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The Implementation of Industry Foundation Classes in Simulation Tools for the Building Industry

Description: Industry Foundation Classes (IFC) provide an environment of interoperability among IFC-compliant software applications in the architecture, engineering, construction, and facilities management (AEC/FM) industry. They allow building simulation software to automatically acquire building geometry and other building data from project models created with IFC compliant CAD software. They also facilitate direct exchange of input and output data with other simulation software. This paper discusses how … more
Date: June 1, 1997
Creator: Bazjanac, Vladimir & Crawley, Drury B.
Partner: UNT Libraries Government Documents Department
open access

Rayleigh-taylor instability growth experiments in a cylindrically convergent geometry

Description: Convergent geometry Rayleigh-Taylor experiments have been performed with a 122-point detonation initiation system on cylinders having sinusoidal perturbations on the outer surface ranging from mode-6 to mode-36. Experiments were performed with various perturbation mode numbers, perturbation amplitudes, and ring accelerations. Feedthrough perturbation growth on the inner surface was observed in several experiments, and in one experiment the feed through perturbation underwent a phase inversion. … more
Date: June 11, 1997
Creator: Weir, S. T., LLNL
Partner: UNT Libraries Government Documents Department
open access

Crystallization pathway in the bulk metallic glass Zr{sub 41.2}Ti{sub 13.8}Cu{sub 12.5}Ni{sub 10}Be{sub 22.5}.

Description: A new family of multicomponent metallic alloys exhibits an excellent glass forming ability at moderate cooling rates of about 10K/s and a wide supercooled liquid region. These glasses are eutectic or nearly eutectic, thus far away from the compositions of competing crystalline phases. The nucleation of crystals from the homogeneous amorphous phase requires large thermally activated composition fluctuations for which the time scale is relatively long, even in the supercooled liquid. In the Zr{su… more
Date: June 24, 1997
Creator: Geyer, U.; Johnson, W. L.; Schneider, S. & Thiyagarajan, P.
Partner: UNT Libraries Government Documents Department
open access

Dispersion Relationship for Solid State Instability Growth and Sensitivity to Equation of State

Description: We have derived an approximate analytical dispersion relation for solid state instability growth following the method of Mikaelian. I He starts with the general eigenvalue equation for the velocity of a perturbation on a finite-thickness fluid layer with surface tension and viscosity, and derives an exact solution numerically from det(M)=0, where M is an 8x8 matrix. He then derives an approximate solution analytically by substituting the inviscid eigenfunctions into the exact eigenvalue equatio… more
Date: June 1, 1997
Creator: Colvin, J. D.; Wiley, L. G.; Chandler, E. A.; Remington, B. A. & Kalantar, D. H.
Partner: UNT Libraries Government Documents Department
open access

Plasma mirrors for short pulse lasers

Description: We show experimentally and theoretically that plasmas created by a sufficiently (1014 1015 2 short (<500 fs) intense W/cm ) laser pulse on the surface of dielectric material act as nearly perfect mirrors: reflecting p to 90% of the incident radiation with a wavefront quality equal to that of the initial solid surface.
Date: June 11, 1997
Creator: Yanovsky, V. P.; Perry, M. D.; Brown, C. G.; Feit, M. D. & Rubenchik, A.
Partner: UNT Libraries Government Documents Department
open access

Intermediate-Range Order in Simple Metal-Phosphate Glasses: The Effect of Metal Cations on the Phosphate Anion Distribution

Description: The technique of high-performance liquid chromatography (HPLC) has been used to probe the phosphate anion distribution in a variety of metal phosphate glasses including glasses made with trivalent metal cations (Al, In, Ga, La). The composition of each glass was chosen so that the average phosphate chain length was between 2 and 4 PO{sub 4} tetrahedra. The widths of the resulting phosphate anion distributions were determined directly from an analysis of the HPLC chromatograms. Literature values… more
Date: June 1, 1997
Creator: Sales, B. C.; Boatner, L. A. & Ramey, J. O.
Partner: UNT Libraries Government Documents Department
open access

Design and implementation of a slow orbit control package at Thomas Jefferson National Accelerator Facility

Description: The authors describe the design and implementation of a C++ client/server based slow orbit and energy control package based on the CDEV software control bus. Several client applications are described and operational experience is given.
Date: June 1, 1997
Creator: van Zeijts, J.; Witherspoon, S. & Watson, W. A.
Partner: UNT Libraries Government Documents Department
open access

Materials and process development for the monolithic interconnected module (MIM) InGaAs/InP TPV cells

Description: Four major components of a thermophotovoltaic (TPV) energy conversion system are a heat source, a graybody or a selective emitter, spectrum shaping elements such as filters, and photovoltaic (PV) cells. One approach to achieving a high voltage/low current configuration is to fabricate a device, where small area PV cells are monolithically series connected. The authors have termed this device a monolithic interconnected module (MIM). A MIM device has other advantages over conventional one-juncti… more
Date: June 1, 1997
Creator: Fatemi, Navid S.; Jenkins, Phillip P.; Hoffman, Richard W., Jr.; Weizer, Victor G.; Wilt, David M.; Murray, Christopher S. et al.
Partner: UNT Libraries Government Documents Department
open access

Using Arc/Info GIS to help implement the National Pollutant Discharge Elimination System (NPDES) stormwater permit for Los Angeles County

Description: One of Los Angeles County Department of Public Works` many responsibilities is to manage non-point pollution that enters the storm drain network within Los Angeles County. The management of this non-point source pollution is mandated by the NPDES guidelines under the Federal Clean Water Act. These guidelines require the County to monitor the drainage network and the storm water and urban runoff flowing through it. The County covers over 3,117 square miles, with the NPDES Permit covering over 3,… more
Date: June 1, 1997
Creator: Levine, D. A.; Pace, P. J.; Woods, J. A. & DePoto, W.
Partner: UNT Libraries Government Documents Department
open access

[University of North Texas. News Service, June 19, 1997]

Description: An article titled "Chinese officials to visit UNT art seminar" about visiting delegations from the People's Republic of China to the University of North Texas June 23-24 to learn about the North Texas Institute for Educators on the Visual Arts program to improve public school learning on the arts. They are going to be touring the Sid Richardson Collection, the Kimbell Art Museum and the Amon Center Carter Museum with R. William McCarter, NTIEVA Co-director and Regent Professor of art at UNT.
Date: June 19, 1997
Creator: LeMay, Nancy
Partner: UNT Libraries Special Collections
open access

Energy-Efficiency Options for Insurance Loss Prevention

Description: Energy-efficiency improvements offer the insurance industry two areas of opportunity: reducing ordinary claims and avoiding greenhouse gas emissions that could precipitate natural disaster losses resulting from global climate change. We present three vehicles for taking advantage of this opportunity, including research and development, in- house energy management, and provision of key information to insurance customers and risk managers. The complementary role for renewable energy systems is al… more
Date: June 9, 1997
Creator: Mills, Evan & Knoepfel, Ivo
Partner: UNT Libraries Government Documents Department
open access

Nonlinear Rayleigh-Taylor Instability Experiments in Nova

Description: We examined the progression of the Rayleigh-Taylor (RT) instability from an initial multimode perturbation. The RT experiments focused on the transition from the linear to non-linear regimes for perturbation growth at an embedded, or classical, interface. The multimode experiments have attempted to observe the process of bubble competition wherein neighboring structures either continue to rise or are washed downstream in the flow depending upon; their relative size. This competition is predicte… more
Date: June 16, 1997
Creator: Budil, K. S.; Remington, B. A.; Weber, S. V.; Perry, T. S. & Peyser, T. A.
Partner: UNT Libraries Government Documents Department
open access

Concepts and applications of wireless security systems for tactical, portable, and fixed sites

Description: Intrusion detection systems sometimes use radio signals to convey sensor status in areas that wire conduits do not service or as a redundant path to wired systems. Some applications benefit from radio technology by minimizing setup time and reducing installation and operation costs. In recent years with the explosion in wireless communications, these radio-based security systems have become more capable while lowering costs, size, and power consumption. However, the very nature of radio communi… more
Date: June 1, 1997
Creator: Harrington, John J.
Partner: UNT Libraries Government Documents Department
open access

The CDF and D-zero B physics upgrades

Description: The CDF and D0 detector upgrades are reviewed with an emphasis on their B physics capabilities. Projections for the observability of CP- violation and for the resolution of rapid B{sub s} oscillations are made, based on upgrade simulations and on CDF performance from the last run. It is shown that measurements of sin(2{beta}) and sin(2{alpha}) can be achieved with uncertainties less than 0.15. For fully reconstructed (non-leptonic) B{sub s} decays, both detectors have vertexing and momentum det… more
Date: June 1, 1997
Creator: Maciel, Arthur K. A.
Partner: UNT Libraries Government Documents Department
open access

US nuclear reaction data program in support of basic research

Description: Information about the US Nuclear Reaction Data Network (USNRDN) such as its members, work in progress, summaries of meetings, and organizational details may be found in its WWW Homepage. This paper is an overview of the data support provided by the network for basic research in nuclear astrophysics, radioactive ion beams, high energy heavy-ion and electron interactions and related activities involving all aspects of data stewardship.
Date: June 1997
Creator: Bhat, M. R.; Chadwick, M. B. & Smith, M. S.
Partner: UNT Libraries Government Documents Department
open access

The gold flashlight: Coherent photons (and Pomerons) at RHIC

Description: The Relativistic Heavy Ion Collider (RHIC) will be the first heavy ion accelerator energetic enough to produce hadronic final states via coherent {gamma}{gamma}, {gamma}P, and PP interactions. Because the photon flux scales as Z{sup 2}, up to an energy of about {gamma}{h_bar}c/R {approx} 3 GeV/c, the {gamma}{gamma} interaction rates are large. RHIC {gamma}P interactions test how Pomerons couple to nuclei and measure how different vector mesons, including the J/{psi}, interact with nuclear matte… more
Date: June 1, 1997
Creator: Klein, S. & Scannapieco, E.
Partner: UNT Libraries Government Documents Department
open access

Jet Production at the Tevatron

Description: Inclusive jet cross section and dijet angular distribution results from the CDF and D0 collaborations are presented. The possibility that compositeness might be evident at high transverse energies is explored by both experiments. Using the angular distributions, the CDF analysis excludes at the 95% CL regions with {Lambda}{sup +} < 1.8 TeV and {Lambda}{sup -} < 1.6 TeV for a model where all quarks are allowed to be composite objects. The D0 preliminary result excludes at the 95% CL regions with… more
Date: June 1, 1997
Creator: Nang, F. & Collaborations, CDF and D0
Partner: UNT Libraries Government Documents Department
open access

Amp-hour counting control for PV hybrid power systems

Description: The performance of an amp-hour (Ah) counting battery charge control algorithm has been defined and tested using the Digital Solar Technologies MPR-9400 microprocessor based PV hybrid charge controller. This work included extensive field testing of the charge algorithm on flooded lead-antimony and valve regulated lead-acid (VRLA) batteries. The test results after one-year have demonstrated that PV charge utilization, battery charge control, and battery state of charge (SOC) has been significantl… more
Date: June 1, 1997
Creator: Hund, T.D. & Thompson, B.
Partner: UNT Libraries Government Documents Department
open access

A unique distribution system loss minimization scheme via reconfiguration with line capability limits

Description: This paper describes an integrated scheme for distribution system loss minimization with consideration of line capability limits via reconfiguration. Line capability limits are incorporated into the single loop optimization process as constraints. The integrated scheme is tested by 38-bus distribution system for different initial configurations, system losses are reduced significantly without any overload occurrence on feeder transformer network.
Date: June 1, 1997
Creator: Momoh, J. A.; Wang, Y. & Rizy, D. T.
Partner: UNT Libraries Government Documents Department
open access

Results from a prototype permanent magnet dipole-quadrupole hybrid for the PEP-II B-factory

Description: We describe the construction of a prototype hybrid permanent magnet dipole and quadrupole. The magnet consists of two concentric rings of Sm{sub 2}Co{sub 17} magnetic material 5 cm in length. The outer ring is made of 16 uniformly magnetized blocks assembled as a Halbach dipole and the inner ring has 32 blocks oriented in a similar fashion so as to generate a quadrupole field. The resultant superimposed field is an offset quadrupole field which allows us to center the field on the high-energy b… more
Date: June 1, 1997
Creator: Sullivan, M.; Bowden, G. & Ecklund, S.
Partner: UNT Libraries Government Documents Department
open access

Simplified propagation of standard uncertainties

Description: An essential part of any measurement control program is adequate knowledge of the uncertainties of the measurement system standards. Only with an estimate of the standards` uncertainties can one determine if the standard is adequate for its intended use or can one calculate the total uncertainty of the measurement process. Purchased standards usually have estimates of uncertainty on their certificates. However, when standards are prepared and characterized by a laboratory, variance propagation … more
Date: June 9, 1997
Creator: Shull, A.H.
Partner: UNT Libraries Government Documents Department
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