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A second order accurate embedded boundary method for the wave equation with Dirichlet data

Description: The accuracy of Cartesian embedded boundary methods for the second order wave equation in general two-dimensional domains subject to Dirichlet boundary conditions is analyzed. Based on the analysis, we develop a numerical method where both the solution and its gradient are second order accurate. We avoid the small-cell stiffness problem without sacrificing the second order accuracy by adding a small artificial term to the Dirichlet boundary condition. Long-time stability of the method is obtain… more
Date: March 2, 2004
Creator: Kreiss, H O & Petersson, N A
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Indonesia-U.S. Economic Relations

Description: This report examines the factors that bolster or weaken international relations between the U.S. and Indonesian including the rise of separatist movements and terrorist activities in Indonesia.
Date: March 2, 2004
Creator: Morrison, Wayne M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Gravitational Baryogenesis

Description: We show that a gravitational interaction between the derivative of the Ricci scalar curvature and the baryon-number current dynamically breaks CPT in an expanding universe and, combined with baryon-number-violating interactions, can drive the universe towards an equilibrium baryon asymmetry that is observationally acceptable.
Date: March 2, 2004
Creator: Davoudias, Hooman; Kitano, Ryuichiro; Kribs, Graham D.; Murayama, Hitoshi & Steinhardt, Paul J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Massive Star Formation in a Gravitationally-Lensed H II Galaxy at z = 3.357

Description: The Lynx arc, with a redshift of 3.357, was discovered during spectroscopic follow-up of the z = 0.570 cluster RX J0848+4456 from the ROSAT Deep Cluster Survey. The arc is characterized by a very red R - K color and strong, narrow emission lines. Analysis of HST WFPC 2 imaging and Keck optical and infrared spectroscopy shows that the arc is an H II galaxy magnified by a factor of {approx} 10 by a complex cluster environment. The high intrinsic luminosity, the emission line spectrum, the absorpt… more
Date: March 2, 2004
Creator: Villar-Martin, M.; Stern, D.; Hook, R. N.; Rosati, P.; Lombardi, M.; Humphrey, A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

The K-selected Butcher-Oemler Effect

Description: We investigate the Butcher-Oemler effect using samples of galaxies brighter than observed frame K* + 1.5 in 33 clusters at 0.1 {approx}< z {approx}< 0.9. We attempt to duplicate as closely as possible the methodology of Butcher & Oemler. Apart from selecting in the K-band, the most important difference is that we use a brightness limit fixed at 1.5 magnitudes below an observed frame K* rather than the nominal limit of rest frame M(V ) = -20 used by Butcher & Oemler. For an early type gala… more
Date: March 2, 2004
Creator: Stanford, S. A.; De Propris, R.; Dickinson, M. & Eisenhardt, P. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

[Press release: The Black Academy of Arts and Letters Presents A FilmFeast and Film Talk with Actor and Producer Tim Reid on Saturday, March 13, 2004]

Description: Press release from the Black Academy of Arts and Letters discussing a film festival featuring actor Tim Reid on March 13, 2004 at the Dallas Convention Center Theatre Complex.
Date: March 2, 2004
Creator: Black Academy of Arts and Letters
Item Type: Refine your search to only Text
Partner: UNT Libraries Special Collections
open access

Even parity theta-pentaquark and stable strange nuclear matter

Description: The newly discovered exotic {Theta} baryon of mass 1540 MeV (and very small width) truly has a very low mass, if it is a pentaquark system of even parity. A schematic model in which the coherent interaction of u{bar s} and d{bar s} pairs leads to a very large residual (non-confining) attractive interaction is introduced. This collective vibrational model accounts for the mass and small decay width to the KN channel, but yields a significant coupling to the virtual K*N channel. The schematic mod… more
Date: March 2, 2004
Creator: Miller, Gerald A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Pump Side-scattering in Ultra-powerful Backward Raman Amplifiers

Description: Extremely large laser power might be obtained by compressing laser pulses through backward Raman amplification (BRA) in plasmas. Premature Raman backscattering of a laser pump by plasma noise might be suppressed by an appropriate detuning of the Raman resonance, even as the desired amplification of the seed persists with a high efficiency. In this paper, we analyze side-scattering of laser pumps by plasma noise in backward Raman amplifiers. Though its growth rate is smaller than that of backsca… more
Date: March 2, 2004
Creator: A.A. Solodov, V.M. Malkin, and N.J. Fisch
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

SURFACE FACILITY CRITICALITY SAFETY CALCULATIONS

Description: The purpose of this design calculation is to revise and update the previous criticality evaluation for the fuel handling, transfer and storage operations to be performed in the Surface Facility documented in BSC 2003c. The scope of this design calculation covers the operations in the Dry Transfer Facility (DTF) and Remediation Building (RB) and their processes as established at the date of this calculation. Also, this design calculation focuses on intact commercial spent nuclear fuel (SNF) asse… more
Date: March 2, 2004
Creator: Sanders, C.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Indoor Measurements of Environmental Tobacco Smoke Final Report to the Tobacco Related Disease Research Program

Description: The objective of this research project was to improve the basis for estimating environmental tobacco smoke (ETS) exposures in a variety of indoor environments. The research utilized experiments conducted in both laboratory and ''real-world'' buildings to (1) study the transport of ETS species from room to room, (2) examine the viability of using various chemical markers as tracers for ETS, and (3) to evaluate to what extent re-emission of ETS components from indoor surfaces might add to the ETS… more
Date: March 2, 2004
Creator: Apte, Michael G.; Gundel, Lara A.; Dod, Raymond L.; Russell, Marion L.; Singer, Brett C.; Sohn, Michael D. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Practical superconductor development for electrical power applications - quarterly report for the period ending Dec. 31, 2003.

Description: This is a multiyear experimental research program that focuses on improving relevant material properties of high-critical temperature (Tc) superconductors and developing fabrication methods that can be transferred to industry for production of commercial conductors. The development of teaming relationships through agreements with industrial partners is a key element of the Argonne National Laboratory (ANL) program.
Date: March 2, 2004
Creator: Dorris, S. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Tracking Current Federal Legislation and Regulations: A Guide to Basic Sources

Description: This report introduces selected basic sources that are useful in obtaining background information or specific facts on the status of federal legislative or regulatory initiatives. It includes telephone, online, and media sources are included, as well as pertinent directories, such as those of organizations that track areas of interest. Annotations describing each source's contents and organization are included so that researchers can select those that most closely fit their needs. Internet addr… more
Date: March 2, 2004
Creator: Davis, Carol D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Chemical Kinetic Modeling of HMX and TATB Laser Ignition Tests

Description: Recent laser ignition experiments on octahydro-1,3,5,7-tetranitro-1,3,5,7-terrazocine (HMX) and 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) subjected to laser fluxes ranging from 10 to 800 W/cm{sup 2} produced ignition times from seconds to milliseconds. Global chemical kinetic thermal decomposition models for HMX and TATB have been developed to calculate times to thermal explosion for experiments in the seconds to days time frame. These models are applied to the laser ignition experimental dat… more
Date: March 2, 2004
Creator: Tarver, C M
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

A Manufacturing Process for Precision Gold Support Rings for Laser Targets

Description: A research effort performed by the Target Fabrication Group has developed a method for producing precision, meso-scale gold support rings for laser targets. Many different laser targets consist of planar components that are built upon a gold support ring, such as the HyDiv and RadG targets shown in Figure 1. Because of the sequence in which laser targets such as these must be built to achieve the required overall precision, the washer-shaped support rings must fit precisely onto fixtures that a… more
Date: March 2, 2004
Creator: Hibbard, R L & Bono, M J
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Material Strength at High Pressure LDRD Strategic Initiative Final Report

Description: Various aspects of the Laboratory's national security mission are now highly dependent on accurate computer code simulations of plastic flow (i.e., non-reversible deformation) of materials under conditions of high hydrostatic pressure. Strength models are typically dependent on pressure, temperature, and strain rate. Current strength models can not be extrapolated to high pressure because they are not based on the underlying mechanisms of plastic deformation. The critical need for predictive mo… more
Date: March 2, 2004
Creator: Lassila, D. H.; Bonner, B. P.; Bulatov, V. V.; Cazamias, J. U.; Chandler, E. A.; Farber, D. L. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Mesochem: Chemical Dynamics on a Mesoscopic Scale

Description: Most chemically stable organic materials age through changes on the mesoscopic scale (from 10 nm to 10 mm). Examples include the slow crystallization of polymers, changes in particle size distributions with age, and the swelling of pressed powders. We began the Mesochem project to develop a new mesoscopic modeling capability for organic materials, including polymers, molecular crystals, and filled polymer composites. Our goal was to develop and validate novel mesoscopic modeling techniques that… more
Date: March 2, 2004
Creator: Fried, L E; Calef, D F; Wu, C J & Gee, R H
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Characterization of Environmental Stability of Pulsed Laser Deposited Oxide Ceramic Coatings

Description: A systematic investigation of candidate hydrogen permeation materials applied to a substrate using Pulsed Laser Deposition has been performed. The investigation focused on application of leading permeation-resistant materials types (oxide, carbides, and metals) on a stainless steel substrate. and evaluation of the stability of the applied coatings. Type 304L stainless steel substrates were coated with aluminum oxide, chromium oxide, and aluminum. Characterization of the coating-substrate system… more
Date: March 2, 2004
Creator: Adams, Thad M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

COMPARATIVE EVALUATION OF AMBIENT FINE PARTICULATE MATTER (PM2.5) DATA OBTAINED FROM URBAN AND RURAL MONITORING SITES ALONG THE UPPER OHIO RIVER VALLEY

Description: Advanced Technology Systems, Inc. (ATS), with Desert Research Institute (DRI) and Ohio University as subcontractors, was contracted by the NETL in September 1998 to manage the Upper Ohio River Valley Project (UORVP), with a goal of characterizing the ambient fine particulate in this region, including examination of urban/rural variations, correlations between PM{sub 2.5} and gaseous pollutants, and influences of artifacts on PM{sub 2.5} measurements in this region. Two urban and two rural monit… more
Date: March 2, 2004
Creator: Khosah, Robinson P. & Shimshock, John P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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