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An MPI implementation of the SPAI preconditioner on the T3E

Description: The authors describe and test spai_1.1, a parallel MPIimplementation of the sparse approximate inverse (SPAI) preconditioner.They show that SPAI can be very effective for solving a set of very largeand difficult problems on a Cray T3E. The results clearly show the valueof SPAI (and approximate inverse methods in general) as the viablealternative to ILU-type methods when facing very large and difficultproblems. The authorsstrengthen this conclusion by showing that spai_1.1also has very good scal… more
Date: September 8, 1997
Creator: Barnard, Stephen T.; Bernardo, Luis M. & Simon, Horst D.
Partner: UNT Libraries Government Documents Department
open access

Rare K Decays.

Description: In the rush to explore the B system, one should not ignore the potential of rare K decays. The charged and neutral FCNC K {yields} {pi}{nu}{bar {mu}} decays are theoretically very clean, on a par with B {yields} {psi}K{sub S}, which measures {beta}, and much less problematic than B {yields} {pi}{pi} and B{sub s} {yields} K{sup +}K{sup -} or B{sub s} {yields} K*{sup +}K*{sup -} which have been proposed to measure {alpha} and {gamma} respectively. B(K{sup +} {yields} {pi}{sup +}{nu}{bar {nu}}), w… more
Date: July 8, 1997
Creator: Littenberg, L.
Partner: UNT Libraries Government Documents Department
open access

UO{sub 2} corrosion in high surface-area-to-volume batch experiments.

Description: Unsaturated drip tests have been used to investigate the alteration of unirradiated UO{sub 2} and spent UO{sub 2} fuel in an unsaturated environment such as may be expected in the proposed repository at Yucca Mountain. In these tests, simulated groundwater is periodically injected onto a sample at 90 C in a steel vessel. The solids react with the dripping groundwater and water condensed on surfaces to form a suite of U(VI) alteration phases. Solution chemistry is determined from leachate at the… more
Date: December 8, 1997
Creator: Bates, J. K.; Finch, R. J.; Hanchar, J. M. & Wolf, S. F.
Partner: UNT Libraries Government Documents Department
open access

H + CH{sub 2}CO {yields} CH{sub 3} + CO at high temperature : a high pressure chemical activation reaction with positive barrier.

Description: The Laser Photolysis-Shock Tube (LP-ST) technique coupled with H-atom atomic resonance absorption spectrometry (ARAS) has been used to study reaction, H + CH{sub 2}CO {r_arrow} CH{sub 3} + CO, over the temperature range, 863-1400 K. The results can be represented by the Arrhenius expression, k = (4.85 {+-} 0.70) x 10{sup {minus}11} exp({minus}2328 {+-} 155 K/T) cm{sup 3} molecule{sup {minus}1} s{sup {minus}1}. The present data have been combined with the earlier low temperature flash photolysis… more
Date: December 8, 1997
Creator: Hranisavljevic, J.; Kumaran, S. S. & Michael, J. V.
Partner: UNT Libraries Government Documents Department
open access

Wake properties of a stripline beam kicker

Description: The transport of a high current relativistic electron beam in a stripline beam kicker is strongly dependent on the wake properties of the structure. The effect of the beam-induced fields on the steering of the beam must be determined for a prescribed trajectory within the structure. A 3-D time domain electromagnetic code is used to determine the wake fields and the resultant Lorentz force on the beam both for an ultra-relativistic electron beam moving parallel to the beamline axis as well as a … more
Date: May 8, 1997
Creator: Poole, B. R., LLNL
Partner: UNT Libraries Government Documents Department
open access

Using stakeholder input to develop environmental regulatory approaches : a case study.

Description: Many regulated entities today charge that environmental regulations have become inefficient and could be made more cost effective. The US Environmental Protection Agency (EPA) has identified several initiatives to help ''reinvent'' environmental regulations and address those charges. At the same time, the President and others are pursuing the development and use of new environmental technologies. Reflecting these trends, Argonne National Laboratory is helping develop a prototype multimedia envi… more
Date: December 8, 1997
Creator: Elcock, D. & Gasper, J.
Partner: UNT Libraries Government Documents Department
open access

Depletion calculations for the McClellan Nuclear Radiation Center.

Description: Depletion calculations have been performed for the McClellan reactor history from January 1990 through August 1996. A database has been generated for continuing use by operations personnel which contains the isotopic inventory for all fuel elements and fuel-followed control rods maintained at McClellan. The calculations are based on the three-dimensional diffusion theory code REBUS-3 which is available through the Radiation Safety Information Computational Center (RSICC). Burnup-dependent cross… more
Date: December 8, 1997
Creator: Klann, R. T. & Newell, D. L.
Partner: UNT Libraries Government Documents Department
open access

Novel design for a high power superconducting delay line

Description: Potential designs for a high power superconducting delay line of approximately 10ms duration are described. The transmitted signal should have low dispersion and little attenuation to recapture the original signal. Such demands cannot be met using conventional metal conductors. This paper outlines a proposal for a new transmission line design using low temperature superconducting material which meets system specifications. The 25W line is designed to carry pulsed signals with an approximate ris… more
Date: May 8, 1997
Creator: Chen, Y. J. & Caporaso, G. J.
Partner: UNT Libraries Government Documents Department
open access

Gravitational microlensing searches and results

Description: Baryonic matter, in the form of Machos (MAssive Compact Halo Objects), might be a significant constituent of the dark matter that dominates the Milky Way. This article describes how surveys for Machos exploit the gravitational microlens magnification of extragalactic stars. The experimental searches for this effect monitor millions of stars, in some cases every night, looking for magnification events. The early results of these surveys indicate that Machos make up a significant fraction of the … more
Date: May 8, 1997
Creator: Alcock, C.
Partner: UNT Libraries Government Documents Department
open access

Time domain reflectometry (TDR) instrumentation used for in-situ plasma vitrification

Description: An application of TDR (Time Domain Reflectometry) was developed and demonstrated for use with the in-situ plasma vitrification (ISPV) environmental restoration project. The technique was simple, using an inexpensive sacrificial TDR probe made out of ordinary coaxial cable. This technique proved its viability for field operation in support of the vitrification process. This presentation will detail the design, construction, operation and field results of the TDR instrumentation that was develope… more
Date: September 8, 1997
Creator: Tarpley, J.
Partner: UNT Libraries Government Documents Department
open access

Managing routine bioassay requirements

Description: The Hanford Site is a very diverse Department of Energy (DOE) Nuclear Site in Eastern Washington State that includes: retired reactor facilities, spent fuel storage facilities, chemical separations facilities, laboratories, and plutonium separations facilities. As a result worker routine bioassays requirements may include routine whole body counting for mixed fission products, chest counting for uranium or plutonium, and/or urinalyses for plutonium, ura@u@ strontium-90, and tritium depending on… more
Date: October 8, 1997
Creator: Baumann, B. L.
Partner: UNT Libraries Government Documents Department
open access

Application of Phosphor Thermometry to Galvanneal Processing

Description: A system has been developed for determining temperatures of galvanneal steel during the production process. It is based on an optical method known as phosphor thermometry and it provides for reliable, emissivity-independent measurements. This development is a part of the American Iron and Steel Institute`s (AISI) Advanced Process Control Program, a joint endeavor between the AISI and the U.S. Department of Energy. Galvanneal is a corrosion-resistant steel that is widely used for automotive and … more
Date: May 8, 1997
Creator: Beshears, D. L.; Abston, R. A. & Allison, S. W.
Partner: UNT Libraries Government Documents Department
open access

WWW-based data entry for document clearance requests

Description: All documents created at Argonne must be cleared before being published. The clearance process is coordinated by the Publications and Record Services. The Electronic Document Review and Clearance System (EDRC) consists of a Web-based system for submission of clearance requests, an electronic staging area for document awaiting review, and Web-based review and clearance of documents. This report covers the document clearing process, the EDRC system, expected benefits/costs, and a demonstration.
Date: October 8, 1997
Creator: Stasiak, D. M.
Partner: UNT Libraries Government Documents Department
open access

Study of performance on SMP and distributed memory architectures using a shared memory programming model

Description: In this paper we examine the use of a shared memory programming model to address the problem of portability of application codes between distributed memory and shared memory architectures. We do this with an extension of the Parallel C Preprocessor. The extension, borrowed from Split-C and AC, uses type qualifiers instead of storage class modifiers to declare variables that are shared among processors. The type qualifier declaration supports an abstract shared memory facility on distributed mem… more
Date: August 8, 1997
Creator: Brooks, E.D. & Warren, K.H.
Partner: UNT Libraries Government Documents Department
open access

Formal language constrained path problems

Description: In many path finding problems arising in practice, certain patterns of edge/vertex labels in the labeled graph being traversed are allowed/preferred, while others are disallowed. Motivated by such applications as intermodal transportation planning, the authors investigate the complexity of finding feasible paths in a labeled network, where the mode choice for each traveler is specified by a formal language. The main contributions of this paper include the following: (1) the authors show that th… more
Date: July 8, 1997
Creator: Barrett, C.; Jacob, R. & Marathe, M.
Partner: UNT Libraries Government Documents Department
open access

Nova experiments to investigate hydrodynamic instabilities in the solid state

Description: Experiments were done to shock compress and accelerate copper foils at peak presssures of {approximately}3 Mbar above and below the melt temperature to study the effects of material strength on hydrodynamic instabilities. An x-ray drive generated in a hohlraum target was used to generate the shock wave profiles. The growth of a preimposed perturbation at an embedded interface is diagnosed by x-ray radiography. Results obtained using a high contrastshaped laser pulse show that the growth of the … more
Date: July 8, 1997
Creator: Kalantar, D. H.; Remington, B. A.; Chandler, E. A.; Colvin, J. D.; Griswold, D. L.; Turner, R. E. et al.
Partner: UNT Libraries Government Documents Department
open access

A system safety approach to the FAA surveillance process

Description: As commercial air travel grows in terms of the number of passenger miles flown, there is expected to be a corresponding dramatic increase in the absolute number of accidents. This despite an enviable safety record and a very low accident rate. The political environment is such that an increase in the absolute number of accidents is not acceptable, with a stated goal of a factor of five reduction in the aviation fatal accident rate within ten years. The objective of this project is to develop an… more
Date: August 8, 1997
Creator: Werner, P. W. & Olson, D. R.
Partner: UNT Libraries Government Documents Department
open access

{pi} kinks in the parametrically driven sine-Gordon equation and applications

Description: Parametrically driven sine-Gordon equation with a mean-zero forcing is considered. It is shown that the system is well approximated by the double sine-Gordon equation using the normal form technique. The reduced equation possesses {pi}-kink solutions, which are also observed numerically in the original system. This result is applied to domain walls dynamics in one-dimensional easy-plane ferromagnets. For such system the existence of {pi}-kinks implies the true domain structure in the presence o… more
Date: July 8, 1997
Creator: Zharnitsky, V. & Mitkov, I.
Partner: UNT Libraries Government Documents Department
open access

National Ignition Facility for Inertial Confinement Fusion

Description: The National Ignition Facility for inertial confinement fusion will contain a 1.8 MJ, 500 TW frequency-tripled neodymium glass laser system that will be used to explore fusion ignition and other problems in the physics of high temperature and density. We describe the facility briefly. The NIF is scheduled to be completed in 2003.
Date: October 8, 1997
Creator: Paisner, J.A. & Murray, J.R.
Partner: UNT Libraries Government Documents Department
open access

Mixed Waste Focus Area Working Group: An Integrated Approach to Mercury Waste Treatment and Disposal. Revision 1

Description: May 1996, the U.S. Department of Energy (DOE) Mixed Waste Focus Area (MWFA) initiated the Mercury Work Group (HgWG). The HgWG was established to address and resolve the issues associated with Mercury- contaminated mixed wastes (MWs). During the initial technical baseline development process of the MWFA, three of the top four technology deficiencies identified were related to (1) amalgamation, (2) stabilization, and (3) separation and removal for the treatment of mercury and mercury-contaminated… more
Date: September 8, 1997
Creator: Morris, M. I.; Conley, T. B. & Osborne-Lee, I. W.
Partner: UNT Libraries Government Documents Department
open access

Statistics of flame displacement speeds from computations of 2-D unsteady methane-air flames

Description: Results of two-dimensional numerical computations of turbulent methane flames using detailed and reduced chemistry are analyzed in the context of a new theory for premixed turbulent combustion for high turbulence intensity. This theory defines the thin reaction zones regime, where the Kolmogorov scale is smaller than the preheat zone thickness, but larger than the reaction zone thickness. The two numerical computations considered in this paper fall clearly within this regime. A lean and a stoic… more
Date: December 8, 1997
Creator: Peters, N.; Terhoeven, P.; Chen, J.H. & Echekki, T.
Partner: UNT Libraries Government Documents Department
open access

Incorporation of pollution prevention into the engineering command media

Description: It has long been recognized that incorporation of pollution prevention (P2) into projects during the design phase yields superior results as compared to modification of facilities after construction. Generation of waste during construction can be minimized, products containing recycled materials can be incorporated into the facility, and the processes or systems can be optimized for P2 from the beginning. However, design engineers must have the proper mindset and training in order to achieve th… more
Date: October 8, 1997
Creator: Harrington, E. & Hammonds, C.
Partner: UNT Libraries Government Documents Department
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