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ADIFOR: Fortran source translation for efficient derivatives

Description: The numerical methods employed in the solution of many scientific computing problems require the computation of derivatives of a function f: R{sup n} {yields} R{sup m}. Both the accuracy and the computational requirements of the derivative computation are usually of critical importance for the robustness and speed of the numerical method. ADIFOR (Automatic Differentiation In FORtran) is a source translation tool implemented using the data abstractions and program analysis capabilities of the Pa… more
Date: January 1, 1992
Creator: Bischof, C.; Corliss, G.; Griewank, A.; Hovland, P. (Argonne National Lab., IL (United States)) & Carle, A. (Rice Univ., Houston, TX (United States). Center for Research on Parallel Computation)
Partner: UNT Libraries Government Documents Department
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Flow instability in a vertical annulus under steady state and transient conditions

Description: Experimental data have been obtained for the occurrence of flow instability in a vertical annulus under steady state and transient down-flow conditions. The results show that the primary factor affecting the onset of flow instability is the Q{sub ratio} parameter (a measure of the void production in a channel). In addition, it is shown that for steady state conditions good agreement exists between the single annulus data and single tube data based upon the same L/D ratio. The results also indic… more
Date: January 1, 1992
Creator: Fighetti, C.; Kokolis, S.; Maciuca, C.; Reddy, D.G.; Yang, B.; Carrano, V. (Columbia Univ., New York, NY (United States)) et al.
Partner: UNT Libraries Government Documents Department
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A conceptual framework for using DOE 5700. 6C and the other DOE orders as an integrated management system; the Fermilab experience

Description: In this paper, I describe a conceptual framework that uses DOE Order 5700.6C and more than 140 other DOE Orders as an integrated management system -- but I describe it within the context of the broader sociological and cultural issues of doing research at DOE funded facilities. The conceptual framework has two components. The first involves an interpretation of the 10 criteria of DOE 5700.6C that is tailored for a research environment. The second component involves using the 10 criteria as func… more
Date: June 1, 1992
Creator: Bodnarczuk, M.
Partner: UNT Libraries Government Documents Department
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Open problems in sub-barrier fusion

Description: Two aspects of sub-barrier fusion are discussed. A challenge to the use of fission fragment angular distributions to probe the spin distribution in fusion is addressed. Evidence from excitation functions for the importance of neutron transfer and the neck degree of freedom is examined.
Date: January 1, 1992
Creator: Vandenbosch, R.
Partner: UNT Libraries Government Documents Department
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The potential of passive-remote Fourier transform infrared (FTIR) spectroscopy to detect organic emissions under the Clean Air Act

Description: The Clean Air Act of 1990 regulates the emission of 198 air toxics. Currently, there is no existing technology by which a regulatory agency can independently determine if a facility is in compliance. We have successfully tested the ability of passive-remote Fourier transform infrared (FTIR) spectroscopy to detect chemical plumes released in the field. Additional laboratory releases demonstrated that FTIR spectroscopy can detect target analytes in mixtures containing components which have overla… more
Date: January 1, 1992
Creator: Demirgian, J.C.; Hammer, C.L. (Argonne National Lab., IL (United States)) & Kroutil, R.T. (Chemical Research, Development and Engineering Center, Aberdeen Proving Ground, MD (United States))
Partner: UNT Libraries Government Documents Department
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Microscopic calculations of nuclear structure and nuclear correlations

Description: A major goal in nuclear physics is to understand how nuclear structure comes about from the underlying interactions between nucleons. This requires modelling nuclei as collections of strongly interacting particles. Using realistic nucleon-nucleon potentials, supplemented with consistent three-nucleon potentials and two-body electroweak current operators, variational Monte Carlo methods are used to calculate nuclear ground-state properties, such as the binding energy, electromagnetic form factor… more
Date: January 1, 1992
Creator: Wiringa, R.B.
Partner: UNT Libraries Government Documents Department
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Polarization phenomena in projectile fragmentation process

Description: The nuclear spin polarization of beta-emitting fragments {sup 37}K and {sup 39} Ca has been measured at around the grazing angle of the {sup 40}Ca + Au collision at 106 MeV/u. Momentum dependence of the observed fragment polarization supports the idea that the origin of the polarization is the orbital angular momentum held by the fragment part of the projectile before the collision takes place. The sizable polarization of about 5% that was observed for the fragments will be a powerful tool for … more
Date: March 1, 1992
Creator: Matsuta, K.; Ozawa, A.; Nojiri, Y.; Minamisono, T.; Fukuda, M.; Kitagawa, A. et al.
Partner: UNT Libraries Government Documents Department
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Physics at TeV e sup + e sup minus linear colliders

Description: A survey is presented of the physics opportunities at TeV e{sup +}e{sup {minus}} linear colliders. Examples are given of physics that might emerge in e{sup +}e{sup {minus}} collisions and in {gamma}{gamma} collisions using the back-scattered laser technique, including {gamma}{gamma} {yields} ZZ scattering as a probe of ultraheavy quanta. The second portion of the talk focuses on physics that must emerge at or below the TeV scale--the mechanism of electroweak symmetry breaking. In particular a v… more
Date: January 1, 1992
Creator: Chanowitz, Michael S.
Partner: UNT Libraries Government Documents Department
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Development and testing of an air quality model for Mexico City

Description: Los Alamos National Laboratory and Instituto Mexicano del Petroleo have embarked on a joint study of options for improving air quality in Mexico City. The intent is to develop a modeling system which can address the behavior of pollutants in the region so that option for improving Mexico City air quality can be properly evaluated. In February of 1991, the project conducted a field program which yielded a variety of data which is being used to evaluate and improve the models. Normally the worst … more
Date: March 2, 1992
Creator: Williams, M. D.; Streit, G. (Los Alamos National Lab., NM (United States)); Cruz, X.; Ruiz, M.; Sosa, G. (Instituto Mexicano de Petroleo, Mexico City (Mexico)); Russell, A. G. et al.
Partner: UNT Libraries Government Documents Department
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A formula for efficiency of fast wave current drive in fusion devices

Description: Fast wave current drive (FWCD) is a principal candidate for non- inductive current drive schemes in reactors. Major experiments are in progress or planned on DIII-D, JET, and Tore-Supra. A theory for FWCD was presented by two of the authors and collaborators. To minimize computations required in transport simulations, and for analytical understanding, it is very useful to have a concise analytical efficiency formula. Fisch and Karney, and Ehst and Karney have obtained empirical formulae that fi… more
Date: June 1, 1992
Creator: Chiu, S. C.; Harvey, R. W. (General Atomics, San Diego, CA (United States)); Karney, C. F. F. (Princeton Univ., NJ (United States). Plasma Physics Lab.) & Mau, T. K. (California Univ., Los Angeles, CA (United States). School of Engineering and Applied Science)
Partner: UNT Libraries Government Documents Department
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The influence of anharmonic phonons on the isotope effect in high- Tc oxides

Description: Anharmonic phonons are examined to study the unusual isotope effect exponents for the high-{Tc} oxides. Within a simple model of anharmonicity, the mass dependences of the electron-phonon coupling constant {lambda} and the phonon frequency determine the isotope effect exponent {alpha} as a function of coupling strength. A model in which the outer wells of a multiple-well potential deepen as the orthorhombic/low temperature tetragonal phase transition in La{sub 2-x}M{sub x}CuO{sub 4} is approach… more
Date: January 1, 1992
Creator: Crespi, V.H. & Cohen, M.L.
Partner: UNT Libraries Government Documents Department
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MHTGR thermal performance envelopes: Reliability by design

Description: This document discusses thermal performance envelopes which are used to specify steady-state design requirements for the systems of the Modular High Temperature Gas-Cooled Reactor to maximize plant performance reliability with optimized design. The thermal performance envelopes are constructed around the expected operating point accounting for uncertainties in actual plant as-built parameters and plant operation. The components are then designed to perform successfully at all points within the … more
Date: May 1, 1992
Creator: Etzel, K.T.; Howard, W.W. & Zgliczynski, J.B.
Partner: UNT Libraries Government Documents Department
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The IGAC activity for the development of global emissions inventories: Description and initial results

Description: Modeling assessments of the atmospheric chemistry, air quality and climatic conditions of the past, present and future require as input inventories of emissions of the appropriate chemical species constructed on appropriate spatial and temporal scales. The task of the Global Emissions Inventories Activity (GEIA) of the International Global Atmospheric Chemistry Project (IGAC) is the production of global inventories suitable for a range of research applications. Current GEIA programs are general… more
Date: February 1, 1992
Creator: Benkovitz, C.M. (Brookhaven National Lab., Upton, NY (United States)) & Graedel, T.E. (AT and T Bell Labs., Murray Hill, NJ (United States))
Partner: UNT Libraries Government Documents Department
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Considerations in recycling contaminated scrap metal and rubble

Description: Management options for the Department of Energy's increasing amounts of contaminated scrap metal and rubble include reuse as is, disposal, and recycling. Recycling, with its promise of resource recovery, virgin materials conservation, and land disposal minimization, emerges as a preferred management technique. Implementing a cost effective recycling program requires resolution of several issues including: establishing release limits for contaminants, controlling use of recycled materials creati… more
Date: January 1, 1992
Creator: Kluk, A.F. (USDOE, Washington, DC (United States)) & Hocking, E.K. (Argonne National Lab., Washington, DC (United States))
Partner: UNT Libraries Government Documents Department
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Measurement of radiofrequency fields

Description: We are literally surrounded by radiofrequency (RFR) and microwave radiation, from both natural and man-made sources. The identification and control of man-made sources of RFR has become a high priority of radiation safety professionals in recent years. For the purposes of this paper, we will consider RFR to cover the frequencies from 3 kHz to 300 MHz, and microwaves from 300 MHz to 300 GHz, and will use the term RFR interchangeably to describe both. Electromagnetic radiation and field below 3 k… more
Date: May 1, 1992
Creator: Leonowich, J.A.
Partner: UNT Libraries Government Documents Department
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Mode methods for strain-hardening structures

Description: An approximation method is being developed to predict the dynamic plastic response of rigid, strain-hardening structures. This method is analogous to the instantaneous mode techniques used to treat rigid, perfectly plastic structures in that a deflection shape involving a number of arbitrary functions of time is selected, based on static deformation profiles. Two stress fields are associated with the deflection shape: One satisfies the equations of motion with appropriate boundary and continuit… more
Date: April 1, 1992
Creator: Youngdahl, C.K.
Partner: UNT Libraries Government Documents Department
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Recent advances in high-temperature superconductor wire fabrication and applications development

Description: In this paper, recent advances in fabrication of HTS wires are summarized, and detailed discussion is provided for developments in near- and intermediate-term applications. Near-term applications, using presently obtainable current densities, include: liquid-nitrogen depth sensors, cryostat current leads, and magnetic bearings. Intermediate-term applications, using current densities expected to be available in the near future include fault-current limiters and short transmission lines. 25 refs.
Date: January 1, 1992
Creator: Hull, J.R. & Uherka, K.L.
Partner: UNT Libraries Government Documents Department
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Balance in machine architecture: Bandwidth on board and offboard, integer/control speed and flops versus memory

Description: The issues to be addressed here are those of balance'' in machine architecture. By this, we mean how much emphasis must be placed on various aspects of the system to maximize its usefulness for physics. There are three components that contribute to the utility of a system: How the machine can be used, how big a problem can be attacked, and what the effective capabilities (power) of the hardware are like. The effective power issue is a matter of evaluating the impact of design decisions trading … more
Date: April 1, 1992
Creator: Fischler, M.
Partner: UNT Libraries Government Documents Department
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Condensing economizers: Thermal performance and particulate removal efficiencies

Description: Condensing economizers can be used to increase the thermal efficiency of boilers and furnaces. This project has involved a study of these specifically for application to coal-water mixture fuels although the results can be extended to other fuels. experimental studies to evaluate thermal performance and removal of particulates across indirect contract economizers have been performed. The test arrangement incorporates oil firing with the injection of flyash into the flue gas to simulate coal com… more
Date: February 1, 1992
Creator: Butcher, T.A.; Litzke, Wai Lin (Brookhaven National Lab., Upton, NY (United States)) & Park, N. (Stony Brook Scientific, Ltd., Morristown, PA (United States))
Partner: UNT Libraries Government Documents Department
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Startup test strategy for demonstrating the ability of DWPF to comply with the WAPS

Description: This document discusses Startup Test Program for the Defense Waste Processing Facility (DWPF) which has been formulated to demonstrate that the DWPF can be operated in a safe, environmentally responsible manner to produce a product that will meet the requirements of the Waste Acceptance Preliminary Specifications. Startup will be managed in four distinct phases: Integrated Water Runs, Cold Chemical Runs, Waste Qualification Runs, and Radioactive Operation. A variety of feeds will be used for Wa… more
Date: January 1, 1992
Creator: Sproull, J.F. & Marra, S.L.
Partner: UNT Libraries Government Documents Department
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Treatment of high-level wastes from the IFR fuel cycle

Description: The Integral Fast Reactor (IFR) is being developed as a future commercial power source that promises to have important advantages over present reactors, including improved resource conservation and waste management. The spent metal alloy fuels from an IFR will be processed in an electrochemical cell operating at 500{degree}C with a molten chloride salt electrolyte and cadmium metal anode. After the actinides have been recovered from several batches of core and blanket fuels, the salt cadmium in… more
Date: January 1, 1992
Creator: Johnson, T. R.; Lewis, M. A.; Newman, A. E. & Laidler, J. J.
Partner: UNT Libraries Government Documents Department
open access

Oracle and the end-user: Practical implementation of applications in a multi-user, multi-platform environment

Description: This presentation will describe methods used to develop a standard user-interface to ORACLE applications, to train users, and document these systems in a diverse multi-user, multi-platform environment. Implementation and documentation of applications and training of users can be difficult when the end-users have diverse levels of computer proficiency and work with a multiple array of hardware platforms. We will discuss common problems encountered in such an environment and the approaches used t… more
Date: January 1, 1992
Partner: UNT Libraries Government Documents Department
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Plasma-Induced Conversion of Surface-Adsorbed Hydrocarbons

Description: Experimental results are reported for an electrical device for direct conversion of methane into higher hydrocarbons. A microchannel plate is excited with electrons from a photoemissive source, and electron impact ionization of methane on the inner surfaces of the microchannels creates an ion feedback process. The resulting low-density plasma creates higher hydrocarbons when charged particles impact the surfaces at grazing incidence. The production Of C{sub 2} to C{sub 8}-containing gases was n… more
Date: January 1, 1992
Creator: Sackinger, W. M.
Partner: UNT Libraries Government Documents Department
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Optimal forced-air distribution in new housing

Description: This paper summarizes a system integration approach to residential heating, cooling, and ventilation, embodied in a tight building envelope with precooling and dehumidification of forced ventilation air, and with ducts in the conditioned space.
Date: May 1, 1992
Creator: Andrews, J. W.
Partner: UNT Libraries Government Documents Department
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