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Reservoir continuous process improvement six sigma methodology implementation

Description: The six sigma methodology adopted by AlliedSignal Inc. for implementing continuous improvement activity was applied to a new manufacturing assignment for Federal Manufacturing & Technologies (FM&T). The responsibility for reservoir development/production was transferred from Rocky Flats to FM&T. Pressure vessel fabrication was new to this facility. No fabrication history for this type of product existed in-house. Statistical tools such as process mapping, failure mode and effects analysis, and … more
Date: December 1, 1996
Creator: Wannamaker, A.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Dimensional reduction as a tool for mesh refinement and trackingsingularities of PDEs

Description: We present a collection of algorithms which utilizedimensional reduction to perform mesh refinement and study possiblysingular solutions of time-dependent partial differential equations. Thealgorithms are inspired by constructions used in statistical mechanics toevaluate the properties of a system near a critical point. The firstalgorithm allows the accurate determination of the time of occurrence ofa possible singularity. The second algorithm is an adaptive meshrefinement scheme which can be u… more
Date: June 10, 2007
Creator: Stinis, Panagiotis
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Stability of the face-centered-cubic phase of heavy rare gas solids

Description: Our recent perturbation theory is applied to show that heavy rare gases solidify into a face-centered-cubic phase over a large temperature range near the melting lines. We have investigated the static, harmonic, and anharmonic contributions to the excess Helmholtz free energy and the stability to the face-centered-cubic phase. The observed stability is due to thermal contributions in the Helmholtz free energy.
Date: July 1, 1993
Creator: Ree, F. H. & Choi, Yumi
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Tev-Scale Black Hole Lifetimes in Extra-Dimensional Lovelock Gravity

Description: We examine the mass loss rates and lifetimes of TeV-scale extra dimensional black holes (BH) in ADD-like models with Lovelock higher-curvature terms present in the action. In particular we focus on the predicted differences between the canonical and microcanonical ensemble statistical mechanics descriptions of the Hawking radiation that results in the decay of these BH. In even numbers of extra dimensions the employment of the microcanonical approach is shown to generally lead to a significant … more
Date: January 5, 2006
Creator: Rizzo, Thomas G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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New theories for smectic and nematic liquid crystalline polymers

Description: A summary of results from new statistical-physics theories for both backbone and side-chain liquid crystalline polymers (LCPs) and for mixtures with LCPs is presented. Thermodynamic and molecular ordering properties (including odd-even effects) have been calculated as a function of pressure, density, temperature, and molecule chemical structures (including degree of polymerization and the following properties of the chemical structures of the repeat units: lengths and shapes, intra-chain rotati… more
Date: January 1, 1987
Creator: Dowell, F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Classical fluids of negative heat capacity

Description: It is shown that new parameters X can be defined such that the heat capacity C{sub X} {equivalent to} T({partial derivative}S/{partial derivative}T)X is negative, even when the canonical ensemble (i.e. at fixed T = ({partial derivative}U/{partial derivative}S) and Y {ne} X) is stable. As examples we treat black body radiation and general gas systems with nonsingular {kappa}{sub T}. For the case of a simple ideal gas we even exhibit an apparatus which enforces a constraint X(p,V) = const. that m… more
Date: June 1, 1992
Creator: Landsberg, P. T. (Southampton Univ., (United Kingdom). Faculty of Mathematical Studies) & Woodard, R. P. (Florida Univ., Gainesville, FL (United States). Dept. of Physics)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Optimization of the gas turbine-modular helium reactor using statistical methods to maximize performance without compromising system design margins

Description: This paper describes a statistical approach for determining the impact of system performance and design uncertainties on power plant performance. The objectives of this design approach are to ensure that adequate margin is provided, that excess margin is minimized, and that full advantage can be taken of unconsumed margin. It is applicable to any thermal system in which these factors are important. The method is demonstrated using the Gas Turbine Modular Helium Reactor as an example. The quanti… more
Date: July 1, 1995
Creator: Lommers, L. J.; Parme, L. L. & Shenoy, A. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Equation of state of reacting strongly coupled plasmas

Description: A brief review is given of the quantum statistical theory of strongly coupled many component reacting plasmas. It is shown that three distinct renormalizations of the many component activity series are required to obtain an expansion, which can properly handle strongly coupled reacting plasmas, for all states of ionization when Z > 1. Compensation between bound and scattering state contributions to the partition function is shown to be an important consideration and leads automatically to a con… more
Date: September 26, 1977
Creator: Rogers, F. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The applicability of certain Monte Carlo methods to the analysis of interacting polymers

Description: The authors consider polymers, modeled as self-avoiding walks with interactions on a hexagonal lattice, and examine the applicability of certain Monte Carlo methods for estimating their mean properties at equilibrium. Specifically, the authors use the pivoting algorithm of Madras and Sokal and Metroplis rejection to locate the phase transition, which is known to occur at {beta}{sub crit} {approx} 0.99, and to recalculate the known value of the critical exponent {nu} {approx} 0.58 of the system … more
Date: May 1, 1998
Creator: Krapp, D.M. Jr.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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New theories for smectic and nematic liquid-crystal polymers: Backbone LCPs (liquid crystalline polymers) and their mixtures and side-chain LCPs

Description: A summary of predictions and explanations from statistical-physics theories for both backbone and side-chain liquid crystalline polymers (LCPs) and for mixtures with backbone LCPs are presented. Trends in the thermodynamic and molecular ordering properties have been calculated as a function of pressure, density, temperature, and molecule chemical structures (including degree of polymerization and the following properties of the chemical structures of the repeat units: lengths and shapes, intra-… more
Date: January 1, 1987
Creator: Dowell, F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Statistical mechanics of nonlinear coherent structures: Kinks in the {Phi}{sup 6} model

Description: We study the thermodynamics of kinks in the {Phi}{sup 6} model using a Langevin code implemented on a massively parallel computer. This code can be used to study first order dynamical phase transitions which exhibit multiple length and time scales. The classical statistical mechanics of a 1 + 1-dimensional field theory reduces to a time-independent quantum problem in one dimension via the transfer integral method. Exact solutions of the Schroedinger equation exist for the {Phi}{sup 6} potential… more
Date: December 31, 1994
Creator: Habib, S. & Saxena, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Study of frustrated systems via dissipative maps

Description: The authors briefly describe a method for finding complex metastables states for frustrated classical systems, using a dissipative dynamical map. They show by example that this technique can give states which are very competitive in energy with the ground state, and with other, simpler states which are found by exhaustive search. The problem the authors look at is a two-body interaction F representing the repulsion between uniform layers of flux lines in a layered superconductor.
Date: April 1, 1994
Creator: Canright, G. S. & Watson, G. I.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Maximum likelihood borehole corrections for dual-detector density logs

Description: This report discusses Dual-detector density logs which have been used in the petroleum industry for years. The tool was designed with a second detector to allow compensation for the effect of a layer of mudcake between the tool and the formation being measured. The compensation algorithm commonly used calculates the correction to apply to the density measured by the long-spaced detector as proportional to the difference in the densities measured by the two detectors. The coefficient of proporti… more
Date: October 1, 1993
Creator: Carlson, R. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Instrument uncertainty predictions

Description: The accuracy of measurements and correlations should normally be provided for most experimental activities. The uncertainty is a measure of the accuracy of a stated value or equation. The uncertainty term reflects a combination of instrument errors, modeling limitations, and phenomena understanding deficiencies. This report provides several methodologies to estimate an instrument`s uncertainty when used in experimental work. Methods are shown to predict both the pretest and post-test uncertaint… more
Date: July 1, 1991
Creator: Coutts, D. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Experiments on statistical mechanics using resonance ionization spectroscopy

Description: Five different fluctuation phenomena at the atomic and molecular levels have been studied by resonance ionization spectroscopy techniques with one-atom detection sensitivity. The Poisson distribution described the observed frequency distributions suggesting random behavior. In addition, a gedanken experiment suggested by Einstein and Furth on the diffusion of atoms was performed in order to test the equality between time and ensemble averages. The obtained results confirmed the ergodicity of th… more
Date: April 1, 1984
Creator: Iturbe, J.; Allman, S. L.; Hurst, G. S. & Payne, M. G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Nonlinear analysis of EEG for epileptic seizures

Description: We apply chaotic time series analysis (CTSA) to human electroencephalogram (EEG) data. Three epoches were examined: epileptic seizure, non-seizure, and transition from non-seizure to seizure. The CTSA tools were applied to four forms of these data: raw EEG data (e-data), artifact data (f-data) via application of a quadratic zero-phase filter of the raw data, artifact-filtered data (g- data) and that was the residual after subtracting f-data from e-data, and a low-pass-filtered version (h-data) … more
Date: April 1, 1995
Creator: Hively, L. M.; Clapp, N. E.; Daw, C. S.; Lawkins, W. F. & Eisenstadt, M. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Functional integral approach to classical statistical dynamics

Description: A functional integral method is developed for the statistical solution of nonlinear stochastic differential equations which arise in classical dynamics. The functional integral approach provides a very natural and elegant derivation of the statistical dynamical equations that have been derived using the operator formalism of Martin, Siggia, and Rose.
Date: April 1, 1980
Creator: Jensen, R.V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The behavior of matter under nonequilibrium conditions: Fundamental aspects and applications. Progress Report for period April 15, 1990 - April 14, 1991

Description: Our report contains a brief summary of what has been achieved over the period of the contract. We have studied the behavior of matter under equilibrium conditions on three levels: (1) on the microscopic level in the frame of classical mechanics or of quantum theory; (2) on the stochastic level, which includes fluctuations; and (3) on the phenomenological, macroscopic level described by nonlinear equations. We first report on the level (1), then report on the levels (2) and (3).
Date: December 1, 1990
Creator: Prigogine, I.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Minicourse in Lie perturbative methods

Description: A skeletal presentation is given of the mechanics of Lie perturbative methods. The discussion is intended to enable the reader to begin to use the methods himself. The technique is illustrated by a specific example, in which we derive the ponderomotive Hamiltonian for a particle moving in a curl-free electric field.
Date: November 1, 1978
Creator: Mynick, H.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Advanced in Macrostatistical Hydrodynamics

Description: An overview is presented of research that focuses on slow flows of suspensions in which colloidal and inertial effects are negligibly small (Macrostatistical Hydrodynamics). First, we describe nuclear magnetic resonance imaging experiments to quantitatively measure particle migration occurring in concentrated suspensions undergoing a flow with a nonuniform shear rate. These experiments address the issue of how the flow field affects the microstructure of suspensions. In order to understand the … more
Date: August 1, 1993
Creator: Graham, A. L.; Tetlow, N.; Abbott, J. R.; Mondy, L. S. & Brenner, H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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