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1

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

SciTech Connect

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

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

1980-08-01

2

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

3

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

4

COG validation: SINBAD Benchmark Problems  

SciTech Connect

We validated COG, a 3D Monte Carlo radiation transport code, against experimental data and MNCP4C simulations from the Shielding Integral Benchmark Archive Database (SINBAD) compiled by RSICC. We modeled three experiments: the Osaka Nickel and Aluminum sphere experiments conducted at the OKTAVIAN facility, and the liquid oxygen experiment conducted at the FNS facility. COG results are in good agreement with experimental data and generally within a few % of MCNP results. There are several possible sources of discrepancy between MCNP and COG results: (1) the cross-section database versions are different, MCNP uses ENDFB VI 1.1 while COG uses ENDFB VIR7, (2) the code implementations are different, and (3) the models may differ slightly. We also limited the use of variance reduction methods when running the COG version of the problems.

Lent, E M; Sale, K E; Buck, R M; Descalle, M

2004-02-23

5

COG validation: SINBAD Benchmark Problems  

Microsoft Academic Search

We validated COG, a 3D Monte Carlo radiation transport code, against experimental data and MNCP4C simulations from the Shielding Integral Benchmark Archive Database (SINBAD) compiled by RSICC. We modeled three experiments: the Osaka Nickel and Aluminum sphere experiments conducted at the OKTAVIAN facility, and the liquid oxygen experiment conducted at the FNS facility. COG results are in good agreement with

E M Lent; K E Sale; R M Buck; M Descalle

2004-01-01

6

Calculator solves pipe flow problems  

SciTech Connect

For facilitating pipe-flow calculations that involve the horizontal flow of constant-density fluids, a simple program tailored to the TI-59 hand-held calculator uses the Darcy pressure-drop formula (modified for expressing the friction factor) to compute the unknown parameter needed to solve the fluid problem. Instead of several friction-factor equations applicable only in the individual flow regimes, the program uses a single, full-range friction-factor equation with three sets of coefficients to suit the conditions of the problem.

Verma, C.P.

1980-07-28

7

Analysis of ANS LWR physics benchmark problems.  

SciTech Connect

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

Taiwo, T. A.

1998-07-29

8

Finite Element Modeling of the World Federation's Second MFL Benchmark Problem  

NASA Astrophysics Data System (ADS)

This paper presents results obtained by simulating the second magnetic flux leakage benchmark problem proposed by the World Federation of NDE Centers. The geometry consists of notches machined on the internal and external surfaces of a rotating steel pipe that is placed between two yokes that are part of a magnetic circuit energized by an electromagnet. The model calculates the radial component of the leaked field at specific positions. The nonlinear material property of the ferromagnetic pipe is taken into account in simulating the problem. The velocity effect caused by the rotation of the pipe is, however, ignored for reasons of simplicity.

Zeng, Zhiwei; Tian, Yong; Udpa, Satish; Udpa, Lalita

2004-02-01

9

Computational evaluation of two reactor benchmark problems  

E-print Network

boron concentrations for the cores using assembly types A, B and C are given in the benchmark problem's specifications as 1511 PPM, 1335. 5 PPM and 794 PPM, respectively. The abbreviation, PPM, refers to parts per million by weight. The corresponding... atom densities are shown in Table V at the critical soluble boron concentrations for each case. TABLE V Coolant Atomic Number Densities. Nuclide Concentrations (10 atom/cm') IOB 11B lsp Core A 6. 6736E-2 1. 6719E-S 6. 7298E-S 3. 3288E-2...

Cowan, James Anthony

1998-01-01

10

PI-ping - Benchmark Tool for Testing Latencies and Throughput in Operating Systems  

NASA Astrophysics Data System (ADS)

In this paper we present a benchmark tool called PI-ping that can be used to compare real-time performance of operating systems. It uses two types of processes that are common in operating systems - interactive tasks demanding low latencies and also processes demanding high CPU utilization. Most operating systems have to perform well in both conditions and the goal is to achieve the highest throughput when keeping the latencies within a reasonable interval. PI-ping measures the latencies of an interactive process when the system is under heavy computational load. Using PI-ping benchmark tool we are able to compare different operating systems and we attest the functionality of it using two very common operating systems - Linux and FreeBSD.

Abaffy, J.; Kraj?ovi?, T.

11

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

12

MFL Benchmark Problem 2: Laboratory Measurements  

NASA Astrophysics Data System (ADS)

This experiment involves the measurement of the magnetic flux leaked from a rotating seamless steel tube with two machined notches. The signal measured is the radial component of the leaked field at a fixed point in space, as a function of the notch position, for four values of the liftoff and two notches. As the pipe tangential velocity was varied between 0.23 and 0.62 m/s, the sole observed effect was that of increasing the signal by a value that grows linearly with the velocity and is independent of the notch angular position.

Etcheverry, J.; Pignotti, A.; Sánchez, G.; Stickar, P.

2003-03-01

13

A proposed benchmark problem for cargo nuclear threat monitoring  

NASA Astrophysics Data System (ADS)

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

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

2011-10-01

14

Second Computational Aeroacoustics (CAA) Workshop on Benchmark Problems  

NASA Technical Reports Server (NTRS)

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

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

1997-01-01

15

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

16

Numerical simulation results for the eddy current benchmark problem  

NASA Astrophysics Data System (ADS)

This paper presents the numerical simulation results on an eddy current NDE benchmark problem proposed by the World Federation of NDE Centers. The problem involves the calculation of the impedance of a pair of differentially connected coils scanning an infinitely long tube. The excitation source is provided by feeding the coils with an AC current. An edge-based finite element method is used to simulate the problem numerically. Preliminary results obtained using the simulation model are presented.

Li, Y.; Zhang, Z.; Sun, Y.; Udpa, L.; Udpa, S.

2002-05-01

17

Energy Storage Benchmark Problems Daniel F. Salas1,3  

E-print Network

& Biological Engineering 2 Department of Operations Research & Financial Engineering 3 Princeton Laboratory) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 5 The Benchmarks 6 1 #12;5.1 The MATLAB Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 1 Purpose In this document, we lay out the model for a general energy storage control problem

Powell, Warren B.

18

Benchmark problems in which equality plays the major role  

SciTech Connect

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

Lusk, E.; Wos, L.

1992-01-01

19

Benchmark problems in which equality plays the major role  

SciTech Connect

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

Lusk, E.; Wos, L.

1992-05-01

20

MODEL PREDICTION RESULTS FOR 2008 ULTRASONIC BENCHMARK PROBLEMS  

SciTech Connect

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

Kim, Hak-Joon; Song, Sung-Jin [School of Mechanical Eng., Sungkyunkwan University, Suwon, 440-746 (Korea, Republic of)

2009-03-03

21

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

22

Workshops and problems for benchmarking eddy current codes  

SciTech Connect

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

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

1988-08-01

23

Comet solutions to a stylized BWR benchmark problem  

SciTech Connect

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

Zhang, D.; Rahnema, F. [Georgia Inst. of Technology, 770 State Street, Atlanta, GA 30332-0745 (United States)

2012-07-01

24

A Benchmark Problem for Development of Autonomous Structural Modal Identification  

NASA Technical Reports Server (NTRS)

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

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

1996-01-01

25

COMET solutions to whole core CANDU-6 benchmark problems  

SciTech Connect

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

Forget, B.; Rahnema, F. [Nuclear and Radiological Engineering / Medical Physics Programs, George W. Woodruff School, Georgia Inst. of Technology, Atlanta, GA 30332-0405 (United States)

2006-07-01

26

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

27

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

28

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

SciTech Connect

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

Ivanov, A.; Sanchez, V. [Karlsruhe Inst. of Technology, Inst. for Neutron Physics and Reactor Technology, Herman-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Hoogenboom, J. E. [Delft Univ. of Technology, Faculty of Applied Sciences, Mekelweg 15, 2629 JB Delft (Netherlands)

2012-07-01

29

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

30

Comparison of Numerical Schemes for a Realistic Computational Aeroacoustics Benchmark Problem  

NASA Technical Reports Server (NTRS)

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

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

2004-01-01

31

SOLUTION OF AEROACOUSTIC BENCHMARK PROBLEMS BY DISCONTINUOUS GALERKIN METHOD AND PERFECTLY  

E-print Network

SOLUTION OF AEROACOUSTIC BENCHMARK PROBLEMS BY DISCONTINUOUS GALERKIN METHOD AND PERFECTLY MATCHED are presented. For Problem 1, the one­dimensional wave equation is solved by the discontinuous Galerkin method. Numerical dispersion and dissipation er­ rors of the discontinuous Galerkin method are discussed

Hu, Fang Q.

32

SOLUTION OF AEROACOUSTIC BENCHMARK PROBLEMS BY DISCONTINUOUS GALERKIN METHOD AND PERFECTLY  

E-print Network

SOLUTION OF AEROACOUSTIC BENCHMARK PROBLEMS BY DISCONTINUOUS GALERKIN METHOD AND PERFECTLY MATCHED are presented. For Problem 1, the one-dimensional wave equation is solved by the discontinuous Galerkin method. Numerical dispersion and dissipation er- rors of the discontinuous Galerkin method are discussed

Hu, Fang Q.

33

Application of a Game Theoretic Controller to a Benchmark Problem  

Microsoft Academic Search

The game theoretic controller whose structure is idential to that of both the linear-exponential-Gaussian and H¿ controller is applied to the problem of controlling a mass-spring system which approximates the dynamics of a flexible structure. By viewing the plant parameter variation as an internal feedback loop, plant uncertainties of the system, input, and output matrices can be decomposed into a

Ihnseok Rhee; Jason L. Speyer

1990-01-01

34

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

PubMed

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

Lennartsson, Jan; Lindberg, Carl

2015-01-01

35

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

SciTech Connect

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

Kelly, D. J.; Sutton, T. M. [Knolls Atomic Power Laboratory, Bechtel Marine Propulsion Corporation, P. O. Box 1072, Schenectady, NY 12301-1072 (United States); Wilson, S. C. [Bertis Atomic Power Laboratory, Bechtel Marine Propulsion Corporation, P. O. Box 79, West Mifflin, PA 15122-0079 (United States)

2012-07-01

36

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

SciTech Connect

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

Zhang, D.; Rahnema, F. [Georgia Inst. of Technology, 770 State Street, Atlanta, GA 30332-0745 (United States)

2012-07-01

37

Foam pigs solve pipe cleaning problems offshore Brazil  

SciTech Connect

Pipeline systems in which conventional pigs cannot be run are common in such complex offshore installations as are found in Brazil`s Campos basin. These systems may contain changing pipe diameters or wet christmas trees and manifolds. A new concept for using low cost, low-density foam pigs for both liquid removal in wet-gas pipelines and paraffin removal in oil and multiphase pipelines has been successfully tested offshore Brazil. Although the present discussion focuses on condensate and paraffin removal in pipelines, the principles can be applied to several kinds of operations including general pipeline cleaning, product removal or separation in pipeline, corrosion evaluation, and chemical product application.

Lima, P.C.R.; Neto, S.J.A. [Petroleo Brasileiro S.A., Rio de Janeiro (Brazil)

1995-10-02

38

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

39

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

40

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

41

An improved transmission line matrix model for the 2D ideal wedge benchmark problem  

NASA Astrophysics Data System (ADS)

The numerical modelling of acoustic propagation in underwater environments using transmission line matrix (TLM) has received little attention for some time. This has been due, in part, to the need for an open boundary description, also known as a 'perfectly matched load' or PML, and the requirement for an accurate description of non-uniform bounding walls. The first of these problems has been solved by many researchers in subsequent years. The paper describes a novel solution to the second problem, allowing the incorporation of boundary-conforming Cartesian meshes into TLM schemes for acoustic propagation. This and a related technique are compared using the Buckingham and Tolstoy ideal 2D wedge benchmark test.

Scott, I. J. G.; de Cogan, D.

2008-04-01

42

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

43

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

44

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

SciTech Connect

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

Griffin, O. M.

1980-03-14

45

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.

46

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

NASA Technical Reports Server (NTRS)

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

Hu, Fang Q.; Manthey, Joe L.

1997-01-01

47

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

48

HySafe standard benchmark Problem SBEP-V11: Predictions of hydrogen release and dispersion from a CGH2 bus in an underpass  

Microsoft Academic Search

One of the tasks of the HySafe Network of Excellence was the evaluation of available CFD tools and models for dispersion and combustion in selected hydrogen release scenarios identified as “standard benchmark problems” (SBEPs). This paper presents the results of the HySafe standard benchmark problem SBEP-V11. The situation considered is a high pressure hydrogen jet release from a compressed gaseous

A. G. Venetsanos; E. Papanikolaou; O. R. Hansen; P. Middha; J. Garcia; M. Heitsch; D. Baraldi; P. Adams

2010-01-01

49

Fuzzy control of a benchmark problem: a computing with words approach  

Microsoft Academic Search

Abstract: The rotational\\/translational proof-mass actuator (RTAC) system is awell-known benchmark for nonlinear control for which a number ofcontrollers were designed. In this paper we apply fuzzy Lyapunovsynthesis, which is a computing with words version of classical Lyapunovsynthesis, to design fuzzy controllers for the RTAC system. Itallows us to design systematically state-feedback and output-feedbackcontrollers using only a linguistic description of the

Michael Margaliot; Gideon Langholz

2004-01-01

50

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

SciTech Connect

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

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

2012-04-11

51

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

52

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

53

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

SciTech Connect

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

Kozier, K. S. [Atomic Energy of Canada Limited, Chalk River Laboratories, Chalk River, Ont. K0J 1J0 (Canada)

2006-07-01

54

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

55

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 ...

56

The saltpool benchmark problem – numerical simulation of saltwater upconing in a porous medium  

Microsoft Academic Search

Recently, a series of laboratory experiments was carried out in which a typical variable-density flow problem in a porous medium was investigated. A stable layering of saltwater below freshwater is affected by the recharge and discharge of freshwater on the top. The experiments were conducted with 1% and 10% initial salt-mass fraction contrasts. In this paper, we define a mathematical

Klaus Johannsen; Wolfgang Kinzelbach; Sascha Oswald; Gabriel Wittum

2002-01-01

57

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

58

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

SciTech Connect

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

Black, Billy D.; Menicucci, David F.; Harrison, John (Florida Solar Energy Center)

2005-10-01

59

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

60

Introduction to pipe stress analysis  

Microsoft Academic Search

This book offers a practical approach to analytical piping design. Many approaches to design are presented that are used in engineering consulting companies but are not available in books. Engineering equations from many piping codes are used and discussed. Covers problems encountered in the determination of pipe wall thickness and span limitations, design of piping configurations and supports and connections

Kannappan

1986-01-01

61

Comparison of numerical methods for simulating strongly nonlinear and heterogeneous reactive transport problems—the MoMaS benchmark case  

Microsoft Academic Search

Although multicomponent reactive transport modeling is gaining wider application in various geoscience fields, it continues\\u000a to present significant mathematical and computational challenges. There is a need to solve and compare the solutions to complex\\u000a benchmark problems, using a variety of codes, because such intercomparisons can reveal promising numerical solution approaches\\u000a and increase confidence in the application of reactive transport codes.

Jérôme Carrayrou; Joachim Hoffmann; Peter Knabner; Serge Kräutle; Caroline de Dieuleveult; Jocelyne Erhel; Jan Van der Lee; V. Lagneau; K. Ulrich Mayer; Kerry T. B. MacQuarrie

2010-01-01

62

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

63

Inhomogeneous temperature problems inside a Li/SOCl2 cell - Homogenization by integrated heat pipes  

NASA Astrophysics Data System (ADS)

The effect of the temperature gradient on the electrical capacity of the lithium/thionyl chloride (Li/SOCl2) cells and the dependence of internal heat generation on the temperature level were investigated by studying the thermal behavior of a cell constituted by a number of couples stacken in a stainless steel cylinder during a discharge profile. It is shown that the temperature gradient between couples affected the depth of discharge, indicating that this gradient must be limited to prevent discrepancy in couple's voltage and inversion phenomenon. It was found that a cooling concept based on integrated heat pipes is effective in reducing the temperature gradient and in yielding homogeneous cell behavior in overdischarge.

Lefriec, C.; Suleiman, A.; Alexandre, A.

1992-07-01

64

The constant flow rate problem for fluids with increasing yield stress in a pipe  

NASA Astrophysics Data System (ADS)

Experiments show that the degradation effect observed during both stirring and pipelining tests of some coal-water slurries is mainly to be ascribed to the increase of the yield stress. Regardless of the particular mathematical model adopted to investigate the dynamics of these fluids, engineering applications force us to consider the problem of how long a constant flow rate can be maintained during the pipelining process. We choose a Bingham model where the yield stress is assumed to increase with the dissipated energy as in [5]. It is first shown that the constant flow rate problem is equivalent to solving a nonlinear functional equation in the unknown pressure gradient that generalizes the classical algebraic Buckingham equation for the same problem with constant rheological parameters. By means of a fixed-point argument we also prove that the functional equation has one and only one solution which is local in time. We finally find an estimate from below of the interval of the interval of existence. Numerical results are rather good and agree with those expected from the engineering point of view.

Gianni, R.; Pezza, L.; Rosso, F.

1995-11-01

65

Heat pipe investigations  

NASA Technical Reports Server (NTRS)

The OAO-C spacecraft has three circular heat pipes, each of a different internal design, located in the space between the spacecraft structural tube and the experiment tube, which are designed to isothermalize the structure. Two of the pipes are used to transport high heat loads, and the third is for low heat loads. The test problems deal with the charging of the pipes, modifications, the mobile tilt table, the position indicator, and the heat input mechanisms. The final results showed that the techniques used were adequate for thermal-vacuum testing of heat pipes.

Marshburn, J. P.

1972-01-01

66

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

SciTech Connect

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

Zhang, D.; Rahnema, F. [Georgia Inst. of Technology, 770 State Street, Atlanta, GA 30332-0745 (United States)

2012-07-01

67

Pipe Flow System Holly Guest  

E-print Network

Pipe Flow System Design Holly Guest #12;Problem · An engineer is asked to compute the flow rate of a given pipe system involving two reservoirs and to make recommendations based on the outputs on how to improve the design. · Inputs include: · Head of each reservoir · Head of the pump · Pipe Diameter using

Clement, Prabhakar

68

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

69

DRAINAGE PIPE DETECTOR  

Technology Transfer Automated Retrieval System (TEKTRAN)

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

70

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

71

NAS Parallel Benchmarks Results  

NASA Technical Reports Server (NTRS)

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

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

1995-01-01

72

Applications of Integral Benchmark Data  

SciTech Connect

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

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

2014-11-01

73

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

74

The DaCapo benchmarks: java benchmarking development and analysis  

Microsoft Academic Search

Since benchmarks drive computer science research and industry product development, which ones we use and how we evaluate them are key questions for the community. Despite complex run-time tradeoffs due to dynamic compilation and garbage collection required for Java programs, many evaluations still use methodolo-gies developed for C, C++, and Fortran. SPEC, the dominant pur-veyor of benchmarks, compounded this problem

Stephen M. Blackburn; Robin Garner; Chris Hoffmann; Asjad M. Khan; Kathryn S. Mckinley; Rotem Bentzur; Amer Diwan; Daniel Feinberg; Daniel Frampton; Samuel Z. Guyer; Martin Hirzel; Antony L. Hosking; Maria Jump; Han Bok Lee; J. Eliot B. Moss; Aashish Phansalkar; Darko Stefanovic; Thomas Vandrunen; Daniel Von Dincklage; Ben Wiedermann

2006-01-01

75

Hydrogen Piping Experience in Chevron  

E-print Network

) problem areas. Related industry work: American Petroleum Institute corrosion and materials work on high contamination presents many more problems, beyond the scope of this talk We will note a couple of specific, 2" hydrogen piping failure) 4 #12;5 Hydrogen piping experience largely from hydroprocessing plants

76

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

NASA Astrophysics Data System (ADS)

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

Atallah, Nidal Walid

77

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.

78

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

79

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

PubMed

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

Balabin, Roman M; Smirnov, Sergey V

2012-04-01

80

Doing Your Own Benchmark  

Microsoft Academic Search

2. Why Benchmark? Vendors often perform benchmark for marketing purposes. These benchmarks are usually the public ones covered in this book, although IBM usually runs its own set of proprietary benchmarks. Occasionally, vendors run internal benchmarks are run to uncover software bottlenecks that might constrain the product regardless of hardware capacity. Examples of these constraints include looking for a built-in

Tom Sawyer

1991-01-01

81

Drowning - a scientometric analysis and data acquisition of a constant global problem employing density equalizing mapping and scientometric benchmarking procedures  

PubMed Central

Background Drowning is a constant global problem which claims approximately half a million victims worldwide each year, whereas the number of near-drowning victims is considerably higher. Public health strategies to reduce the burden of death are still limited. While research activities in the subject drowning grow constantly, yet there is no scientometric evaluation of the existing literature at the present time. Methods The current study uses classical bibliometric tools and visualizing techniques such as density equalizing mapping to analyse and evaluate the scientific research in the field of drowning. The interpretation of the achieved results is also implemented in the context of the data collection of the WHO. Results All studies related to drowning and listed in the ISI-Web of Science database since 1900 were identified using the search term "drowning". Implementing bibliometric methods, a constant increase in quantitative markers such as number of publications per state, publication language or collaborations as well as qualitative markers such as citations were observed for research in the field of drowning. The combination with density equalizing mapping exposed different global patterns for research productivity and the total number of drowning deaths and drowning rates respectively. Chart techniques were used to illustrate bi- and multilateral research cooperation. Conclusions The present study provides the first scientometric approach that visualizes research activity on the subject of drowning. It can be assumed that the scientific approach to this topic will achieve even greater dimensions because of its continuing actuality. PMID:21999813

2011-01-01

82

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

83

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 ORNL’s ADVANTG) which combine benefits of multiple approaches, illustrates the need for a means of evaluating or comparing different techniques for radiation detection problems. This report presents a set of 9 benchmark problems for comparing different types of radiation transport calculations, identifying appropriate tools for classes of problems, and testing and guiding the development of new methods. The benchmarks were drawn primarily from existing or previous calculations with a preference for scenarios which include experimental data, or otherwise have results with a high level of confidence, are non-sensitive, and represent problem sets of interest to NA-22. From a technical perspective, the benchmarks were chosen to span a range of difficulty and to include gamma transport, neutron transport, or both and represent different important physical processes and a range of sensitivity to angular or energy fidelity. Following benchmark identification, existing information about geometry, measurements, and previous calculations were assembled. Monte Carlo results (MCNP decks) were reviewed or created and re-run in order to attain accurate computational times and to verify agreement with experimental data, when present. Benchmark information was then conveyed to ORNL in order to guide testing and development of hybrid calculations. The results of those ADVANTG calculations were then sent to PNNL for compilation. This is a report describing the details of the selected Benchmarks and results from various transport codes.

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

2013-09-24

84

CFD validation in OECD/NEA t-junction benchmark.  

SciTech Connect

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

Obabko, A. V.; Fischer, P. F.; Tautges, T. J.; Karabasov, S.; Goloviznin, V. M.; Zaytsev, M. A.; Chudanov, V. V.; Pervichko, V. A.; Aksenova, A. E. (Mathematics and Computer Science); (Cambridge Univ.); (Moscow Institute of Nuclar Energy Safety)

2011-08-23

85

Piping Plover  

USGS Multimedia Gallery

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

86

Piping Plover  

USGS Multimedia Gallery

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

87

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

88

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

89

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

90

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

91

Piping Analysis  

NASA Technical Reports Server (NTRS)

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

1980-01-01

92

Light pipes for LED measurements  

NASA Technical Reports Server (NTRS)

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

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

1976-01-01

93

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

94

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

95

Benchmarking for large-scale placement and beyond  

Microsoft Academic Search

Over the last five years, the large scale integrated circuit placement community achieved great strides in the understanding of placement problems, developed new high-performance algorithms, and achieved impressive empirical results. These advances have been supported by a nontrivial benchmarking infrastructure, and future achievements are set to draw on benchmarking as well. In this paper, we review motivations for benchmarking, especially

Saurabh N. Adya; Mehmet Can Yildiz; Igor L. Markov; Paul G. Villarrubia; Phiroze N. Parakh; Patrick H. Madden

2004-01-01

96

The dynamics of mercury flow in a curved pipe  

E-print Network

The dynamics of mercury flow in a curved pipe Yan Zhan Foluso LadeindeFoluso Ladeinde 11 of the problem Pi t ff t· Pipe curvature effect · Laminar flow in the mercury supply pipe l i· Conclusion #12 Project. · Target delivery systems involves pipe curvature, axially- d d t di l di t d l l th tdependent

McDonald, Kirk

97

Benchmarking and Data Analysis  

E-print Network

Benchmarking and Data Analysis Kellie Williams | Houston ISD ESL-KT-14-11-14 CATEE 2014: Clean Air Through Efficiency Conference, Dallas, Texas Nov. 18-20 Benchmarking ? Process of comparing data sets ? Baselines, Goals, KPIs ? Energy Star...

Williams, K.

2014-01-01

98

Whistling of a pipe system with multiple side branches: Comparison with corrugated pipes  

Microsoft Academic Search

Corrugated pipes are widely used because they combine local rigidity with global flexibility. Whistling induced by flow through such pipes can lead to serious environmental and structural problems. The whistling of a multiple side branch system is compared to the whistling behavior of corrugated pipes. The study has been restricted to cavities with sharp edges which are convenient for theoretical

D. Tonon; B. J. T. Landry; S. P. C. Belfroid; J. F. H. Willems; G. C. J. Hofmans; A. Hirschberg

2010-01-01

99

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

100

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.

101

Heat Pipes  

NASA Technical Reports Server (NTRS)

Heat Pipes were originally developed by NASA and the Los Alamos Scientific Laboratory during the 1960s to dissipate excessive heat build- up in critical areas of spacecraft and maintain even temperatures of satellites. Heat pipes are tubular devices where a working fluid alternately evaporates and condenses, transferring heat from one region of the tube to another. KONA Corporation refined and applied the same technology to solve complex heating requirements of hot runner systems in injection molds. KONA Hot Runner Systems are used throughout the plastics industry for products ranging in size from tiny medical devices to large single cavity automobile bumpers and instrument panels.

1996-01-01

102

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

103

RELAP5 Water Hammer Benchmarking via a Theta-Implicit  

E-print Network

RELAP5 Water Hammer Benchmarking via a Theta-Implicit Finite Element Algorithm Stuart Walker UT CFD for many accident based transients Course Topics · RELAP5 heat transfer in a single HFIR channel with HEU to potential energy in a closed fluid system · Pressure surges in piping systems can lead to component failure

Tennessee, University of

104

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.

Environmental Science Workshop

2011-01-01

105

Pipe connector  

Microsoft Academic Search

A safety test facility for testing sodium-cooled nuclear reactor components includes a reactor vessel and a heat exchanger submerged in sodium in the tank. The reactor vessel and heat exchanger are connected by an expansion\\/deflection pipe coupling comprising a pair of coaxially and slidably engaged tubular elements having radially enlarged opposed end portions of which at least a part is

Thomas E. Sullivan; John A. Pardini

1978-01-01

106

A performance benchmark test for geodynamo simulations  

NASA Astrophysics Data System (ADS)

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

Matsui, H.; Heien, E. M.

2013-12-01

107

Development of a magnetic coating for gas pipe detection. Final report, May 1987June 1988  

Microsoft Academic Search

The inability to accurately locate plastic gas pipe after it is buried has been a troublesome problem since plastic pipe began being used for natural gas distribution. Electromagnetic pipe locaters have been available to the gas industry for decades. However, this technology cannot locate plastic pipe without the use of a metallic wire or tape buried with the pipe. To

1989-01-01

108

Electrohydrodynamic heat pipe research  

NASA Technical Reports Server (NTRS)

Experimental and theoretical applications to electrohydrodynamic heat pipe (EHDHP) research are presented. Two problems in the research which are discussed are the prediction of the effective thermal conductance of an EHDHP with threaded grooves for fluid distribution to the evaporator of an EHDHP. Hydrodynamic equations are included along with a discussion of boundary conditions and burn-out conditions. A discussion of the theoretical and experimental results is presented.

Jones, T. B.; Perry, M. P.

1973-01-01

109

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

110

Mixed-Oxide (MOX) Fuel Performance Benchmarks  

SciTech Connect

Within the framework of the OECD/NEA Expert Group on Reactor-based Plutonium disposition (TFRPD), a fuel modeling code benchmarks for MOX fuel was initiated. This paper summarizes the calculation results provided by the contributors for the first two fuel performance benchmark problems. A limited sensitivity study of the effect of the rod power uncertainty on code predictions of fuel centerline temperature and fuel pin pressure also was performed and is included in the paper.

Ott, Larry J [ORNL; Tverberg, Terje [OECD Halden Reactor Project; Sartori, Enrico [ORNL

2009-01-01

111

NASTRAN analysis of an air storage piping system  

NASA Technical Reports Server (NTRS)

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

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

1973-01-01

112

The oo7 Benchmark  

Microsoft Academic Search

The OO7 Benchmark represents a comprehensive test of OODBMS performance. In thisreport we describe the benchmark and present performance results from its implementationin four OODB systems. It is our hope that the OO7 Benchmark will provide useful insightfor end-users evaluating the performance of OODB systems# we also hope that the researchcommunity will find that OO7 provides a database schema, instance,

Michael J. Carey; David J. Dewitt; Jeffrey F. Naughton

1993-01-01

113

The 007 Benchmark  

Microsoft Academic Search

The OO7 Benchmark represents a comprehensive test of OODBMS performance. In this paper we describe the benchmark and present performance results from its implementation in three OODBMS systems. It is our hope that the OO7 Benchmark will provide useful insight for end-users evaluating the performance of OODBMS systems; we also hope that the research community will find that OO7 provides

Michael J. Carey; David J. DeWitt; Jeffrey F. Naughton

1993-01-01

114

MCNP neutron benchmarks  

Microsoft Academic Search

More than 50 neutron benchmark calculations have recently been completed as part of an ongoing program to validate the MCNP Monte Carlo radiation transport code. The benchmark calculations reported here are part of an ongoing multiyear, multiperson effort to benchmark version 4 of the MCNP code. The MCNP is a Monte Carlo three-dimensional general-purpose, continuous-energy neutron, photon, and electron transport

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

1992-01-01

115

Buried pipe design  

Microsoft Academic Search

This book covers basic information on proper, cost-effective design of buried-pipe systems for underground fluid transportation. Examines various pipe products available. Discusses soil engineering and piping mechanics. Specific topics include pipe-wall stresses and strains; design bases; rigid- and flexible-pipe analysis; soil pressure; and longitudinal, wheel, expansive-soil, and frost loading.

Mosler

1990-01-01

116

Design and off design pipe network geothermal power plant analysis with power pipe simulator  

Microsoft Academic Search

One of the biggest problems when analysing pipe network behaviour is the difficulty in accounting for the actual components features, as some conditions change in relation to the designed one. This problem occurs, for example, when some power machines, like turbines or pumps, are connected to the pipes. In fact, for these devices, one flow rate value corresponds to each

Francesco Di Maria

2000-01-01

117

New NAS Parallel Benchmarks Results  

NASA Technical Reports Server (NTRS)

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

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

1997-01-01

118

USGS Yosemite Benchmark Streamgage  

USGS Multimedia Gallery

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

119

BENCHMARK DOSE SOFTWARE (BMDS)  

EPA Science Inventory

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

120

Thermal Performance Benchmarking (Presentation)  

SciTech Connect

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

Moreno, G.

2014-11-01

121

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

122

Verification and validation benchmarks.  

SciTech Connect

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

Oberkampf, William Louis; Trucano, Timothy Guy

2007-02-01

123

The feasibility of electrohydrodynamic heat pipes  

NASA Technical Reports Server (NTRS)

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

Jones, T. B.

1971-01-01

124

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

125

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

126

On the Radiation of Sound from an Unflanged Circular Pipe  

Microsoft Academic Search

A rigorous and explicit solution is obtained for the problem of sound radiation from an unflanged circular pipe, assuming axially symmetric excitation. The solution is valid throughout the wave-length range of dominant mode (plane wave) propagation in the pipe. The reflection coefficient for the velocity potential within the pipe and the power-gain function, embodying the characteristics of the radiation pattern,

Harold Levine; Julian Schwinger

1948-01-01

127

Computation of flow-induced vibrations in piping systems  

Microsoft Academic Search

Local pressure fluctuations and associated acoustic sources in piping systems are experimentally characterized for several current singularities. Attention is then given to the response problem of piping system to such sources: a theoretical formulation for the modal characteristics and transfer function computation of piping systems conveying fluid is presented. The results of an experimental test are compared with the TEDEL

R. J. Gibert

1980-01-01

128

Toxicological Benchmarks for Wildlife  

SciTech Connect

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

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

1993-01-01

129

Translational benchmark risk analysis  

PubMed Central

Translational development – in the sense of translating a mature methodology from one area of application to another, evolving area – is discussed for the use of benchmark doses in quantitative risk assessment. Illustrations are presented with traditional applications of the benchmark paradigm in biology and toxicology, and also with risk endpoints that differ from traditional toxicological archetypes. It is seen that the benchmark approach can apply to a diverse spectrum of risk management settings. This suggests a promising future for this important risk-analytic tool. Extensions of the method to a wider variety of applications represent a significant opportunity for enhancing environmental, biomedical, industrial, and socio-economic risk assessments. PMID:20953283

Piegorsch, Walter W.

2010-01-01

130

Rehabilitating underground pipes  

SciTech Connect

Nearly 500,000 miles of industrial pipeline in the US are almost three times older than their expected usefulness. And aging pipes that are improperly maintained can cause a variety of environmental problems. It is essential for facilities to have a system of planned maintenance procedures to prevent structural failures related to inflow/infiltration and exfiltration. Trenchless repair methods, often referred to as pipeline rehabilitation, require the plant engineer to consider a range of activities, including demand projection, system performance assessment, investigation, evaluation of defects and deficiencies, remedial options, and implementation. Two methods of pipeline rehabilitation, slip lining and cured-in-place, are described.

Sorrell, P. [Insituform Technologies, Inc., Memphis, TN (United States)

1995-06-05

131

The effect of white or grey PVC pipe and its joint solvents (primer and cement) on odour problems in drinking water distribution systems.  

PubMed

A study of the production of odour-causing compounds was conducted from the leaching of polyvinylchloride (PVC) pipe and its joints, primer and cement, into drinking water distribution systems. Flavour Profile Analysis (FPA), closed-loop stripping analysis--gas chromatography/mass spectrometry (CLSA-GC/MS) and sensory-GC analysis of white or grey PVC alone found no odour-causing compounds produced during the leaching experiments. FPA analysis of the PVC's primer and cement leached alone and/or when applied to grey or white PVC pipes produced a glue/varnish odour. A sweet/phenolic odour replaced the glue/varnish odour after the leached media were diluted with Milli-Q water to threshold odour intensity. Three compounds were responsible for the sweet/phenolic odour and were observed by sensoryGC analysis. The leaching study of the PVC pipe with its joint solvents (primer and cement) concluded that the original solvent compounds, and their reaction products that formed during the bonding process on the PVC pipe, were a primary source of the glue/varnish odour. The original compounds of the PVC primer and cement were not detected by CLSA-GC/MS, due to their high volatility during the CLSA extraction method and/or these compounds appeared in a solvent peak of the GC/MS analysis. However, the original primer and cement chemicals (acetone, tetrahydrofuran, methyl ethyl ketone, and cyclohexanone) had a glue/varnish odour. A total of nine odorous GC peaks were produced as reaction products from leaching of primer in water and white or grey PVC pipe with primer and cement, and white or grey PVC with primer only. None of these compounds were among the chemical ingredients in the original primer or cement. Four GC peaks with a sweet/phenolic odour were present due to the reaction products of the cement leached with white or grey PVC. None of these compounds were positively identified. PMID:17489407

Wiesenthal, K E; Suffet, I H

2007-01-01

132

Ultrasonic pipe assessment  

DOEpatents

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

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

2003-12-23

133

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

134

Benchmarking TENDL-2012  

NASA Astrophysics Data System (ADS)

The new release of the TENDL nuclear data library, TENDL-2012, was tested by performing many benchmark calculations. Close to 2000 criticality safety benchmark cases were used, as well as many benchmark shielding cases. All the runs could be compared with similar runs based on the nuclear data libraries ENDF/B-VII.1, JENDL-4.0, and JEFF-3.1.1 respectively. The results are that many of the criticality safety results obtained with TENDL-2012 are close to the ones for the other libraries. In particular the results for the thermal spectrum cases with LEU fuel are good. Nevertheless, there is a fair amount of cases for which the TENDL-2012 results are not as good as the other libraries. Especially a number of fast spectrum cases with reflectors are not well described. The results for the shielding benchmarks are mostly similar to the ones for the other libraries. Some isolated cases with differences are identified.

van der Marck, S. C.; Koning, A. J.; Rochman, D. A.

2014-04-01

135

The KMAT: Benchmarking Knowledge Management.  

ERIC Educational Resources Information Center

Provides an overview of knowledge management and benchmarking, including the benefits and methods of benchmarking (e.g., competitive, cooperative, collaborative, and internal benchmarking). Arthur Andersen's KMAT (Knowledge Management Assessment Tool) is described. The KMAT is a collaborative benchmarking tool, designed to help organizations make…

de Jager, Martha

136

Toxicological Benchmarks for Wildlife  

Microsoft Academic Search

Ecological risks of environmental contaminants are evaluated by using a two-tiered process. In the first tier, a screening assessment is performed where concentrations of contaminants in the environment are compared to no observed adverse effects level (NOAEL)-based toxicological benchmarks. These benchmarks represent concentrations of chemicals (i.e., concentrations presumed to be nonhazardous to the biota) in environmental media (water, sediment, soil,

B. E. Opresko; D. M. Suter

1993-01-01

137

Organ pipe resonance induced vibration in piping system  

SciTech Connect

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

Wang, T.

1996-12-01

138

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

139

Pipe crawlers: Versatile adaptations for real applications  

SciTech Connect

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

Hapstack, M.; Talarek, T.R.

1990-01-01

140

Real-time full signature corrosion detection of underground casing pipes  

Microsoft Academic Search

Steel casing pipes used in underground gas storage or in oil fields are subjected to corrosion. Corrosion frequently causes some pitting or wall thinning to the internal or external of casing pipes. More serious corrosion would form holes on the casing pipes and induce serious operational problems. Hence, corrosion monitoring and early detection of field oil pipe is considerably important

Jiming Yin; J. Pineda de Gyvez; Mi Lu

1996-01-01

141

Flexible ocean upwelling pipe  

SciTech Connect

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

Person, Abraham (Los Alamitos, CA)

1980-01-01

142

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

143

Using Flexible Pipe (poly-pipe) with Surface Irrigation  

E-print Network

Aimed at farmers and irrigators who want to irrigate their crops using flexible plastic pipes (commonly called "poly-pipe), this publication highlights (1) advantages of using poly-pipe, (2) factors to consider in selecting such pipe, and (3...

Peries, Xavier; Enciso, Juan

2005-10-05

144

INTERIOR VIEW WITH PIPE CASTING MACHINE CASTING A 24' PIPE ...  

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

INTERIOR VIEW WITH PIPE CASTING MACHINE CASTING A 24' PIPE AND OPERATOR JOHNNY NIXON. - United States Pipe & Foundry Company Plant, Pipe Casting & Testing Area, 2023 St. Louis Avenue at I-20/59, Bessemer, Jefferson County, AL

145

INTERIOR VIEW WITH PIPE CASTING MACHINE EXTRUDING A 24' PIPE ...  

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

INTERIOR VIEW WITH PIPE CASTING MACHINE EXTRUDING A 24' PIPE AND OPERATOR JOHNNY NIXON. - United States Pipe & Foundry Company Plant, Pipe Casting & Testing Area, 2023 St. Louis Avenue at I-20/59, Bessemer, Jefferson County, AL

146

COVE 2A benchmarking calculations using LLUVIA  

SciTech Connect

Benchmarking calculations using the code LLUVIA have been performed in support of the code verification activity (COVE 2A) for the Yucca Mountain Project (YMP). LLUVIA is a program designed for the efficient solution of one-dimensional, steady flow through multiple layers of saturated or partially saturated, fractured, porous media. The benchmarking calculations involve six steady-state and six time-dependent infiltration problems. For the time-dependent analyses, LLUVIA reported only the final steady-state results. This report documents preliminary calculations, resulting code modifications and final calculations for the COVE 2A study. 7 refs., 79 figs., 3 tabs.

Hopkins, P.L.

1990-07-01

147

Benchmarking the solar dynamo with Maxima  

E-print Network

Recently, Jouve et al(A&A, 2008) published the paper that presents the numerical benchmark for the solar dynamo models. Here, I would like to show a way how to get it with help of computer algebra system Maxima. This way was used in our paper (Pipin & Seehafer, A&A 2008, in print) to test some new ideas in the large-scale stellar dynamos. In the present paper I complement the dynamo benchmark with the standard test that address the problem of the free-decay modes in the sphere which is submerged in vacuum.

Pipin, Valery V

2008-01-01

148

Reusable pipe flange covers  

DOEpatents

A molded, flexible pipe flange cover for temporarily covering a pipe flange and a pipe opening includes a substantially round center portion having a peripheral skirt portion depending from the center portion, the center portion adapted to engage a front side of the pipe flange and to seal the pipe opening. The peripheral skirt portion is formed to include a plurality of circumferentially spaced tabs, wherein free ends of the flexible tabs are formed with respective through passages adapted to receive a drawstring for pulling the tabs together on a back side of the pipe flange.

Holden, James Elliott (Simpsonville, SC); Perez, Julieta (Houston, TX)

2001-01-01

149

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, João Marcos; Camerini, Cesar; Rocha, João Vicente; Areiza, Maria Cristina

2013-01-01

150

Accelerated randomized benchmarking  

NASA Astrophysics Data System (ADS)

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.

Granade, Christopher; Ferrie, Christopher; Cory, D. G.

2015-01-01

151

Benchmarking Pthreads performance  

SciTech Connect

The importance of the performance of threads libraries is growing as clusters of shared memory machines become more popular POSIX threads, or Pthreads, is an industry threads library standard. We have implemented the first Pthreads benchmark suite. In addition to measuring basic thread functions, such as thread creation, we apply the L.ogP model to standard Pthreads communication mechanisms. We present the results of our tests for several hardware platforms. These results demonstrate that the performance of existing Pthreads implementations varies widely; parts of nearly all of these implementations could be further optimized. Since hardware differences do not fully explain these performance variations, optimizations could improve the implementations. 2. Incorporating Threads Benchmarks into SKaMPI is an MPI benchmark suite that provides a general framework for performance analysis [7]. SKaMPI does not exhaustively test the MPI standard. Instead, it

May, J M; de Supinski, B R

1999-04-27

152

The FTIO Benchmark  

NASA Technical Reports Server (NTRS)

We introduce a new benchmark for measuring the performance of parallel input/ouput. This benchmark has flexible initialization. size. and scaling properties that allows it to satisfy seven criteria for practical parallel I/O benchmarks. We obtained performance results while running on the a SGI Origin2OOO computer with various numbers of processors: with 4 processors. the performance was 68.9 Mflop/s with 0.52 of the time spent on I/O, with 8 processors the performance was 139.3 Mflop/s with 0.50 of the time spent on I/O, with 16 processors the performance was 173.6 Mflop/s with 0.43 of the time spent on I/O. and with 32 processors the performance was 259.1 Mflop/s with 0.47 of the time spent on I/O.

Fagerstrom, Frederick C.; Kuszmaul, Christopher L.; Woo, Alex C. (Technical Monitor)

1999-01-01

153

Pipe selection guide  

SciTech Connect

Four parameters are used to define a particular pipe: inside diameter, wall thickness, material, and ends. The factors influencing pipe selection are limited to fluid pressure, temperature, chemistry, flow rate, and cost. Other pipe parameters and factors that influence pipe selection and design are mentioned, and, where appropriate, the user is warned that at some stage in the project these factors must be dealt with. It is assumed that the objective is the direct application of geothermal water at temperatures lower than 200/sup 0/F and with 12-in. or smaller pipe. When considering friction losses for sizing purposes, only straight pipe is considered. A discussion of the characteristics and attributes of readily available pipe is included to aid in making a preliminary selection. Energy loss from buried pipe is considered.

Sanders, R.D.

1982-04-01

154

Heat pipe flight experiments  

NASA Technical Reports Server (NTRS)

OAO 3 heat pipe flight experiments to check out weightlessness behavior are reported. Tested were a hollow channel screen system with helical grooves, a heat pipe with a wicking system of horizontal grooves, and a spiral artery pipe with multichannel fluid return to the evaporator. Flight experiment data proved that all heat pipe geometries containing wicking systems provided uninterrupted fluid return to the condensators during weightlessness and sufficient cooling for isothermalizing optical instruments onboard OAO.

Ollendorf, S.

1973-01-01

155

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

156

Benchmarking: graphics workstations  

SciTech Connect

This paper reports on work being performed to benchmark a new breed of machines, the graphics workstations for scientific and engineering applications. We begin with the history of workstations and how they developed. Many different forces created the graphics workstation. Scientific and engineering calculations are traditionally performed by super computers in a computing center. The graphic workstation was introduced, and this technology was added to the computing environment. The answers we need are ... what can the workstations do and when do we remove the programs or parts of programs from supercomputers and place them on worstations. Benchmarks and what they can and cannot measure are discussed in this light. The particulars about graphics benchmarks and the operating system, including windows, are reviewed, then the benchmarks we are using are described and the results are presented. Since this work is never finished, future plans are also discussed. The emphasis of our work is toward scientific and engineering workstations connected with existing mainframe computers. In the industry today we hear the term JAWS (Just Another WorkStation) when a new workstation is introduced. What does the new product do beyond those on the market. In this paper we present ways to measure and tell the difference between workstations.

Brown, B.E.; Judd, R.L.

1985-09-11

157

Bryce Canyon Benchmark  

USGS Multimedia Gallery

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

158

Benchmark Comparisons August 2006  

E-print Network

administered oversamples are not included. Mean The mean is the weighted arithmetic average of student level Comparisons Report Class Mean a Sig b Effect Size c Mean a Sig b Effect Size c Mean a Sig b Effect Size c Benchmark Mean Comparisons NSSE 2006 51.9 NSSEville State compared with: 54.3 Mean a NSSEville State Level

Rainforth, Emma C.

159

Benchmarking for maximum value.  

PubMed

Speaking at the most recent Healthcare Estates conference, Ed Baldwin, of international built asset consultancy EC Harris LLP, examined the role of benchmarking and market-testing--two of the key methods used to evaluate the quality and cost-effectiveness of hard and soft FM services provided under PFI healthcare schemes to ensure they are offering maximum value for money. PMID:19344004

Baldwin, Ed

2009-03-01

160

Benchmark Comparisons August 2011  

E-print Network

Carnegie Class NSSE 2011 M ean a 54.4 58.6 a We ighted by ge nder and enro llm ent s tatus (a nd by ins divided by the po o led s tandard deviatio n. Distributions of Student Benchmark Scores No te: Each bo x

161

Benchmark Comparisons August 2010  

E-print Network

expectations for student performance. M ean a 52.8 57.2 a We ighted by ge nde r and enro llm ent s ta tus (plus renc e divide d by the po o led s tandard deviatio n. Distributions of Student Benchmark Scores Level

162

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

163

Diffusion of pipe jets  

Microsoft Academic Search

This paper presents fundamental research work on jet dissipation in pipes and closed chambers in order to study the details of flow pattern, velocity distribution, and energy reduction. The effects of chamber dimensions and jet heights are also investigated. Experiments were carried out with air and water jets being discharged into a pipe. The ratio of pipe to nozzle diameter

S. K. Al-Naib; R. Vasanthakumaran

1993-01-01

164

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

165

NAS Parallel Benchmarks Results 3-95  

NASA Technical Reports Server (NTRS)

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

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

1995-01-01

166

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

167

Quantum Benchmarks for Pure Single-Mode Gaussian States  

NASA Astrophysics Data System (ADS)

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

Chiribella, Giulio; Adesso, Gerardo

2014-01-01

168

Automating the task of tracking the delivery and receipt of fabricated pipe spools in industrial projects  

Microsoft Academic Search

Piping in industrial projects is a critical and costly process as thousands of unique pipe spools go through design, fabrication, interim processing, delivery, storage, installation and inspection. Current methods for tracking pipe spools through this long supply chain are subject to many problems. This paper evaluates the use of RFID technology as a possible solution to some of these problems

Jongchul Song; Carl T. Haas; Carlos Caldas; Esin Ergen; Burcu Akinci

2006-01-01

169

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

170

Benchmarking Corporate Energy Management  

E-print Network

's energy management procedures and perfonnance compare to that of other companies. Energy management involves everything from setting goals and targets to implementing best maintenance practices. This paper, however, discusses benchmarking energy... co-authored by me for the IETC 2000 titled "Corporate Energy Management: A Survey of Large Manufacturing Companies," eight elements of best energy management practice were presented and data on the energy management practices of 23 companies...

Norland, D. L.

171

Benchmark Comparisons August 2006  

E-print Network

administered oversamples are not included. Mean The mean is the weighted arithmetic average of student level Report Class Mean a Sig b Effect Size c Mean a Sig b Effect Size c Mean a Sig b Effect Size c First-Year 53.0 51.6 52.6 Seniors 57.5 56.0 56.5 Level of Academic Challenge (LAC) Selected Peers Benchmark Mean

Haykin, Simon

172

Benchmarking ordering techniques for nonserial dynamic programming  

E-print Network

Five ordering algorithms for the nonserial dynamic programming algorithm for solving sparse discrete optimization problems are compared in this paper. The benchmarking reveals that the ordering of the variables has a significant impact on the run-time of these algorithms. In addition, it is shown that different orderings are most effective for different classes of problems. Finally, it is shown that, amongst the algorithms considered here, heuristics based on maximum cardinality search and minimum fill-in perform best for solving the discrete optimization problems considered in this paper.

Sviridenko, Alexander

2011-01-01

173

NAS Parallel Benchmarks I/O Version 2.4. 2.4  

NASA Technical Reports Server (NTRS)

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

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

2002-01-01

174

Benchmarking Evolutionary Algorithms: Towards Exploratory Landscape Analysis  

Microsoft Academic Search

\\u000a We present methods to answer two basic questions that arise when benchmarking optimization algorithms. The first one is: which\\u000a algorithm is the ‘best’ one? and the second one: which algorithm should I use for my real world problem? Both are connected\\u000a and neither is easy to answer. We present methods which can be used to analyse the raw data of

Olaf Mersmann; Mike Preuss; Heike Trautmann

2010-01-01

175

Water and Mercury Pipe Flow Simulation in FLUENTSimulation in FLUENT  

E-print Network

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

McDonald, Kirk

176

Stress analysis of piping elbows  

SciTech Connect

The problem undertaken in this paper is the investigation of the stresses generated in circular piping elbows of variable thickness, under the influence of uniform internal pressure. It is observed now that the material region and the imposed loading conform to the same axial symmetry. This fact strongly suggests the employment of toroidal coordinates and the Boussinesq-Papkovitch-Neuber (BPN) potential function approach towards obtaining the solution to the above posed problem. The results obtained by this BPN approach are compared with the numerical solution generated by a boundary integral equation approach. The comparison yields a good agreement.

Choi, J.; Rentzepis, G.M. [Georgia Inst. of Tech., Atlanta, GA (United States). George W. Woodruff School of Mechanical Engineering

1996-12-31

177

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

178

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

179

Polyvinylchloride (PVC) pipe hazards  

SciTech Connect

PVC pipe should be used only for low pressure liquid systems where the liquid is at or near ambient temperature. PVC pipe, because of its brittle nature, should be used only in unmanned areas or where it is isolated from personnel. It should be otherwise protected so that it is not subjected to ultraviolet light, temperature cycling or damage after installation. Heat (particularly welding and cutting) should be avoided in the immediate vicinity of the piping. PVC pipe should not be used where it would be subject to vibration. The effects of certain chemicals on PVC should be carefully considered, both where the pipe is a carrying medium for the chemical and where the pipe may be exposed to the chemicals externally.

Not Available

1983-01-01

180

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

181

Pipe crawler apparatus  

DOEpatents

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

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

2002-01-01

182

External artery heat pipe  

NASA Technical Reports Server (NTRS)

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

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

1989-01-01

183

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

184

Internal pipe attachment mechanism  

DOEpatents

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

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

1994-12-13

185

Internal pipe attachment mechanism  

DOEpatents

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

Bast, Richard M. (Livermore, CA); Chesnut, Dwayne A. (Pleasanton, CA); Henning, Carl D. (Livermore, CA); Lennon, Joseph P. (Livermore, CA); Pastrnak, John W. (Livermore, CA); Smith, Joseph A. (Livermore, CA)

1994-01-01

186

Improved neural fitted Q iteration applied to a novel computer gaming and learning benchmark  

Microsoft Academic Search

Neural batch reinforcement learning (RL) algo- rithms have recently shown to be a powerful tool for model-free reinforcement learning problems. In this paper, we present a novel learning benchmark from the realm of computer games and apply a variant of a neural batch RL algorithm in the scope of this benchmark. Defining the learning problem and appropriately adjusting all relevant

Thomas Gabel; Christian Lutz; Martin Riedmiller

2011-01-01

187

Analyzing the BBOB Results by Means of Benchmarking Concepts.  

PubMed

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

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

2015-01-01

188

Landmark-based autonomous navigation in sewerage pipes  

Microsoft Academic Search

We describe a method for an autonomous mobile robot to navigate through a system of sewerage pipes. Landmarks signalling positions in the pipe system have to be detected and classified, where classification is allowed do be unreliable. Self localization is interpreted as a partially observable Markov decision problem and solved accordingly. The method is implemented and used on a prototype

Joachim Hertzberg; Frank Kirchner

1996-01-01

189

Heat pipe technology issues  

SciTech Connect

Critical high temperature, high power applications in space nuclear power designs are near the current state of the art of heat pipe technology in terms of power density, operating temperature, and lifetime. Recent heat pipe development work at Los Alamos National Laboratory has involved performance testing of typical space reactor heat pipe designs to power levels in excess of 19 kW/cm/sup 2/ axially and 300 W/cm/sup 2/ radially at temperatures in the 1400 to 1500 K range. Operation at conditions in the 10 kW/cm/sup 2/ range has been sustained for periods of up to 1000 hours without evidence of performance degradation. The effective length for heat transport in these heat pipes was from 1.0 to 1.5 M. Materials used were molybdenum alloys with lithium employed as the heat pipe operating fluid. Shorter, somewhat lower power, molybdenum heat pipes have been life tested at Los Alamos for periods of greater than 25,000 hours at 1700 K with lithium and 20,000 hours at 1500/sup 0/K with sodium. These life test demonstrations and the attendant performance limit investigations provide an experimental basis for heat pipe application in space reactor design and represent the current state-of-the-art of high temperature heat pipe technology.

Merrigan, M.A.

1984-04-01

190

Loop heat pipes  

Microsoft Academic Search

Loop heat pipes (LHPs) are two-phase heat-transfer devices with capillary pumping of a working fluid. They possess all the main advantages of conventional heat pipes, but owing to the original design and special properties of the capillary structure are capable of transferring heat efficiency for distances up to several meters at any orientation in the gravity field, or to several

Yu. F. Maydanik

2005-01-01

191

The heat pipe  

Microsoft Academic Search

The heat pipe is a device having a high thermal conductance which utilizes the transport of a vapour and rejection of latent heat to achieve efficient thermal energy transport. The theory of heat pipes is well developed. Their use in applications involving temperatures in the cryogenic regime, and with development units running as high as 2000 degrees C, shows that

P. D. Dunn; D. A. Reay

1973-01-01

192

Modulated wick heat pipe  

Microsoft Academic Search

In heat pipes, modulation of evaporator wick thickness provides extra cross-sectional area for enhanced axial capillary liquid flow and extra evaporation surface area, with only a moderate increase in wick superheat (conduction resistance). This modulated wick (periodic stacks and grooves over a thin, uniform wick) is analyzed and optimized with a prescribed, empirical wick superheat limit. A thermal-hydraulic heat pipe

G. S. Hwang; M. Kaviany; W. G. Anderson; J. Zuo

2007-01-01

193

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

194

Analysis of Rotary Bayonets and Piping  

SciTech Connect

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

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

1988-08-19

195

Extendable pipe crawler  

DOEpatents

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

Hapstack, Mark (North Augusta, SC)

1991-01-01

196

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

197

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

198

Former Yosemite Hydrologic Benchmark Streamgage  

USGS Multimedia Gallery

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

199

Creating Benchmarks for Science Education.  

ERIC Educational Resources Information Center

Project 2061 has been constructing goals for science, mathematics, and technology education since 1985, beginning with high school graduation standards (in "Science for All Americans 1989") and working toward reasonable standards for students at earlier grade levels. Projected "Benchmarks for Science Literacy" will include benchmark lists, some…

Ahlgren, Andrew

1993-01-01

200

AOAB -- Automated Optimization Algorithm Benchmarking  

Microsoft Academic Search

In this paper we present AOAB, the Automated Optimization Algorithm Benchmarking system. AOAB can be used to automatically conduct experiments with numerical optimization algorithms by applying them to different benchmarks with different parameter settings. Based on the results, AOAB can automatically perform comparisons between different algorithms and settings. It can aid the researcher to identify trends for good parameter settings

Thomas Weise; Li Niu; Ke Tang

2010-01-01

201

Benchmarking. A Guide for Educators.  

ERIC Educational Resources Information Center

This book offers strategies for enhancing a school's teaching and learning by using benchmarking, a team-research and data-driven process for increasing school effectiveness. Benchmarking enables professionals to study and know their systems and continually improve their practices. The book is designed to lead a team step by step through the…

Tucker, Sue

202

The application of radiotracers in the leak detection of underground pipes  

Microsoft Academic Search

Leaks in chemical processing plants can be both expensive and dangerous. Leakage into the subsoil from underground pipes may cause environmental problems, but it is very difficult to locate the leak area in underground pipes. The development of radioactive techniques has greatly facilitated the detection of underground pipe leakages. The use of radioactive tracers affords an extremely sensitive means of

Yungchien Tong; Showen Chung

1992-01-01

203

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

204

Benchmarking monthly homogenization algorithms  

NASA Astrophysics Data System (ADS)

The COST (European Cooperation in Science and Technology) Action ES0601: Advances in homogenization methods of climate series: an integrated approach (HOME) has executed a blind intercomparison and validation study for monthly homogenization algorithms. Time series of monthly temperature and precipitation were evaluated because of their importance for climate studies and because they represent two important types of statistics (additive and multiplicative). The algorithms were validated against a realistic benchmark dataset. The benchmark contains real inhomogeneous data as well as simulated data with inserted inhomogeneities. Random break-type inhomogeneities were added to the simulated datasets modeled as a Poisson process with normally distributed breakpoint sizes. To approximate real world conditions, breaks were introduced that occur simultaneously in multiple station series within a simulated network of station data. The simulated time series also contained outliers, missing data periods and local station trends. Further, a stochastic nonlinear global (network-wide) trend was added. Participants provided 25 separate homogenized contributions as part of the blind study as well as 22 additional solutions submitted after the details of the imposed inhomogeneities were revealed. These homogenized datasets were assessed by a number of performance metrics including (i) the centered root mean square error relative to the true homogeneous value at various averaging scales, (ii) the error in linear trend estimates and (iii) traditional contingency skill scores. The metrics were computed both using the individual station series as well as the network average regional series. The performance of the contributions depends significantly on the error metric considered. Contingency scores by themselves are not very informative. Although relative homogenization algorithms typically improve the homogeneity of temperature data, only the best ones improve precipitation data. Training was found to be very important. Moreover, state-of-the-art relative homogenization algorithms developed to work with an inhomogeneous reference are shown to perform best. The study showed that currently automatic algorithms can perform as well as manual ones.

Venema, V. K. C.; Mestre, O.; Aguilar, E.; Auer, I.; Guijarro, J. A.; Domonkos, P.; Vertacnik, G.; Szentimrey, T.; Stepanek, P.; Zahradnicek, P.; Viarre, J.; Müller-Westermeier, G.; Lakatos, M.; Williams, C. N.; Menne, M.; Lindau, R.; Rasol, D.; Rustemeier, E.; Kolokythas, K.; Marinova, T.; Andresen, L.; Acquaotta, F.; Fratianni, S.; Cheval, S.; Klancar, M.; Brunetti, M.; Gruber, C.; Prohom Duran, M.; Likso, T.; Esteban, P.; Brandsma, T.

2011-08-01

205

Benchmarking foreign electronics technologies  

SciTech Connect

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

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

1994-12-01

206

Seismic pipe support construction practices  

SciTech Connect

During the mid 1970's the regulatory agencies controlling the design and construction of nuclear power plants began to demand stricter adherence to already existing codes and standards in addition to evoking new requirements. This increased scrutiny in addition to the advent of the NF subsection of the ASME code brought pipe hangers into the spotlight of nuclear plant design and construction. What before had been a minor item of low visibility became a monster causing plant delays and cost overruns. This document details some of the problems, their origins, and suggestions to reduce their impact.

Brothers, T.M.; Rudolphi, M.U.

1985-01-01

207

PIPE LEAKAGE - FUTURE CHALLENGES AND SOLUTIONS  

Microsoft Academic Search

Pipe leakage in Australia is perceived to be a major problem by many water authorities, both from an environmental point of view, as well as the associated costs that are incurred due to overdesign of our sewerage systems (to cope with wet weather loads) and the treatment of additional potable water that is lost due to leakage. This paper discusses

Stewart Burn; Dhammika DeSilva; Matthias Eiswirth; Osama Hunaidi; Andrew Speers; Julian Thornton

1999-01-01

208

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

209

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

210

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

211

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

212

Friction loss in piping  

SciTech Connect

This program for the HP-41C with one memory module computes pipe friction loss, velocity, and optimum diameter given pipe ID, flow rate, viscosity and density. Flow can be entered as 1.lb/h, 2.BPH-/sup 0/API, 3. gas mol. wt.-scfh, or 4. gpm-sp.gr. Density can be entered as 1.lb/ft, 2. mol. wt.-psig-/sup 0/F, or 3. /sup 0/API-/sup 0/F. For some standard strength pipes, nominal to actual diameter conversion is provided. A change in gas density with pressure can be taken into account if desired.

Patel, V.K.

1984-01-01

213

Benchmarking in academic pharmacy departments.  

PubMed

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

Bosso, John A; Chisholm-Burns, Marie; Nappi, Jean; Gubbins, Paul O; Ross, Leigh Ann

2010-10-11

214

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

215

A Heterogeneous Medium Analytical Benchmark  

SciTech Connect

A benchmark, called benchmark BLUE, has been developed for one-group neutral particle (neutron or photon) transport in a one-dimensional sub-critical heterogeneous plane parallel medium with surface illumination. General anisotropic scattering is accommodated through the Green's Function Method (GFM). Numerical Fourier transform inversion is used to generate the required Green's functions which are kernels to coupled integral equations that give the exiting angular fluxes. The interior scalar flux is then obtained through quadrature. A compound iterative procedure for quadrature order and slab surface source convergence provides highly accurate benchmark qualities (4- to 5- places of accuracy) results.

Ganapol, B.D.

1999-09-27

216

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

217

Heat Pipe Systems  

NASA Technical Reports Server (NTRS)

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

1993-01-01

218

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

219

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

220

Simplified pipe gun  

NASA Astrophysics Data System (ADS)

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

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

1987-12-01

221

Freezable heat pipe  

DOEpatents

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

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

1981-02-03

222

Virtual machine performance benchmarking.  

PubMed

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

Langer, Steve G; French, Todd

2011-10-01

223

Calculator programs for pipe stress engineering  

SciTech Connect

This book contains a collection of programs for solving a wide variety of stress problems using both the TI-59 and HP-41CV calculators. Each program is prefaced with a description of the problem to be solved, nomenclature, code restrictions and program limitations. Solutions are explained analytically and then followed by the complete program listing, documentation and checklists. Topics include calculations for pipewall thickness, pressure vessel analysis, reinforcement pads, allowable span, vibration, stress, and two-anchor piping systems.

Morgan, K.S.

1985-01-01

224

Pipe flow of highly concentrated sludge.  

PubMed

Industries that pump sludges experience pressure to operate at higher concentrations with sludges that have high mechanical strength properties. The viscous character of the sludge becomes increasingly non-Newtonian and yield stress in nature. The two principal problems are regime determination and laminar flow settling, which ultimately results in pipe blockage. In facing the diversities that sludge management currently presents, it is important to resolve these issues and develop solutions for engineering practice. The approaches developed at the Flow Process Research Centre to deal with these problems are introduced. The objectives of this paper are to introduce experimental data of the phenomena associated with the pipe flow of highly concentrated sludge, and use these to develop and evaluate predictive modeling approaches suitable for engineering design purposes. For the prediction of transitional flow, a new general approach for visco-plastic fluids in industrially relevant pipe sizes is presented, based on dimensional analysis of the flow problem. Settled bed behavior is modeled using an adapted two-layer model approach, in all flow regimes. The modeling approaches are evaluated using the experimental results obtained. The analysis shows that the present work provides a workable solution for the prediction of the pipe flow of highly concentrated sludges, for engineering design purposes. PMID:18821237

Slatter, Paul

2008-11-01

225

Outlook for Industrial Energy Benchmarking  

E-print Network

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

Hartley, Z.

226

NHT-1 I/O Benchmarks  

NASA Technical Reports Server (NTRS)

The NHT-1 benchmarks am a set of three scalable I/0 benchmarks suitable for evaluating the I/0 subsystems of high performance distributed memory computer systems. The benchmarks test application I/0, maximum sustained disk I/0, and maximum sustained network I/0. Sample codes are available which implement the benchmarks.

Carter, Russell; Ciotti, Bob; Fineberg, Sam; Nitzbert, Bill

1992-01-01

227

Interpreting the Benchmark Comparisons Report  

E-print Network

are not included. Mean The mean is the weighted arithmetic average of student level benchmark scores. Bar ChartsInterpreting the Benchmark Comparisons Report Class Mean a Sig b Effect Size c Mean a Sig b Effect Size c Mean a Sig b Effect Size c First-Year 51.6 .05 50.4 * .14 51.8 .04 Senior 55.9 -.01 55.6 .02 55

Rhode Island, University of

228

GTRAN- TRANSIENT ANALYSIS OF GAS PIPING SYSTEMS  

NASA Technical Reports Server (NTRS)

The GTRAN program was developed to solve transient, as well as steady state, problems for gas piping systems. GTRAN capabilities allow for the analysis of a variety of system configurations and components. These include: multiple pipe junctions; valves that change position with time; fixed restrictions (orifices, manual valves, filters, etc.); relief valves; constant pressure sources; and heat transfer for insulated piping and piping subjected to free or forced convection. In addition, boundary conditions can be incorporated to simulate specific components. The governing equations of GTRAN are the one-dimensional transient gas dynamic equations. The three equations for pressure, velocity, and density are reduced to numerical equations using an implicit Crank-Nicholson finite difference technique. Input to GTRAN includes a description of the piping network, the initial conditions, and any events (e.g. valve closings) occuring during the period of analysis. Output includes pressure, velocity, and density versus time. GTRAN is written in FORTRAN 77 for batch execution and has been implemented on a DEC VAX series computer. GTRAN was developed in 1983.

TROVILLION T A

1994-01-01

229

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

230

Research on computer systems benchmarking  

NASA Technical Reports Server (NTRS)

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

Smith, Alan Jay (Principal Investigator)

1996-01-01

231

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

232

Implementation of Benchmarking Transportation Logistics Practices and Future Benchmarking Organizations  

SciTech Connect

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

Thrower, A.W. [U.S. Department of Energy, Office of Civilian Radioactive Waste Management, Washington, DC (United States); Patric, J. [Booz Allen Hamilton, Washington, DC (United States); Keister, M. [Idaho National Laboratory, Idaho Falls, ID (United States)

2008-07-01

233

Characterization of pipes, drain lines, and ducts using the pipe explorer system  

SciTech Connect

As DOE dismantles its nuclear processing facilities, site managers must employ the best means of disposing or remediating hundreds of miles of potentially contaminated piping and duct work. Their interiors are difficult to access, and in many cases even the exteriors are inaccessible. Without adequate characterization, it must be assumed that the piping is contaminated, and the disposal cost of buried drain lines can be on the order of $1,200/ft and is often unnecessary as residual contamination levels often are below free release criteria. This paper describes the program to develop a solution to the problem of characterizing radioactive contamination in pipes. The technical approach and results of using the Pipe Explorer {trademark} system are presented. The heart of the system is SEA`s pressurized inverting membrane adapted to transport radiation detectors and other tools into pipes. It offers many benefits over other pipe inspection approaches. It has video and beta/gamma detection capabilities, and the need for alpha detection has been addressed through the development of the Alpha Explorer{trademark}. These systems have been used during various stages of decontamination and decommissioning of DOE sites, including the ANL CP-5 reactor D&D. Future improvements and extensions of their capabilities are discussed.

Cremer, C.D.; Kendrick, D.T.; Cramer, E.

1997-05-01

234

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

Code of Federal Regulations, 2010 CFR

...Shipping 5 2010-10-01 2010-10-01 false Piping and piping system components: Protection from movement. 154...Design, Construction and Equipment Cargo and Process Piping Systems § 154.503 Piping and piping system...

2010-10-01

235

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

Code of Federal Regulations, 2011 CFR

...Shipping 5 2011-10-01 2011-10-01 false Piping and piping system components: Protection from movement. 154...Design, Construction and Equipment Cargo and Process Piping Systems § 154.503 Piping and piping system...

2011-10-01

236

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

Code of Federal Regulations, 2012 CFR

...Shipping 5 2012-10-01 2012-10-01 false Piping and piping system components: Protection from movement. 154...Design, Construction and Equipment Cargo and Process Piping Systems § 154.503 Piping and piping system...

2012-10-01

237

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

Code of Federal Regulations, 2014 CFR

...Shipping 5 2014-10-01 2014-10-01 false Piping and piping system components: Protection from movement. 154...Design, Construction and Equipment Cargo and Process Piping Systems § 154.503 Piping and piping system...

2014-10-01

238

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

Code of Federal Regulations, 2013 CFR

...Shipping 5 2013-10-01 2013-10-01 false Piping and piping system components: Protection from movement. 154...Design, Construction and Equipment Cargo and Process Piping Systems § 154.503 Piping and piping system...

2013-10-01

239

Correlational effect size benchmarks.  

PubMed

Effect size information is essential for the scientific enterprise and plays an increasingly central role in the scientific process. We extracted 147,328 correlations and developed a hierarchical taxonomy of variables reported in Journal of Applied Psychology and Personnel Psychology from 1980 to 2010 to produce empirical effect size benchmarks at the omnibus level, for 20 common research domains, and for an even finer grained level of generality. Results indicate that the usual interpretation and classification of effect sizes as small, medium, and large bear almost no resemblance to findings in the field, because distributions of effect sizes exhibit tertile partitions at values approximately one-half to one-third those intuited by Cohen (1988). Our results offer information that can be used for research planning and design purposes, such as producing better informed non-nil hypotheses and estimating statistical power and planning sample size accordingly. We also offer information useful for understanding the relative importance of the effect sizes found in a particular study in relationship to others and which research domains have advanced more or less, given that larger effect sizes indicate a better understanding of a phenomenon. Also, our study offers information about research domains for which the investigation of moderating effects may be more fruitful and provide information that is likely to facilitate the implementation of Bayesian analysis. Finally, our study offers information that practitioners can use to evaluate the relative effectiveness of various types of interventions. (PsycINFO Database Record (c) 2015 APA, all rights reserved). PMID:25314367

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

2015-03-01

240

Sounding rocket heat pipe experiment.  

NASA Technical Reports Server (NTRS)

An experiment was conducted during October 1971 aboard a sounding rocket to observe the operation of several heat pipes in a zero gravity environment. The pipe designs which were tested included a spiral artery, a pedestal artery, and a plain groove. Two control pipes without wicking were also flown. The two artery pipes were similar to those which will be used on the OAO-C satellite, while the groove pipe was similar to that used on the ATS-F spacecraft. The results of the experiment indicate that the heat pipes operated satisfactorily during the flight which included four minutes of zero gravity.

Mcintosh, R.; Knowles, G.; Hembach, R. J.

1972-01-01

241

Wedgethread pipe connection  

DOEpatents

Several embodiments of a wedgethread pipe connection are disclosed that have improved makeup, sealing, and non-loosening characteristics. In one embodiment, an open wedgethread is disclosed that has an included angle measured in the gap between the stab flank and the load flank to be not less than zero, so as to prevent premature wedging between mating flanks before the position of full makeup is reached, as does occur between trapped wedgethreads wherein the included angle is less than zero. The invention may be used for pipe threads large or small, as a flush joint, with collars, screwed into plates or it may even be used to reversibly connect such as solid posts to base members where a wide makeup torque range is desired. This Open wedgethread, as opposed to trapped wedgethreads, provides a threaded pipe connection that: is more cost-effective; can seal high pressure gas; can provide selectively a connection strength as high as the pipe strength; assures easy makeup to the desired position of full makeup within a wide torque range; may have a torque strength as high as the pipe torque strength; is easier to manufacture; is easier to gage; and is less subject to handling damage.

Watts, John D.

2003-06-17

242

Remotely operated pipe connector  

DOEpatents

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

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

1988-01-01

243

Explosive Welding of Pipes  

NASA Astrophysics Data System (ADS)

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

Burtseva, Olga

2007-06-01

244

49 CFR 195.114 - Used pipe.  

Code of Federal Regulations, 2010 CFR

...114 Used pipe. Any used pipe installed in a pipeline system...the following: (a) The pipe must be of a known specification... (1) Buckles; (2) Cracks, grooves, gouges, dents...the specification to which the pipe was manufactured; or...

2010-10-01

245

Heat pipes and use of heat pipes in furnace exhaust  

DOEpatents

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

Polcyn, Adam D. (Pittsburgh, PA)

2010-12-28

246

Apparatus for moving a pipe inspection probe through piping  

DOEpatents

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

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

1995-01-01

247

Apparatus for moving a pipe inspection probe through piping  

DOEpatents

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

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

1995-07-18

248

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

249

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

250

Apparatus for inspecting piping  

DOEpatents

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

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

1995-03-21

251

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

252

Benchmark simulation models, quo vadis?  

PubMed

As the work of the IWA Task Group on Benchmarking of Control Strategies for wastewater treatment plants (WWTPs) is coming to an end, it is essential to disseminate the knowledge gained. For this reason, all authors of the IWA Scientific and Technical Report on benchmarking have come together to provide their insights, highlighting areas where knowledge may still be deficient and where new opportunities are emerging, and to propose potential avenues for future development and application of the general benchmarking framework and its associated tools. The paper focuses on the topics of temporal and spatial extension, process modifications within the WWTP, the realism of models, control strategy extensions and the potential for new evaluation tools within the existing benchmark system. We find that there are major opportunities for application within all of these areas, either from existing work already being done within the context of the benchmarking simulation models (BSMs) or applicable work in the wider literature. Of key importance is increasing capability, usability and transparency of the BSM package while avoiding unnecessary complexity. PMID:23823534

Jeppsson, U; Alex, J; Batstone, D J; Benedetti, L; Comas, J; Copp, J B; Corominas, L; Flores-Alsina, X; Gernaey, K V; Nopens, I; Pons, M-N; Rodríguez-Roda, I; Rosen, C; Steyer, J-P; Vanrolleghem, P A; Volcke, E I P; Vrecko, D

2013-01-01

253

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

254

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,

255

Heat transfer in pipes  

NASA Technical Reports Server (NTRS)

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

Burbach, T.

1985-01-01

256

Heat pipe cooled probe  

NASA Technical Reports Server (NTRS)

The basic heat pipe principle is employed to provide a self-contained passively cooled probe that may be placed into a high temperature environment. The probe consists of an evaporator region of a heat pipe and a sensing instrument. Heat is absorbed as the working fluid evaporates in the probe. The vapor is transported to the vapor space of the condenser region. Heat is dissipated from the condenser region and fins causing condensation of the working fluid, which returns to the probe by gravity and the capillary action of the wick. Working fluid, wick and condenser configurations and structure materials can be selected to maintain the probe within an acceptable temperature range.

Camarda, C. J. (inventor); Couch, L. M.

1984-01-01

257

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

258

Piping-System Solutions Using Mathcad  

E-print Network

Piping-System Solutions Using Mathcad B. K. HODGE,1 ROBERT P. TAYLOR2 1 Mechanical Engineering associated with piping systems. Examples include series piping systems, parallel piping systems, and pipingScience (www.interscience.wiley.com.); DOI 10.1002/cae.10010 Keywords: piping systems; Mathcad, Hardy

Kostic, Milivoje M.

259

Benchmarking of finite element codes for radioactive material transportation packages  

SciTech Connect

The increased power of computers and computer codes makes the use of nonlinear dynamic finite element analyses attractive for use as a tool used in the design and certification of radioactive material transportation packages. For this analysis technique to be acceptable it must be demonstrated. The technique has the ability to accurately capture the response of the packages to accident environments required by the regulations. The best method of demonstrating this ability is via a series of benchmark analyses. In this paper three benchmark problems involving significant inelastic deformations will be discussed. One of the problems has been analyzed using many different finite element codes. The other two problems involve comparison of finite element calculations to the results form physical tests. The ability of the finite element method to accurately capture the response in these three problems indicates the method should be acceptable for radioactive material transportation package design and certification.

Ammerman, D.J.

1996-10-01

260

Automated internal pipe cutting device  

Microsoft Academic Search

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

William J. Godlewski; Gary S. Haffke; Dale Purvis; Ronald W. Bashar; Stewart D. Jones; Moretti Jr. Henry; James Pimentel

2003-01-01

261

Transient flow in pipe networks  

Microsoft Academic Search

In order to apply the fixed-grid method of characteristics to transient flow in multi-pipe systems, some pipe reaches may not satisfy the Courant condition. Various numerical techniques can be applied for these reaches. In the present study, the finite difference or interpolation techniques are coupled with the method of characteristics. The location of the disproportionate pipe, which does not satisfy

Hossein M. V. Sam Ani; Alireza Khayatzadeh

2002-01-01

262

Sawyer: Running a Benchmark 1 First Draft 1. Introduction ............................................................................................................ 2  

E-print Network

................................................................................................................. 17 #12;Sawyer: Running a Benchmark 1 First Draft Doing Your Own Benchmark Tom Sawyer 15098 Elm ParkSawyer: Running a Benchmark 1 First Draft 1. Introduction

Narasayya, Vivek

263

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

NASA Technical Reports Server (NTRS)

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

Marshburn, J. P.

1972-01-01

264

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

E-print Network

Superior de Ingenieria y Arquitectura Chair of Advisory Committee: Dr. Luciana Barroso A new method based on ratios between stiffness and mass values from the eigenvalue problem is introduced and applied to the benchmark suucture to obtain baseline modal...

Rocha, Ramses Rodriguez

2002-01-01

265

High pressure steam pipe  

Microsoft Academic Search

A detailed dynamic analysis, presented in a series of reports, was conducted on the seismic response and structural safety of key subsystems (steam generator, high pressure steam piping, coal handling equipment, cooling tower, chimney) of Unit No. 3 of TVA at Paradise, Kentucky in order to: (1) determine for the key components the natural frequencies below 50 Hz and the

C. T. Sun; A. S. Ledger; H. Lo

1976-01-01

266

Piping stress handbook  

Microsoft Academic Search

This new edition brings together in one source the formulas and technical data that previously had to be gathered from many scattered sources. The mathematical complexity of refinery, petrochemical, and power-plant piping design requires the use of many highly sophisticated computer programs, all of which require extensive input. The tables in this handbook not only provide these necessary input data

Heiguero

1985-01-01

267

Heat pipe investigations  

NASA Technical Reports Server (NTRS)

Techniques associated with thermal-vacuum and bench testing, along with flight testing of the OAO-C spacecraft heat pipes are outlined, to show that the processes used in heat transfer design and testing are adequate for good performance evaluations.

Marshburn, J. P.

1973-01-01

268

Pipe connector. [LMFBR  

Microsoft Academic Search

A safety test facility for testing sodium-cooled nuclear reactor components includes a reactor vessel and a heat exchanger submerged in sodium in the tank. The reactor vessel and heat exchanger are connected by an expansion\\/deflection pipe coupling comprising a pair of coaxially and slidably engaged tubular elements having radially enlarged opposed end portions of which at least a part is

T. E. Sullivan; J. A. Pardini

1976-01-01

269

Phenomenological model for dispersed bubbly flow in pipes  

Microsoft Academic Search

The ability to predict pressure drop as a function of flow parameters for gas-liquid pipe flows in general and dispersed, bubbly, pipe flows in particular is of considerable importance to a number of industries that utilize two-phase flow systems and processes (for instance, petroleum, chemical, nuclear, and geothermal). An analytical approach to the problem of steady-state, axisymmetrically dispersed, bubbly flow

D. E. Nikitopoulos; Efstathios E. Michaelides

1995-01-01

270

A Complete Piping Analysis With Thermal Stratification Loads  

Microsoft Academic Search

The U. S. Nuclear Regulatory Commission (USNRC) had issued Bulletins 88-08, 88-11, 89-90, and 93-38 to address the concerns and problems due to thermal stratification loading during the life span of normal plant operation. The thermal stratification condition typically will cause pipe to bow in on a long horizontal segment. These conditions have not been commonly considered in piping design.

Milton Dong; Hong Ming Lee; Chii Chern

2002-01-01

271

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

SciTech Connect

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

Chakravarti, B. [KLAD Inc., Naperville, IL (United States)

1996-07-01

272

Improving the design of multilayer pipes  

NASA Astrophysics Data System (ADS)

Production of multilayer steel pipe for gas pipelines up to 1420 mm in diameter, designed for pressures of 10 to 12 MPa, is discussed. The multilayer wall structure, when properly designed, assures high reliability of pipes, primarily due to the reduced danger of sudden failure. However, multiple layers give these pipes certain special properties which under certain conditions may have a negative influence on their performance. Special design decisions are required to limit these negative influences. The possibility of a leak in the inner layer must be considered. In this case the gas penetrates into the gap between the first and second (counting from the inside) layers of the shell. The pressure in the gap becomes as great as the pressure in the pipe and the first layer is no longer functional, resulting in an overload on all subsequent layers. This process is accompanied by gradual elevation in stress. To prevent these problems, several perforations must be made in each shell, passing through all layers except the innermost layer.

1983-08-01

273

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 & amp; Education funded by the Bill & amp; Melinda Gates Foundation

2012-08-01

274

Simple mathematical law benchmarks human confrontations  

NASA Astrophysics Data System (ADS)

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

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

2013-12-01

275

Simple mathematical law benchmarks human confrontations  

PubMed Central

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

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

2013-01-01

276

BEEM: Benchmarks for Explicit Model Checkers  

Microsoft Academic Search

We present Beem — BEnchmarks for Explicit Model check- ers. This benchmark set includes more than 50 parametrized models (300 concrete instances) together with their correctness properties (both safety and liveness). The benchmark set is accompanied by an compre- hensive web portal, which provides detailed information about all models. The web portal also includes information about state spaces and facilities

Radek Pelánek

2007-01-01

277

The Case for Application-Specific Benchmarking  

Microsoft Academic Search

Most performance analysis today uses either microbenchmarks or standard macrobenchmarks (e.g. SPEC, LADDIS, the Andrew benchmark). However, the results of such benchmarks provide little information to indicate how well a particular system will handle a particular application. Such results are, at best, useless and, at worst, misleading. In this paper we argue for an application-directed approach to benchmarking, using performance

Margo I. Seltzer; David Krinsky; Keith A. Smith; Xiaolan Zhang

1999-01-01

278

Benchmarking: Achieving the best in class  

SciTech Connect

Oftentimes, people find the process of organizational benchmarking an onerous task, or, because they do not fully understand the nature of the process, end up with results that are less than stellar. This paper presents the challenges of benchmarking and reasons why benchmarking can benefit an organization in today`s economy.

Kaemmerer, L

1996-05-01

279

Model based energy benchmarking for glass furnace  

Microsoft Academic Search

Energy benchmarking of processes is important for setting energy efficiency targets and planning energy management strategies. Most approaches used for energy benchmarking are based on statistical methods by comparing with a sample of existing plants. This paper presents a model based approach for benchmarking of energy intensive industrial processes and illustrates this approach for industrial glass furnaces.A simulation model for

Vishal Sardeshpande; U. N. Gaitonde; Rangan Banerjee

2007-01-01

280

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

281

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

282

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.

Šarler, B.; Vertnik, R.; Mramor, K.

2012-07-01

283

Drill pipe protector development  

SciTech Connect

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

Thomerson, C.; Kenne, R. [Regal International Corp., Corsicanna, TX (United States); Wemple, R.P. [Sandia National Lab., Albuquerque, NM (United States)] [ed.] [and others

1996-03-01

284

Explosive welding of pipes  

NASA Astrophysics Data System (ADS)

For connection by welding it is suggested to use the explosive welding method. This method is rather new. Nevertheless, it has become commonly used among the technological developments. This method can be advantageous (saving material and physical resources) comparing to its statical analogs (electron-beam welding, argon-arc welding, plasma welding, gas welding, etc.), in particular, in hard-to-reach areas due to their geographic and climatic conditions. The suggestion is to use water as filler. The principle of non-compressibility of liquid under quasi-dynamic loading is used. In one-dimensional gasdynamic and elastic-plastic calculations we determined non-deformed mass of water. Model experiments with pipes having radii R = 57 mm confirmed results of the calculations and the possibility in principle to weld pipes by explosion with use of water as filler.

Drennov, O.; Burtseva, O.; Kitin, A.

2006-08-01

285

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

SciTech Connect

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

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

1999-03-24

286

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

SciTech Connect

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

XU,J.

1999-08-15

287

Pipe cleaning machine  

Microsoft Academic Search

This is a semiautomatic machine for removing rust, mud, and paraffin from the interior and exterior of well pipe or tubing to recondition it for further use. Loading, cleaning and re-racking is carried out by a single operator. The machine has a rectangular, box-like frame which consists of 3 sub-sections and includes a loading rack located on one side of

1965-01-01

288

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

NASA Astrophysics Data System (ADS)

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

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

2012-11-01

289

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

290

Benchmark Dose Analysis via Nonparametric Regression Modeling.  

PubMed

Estimation of benchmark doses (BMDs) in quantitative risk assessment traditionally is based upon parametric dose-response modeling. It is a well-known concern, however, that if the chosen parametric model is uncertain and/or misspecified, inaccurate and possibly unsafe low-dose inferences can result. We describe a nonparametric approach for estimating BMDs with quantal-response data based on an isotonic regression method, and also study use of corresponding, nonparametric, bootstrap-based confidence limits for the BMD. We explore the confidence limits' small-sample properties via a simulation study, and illustrate the calculations with an example from cancer risk assessment. It is seen that this nonparametric approach can provide a useful alternative for BMD estimation when faced with the problem of parametric model uncertainty. PMID:23683057

Piegorsch, Walter W; Xiong, Hui; Bhattacharya, Rabi N; Lin, Lizhen

2013-05-17

291

Benchmark dose analysis via nonparametric regression modeling  

PubMed Central

Estimation of benchmark doses (BMDs) in quantitative risk assessment traditionally is based upon parametric dose-response modeling. It is a well-known concern, however, that if the chosen parametric model is uncertain and/or misspecified, inaccurate and possibly unsafe low-dose inferences can result. We describe a nonparametric approach for estimating BMDs with quantal-response data based on an isotonic regression method, and also study use of corresponding, nonparametric, bootstrap-based confidence limits for the BMD. We explore the confidence limits’ small-sample properties via a simulation study, and illustrate the calculations with an example from cancer risk assessment. It is seen that this nonparametric approach can provide a useful alternative for BMD estimation when faced with the problem of parametric model uncertainty. PMID:23683057

Piegorsch, Walter W.; Xiong, Hui; Bhattacharya, Rabi N.; Lin, Lizhen

2013-01-01

292

Heat pipe technology: A bibliography with abstracts  

NASA Technical Reports Server (NTRS)

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

1971-01-01

293

46 CFR 76.33-15 - Piping.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Piping. 76.33-15 Section 76.33-15...Detecting System, Details § 76.33-15 Piping. (a) Individual pipes shall be not...inch standard pipe size. (b) All piping, valves, and fittings of...

2013-10-01

294

Page 1 of 1 Pipe School  

E-print Network

Page 1 of 1 Track B Pipe School© Sunday, January 22, 2012 Hilton Palacio Del Rio, San Antonio Selection, Terry McArthur, P.E., HDR, Inc. 9:00 Pipe Materials, Terry McArthur, P.E., HDR, Inc. 9:30 Pipe:15 Principles of Pipeline Design and Construction ­ Rigid and Flexible Pipes, Shah Rahman, Northwest Pipe

Texas at Arlington, University of

295

46 CFR 76.33-15 - Piping.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Piping. 76.33-15 Section 76.33-15...Detecting System, Details § 76.33-15 Piping. (a) Individual pipes shall be not...inch standard pipe size. (b) All piping, valves, and fittings of...

2010-10-01

296

46 CFR 76.33-15 - Piping.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 2014-10-01 false Piping. 76.33-15 Section 76.33-15...Detecting System, Details § 76.33-15 Piping. (a) Individual pipes shall be not...inch standard pipe size. (b) All piping, valves, and fittings of...

2014-10-01

297

46 CFR 76.33-15 - Piping.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Piping. 76.33-15 Section 76.33-15...Detecting System, Details § 76.33-15 Piping. (a) Individual pipes shall be not...inch standard pipe size. (b) All piping, valves, and fittings of...

2012-10-01

298

46 CFR 76.33-15 - Piping.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Piping. 76.33-15 Section 76.33-15...Detecting System, Details § 76.33-15 Piping. (a) Individual pipes shall be not...inch standard pipe size. (b) All piping, valves, and fittings of...

2011-10-01

299

Geothermal Heat Pump Benchmarking Report  

SciTech Connect

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

None

1997-01-17

300

Probability of failure in BWR reactor coolant piping: Probabilistic treatment of stress corrosion cracking in 304 and 316NG BWR piping weldments  

SciTech Connect

The purpose of this report is to describe recent expansions of the previously developed PRAISE code to include recent information to make it more applicable to probabilistic analysis of sensitized weldments in BWR piping. The expansions of PRAISE are concentrated in three areas: (1) probabilistic treatment of stress corrosion crack initiation in 304 and 316NG; (2) probabilistic treatment of residual stresses; and (3) benchmarking with field observations of cracking in 304 BWR piping weldments. This expanded version of PRAISE is called PRAISE-CC, and is a significant extension of earlier versions, which considered only piping failures due to the growth of pre-existing crack-like weld defects. PRAISE-CC retains the earlier PRAISE capabilities.

Harris, D.O.; Dedhia, D.D.; Eason, E.D.; Patterson, S.D.

1986-12-01

301

Restaurant Energy Use Benchmarking Guideline  

SciTech Connect

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

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

2011-07-01

302

Insulating Cryogenic Pipes With Frost  

NASA Technical Reports Server (NTRS)

Crystallized water vapor fills voids in pipe insulation. Small, carefully controlled amount of water vapor introduced into dry nitrogen gas before it enters aft fuselage. Vapor freezes on pipes, filling cracks in insulation. Ice prevents gaseous nitrogen from condensing on pipes and dripping on structure, in addition to helping to insulate all parts. Industrial applications include large refrigeration plants or facilities that use cryogenic liquids.

Stephenson, J. G.; Bova, J. A.

1985-01-01

303

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

304

Nonlinear gas oscillations in pipes. I - Theory.  

NASA Technical Reports Server (NTRS)

The problem of forced acoustic oscillations in a pipe is studied theoretically. The oscillations are produced by a moving piston in one end of the pipe, while a variety of boundary conditions ranging from a completely closed to a completely open mouth at the other end are considered. The linear theory predicts large amplitudes near resonance and that nonlinear effects become crucially important. By expanding the equations of motion in a series in the Mach number, both the amplitude and waveform of the oscillation are predicted there. In both the open- and closed-end cases the need for shock waves in some range of parameters is found. The amplitude of the oscillation is different for the two cases, however, being proportional to the square root of the piston amplitude in the closed-end case and to the cube root for the open end.

Jimenez, J.

1973-01-01

305

Synthetic benchmark for modeling flow in 3D fractured media  

NASA Astrophysics Data System (ADS)

Intensity and localization of flows in fractured media have promoted the development of a large range of different modeling approaches including Discrete Fracture Networks, pipe networks and equivalent continuous media. While benchmarked usually within site studies, we propose an alternative numerical benchmark based on highly-resolved Discrete Fracture Networks (DFNs) and on a stochastic approach. Test cases are built on fractures of different lengths, orientations, aspect ratios and hydraulic apertures, issuing the broad ranges of topological structures and hydraulic properties classically observed. We present 18 DFN cases, with 10 random simulations by case. These 180 DFN structures are provided and fully documented. They display a representative variety of the configurations that challenge the numerical methods at the different stages of discretization, mesh generation and system solving. Using a previously assessed mixed hybrid finite element method (Erhel et al., 2009a), we systematically provide reference flow and head solutions. Because CPU and memory requirements stem mainly from system solving, we study direct and iterative sparse linear solvers. We show that the most cpu-time efficient method is a direct multifrontal method for small systems, while conjugate gradient preconditioned by algebraic multrigrid is more relevant at larger sizes. Available results can be used further as references for building up alternative numerical and physical models in both directions of improving accuracy and efficiency.

de Dreuzy, Jean-Raynald; Pichot, Géraldine; Poirriez, Baptiste; Erhel, Jocelyne

2013-01-01

306

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

307

Cryogenic Heat Pipe Experiment (CRYOHP)  

NASA Technical Reports Server (NTRS)

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

Mcintosh, Roy

1992-01-01

308

Black-Box Optimization Benchmarking: Results for the BayEDAcG Algorithm on the Noiseless Function Testbed  

E-print Network

Black-Box Optimization Benchmarking: Results for the BayEDAcG Algorithm on the Noiseless Function experimental results for the BayEDAcG continuous optimization algorithm on the BBOB noise free benchmark problem suite as part of the GECCO'09 Work- shop. 2. ALGORITHM PRESENTATION BayEDAcG is an Estimation

Gallagher, Marcus

309

14 CFR 27.1123 - Exhaust piping.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 false Exhaust piping. 27.1123 Section 27.1123 Aeronautics...Powerplant Exhaust System § 27.1123 Exhaust piping. (a) Exhaust piping must be heat and corrosion resistant, and...

2013-01-01

310

14 CFR 29.1123 - Exhaust piping.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 2011-01-01 false Exhaust piping. 29.1123 Section 29.1123 Aeronautics...Powerplant Exhaust System § 29.1123 Exhaust piping. (a) Exhaust piping must be heat and corrosion resistant, and...

2011-01-01

311

14 CFR 29.1123 - Exhaust piping.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Exhaust piping. 29.1123 Section 29.1123 Aeronautics...Powerplant Exhaust System § 29.1123 Exhaust piping. (a) Exhaust piping must be heat and corrosion resistant, and...

2010-01-01

312

14 CFR 27.1123 - Exhaust piping.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Exhaust piping. 27.1123 Section 27.1123 Aeronautics...Powerplant Exhaust System § 27.1123 Exhaust piping. (a) Exhaust piping must be heat and corrosion resistant, and...

2010-01-01

313

14 CFR 29.1123 - Exhaust piping.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 false Exhaust piping. 29.1123 Section 29.1123 Aeronautics...Powerplant Exhaust System § 29.1123 Exhaust piping. (a) Exhaust piping must be heat and corrosion resistant, and...

2013-01-01

314

14 CFR 29.1123 - Exhaust piping.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 2012-01-01 false Exhaust piping. 29.1123 Section 29.1123 Aeronautics...Powerplant Exhaust System § 29.1123 Exhaust piping. (a) Exhaust piping must be heat and corrosion resistant, and...

2012-01-01

315

14 CFR 27.1123 - Exhaust piping.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 2012-01-01 false Exhaust piping. 27.1123 Section 27.1123 Aeronautics...Powerplant Exhaust System § 27.1123 Exhaust piping. (a) Exhaust piping must be heat and corrosion resistant, and...

2012-01-01

316

14 CFR 29.1123 - Exhaust piping.  

Code of Federal Regulations, 2014 CFR

...2014-01-01 2014-01-01 false Exhaust piping. 29.1123 Section 29.1123 Aeronautics...Powerplant Exhaust System § 29.1123 Exhaust piping. (a) Exhaust piping must be heat and corrosion resistant, and...

2014-01-01

317

14 CFR 27.1123 - Exhaust piping.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 2011-01-01 false Exhaust piping. 27.1123 Section 27.1123 Aeronautics...Powerplant Exhaust System § 27.1123 Exhaust piping. (a) Exhaust piping must be heat and corrosion resistant, and...

2011-01-01

318

14 CFR 27.1123 - Exhaust piping.  

Code of Federal Regulations, 2014 CFR

...2014-01-01 2014-01-01 false Exhaust piping. 27.1123 Section 27.1123 Aeronautics...Powerplant Exhaust System § 27.1123 Exhaust piping. (a) Exhaust piping must be heat and corrosion resistant, and...

2014-01-01

319

Simplified analysis of shrinkage in pipe to pipe butt welds  

Microsoft Academic Search

Generally some shrinkage is typical of butt welding of pipes. Shrinkage due to butt welding could be more pronounced and significant in thin wall stainless steel pipes because the thermal expansion coefficient is roughly one and half times that of carbon steel. An axisymmetric finite element evaluation of hoop shrinkage associated with circumferential butt welds in thin wall stainless steel

Chakrapani Basavaraju

2000-01-01

320

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

321

Present Status and Extensions of the Monte Carlo Performance Benchmark  

NASA Astrophysics Data System (ADS)

The NEA Monte Carlo Performance benchmark started in 2011 aiming to monitor over the years the abilities to perform a full-size Monte Carlo reactor core calculation with a detailed power production for each fuel pin with axial distribution. This paper gives an overview of the contributed results thus far. It shows that reaching a statistical accuracy of 1 % for most of the small fuel zones requires about 100 billion neutron histories. The efficiency of parallel execution of Monte Carlo codes on a large number of processor cores shows clear limitations for computer clusters with common type computer nodes. However, using true supercomputers the speedup of parallel calculations is increasing up to large numbers of processor cores. More experience is needed from calculations on true supercomputers using large numbers of processors in order to predict if the requested calculations can be done in a short time. As the specifications of the reactor geometry for this benchmark test are well suited for further investigations of full-core Monte Carlo calculations and a need is felt for testing other issues than its computational performance, proposals are presented for extending the benchmark to a suite of benchmark problems for evaluating fission source convergence for a system with a high dominance ratio, for coupling with thermal-hydraulics calculations to evaluate the use of different temperatures and coolant densities and to study the correctness and effectiveness of burnup calculations. Moreover, other contemporary proposals for a full-core calculation with realistic geometry and material composition will be discussed.

Hoogenboom, J. Eduard; Petrovic, Bojan; Martin, William R.

2014-06-01

322

Pipe Insulation Economies  

E-print Network

CALCIUM SILICATE ENTER 2 FOAMED URETHANE ENTER 3 MINERAL FIBER ENTER 4 FOAMED GLASS ENTER 5 PERLITE ENTER 6 WHAT IS YOUR INSULATION (1-6)? 2 WHAT IS THE WIND SPEED IN MILES-PER HOUR? 20 WHAT IS THE AMORTIZATION PERIOD IN YEARS? S WHAT... PRINT"WHAT IS THE OUTSIDE RADIUS OF THE PIPE";:INPUT R1:CLS 120 TM=(T1+T3)/2 130 PRINT"SELECT THE TYPE OF INSULATION FROM THIS L1ST: 1I 140 PRINT" FIBERGLASS ENTER 1" 150 PRINT" CALCIUM SILICATE ENTER 2" 160 PRINT" FOAMED URETHANE ENTER 3" 170...

Schilling, R. E.

323

Finite element analysis and design of large diameter flexible vertical pipes subjected to incremental compacted backfill loads and creep effects  

E-print Network

OF TABLES XV i i Table 1. "Datum Case" Structural Responses of Vertical Flexible HDPE Pipe Manhole Subjected to Complete Height Backfill Load . 2. Structural Responses of the Flexible HDPE Vertical Pipe of the Example Problem 3. Summary... plastic pipes are made either as smooth-wall or as profile-wall. The purpose of a profile wall (Fig. 2) is to achieve a higher degree of stiffness-to-weight ratio than that of a smooth pipe, Flexible pipes normally fail in deflection in contrast...

Hossain, Mohammad Kabir

1990-01-01

324

Full-signature real-time corrosion detection of underground casing pipes  

Microsoft Academic Search

Corrosion monitoring and early detection of pits and wall thinning for casing pipes are considerably important to gas and petroleum industries since the frequently occurring corrosion at the internal or external parts of those steel casing pipes used in underground gas storage or oil fields causes production and environmental protection problems. In this paper, a new version of the direct

Jiming Yin; Mi Lu; J. Pineda de Gyvez

2000-01-01

325

Application of ground-penetrating radar to the identification of subsurface piping in blanket peat  

Microsoft Academic Search

Natural soil pipes are common and significant in upland blanket peat catchments yet there are major problems in finding and defining the subsurface pipe networks. This is particularly important because pipeflow can contribute a large proportion of runoff to the river systems in these upland environments and may significantly influence catchment sediment and solute yields. Traditional methods such as digging

J. Holden; T. P. Burt; M. Vilas

2002-01-01

326

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

327

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

328

Optimum material distributions for prescribed apparent fracture toughness in thick-walled FGM circular pipes  

Microsoft Academic Search

This study treats the inverse problem of evaluating optimum material distributions intending to realize prescribed apparent fracture toughness in thick-walled functionally graded material (FGM) circular pipes. The incompatible eigenstrain induced in the pipes after cooling from the sintering temperature due to the nonhomogeneous coefficient of thermal expansion is taken into consideration. An approximation method of finding stress intensity factors for

A. M. Afsar; H. Sekine

2001-01-01

329

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...

330

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

331

Heat Pipes: An Industrial Application  

E-print Network

pipe exchangers, an industrial case history is presented. The case history involves a retrofit project which added heat pipes to five natural draft process heaters with a combined heat duty of 150 M Btu/hr. A heat recovery of 15 M Btu/hr has resulted...

Murray, F.

1984-01-01

332

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

333

Heat Pipe Blocks Return Flow  

NASA Technical Reports Server (NTRS)

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

Eninger, J. E.

1982-01-01

334

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

335

Building a Copper Pipe "Xylophone."  

ERIC Educational Resources Information Center

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

Lapp, David R.

2003-01-01

336

Vibration analysis methods for piping  

Microsoft Academic Search

Attention is given to flow vibrations in pipe flow induced by singularity points in the piping system. The types of pressure fluctuations induced by flow singularities are examined, including the intense wideband fluctuations immediately downstream of the singularity and the acoustic fluctuations encountered in the remainder of the circuit, and a theory of noise generation by unsteady flow in internal

R. J. Gibert

1981-01-01

337

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

338

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

339

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

340

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

341

Finite element analysis of fluid-filled elastic piping systems  

NASA Technical Reports Server (NTRS)

Two finite element procedures are described for predicting the dynamic response of general 3-D fluid-filled elastic piping systems. The first approach, a low frequency procedure, models each straight pipe or elbow as a sequence of beams. The contained fluid is modeled as a separate coincident sequence axial members (rods) which are tied to the pipe in the lateral direction. The model includes the pipe hoop strain correction to the fluid sound speed and the flexibility factor correction to the elbow flexibility. The second modeling approach, an intermediate frequency procedure, follows generally the original Zienkiewicz-Newton scheme for coupled fluid-structure problems except that the velocity potential is used as the fundamental fluid unknown to symmetrize the coefficient matrices. From comparisons of the beam model predictions to both experimental data and the 3-D model, the beam model is validated for frequencies up to about two-thirds of the lowest fluid-filled labor pipe mode. Accurate elbow flexibility factors are seen to be crucial for effective beam modeling of piping systems.

Everstine, G. C.; Marcus, M. S.; Quezon, A. J.

1983-01-01

342

Rupture hardware minimization in pressurized water reactor piping  

SciTech Connect

For much of the high-energy piping in light reactor systems, fracture mechanics calculations can be used to assure pipe failure resistance, thus allowing the elimination of excessive rupture restraint hardware both inside and outside containment. These calculations use the concept of leak-before-break (LBB) and include part-through-wall flaw fatigue crack propagation, through-wall flaw detectable leakage, and through-wall flaw stability analyses. Performing these analyses not only reduces initial construction, future maintenance, and radiation exposure costs, but also improves the overall safety and integrity of the plant since much more is known about the piping and its capabilities than would be the case had the analyses not been performed. This paper presents the LBB methodology applied a Beaver Valley Power Station- Unit 2 (BVPS-2); the application for two specific lines, one inside containment (stainless steel) and the other outside containment (ferrutic steel), is shown in a generic sense using a simple parametric matrix. The overall results for BVPS-2 indicate that pipe rupture hardware is not necessary for stainless steel lines inside containment greater than or equal to 6-in. (152-mm) nominal pipe size that have passed a screening criteria designed to eliminate potential problem systems (such as the feedwater system). Similarly, some ferritic steel line as small as 3-in. (76-mm) diameter (outside containment) can qualify for pipe rupture hardware elemination.

Mukherjee, S.K.; Ski, J.J. (Duquesne Light Co., Beaver Valley Power Station, Shippingport, PA (US)); Chexal, V.; Norris, D.M. (Electric Power Research Institute, Palo Alto, CA (US)); Goldstein, N.A. Beaudoin, B.F.; Quinones, D.F.; Server, W.L. (Stone and Webster Engineering Corp., Boston, MA (US))

1989-02-01

343

An investigation of corrosion in liquid-metal heat pipes  

SciTech Connect

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

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

1998-08-01

344

Monitoring pipe line stress due to ground displacement  

SciTech Connect

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

Greenwood, J.H. Jr.

1986-04-01

345

Spent Fuel Criticality Benchmark Experiments  

SciTech Connect

Characteristics between commercial spent fuel waste packages (WP), Laboratory Critical Experiments (LCEs), and commercial reactor critical (CRC) evaluations are compared in this work. Emphasis is placed upon comparisons of CRC benchmark results and the relative neutron flux spectra in each system. Benchmark evaluations were performed for four different pressurized water reactors using four different sets of isotopes. As expected, as the number of fission products used to represent the burned fuel inventory approached reality, the closer to unity k{sub eff} became. Examination of material and geometry characteristics indicate several fundamental similarities between the WP and CRC systems. In addition, spectral evaluations were performed on a representative pressurized water reactor CRC, a 21-assembly area of the core modeled in a potential WP configuration, and three LCEs considered applicable benchmarks for storage packages. Fission and absorption reaction spectra as well as relative neutron flux spectra are generated and compared for each system. The energy dependent reaction rates are the product of the neutron flux spectrum and the energy dependent total macroscopic cross section. With constant source distribution functions, and the total macroscopic cross sections for the fuel region in the CRCs and WP being composed of nearly the same isotopics, the resulting relative flux spectra in the CRCs and WP are very nearly the same. Differences in the relative neutron flux spectra between WPs and CRCs are evident in the thermal energy range as expected. However, the relative energy distribution of the absorption, fission, and scattering reaction rates in both the CRCs and the WP are essentially the same.

J.M. Scaglione

2001-07-23

346

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

347

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

348

Vibration analysis methods for piping  

NASA Astrophysics Data System (ADS)

Attention is given to flow vibrations in pipe flow induced by singularity points in the piping system. The types of pressure fluctuations induced by flow singularities are examined, including the intense wideband fluctuations immediately downstream of the singularity and the acoustic fluctuations encountered in the remainder of the circuit, and a theory of noise generation by unsteady flow in internal acoustics is developed. The response of the piping systems to the pressure fluctuations thus generated is considered, and the calculation of the modal characteristics of piping containing a dense fluid in order to obtain the system transfer function is discussed. The TEDEL program, which calculates the vibratory response of a structure composed of straight and curved pipes with variable mechanical characteristics forming a three-dimensional network by a finite element method, is then presented, and calculations of fluid-structural coupling in tubular networks are illustrated.

Gibert, R. J.

1981-09-01

349

Benchmarking for Excellence and the Nursing Process  

NASA Technical Reports Server (NTRS)

Nursing is a service profession. The services provided are essential to life and welfare. Therefore, setting the benchmark for high quality care is fundamental. Exploring the definition of a benchmark value will help to determine a best practice approach. A benchmark is the descriptive statement of a desired level of performance against which quality can be judged. It must be sufficiently well understood by managers and personnel in order that it may serve as a standard against which to measure value.

Sleboda, Claire

1999-01-01

350

Computational Chemistry Comparison and Benchmark Database  

National Institute of Standards and Technology Data Gateway

SRD 101 NIST Computational Chemistry Comparison and Benchmark Database (Web, free access)   The NIST Computational Chemistry Comparison and Benchmark Database is a collection of experimental and ab initio thermochemical properties for a selected set of molecules. The goals are to provide a benchmark set of molecules for the evaluation of ab initio computational methods and allow the comparison between different ab initio computational methods for the prediction of thermochemical properties.

351

The Wisconsin Benchmark: Past, Present, and Future  

Microsoft Academic Search

In 1981 as we were completing the implementation of the DIRECT database machine (DEWI79, BORA82), attention turned to evaluating its performance. At that time no standard database benchmark existed. There were only a few application-specific benchmarks. While application-specific benchmarks measure which database system is best for a particular application, it was very difficult to understand them. We were interested in

David J. Dewitt

1991-01-01

352

NASA Software Engineering Benchmarking Effort  

NASA Technical Reports Server (NTRS)

Benchmarking was very interesting and provided a wealth of information (1) We did see potential solutions to some of our "top 10" issues (2) We have an assessment of where NASA stands with relation to other aerospace/defense groups We formed new contacts and potential collaborations (1) Several organizations sent us examples of their templates, processes (2) Many of the organizations were interested in future collaboration: sharing of training, metrics, Capability Maturity Model Integration (CMMI) appraisers, instructors, etc. We received feedback from some of our contractors/ partners (1) Desires to participate in our training; provide feedback on procedures (2) Welcomed opportunity to provide feedback on working with NASA

Godfrey, Sally; Rarick, Heather

2012-01-01

353

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

354

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

355

Technology for concrete pipe manipulator  

NASA Astrophysics Data System (ADS)

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

Li, Bin; Wang, Dan; Lin, Renzhi

2009-12-01

356

Technology for concrete pipe manipulator  

NASA Astrophysics Data System (ADS)

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

Li, Bin; Wang, Dan; Lin, Renzhi

2010-01-01

357

Precipitation dendrites in turbulent pipe flows  

NASA Astrophysics Data System (ADS)

Surface precipitation in pipelines, as well as freezing in water pipes is of great concern in many industrial applications where scaling phenomena becomes a control problem of pipe-clogging or an efficiency reduction in transport. Flow blockage often occurs even when only a small fraction is deposited non-uniformly on the walls in the form of dendrites. Dendritic patterns are commonly encountered in surface precipitation from supersaturated solutions, e.g. calcite dendrites, as well as in solidification from undercooled liquids, e.g. freezing of water into ice dendrites. We explore the mathematical similarities between precipitation and freezing processes and, in particular, investigate the effect of fluid flow on the precipitation dendrites on pipe walls. We use a phase field approach to model surface growth coupled with a lattice Boltzmann method that simulates a channel flow at varying Reynolds number. The dendrites orientation and shape depend non-trivially on the ratio between advection and diffusion, i.e. the Peclet number, as well as the Reynolds number. Roughness induced vortices near growing dendrites at high flow rates further affect the branch splitting of dendrites. We show how the transport rate in a pipeline may depend on the different dendritic morphologies, and provide estimates for the flow conditions that correspond to most efficient transport regimes.

Angheluta, Luiza; Hawkins, Christopher; Hammer, Øyvind; Jamtveit, Bjørn

2013-04-01

358

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

359

Quantum benchmarking with realistic states of light  

E-print Network

The goal of quantum benchmarking is to certify that imperfect quantum communication devices (e.g., quantum channels, quantum memories, quantum key distribution systems) can still be used for meaningful quantum communication. However, the test states used in quantum benchmarking experiments may be imperfect as well. Many quantum benchmarks are only valid for states which match some ideal form, such as pure states or Gaussian states. We outline how to perform quantum benchmarking using arbitrary states of light. We demonstrate these results using real data taken from a continuous-variable quantum memory.

Nathan Killoran; Mahdi Hosseini; Ben C. Buchler; Ping Koy Lam; Norbert Lütkenhaus

2012-08-27

360

Benchmarking Global Optimization and Constraint Satisfaction Codes  

E-print Network

of applications, including: · Chemical engineering (pooling and blending, separation, heat exchanger network for automatic execution on global optimization and constraint satisfaction software. To ensure that benchmarking

Neumaier, Arnold

361

Benchmarking Global Optimization and Constraint Satisfaction Codes  

E-print Network

of applications, including: #15; Chemical engineering (pooling and blending, separation, heat exchanger network for automatic execution on global optimization and constraint satisfaction software. To ensure that benchmarking

Neumaier, Arnold

362

Numerical solution of a two-scale system for concrete corrosion in sewer pipes Vladimir Chalupecky (chalupecky@math.kyushu-u.ac.jp) Faculty of Mathematics, Kyushu University  

E-print Network

Numerical solution of a two-scale system for concrete corrosion in sewer pipes Vladim´ir Chalupeck-diffusion (RD) systems mod- eling sulfate attack in concrete structures (here: sewer pipes). The systems In [2] we deal with the problem of corrosion of concrete sewer pipes that sustain the attack

Ishii, Hitoshi

363

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

364

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

365

Excitation and scattering of guided waves: relationships between solutions for plates and pipes.  

PubMed

The detection of localized defects such as cracks and corrosion in pipes using guided elastic waves is now an established non-destructive testing procedure. However, the prediction of guided wave excitation and scattering in pipes is a complex three-dimensional (3D) problem with many parameters that can generally only be solved using numerical methods. In many important industrial applications, the diameter of a pipe is much larger than wall thickness. In this case an approximate theory is applicable, when a pipe is considered as an unwrapped isotropic plate. In this paper, a technique for obtaining pipe mode amplitudes in terms of the solution to the forced 3D problem on a plate is presented. The same principle is extended to relate guided wave scattering from defects in plates to scattered circumferential modal amplitudes from defects in pipe. This is of practical benefit as the scattering of guided waves by defects in a plate is a much simpler problem than that in a pipe, and one that, in some cases, can be solved using analytical methods. Results are shown that illustrate the application of the method to reflection from through-thickness circumferential cracks in pipes. PMID:19507944

Velichko, Alexander; Wilcox, Paul D

2009-06-01

366

Benchmarking: A tool to enhance performance  

SciTech Connect

The Office of Environmental Management is bringing Headquarters and the Field together to implement process improvements throughout the Complex through a systematic process of organizational learning called benchmarking. Simply stated, benchmarking is a process of continuously comparing and measuring practices, processes, or methodologies with those of other private and public organizations. The EM benchmarking program, which began as the result of a recommendation from Xerox Corporation, is building trust and removing barriers to performance enhancement across the DOE organization. The EM benchmarking program is designed to be field-centered with Headquarters providing facilitatory and integrative functions on an ``as needed`` basis. One of the main goals of the program is to assist Field Offices and their associated M&O/M&I contractors develop the capabilities to do benchmarking for themselves. In this regard, a central precept is that in order to realize tangible performance benefits, program managers and staff -- the ones closest to the work - must take ownership of the studies. This avoids the ``check the box`` mentality associated with some third party studies. This workshop will provide participants with a basic level of understanding why the EM benchmarking team was developed and the nature and scope of its mission. Participants will also begin to understand the types of study levels and the particular methodology the EM benchmarking team is using to conduct studies. The EM benchmarking team will also encourage discussion on ways that DOE (both Headquarters and the Field) can team with its M&O/M&I contractors to conduct additional benchmarking studies. This ``introduction to benchmarking`` is intended to create a desire to know more and a greater appreciation of how benchmarking processes could be creatively employed to enhance performance.

Munro, J.F. [Oak Ridge National Lab., TN (United States); Kristal, J. [USDOE Assistant Secretary for Environmental Management, Washington, DC (United States); Thompson, G.; Johnson, T. [Los Alamos National Lab., NM (United States)

1996-12-31

367

Piping instability resulting from bellows misalignment  

SciTech Connect

The failure of the single phase bellows and magnet test stand during quench testing of SSC dipole magnet DD0011 has led to much speculation about the inherent stability of operating SSC magnets. This note addresses the problem of instabilities resulting from both translational and angular misalignment between pipes connected by bellows in the general sense and with respect to the SSC single phase system specifically. Note that none of the instabilities referenced here result from bellows 'squirm'. Inelastic bellows failure is not within the scope of this work. The failure mode referenced here is an elastic instability. 3 refs., 7 figs.

Nicol, T.H.

1989-05-30

368

Benchmarking FEniCS for mantle convection simulations  

NASA Astrophysics Data System (ADS)

This paper evaluates the usability of the FEniCS Project for mantle convection simulations by numerical comparison to three established benchmarks. The benchmark problems all concern convection processes in an incompressible fluid induced by temperature or composition variations, and cover three cases: (i) steady-state convection with depth- and temperature-dependent viscosity, (ii) time-dependent convection with constant viscosity and internal heating, and (iii) a Rayleigh-Taylor instability. These problems are modeled by the Stokes equations for the fluid and advection-diffusion equations for the temperature and composition. The FEniCS Project provides a novel platform for the automated solution of differential equations by finite element methods. In particular, it offers a significant flexibility with regard to modeling and numerical discretization choices; we have here used a discontinuous Galerkin method for the numerical solution of the advection-diffusion equations. Our numerical results are in agreement with the benchmarks, and demonstrate the applicability of both the discontinuous Galerkin method and FEniCS for such applications.

Vynnytska, L.; Rognes, M. E.; Clark, S. R.

2013-01-01

369

Modeling coupled blast/structure interaction with Zapotec, benchmark calculations for the Conventional Weapon Effects Backfill (CONWEB) tests.  

SciTech Connect

Modeling the response of buried reinforced concrete structures subjected to close-in detonations of conventional high explosives poses a challenge for a number of reasons. Foremost, there is the potential for coupled interaction between the blast and structure. Coupling enters the problem whenever the structure deformation affects the stress state in the neighboring soil, which in turn, affects the loading on the structure. Additional challenges for numerical modeling include handling disparate degrees of material deformation encountered in the structure and surrounding soil, modeling the structure details (e.g., modeling the concrete with embedded reinforcement, jointed connections, etc.), providing adequate mesh resolution, and characterizing the soil response under blast loading. There are numerous numerical approaches for modeling this class of problem (e.g., coupled finite element/smooth particle hydrodynamics, arbitrary Lagrange-Eulerian methods, etc.). The focus of this work will be the use of a coupled Euler-Lagrange (CEL) solution approach. In particular, the development and application of a CEL capability within the Zapotec code is described. Zapotec links two production codes, CTH and Pronto3D. CTH, an Eulerian shock physics code, performs the Eulerian portion of the calculation, while Pronto3D, an explicit finite element code, performs the Lagrangian portion. The two codes are run concurrently with the appropriate portions of a problem solved on their respective computational domains. Zapotec handles the coupling between the two domains. The application of the CEL methodology within Zapotec for modeling coupled blast/structure interaction will be investigated by a series of benchmark calculations. These benchmarks rely on data from the Conventional Weapons Effects Backfill (CONWEB) test series. In these tests, a 15.4-lb pipe-encased C-4 charge was detonated in soil at a 5-foot standoff from a buried test structure. The test structure was composed of a reinforced concrete slab bolted to a reaction structure. Both the slab thickness and soil media were varied in the test series. The wealth of data obtained from these tests along with the variations in experimental setups provide ample opportunity to assess the robustness of the Zapotec CEL methodology.

Bessette, Gregory Carl

2004-09-01

370

A benchmark model to assess community structure in evolving networks  

E-print Network

Detecting the time evolution of the community structure of networks is crucial to identify major changes in the internal organization of many complex systems, which may undergo important endogenous or exogenous events. This analysis can be done in two ways: considering each snapshot as an independent community detection problem or taking into account the whole evolution of the network. In the first case, one can apply static methods on the temporal snapshots, which correspond to configurations of the system in short time windows, and match afterwards the communities across layers. Alternatively, one can develop dedicated dynamic procedures, so that multiple snapshots are simultaneously taken into account while detecting communities, which allows to keep memory of the flow. To check how well a method of any kind could capture the evolution of communities, suitable benchmarks are needed. Here we propose a model for generating simple dynamic benchmark graphs, based on stochastic block models. In them, the time e...

Granell, Clara; Arenas, Alex; Fortunato, Santo; Gómez, Sergio

2015-01-01

371

DETECTION OF BURIED AGRICULTURAL DRAINAGE PIPE WITH GEOPHYSICAL METHODS  

Technology Transfer Automated Retrieval System (TEKTRAN)

One of the more frustrating problems confronting farmers and land improvement contractors in the Midwest U.S. involves locating buried agricultural drainage pipes. Enhancing the efficiency of soil water removal on land already containing a subsurface drainage system typically involves installing new...

372

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. Hötzl; T. Schneider; L. S. Burn

2000-01-01

373

The cooling of concrete slabs using water pipe networks  

Microsoft Academic Search

The proposed problem concerns a simplifled model to describe the removal of hydration heat from concrete dams during construction using piped water. Large concrete structures are usually made in a series of blocks, because before the construction of the Hoover dam, engineers estimated that if a dam was built in one pour it would take 125 years to cool it

Alvarez Sanchez; Ignacio Gonzalez Andres; Michele Marini; Sarah Mitchell; Nadia Smith

374

Heat pipe technology: A bibliography with abstracts  

NASA Technical Reports Server (NTRS)

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

1971-01-01

375

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

376

Determination of Secondary Encasement Pipe Design Pressure  

SciTech Connect

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

TEDESCHI, A.R.

2000-10-26

377

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

378

46 CFR 108.447 - Piping.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Piping. 108.447 Section 108.447 Shipping...Fire Extinguishing Systems § 108.447 Piping. (a) Each pipe, valve, and fitting...pounds per square inch). (b) All piping for a CO2 system of nominal size...

2013-10-01

379

Structural Assessment of Small Bore Feeder Piping  

E-print Network

BACKGROUND Structural Assessment of Small Bore Feeder Piping Kathryn Tang, Janos Mann, Skerdi. Supervisor: A. N. Sinclair CASE ONE CANDU REACTORS HAVE 380+ SMALL BORE FEEDER PIPES. THE PIPES PIPES AND VALIDATE COMPUTATIONAL METHODS COMPARED TO FULL SCALE TESTS TO FAILURE. THE CLIENT CANDU

380

46 CFR 108.447 - Piping.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Piping. 108.447 Section 108.447 Shipping...Fire Extinguishing Systems § 108.447 Piping. (a) Each pipe, valve, and fitting...pounds per square inch). (b) All piping for a CO2 system of nominal size...

2012-10-01

381

Page 1 of 1 Pipe School  

E-print Network

Page 1 of 1 Track A Pipe School© Presented by: Terry McArthur; PE, CDT Senior Professional Registration 8:15 Overview of Different Pipe Materials ­ An overview of different pipe materials and their capabilities and limitations for pressure and gravity applications. 9:00 Rigid and Flexible Pipes: A comparison

Huang, Haiying

382

46 CFR 108.447 - Piping.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Piping. 108.447 Section 108.447 Shipping...Fire Extinguishing Systems § 108.447 Piping. (a) Each pipe, valve, and fitting...pounds per square inch). (b) All piping for a CO2 system of nominal size...

2011-10-01

383

46 CFR 108.447 - Piping.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 2014-10-01 false Piping. 108.447 Section 108.447 Shipping...Fire Extinguishing Systems § 108.447 Piping. (a) Each pipe, valve, and fitting...pounds per square inch). (b) All piping for a CO2 system of nominal size...

2014-10-01

384

46 CFR 56.10-5 - Pipe.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 false Pipe. 56.10-5 Section...CONTINUED) MARINE ENGINEERING PIPING SYSTEMS AND...Components § 56.10-5 Pipe. (a) General...2) Copper and brass pipe for air may be used in...accordance with the allowable stresses found from table...

2014-10-01

385

Grey Cast Iron Water Pipe Metallurgy  

Microsoft Academic Search

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 to produce a methodology for determining the residual life of grey cast iron pipes.

J. M. Makar; B. Rajani

386

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

387

Heat pipe experiment on SPAS 01  

NASA Astrophysics Data System (ADS)

The second flight of Challenger carried a heat pipe experiment, designed to measure the performance of constant conductance heat pipe diodes over a period of 16 hr. The experiment platform and the flight results on variable conductance heat pipe housekeeping radiators, including the temperature distribution at these heat pipe versus experiment time are presented. All equipment is shown to be space qualified.

Kock, H.; Kreeb, H.; Savage, C.

1986-08-01

388

Abrasion protection in process piping  

SciTech Connect

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

Accetta, J. [Abresist Corp., Urbana, IN (United States)

1996-07-01

389

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

390

A Benchmark Diagnostic Model Generation System  

Microsoft Academic Search

It is critical to use automated generators for synthetic models and data given the sparsity of benchmark models for empirical analysis and the cost of generating models by hand. We describe an automated generator for benchmark models that is based on using a compositional modeling framework and employs graphical models for the system topology. We propose a three-step process for

Jun Wang; Gregory M. Provan

2010-01-01

391

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

392

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

393

Communication Characteristics in the NAS Parallel Benchmarks  

E-print Network

Communication Characteristics in the NAS Parallel Benchmarks Ahmad Faraj Xin Yuan Department-- In this paper, we investigate the communication characteris- tics of the Message Passing Interface (MPI) implementation of the NAS parallel benchmarks and study the effectiveness of com- piled communication for MPI

Yuan, Xin

394

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

395

Generating benchmarking indicators for employee job satisfaction  

Microsoft Academic Search

This paper aims to generate benchmarking indicators for employee job satisfaction using a large size sample including various industrial and occupational sectors. Job satisfaction was measured using the Job Satisfaction Scale developed by the Sheffield Institute of Work Psychology and published with a benchmarking manual in 2007. The International Standard Classification of Occupations developed by the International Labour Organization was

Marwan T. Al-Zoubi

2012-01-01

396

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

397

The PRISM Benchmark Suite Marta Kwiatkowska  

E-print Network

The PRISM Benchmark Suite Marta Kwiatkowska Department of Computer Science, University of Oxford.a.parker@cs.bham.ac.uk Abstract--We present the PRISM benchmark suite: a col- lection of probabilistic models and property of which is the PRISM model checker [1]. Many models for use with PRISM are publicly available, either

Paris-Sud XI, Université de

398

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

399

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

400

Characterizing Microprocessor Benchmarks Towards Understanding the Workload Design Space  

E-print Network

#12;Characterizing Microprocessor Benchmarks Towards Understanding the Workload Design Space The University of Texas at Austin December 2003 #12;Characterizing Microprocessor Benchmarks Towards #12;Characterizing Microprocessor Benchmarks Towards Understanding the Workload Design Space

John, Lizy Kurian

401

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

402

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

403

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

404

Heat Pipe Applications in Sorption Refrigerators  

Microsoft Academic Search

\\u000a Some sorption refrigeration machines (sorption technologies) developed in Belarus are presented in this paper with emphasises\\u000a on different heat pipes application: conventional heat pipes, heat pipe panels, loop heat pipes, vapour-dynamic thermosyphons,\\u000a etc. Heat pipes are very flexible systems with regards to the effective thermal control. They can easily be implemented inside\\u000a sorption refrigerators and other types of refrigerators [1].

L. L. Vasiliev; A. G. Kulakov

405

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

406

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

407

Method for casting polyethylene pipe  

NASA Technical Reports Server (NTRS)

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

Elam, R. M., Jr.

1973-01-01

408

Heat pipe radiators for space  

NASA Technical Reports Server (NTRS)

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

Sellers, J. P.

1976-01-01

409

Loop Heat Pipe Startup Behaviors  

NASA Technical Reports Server (NTRS)

A loop heat pipe must start successfully before it can commence its service. The start-up transient represents one of the most complex phenomena in the loop heat pipe operation. This paper discusses various aspects of loop heat pipe start-up behaviors. Topics include the four start-up scenarios, the initial fluid distribution between the evaporator and reservoir that determines the start-up scenario, factors that affect the fluid distribution between the evaporator and reservoir, difficulties encountered during the low power start-up, and methods to enhance the start-up success. Also addressed are the thermodynamic constraint between the evaporator and reservoir in the loop heat pipe operation, the superheat requirement for nucleate boiling, pressure spike and pressure surge during the start-up transient, and repeated cycles of loop start-up andshutdown under certain conditions.

Ku, Jentung

2014-01-01

410

Meteoroid Protection Methods for Spacecraft Radiators Using Heat Pipes  

NASA Technical Reports Server (NTRS)

Various aspects of achieving a low mass heat pipe radiator for the nuclear electric propulsion spacecraft were studied. Specific emphasis was placed on a concept applicable to a closed Brayton cycle power sub-system. Three aspects of inter-related problems were examined: (1) the armor for meteoroid protection, (2) emissivity of the radiator surface, and (3) the heat pipe itself. The study revealed several alternatives for the achievement of the stated goal, but a final recommendation for the best design requires further investigation.

Ernst, D. M.

1979-01-01

411

Benchmarking a Visual-Basic based multi-component one-dimensional reactive transport modeling tool  

NASA Astrophysics Data System (ADS)

We present the details of a comprehensive numerical modeling tool, RT1D, which can be used for simulating biochemical and geochemical reactive transport problems. The code can be run within the standard Microsoft EXCEL Visual Basic platform, and it does not require any additional software tools. The code can be easily adapted by others for simulating different types of laboratory-scale reactive transport experiments. We illustrate the capabilities of the tool by solving five benchmark problems with varying levels of reaction complexity. These literature-derived benchmarks are used to highlight the versatility of the code for solving a variety of practical reactive transport problems. The benchmarks are described in detail to provide a comprehensive database, which can be used by model developers to test other numerical codes. The VBA code presented in the study is a practical tool that can be used by laboratory researchers for analyzing both batch and column datasets within an EXCEL platform.

Torlapati, Jagadish; Prabhakar Clement, T.

2013-01-01

412

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

413

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

414

Effects of pipe diameters on the pressures during delayed load rejection in high-head pumped storage power stations  

NASA Astrophysics Data System (ADS)

High-head pumped storage power stations face serious problems related to the transient process, especially in the area of delayed load rejection in stations with annular piping layouts. The controlled pressures are adversely affected, which leads to many problems in the engineering design phase. In this study, we investigated this condition through theoretical analysis, numerical simulation, and actual engineering practice. We concluded that the root cause of the pressure issues is the flow switching resulted from the non-synchronous changes in pressure between each branch pipe. Moreover, we examined the impact of the diameters of the upstream main pipe and branch pipe on the controlled pressures and determined that the diameter of the branch pipe has a major influence on the pressures as it changes the flow switching rate. A similar investigation was conducted for downstream pipes. Our conclusions can be applied to actual engineering practice for high-head pumped storage power stations.

Zeng, W.; Yang, J. D.

2014-12-01

415

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

416

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

417

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

418

Warped Extra Dimensional Benchmarks for Snowmass 2013  

E-print Network

The framework of a warped extra dimension with the Standard Model (SM) fields propagating in it is a very well-motivated extension of the SM since it can address both the Planck-weak and flavor hierarchy problems of the SM. We consider signals at the 14 and 33 TeV large hadron collider (LHC) resulting from the direct production of the new particles in this framework, i.e.,Kaluza-Klein (KK) excitations of the SM particles. We focus on spin-1 (gauge boson) and spin-2 (graviton) KK particles and their decays to top/bottom quarks (flavor-conserving) and W/Z and Higgs bosons, in particular. We propose two benchmarks for this purpose, with the right-handed (RH) or LH top quark, respectively, being localized very close to the TeV end of the extra dimension. We present some new results at the 14 TeV (with 300 fb$^-1$ and 3000 fb$^-1$) and 33 TeV LHC. We find that the prospects for discovery of these particles are quite promising, especially at the high-luminosity upgrade.

Kaustubh Agashe; Oleg Antipin; Mihailo Backovi?; Aaron Effron; Alex Emerman; Johannes Erdmann; Tobias Golling; Shrihari Gopalakrishna; Tuomas Hapola; Shih-Chieh Hsu; José Juknevich; Seung J. Lee; Tanumoy Mandal; August Miller; Edward Moyse; Tuhin Subhra Mukherjee; Chris Pollard; Soumya Sadhukhan; Daniel Whiteson; Stephane Willocq

2013-09-30

419

Analytical Benchmark Test Set for Criticality Code Verification  

SciTech Connect

A number of published numerical solutions to analytic eigenvalue (k{sub eff}) and eigenfunction equations are summarized for the purpose of creating a criticality verification benchmark test set. The 75-problem test set allows the user to verify the correctness of a criticality code for infinite medium and simple geometries in one- and two-energy groups, one- and two-media, and both isotropic and linearly anisotropic neutron scattering. A three- and six-energy group infinite medium problem are also included in the test set. The problem specifications will produce both k{sub eff}=1 and the quoted k{sub {infinity}} to at least five decimal places. Additional uses of the test set for code verification are also discussed. Los Alamos report LA-13511 contains the details of all 75 test problems.

Sood, A.; Forster, R.A.; Parson, D.K.

1999-09-20

420

Convective instability in pipe flow through a sudden expansion  

NASA Astrophysics Data System (ADS)

Flow through a sudden expansion in a pipe has been the subject of a lot of recent scientific interest. The geometry occurs in many industrial processes, from heat exchangers to combustion chambers, and is closely related to the physiological problem of flow through a stenosis. The inlet flow from the upstream pipe is Poiseuille, which forms a central jet surrounded by a recirculating eddy in the expanded downstream pipe. Recently we showed that this kind of flow passes through a symmetry breaking bifurcation before the onset of both intermittent and fully periodic time-dependent effects. We have now investigated the intermittency in more detail and find that the flow becomes convectively unstable. A wave packet emerges from the laminar state and grows to a maximum size of several diameters before decaying.

Seddon, James

2009-03-01

421

Experimental observation of nonlinear traveling waves in turbulent pipe flow.  

PubMed

Transition to turbulence in pipe flow is one of the most fundamental and longest-standing problems in fluid dynamics. Stability theory suggests that the flow remains laminar for all flow rates, but in practice pipe flow becomes turbulent even at moderate speeds. This transition drastically affects the transport efficiency of mass, momentum, and heat. On the basis of the recent discovery of unstable traveling waves in computational studies of the Navier-Stokes equations and ideas from dynamical systems theory, a model for the transition process has been suggested. We report experimental observation of these traveling waves in pipe flow, confirming the proposed transition scenario and suggesting that the dynamics associated with these unstable states may indeed capture the nature of fluid turbulence. PMID:15361619

Hof, Björn; van Doorne, Casimir W H; Westerweel, Jerry; Nieuwstadt, Frans T M; Faisst, Holger; Eckhardt, Bruno; Wedin, Hakan; Kerswell, Richard R; Waleffe, Fabian

2004-09-10

422

Well pipe float valve  

SciTech Connect

This patent describes a drill pipe float assembly comprising an elongated cylindrical cage having upper and lower rings joined by diametrically opposite vertical wall members. The upper ring has a downwardly facing valve seat on its inner perimeter. The assembly includes a valve stem guide member supported by the lower ring including a central vertical bearing sleeve slidable guiding the depending end portion of a valve stem. The valve stem has a valve on its upper end including an elastomer seal seating and unseating on the valve seat in response to the direction of fluid flow through the ring members, cylindrical spring retainer on the valve stem in contact with the valve seal, and a helical spring surrounding the valve stem and biasing the valve toward its seat, the improvement comprising: means secured to the respective confronting end surfaces of the spring retainer and the valve stem guide sleeve for interdigitated engagement in response to fluid flow in one direction through the float assembly.

Taylor, J.S.

1986-11-18

423

Piping inspection round robin  

SciTech Connect

The piping inspection round robin was conducted in 1981 at the Pacific Northwest National Laboratory (PNNL) to quantify the capability of ultrasonics for inservice inspection and to address some aspects of reliability for this type of nondestructive evaluation (NDE). The round robin measured the crack detection capabilities of seven field inspection teams who employed procedures that met or exceeded the 1977 edition through the 1978 addenda of the American Society of Mechanical Engineers (ASME) Section 11 Code requirements. Three different types of materials were employed in the study (cast stainless steel, clad ferritic, and wrought stainless steel), and two different types of flaws were implanted into the specimens (intergranular stress corrosion cracks (IGSCCs) and thermal fatigue cracks (TFCs)). When considering near-side inspection, far-side inspection, and false call rate, the overall performance was found to be best in clad ferritic, less effective in wrought stainless steel and the worst in cast stainless steel. Depth sizing performance showed little correlation with the true crack depths.

Heasler, P.G.; Doctor, S.R. [Pacific Northwest National Lab., Richland, WA (United States)

1996-04-01

424

ICSBEP Benchmarks For Nuclear Data Applications  

NASA Astrophysics Data System (ADS)

The International Criticality Safety Benchmark Evaluation Project (ICSBEP) was initiated in 1992 by the United States Department of Energy. The ICSBEP became an official activity of the Organization for Economic Cooperation and Development (OECD) — Nuclear Energy Agency (NEA) in 1995. Representatives from the United States, United Kingdom, France, Japan, the Russian Federation, Hungary, Republic of Korea, Slovenia, Serbia and Montenegro (formerly Yugoslavia), Kazakhstan, Spain, Israel, Brazil, Poland, and the Czech Republic are now participating. South Africa, India, China, and Germany are considering participation. The purpose of the ICSBEP is to identify, evaluate, verify, and formally document a comprehensive and internationally peer-reviewed set of criticality safety benchmark data. The work of the ICSBEP is published as an OECD handbook entitled "International Handbook of Evaluated Criticality Safety Benchmark Experiments." The 2004 Edition of the Handbook contains benchmark specifications for 3331 critical or subcritical configurations that are intended for use in validation efforts and for testing basic nuclear data. New to the 2004 Edition of the Handbook is a draft criticality alarm / shielding type benchmark that should be finalized in 2005 along with two other similar benchmarks. The Handbook is being used extensively for nuclear data testing and is expected to be a valuable resource for code and data validation and improvement efforts for decades to come. Specific benchmarks that are useful for testing structural materials such as iron, chromium, nickel, and manganese; beryllium; lead; thorium; and 238U are highlighted.

Briggs, J. Blair

2005-05-01

425

The reflection of guided waves from simple dents in pipes.  

PubMed

Guided elastic waves have been anticipated as a rapid screening technique for pipe inspection. Dents occurring in pipes are a severe problem which may lead to the possibility of pipe failure. A study of the reflection characteristics of guided waves from dents of varying geometrical profile in pipes is investigated through experiments. Dented region is represented by a series of circumferential cross-sections and its geometric parameters are described by axial length and the maximum and minimum outer diameters. Both single and double sided dents are mechanically simulated in hollow aluminum pipes and then experimentally tested by exciting the longitudinal L(0,2) mode. A quantitative parameter, so-called deformation rate relating to the maximum and minimum outer diameters of the dents is defined to evaluate the effect of the extent of the deformation on the reflection. For both types of dents, it is shown that the reflection coefficients of the L(0,2) mode are all approximately a linear function of their respective deformation rates. Mode conversion occurs at the dents and reflections of the F(1,3) mode are identified. The results show that the amplitude of the reflected F(1,3) mode is generally higher when the dent has stronger non-axisymmetric features. PMID:25497001

Ma, Shuyi; Wu, Zhanjun; Wang, Yishou; Liu, Kehai

2015-03-01

426

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

427

Clinically meaningful performance benchmarks in MS  

PubMed Central

Objective: Identify and validate clinically meaningful Timed 25-Foot Walk (T25FW) performance benchmarks in individuals living with multiple sclerosis (MS). Methods: Cross-sectional study of 159 MS patients first identified candidate T25FW benchmarks. To characterize the clinical meaningfulness of T25FW benchmarks, we ascertained their relationships to real-life anchors, functional independence, and physiologic measurements of gait and disease progression. Candidate T25FW benchmarks were then prospectively validated in 95 subjects using 13 measures of ambulation and cognition, patient-reported outcomes, and optical coherence tomography. Results: T25FW of 6 to 7.99 seconds was associated with a change in occupation due to MS, occupational disability, walking with a cane, and needing “some help” with instrumental activities of daily living; T25FW ?8 seconds was associated with collecting Supplemental Security Income and government health care, walking with a walker, and inability to do instrumental activities of daily living. During prospective benchmark validation, we trichotomized data by T25FW benchmarks (<6 seconds, 6–7.99 seconds, and ?8 seconds) and found group main effects on 12 of 13 objective and subjective measures (p < 0.05). Conclusions: Using a cross-sectional design, we identified 2 clinically meaningful T25FW benchmarks of ?6 seconds (6–7.99) and ?8 seconds. Longitudinal and larger studies are needed to confirm the clinical utility and relevance of these proposed T25FW benchmarks and to parse out whether there are additional benchmarks in the lower (<6 seconds) and higher (>10 seconds) ranges of performance. PMID:24174581

Motl, Robert W.; Scagnelli, John; Pula, John H.; Sosnoff, Jacob J.; Cadavid, Diego

2013-01-01

428

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

429

Pseudo-nonlinear dynamic analysis of buckled pipes  

NASA Astrophysics Data System (ADS)

In this study, the post-divergence behavior of fluid-conveying pipes supported at both ends is investigated using the nonlinear equations of motion. The governing equation exhibits a cubic nonlinearity arising from mid-plane stretching. Exact solutions for post-buckling configurations of pipes with fixed-fixed, fixed-hinged, and hinged-hinged boundary conditions are investigated. The pipe is stable at its original static equilibrium position until the flow velocity becomes high enough to cause a supercritical pitchfork bifurcation, and the pipe loses stability by static divergence. In the supercritical fluid velocity regime, the equilibrium configuration becomes unstable and bifurcates into multiple equilibrium positions. To investigate the vibrations that occur in the vicinity of a buckled equilibrium position, the pseudo-nonlinear vibration problem around the first buckled configuration is solved precisely using a new solution procedure. By solving the resulting eigenvalue problem, the natural frequencies and the associated mode shapes of the pipe are calculated. The dynamic stability of the post-buckling configurations obtained in this manner is investigated. The first buckled shape is a stable equilibrium position for all boundary conditions. The buckled configurations beyond the first buckling mode are unstable equilibrium positions. The natural frequencies of the lowest vibration modes around each of the first two buckled configurations are presented. Effects of the system parameters on pipe behavior as well as the possibility of a subcritical pitchfork bifurcation are also investigated. The results show that many internal resonances might be activated among the vibration modes around the same or different buckled configurations.

Gültekin S?n?r, B.

2013-02-01

430

NEP heat pipe radiators. [Nuclear Electric Propulsion  

NASA Technical Reports Server (NTRS)

This paper covers improvements of heat pipe radiators for the thermionic NEP design. Liquid metal heat pipes are suitable as spacecraft radiator elements because of high thermal conductance, low mass and reliability, but the NEP thermionic system design was too large and difficult to fabricate. The current integral collector-radiator design consisting of several layers of thermionic converters, the annular-tangential collector heat pipe, the radiator heat pipe, and the transition zone designed to minimize the temperature difference between the collector heat pipe and radiator heat pipe are described. Finally, the design of micrometeoroid armor protection and the fabrication of the stainless steel annular heat pipe with a tangential arm are discussed, and it is concluded that the heat rejection system for the thermionic NEP system is well advanced, but the collector-radiator heat pipe transition and the 8 to 10 m radiator heat pipe with two bends require evaluation.

Ernst, D. M.

1979-01-01

431

Collective Problem Solving through Coordinated Reaction  

E-print Network

of problem solving is con­ straint satisfaction problems. We have applied the method­ ology to job shop scheduling, an NP­complete constraint satisfaction problem. Experimental results on a benchmark suite on problems of larger sizes and showed favorable scaling­up characteristics. KeyW ords--- Collective Problem

Yu, Bin

432

Electrohydrodynamically augmented micro heat pipes  

NASA Astrophysics Data System (ADS)

For high power density dissipation, micro heat pipes and micro grooves have demonstrated much promise. Several experimental investigations were conducted to evaluate the potential benefits of electrohydrodynamic (EHD) forces on the operation of micro heat pipes. In these experiments, electric fields were used to orient and guide the flow of the dielectric liquid within the micro heat pipes from the condenser to the evaporator. The first series of experiments indicate that the heat transport capability of the EHD micro heat pipes is increased by up to 6 times of that of conventional ones. Simultaneously, a theoretical model was developed to predict the maximum heat transport capability for various electric field intensities and micro heat pipe geometries. The analytical model agrees well with the experimental results. The model shows that large pore sizes are optimal from a heat transport capacity perspective. Finally, a critical assessment of the experimental results suggest an alternative design capable of achieving as much as a 240 times improvement in the heat transport capacity in comparison to traditional micro heat pipes. Another means to augment the heat transport capacity of micro heat pipes is to employ an ion-drag pumping. An analytical model is developed to evaluate the maximum heat transport capacity as a function of the applied electric field. The predictions indicate that ion drag pumping can achieve a four times increase in heat transport capacity under the application of an electric field relative to what would exist in the absence of a field. A transient analytical model was developed to permit variation of the electric field with applied thermal load. A proportional-integral-derivative controller was used to simulate active temperature control. The feasibility of achieving active temperature control was demonstrated experimentally. Finally, a simpler EHD enhanced micro groove model was constructed and tested. A pair of electrodes was used as a liquid artery to convey the working liquid from the condenser to the evaporator. A six times increase of the heat transport capability was obtained.

Yu, Zhiquan

2001-12-01

433

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

434

[Study on the automatic parameters identification of water pipe network model].  

PubMed

Based on the problems analysis on development and application of water pipe network model, the model parameters automatic identification is regarded as a kernel bottleneck of model's application in water supply enterprise. The methodology of water pipe network model parameters automatic identification based on GIS and SCADA database is proposed. Then the kernel algorithm of model parameters automatic identification is studied, RSA (Regionalized Sensitivity Analysis) is used for automatic recognition of sensitive parameters, and MCS (Monte-Carlo Sampling) is used for automatic identification of parameters, the detail technical route based on RSA and MCS is presented. The module of water pipe network model parameters automatic identification is developed. At last, selected a typical water pipe network as a case, the case study on water pipe network model parameters automatic identification is conducted and the satisfied results are achieved. PMID:20329520

Jia, Hai-Feng; Zhao, Qi-Feng

2010-01-01

435

Numisheet2005 Benchmark Analysis on Forming of an Automotive Underbody Cross Member: Benchmark 2  

SciTech Connect

This report presents an international cooperation benchmark effort focusing on simulations of a sheet metal stamping process. A forming process of an automotive underbody cross member using steel and aluminum blanks is used as a benchmark. Simulation predictions from each submission are analyzed via comparison with the experimental results. A brief summary of various models submitted for this benchmark study is discussed. Prediction accuracy of each parameter of interest is discussed through the evaluation of cumulative errors from each submission.

Buranathiti, Thaweepat; Cao Jian [Department of Mechanical Engineering, Northwestern University, Evanston, Illinois 60208 (United States)

2005-08-05

436

DOE Commercial Building Benchmark Models: Preprint  

SciTech Connect

To provide a consistent baseline of comparison and save time conducting such simulations, the U.S. Department of Energy (DOE) has developed a set of standard benchmark building models. This paper will provide an executive summary overview of these benchmark buildings, and how they can save building analysts valuable time. Fully documented and implemented to use with the EnergyPlus energy simulation program, the benchmark models are publicly available and new versions will be created to maintain compatibility with new releases of EnergyPlus. The benchmark buildings will form the basis for research on specific building technologies, energy code development, appliance standards, and measurement of progress toward DOE energy goals. Having a common starting point allows us to better share and compare research results and move forward to make more energy efficient buildings.

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

2008-07-01

437

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

438

Applications of disease benchmarks and case presentations.  

PubMed

A large dataset of integrated pharmacy and medical claims, extracted from independent third-party databases, is being combined with disease benchmarking technology to facilitate analysis of inpatient, outpatient, ancillary services, and pharmaceutical utilization and costs. The Disease Benchmarks Program was developed to create opportunities for health care decision makers to evaluate the entire health care continuum in a disease-specific fashion. The Benchmarks program is valuable because of its flexibility and because it depicts what is occurring in clinical practice. It can be customized and also show regional variations in treatment. The possible applications of benchmarking applications are discussed in the case presentations of otitis externa, acute otitis media with tympanostomy tubes, and Sjorgren's syndrome. PMID:15667243

Pill, Michael W

2005-01-01

439

XWeB: The XML Warehouse Benchmark  

NASA Astrophysics Data System (ADS)

With the emergence of XML as a standard for representing business data, new decision support applications are being developed. These XML data warehouses aim at supporting On-Line Analytical Processing (OLAP) operations that manipulate irregular XML data. To ensure feasibility of these new tools, important performance issues must be addressed. Performance is customarily assessed with the help of benchmarks. However, decision support benchmarks do not currently support XML features. In this paper, we introduce the XML Warehouse Benchmark (XWeB), which aims at filling this gap. XWeB derives from the relational decision support benchmark TPC-H. It is mainly composed of a test data warehouse that is based on a unified reference model for XML warehouses and that features XML-specific structures, and its associate XQuery decision support workload. XWeB's usage is illustrated by experiments on several XML database management systems.

Mahboubi, Hadj; Darmont, Jérôme

440

Public Relations in Accounting: A Benchmark Study.  

ERIC Educational Resources Information Center

Reports on a national study of one segment of the professional services market: the accounting profession. Benchmark data on CPA firms' attitudes toward and uses of public relations are presented and practical and theoretical/research issues are discussed. (JC)

Pincus, J. David; Pincus, Karen V.

1987-01-01

441

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.

442

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

443

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

444

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

445

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

446

Benchmark testing and independent verification of the VS2DT computer code  

SciTech Connect

The finite difference flow and transport simulator VS2DT was benchmark tested against several other codes which solve the same equations (Richards equation for flow and the Advection-Dispersion equation for transport). The benchmark problems investigated transient two-dimensional flow in a heterogeneous soil profile with a localized water source at the ground surface. The VS2DT code performed as well as or better than all other codes when considering mass balance characteristics and computational speed. It was also rated highly relative to the other codes with regard to ease-of-use. Following the benchmark study, the code was verified against two analytical solutions, one for two-dimensional flow and one for two-dimensional transport. These independent verifications show reasonable agreement with the analytical solutions, and complement the one-dimensional verification problems published in the code`s original documentation.

McCord, J.T. [Sandia National Labs., Albuquerque, NM (United States). Environmental Risk Assessment and Risk Management Dept.; Goodrich, M.T. [IT Corp., Albuquerque, NM (United States)

1994-11-01

447

Benchmarking with high-order nodal diffusion methods  

SciTech Connect

Significant progress in the solution of multidimensional neutron diffusion problems was made in the late 1970s with the introduction of nodal methods. Modern nodal reactor analysis codes provide significant improvements in both accuracy and computing speed over earlier codes based on fine-mesh finite difference methods. In the past, the performance of advanced nodal methods was determined by comparisons with fine-mesh finite difference codes. More recently, the excellent spatial convergence of nodal methods has permitted their use in establishing reference solutions for some important bench-mark problems. The recent development of the self-consistent high-order nodal diffusion method and its subsequent variational formulation has permitted the calculation of reference solutions with one node per assembly mesh size. In this paper, we compare results for four selected benchmark problems to those obtained by high-order response matrix methods and by two well-known state-of-the-art nodal methods (the [open quotes]analytical[close quotes] and [open quotes]nodal expansion[close quotes] methods).

Tomasevic, D.; Larsen, E.W. (Univ. of Michigan, Ann Arbor, MI (United States))

1993-01-01

448

Texture Analysis Experiments with Meastex and Vistex Benchmarks  

Microsoft Academic Search

The analysis of texture in images is an important area of study. Image benchmarks such as Meastex and Vistex have been developed for researchers to compare their experiments on these texture benchmarks. In this paper we compare five different texture analysis methods on these benchmarks in terms of their recognition ability. Since these benchmarks are limited in terms of their

Sameer Singh; Maneesha Sharma

2001-01-01

449

Postmark: a new file system benchmark  

Microsoft Academic Search

Existing file system benchmarks are deficient in portraying performance in the ephemeral small-file regime used by Internet software, especially: electronicmail; netnews; and web-based commerce. PostMark is a new benchmark to measure performance for this class of application.In this paper, PostMark test results are presented and analyzed for both UNIX and Windows NT application servers. Network Appliance Filers (file server appliances)

J. Katcher

1997-01-01

450

Drill bit benchmarking improves drilling performance  

SciTech Connect

A practical method for standardizing drill bit selection reduced drilling costs by $5.5 million on the North Slope of Alaska. Shared Services Drilling (SSD), a consortium of BP Exploration Alaska and ARCO Alaska Inc., developed a benchmarking system that improved drilling performance across the Prudhoe Bay Unit (PBU). The process involved input from drill bit manufacturers, rig crews, and the operator. The paper discusses well configurations, bit standardization, benchmarking strategy, bit performance, PDC bits, and results.

Brown, L.A. Jr. [Hughes Christensen Co., The Woodlands, TX (United States); Stoltz, D.S. [ARCO Alaska Inc., Anchorage, AK (United States); Nims, D.G. [BP Exploration Alaska, Anchorage, AK (United States)

1997-06-02

451

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; 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

452

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

453

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

454

Combinational profiles of sequential benchmark circuits  

Microsoft Academic Search

A set of 31 digital sequential circuits described at the gate level is presented. These circuits extend the size and complexity of the ISCAS'85 set of combinational circuits and can serve as benchmarks for researchers interested in sequential test generation, scan-based test generation, and mixed sequential\\/scan-based test generation using partial scan techniques. Although all the benchmark circuits are sequential, synchronous,

Franc Brglez; David Bryan; K. Kozminski

1989-01-01

455

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

456

46 CFR 154.512 - Piping: Thermal isolation.  

Code of Federal Regulations, 2011 CFR

...Shipping 5 2011-10-01 2011-10-01 false Piping: Thermal isolation. 154.512 Section 154.512 Shipping ...Cargo and Process Piping Systems § 154.512 Piping: Thermal isolation. Low temperature piping must be thermally...

2011-10-01

457

46 CFR 154.512 - Piping: Thermal isolation.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Piping: Thermal isolation. 154.512 Section 154.512 Shipping COAST GUARD...and Process Piping Systems § 154.512 Piping: Thermal isolation. Low temperature piping must be thermally isolated...

2012-10-01

458

46 CFR 154.512 - Piping: Thermal isolation.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 2014-10-01 false Piping: Thermal isolation. 154.512 Section 154.512 Shipping COAST GUARD...and Process Piping Systems § 154.512 Piping: Thermal isolation. Low temperature piping must be thermally isolated...

2014-10-01

459

46 CFR 154.512 - Piping: Thermal isolation.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Piping: Thermal isolation. 154.512 Section 154.512 Shipping COAST GUARD...and Process Piping Systems § 154.512 Piping: Thermal isolation. Low temperature piping must be thermally isolated...

2013-10-01

460

46 CFR 154.522 - Materials for piping.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Materials for piping. 154.522 Section 154.522 Shipping...Construction and Equipment Cargo and Process Piping Systems § 154.522 Materials for piping. (a) The materials for piping...

2011-10-01

461

46 CFR 153.281 - Piping to independent tanks.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Piping to independent tanks. 153.281 Section...HAZARDOUS MATERIALS Design and Equipment Piping Systems and Cargo Handling Equipment § 153.281 Piping to independent tanks. Piping...

2012-10-01

462

46 CFR 154.522 - Materials for piping.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Materials for piping. 154.522 Section 154.522 Shipping...Construction and Equipment Cargo and Process Piping Systems § 154.522 Materials for piping. (a) The materials for piping...

2013-10-01

463

46 CFR 119.720 - Nonmetallic piping materials.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Nonmetallic piping materials. 119.720 Section 119.720...THAN 49 PASSENGERS MACHINERY INSTALLATION Piping Systems § 119.720 Nonmetallic piping materials. Nonmetallic piping...

2010-10-01

464

46 CFR 153.292 - Separation of piping systems.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Separation of piping systems. 153.292 Section 153...HAZARDOUS MATERIALS Design and Equipment Piping Systems and Cargo Handling Equipment § 153.292 Separation of piping systems. Cargo piping...

2013-10-01

465

46 CFR 154.548 - Cargo piping: Flow capacity.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Cargo piping: Flow capacity. 154.548 Section 154...Construction and Equipment Cargo and Process Piping Systems § 154.548 Cargo piping: Flow capacity. Piping with an excess...

2013-10-01

466

46 CFR 153.292 - Separation of piping systems.  

Code of Federal Regulations, 2011 CFR

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

2011-10-01

467

46 CFR 119.720 - Nonmetallic piping materials.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Nonmetallic piping materials. 119.720 Section 119.720...THAN 49 PASSENGERS MACHINERY INSTALLATION Piping Systems § 119.720 Nonmetallic piping materials. Nonmetallic piping...

2011-10-01

468

46 CFR 153.281 - Piping to independent tanks.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Piping to independent tanks. 153.281 Section...HAZARDOUS MATERIALS Design and Equipment Piping Systems and Cargo Handling Equipment § 153.281 Piping to independent tanks. Piping...

2011-10-01

469

46 CFR 154.548 - Cargo piping: Flow capacity.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Cargo piping: Flow capacity. 154.548 Section 154...Construction and Equipment Cargo and Process Piping Systems § 154.548 Cargo piping: Flow capacity. Piping with an excess...

2012-10-01

470

46 CFR 119.720 - Nonmetallic piping materials.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Nonmetallic piping materials. 119.720 Section 119.720...THAN 49 PASSENGERS MACHINERY INSTALLATION Piping Systems § 119.720 Nonmetallic piping materials. Nonmetallic piping...

2012-10-01

471

46 CFR 154.522 - Materials for piping.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Materials for piping. 154.522 Section 154.522 Shipping...Construction and Equipment Cargo and Process Piping Systems § 154.522 Materials for piping. (a) The materials for piping...

2010-10-01

472

46 CFR 153.292 - Separation of piping systems.  

Code of Federal Regulations, 2010 CFR

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

2010-10-01

473

46 CFR 95.16-60 - System piping installation testing.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 2014-10-01 false System piping installation testing. 95.16-60...Systems, Details § 95.16-60 System piping installation testing. (a) Halocarbon...conducted on halocarbon system discharge piping on completion of piping...

2014-10-01

474

46 CFR 154.522 - Materials for piping.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 2014-10-01 false Materials for piping. 154.522 Section 154.522 Shipping...Construction and Equipment Cargo and Process Piping Systems § 154.522 Materials for piping. (a) The materials for piping...

2014-10-01

475

46 CFR 119.720 - Nonmetallic piping materials.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Nonmetallic piping materials. 119.720 Section 119.720...THAN 49 PASSENGERS MACHINERY INSTALLATION Piping Systems § 119.720 Nonmetallic piping materials. Nonmetallic piping...

2013-10-01

476

46 CFR 95.16-60 - System piping installation testing.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false System piping installation testing. 95.16-60...Systems, Details § 95.16-60 System piping installation testing. (a) Halocarbon...conducted on halocarbon system discharge piping on completion of piping...

2012-10-01

477

46 CFR 153.281 - Piping to independent tanks.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 2014-10-01 false Piping to independent tanks. 153.281 Section...HAZARDOUS MATERIALS Design and Equipment Piping Systems and Cargo Handling Equipment § 153.281 Piping to independent tanks. Piping...

2014-10-01

478

46 CFR 153.281 - Piping to independent tanks.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Piping to independent tanks. 153.281 Section...HAZARDOUS MATERIALS Design and Equipment Piping Systems and Cargo Handling Equipment § 153.281 Piping to independent tanks. Piping...

2010-10-01

479

46 CFR 154.548 - Cargo piping: Flow capacity.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 2014-10-01 false Cargo piping: Flow capacity. 154.548 Section 154...Construction and Equipment Cargo and Process Piping Systems § 154.548 Cargo piping: Flow capacity. Piping with an excess...

2014-10-01

480

46 CFR 154.522 - Materials for piping.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Materials for piping. 154.522 Section 154.522 Shipping...Construction and Equipment Cargo and Process Piping Systems § 154.522 Materials for piping. (a) The materials for piping...

2012-10-01

481

46 CFR 153.292 - Separation of piping systems.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 false Separation of piping systems. 153.292 Section 153...HAZARDOUS MATERIALS Design and Equipment Piping Systems and Cargo Handling Equipment § 153.292 Separation of piping systems. Cargo piping...

2014-10-01

482

46 CFR 153.292 - Separation of piping systems.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Separation of piping systems. 153.292 Section 153...HAZARDOUS MATERIALS Design and Equipment Piping Systems and Cargo Handling Equipment § 153.292 Separation of piping systems. Cargo piping...

2012-10-01

483

46 CFR 154.548 - Cargo piping: Flow capacity.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Cargo piping: Flow capacity. 154.548 Section 154...Construction and Equipment Cargo and Process Piping Systems § 154.548 Cargo piping: Flow capacity. Piping with an excess...

2011-10-01

484

46 CFR 119.720 - Nonmetallic piping materials.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 2014-10-01 false Nonmetallic piping materials. 119.720 Section 119.720...THAN 49 PASSENGERS MACHINERY INSTALLATION Piping Systems § 119.720 Nonmetallic piping materials. Nonmetallic piping...

2014-10-01

485

46 CFR 153.281 - Piping to independent tanks.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Piping to independent tanks. 153.281 Section...HAZARDOUS MATERIALS Design and Equipment Piping Systems and Cargo Handling Equipment § 153.281 Piping to independent tanks. Piping...

2013-10-01

486

46 CFR 95.16-60 - System piping installation testing.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false System piping installation testing. 95.16-60...Systems, Details § 95.16-60 System piping installation testing. (a) Halocarbon...conducted on halocarbon system discharge piping on completion of piping...

2013-10-01

487

46 CFR 56.15-1 - Pipe joining fittings.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Pipe joining fittings. ...CONTINUED) MARINE ENGINEERING PIPING SYSTEMS AND...Fittings § 56.15-1 Pipe joining fittings. ...square inch gage. (c) Pipe joining fittings not...or produce a primary stress greater than...

2012-10-01

488

46 CFR 56.15-1 - Pipe joining fittings.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 false Pipe joining fittings. ...CONTINUED) MARINE ENGINEERING PIPING SYSTEMS AND...Fittings § 56.15-1 Pipe joining fittings. ...square inch gage. (c) Pipe joining fittings not...or produce a primary stress greater than...

2014-10-01

489

46 CFR 56.15-1 - Pipe joining fittings.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Pipe joining fittings. ...CONTINUED) MARINE ENGINEERING PIPING SYSTEMS AND...Fittings § 56.15-1 Pipe joining fittings. ...square inch gage. (c) Pipe joining fittings not...or produce a primary stress greater than...

2013-10-01

490

INTERIOR VIEW WITH LARGE PIPE CASTING MACHINE EXTRACTING A 48' ...  

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

INTERIOR VIEW WITH LARGE PIPE CASTING MACHINE EXTRACTING A 48' PIPE. - United States Pipe & Foundry Company Plant, Pipe Casting & Testing Area, 2023 St. Louis Avenue at I-20/59, Bessemer, Jefferson County, AL

491

INTERIOR VIEW WITH LARGE PIPE CASTING MACHINE CASTING A 48' ...  

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

INTERIOR VIEW WITH LARGE PIPE CASTING MACHINE CASTING A 48' PIPE. - United States Pipe & Foundry Company Plant, Pipe Casting & Testing Area, 2023 St. Louis Avenue at I-20/59, Bessemer, Jefferson County, AL

492

Action-Oriented Benchmarking: Concepts and Tools  

SciTech Connect

Most energy benchmarking tools provide static feedback on how one building compares to a larger set of loosely similar buildings, without providing information at the end-use level or on what can be done to reduce consumption, cost, or emissions. In this article--Part 1 of a two-part series--we describe an 'action-oriented benchmarking' approach, which extends whole-building energy benchmarking to include analysis of system and component energy use metrics and features. Action-oriented benchmarking thereby allows users to generate more meaningful metrics and to identify, screen and prioritize potential efficiency improvements. This opportunity assessment process can then be used to inform and optimize a full-scale audit or commissioning process. We introduce a new web-based action-oriented benchmarking system and associated software tool-EnergyIQ. The benchmarking methods, visualizations, and user interface design are informed by an end-user needs assessment survey and best-practice guidelines from ASHRAE.

California Energy Commission; Mathew, Paul; Mills, Evan; Mathew, Paul; Piette, Mary Ann; Bourassa, Norman; Brook, Martha

2008-02-13

493

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

494

Development of gprs-based leak detection system for pipe pushing crossing part of nature gas pipeline  

Microsoft Academic Search

There would be a sealed space, called culvert box, between the nature gas pipeline and the concrete pipe when the nature gas pipeline crossing highways, railways and rivers using the trenchless pipe pushing technology. To deal with the problem of leak detection and monitoring for these culvert boxes, which were located in the field and scattered, a GPRS-based (GPRS: general

Fujun Liu; Shuai Kong; Zhangwei Ling; Mulin Zheng; Yueqiang Qian

2011-01-01

495

46 CFR 119.455 - Fuel piping.  

Code of Federal Regulations, 2010 CFR

...such as seamless steel pipe or tubing...fuel piping of aluminum is acceptable on aluminum hull vessels provided...protect against corrosion. Where passing...bowls of other than steel construction must...bowls of other than steel construction...

2010-10-01

496

Polyethylene Encasement for Cast-Iron Pipe  

Microsoft Academic Search

External corrosion of buried iron pipe can occur if an area's soil is corrosive. To help protect pipe against electrolytic current, the use of polyethylene encasement is recommended. Standard specifications developed for this product are reviewed in the following.

Walter Amory

1976-01-01

497

Duality of antidiagonals and pipe dreams  

Microsoft Academic Search

Weighted enumeration of reduced pipe dreams (or rc-graphs) results in a combinatorial expression for Schubert polynomials. The duality between the set of reduced pipe dreams and certain antidiagonals has important geometric implications [A. Knutson and E. Miller, Gr\\\\\\

Ning Jia; Ezra Miller

2007-01-01

498