drip...

2011-10-01

404

46 CFR 119.455 - Fuel piping.  

Code of Federal Regulations, 2011 CFR

...fuel lines, including pipe, tube, and hose, must...such as seamless steel pipe or tubing, which provide...fuel lines, including pipe, tube, and hose, must...at the tank is located inside the tank compartment...type opening on top for cleaning screens. Fuel...

2011-10-01

405

46 CFR 119.455 - Fuel piping.  

Code of Federal Regulations, 2010 CFR

...fuel lines, including pipe, tube, and hose, must...such as seamless steel pipe or tubing, which provide...fuel lines, including pipe, tube, and hose, must...at the tank is located inside the tank compartment...type opening on top for cleaning screens. Fuel...

2010-10-01

406

Assessment of socket weld integrity in pipings  

Microsoft Academic Search

The operating experience showed that the fatigue is one of the major piping failure mechanisms in nuclear power plants (NPPs). The pressure and\\/or temperature loading transients, the vibration, and the mechanical cyclic loading during the plant operation may induce the fatigue failure in the nuclear piping. Recently, many fatigue piping failure occurred at the socket weld area have been widely

Young Hwan Choi; Sun Yeong Choi

2009-01-01

407

FIELD STUDIES OF IMPREGNATED CONCRETE PIPE  

EPA Science Inventory

The follow-on study (initiated in June 1980) continued to monitor performance of 1,400 ft of impregnated concrete pipe installed in several Texas cities. The performance of concrete pipe has been compared with that of sulfur-impregnated concrete pipe; hydrofluoric acid (HF)-treat...

408

Heat pipes for sun energy conversion  

Microsoft Academic Search

Heat pipes fabricated from copper and employing organic fluids or water as the working fluid have been developed for use with solar collectors. The gravity pipes were tested for operation at angles of inclination from 0 to 90 deg. A porous structure (glass wool) was adopted to assure efficient circulation of the fluid. Data for heat pipes tested with acetone,

Z. Murgu; D. Murgu; L. Cojocaru; M. Huzum; E. Tvardochlieb

1978-01-01

409

Thermal Performance of High Temperature Titanium -- Water Heat Pipes by Multiple Heat Pipe Manufacturers  

NASA Technical Reports Server (NTRS)

Titanium - water heat pipes are being investigated for use in heat rejection systems for lunar and Mars fission surface power systems. Heat pipes provide an efficient and reliable means to transfer heat to a radiator heat rejection system. NASA Glenn Research Center requisitioned nine titanium water heat pipes from three vendors. Each vendor supplied three heat pipes 1.25 cm diameter by 1.1 meter long with each vendor selecting a different wick design. Each of the three heat pipes is slightly different in construction. Additional specifications for the heat pipes included 500 K nominal operating temperature, light weight, and freeze tolerance. The heat pipes were performance tested gravity-aided, in the horizontal position and at elevations against gravity at 450 K and 500 K. Performance of the three heat pipes is compared. The heat pipe data will be used to verify models of heat pipe radiators that will be used in future space exploration missions.

Sanzi, James L.

2007-01-01

410

Thermal Performance of High Temperature Titanium-Water Heat Pipes by Multiple Heat Pipe Manufacturers  

NASA Technical Reports Server (NTRS)

Titanium-water heat pipes are being investigated for use in heat rejection systems for lunar and Mars fission surface power systems. Heat pipes provide an efficient and reliable means to transfer heat to a radiator heat rejection system. NASA Glenn Research Center requisitioned nine titanium water heat pipes from three vendors. Each vendor supplied three heat pipes 1.25 cm diameter by 1.1 meter long with each vendor selecting a different wick design. Each of the three heat pipes is slightly different in construction. Additional specifications for the heat pipes included 500 K nominal operating temperature, light weight, and freeze tolerance. The heat pipes were performance tested gravity-aided, in the horizontal position and at elevations against gravity at 450 and 500 K. Performance of the three heat pipes is compared. The heat pipe data will be used to verify models of heat pipe radiators that will be used in future space exploration missions.

Sanzi, James L.

2007-01-01

411

Glassy Chimeras Could Be Blind to Quantum Speedup: Designing Better Benchmarks for Quantum Annealing Machines  

NASA Astrophysics Data System (ADS)

Recently, a programmable quantum annealing machine has been built that minimizes the cost function of hard optimization problems by, in principle, adiabatically quenching quantum fluctuations. Tests performed by different research teams have shown that, indeed, the machine seems to exploit quantum effects. However, experiments on a class of random-bond instances have not yet demonstrated an advantage over classical optimization algorithms on traditional computer hardware. Here, we present evidence as to why this might be the case. These engineered quantum annealing machines effectively operate coupled to a decohering thermal bath. Therefore, we study the finite-temperature critical behavior of the standard benchmark problem used to assess the computational capabilities of these complex machines. We simulate both random-bond Ising models and spin glasses with bimodal and Gaussian disorder on the D-Wave Chimera topology. Our results show that while the worst-case complexity of finding a ground state of an Ising spin glass on the Chimera graph is not polynomial, the finite-temperature phase space is likely rather simple because spin glasses on Chimera have only a zero-temperature transition. This means that benchmarking optimization methods using spin glasses on the Chimera graph might not be the best benchmark problems to test quantum speedup. We propose alternative benchmarks by embedding potentially harder problems on the Chimera topology. Finally, we also study the (reentrant) disorder-temperature phase diagram of the random-bond Ising model on the Chimera graph and show that a finite-temperature ferromagnetic phase is stable up to 19.85(15)% antiferromagnetic bonds. Beyond this threshold, the system only displays a zero-temperature spin-glass phase. Our results therefore show that a careful design of the hardware architecture and benchmark problems is key when building quantum annealing machines.

Katzgraber, Helmut G.; Hamze, Firas; Andrist, Ruben S.

2014-04-01

412

Glassy Chimeras could be blind to quantum speedup: Designing better benchmarks for quantum annealing machines  

E-print Network

Recently, a programmable quantum annealing machine has been built that minimizes the cost function of hard optimization problems by adiabatically quenching quantum fluctuations. Tests performed by different research teams have shown that, indeed, the machine seems to exploit quantum effects. However experiments on a class of random-bond instances have not yet demonstrated an advantage over classical optimization algorithms on traditional computer hardware. Here we present evidence as to why this might be the case. These engineered quantum annealing machines effectively operate coupled to a decohering thermal bath. Therefore, we study the finite-temperature critical behavior of the standard benchmark problem used to assess the computational capabilities of these complex machines. We simulate both random-bond Ising models and spin glasses with bimodal and Gaussian disorder on the D-Wave Chimera topology. Our results show that while the worst-case complexity of finding a ground state of an Ising spin glass on the Chimera graph is not polynomial, the finite-temperature phase space is likely rather simple: Spin glasses on Chimera have only a zero-temperature transition. This means that benchmarking optimization methods using spin glasses on the Chimera graph might not be the best benchmark problems to test quantum speedup. We propose alternative benchmarks by embedding potentially harder problems on the Chimera topology. Finally, we also study the (reentrant) disorder-temperature phase diagram of the random-bond Ising model on the Chimera graph and show that a finite-temperature ferromagnetic phase is stable up to 19.85(15)% antiferromagnetic bonds. Beyond this threshold the system only displays a zero-temperature spin-glass phase. Our results therefore show that a careful design of the hardware architecture and benchmark problems is key when building quantum annealing machines.

Helmut G. Katzgraber; Firas Hamze; Ruben S. Andrist

2014-01-07

413

Strong quantitative benchmarking of quantum optical devices  

SciTech Connect

Quantum communication devices, such as quantum repeaters, quantum memories, or quantum channels, are unavoidably exposed to imperfections. However, the presence of imperfections can be tolerated, as long as we can verify that such devices retain their quantum advantages. Benchmarks based on witnessing entanglement have proven useful for verifying the true quantum nature of these devices. The next challenge is to characterize how strongly a device is within the quantum domain. We present a method, based on entanglement measures and rigorous state truncation, which allows us to characterize the degree of quantumness of optical devices. This method serves as a quantitative extension to a large class of previously known quantum benchmarks, requiring no additional information beyond what is already used for the nonquantitative benchmarks.

Killoran, N.; Luetkenhaus, N. [Institute for Quantum Computing and Department of Physics and Astronomy, University of Waterloo, Waterloo, N2L 3G1 (Canada)

2011-05-15

414

Benchmark field study of deep neutron penetration  

SciTech Connect

A unique benchmark neutron field has been established at the Lawrence Livermore National Laboratory (LLNL) to study deep penetration neutron transport. At LLNL, a tandem accelerator is used to generate a monoenergetic neutron source that permits investigation of deep neutron penetration under conditions that are virtually ideal to model, namely the transport of mono-energetic neutrons through a single material in a simple geometry. General features of the Lawrence Tandem (LATAN) benchmark field are described with emphasis on neutron source characteristics and room return background. The single material chosen for the first benchmark, LATAN-1, is a steel representative of Light Water Reactor (LWR) Pressure Vessels (PV). Also included is a brief description of the Little Boy replica, a critical reactor assembly designed to mimic the radiation doses from the atomic bomb dropped on Hiroshima, and its us in neutron spectrometry. 18 refs.

Morgan, J.F.; Sale, K. (Lawrence Livermore National Lab., CA (USA)); Gold, R.; Roberts, J.H.; Preston, C.C. (Metrology Control Corp., Richland, WA (USA))

1991-06-10

415

Transient, turbulent, smooth pipe friction  

Microsoft Academic Search

Two of the most promising analytical models of unsteady friction in turbulent pipe flows are based on sharply contrasting hypotheses. One uses the history of the flow; the other uses instantaneous conditions. The purposes of this paper are to present an analysis using the former approach and to indicate how to determine which of the two methods is appropriate.A weighting

Alan E. Vardy; Jim M. B. Brown

1995-01-01

416

Characterization of accelerating pipe flow  

Microsoft Academic Search

A unique series of experiments was conducted to determine the effects of constant acceleration on the flow in a 5-cm-diameter pipe. These experiments, which differed substantially from those of previous researchers, investigated such phenomena as transition to turbulence and the general physics of the effect acceleration has on various flow parameters such as wall shear stress, velocity profile, and turbulence

Paul J. Lefebvre

1988-01-01

417

Characterization of accelerating pipe flow  

Microsoft Academic Search

A unique series of experiments was conducted to determine the effects of constant acceleration on the flow in a 5-cm diameter pipe. These experiments, which differed substantially from those of previous researchers, investigated such phenomena as transition to turbulence and the general physics of the effect acceleration has on various flow parameters such as well shear stress, velocity profile, and

1987-01-01

418

Ceramic heat pipe heat exchangers  

Microsoft Academic Search

High-temperature strength, resistance to corrosive atmospheres, and moderate cost combine to make ceramic materials an obvious choice for construction of high-temperature thermal energy recuperator systems. Despite these advantages, ceramic recuperators are steadily being replaced by metallic units at considerable sacrifice in maximum air or fuel preheat temperatures and hence in recovery efficiency. By constructing a recuperator from ceramic heat pipes,

W. A. Ranken

1976-01-01

419

Understanding the Response of Pipe-in-pipe Deepwater Riser Systems  

Microsoft Academic Search

Pipe-in-pipe top tensioned risers, in the forms of TLP\\/Spar dry tree risers and freestanding hybrid risers, are used in numerous deepwater developments worldwide. During the detail design of pipe-in-pipe systems, the complex interactions between the pipes are often misunderstood, leading to conservatism or possible errors in the estimation of the system fatigue life. This paper aims to provide an explanatory

I. Harrison

2007-01-01

420

Radiant heating tests of several liquid metal heat-pipe sandwich panels  

NASA Technical Reports Server (NTRS)

Integral heat-pipe sandwich panels, which synergistically combine the thermal efficiency of heat pipes and the structural efficiency of honeycomb sandwich construction, were conceived as a means of alleviating thermal stress problems in the Langley Scramjet Engine. Test panels which utilized two different wickable honeycomb cores, facesheets with screen mesh sintered to the internal surfaces, and a liquid metal working fluid (either sodium or potassium) were tested by radiant heating at various heat-load levels. The heat-pipe panels reduced maximum temperature differences by 31 percent with sodium working fluid and 45 percent with potassium working fluid. Results indicate that a heat-pipe sandwich panel is a potential, simple solution to the engine thermal stress problem. Other interesting applications of the concept include: cold plates for electronic component and circuit card cooling, radiators for large space platforms, low-distortion large area structures (e.g., space antennas) and laser mirrors.

Camarda, C. J.; Basiulis, A.

1983-01-01

421

Radiant heating tests of several liquid metal heat-pipe sandwich panels  

SciTech Connect

Integral heat pipe sandwich panels, which synergistically combine the thermal efficiency of heat pipes and the structural efficiency of honeycomb sandwich construction, were conceived as a means of alleviating thermal stress problems in the Langley Scramjet Engine. Test panels which utilized two different wickable honeycomb cores, facesheets with screen mesh sintered to the internal surfaces, and a liquid metal working fluid (either sodium or potassium) were tested by radiant heating at various heat load levels. The heat pipe panels reduced maximum temperature differences by 31 percent with sodium working fluid and 45 percent with potassium working fluid. Results indicate that a heat pipe sandwich panel is a potential, simple solution to the engine thermal stress problem. Other interesting applications of the concept include: cold plates for electronic component and circuit card cooling, radiators for large space platforms, low distortion large area structures (e.g., space antennas) and laser mirrors.

Camarda, C.J.; Basiulis, A.

1983-08-01

422

Radiant heating tests of several liquid metal heat-pipe sandwich panels  

NASA Technical Reports Server (NTRS)

Integral heat pipe sandwich panels, which synergistically combine the thermal efficiency of heat pipes and the structural efficiency of honeycomb sandwich construction, were conceived as a means of alleviating thermal stress problems in the Langley Scramjet Engine. Test panels which utilized two different wickable honeycomb cores, facesheets with screen mesh sintered to the internal surfaces, and a liquid metal working fluid (either sodium or potassium) were tested by radiant heating at various heat load levels. The heat pipe panels reduced maximum temperature differences by 31 percent with sodium working fluid and 45 percent with potassium working fluid. Results indicate that a heat pipe sandwich panel is a potential, simple solution to the engine thermal stress problem. Other interesting applications of the concept include: cold plates for electronic component and circuit card cooling, radiators for large space platforms, low distortion large area structures (e.g., space antennas) and laser mirrors.

Camarda, C. J.; Basiulis, A.

1983-01-01

423

Benchmarking of Heavy Ion Transport Codes  

SciTech Connect

Accurate prediction of radiation fields generated by heavy ion interactions is important in medical applications, space missions, and in designing and operation of rare isotope research facilities. In recent years, several well-established computer codes in widespread use for particle and radiation transport calculations have been equipped with the capability to simulate heavy ion transport and interactions. To assess and validate these capabilities, we performed simulations of a series of benchmark-quality heavy ion experiments with the computer codes FLUKA, MARS15, MCNPX, and PHITS. We focus on the comparisons of secondary neutron production. Results are encouraging; however, further improvements in models and codes and additional benchmarking are required.

Remec, Igor [ORNL] [ORNL; Ronningen, Reginald M. [Michigan State University, East Lansing] [Michigan State University, East Lansing; Heilbronn, Lawrence [University of Tennessee, Knoxville (UTK)] [University of Tennessee, Knoxville (UTK)

2011-01-01

424

Toxicological benchmarks for wildlife: 1996 Revision  

SciTech Connect

The purpose of this report is to present toxicological benchmarks for assessment of effects of certain chemicals on mammalian and avian wildlife species. Publication of this document meets a milestone for the Environmental Restoration (ER) Risk Assessment Program. This document provides the ER Program with toxicological benchmarks that may be used as comparative tools in screening assessments as well as lines of evidence to support or refute the presence of ecological effects in ecological risk assessments. The chemicals considered in this report are some that occur at US DOE waste sites, and the wildlife species evaluated herein were chosen because they represent a range of body sizes and diets.

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

1996-06-01

425

Los Alamos National Laboratory computer benchmarking 1982  

SciTech Connect

Evaluating the performance of computing machinery is a continual effort of the Computer Research and Applications Group of the Los Alamos National Laboratory. This report summarizes the results of the group's benchmarking activities performed between October 1981 and September 1982, presenting compilation and execution times as well as megaflop rates for a set of benchmark codes. Tests were performed on the following computers: Cray Research, Inc. (CRI) Cray-1S; Control Data Corporation (CDC) 7600, 6600, Cyber 73, Cyber 825, Cyber 835, Cyber 855, and Cyber 205; Digital Equipment Corporation (DEC) VAX 11/780 and VAX 11/782; and Apollo Computer, Inc., Apollo.

Martin, J.L.

1983-06-01

426

Collected notes from the Benchmarks and Metrics Workshop  

NASA Technical Reports Server (NTRS)

In recent years there has been a proliferation of proposals in the artificial intelligence (AI) literature for integrated agent architectures. Each architecture offers an approach to the general problem of constructing an integrated agent. Unfortunately, the ways in which one architecture might be considered better than another are not always clear. There has been a growing realization that many of the positive and negative aspects of an architecture become apparent only when experimental evaluation is performed and that to progress as a discipline, we must develop rigorous experimental methods. In addition to the intrinsic intellectual interest of experimentation, rigorous performance evaluation of systems is also a crucial practical concern to our research sponsors. DARPA, NASA, and AFOSR (among others) are actively searching for better ways of experimentally evaluating alternative approaches to building intelligent agents. One tool for experimental evaluation involves testing systems on benchmark tasks in order to assess their relative performance. As part of a joint DARPA and NASA funded project, NASA-Ames and Teleos Research are carrying out a research effort to establish a set of benchmark tasks and evaluation metrics by which the performance of agent architectures may be determined. As part of this project, we held a workshop on Benchmarks and Metrics at the NASA Ames Research Center on June 25, 1990. The objective of the workshop was to foster early discussion on this important topic. We did not achieve a consensus, nor did we expect to. Collected here is some of the information that was exchanged at the workshop. Given here is an outline of the workshop, a list of the participants, notes taken on the white-board during open discussions, position papers/notes from some participants, and copies of slides used in the presentations.

Drummond, Mark E.; Kaelbling, Leslie P.; Rosenschein, Stanley J.

1991-01-01

427

Heat pipes in space and on earth  

NASA Technical Reports Server (NTRS)

The performance of heat pipes used in the thermal control system of spacecraft such as OAO-III and ATS-6 is discussed, and applications of heat pipes to permafrost stabilization on the Alaska Pipeline and to heat recovery systems are described. Particular attention is given to the ATS-6, launched in 1974, which employs 55 heat pipes to carry solar and internal power loads to radiator surfaces. In addition, experiments involving radiative cooling based on cryogenic heat pipes have been planned for the Long Duration Exposure Facility spacecraft and for Spacelab. The role of heat pipes in Space Shuttle heat rejection services is also mentioned.

Ollendorf, S.

1978-01-01

428

Rusty pipe syndrome, a cause of bloody nipple discharge: case report.  

PubMed

Abstract Breastfeeding has universally known advantages to the mother and child that include nutritional and immunological benefits but also involve reasons of ecological and economic order. Initiation and maintenance of breastfeeding can be associated with common problems. The beginning of milk production may course with bloody nipple discharge, which, after exclusion of pathological entities, concerns a self-resolving physiological syndrome called rusty pipe. We present a case of rusty pipe syndrome and discuss the implications. PMID:24964086

Silva, Joana Raquel; Carvalho, Rita; Maia, Catarina; Osrio, Marta; Barbosa, Marta

2014-10-01

429

Practical aspects of acoustic plastic pipe location  

SciTech Connect

Many gas distribution company operation and maintenance activities require precise knowledge of the location of buried plastic piping. Plastic pipe cannot be located if the tracer wire is gone or was never installed. Under sponsorship of the Southern California Gas Company, IGT successfully demonstrated an acoustic plastic pipe location technique and is developing the technique into a practical field instrument an acoustic signal is injected directly into the gas at a service. The acoustic signal travels in the gas in the pipes, not in the pipe wall. As the acoustic wave travels along the pipe, some of the sound radiates from the pipe through the soil to the surface of the ground. An array of sensors on the surface of the ground perpendicular to the pipe detects the acoustic signal, thereby locating the Pipe. Two different acoustic measurements are used. The first measurement locates the pipe to within {plus_minus} 3-ft. Then the second technique determines the location of the pipe to within {plus_minus} 6-in.

Huebler, J.E.; Campbell, B.K. [Institute of Gas Technology, Chicago, IL (United States); Ching, G.K. [Southern California Gas Co. (United States)

1993-12-31

430

SAFE Alkali Metal Heat Pipe Reliability  

NASA Astrophysics Data System (ADS)

Alkali metal heat pipes are among the best understood and tested of components for first generation space fission reactors. A flight reactor will require production of a hundred or more heat pipes with assured reliability over a number of years. To date, alkali metal heat pipes have been built mostly in low budget development environments with little formal quality assurance. Despite this, heat pipe test samples suggest that high reliability can be achieved with the care justified for space flight qualification. Fabrication procedures have been established that, if consistently applied, ensure long-term trouble-free heat pipe operation. Alkali metal heat pipes have been successfully flight tested in micro gravity and also have been shown capable of multi-year operation with no evidence of sensitivity to fast neutron fluence up to 1023 n/cm2. This represents 50 times the fluence of the proposed Safe Affordable Fission Engine (SAFE-100) heat pipe reactor core.

Reid, Robert S.

2003-01-01

431

Ultrasonic pipe inspection prove-ups can be improved  

SciTech Connect

In extensive tests conducted in its laboratories, Lone Star Steel found conventional manual ultrasonic prove-ups of pipe imperfections to be consistently inaccurate. Error rates ranged from 65% to 100%. On an average, the author found that of every five joints of casing rejected by manual prove-ups, four did not have rejectable imperfections. In many cases, the rejected pipe cost several thousand dollars a joint. The cost of rejecting acceptable pipe is not one pipe manufacturer can simply absorb. Buyers eventually pay the cost by paying higher overall prices. Yet, this research shows unnecessary rejection is a cost that can be easily eliminated by making simple changes in conventional ultrasonic prove-up procedures. The proposed changes do not involve loosening existing standards. But the author are convinced that it is to the oil and gas industry's best interests to ensure prove-up procedures produce accurate and repeatable results. The paper describes current inspection practices, indications of problems, the variable calibration notch, the variable wedge, the wrong transducer, the advantage of one-half inch transducers, surface preparation, common misconceptions, and recommendations.

Hodges, B.J. (Lone Star Steel, Lone Star, TX (United States))

1993-09-13

432

Scheduling algorithms for PIPE (Pipelined Image-Processing Engine)  

SciTech Connect

In this paper the authors present heuristic scheduling algorithms for the National Bureau of Standards/Aspex Inc. Pipelined Image-Processing Engine (PIPE). PIPE is a special-purpose machine for low-level image processing consisting of a linearly connected array of processing stages. A program is specified as a direct acyclic graph (DAG). The authors' first algorithm schedules planar DAGs. It works top-down through the graph and uses the greedy approach to schedule operations on a stage. It uses several heuristics to control the movement of images between stages. The worst case time for the schedule generated by the algorithm is O(N) times the optimal schedule, where N is the maximum width of the graph. The authors generalize this algorithm to work on nonplanar graphs, using heuristics for repositioning images on the stages of PIPE. The worst case time for the more general algorithm is also O(N) times the optimal schedule. Finally, the authors analyze the problem of optimizing throughput and latency for a sequence of DAGs on PIPE.

Stewart, C.V.; Dyer, C.R.

1988-04-01

433

Ultrasonic multi-skip tomography for pipe inspection  

NASA Astrophysics Data System (ADS)

The inspection of wall loss corrosion is difficult at pipe supports due to limited accessibility. The recently developed ultrasonic Multi-Skip screening technique is suitable for this problem. The method employs ultrasonic transducers in a pitch-catch geometry positioned on opposite sides of the pipe support. Shear waves are transmitted in the axial direction within the pipe wall, reflecting multiple times between the inner and outer surfaces before reaching the receivers. Along this path, the signals accumulate information on the integral wall thickness (e.g., via variations in travel time). The method is very sensitive in detecting the presence of wall loss, but it is difficult to quantify both the extent and depth of the loss. Multi-skip tomography has been developed to reconstruct the wall thickness profile along the axial direction of the pipe. The method uses model-based full wave field inversion; this consists of a forward model for predicting the measured wave field and an iterative process that compares the predicted and measured wave fields and minimizes the differences with respect to the model parameters (i.e., the wall thickness profile). Experimental results are very encouraging. Various defects (slot and flat bottom hole) are reconstructed using the tomographic inversion. The general shape and width are well recovered. The current sizing accuracy is in the order of 1 mm.

Volker, Arno; van Zon, Tim

2014-02-01

434

Completing Quasigroups or Latin Squares: A Structured Graph Coloring Problem  

Microsoft Academic Search

We introduce a graph coloring challenge benchmark based on the problem of completing Latin squares. We show how the hardness of the instances can be finely controlled by varying the fraction of pre- colored squares. We compare three complete (exact) solution strategies on this benchmark: (1) a Constraint Satisfaction (CSP) based approach, (2) a hybrid Linear Programming \\/ CSP approach,

Carla P. Gomes; David Shmoys

435

Benchmarking Music Information Retrieval Systems Department of Electronic Engineering  

E-print Network

Benchmarking Music Information Retrieval Systems Josh Reiss Department of Electronic Engineering and effective benchmarking system for music information retrieval (MIR) systems. This will serve the multiple surrounding retrieval of audio in test collections. 1. INTRODUCTION The Music Information Retrieval (MIR

Reiss, Josh

436

29 CFR 1952.153 - Compliance staffing benchmarks.  

Code of Federal Regulations, 2010 CFR

...North Carolina 1952.153 Compliance staffing benchmarks. Under the terms of the 1978 Court Order in AFL-CIO v. Marshall, compliance staffing levels (benchmarks) necessary for a fully effective enforcement program...

2010-07-01

437

29 CFR 1952.113 - Compliance staffing benchmarks.  

Code of Federal Regulations, 2010 CFR

...STANDARDS Utah 1952.113 Compliance staffing benchmarks. Under the terms of the 1978 Court Order in AFL-CIO v. Marshall, compliance staffing levels (benchmarks) necessary for a fully effective enforcement program were...

2010-07-01

438

7 CFR 1709.5 - Determination of energy cost benchmarks.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 false Determination of energy cost benchmarks. 1709.5 Section...OF AGRICULTURE ASSISTANCE TO HIGH ENERGY COST COMMUNITIES General Requirements 1709.5 Determination of energy cost benchmarks. (a) The...

2011-01-01

439

7 CFR 1709.5 - Determination of energy cost benchmarks.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Determination of energy cost benchmarks. 1709.5 Section...OF AGRICULTURE ASSISTANCE TO HIGH ENERGY COST COMMUNITIES General Requirements 1709.5 Determination of energy cost benchmarks. (a) The...

2010-01-01

440

29 CFR 1952.103 - Compliance staffing benchmarks.  

Code of Federal Regulations, 2011 CFR

...PLANS FOR ENFORCEMENT OF STATE STANDARDS Oregon 1952.103 Compliance staffing benchmarks...approved State plan. In October 1992, Oregon completed, in conjunction with OSHA...benchmark of 28 health compliance officers. Oregon elected to retain the safety...

2011-07-01

441

29 CFR 1952.103 - Compliance staffing benchmarks.  

Code of Federal Regulations, 2013 CFR

...PLANS FOR ENFORCEMENT OF STATE STANDARDS Oregon 1952.103 Compliance staffing benchmarks...approved State plan. In October 1992, Oregon completed, in conjunction with OSHA...benchmark of 28 health compliance officers. Oregon elected to retain the safety...

2013-07-01

442

29 CFR 1952.103 - Compliance staffing benchmarks.  

Code of Federal Regulations, 2012 CFR

...PLANS FOR ENFORCEMENT OF STATE STANDARDS Oregon 1952.103 Compliance staffing benchmarks...approved State plan. In October 1992, Oregon completed, in conjunction with OSHA...benchmark of 28 health compliance officers. Oregon elected to retain the safety...

2012-07-01

443

29 CFR 1952.103 - Compliance staffing benchmarks.  

Code of Federal Regulations, 2010 CFR

...PLANS FOR ENFORCEMENT OF STATE STANDARDS Oregon 1952.103 Compliance staffing benchmarks...approved State plan. In October 1992, Oregon completed, in conjunction with OSHA...benchmark of 28 health compliance officers. Oregon elected to retain the safety...

2010-07-01

444

Why and how to benchmark XML databases  

Microsoft Academic Search

Benchmarks belong to the very standard repertory of tools deployed in database development. Assessing the capabilities of a system, analyzing actual and potential bottlenecks, and, naturally, comparing the pros and cons of different systems architectures have become indispensable tasks as databases management systems grow in complexity and capacity. In the course of the development of XML databases the need for

Albrecht Schmidt; Florian Waas; Martin L. Kersten; Daniela Florescu; Michael J. Carey; Ioana Manolescu; Ralph Busse

2001-01-01

445

Benchmark Generation using Domain Specific Modeling  

SciTech Connect

Performance benchmarks are domain specific applications that are specialized to a certain set of technologies and platforms. The development of a benchmark application requires mapping the performance specific domain concepts to an implementation and producing complex technology and platform specific code. Domain Specific Modeling (DSM) promises to bridge the gap between application domains and implementations by allowing designers to specify solutions in domain-specific abstractions and semantics through Domain Specific Languages (DSL). This allows generation of a final implementation automatically from high level models. The modeling and task automation benefits obtained from this approach usually justify the upfront cost involved. This paper employs a DSM based approach to invent a new DSL, DSLBench, for benchmark generation. DSLBench and its associated code generation facilities allow the design and generation of a completely deployable benchmark application for performance testing from a high level model. DSLBench is implemented using Microsoft Domain Specific Language toolkit. It is integrated with the Visual Studio 2005 Team Suite as a plug-in to provide extra modeling capabilities for performance testing. We illustrate the approach using a case study based on .Net and C#.

Bui, Ngoc B.; Zhu, Liming; Gorton, Ian; Liu, Yan

2007-08-01

446

Benchmarking in Universities: League Tables Revisited  

ERIC Educational Resources Information Center

This paper examines the practice of benchmarking universities using a "league table" approach. Taking the example of the "Sunday Times University League Table", the author reanalyses the descriptive data on UK universities. Using a linear programming technique, data envelope analysis (DEA), the author uses the re-analysis to demonstrate the major

Turner, David

2005-01-01

447

Benchmarking 2011: Trends in Education Philanthropy  

ERIC Educational Resources Information Center

The analysis in "Benchmarking 2011" is based on data from an unduplicated sample of 184 education grantmaking organizations--approximately two-thirds of Grantmakers for Education's (GFE's) network of grantmakers--who responded to an online survey consisting of fixed-choice and open-ended questions. Because a different subset of funders elects to

Grantmakers for Education, 2011

2011-01-01

448

What Is the Impact of Subject Benchmarking?  

ERIC Educational Resources Information Center

The introduction of subject benchmarking led to fears of increased external intervention in the activities of universities and a more restrictive view of institutional autonomy, accompanied by an undermining of the academic profession, particularly through the perceived threat of the introduction of a national curriculum for higher education. For

Pidcock, Steve

2006-01-01

449

Simulation of Computer Architectures: Simulators, Benchmarks, Methodologies,  

E-print Network

Simulation of Computer Architectures: Simulators, Benchmarks, Methodologies, and Recommendations Joshua J. Yi, Member, IEEE, and David J. Lilja, Fellow, IEEE Abstract--Simulators have become an integral the efficacy of an enhancement. However, long simulation times and poor accuracy limit their effectiveness

Minnesota, University of

450

Benchmarking 2010: Trends in Education Philanthropy  

ERIC Educational Resources Information Center

"Benchmarking 2010" offers insights into the current priorities, practices and concerns of education grantmakers. The report is divided into five sections: (1) Mapping the Education Grantmaking Landscape; (2) 2010 Funding Priorities; (3) Strategies for Leveraging Greater Impact; (4) Identifying Significant Trends in Education Funding; and (5)

Bearman, Jessica

2010-01-01

451

Quality Benchmarks in Undergraduate Psychology Programs  

ERIC Educational Resources Information Center

Performance benchmarks are proposed to assist undergraduate psychology programs in defining their missions and goals as well as documenting their effectiveness. Experienced academic program reviewers compared their experiences to formulate a developmental framework of attributes of undergraduate programs focusing on activity in 8 domains:

Dunn, Dana S.; McCarthy, Maureen A.; Baker, Suzanne; Halonen, Jane S.; Hill, G. William, IV

2007-01-01

452

Modelling an Inertia Wheel Pendulum Benchmark  

Microsoft Academic Search

In this paper, modelling and parameter identification of an inertia wheel pendulum benchmark is considered. This is an underactuated mechanical system useful for teaching and research. Attention is focused on deriving a simple but accurate model capable of reproducing large amplitude oscillations. Due to the particular design of the prototype, the friction forces on the actuated joint are noticeable. A

Diego Alonso; Federico Robbio; Eduardo Paolini; Jorge Moiola

2005-01-01

453

Benchmarks--Standards Comparisons. Math Competencies: EFF Benchmarks Comparison [and] Reading Competencies: EFF Benchmarks Comparison [and] Writing Competencies: EFF Benchmarks Comparison.  

ERIC Educational Resources Information Center

This document is intended to show the relationship between Ohio's Standards and Competencies, Equipped for the Future's (EFF's) Standards and Components of Performance, and Ohio's Revised Benchmarks. The document is divided into three parts, with Part 1 covering mathematics instruction, Part 2 covering reading instruction, and Part 3 covering

Kent State Univ., OH. Ohio Literacy Resource Center.

454

Communication Characteristics in the NAS Parallel Benchmarks  

E-print Network

) implementation of the NAS parallel benchmarks and study the effectiveness of com- piled communication for MPI, the effectiveness of compiled communication de- pends on whether the communication information can be ob- tained of MPI, it is important to study the communications in MPI programs and determine the effectiveness

Yuan, Xin

455

A MULTIMODEL APPROACH FOR CALCULATING BENCHMARK DOSE  

EPA Science Inventory

A Multimodel Approach for Calculating Benchmark Dose Ramon I. Garcia and R. Woodrow Setzer In the assessment of dose response, a number of plausible dose- response models may give fits that are consistent with the data. If no dose response formulation had been speci...

456

Implementation of NAS Parallel Benchmarks in Java.  

National Technical Information Service (NTIS)

A number of features make Java an attractive but a debatable choice for High Performance Computing (HPC). In order to gauge the applicability of Java to the Computational Fluid Dynamics (CFD) we have implemented NAS Parallel Benchmarks in Java. The perfor...

M. Frumkin, M. Schultz, H. Q. Jin, J. Yan

2000-01-01

457

The nofib Benchmark Suite of Haskell Programs  

E-print Network

­ sheet­like example program, they do not report any actual measurements. How­ ever, they astutely take issue with the usual toy benchmarks: ``There was in the past a tendency for implementations to be judged the rage: marketeers bandied them about shamelessly, compiler writers tweaked their compilers to spot

Jones, Simon Peyton

458

Benchmarking the presidential election of Barack Obama  

Microsoft Academic Search

Purpose The purpose of this paper is to explore the range of benchmark applications associated with the historical event of Barack Obama being elected as the 44th US president. Design\\/methodology\\/approach Collection and critical analysis of secondary data from relevant publications analyzing the results of the 2008 presidential elections. Analysis of organizational behavior theories have been utilized in order

Daryl D. Green

2009-01-01

459

MHEC Survey Establishes Midwest Property Insurance Benchmarks.  

ERIC Educational Resources Information Center

This publication presents the results of a survey of over 200 midwestern colleges and universities on their property insurance programs and establishes benchmarks to help these institutions evaluate their insurance programs. Findings included the following: (1) 51 percent of respondents currently purchase their property insurance as part of a

Midwestern Higher Education Commission Risk Management Institute Research Bulletin, 1994

1994-01-01

460

Cleanroom Energy Efficiency: Metrics and Benchmarks  

SciTech Connect

Cleanrooms are among the most energy-intensive types of facilities. This is primarily due to the cleanliness requirements that result in high airflow rates and system static pressures, as well as process requirements that result in high cooling loads. Various studies have shown that there is a wide range of cleanroom energy efficiencies and that facility managers may not be aware of how energy efficient their cleanroom facility can be relative to other cleanroom facilities with the same cleanliness requirements. Metrics and benchmarks are an effective way to compare one facility to another and to track the performance of a given facility over time. This article presents the key metrics and benchmarks that facility managers can use to assess, track, and manage their cleanroom energy efficiency or to set energy efficiency targets for new construction. These include system-level metrics such as air change rates, air handling W/cfm, and filter pressure drops. Operational data are presented from over 20 different cleanrooms that were benchmarked with these metrics and that are part of the cleanroom benchmark dataset maintained by Lawrence Berkeley National Laboratory (LBNL). Overall production efficiency metrics for cleanrooms in 28 semiconductor manufacturing facilities in the United States and recorded in the Fabs21 database are also presented.

International SEMATECH Manufacturing Initiative; Mathew, Paul A.; Tschudi, William; Sartor, Dale; Beasley, James

2010-07-07

461

Sequenced Benchmarks for K-8 Science.  

ERIC Educational Resources Information Center

This document describes science benchmarks for grades K-8 in Earth and Space Science, Life Science, and Physical Science. Each subject area is divided into topics followed by a short content description and grade level information. Source documents for this paper included science content guides from California, Ohio, South Carolina, and South

Kendall, John S.; DeFrees, Keri L.; Richardson, Amy

462

Benchmarking Peer Production Mechanisms, Processes & Practices  

ERIC Educational Resources Information Center

This deliverable identifies key approaches for quality management in peer production by benchmarking peer production practices and processes in other areas. (Contains 29 footnotes, 13 figures and 2 tables.)[This report has been authored with contributions of: Kaisa Honkonen-Ratinen, Matti Auvinen, David Riley, Jose Pinzon, Thomas Fischer, Thomas

Fischer, Thomas; Kretschmer, Thomas

2008-01-01

463

Towards Benchmarks for Vision SLAM Algorithms  

Microsoft Academic Search

SLAM in an outdoor environment using natural landmarks stands as the holy grail of SLAM algorithms. Segmenting landmarks from background clutter in such environments is difficult and vision, rather than laser, has a higher potential to perform such tasks due to the higher bandwidth of information it carries. There is a need to establish a benchmark upon which emerging vision

Samer M. Abdallah; Daniel C. Asmar; John S. Zelek

2006-01-01

464

Results Oriented Benchmarking: The Evolution of Benchmarking at NASA from Competitive Comparisons to World Class Space Partnerships  

NASA Technical Reports Server (NTRS)

Informal benchmarking using personal or professional networks has taken place for many years at the Kennedy Space Center (KSC). The National Aeronautics and Space Administration (NASA) recognized early on, the need to formalize the benchmarking process for better utilization of resources and improved benchmarking performance. The need to compete in a faster, better, cheaper environment has been the catalyst for formalizing these efforts. A pioneering benchmarking consortium was chartered at KSC in January 1994. The consortium known as the Kennedy Benchmarking Clearinghouse (KBC), is a collaborative effort of NASA and all major KSC contractors. The charter of this consortium is to facilitate effective benchmarking, and leverage the resulting quality improvements across KSC. The KBC acts as a resource with experienced facilitators and a proven process. One of the initial actions of the KBC was to develop a holistic methodology for Center-wide benchmarking. This approach to Benchmarking integrates the best features of proven benchmarking models (i.e., Camp, Spendolini, Watson, and Balm). This cost-effective alternative to conventional Benchmarking approaches has provided a foundation for consistent benchmarking at KSC through the development of common terminology, tools, and techniques. Through these efforts a foundation and infrastructure has been built which allows short duration benchmarking studies yielding results gleaned from world class partners that can be readily implemented. The KBC has been recognized with the Silver Medal Award (in the applied research category) from the International Benchmarking Clearinghouse.

Bell, Michael A.

1999-01-01

465

System for Testing Thermal Insulation of Pipes  

NASA Technical Reports Server (NTRS)

An apparatus and method have been developed for measuring the rates of leakage of heat into pipes carrying liquids, the purpose of the measurements being to quantify the thermal performance of the insulation system. The apparatus is designed primarily for testing pipes used to carry cryogenic liquids, but can also be used for measuring the thermal performance of other insulated pipes or piping systems. The basic measurement principle is straightforward: The outer surface of the pipe insulation is maintained at a fixed warmer temperature. The interior of the pipe is maintained in a narrow fixed lower-temperature range by means of a regular liquid (e.g., water) that is pumped through the pipe at a known flow rate or a cryogenic liquid (e.g., nitrogen) that is saturated at atmospheric pressure and replenished until steady-state conditions are achieved. In the case of water or another liquid pumped through, the inlet and outlet temperatures are measured and heat-leak power is calculated as the mass flow rate of the liquid multiplied by the specific heat of the liquid multiplied by the inlet-to-outlet temperature rise of the liquid. In the case of liquid nitrogen or another low-temperature boiling liquid, the heat-leak power is calculated as the rate of boil-off multiplied by the latent heat of vaporization of the liquid. Then the thermal-insulation performance of the pipe system can be calculated as a function of the measured heat-leak power, the inner and outer boundary temperatures, and the dimensions of the pipe. The apparatus can test as many as three pipes simultaneously. The pipes can have inner diameters up to .15 cm and outer diameters up to .20 cm. The lengths of the pipes may vary; typical lengths are of the order of 18 m. Two thermal guard boxes . one for each end of the pipe(s) under test . are used to make the inlet and outlet fluid connections to the pipe(s) (see figure). The connections include bellows that accommodate thermal expansion and contraction of the pipes. The guard boxes and pipe(s) are positioned so that the pipe(s) slope upward from the upstream to the downstream end at an angle of at least 2 . The upward slope allows vapor bubbles to accumulate at the downstream end. The thermal guard boxes keep the ends of the pipes at the lower interior temperature to prevent spurious lengthwise leakage of heat into the pipes. It is important to prevent this spurious heat leakage because, if it were allowed to occur, it could contribute a large error in the measured heat-leak power. The upstream thermal guard box includes a heat exchanger through which liquid flowing into the pipe(s) is subcooled to the saturation temperature corresponding to the ambient pressure. Conversely, this heat exchanger can also be used to warm the flowing liquid to a desired fixed temperature. The apparatus includes a temperature control device that is placed around each pipe under test. Each device is operated under thermostatic control to maintain the outer surface of the pipe insulation at the specified test temperature. All measurements are recorded on a portable data-acquisition system.

Fesmire, James E.; Augustynowicz, Stanislaw D.; Nagy, Zoltan F.

2003-01-01

466

Benchmarking and developing numerical Finite Element models of volcanic deformation  

NASA Astrophysics Data System (ADS)

Volcanic deformation during an unrest episode can provide valuable insights into potential magmatic plumbing system dynamics. Paramount to this is a model linking the recorded ground movement to the causative source at depth. Most models employ analytical techniques due to their simplicity, but these are limited in their approach due to a number of necessary assumptions, and restricted to crude subsurface representations. We address this problem by providing guidelines and example model files to benchmark against a simple, analytical model with a numerical Finite Element approach using COMSOL Multiphysics. The boundary conditions should also be applicable to other Finite Element modeling packages. Then, due to the flexibility of the Finite Element method, this allows a progression of adding increasing complexities to reproduce the likely intricacies of the subsurface. We thus provide further guidelines and accompanying model files to incorporate subsurface heterogeneity, benchmarked viscoelastic rheology and temperature-dependent mechanics. In doing so, we highlight that setting up more integrated geodetic models is not particularly difficult and can alter inferred source characteristics and dynamics. The models are applied to Uturuncu volcano in southern Bolivia to demonstrate the approach.

Hickey, James; Gottsmann, Joachim

2014-06-01

467

CDx: a family of real-time Java benchmarks  

Microsoft Academic Search

Java is becoming a viable platform for hard real-time computing. There are production and research real-time Java VMs, as well as applications in both military and civil sector. Technological advances and increased adoption of Real-time Java contrast significantly with the lack of real-time benchmarks. The few benchmarks that exist are either low-level synthetic micro-benchmarks, or benchmarks used internally by companies,

Toms Kalibera; Jeff Hagelberg; Filip Pizlo; Ales Plsek; Ben Titzer; Jan Vitek

2009-01-01

468

The AM-Bench: An Android Multimedia Benchmark Suite  

E-print Network

The AM-Bench: An Android Multimedia Benchmark Suite Chayong Lee Euna Kim Hyesoon Kim School benchmark for Android platforms (AM-Bench). The AM-Bench consists of several multimedia benchmarks running on Android platforms. We explain the characteristics of the AM-Bench and compare performance on four Android

Lee, Hsien-Hsin "Sean"

469

Discovering and Implementing Best Practices to Strengthen SEAs: Collaborative Benchmarking  

ERIC Educational Resources Information Center

This paper is written for state educational agency (SEA) leaders who are considering the benefits of collaborative benchmarking, and it addresses the following questions: (1) What does benchmarking of best practices entail?; (2) How does "collaborative benchmarking" enhance the process?; (3) How do SEAs control the process so that "their" needs

Building State Capacity and Productivity Center, 2013

2013-01-01

470

NAS Grid Benchmarks: A Tool for Grid Space Exploration  

Microsoft Academic Search

We present a benchmark suite for computational grids in this paper. It is based on the NAS Parallel Benchmarks (NPB) and is called the NAS Grid Benchmark (NGB). 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

Michael A. Frumkin; Rob F. Van Der Wijngaart

2001-01-01

471

Taking Stock of Corporate Benchmarking Practices: Panacea or Pandora's Box?  

ERIC Educational Resources Information Center

Discusses why corporate communications/public relations (cc/pr) should be benchmarked (an approach used by cc/pr managers to demonstrate the value of their activities to skeptical organizational executives). Discusses myths about cc/pr benchmarking; types, targets, and focus of cc/pr benchmarking; a process model; and critical decisions about

Fleisher, Craig S.; Burton, Sara

1995-01-01

472

Heat Pipes for Alaskan Oil  

NASA Technical Reports Server (NTRS)

McDonnel Douglas Corporation is using a heat-pipe device, developed through the space program, to transport oil from Alaska's rich North Slope fields. It is being used to keep the ground frozen along the 798- mile pipeline saving hundreds of millions of dollars and protecting the tundra environment. Heatpipes are totally automatic, they sense and respond to climatic conditions with no moving parts, require no external power, and never need adjustment or servicing.

1976-01-01

473

Pipe Cleaning Operating Procedures  

SciTech Connect

This cleaning procedure outlines the steps involved in cleaning the high purity argon lines associated with the DO calorimeters. The procedure is broken down into 7 cycles: system setup, initial flush, wash, first rinse, second rinse, final rinse and drying. The system setup involves preparing the pump cart, line to be cleaned, distilled water, and interconnecting hoses and fittings. The initial flush is an off-line flush of the pump cart and its plumbing in order to preclude contaminating the line. The wash cycle circulates the detergent solution (Micro) at 180 degrees Fahrenheit through the line to be cleaned. The first rinse is then intended to rid the line of the majority of detergent and only needs to run for 30 minutes and at ambient temperature. The second rinse (if necessary) should eliminate the remaining soap residue. The final rinse is then intended to be a check that there is no remaining soap or other foreign particles in the line, particularly metal 'chips.' The final rinse should be run at 180 degrees Fahrenheit for at least 90 minutes. The filters should be changed after each cycle, paying particular attention to the wash cycle and the final rinse cycle return filters. These filters, which should be bagged and labeled, prove that the pipeline is clean. Only distilled water should be used for all cycles, especially rinsing. The level in the tank need not be excessive, merely enough to cover the heater float switch. The final rinse, however, may require a full 50 gallons. Note that most of the details of the procedure are included in the initial flush description. This section should be referred to if problems arise in the wash or rinse cycles.

Clark, D.; Wu, J.; /Fermilab

1991-01-24

474

Travelling waves in pipe flow and their relevance for transition to turbulence  

Microsoft Academic Search

The problem of understanding the nature of pressure-driven fluid flow through a circular straight pipe remains one of the oldest problems in fluid mechanics. The steady, unidirectional parabolic (laminar) flow solution named after Hagen (1839) and Poiseuille (1840) is linearly stable yet temporally and spatially disordered 3-dimensional (turbulent) solutions can easily be triggered at sufficiently large flow rates (Reynolds 1883).

Rich Kerswell

2006-01-01

475

Interim report on verification and benchmark testing of the NUFT computer code  

SciTech Connect

This interim report presents results of work completed in the ongoing verification and benchmark testing of the NUFT (Nonisothermal Unsaturated-saturated Flow and Transport) computer code. NUFT is a suite of multiphase, multicomponent models for numerical solution of thermal and isothermal flow and transport in porous media, with application to subsurface contaminant transport problems. The code simulates the coupled transport of heat, fluids, and chemical components, including volatile organic compounds. Grid systems may be cartesian or cylindrical, with one-, two-, or fully three-dimensional configurations possible. In this initial phase of testing, the NUFT code was used to solve seven one-dimensional unsaturated flow and heat transfer problems. Three verification and four benchmarking problems were solved. In the verification testing, excellent agreement was observed between NUFT results and the analytical or quasianalytical solutions. In the benchmark testing, results of code intercomparison were very satisfactory. From these testing results, it is concluded that the NUFT code is ready for application to field and laboratory problems similar to those addressed here. Multidimensional problems, including those dealing with chemical transport, will be addressed in a subsequent report.

Lee, K.H.; Nitao, J.J. [Lawrence Livermore National Lab., CA (United States