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Regularization and renormalization of quantum field theory in curved space-time. [Pauli-Villars regulator fields]

Description: It is proposed that field theories quantized in a curved space-time manifold can be conveniently regularized and renormalized with the aid of Pauli-Villars regulator fields. The method avoids the conceptual difficulties of covariant point-separation approaches, by starting always from a manifestly generally covariant action, and the technical limitations of the dimensional reqularization approach, which requires solution of the theory in arbitrary dimension in order to go beyond a weak-field expansion. An action is constructed which renormalizes the weak-field perturbation theory of a massive scalar field in two space-time dimensions--it is shown that the trace anomaly previously found in dimensional regularization and some point-separation calculations also arises in perturbation theory when the theory is Pauli-Villars regulated. One then studies a specific solvable two-dimensional model of a massive scalar field in a Robertson-Walker asymptotically flat universe. It is shown that the action previously considered leads, in this model, to a well defined finite expectation value for the stress-energy tensor. The particle production (less than 0 in/vertical bar/theta/sup mu nu/(x,t)/vertical bar/0 in greater than for t ..-->.. + infinity) is computed explicitly. Finally, the validity of weak-field perturbation theory (in the appropriate range of parameters) is checked directly in the solvable model, and the trace anomaly computed in the asymptotic regions t..-->.. +- infinity independently of any weak field approximation. The extension of the model to higher dimensions and the renormalization of interacting (scalar) field theories are briefly discussed.
Date: January 1, 1977
Creator: Bernard, C. & Duncan, A.
Partner: UNT Libraries Government Documents Department

Power System Extreme Event Detection: The VulnerabilityFrontier

Description: In this work we apply graph theoretic tools to provide aclose bound on a frontier relating the number of line outages in a gridto the power disrupted by the outages. This frontier describes theboundary of a space relating the possible severity of a disturbance interms of power disruption, from zero to some maximum on the boundary, tothe number line outages involved in the event. We present the usefulnessof this analysis with a complete analysis of a 30 bus system, and presentresults for larger systems.
Date: October 17, 2007
Creator: Lesieutre, Bernard C.; Pinar, Ali & Roy, Sandip
Partner: UNT Libraries Government Documents Department

Preliminary heavy-light decay constants from the MILC Collaboration

Description: Preliminary results from the MILC Collaboration for f{sub B}, f{sub B{sub s}}, f{sub D}, f{sub D{sub s}} and their ratios are presented. We compute in the quenched approximation at {beta} = 6.3, 6.0 and 5.7 with Wilson light quarks and static and Wilson heavy quarks. We attempt to quantify all systematic errors other than quenching.
Date: December 1, 1994
Creator: Bernard, C.
Partner: UNT Libraries Government Documents Department

Conveyance Characteristics of the Nueces River, Cotulla to Simmons, Texas

Description: From purpose and scope: The purpose of this study is to provide data and hydrologic interpretations for use by the Bureau of Reclamation in evaluating and quantifying natural water losses that are known to occur along some reaches of the Nueces River. Specifically, this report presents data and analyses describing the conveyance characteristics of that reach of the Nueces River from Cotulla to Simmons.
Date: 1983
Creator: Massey, Bernard C. & Reeves, William E.
Partner: UNT Libraries Government Documents Department

Introduction to lattice gaugefixing and effective quark and gluon masses

Description: We report on the status of quark and gluon propagators in quenched, gaugefixed lattice QCD. In Landau gauge we find that the effective quark mass in the chiral limit is M{sub q} {approximately} 350(40)MeV. Quark and gluon propagators, the slope of the quark dispersion relation, and effective masses all appear to depend on gauge. A link-chain picture of lattice gaugefixing in the color N {yields} {infinity} and strong coupling limit, where the system becomes almost solvable, supports the gauge variance of these numerical results.
Date: October 1, 1992
Creator: Bernard, C.; Soni, A. & Yee, K.
Partner: UNT Libraries Government Documents Department

The gluon propagator in momentum space

Description: We consider quenched QCD on a 16{sup 3}{times}40 lattice at {beta}=6.0. We give preliminary numerical results for the lattice gluon propagator evaluated both in coordinate and momentum space. Our findings are compared with earlier results in the literature at zero momentum. In addition, by considering nonzero momenta we attempt to extract the form of the propagator and compare it to continuum predictions formulated by Gribov and others.
Date: December 31, 1992
Creator: Bernard, C.; Parrinello, C. & Soni, A.
Partner: UNT Libraries Government Documents Department

Results for f{sub B} and f{sub D} at {beta} = 6.3

Description: We have computed the decay constants for the B and D mesons, using quenched lattices at {beta} = 6.3, by interpolating between the static approximation of Eichten and the conventional (``heavy`` Wilson fermion) method. A more careful treatment of the static result using better sources with longer time-displacements and a modification to the Wilson quark normalization to correct approximately for lattice effects in the large-am regime have led to the elimination of the large discrepancy between the two methods which had been previously observed. We report final results, with estimates of various systematic errors.
Date: December 31, 1992
Creator: Bernard, C.; Labrenz, J. & Soni, A.
Partner: UNT Libraries Government Documents Department

Update on B{sub K} with Wilson fermions

Description: The K-{anti K} mixing matrix element is a hadronic matrix element that is of crucial importance to electroweak phenomenology. For convenience, the authors introduce the so called bag parameter, B{sub K}. It has been known for a long time that B{sub K} is amenable to lattice Monte-Carlo methods. Indeed, recently Sharpe and collaborators, using staggered formulation for fermions have made remarkable progress in calculating B{sub K} and have reported a result with an impressive accuracy. In this work the authors will present their results for B{sub K} using the Wilson formulation for fermions.
Date: December 1, 1994
Creator: Bernard, C. & Soni, A.
Partner: UNT Libraries Government Documents Department

A review of market monitoring activities at U.S. independent system operators

Description: Policymakers have increasingly recognized the structural impediments to effective competition in electricity markets, which has resulted in a renewed emphasis on the need for careful market design and market monitoring in wholesale and retail electricity markets. In this study, we review the market monitoring activities of four Independent System Operators in the United States, focusing on such topics as the organization of an independent market monitoring unit (MMU), the role and value of external market monitors, performance metrics and indices to aid in market analysis, issues associated with access to confidential market data, and market mitigation and investigation authority. There is consensus across the four ISOs that market monitoring must be organizationally independent from market participants and that ISOs should have authority to apply some degree of corrective actions on the market, though scope and implementation differ across the ISOs. Likewise, current practices regarding access to confidential market data by state energy regulators varies somewhat by ISO. Drawing on our interviews and research, we present five examples that illustrate the impact and potential contribution of ISO market monitoring activities to enhance functioning of wholesale electricity markets. We also discuss several key policy and implementation issues that Western state policymakers and regulators should consider as market monitoring activities evolve in the West.
Date: January 1, 2004
Creator: Lesieutre, Bernard C.; Goldman, Charles & Bartholomew, Emily
Partner: UNT Libraries Government Documents Department

Electricity transmission congestion costs: A review of recent reports

Description: Recently, independent system operators (ISOs) and others have published reports on the costs of transmission congestion. The magnitude of congestion costs cited in these reports has contributed to the national discussion on the current state of U.S. electricity transmission system and whether it provides an adequate platform for competition in wholesale electricity markets. This report reviews reports of congestion costs and begins to assess their implications for the current national discussion on the importance of the U.S. electricity transmission system for enabling competitive wholesale electricity markets. As a guiding principle, we posit that a more robust electricity system could reduce congestion costs; and thereby, (1) facilitate more vibrant and fair competition in wholesale electricity markets, and (2) enable consumers to seek out the lowest prices for electricity. Yet, examining the details suggests that, sometimes, there will be trade-offs between these goals. Therefore, it is essential to understand who pays, how much, and how do they benefit in evaluating options (both transmission and non-transmission alternatives) to address transmission congestion. To describe the differences among published estimates of congestion costs, we develop and motivate three ways by which transmission congestion costs are calculated in restructured markets. The assessment demonstrates that published transmission congestion costs are not directly comparable because they have been developed to serve different purposes. More importantly, critical information needed to make them more comparable, for example in order to evaluate the impacts of options to relieve congestion, is sometimes not available.
Date: October 1, 2003
Creator: Lesieutre, Bernard C. & Eto, Joseph H.
Partner: UNT Libraries Government Documents Department

Use of the STORM Model for Estimating the Quantity and Quality of Runoff from the Metropolitan Area of Houston, Texas

Description: From introduction: The purpose of this study, made in cooperation with the Texas Department of Water Resources, was to adapt an existing model to utilize available streamflow and water quality data to compute runoff from the Houston area and to compute the concentrations and loads of selected water-quality constituents contained in the inflow to Galveston Bay.
Date: November 1979
Creator: Waddell, Kidd M.; Massey, Bernard C. & Jennings, Marshall E.
Partner: UNT Libraries Government Documents Department

A Review of Recent RTO Benefit-Cost Studies: Toward MoreComprehensive Assessments of FERC Electricity RestructuringPolicies

Description: During the past three years, government and private organizations have issued more than a dozen studies of the benefits and costs of Regional Transmission Organizations (RTOs). Most of these studies have focused on benefits that can be readily estimated using traditional production-cost simulation techniques, which compare the cost of centralized dispatch under an RTO to dispatch in the absence of an RTO, and on costs associated with RTO start-up and operation. Taken as a whole, it is difficult to draw definitive conclusions from these studies because they have not examined potentially much larger benefits (and costs) resulting from the impacts of RTOs on reliability management, generation and transmission investment and operation, and wholesale electricity market operation. This report: (1) Describes the history of benefit-cost analysis of FERC electricity restructuring policies; (2)Reviews current practice by analyzing 11 RTO benefit-cost studies that were published between 2002 and 2004 and makes recommendations to improve the documentation of data and methods and the presentation of findings in future studies that focus primarily on estimating short-run economic impacts; and (3) Reviews important impacts of FERC policies that have been overlooked or incompletely treated by recent RTO benefit-cost studies and the challenges to crafting more comprehensive assessments of these impacts based on actual performance, including impacts on reliability management, generation and transmission investment and operation, and wholesale electricity market operation.
Date: December 1, 2005
Creator: Eto, Joseph H. & Lesieutre, Bernard C.
Partner: UNT Libraries Government Documents Department

Flavor changing neutral current transitions on the lattice for heavy-light systems

Description: Flavor changing neutral current transitions are a very important test of the standard model. Some of the channels can also be very useful for extracting the Kobayashi-Maskawa mixing matrix elements. However, their potential applications are limited by the uncertainties in the relevant hadronic matrix elements. We show that these matrix elements are also amenable to lattice techniques. In this study, we focus on radiative transitions such as B {yields} K*{gamma} and present preliminary results obtained by using 24{sup 3} {times} 40 lattices at {Beta} = 6.0.
Date: January 1, 1992
Creator: Bernard, C. W.; Hsieh, P. F. & Soni, A.
Partner: UNT Libraries Government Documents Department

Calculating the Isgur-Wise function on the lattice

Description: We calculate the Isgur-Wise function by measuring the heavy-heavy meson transition matrix element on the lattice. The standard Wilson action is used for both the heavy and light quarks. Our first numerical results are presented.
Date: December 31, 1992
Creator: Bernard, C. W.; Shen, Y. & Soni, A.
Partner: UNT Libraries Government Documents Department

Decay constants of heavy-light pseudoscalars: Results at {beta} = 6.3

Description: A lattice calculation of the pseudoscalar decay constant for heavy-light mesons is reported. Emphasis is placed on preliminary results obtained using wall-source propagators at {beta} = 6.3. The previously-observed discrepancy between the static and conventional approaches appears to be much reduced.
Date: January 1, 1992
Creator: Bernard, C.; Heard, C. M.; Labrenz, J. & Soni, A.
Partner: UNT Libraries Government Documents Department

Power system extreme event screening using graphpartitioning

Description: We propose a partitioning problem in a power system contextthat weighs the two objectives of minimizing cuts between partitions andmaximizing the power imbalance between partitions. We then pose theproblem in a purely graph theoretic sense. We offer an approximatesolution through relaxation of the integer problem and suggest refinementusing stochastic methods. Results are presented for the IEEE 30-bus and118-bus electric power systems.
Date: September 6, 2006
Creator: Lesieutre, Bernard C.; Roy, Sandip; Donde, Vaibhav & Pinar, Ali
Partner: UNT Libraries Government Documents Department

The potential impacts of a competitive wholesale market in the midwest: A preliminary examination of centralized dispatch

Description: In March 2005, the Midwest Independent System Operator (MISO) will begin operating the first-ever wholesale market for electricity in the central and upper Midwestern portion of the United States. Region-wide, centralized, security-constrained, bid-based dispatch will replace the current system of decentralized dispatch by individual utilities and control areas. This report focuses on how the operation of generators may change under centralized dispatch. We analyze a stylized example of these changes by comparing a base case dispatch based on a ''snapshot'' taken from MISO's state estimator for an actual, historical dispatch (4 p.m., July 7, 2003) to a hypothetical, centralized dispatch that seeks to minimize the total system cost of production, using estimated cost data collected by the EIA. Based on these changes in dispatch, we calculate locational marginal prices, which in turn reveals the location of congestion within MISO's footprint, as well as the distribution of congestion revenues. We also consider two sensitivity scenarios that examine (1) the effect of changes in MISO membership (2003 vs. 2004 membership lists), and (2) different load and electrical data, based on a snapshot from a different date and time (1 p.m., Feb. 18, 2004). Although our analysis offers important insights into how the MISO market could operate when it opens, we do not address the question of the total benefits or costs of creating a wholesale market in the Midwest.
Date: July 1, 2004
Creator: Lesieutre, Bernard C.; Bartholomew, Emily; Eto, Joseph H.; Hale, Douglas & Luong, Thanh
Partner: UNT Libraries Government Documents Department

Lattice study of D yields K. pi

Description: Exclusive two body nonleptonic weak decay matrix elements are studied for D mesons using lattice techniques with Wilson fermions in the quenced approximation. 12 refs.
Date: January 1, 1989
Creator: Bernard, C. (California Univ., Santa Barbara, CA (USA). Inst. for Theoretical Physics); Simone, J. & Soni, A. (Brookhaven National Lab., Upton, NY (USA))
Partner: UNT Libraries Government Documents Department

Flavor changing neutral current transitions on the lattice for heavy-light systems

Description: Flavor changing neutral current transitions are a very important test of the standard model. Some of the channels can also be very useful for extracting the Kobayashi-Maskawa mixing matrix elements. However, their potential applications are limited by the uncertainties in the relevant hadronic matrix elements. We show that these matrix elements are also amenable to lattice techniques. In this study, we focus on radiative transitions such as B {yields} K*{gamma} and present preliminary results obtained by using 24{sup 3} {times} 40 lattices at {Beta} = 6.0.
Date: January 1, 1992
Creator: Bernard, C.W. (Washington Univ., St. Louis, MO (United States). Dept. of Physics); Hsieh, P.F. & Soni, A. (Brookhaven National Lab., Upton, NY (United States))
Partner: UNT Libraries Government Documents Department

Improving Dynamic Load and Generator Response PerformanceTools

Description: This report is a scoping study to examine research opportunities to improve the accuracy of the system dynamic load and generator models, data and performance assessment tools used by CAISO operations engineers and planning engineers, as well as those used by their counterparts at the California utilities, to establish safe operating margins. Model-based simulations are commonly used to assess the impact of credible contingencies in order to determine system operating limits (path ratings, etc.) to ensure compliance with NERC and WECC reliability requirements. Improved models and a better understanding of the impact of uncertainties in these models will increase the reliability of grid operations by allowing operators to more accurately study system voltage problems and the dynamic stability response of the system to disturbances.
Date: November 1, 2005
Creator: Lesieutre, Bernard C.
Partner: UNT Libraries Government Documents Department

Introduction to lattice gaugefixing and effective quark and gluon masses

Description: We report on the status of quark and gluon propagators in quenched, gaugefixed lattice QCD. In Landau gauge we find that the effective quark mass in the chiral limit is M[sub q] [approximately] 350(40)MeV. Quark and gluon propagators, the slope of the quark dispersion relation, and effective masses all appear to depend on gauge. A link-chain picture of lattice gaugefixing in the color N [yields] [infinity] and strong coupling limit, where the system becomes almost solvable, supports the gauge variance of these numerical results.
Date: January 1, 1992
Creator: Bernard, C. (Washington Univ., St. Louis, MO (United States). Dept. of Physics); Soni, A. & Yee, K. (Brookhaven National Lab., Upton, NY (United States))
Partner: UNT Libraries Government Documents Department

Weak matrix elements of kaons

Description: We present results from the Wilson fermion part of the Grand Challenge'' weak matrix element project. A new procedure for correcting the chiral behavior of {Beta}{sub LL}{sup sd}, the K{sup 0}-{bar K}{sup 0} {Beta} parameter,'' is proposed and applied. On our largest lattice (24{sup 3} {times} 40 at {beta} = 6.0), we get {Beta}{sub LL}{sup sd} = .86 {plus minus} .11 {plus minus} .05, where the first error is statistical and the second is a measure of the systematic errors due to the procedure and to related finite-size effects. Results for the direct K{sup +} {yields} {pi}{sup +}{pi}{sup 0} amplitude are also presented. There is some evidence for higher order chiral effects which may make these results compatible both with experiment and with the {Beta}{sub LL}{sup sd} computation. The status of the direct K{sub s}{sup 0} {yields} {pi} {sup +} {pi}{sup {minus}} {Delta}I = 1/2 amplitude is then discussed. 11 refs., 6 figs., 1 tab.
Date: January 1, 1989
Creator: Bernard, C. (California Univ., Santa Barbara, CA (USA). Inst. for Theoretical Physics) & Soni, A. (Brookhaven National Lab., Upton, NY (USA))
Partner: UNT Libraries Government Documents Department