UNT Libraries Government Documents Department - 28 Matching Results

Search Results

An Adaptive Finite Difference Method for Hyperbolic Systems in OneSpace Dimension

Description: Many problems of physical interest have solutions which are generally quite smooth in a large portion of the region of interest, but have local phenomena such as shocks, discontinuities or large gradients which require much more accurate approximations or finer grids for reasonable accuracy. Examples are atmospheric fronts, ocean currents, and geological discontinuities. In this thesis we develop and partially analyze an adaptive finite difference mesh refinement algorithm for the initial boundary value problem for hyperbolic systems in one space dimension. The method uses clusters of uniform grids which can ''move'' along with pulses or steep gradients appearing in the calculation, and which are superimposed over a uniform coarse grid. Such refinements are created, destroyed, merged, separated, recursively nested or moved based on estimates of the local truncation error. We use a four-way linked tree and sequentially allocated deques (double-ended queues) to perform these operations efficiently. The local truncation error in the interior of the region is estimated using a three-step Richardson extrapolation procedure, which can also be considered a deferred correction method. At the boundaries we employ differences to estimate the error. Our algorithm was implemented using a portable, extensible Fortran preprocessor, to which we added records and pointers. The method is applied to three model problems: the first order wave equation, the second order wave equation, and the inviscid Burgers equation. For the first two model problems our algorithm is shown to be three to five times more efficient (in computing time) than the use of a uniform coarse mesh, for the same accuracy. Furthermore, to our knowledge, our algorithm is the only one which adaptively treats time-dependent boundary conditions for hyperbolic systems.
Date: June 1, 1982
Creator: Bolstad, John H.

Advanced Fuel Cell Development Progress Report: October-December 1980

Description: Quarterly report discussing fuel cell research and development work at Argonne National Laboratory (ANL). This report describes efforts directed toward (1) developing alternative concepts for components of molten carbonate fuel cells and (2) improving understanding of component behavior.
Date: June 1982
Creator: Pierce, R. D.; Arons, R. M.; Dusek, J. T.; Fraioli, A. V.; Kucera, G. H.; Sim, J. W. et al.

Agent Orange: Veterans' Complaints Concerning Exposure to Herbicides in South Vietnam

Description: From 1962 to 1971, the United States Air Force (USAF) sprayed various herbicide mixtures (chemicals that kill plants) in South Vietnam. The purpose of the spraying was to defoliate jungle growth to deprive the Communist forces of ground cover, and to destroy enemy crops to restrict food supplies. The most extensively used of these herbicide mixtures was known as Agent Orange, a 50:50 mix of two common herbicides called 1,4,5-T and 2,4-D (2,4,5-trichlorophenoxyacetic acid and 2,4-dichlorophenoxyacetic acid). The third chemical present in the mixture in small amounts was TCDD, an inevitable by-product of the manufacture of 2,4,5-T. This chemical, called tetrachlorodibenzo-para-dioxin or simply "dioxin," is highly toxic to laboratory animals when administered in its pure form. CRS has been unable to locate any report of a human death from exposure to pure TCDD. This report discusses the human health effects that have occurred from exposure to TCDD, as well as related Congressional concerns.
Date: June 25, 1982
Creator: Smith, Pamela W.

ANL Micrometeorological Measurements of Particle Sulfur Deposition at the 1981 Dry Deposition Intercomparison Experiment.

Description: The Dry Deposition Intercomparison Experiment conducted in September, 1981, was designed by the Illinois State Water Survey as a pilot effort to evaluate various methods of measuring pollutant dry deposition. A more extensive experiment was planned for June, 1982, when additional and improved techniques were to be implemented. The 1981 study focused on sulfate aerosol, while the 1982 experiment will consider a wider range of particulate substances and some gases. At issue is whether traditional monitoring methods using surrogate surfaces to collect dry deposition can routinely provide estimates in agreement with results from applications of intensive micrometeorological techniques. This report summarizes the micrometeorological data gathered in 1981 by Argonne National Laboratory.
Date: June 30, 1982
Creator: Wesely, M. L.; Cook, D. R. & Hart, R. L.

Civilian Space Policy and Applications

Description: A report by the Office of Technology Assessment (OTA) that evaluates "the present states and possible future directions of space applications technologies in the civilian sector" and focuses on the technologies of "satellite communications, land remote sensing, materials processing in space, and space transportation" (p. iii).
Date: June 1982
Creator: United States. Congress. Office of Technology Assessment.

A Coupled Heat Conduction and Thermal Stress Formulation Using Explicit Integration

Description: The formulation needed for the conductance of heat by means of explicit integration is presented. The implementation of these expressions into a transient structural code, which is also based on explicit temporal integration, is described. Comparisons of theoretical results with code predictions are given both for one-dimensional and two-dimensional problems. The coupled thermal and structural solution of a concrete crucible, when subjected to a sudden temperature increase, shows the history of cracking. The extent of cracking is compared with experimental data.
Date: June 1982
Creator: Marchertas, A. H. & Kulak, R. F.

Development of Enhanced Heat Transfer/Transport/Storage Slurries for Thermal-System Improvement

Description: This report constitutes a formulation of a new concept for improving thermal-system performance by utilizing the combined mechanisms of enhanced heat transfer, transport, and thermal energy storage associated with a phase-change slurry as the working fluid. In addition, pertinent literature is surveyed and a quantitative scoping assessment of enhancement potential confirms concept merit. It has been determined that additional research and development is required in order to adequately understand the enhancement mechanisms to the degree that enhanced performance thermal systems using slurries can be designed. The concepts presented are identified as being new, rewarding research activities.
Date: June 1982
Creator: Kasza, Kenneth Edmund & Chen, M. M.

Division of Biological and Medical Research Annual Technical Report 1981

Description: This report summarizes research during 1981 in the Division of Biological and Medical Research, Argonne National Laboratory. Studies in Low Level Radiation include comparison of lifetime effects in mice of low level neutron and gamma irradiation, delineation of the responses of dogs to continuous low level gamma irradiation, elucidation of mechanisms of radiation damage and repair in mammalian cells, and study of the genetic effects of high LET radiations.
Date: June 1982
Creator: Argonne National Laboratory. Division of Biological and Medical Research.

Effects of Water Injection into Fractured Geothermal Reservoirs: A Summary of Experience Worldwide

Description: Reinjection of water into fractured geothermal reservoirs holds potential both for improvement and degradation of total energy recovery. The replacement of reservoir fluid can mean support of placement of reservoir pressures and also more efficient thermal energy recovery, but at the same time the premature invasion of reinjected water back into production wells through high permeability fractures can reduce discharge enthalpy and hence deliverability and useful energy output. Increases in reservoir pressure and maintenance of field output have been observed in operating fields, but unfortunately so too have premature thermal breakthroughs. The design of reinjection schemes, therefore, requires careful investigation into the likely effects, using field experimentation. This paper summarizes field experience with reinjection around the world, with the intention of elucidating characteristics of possible problems. The results summarized in this paper fall into three categories of interest: permeability changes dye to injection (both increases and decreases); the path followed by injected water (as indicated by tracer tests); and the thermal and hydraulic influences of injection on the reinjection well itself and on surrounding producers. [DJE-2005]
Date: June 1, 1982
Creator: Horne, Roland N.


Description: The primary objective of this program was the evaluation of acoustical holography techniques for characterization of the light water reactor weld surface signatures in the nuclear safeguards program. The accurate characterization of weld surface irregulari ties and vertical deviations was achieved using acoustical holographic interferometric techniques. Preselected weld surfaces were inspected and the vertical deviations characterized by phase measurements or fringe densities in the image. Experimental results on Sandia samples verify depth deviation sensitivities of 0.11 {micro}m to 0.16 {micro}m. The two point interferogram technique is recommended for surveillance of the weld surface associated wi th fuel rod removal in the nuclear safeguard program. The use of this unique holographic signal processing provides essentially a fail-safe method for surveillance of clandestine fuel rod removal. Statistical analysis indicates 99.99% (weld surface deviation) confidence interval between 2~m and 3~m can be achieved. These results illustrate the extremely high resolution capabilities of the surveillance technique employing coherent signal processing.
Date: June 1, 1982
Creator: Collins, H. D. & Gribble, R. P.

Flat-Rate Tax Proposals

Description: In recent months there has been a growing congressional interest in the advantages and disadvantages of revamping our current tax system for a flat-rate tax method. Supporters of the new proposal argue that such a plan would promote productivity, simplify present IRS tax forms, save the public billions of dollars that presently go to tax-preparation professionals, and enhance Federal revenue by closing numerous tax loopholes and special deductions that are now enjoyed by relatively few. Opponents believe, however, that the tax burden under a flat-rate plan might fall more heavily upon the middle class and, unless exceptions were made, would hurt educational institutions and charities. Problems with popular tax deductions, such as home mortgage interest, would have to be addressed. This packet provides background materials which discuss the practical and theoretical issues that surround a flat-rate tax, including the probable redistribution of the tax burden under various rates and income bases.
Date: June 21, 1982
Creator: Esenwein, Gregg A.

High Burnup Effects Program A State-of-the-Technology Assessment

Description: Various analytical models and empirical correlations describing the fission gas release phenomenon were examined. An evaluation was made of the current pertinent experimental data on the subject of high burnup fission gas release. Data reported by individual investigators were compared and evaluated in relation to their applicability to the content and scope of the High Burnup Effects Program. These evaluations then form the bases for defining the data needs, and the selection of variables to be studied in this program.
Date: June 1, 1982
Creator: Rising, K. H.; Bradley, E. R.; Williford, R. E. & Freshley, M D.

Laboratory studies of radionuclide transport in fractured Climax granite

Description: This report documents our laboratory studies of radionuclide transport in fractured granite cores. To simulate natural conditions, our laboratory studies used naturally fractured cores and natural ground water from the Climax Granite Stock at the Nevada Test Site. For comparison, additional tests used artificially fractured granite cores or distilled water. Relative to the flow of tritiated water, {sup 85}Sr and /sup 95m/Tc showed little or no retardation, whereas {sup 137}Cs was retarded. After the transport runs the cores retained varying amounts of the injected radionuclides along the fracture. Autoradiography revealed some correlation between sorption and the fracture fill material. Strontium and cesium retention increased when the change was made from natural ground water to distilled water. Artificial fractures retained less {sup 137}Cs than most natural fractures. Estimated fracture apertures from 18 to 60 {mu}m and hydraulic conductivities from 1.7 to 26 x 10{sup -3} m/s were calculated from the core measurements.
Date: June 1, 1982
Creator: Failor, R.; Isherwood, D.; Raber, E. & Vandergraaf, T.

Measurement of Electrical Quantities in Pulse Power Systems

Description: Abstract: The Workshop on Measurement of Electrical Quantities in Pulse Power Systems addressed measurements in pulse systems having the characteristics of pulse duration less than a millisecond, system voltages greater than 10 kilovolts, and system currents greater than 10 kiloamperes. The presented papers were divided into four categories: voltage measurements; current measurements; power and energy measurements, and data acquisition. Included are discussions of applications of conventional measurement techniques and state-of-the-art systems.
Date: June 1982
Creator: McKnight, R. H. & Hebner, R. E., Jr.

Nevada Nuclear Waste Storage Investigations: exploratory shaft. Phase I. Conceptual design report

Description: It is proposed that an Exploratory Shaft (ES) be constructed in Yucca Mountain on or near the southwest portion of the Nevada Test Site (NTS) as part of the Nevada Nuclear Waste Storage Investigations. This document describes a conceptual design for an ES and a cost estimate based on a set of construction assumptions. Included in this document are appendixes consisting of supporting studies done at NTS by Fenix and Scisson, Inc. and Holmes and Narver, Inc. These appendixes constitute a history of the development of the design and are included as part of the record.
Date: June 1, 1982
Creator: Nelson, D.C.; Merson, T.J.; McGuire, P.L. & Sibbitt, W.L.

Permeability change near instrumentation holes in jointed rock: implications for the tuff radionuclide-migration field experiment

Description: In order to assess in situ joint permeability near waste repositories, it has been proposed that instrumentation holes with axes parallel to the joint plane be drilled. However, the drill holes after the normal stress across the joint. The resultant stress concentration decreases the joint aperture and can significantly affect the joint permeability. Different intersections of the hold axis relative to the joint plane were examined utilizing a plane-strain, elastic analysis. It was found that a tangential joint intersection minimized the normal stress change. Stress along the joint increased by 10 to 15 percent and the permeability-aperture product decreased to 65 to 70 percent of its original flow.
Date: June 1, 1982
Creator: Rechard, R.P. & Schuler, K.W.

Physics Division Annual Review, 1 April 1980-31 March 1981

Description: The Physics Division's program in nuclear physics covers a broad span of activities within that discipline. The object of this research is to understand the properties of atomic nuclei, their structure, the mechanisms of nuclear reactions, and manifestations of fundamental symmetries in nuclei. Work is carried out under a variety of subprograms: theory, heavy-ion physics, medium-energy physics and nuclear research. These categories do not represent a sharp separation between people--individual scientists often work in several different areas. This flexibility allows scientific problems to be addressed with a variety of techniques, and it avoids limiting individual scientists' activities to a particular subdiscipline.
Date: June 1982
Creator: Schiffer, John P.

Proposal to study stem forgings

Description: Reservoir designs consist of two primary features including the stem(s) and the body segment. The stem is either an integral part of the reservoir or is joined at some point in the fabrication sequence. The current interest is in high strength stems for advanced reservoir designs. The processing necessary to achieve these strength levels may result in heavily cold worked microstructures which may not interface well with the stem requirements. For instance, cold worked 316 plate stock has shown decreased hydrogen compatibility when contrasted to the annealed version in laboratory tests. More recently, Precision Forge produced a 100 ksi yield strength, 304L stem forging with a heavily deformed microstructure which also may show decreased compatibility in hydrogen. The proposed forging contract will evaluate the influence of forging parameters on the microstructure and mechanical properties of 304L and 316 stem forgings. A summary of the data available on 304L stem forgings is shown graphically. The yield strength values are shown for each set of forging parameters. Tensile tests and microstructural examination will be conducted to complete the information for 304L and create a similar graph for 316 stem forgings.
Date: June 25, 1982
Creator: Odegard, B.C.