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DDES and IDDES of tandem cylinders.

Description: The paper presents an overview of the authors contribution to the BANC-I Workshop on the flow past tandem cylinders (Category 2). It includes an outline of the simulation approaches, numerics, and grid used, the major results of the simulations, their comparison with available experimental data, and some preliminary conclusions. The effect of varying the spanwise period in the simulations is strong for some quantities, and not others.
Date: September 9, 2010
Creator: Balakrishnan, R.; Garbaruk, A.; Shur, M.; Strelets, M.; Spalart, P.; Russia, New Technologies and Services - et al.
Partner: UNT Libraries Government Documents Department

Thermal ablation of plasma-facing surfaces in tokamak disruptions: Sensitivity to particle kinetic energy

Description: Ablation damage to solid targets with high heat flux impulses is generally greater high-energy electron beam heat sources compared to low-energy plasma guns. This sensitivity to incoming particle kinetic energy is explored with computer modelling; a fast-running routine (DESIRE) is developed for initial scoping analysis and is found to be in reasonable agreement with several experiments on graphite and tungsten targets. If tokamak disruptions are characterized by particle energies less than {approximately}1 keV, then we expect plasma guns are a better analogue than electron beams for simulating disruption behavior and testing candidate plasma-facing materials.
Date: February 1, 1996
Creator: Ehst, D.A. & Hassanein, A.
Partner: UNT Libraries Government Documents Department

DONIO: Distributed Object Network I/O Library

Description: This report describes the use and implementation of DONIO (Distributed Object Network I/O), a library of routines that provide fast file I/O capabilities in the Intel iPSC/860 and Paragon distributed memory parallel environments. DONIO caches a copy of the file in memory distributed across all processors. Disk I/O routines (such as read, write, and lseek) are replaced by calls to DONIO routines, which translate these operations into message communication to update the cached data. Experiments on the Intel Paragon show that the cost of concurrent disk I/O using DONIO for large files can be 15-30 times smaller than using standard disk I/O.
Date: January 1, 1994
Creator: D'Azevedo, E.F.
Partner: UNT Libraries Government Documents Department

DOSFAC2 user`s guide

Description: This document describes the DOSFAC2 code, which is used for generating dose-to-source conversion factors for the MACCS2 code. DOSFAC2 is a revised and updated version of the DOSFAC code that was distributed with version 1.5.11 of the MACCS code. included are (1) an overview and background of DOSFAC2, (2) a summary of two new functional capabilities, and (3) a user`s guide. 20 refs., 5 tabs.
Date: December 1, 1997
Creator: Young, M.L. & Chanin, D.
Partner: UNT Libraries Government Documents Department

Energy performance of evacuated glazings in residential buildings

Description: This paper presents the results of a study investigating the energy performance of evacuated glazings or glazings which maintain a vacuum between two panes of glass. Their performance is determined by comparing results to prototype highly insulated superwindows as well as a more conventional insulating glass unit with a low-E coating and argon gas fill. The authors used the DOE-2.1E energy analysis simulation program to analyze the annual and hourly heating energy use due to the windows of a prototypical single-story house located in Madison, Wisconsin. Cooling energy performance was also investigated. The results show that for highly insulating windows, the solar heat gain coefficient is as important as the window`s U-factor in determining heating performance for window orientations facing west-south-east. For other orientations in which there is not much direct solar radiation, the window`s U-factor primarily governs performance. The vacuum glazings had lower heating requirements than the superwindows for most window orientations. The conventional low-E window outperformed the superwindows for southwest-south-southeast orientations. These performance differences are directly related to the solar heat gain coefficients of the various windows analyzed. The cooling performance of the windows was inversely related to the heating performance. The lower solar heat gain coefficients of the superwindows resulted in the best cooling performance. However, the authors were able to mitigate the cooling differences of the windows by using an interior shading device that reduced the amount of solar gain at appropriate times.
Date: October 1, 1996
Creator: Sullivan, R.; Beck, F.; Arasteh, D. & Selkowitz, S.
Partner: UNT Libraries Government Documents Department

DSDP3: dual scaling algorithm for general positive semidefinite programming.

Description: We implement a dual scaling algorithm for positive semidefinite programming to handle a broader class of problems than could be solved with previous implementations of the algorithm. With appropriate representations of constraint matrices, we can solve general semidefinite programs and still exploit the structure of large-scale combinatorial optimization problems. Computational results show that our preliminary implementation is competitive with primal-dual solvers on many problems requiring moderate precision in the solution and is superior to primal-dual solvers for several types of problems.
Date: March 19, 2001
Creator: Benson, S.J. & Ye, Y.
Partner: UNT Libraries Government Documents Department

Diffuse II -- A hydrogen isotope diffusion and trapping simulation program upgrade

Description: Diffuse is a finite difference computer program which may be used to calculate the one-dimensional diffusion and trapping of atoms in a host material under general initial, source, and boundary conditions. Diffuse was originally written in Fortran prior to 1980, and rewritten in 1983 in order to run on the Sandia Cray computers in use through the early 1990's. When the mainframe computers were retired, the Gas Transfer System (GM) Development Department ported the code to the PC platform, where it ran as a simple console application. All graphical output was lost during this port. GM code developers have completed an upgrade that provides a Windows 95/NT Diffuse application and restores all of the original graphical output. This upgrade is called Diffuse II version 1.0. This report serves both as a users manual for Diffuse II version 1.0 and as a general software development reference.
Date: November 1, 1998
Creator: Hardwick, M. F. & Robinson, S. L.
Partner: UNT Libraries Government Documents Department

Annual performance prediction for off-axis aligned Lugo heliostats at Solar Two

Description: The DELSOL computer code was used to model the annual Performance for numerous off-axis alignments of the Lugo heliostats located at the Solar Two site in Dagget, California. Recommended canting times are presented for the Lugo heliostats based upon their location in the field. Predicted annual performance of an off-axis alignment was actually higher than for on-axis alignment in some cases, and approximately equal if the recommended times are used. The annual performances of Solar One heliostats located nearby were also calculated, and illustrated the poorer performance expected of the Lugo heliostats.
Date: February 1, 1996
Creator: Jones, S.A.
Partner: UNT Libraries Government Documents Department

Results after ten years of field testing low-level radioactive waste forms using lysimeters

Description: The Field Lysimeter Investigations: Low-Level Waste Data Base Development Program is obtaining information on the performance of radioactive waste forms. Ion-exchange resins from a commercial nuclear power station were solidified into waste forms using portland cement and vinyl esterstyrene. These waste forms are being tested to: (a) obtain information on performance of waste forms in typical disposal environments, (b) compare field results with bench leach studies, (c) develop a low-level waste data base for use in performance assessment source term calculations, and (d) apply the DUST computer code to compare predicted cumulative release to actual field data. The program, funded by the Nuclear Regulatory Commission (NRC), includes observed radionuclide releases from waste forms in field lysimeters. The purpose of this paper is to present the experimental results of two lysimeter arrays over 10 years of operation, and to compare those results to bench test results and to DUST code predicted releases. Further analysis of soil cores taken to define the observed upward migration of radionuclides in one lysimeter is also presented.
Date: December 1, 1995
Creator: McConnell, J.W. Jr.; Rogers, R.D.; Jastrow, J.D.; Sanford, W.E.; Larsen, I.L. & Sullivan, T.M.
Partner: UNT Libraries Government Documents Department


Description: We extended the ability of DEPOL [1] to calculate coupled spin resonances and used it to determine the location and strength of both intrinsic and coupled spin resonances in RHIC. In particular we are interested in the full resonance structure with solenoidal elements turned on and with quadrupole rolls[2].
Date: June 18, 2001
Partner: UNT Libraries Government Documents Department

DeepNet: An Ultrafast Neural Learning Code for Seismic Imaging

Description: A feed-forward multilayer neural net is trained to learn the correspondence between seismic data and well logs. The introduction of a virtual input layer, connected to the nominal input layer through a special nonlinear transfer function, enables ultrafast (single iteration), near-optimal training of the net using numerical algebraic techniques. A unique computer code, named DeepNet, has been developed, that has achieved, in actual field demonstrations, results unattainable to date with industry standard tools.
Date: July 10, 1999
Creator: Barhen, J.; Protopopescu, V. & Reister, D.
Partner: UNT Libraries Government Documents Department

PDF Requirements Linking

Description: This report describes the PDF Object Linking Extension (POLE) and how it came about. POLE is an extension of an existing DXL script called Outdoors that provides a linking mechanism to files outside of DOORS. Our modifications expand the script's capabilities to link to bookmarks within PDF documents. PDF linking allows for traceability to be maintained between DOORS objects and the requirements within PDF files.
Date: July 1, 2002
Partner: UNT Libraries Government Documents Department

What Can DMIS 5.2 Do For You?

Description: The Dimensional Measuring Interface Standard (DMIS) is the first data interoperability protocol standard created specifically for dimensional metrology. DMIS applications are multi-facetted. The standard can behave as a coordinate metrology language to execute measurement part programs, or it can be used as a neutral data exchange mechanism for part programs and measurement results. DMIS is full featured and has many successful implementations. It also has a strong reputation as a progressive standard, one that has been responsive to user needs and technology advances. It is maintained and improved upon by a volunteer committee, the DMIS Standards Committee (DSC), under the auspices of the Dimensional Metrology Standards Consortium (DMSC Inc.). DMIS has progressed as its eighth version and its sixth as a national and/or international standard. Some notable advances of DMIS have included: • support for thin-walled (i.e., sheet-metal) measurements • alignment with American and International tolerancing standards • complete suite of measure features • harmonization with complementary standards and specifications • extension of additional sensors and scanning processes • introduction of measurement uncertainty computations • tighter CAD associativity • enhancements for multi-axis scanning • provisioning for functional subsets (application profiles) • progression of conformance class validations • designation of key characteristics with criticality designators • removal of ambiguities and syntactic limitations • clarification through additional diagrams and code fragments • resolution to over 600 standard improvement requests
Date: August 20, 2009
Creator: Brown, Curtis W.
Partner: UNT Libraries Government Documents Department

Analysis of the Argonne distance tabletop exercise method.

Description: The purpose of this report is to summarize and evaluate the Argonne Distance Tabletop Exercise (DISTEX) method. DISTEX is intended to facilitate multi-organization, multi-objective tabletop emergency response exercises that permit players to participate from their own facility's incident command center. This report is based on experience during its first use during the FluNami 2007 exercise, which took place from September 19-October 17, 2007. FluNami 2007 exercised the response of local public health officials and hospitals to a hypothetical pandemic flu outbreak. The underlying purpose of the DISTEX method is to make tabletop exercising more effective and more convenient for playing organizations. It combines elements of traditional tabletop exercising, such as scenario discussions and scenario injects, with distance learning technologies. This distance-learning approach also allows playing organizations to include a broader range of staff in the exercise. An average of 81.25 persons participated in each weekly webcast session from all playing organizations combined. The DISTEX method required development of several components. The exercise objectives were based on the U.S. Department of Homeland Security's Target Capabilities List. The ten playing organizations included four public health departments and six hospitals in the Chicago area. An extent-of-play agreement identified the objectives applicable to each organization. A scenario was developed to drive the exercise over its five-week life. Weekly problem-solving task sets were designed to address objectives that could not be addressed fully during webcast sessions, as well as to involve additional playing organization staff. Injects were developed to drive play between webcast sessions, and, in some cases, featured mock media stories based in part on player actions as identified from the problem-solving tasks. The weekly 90-minute webcast sessions were discussions among the playing organizations that were moderated by a highly-qualified public health physician, who reviewed key scenario developments and player actions, as well as ...
Date: February 14, 2008
Creator: Tanzman, E. A.; Nieves, L. A. & Sciences, Decision and Information
Partner: UNT Libraries Government Documents Department

Experiences using DAKOTA stochastic expansion methods in computational simulations.

Description: Uncertainty quantification (UQ) methods bring rigorous statistical connections to the analysis of computational and experiment data, and provide a basis for probabilistically assessing margins associated with safety and reliability. The DAKOTA toolkit developed at Sandia National Laboratories implements a number of UQ methods, which are being increasingly adopted by modeling and simulation teams to facilitate these analyses. This report disseminates results as to the performance of DAKOTA's stochastic expansion methods for UQ on a representative application. Our results provide a number of insights that may be of interest to future users of these methods, including the behavior of the methods in estimating responses at varying probability levels, and the expansion levels for the methodologies that may be needed to achieve convergence.
Date: January 1, 2012
Creator: Templeton, Jeremy Alan & Ruthruff, Joseph R.
Partner: UNT Libraries Government Documents Department

Modeling the effects of reflective roofing

Description: Roofing materials which are highly reflective to sunlight are currently being developed. Reflective roofing is an effective summertime energy saver in warm and sunny climates. It has been demonstrated to save up to 40% of the energy needed to cool a building during the summer months. Buildings without air conditioning can reduce their indoor temperatures and improve occupant comfort during the summer if highly reflective roofing materials are used. But there are questions about the tradeoff between summer energy savings and extra wintertime energy use due to reduced heat collection by the roof. These questions are being answered by simulating buildings in various climates using the DOE-2 program (version 2.1E). Unfortunately, DOE-2 does not accurately model radiative, convective and conductive processes in the roof-attic. Radiative heat transfer from the underside of a reflective roof is much smaller than that of a roof which absorbs heat from sunlight, and must be accounted for in the building energy model. Convection correlations for the attic and the roof surface must be fine tuned. An equation to model the insulation`s conductivity dependence on temperature must also be added. A function was written to incorporate the attic heat transfer processes into the DOE-2 building energy simulation. This function adds radiative, convective and conductive equations to the energy balance of the roof. Results of the enhanced DOE-2 model were compared to measured data collected from a school bungalow in a Sacramento Municipal Utility District monitoring project, with particular attention paid to the year-round energy effects.
Date: August 1, 1996
Creator: Gartland, L.M.; Konopacki, S.J. & Akbari, H.
Partner: UNT Libraries Government Documents Department

Realization rates of the National Energy Audit

Description: Engineering estimates of savings resulting from installation of energy conservation measures in homes are often greater than the savings actually realized. A brief review of prior studies of realization rates prefaces this study of rates from an engineering audit tool, NEAT, (developed for the Department of Energy`s Low-Income Weatherization Assistance Program) used in a New York state utility`s low-income program. Estimates of metered and predicted savings are compared for 49 homes taken from a data base of homes that participated in the first year of the utility`s program. Average realization rates ranging from 57% to 69% result, depending on the data quality. Detailed examinations of two houses using an alternate engineering method, the DOE-2 computer program (considered an industry standard), seem to indicate that the low realization rates mainly result from factors other than inaccuracies in the audit`s internal algorithms. Causes of the low realization rates are examined, showing that the strongest single factor linked to the low rates in this study is the use of secondary heating fuels that supplement the primary heating fuel. This study, like the other similar studies, concludes that engineering estimates are valuable tools in determining ranked lists of cost-effective weatherization measures, but may not be accurate substitutes for measured results in evaluating program performance.
Date: November 1, 1998
Creator: Berry, L.G. & Gettings, M.B.
Partner: UNT Libraries Government Documents Department

DEWFALL validation experiment designs

Description: Three experiments are proposed as tests to validate the DEWFALL analysis model for the large vessel project. This document is a very brief record of the techniques and test designs that could be used for validation of the model. Processes of the model which require validation include: (1) vaporization and recondensation of the vessel wall material due to energy transfer from the source, (2) melt and refreeze of vessel wall material, and (3) condensation and solidification of the source material. A methodology was developed to analyze the maximum thickness of material melted and vaporized with given experimental configurations and initial energies. DEWFALL reference calculations are included in an appendix to the document. 2 refs., 3 figs., 3 tabs.
Date: September 30, 1989
Creator: Lowry, B. & Walsh, B.
Partner: UNT Libraries Government Documents Department

DORT and TORT workshop -- Outline for presentation for splicing with TORSED and TORSET

Description: This paper addresses the problem of solving a problem which is larger than can be accommodated by the computer system at your disposal. This can result from two constrains: (1) The available memory of the machine is too small to contain the problem. (2) Individual files may be too large to store on-line. It also addresses the problem of what to do when you want to alter only a subset of a solution space of a larger problem and don`t want to rerun the entire problem. These problems can be solved by splicing with TORSED AND TORSET. If the basic shape of your problem is cylindrical and azimuthally uniform, with only a small region of three-dimensionality, then the best splicing method is the TORSED -- DORT to TORT splice. However, if there is no part of the problem which is azimuthally constant, then one might want to consider a TORT to TORT splice. Both methods are discussed here.
Date: April 1, 1998
Creator: Barnett, A.
Partner: UNT Libraries Government Documents Department