On the unsteady-motion theory of magnetic forces for maglev (open access)

On the unsteady-motion theory of magnetic forces for maglev

Motion-dependent magnetic forces are the key elements in the study of magnetically levitated vehicle (maglev) system dynamics. This paper presents an experimental and analytical study that will enhance their understanding of the role of unsteady-motion-dependent magnetic forces and demonstrate an experimental technique that can be used to measure those unsteady magnetic forces directly. The experimental technique provides a useful tool to measure motion-dependent magnetic forces for the prediction and control of maglev systems.
Date: February 1, 1996
Creator: Chen, S.S.; Zhu, S. & Cai, Y.
Object Type: Report
System: The UNT Digital Library
TCP performance in ATM networks: ABR parameter tuning and ABR/UBR comparisons (open access)

TCP performance in ATM networks: ABR parameter tuning and ABR/UBR comparisons

This paper explores two issues on TOP performance over ATM networks: ABR parameter tuning and performance comparison of binary mode ABR with enhanced UBR services. Of the fifteen parameters defined for ABR, two parameters dominate binary mode ABR performance: Rate Increase Factor (RIF) and Rate Decrease Factor (RDF). Using simulations, we study the effects of these two parameters on TOP over ABR performance. We compare TOP performance with different ABR parameter settings in terms of through-puts and fairness. The effects of different buffer sizes and LAN/WAN distances are also examined. We then compare TOP performance with the best ABR parameter setting with corresponding UBR service enhanced with Early Packet Discard and also with a fair buffer allocation scheme. The results show that TOP performance over binary mode ABR is very sensitive to parameter value settings, and that a poor choice of parameters can result in ABR performance worse than that of the much less expensive UBR-EPD scheme.
Date: February 27, 1996
Creator: Chien Fang & Lin, A.
Object Type: Article
System: The UNT Digital Library
Optimization of a steam-assisted gravity drainage project in the Monarch sands of the south Midway-Sunset field (open access)

Optimization of a steam-assisted gravity drainage project in the Monarch sands of the south Midway-Sunset field

This report presents several scenarios for oil recovery optimization of Berry Petroleum Company`s properties in the Midway-Sunset field in Kern County, California. The primary goal was to evaluate reservoir performance with a number of vertical wells recompleted in the lower half of the existing oil bank and with a number of horizontal infill wells. Case comparisons and recommendations are based solely on oil production rates and cumulative oil production obtained from the simulations; no economic analyses were performed as part of this study. The results indicate that recompleting two thirds of the vertical wells in the lower half of the existing oil bank will give the most improvement in oil recovery. The models also show that accelerated oil recovery will be obtained from the horizontal well scenario (Case h3), with initial oil rates higher than the vertical well recompletion scenario (Case 3). However, in the long term (11 year period), the cumulative oil production of the horizontal well will fall below that of the vertical well recompletion scheme (Case h3 vs. Case 3). Additionally, a combination of horizontal wells with recompletion of 1/3 of the vertical wells will give a significant improvement in oil recovery (Case h8). We recommend that …
Date: February 1, 1996
Creator: Chona, R.A.; Hazlett, W.G. & Rajtar, J.M.
Object Type: Report
System: The UNT Digital Library
Evaluation of effects of LWR coolant environments on fatigue life of carbon and low-alloy steels (open access)

Evaluation of effects of LWR coolant environments on fatigue life of carbon and low-alloy steels

The ASME Boiler and Pressure Vessel Code provides rules for the construction of nuclear power plant components. Figure I-90 of Appendix I to Section III of the Code specifies fatigue design curves for structural materials. However, the effects of light water reactor (LWR) coolant environments are not explicitly addressed by the Code design curves. Recent test data indicate a significant decrease in fatigue life of carbon and low-alloy steels in LWR environments when five conditions are satisfied simultaneously, viz., applied strain range, temperature, dissolved oxygen in the water, and sulfur content of the steel are above a minimum threshold level, and the loading strain rate is below a threshold value. Only a moderate decrease in fatigue life is observed when any one of these conditions is not satisfied. This paper summarizes available data on the effects of various material and loading variables such as steel type, dissolved oxygen level, strain range, strain rate, and sulfur content on the fatigue life of carbon and low-alloy steels. The data have been analyzed to define the threshold values of the five critical parameters. Methods for estimating fatigue lives under actual loading histories are discussed.
Date: February 1, 1996
Creator: Chopra, O. K. & Shack, W. J.
Object Type: Article
System: The UNT Digital Library
Environmentally assisted cracking of light-water reactor materials (open access)

Environmentally assisted cracking of light-water reactor materials

Environmentally assisted cracking (EAC) of lightwater reactor (LWR) materials has affected nuclear reactors from the very introduction of the technology. Corrosion problems have afflicted steam generators from the very introduction of pressurized water reactor (PWR) technology. Shippingport, the first commercial PWR operated in the United States, developed leaking cracks in two Type 304 stainless steel (SS) steam generator tubes as early as 1957, after only 150 h of operation. Stress corrosion cracks were observed in the heat-affected zones of welds in austenitic SS piping and associated components in boiling-water reactors (BRWs) as early as 1965. The degradation of steam generator tubing in PWRs and the stress corrosion cracking (SCC) of austenitic SS piping in BWRs have been the most visible and most expensive examples of EAC in LWRs, and the repair and replacement of steam generators and recirculation piping has cost hundreds of millions of dollars. However, other problems associated with the effects of the environment on reactor structures and components am important concerns in operating plants and for extended reactor lifetimes. Cast duplex austenitic-ferritic SSs are used extensively in the nuclear industry to fabricate pump casings and valve bodies for LWRs and primary coolant piping in many PWRs. Embrittlement …
Date: February 1, 1996
Creator: Chopra, O. K.; Chung, H. M.; Kassner, T. F. & Shack, W. J.
Object Type: Article
System: The UNT Digital Library
Threshold properties of a microcavity laser with submicroampere threshold current (open access)

Threshold properties of a microcavity laser with submicroampere threshold current

We report the threshold characteristics of small oxide-confined vertical-cavity surface emitting lasers. Abrupt threshold transitions 105 times the spontaneous emission background are obtained at injection currents as low as 470 nanoampere.
Date: February 1, 1996
Creator: Choquette, K. D.; Hou, H. Q.; Lear, K. L.; Chow, W. W.; Mar, A.; Geib, K. M. et al.
Object Type: Article
System: The UNT Digital Library
Advances in oxide-confined vertical cavity lasers (open access)

Advances in oxide-confined vertical cavity lasers

We review the advances made in device fabrication, structure, and performance of vertical-cavity surface emitting lasers (VCSELs) which incorporate the selective oxidation of AlGaAs.
Date: February 1, 1996
Creator: Choquette, K. D.; Schneider, R. P., Jr.; Lear, K. L.; Geib, K. M.; Hou, H. Q.; Chui, H. C. et al.
Object Type: Article
System: The UNT Digital Library
Volt-time characteristics of short air gaps under nonstandard lightning voltage waves (open access)

Volt-time characteristics of short air gaps under nonstandard lightning voltage waves

The breakdown voltage level of a dielectric system under a transient voltage of a given waveshape is not a constant parameter. When transient voltages of the same waveshape but of increasing amplitude are applied to a dielectric system, the dielectric breaks down at higher voltage levels at shorter time delays for the higher applied voltages. This characteristic, known as the volt-time or time-lag characteristic, significantly influences the insulation coordination of an electric power system. The volt-time characteristics of 5-cm long rod-plane and rod-rod air gaps were experimentally determined with five different waveshapes of the applied impulse voltage. The front time of the waves was varied from 25 ns to 10 {micro}s, and the time to half value was varied from 0.5 {micro}s to 100 {micro}s. The volt-time characteristics were also checked analytically using the concept of disruptive effect. The parameters for the disruptive effect were experimentally determined.
Date: February 1996
Creator: Chowdhuri, P.; Mishra, A. K. & McConnell, B. W.
Object Type: Article
System: The UNT Digital Library
Properties of vanadium-base alloys irradiated in the dynamic helium charging experiment (open access)

Properties of vanadium-base alloys irradiated in the dynamic helium charging experiment

One property of vanadium-base alloys that is not well understood in terms of their potential use as fusion reactor structural materials is the effect of simultaneous generation of helium and neutron damage. In the present Dynamic Helium Charging Experiment (DHCE), helium was produced uniformly in the specimen at linear rates of {approx} 0.4 to 4.2 appm helium/dpa by the decay of tritium during irradiation to 18--31 dpa at 425--600 C in Li-filled capsules in a sodium-cooled fast reactor. This paper presents results of postirradiation examination and tests of microstructure and mechanical properties of V-5Ti, V-3Ti-1Si, V-8Cr-6Ti, and V-4Cr-4Ti (the latter alloy has been identified as the most promising candidate vanadium alloy). Effects of helium on tensile strength and ductility were insignificant after irradiation and testing at > 420 C. However, postirradiation ductilities at < 250 C were higher than those of the non-DHCE specimens (< 0.1 appm helium), whereas strengths were lower, indicating that different types of hardening centers are produced during DHCE and non-DHCE irradiation. Ductile-brittle transition behavior of the DHCE specimens was also determined from bend tests and fracture appearance of transmission electron microscopy (TEM) disks and broken tensile specimens. No brittle behavior was observed at temperatures > …
Date: February 1, 1996
Creator: Chung, H. M.; Loomis, B. A. & Smith, D. L.
Object Type: Report
System: The UNT Digital Library
WATER SUPPLY ANALYSIS (open access)

WATER SUPPLY ANALYSIS

This analysis defines and evaluates the surface water supply system from the existing J-13 well to the North Portal. This system includes the pipe running from J-13 to a proposed Booster Pump Station at the intersection of H Road and the North Portal access road. Contained herein is an analysis of the proposed Booster Pump Station with a brief description of the system that could be installed to the South Portal and the optional shaft. The tanks that supply the water to the North Portal are sized, and the supply system to the North Portal facilities and up to Topopah Spring North Ramp is defined.
Date: February 6, 1996
Creator: Clark, R.D.
Object Type: Report
System: The UNT Digital Library
Numerical simulation of the laminar diffusion flame in a simplified burner. Revision 1 (open access)

Numerical simulation of the laminar diffusion flame in a simplified burner. Revision 1

The laminar ethylene-air diffusion flame in a simple laboratory burner was simulated with the COYOTE reactive flow program. This program predicts the flow field, transport, and chemistry for the purposes of code validation and providing physical understanding of the processes occurring in the flame. The authors show the results of numerical experiments to test the importance of several physical phenomena, including gravity, radiation, and differential diffusion. The computational results compare favorably with the experimental measurements, and all three phenomena are important to accurate simulations.
Date: February 1, 1996
Creator: Cloutman, L.D.
Object Type: Article
System: The UNT Digital Library
Plasma diagnostic reflectometry (open access)

Plasma diagnostic reflectometry

Theoretical and experimental studies of plasma diagnostic reflectometry have been undertaken as a collaborative research project between the Lawrence Livermore National Laboratory (LLNL) and the University of California Department of Applied Science Plasma Diagnostics Group under the auspices of the Laboratory Directed Research and Development Program at LLNL. Theoretical analyses have explored the basic principles of reflectometry to understand its limitations, to address specific gaps in the understanding of reflectometry measurements in laboratory experiments, and to explore extensions of reflectometry such as ultra-short-pulse reflectometry. The theory has supported basic laboratory reflectometry experiments where reflectometry measurements can be corroborated by independent diagnostic measurements.
Date: February 26, 1996
Creator: Cohen, B. I.; Afeyan, B. B.; Garrison, J. C.; Kaiser, T. B.; Luhmann Jr. N. C.; Domier, C. W. et al.
Object Type: Report
System: The UNT Digital Library
Alpha contamination assessment for D&D activities: Technology overview (open access)

Alpha contamination assessment for D&D activities: Technology overview

Instruments based on the principle of Long-Range Alpha Detection (LRAD) detect the ions created in ambient air by Ionizing radiation, particularly alpha radiation, interacting with air molecules. Using either an electrostatic field or forced convection, these ions can be transported to a detection grid where the ions produce a small current that is measured with a sensitive electrometer. LRAD-based instruments can give separate, simultaneous measurements of alpha-emitting solids and inert radioactive gases such as radon. LRAD-based instruments assess surface contamination on an entire object or large surface area in a single, rapid measurement, including relatively inaccessible areas such as interior surfaces of pipes and process equipment. The LRAD concept is well proven and has been developed into a range of different radiation detection devices. This paper presents an overview of the technology, while several associated papers explore specific applications in greater detail.
Date: February 1, 1996
Creator: Conaway, J.G.; Rawool-Sullivan, M.W. & MacArthur, D.W.
Object Type: Report
System: The UNT Digital Library
US hydropower resource assessment for Vermont (open access)

US hydropower resource assessment for Vermont

The Department of Energy is developing an estimate of the undeveloped hydropower potential in this country. The Hydropower Evaluation Software is a computer model that was developed by the Idaho National Engineering Laboratory for this purpose. The software measures the undeveloped hydropower resources available in the United States, using uniform criteria for measurement. The software was developed and tested using hydropower information and data provided by the Southwestern Power Administration. It is a menu-driven software program that allows the personal computer user to assign environmental attributes to potential hydropower sites, calculate development suitability factors for each site based on the environmental attributes present, and generate reports based on these suitability factors. This report details the resource assessment results for the State of Vermont.
Date: February 1, 1996
Creator: Conner, A. M. & Francfort, J. E.
Object Type: Report
System: The UNT Digital Library
Uniform criteria for U.S. hydropower resource assessment: Hydropower Evaluation Software status report -- 2 (open access)

Uniform criteria for U.S. hydropower resource assessment: Hydropower Evaluation Software status report -- 2

The US Department of Energy is estimating the undeveloped hydropower potential in the US. The Hydropower Evaluation software is a computer model that was developed by the Idaho National Engineering Laboratory for this purpose. The Hydropower Evaluation Software estimates the undeveloped hydropower resources available in the US, using uniform criteria for measurement. The software was developed and tested using hydropower information and data provided by the Southwestern Power Administration. It is a menu-driven software application. Hydropower Evaluation Software allows the personal computer user to assign environmental attributes to potential hydropower sites, calculate development suitability factors for each site based on the environmental attributes present, and generate reports based on these suitability factors. This status report describes Hydropower Evaluation Software`s development, its data requirements, and its application to the 20 states assessed to date. This report does not discuss or present the various user-friendly menus of the Hydropower Evaluation Software. The reader is referred to the User`s Manual for specifics. This report focuses on data derivation, summarization of the 20 states (Arkansas, Missouri, Montana, New Hampshire, North Dakota, Oklahoma, Rhode Island, South Dakota, Texas, Utah, Vermont, and Wyoming) assessed to date, and plans for future assessments.
Date: February 1, 1996
Creator: Conner, A. M.; Francfort, J. E. & Rinehart, B. N.
Object Type: Report
System: The UNT Digital Library
Final report for tank 241-BX-112, auger samples 95-Aug-047 and 95-Aug-048 (open access)

Final report for tank 241-BX-112, auger samples 95-Aug-047 and 95-Aug-048

This document serves as the final report for Tank 241-BX-112. The auger samples were taken on Nov. 16 and 17, 1995. The report is broken into 2 parts; the nd part consists of the original 45-day safety screening report (including the DSC and TGA raw data). Prior to auger sampling, the vapor space of tank BX-112 was screened for flammability issues; the vapor space was found to be far below the lower explosive limit. The auger samples were taken to fully satisfy the DQO.
Date: February 29, 1996
Creator: Conner, J.M.
Object Type: Report
System: The UNT Digital Library
Modifying the CERN SWC cavities and amplifiers for use in RHIC (open access)

Modifying the CERN SWC cavities and amplifiers for use in RHIC

None
Date: February 1, 1996
Creator: Connolly, R.; Aspenleiter, J. & Kwiatkowski, S.
Object Type: Report
System: The UNT Digital Library
Atmospheric carbon diooxide mixing ratios from the NOAA Climate Monitoring and Diagnostics Laboratory cooperative flask sampling network, 1967-1993 (open access)

Atmospheric carbon diooxide mixing ratios from the NOAA Climate Monitoring and Diagnostics Laboratory cooperative flask sampling network, 1967-1993

This data report documents monthly atmospheric CO{sub 2} mixing ratios and measurements obtained by analyzing individual flask air samples for the NOAA/CMDL global cooperative flask sampling network. Measurements include land-based sampling sites and shipboard measurements covering 14 latitude bands in the Pacific Ocean and South China Sea. Analysis of the NOAA/CMDL flask CO{sub 2} database shows a long-term increase in atmospheric CO{sub 2} mixing ratios since the late 1960s. This report describes how the samples are collected and analyzed and how the data are processed, defines limitations, and restrictions of the data, describes the contents and format of the data files, and provides tabular listings of the monthly carbon dioxide records.
Date: February 1, 1996
Creator: Conway, T. J.; Tans, P. P. & BBoden, T. A.
Object Type: Report
System: The UNT Digital Library
CO{sub 2} dial transmitter/receiver noise characterization and related correlated noise issues (open access)

CO{sub 2} dial transmitter/receiver noise characterization and related correlated noise issues

Our approach concerning the development of hard target return CO{sub 2} DIAL transmitter/receiver systems is two phased- (i) through analysis and experiment, develop a fundamental understanding of the transmitter/receiver physics specific to DIAL systems and (ii) apply these fundamentals in the development of optimal performance DIAL transmitter/receiver systems. We present our progress and results towards these objectives with the following topics addressed: A general overview of the DIAL transmitter/receiver system characterization effort with a focus on transceiver noise processes. The effects of correlated noise on DIAL performance, especially those effecting statistical convergence over long sample structures, is , introduced. And, preliminary measurements of a low-noise, ``white`` receiver prototype are presented.
Date: February 1, 1996
Creator: Cooke, B.; Schmitt, M.; Goeller, R.; Czuchlewski, S.; Fuller, K.; Olivas, N. et al.
Object Type: Article
System: The UNT Digital Library
Design review report for rotary mode core sample truck (RMCST) modifications for flammable gas tanks, preliminary design (open access)

Design review report for rotary mode core sample truck (RMCST) modifications for flammable gas tanks, preliminary design

This report documents the completion of a preliminary design review for the Rotary Mode Core Sample Truck (RMCST) modifications for flammable gas tanks. The RMCST modifications are intended to support core sampling operations in waste tanks requiring flammable gas controls. The objective of this review was to validate basic design assumptions and concepts to support a path forward leading to a final design. The conclusion reached by the review committee was that the design was acceptable and efforts should continue toward a final design review.
Date: February 1, 1996
Creator: Corbett, J.E.
Object Type: Report
System: The UNT Digital Library
309 Facility deactivation and decommisioning Criteria Completion Check Lists (open access)

309 Facility deactivation and decommisioning Criteria Completion Check Lists

To facilitate and track completion of the 309 Facility turnover criteria completion an Applicability Matrix and Criteria Completion Check Lists were prepared. The applicability matrix documents the required turnover criteria for a given area in the facility or scope of work. The applicable criteria is selected for 16 different areas. For each area a completion checklist is provided to document completion of a requirement by WHC and the Environmental Restoration Contractor.
Date: February 1, 1996
Creator: Cornwell, B.C.
Object Type: Report
System: The UNT Digital Library
Mercury retorting of calcine waste, contaminated soils and railroad ballast at the Idaho National Egineering Laboratory (open access)

Mercury retorting of calcine waste, contaminated soils and railroad ballast at the Idaho National Egineering Laboratory

The Idaho National Engineering Laboratory (INEL) has been involved in nuclear reactor research and development for over 40 years. One of the earliest major projects involved the development of a nuclear powered aircraft engine, a long-term venture which used mercury as a shielding medium. Over the course of several years, a significant amount of mercury was spilled along the railroad tracks where the test engines were transported and stored. In addition, experiments with volume reduction of waste through a calcine process employing mercury as a catalyst resulted in mercury contaminated calcine waste. Both the calcine and Test Area North wastes have been identified in Department of Energy Action Memorandums to be retorted, thereby separating the mercury from the various contaminated media. Lockheed Idaho Technologies Company awarded the Mercury Retort contract to ETAS Corporation and assigned Parsons Engineering Science, Inc. to manage the treatment field activities. The mercury retort process entails a mobile unit which consists of four trailer-mounted subsystems requiring electricity, propane, and a water supply. This mobile system demonstrates an effective strategy for retorting waste and generating minimal secondary waste.
Date: February 28, 1996
Creator: Cotten, G. B.; Rothermel, J. S.; Sherwood, J.; Heath, S. A. & Lo, T. Y. R.
Object Type: Article
System: The UNT Digital Library
Extents of alkane combustion during rapid compression leading to single and two stage ignition (open access)

Extents of alkane combustion during rapid compression leading to single and two stage ignition

Extents of reactant consumption have been measured during the course of spontaneous ignition following rapid compression of N-pentane and N-heptane and also of PRF 60 (N-heptane = i-octane, 2.2.4 trimethylpentane) in stoichiometric mixtures with air. Compressed gas temperatures of 720-750 K and 845-875 K were studied at reactant densities of 131 mol m{sup minus 3}. At the lower gas temperature there was no evidence of reactant consumption during the course of the compression stroke. Two-stage ignition occurred at these temperatures, but only modest proportions of n-pentane were consumed during the first stage (< 15%) whereas about 40% of proportions of n- heptane reacted under the same conditions. At the higher compressed gas temperature the oxidation of n-pentane began only after the piston had stopped, whereas more than 30% of the n-heptane had already been consumed in the final stage of the compression stroke. The behavior of the PRF 60 mixture differed somewhat from that of N- pentane despite the similarly of the research octane numbers. Although there was a preferential oxidation of n-heptane at T{sub c} = 850K, which persisted throughout the early development of spontaneous ignition during the post-compression period, oxidation of both components of the PRF 60 mixture …
Date: February 1, 1996
Creator: Cox, A.; Griffiths, J. F.; Mohamed, C.; Curran, H.; Pitz, W. J. & Westbrook, C. K.
Object Type: Article
System: The UNT Digital Library
Sample Preparation of Tank 241-C-106 Grab Samples and Testing for Compatibility With Tank 241-AY-102 Supernate (open access)

Sample Preparation of Tank 241-C-106 Grab Samples and Testing for Compatibility With Tank 241-AY-102 Supernate

This test plan describes a sample separation method which will be used to obtain physical measurements and separated 241-C-106 solids and supernate fractions. In addition compatibility of tank 241-C-106 sludge with tank 241-AY-102 supernate will be determined.
Date: February 23, 1996
Creator: Crawford, B. A.
Object Type: Report
System: The UNT Digital Library