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Fire Doors for Noncoal Mines

Description: Report issued by the U.S. Bureau of Mines discussing the development and use of fire doors in non-coal mines. As stated in the abstract, "this report discusses current fire-door technology in the context of the underground mine environment and the design, fabrication, lab testing, and in-mine field testing of a mine-worthy fire door" (p. 1). This report includes tables, illustrations, and photographs.
Date: 1987
Creator: Bickel, Kenneth L. & Pomroy, William H.
Partner: UNT Libraries Government Documents Department
open access

A Review of Two-Phase Flow-Induced Vibration

Description: Two-phase flow exists in many shell-and-tube heat exchangers and power generation components. The flowing fluid is a source of energy that can induce small-amplitude subcritical oscillations and large-amplitude dynamic instabilities. In fact, many practical system components have experienced excessive flow-induced vibrations. To prevent unacceptable flow-induced vibration, we must understand excitation mechanisms, develop analytical and experimental techniques, and provide reliable design guide… more
Date: August 1987
Creator: Chen, Shoei-Sheng
Partner: UNT Libraries Government Documents Department
open access

Analysis of Proposed Gamma-Ray Detection System for the Monitoring of Core Water Inventory in a Pressurized Water Reactor

Description: An initial study has been performed of the feasibility of employing an axial array of gamma detectors located outside the pressure vessel to monitor the coolant in a PWR. A one-dimensional transport analysis model is developed for the LOFT research reactor and for a mock-PWR geometry. The gamma detector response to coolant voiding in the core and down-comer has been determined for both geometries. The effects of various conditions (for example, time after shutdown, materials in the transport pa… more
Date: December 1987
Creator: Markoff, Diane Melanie
Partner: UNT Libraries Government Documents Department
open access

REDUCE-Aided Study of a Problem in Hermitian Matrix Theory

Description: Let A be any n x n positive definite matrix and B any n x n non-negative definite matrix. In an earlier paper we showed that for each n there is a real number t/sub n/> 2 such that if t <t/sub n/ then the solution X of the matrix equation A²X + XA² + tAXA = B is non-negative definite. For n = 2, t₂ = infinity and for n = 3, t₃ = 8. In this report we show that t₄ = 4, t₅ <3.02048507 and t₆ <2.62120330.
Date: July 1987
Creator: Kwong, Man Kam
Partner: UNT Libraries Government Documents Department
open access

A Review of Parameterizations of Microphysical Processes in Clouds for Application in Models of Regional Atmospheric Deposition

Description: The literature on parameterizations of cloud microphysical processes was reviewed to examine the theoretical bases of those parameterizations and to evaluate their applicability to regional models. New parameterizations were produced by multiple regression upon the solution fields derived from simulations of a cloud model incorporating sophisticated microphysics. The currently available rates for cloud microphysical interactions were generally derived under the assumption that the size distribu… more
Date: August 1987
Creator: Lee, L. Y. & Hong, M. S.
Partner: UNT Libraries Government Documents Department
open access

Post-Test Analyses of Aqueous Batteries Developed for Electric Propulsion : Summary Report for January 1985-September 1986

Description: This document is a summary of the activities conducted on post-test examination of aqueous electric-vehicle batteries from January 1985 to September 1986. The post-test analyses were conducted to determine the causes of performance degradation (e.g., capacity decline, power loss, self-discharge) in lead-acid and nickel/iron batteries. For the lead-acid batteries, the primary causes of capacity decline were generally found to be morphological changes in the positive active material, corrosion of… more
Date: July 1987
Creator: Miller, J. F.; Marr, J. J. & Smaga, J. A.
Partner: UNT Libraries Government Documents Department
open access

An Approach to Implementing State Space Searches on Heterogeneous Systems of Multiprocessors

Description: We report on experiments run on a set of shared-memory multiprocessors. Our goal was to demonstrate that one could conveniently utilize a set of shared-memory multiprocessors cooperatively working on typical state-space searches. We utilized a technology for writing portable code for multiprocessors, coded three depth-first state-space searches, and ran them on a set of multiprocessors. The final problem used substantial resources (over 65 hours on a single processor) and was successfully distr… more
Date: September 1987
Creator: Glickfeld, Barney & Overbeek, Ross A.
Partner: UNT Libraries Government Documents Department
open access

A Review and Analysis of Fortran 8x

Description: The ANSI Standards Subcommittee X3J3 on Fortran has recently completed a draft proposed standard for the Fortran programming language. The draft proposed standard, known informally as Fortran 8x, is a revision of the current standard X3.9-1978, known informally as Fortran 77. This report is a review of Fortran 8x and consists of a series of six articles. The first article gives a general overview of Fortran 8x. The next three articles give brief discussions of the array facilities; the enhanced… more
Date: October 1987
Creator: Smith, Brian T.
Partner: UNT Libraries Government Documents Department
open access

Review of the Analyses of the Doppler-Effect Measurements in SEFOR (Southwest Experimental Fast Oxide Reactor)

Description: The SEFOR experimental results and the three original analyses are reviewed and discussed. The emphasis of the review is placed on aspects that are pertinent to a possible modern re-analysis of the experimental results. Looking at the analysis results in terms of zero and first order effects shows that the zero order effects, the Doppler constant of the two SEFOR cores, are obtained by the three analyses in satisfactory agreement. But the first order effects, but temperature variation of this D… more
Date: July 1987
Creator: Ott, Karl O.
Partner: UNT Libraries Government Documents Department
open access

One-Dimensional Leakage-Flow Vibration Instabilities

Description: Simple boundary conditions, pressure losses, and channel geometries necessary for the unstable, rigid-body translational vibrations of the wall of one-dimensional leakage-flow channel are identified. General expressions for the flow damping and stiffness forces acting on the vibrating channel wall are derived and specific results are given for channels with wall friction, point pressure losses, sharp-edged constrictions, and diverging or converging widths. The minimum conditions necessary for d… more
Date: September 1987
Creator: Mulcahy, T. M.
Partner: UNT Libraries Government Documents Department
open access

Application of a Multigrid Method to a Buoyancy-Induced Flow Problem

Description: The numerical prediction of buoyancy-induced flows provides special difficulties for standard numerical techniques associated with velocity-buoyancy coupling. We present a multigrid algorithm based upon a novel relaxation scheme that handles this coupling correctly. Numerical experiments have been performed that show that this approach is reasonably efficient and robust for a range of Rayleigh numbers and a variety of cycling strategies.
Date: October 1987
Creator: Thompson, C. P.; Leaf, G. K. & Vanka, S. P.
Partner: UNT Libraries Government Documents Department
open access

Screening and Degradation Tests of Linear-Polymer Additives for District Heating Applications

Description: In closed-loop district heating and cooling (DHC) systems, the addition of a friction-reducing additive to the working fluid conveying energy between the energy sources and end users would allow increased load-handling capability (in an existing system) or the use of much smaller pipes and/or pumps (in a new system). As the first step in identifying friction-reducing additives that have a reasonable lifetime at DHC temperatures, two high-molecular-weight linear-polymer additives have been teste… more
Date: December 1987
Creator: Choi, U. S.; Cho, Young I. & Kasza, Kenneth Edmund
Partner: UNT Libraries Government Documents Department
open access

Weight Losses of Marble and Limestone Briquettes Exposed to Outdoor Environments in the Eastern United States

Description: Weight losses of marble and limestone samples exposed to outdoor environments at field sites in the eastern United States have been monitored in studies initiated in 1984. The procedures are described, and the results are tabulated and discussed. A rate of marble loss approximately equivalent to 16 micrometers of surface recession per year was found in North Carolina, and losses of this order were also observed in New Jersey, New York, and Washington, DC. Limestone weight losses were much highe… more
Date: August 1987
Creator: Youngdahl, C. A.
Partner: UNT Libraries Government Documents Department
open access

Toolpack/1 Release 2 : Introductory Guide

Description: This guide introduces Toolpack/1 Release 2, the second public release of Toolpack/1, an integrated suite of Fortran 77 software tools. The guide describes the background to the Toolpack project and explains the basic concepts and terms involved in the design and use of the tool suite. It also summarizes the facilities available in the second release and refers readers to other Toolpack/1 documentation for more detailed discussion. This guide should be regarded as essential preliminary reading f… more
Date: March 1987
Creator: Cowell, Wayne R.; Hague, S. J. & Iles, R. M. J.
Partner: UNT Libraries Government Documents Department
open access

Sodium Waste Technology : a Summary Report

Description: The Sodium Waste Technology (SWT) Program was established to resolve long-standing issues regarding disposal of sodium-bearing waste and equipment. Comprehensive SWT research programs investigated a variety of approaches for either removing sodium from sodium-bearing items, or disposal of items containing sodium residuals. The most successful of these programs was the design, test, and the production operation of the Sodium Process Demonstration Facility at ANL-W. The technology used was a seri… more
Date: January 1987
Creator: Abrams, C. S. & Witbeck, L. C.
Partner: UNT Libraries Government Documents Department
open access

Measurement of Stibine and Arsine Generation from the Exide 3100-Ah Lead-Acid Module

Description: Stibine and arsine evolution from lead-acid cells in a 36-kWh Exide load-leveling module was measured as this module approached 1900 cycles of operation. A specially prepared gas-collection apparatus enabled us to determine the maximum and average rates for evolution of both toxic hydrides. Hydride generation began once the cell voltage exceeded 2.4 V. The maximum rate for arsine occurred just above 2.5 V and consistently preceded the peak rate for stibine for each sampled cell. When adjusted f… more
Date: January 1987
Creator: Marr, J. J. & Smaga, J. A.
Partner: UNT Libraries Government Documents Department
open access

Final Report for the Light Water Breeder Reactor Proof-of-Breeding Analytical Support Project

Description: The technology of breeding uranium-233 from thorium-232 in a light water reactor is being developed and evaluated by the Westinghouse Bettis Atomic Power Laboratory (BAPL) through operation and examination of the Shippingport Light Water Breeder Reactor (LWBR). Bettis is determining the end-of-life (EOL) inventory of fissile uranium in the LWBR core by nondestructive assay of a statistical sample comprising approximately 500 EOL fuel rods. This determination is being made with an irradiated-fue… more
Date: May 1987
Creator: Graczyk, D. G.; Hoh, J. C.; Martino, F. J.; Nelson, R. E.; Osudar, John & Levitz, Norman M.
Partner: UNT Libraries Government Documents Department
open access

A Theory of Program Correctness, and Algorithms for Proofs

Description: A model of program correctness is given where a problem domain is defined by its language, variable names, and an abstract machine defining the semantics of the language. The set of all computations in this domain is shown to be a semigroup. A corresponding statement is true of a more general programming language. A program P in the general language is an element of the semigroup. If P performs computations in some domain, a connection can be established between P and the semigroup of computati… more
Date: January 1987
Creator: Gabriel, John R.; Chapman, Richard O. & Kljaich, J. L.
Partner: UNT Libraries Government Documents Department
open access

²³⁵U(n,f), ²³⁸U(n, gamma), ²³⁸U(n,f), ²³⁹Pu(n,f) Reaction Rate Measurement Calibrations at ZPPR

Description: New reference deposits for uranium-235, plutonium-239 and uranium-238 have been established with mass uncertainties of <0.2%. These new deposits replace the older reference deposits which were used during the last 17 years and improve the uncertainty of reaction rate measurements due to reference mass uncertainties by about a factor of 6. Measurements of the fission fragment absorption in 2 pi and low-geometry count rates. Two measurements of the uranium-238 capture rate in depleted uranium sam… more
Date: January 1987
Creator: Poenitz, W. P.; Maddison, D. W.; Gasidlo, J. M.; Carpenter, S.G. & Armani, R. J.
Partner: UNT Libraries Government Documents Department
open access

Investigation of Primary Li-Si/FeS2 Cells

Description: The factors that limit the performance of thermally activated Li-Si/FeS2 batteries were defined through the use of electrochemical characterization tests and post-test examinations. For the characterization tests, 82 individual cells were instrumented with multiple voltage sensors and discharged under isothermal and isobaric conditions. The voltage data for the sensors were recorded to determine the ohmic and electrochemical impedances of each cell component at different levels of discharge. Th… more
Date: April 1987
Creator: Redey, L.; Smaga, J. A.; Battles, J. E. & Guidotti, Ronald
Partner: UNT Libraries Government Documents Department
open access

Beyond "'Speedup": Performance Analysis of Parallel Programs

Description: This paper addresses the problem of measuring and analyzing the performance of fine-grained parallel programs running on shared-memory multiprocessors. Such processors use locking (either directly in the application program, or indirectly in a subroutine library or the operating system) to serialize accesses to global variables. Given sufficiently high rates of locking, the chief factor preventing linear speedup (besides lack of adequate inherent parallelism in the application) is lock contenti… more
Date: February 1987
Creator: Dritz, Kenneth W. & Boyle, James M.
Partner: UNT Libraries Government Documents Department
open access

Site Surveillance and Maintenance Program for Palos Park : Report for 1986

Description: The results of the environmental monitoring program conducted at Site A/Plot M in the Palos Park Forest Preserve area for CY 1986 are presented. The monitoring program is the ongoing remedial action that resulted from the original radiological characterization of the site. The program consists of sample collection and analysis of air, surface and subsurface water, and bottom sediment to determine the migration pathway of water from the burial ground (Plot M) to hand-operated picnic wells, estab… more
Date: April 1987
Creator: Golchert, N. W. & Sedlet, J.
Partner: UNT Libraries Government Documents Department
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