Stability Analysis of Large-Scale Incompressible Flow Calculations on Massively Parallel Computers (open access)

Stability Analysis of Large-Scale Incompressible Flow Calculations on Massively Parallel Computers

A set of linear and nonlinear stability analysis tools have been developed to analyze steady state incompressible flows in 3D geometries. The algorithms have been implemented to be scalable to hundreds of parallel processors. The linear stability of steady state flows are determined by calculating the rightmost eigenvalues of the associated generalize eigenvalue problem. Nonlinear stability is studied by bifurcation analysis techniques. The boundaries between desirable and undesirable operating conditions are determined for buoyant flow in the rotating disk CVD reactor.
Date: October 25, 1999
Creator: Lehoucq, Richard B.; Romero, Louis & Salinger, Andrew G.
Object Type: Article
System: The UNT Digital Library
Hard Exclusive and Processes in QCD (open access)

Hard Exclusive and Processes in QCD

Exclusive and semi-exclusive processes, the diffractive dissociation of hadrons into jets, and hard diffractive processes such as vector meson leptoproduction provide new testing grounds for QCD and essential information on the structure of light-cone wavefunctions of hadrons, particularly the pion distribution amplitude. I review the basic features of the leading-twist QCD predictions and the problems and challenges of studying QCD at the amplitude level. The application of the light-cone formalism to the exclusive semi-leptonic decay of heavy hadrons is also discussed.
Date: August 25, 1999
Creator: Brodsky, Stanley J.
Object Type: Report
System: The UNT Digital Library
Resonant excitation of plasma wakefields using multiple electron bunches. (open access)

Resonant excitation of plasma wakefields using multiple electron bunches.

We plan to resonantly excite plasma wakefields using a train of electron bunches separated by an-integer number of plasma wavelengths. The multiple electron bunches are generated by a photocathode based RF gun by splitting the laser beam into temporally separated pulses. The amplitude of the wakefields generated by the sequence of bunches is expected to be higher than that generated if all charge had been in only one bunch, because this single bunch would be considerably longer than the individual sub-bunches due to space charge effects in our gun.
Date: September 25, 1998
Creator: Conde, M. E.
Object Type: Article
System: The UNT Digital Library
Theoretical status of {epsilon}{prime}/{epsilon} (open access)

Theoretical status of {epsilon}{prime}/{epsilon}

The author gives a detailed introduction into the theoretical formalism for {epsilon}{prime}/{epsilon}, which measures direct CP-violation in K {yields} {pi}{pi} decays. The current status of hadronic matrix elements and the strange quark mass is discussed. Several possible explanations of the unexpectedly high experimental results for {epsilon}{prime}/{epsilon} are pointed out: A small strange quark mass, an enhancement of the hadronic parameter B{sub 6}{sup (1/2)} from the {sigma} resonance, an underestimate of isospin breaking and possible new physics contributions in the {bar s}dZ-vertex and the {bar s}d-gluon-vertex.
Date: October 25, 1999
Creator: Nierste, Ulrich
Object Type: Article
System: The UNT Digital Library
International petroleum statistics report, August 1995 (open access)

International petroleum statistics report, August 1995

The International Petroleum Statistics Report presents data on international oil production, demand, imports, exports, and stocks. The report has four sections. Section 1 contains time series data on world oil production, and on oil demand and stocks in the Organization for Economic Cooperation and Development (OECD). This section contains annual data beginning in 1985, and monthly data for the most recent two years. Section 2 presents an oil supply/demand balance for the world. This balance is presented in quarterly intervals for the most recent two years. Section 3 presents data on oil imports by OECD countries. This section contains annual data for the most recent year, quarterly data for the most recent two quarters, and monthly data for the most recent twelve months. Section 4 presents annual time series data on world oil production and oil stocks, demand, and trade in OECD countries. World oil production and OECD demand data are for the years 1970 through 1994; OECD stocks from 1973 through 1994; and OECD trade from 1984 through 1994.
Date: August 25, 1995
Creator: unknown
Object Type: Report
System: The UNT Digital Library
340 Facility emergency preparedness hazards assessment (open access)

340 Facility emergency preparedness hazards assessment

This document establishes the technical basis in support of Emergency Planning activities for the 340 Facility on the Hanford Site. Through this document, the technical basis for the development of facility specific Emergency Action Levels and Emergency Planning Zone, is demonstrated.
Date: November 25, 1998
Creator: CAMPBELL, L.R.
Object Type: Report
System: The UNT Digital Library
Effects of Pb and Bi cross sections on ATW subcriticality predictions. (open access)

Effects of Pb and Bi cross sections on ATW subcriticality predictions.

The accelerator-driven transmutation of waste (ATW) system has been proposed for transmuting the long-lived radioactive nuclei of high-level waste to stable or short-lived species. In recent ATW design concepts, lead-bismuth eutectic (LBE), consisting of 44.5% Pb and 55.5% Bi by weight is used as the spallation target, system coolant, and reflector. Because of the excellent neutron reflection properties of LBE, the subcriticality level of ATW is quite sensitive to the cross sections of lead and bismuth. The purpose of this paper is to investigate the effects of these cross sections on subcriticality and other core characteristics of ATW and to compare the results obtained using cross sections in different evaluated nuclear data files. The effects of lead and bismuth cross sections on the core characteristics of ATW were studied using 33 group cross section sets derived from the ENDF/B-VI, ENDF/B-V, JENDL-3.2, and BROND-2.2 nuclear data. A 2000 MW(thermal) ATW configuration similar to that described in Reference 1 was used in this study. In this configuration, the spallation target region is 55 cm high and 25 cm in radius, and is surrounded by a 15-cm thick LBE buffer. The adjacent fueled region is {approximately}65 cm thick and 200 cm high. The …
Date: June 25, 1999
Creator: Khalil, H. S. & Yang, W. S.
Object Type: Article
System: The UNT Digital Library
A standard interface for debugger access to message queue information in MPI. (open access)

A standard interface for debugger access to message queue information in MPI.

This paper discusses the design and implementation of an interface that allows a debugger to obtain the information necessary to display the contents of the MPI message queues. The design has been implemented in the TotalView debugger, and dynamic libraries that conform to the interface exist for MPICH, as well as the proprietary MPI implementations from Compaq, IBM, and SGI.
Date: June 25, 1999
Creator: Cownie, James & Gropp, William
Object Type: Article
System: The UNT Digital Library
The effect of chemical composition on the PCT durability of mixed waste glasses from wastewater treatment sludges (open access)

The effect of chemical composition on the PCT durability of mixed waste glasses from wastewater treatment sludges

An experimental program has been designed to examine the chemical durability of glass compositions derived from the vitrification of simulated wastewater treatment sludges. These sludges represent the majority of low-level mixed wastes currently in need of treatment by the US DOE. The major oxides in these model glasses included SiO{sub 2}, Al{sub 2}O{sub 3}, B{sub 2}O{sub 3}, Na{sub 2}O, CaO and Fe{sub 2}O{sub 3}. In addition, three minor oxides, BaO, NiO, and PbO, were added as hazardous metals. The major oxides were each varied at two levels resulting in 32 experimental glasses. The chemical durability was measured by the 7-Day Product Consistency Test (PCT). The normalized sodium release rates (NRR{sub Na}) of these glasses ranged from 0.01 to 4.99 g/m{sup 2}. The molar ratio of the glass-former to glass-modifier (F/M) was found to have the greatest effect on PCT durability. Glass-formers included SiO{sub 2}, Al{sub 2}O{sub 3}, and B{sub 2}O{sub 3}, while Na{sub 2}O, CaO, BaO, NiO, and PbO were glass-modifiers. As this ratio increased from 0.75 to 2.0, NRR{sub Na} was found to decrease between one and two orders of magnitude. Another important effect on NRR{sub Na} was the Na{sub 2}O/CaO ratio. As this ratio increased from 0.5 to …
Date: January 25, 1995
Creator: Resce, James L.; Ragsdale, R. Giles; Overcamp, Thomas J.; Bickford, Dennis F. & Cicero, Connie A.
Object Type: Article
System: The UNT Digital Library
Closure Report for CAU No. 430: Buried Depleted Uraniuim Artillery Round No. 1, Tonopah Test Range, Revision 0 (open access)

Closure Report for CAU No. 430: Buried Depleted Uraniuim Artillery Round No. 1, Tonopah Test Range, Revision 0

1.1 Purpose This Closure Report presents the information obtained from investigative actions performed to justify the decision for clean closure of CAU 430 through "No Further Action." The investigative actions were performed per the Streamlined Approach for Environmental Restoration Plan, CA UNO. 430: Buried Depleted Uranium Artille~ Round No. 1, Tonopah Test Range (DOE/NV, 1996a) (hereafter referred to as the SAFER Plan). The Buried DU Artillery Round No. 1 is located approximately 1.1 kilometers (km) (0.7 mile [mi]) south of Avenue 13 in the test area south of Area 9 (Figure 1-2). The site was thought to consist of a potentially unexploded W-79 Joint Test Assembly (JTA) test artillery projectile with high explosives (HE) and DU. The DU was substituted for Special Nuclear Material to prevent a nuclear explosion and yet retain the physical characteristics of uranium for ballistic and other mechanical tests. The projectile was reportedly buried in one pit, approximately 5 to 10 feet (ft) deep (Smith, 1993; Smith, 1996; Quas, 1996). The exact location of the burial pit is unknown; however, three disturbed areas (Sites A, B, and C) were identified through geophysical surveys, site visits, and employee interviews as possible locations of the test projectile (Figure …
Date: February 25, 1997
Creator: unknown
Object Type: Report
System: The UNT Digital Library
CENRTC Project {number_sign}2F3EOA, OCB A-376, acceptance test procedure (open access)

CENRTC Project {number_sign}2F3EOA, OCB A-376, acceptance test procedure

This test procedure provides the steps necessary to verify correct functional operation of controls, annunciators, alarms, protective relays and related systems impacted by CENRTC {number_sign}2F3E0A, Microwave Transfer Trip Project, modification work performed under work package 6B-93-00041/M. This procedure separates three tests into separate sections: energization of A-376 duplex panel and circuits; SCADA tests; and A-376 local trip tests.
Date: January 25, 1995
Creator: Akerson, A. W.
Object Type: Report
System: The UNT Digital Library
Tank 241-TX-105 headspace gas and vapor characterization results for samples collected in December 1995 (open access)

Tank 241-TX-105 headspace gas and vapor characterization results for samples collected in December 1995

Significant changes have been made to all of the original vapor characterization reports. This report documents specific headspace gas and vapor characterization results for all vapor sampling events to date. In addition, changes have been made to the original vapor reports to qualify the data based on quality assurance issues associated with the performing laboratories
Date: September 25, 1995
Creator: Huckaby, J.L. & Bratzel, D.R.
Object Type: Report
System: The UNT Digital Library
Diamond switches for high temperature electronics (open access)

Diamond switches for high temperature electronics

Diamond switches are well suited for use in high temperature electronics. Laboratory feasibility of diamond switching at 1 kV and 18 A was demonstrated. DC blocking voltages up to 1 kV were demonstrated. A 50 {Omega} load line was switched using a diamond switch, with switch on-state resistivity {approx}7 {Omega}-cm. An electron beam, {approx}150 keV energy, {approx}2 {mu}s full width at half maximum was used to control the 5 mm x 5 mm x 100 {mu}m thick diamond switch. The conduction current temporal history mimics that of the electron beam. These data were taken at room temperature.
Date: April 25, 1996
Creator: Prasad, R. R.; Rondeau, G. & Qi, Niansheng
Object Type: Article
System: The UNT Digital Library
Natural Gas Monthly, March 1996 (open access)

Natural Gas Monthly, March 1996

The Natural Gas Monthly (NGM) highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time, the NGM features articles designed to assist readers in using and interpreting natural gas information.
Date: March 25, 1996
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Managing in an environmentally constrained world (open access)

Managing in an environmentally constrained world

In thinking about this issue, one comes to fundamental question: Why are we concerned at all? Why have all of us gathered here, rather than simply continue to clean up what we should from the past and control our emissions for the present and the future? The answer, I think, may be hinted at by several scenarios (which, although plausible given current trends, are intended to be hypothetical).
Date: September 25, 1995
Creator: Allenby, B.R.
Object Type: Article
System: The UNT Digital Library
Thermogravimetric analysis studies (open access)

Thermogravimetric analysis studies

Independent of thermal loading scenarios, the waste packages at the proposed repository at Yucca Mountain, Nevada will be exposed to environmental conditions of temperatures below 100 C with a range of possible relative humidities. Under high relative humidities, the formation of thin water films on the metal surfaces will occur. Previous work at ambient conditions has shown that on susceptible metals, the water-film-covered metal has an enhanced corrosion rate relative to the dry oxidation of the metal. The transition relative humidity where oxidation changes from dry oxidation to aqueous electrochemical corrosion is called the critical relative humidity. Determination of this transition is important in estimating the performance of the candidate materials (especially corrosion allowance materials), because of the marked increase in degradation rate above the critical relative humidity, typically 10-10{sup 2} times This activity is concerned with short term measurements of corrosion and oxidation rates using a high sensitivity microbalance. The experimental work will determine the critical humidity level for candidate metals under a variety of conditions. From the literature, the critical humidity level typically are around 70% relative humidity, but this level is affected by the metal, gas composition, temperature, and the presence of contaminants on the surface, particularly …
Date: August 25, 1995
Creator: Gdowski, G.
Object Type: Report
System: The UNT Digital Library
Slag characterization and removal using pulse detonation for coal gasification. Quarterly research report, October--December, 1995 (open access)

Slag characterization and removal using pulse detonation for coal gasification. Quarterly research report, October--December, 1995

Experiments will mainly focus on breaking the bonds within the slag itself using detonation wave. For the experiments, initial suggestion was to build up slag deposit around a representative tube by placing it inside the convection pass of an actual boiler at the Northern States Power Company. But it was later concluded that once the tube is cooled to room condition, the thermal stress will greatly reduce the bonding between the heat transfer surface and the slag. It was concluded that the slag will be attached to the tube using high density epoxy resin. High density epoxy will be used so that they do not diffuse into the slag and strengthen the bonding within the slag. Suggestions on candidate epoxy are provided by MTI lab. MTI also provided PVAMU with different kinds of slags for testing. The deposits for characterization were from a subbituminous coal fired utility boiler.
Date: December 25, 1995
Creator: Huque, Z.; Zhou, J.; Mei, D. & Biney, P.O.
Object Type: Report
System: The UNT Digital Library
Development of a data management system for assistance in conducting Area of Reviews (AORs) on Class II injection wells in Oklahoma. Quarterly report, July--September, 1995 (open access)

Development of a data management system for assistance in conducting Area of Reviews (AORs) on Class II injection wells in Oklahoma. Quarterly report, July--September, 1995

Project objectives are to provide the resources and capabilities to permit the State of Oklahoma to conduct Area of Review (AOR) variance analysis on a statewide level including: (1) the analysis and identification of areas which may qualify for AOR variances; (2) the correlation of information from various databases and automation systems to conduct AORs in areas that do not qualify for variances; (3) the evaluation of the risk of pollution, during permitting and monitoring, using risk based data analysis; and (4) the ability to conduct spatial analysis of injection well data in conjunction with other geographically referenced information. The division successfully converted its mainframe computer surety system to the new client server network and implemented it on September 29, 1995. The division currently lacks sufficient storage space to bring the existing oil and gas spatially referenced data systems in-house and fully integrate the systems for use in the determination of AORs or AOR variances. The second installment of the awarded grant allows for the purchase of the developmental server that will provide the minimum computer storage space to convert the remainder of the mainframe computer systems.
Date: October 25, 1995
Creator: Schmidt, M.W.
Object Type: Report
System: The UNT Digital Library
Maintenance of the coal sample bank and database. Quarterly technical progress report, January 1, 1995--March 31, 1995 (open access)

Maintenance of the coal sample bank and database. Quarterly technical progress report, January 1, 1995--March 31, 1995

This project is concerned with the development of a coal database providing information to the public and private research sectors on 30 coal samples. The information from these samples, along with information previously collected on 26 samples, will be distributed to DOE contractors performing coal research.
Date: August 25, 1995
Creator: Davis, A. & Glick, D. C.
Object Type: Report
System: The UNT Digital Library
Vapor and gas sampling of single-shell tank 241-BY-108 using the vapor sampling system (open access)

Vapor and gas sampling of single-shell tank 241-BY-108 using the vapor sampling system

This document presents sampling data resulting from the October 27, 1994, sampling of SST 241-BY-108 using the vapor sampling system.
Date: September 25, 1995
Creator: Caprio, G.S.
Object Type: Report
System: The UNT Digital Library
Adaptive Remote-Sensing Techniques Implementing Swarms of Mobile Agents (open access)

Adaptive Remote-Sensing Techniques Implementing Swarms of Mobile Agents

In many situations, stand-off remote-sensing and hazard-interdiction techniques over realistic operational areas are often impractical "and difficult to characterize. An alternative approach is to implement an adap- tively deployable array of sensitive agent-specific devices. Our group has been studying the collective be- havior of an autonomous, multi-agent system applied to chedbio detection and related emerging threat applications, The current physics-based models we are using coordinate a sensor array for mukivanate sig- nal optimization and coverage as re,alized by a swarm of robots or mobile vehicles. These intelligent control systems integrate'glob"ally operating decision-making systems and locally cooperative learning neural net- works to enhance re+-timp operational responses to dynarnical environments examples of which include obstacle avoidance, res~onding to prevailing wind patterns, and overcoming other natural obscurants or in- terferences. Collectively',tkensor nefirons with simple properties, interacting according to basic community rules, can accomplish complex interconnecting functions such as generalization, error correction, pattern recognition, sensor fusion, and localization. Neural nets provide a greater degree of robusmess and fault tolerance than conventional systems in that minor variations or imperfections do not impair performance. The robotic platforms would be equipped with sensor devices that perform opticaI detection of biologicais in combination with multivariate chemical analysis tools …
Date: November 25, 1998
Creator: Asher, R. B.; Cameron, S. M.; Loubriel, G. M.; Robinett, R. D.; Stantz, K. M.; Trahan, M. W. et al.
Object Type: Article
System: The UNT Digital Library
Corrosion Testing of Low-Activity Waste Glasses Fiscal Year 1998 Summary Report (open access)

Corrosion Testing of Low-Activity Waste Glasses Fiscal Year 1998 Summary Report

Analytical results are presented on the chemical composition and other physical properties of a glass, given the identification BNFL-A-S98, made at Pacific Northwest National Laboratory' that is representative of the low-activity waste glass composition proposed by BNFL, Inc.* for immobilization of envelope A double-shell tank wastes at the Hanford Site. This glass was prepared for use in a testing program to be conducted at Pacific Northwest National Laboratory and at Argonne National Laboratory for the purpose of characterizing its long-term corrosion behavior. Detailed examination of the glass microstructure using transmission electron microscopy showed structural features indicative of amorphous phase separation. A remelt was performed on a smaller batch (100 g) to ensure rapid cooling. The glass microstructure was reexamined and showed no evidence of phase separation. Selected long-term (some to 860 d) product consistency tests were terminated, and the leachates were analyzed on tests with three other representative low-activity waste glass formulations (L8- 1, L8-3, and L8-7). The results showed no evidence of corrosion rate acceleration at three times the duration of tests where another well-studied glass, LD6-5412, had been completely altered under identical test conditions. These tests (and others not discussed in this report) provide clear evidence that low-activity …
Date: November 25, 1998
Creator: McGrail, BP; Lindenmeier, CW; Schaef, HT & Martin, PF
Object Type: Report
System: The UNT Digital Library
Experimental Physics and Industrial Control System (EPICS): Application source/release control for EPICS R3.11.6 (open access)

Experimental Physics and Industrial Control System (EPICS): Application source/release control for EPICS R3.11.6

This manual describes a set of tools that can be used to develop software for EPICS based control systems. It provides the following features: Multiple applications; the entire system is composed of an arbitrary number of applications: Source/Release Control; all files created or modified by the applications developers can be put under sccs (a UNIX Source/Release control utility): Multiple Developers; it allows a number of applications developers to work separately during the development phase but combine their applications for system testing and for a production system; Makefiles: makefiles are provided to automatically rebuild various application components. For C and state notation programs, Imagefiles are provided.
Date: March 25, 1994
Creator: Zieman, B. & Kraimer, M.
Object Type: Report
System: The UNT Digital Library
Microbial activity at Yucca Mountain (open access)

Microbial activity at Yucca Mountain

The U.S. Department of Energy is engaged in a suitability study for a potential geological repository at Yucca Mountain, Nevada, for the containment and storage of commercially generated spent fuel and defense high-level nuclear waste. There is growing recognition of the role that biotic factors could play in this repository, either directly through microbially induced corrosion (MIC), or indirectly by altering the chemical environment or contributing to the transport of radionuclides. As a first step toward describing and predicting these processes, a workshop was held on April 10-12, 1995, in Lafayette, California. The immediate aims of the workshop were: (1) To identify microbially related processes relevant to the design of a radioactive waste repository under conditions similar to those at Yucca Mountain. (2) To determine parameters that are critical to the evaluation of a disturbed subterranean environment. (3) To define the most effective means of investigating the factors thus identified.
Date: September 25, 1995
Creator: Horn, J.M. & Meike, A.
Object Type: Report
System: The UNT Digital Library