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Mixed-Mode Shell-Model Theory For Nuclear Structure Studies, V. G. Gueorguiev, W. E. Ormand, C. W. Johnson, J. P. Draayer Jan 2002

Mixed-Mode Shell-Model Theory For Nuclear Structure Studies, V. G. Gueorguiev, W. E. Ormand, C. W. Johnson, J. P. Draayer

Faculty Publications

We introduce a shell-model theory that combines traditional spherical states, which yield a diagonal representation of the usual single-particle interaction, with collective configurations that track deformations, and test the validity of this mixed-mode, oblique-basis shell-model scheme on [Formula Presented] The correct binding energy (within 2% of the full-space result) as well as low-energy configurations that have greater than 90% overlap with full-space results are obtained in a space that spans less than 10% of the full space. The results suggest that a mixed-mode shell-model theory may be useful in situations where competing degrees of freedom dominate the dynamics and full-space …

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Numerical Methods For The Simulation Of Dynamical Mass Transfer In Binaries, Patrick M. Motl, Joel E. Tohline, Juhan Frank Jan 2002

Numerical Methods For The Simulation Of Dynamical Mass Transfer In Binaries, Patrick M. Motl, Joel E. Tohline, Juhan Frank

Faculty Publications

We describe computational tools that have been developed to simulate dynamical mass transfer in semidetached, polytropic binaries that are initially executing synchronous rotation upon circular orbits. Initial equilibrium models are generated with a self-consistent field algorithm; models are then evolved in time with a parallel, explicit, Eulerian hydrodynamics code with no assumptions made about the symmetry of the system. Poisson's equation is solved along with the equations of ideal fluid mechanics to allow us to treat the nonlinear tidal distortion of the components in a fully self-consistent manner. We present results from several standard numerical experiments that have been conducted …

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Hyperbolicity Of The Baumgarte-Shapiro-Shibata-Nakamura System Of Einstein Evolution Equations, Olivier Sarbach, Gioel Calabrese, Jorge Pullin, Manuel Tiglio Jan 2002

Hyperbolicity Of The Baumgarte-Shapiro-Shibata-Nakamura System Of Einstein Evolution Equations, Olivier Sarbach, Gioel Calabrese, Jorge Pullin, Manuel Tiglio

Faculty Publications

We discuss an equivalence between the Baumgarte-Shapiro-Shibata-Nakamura (BSSN) formulation of the Einstein evolution equations, a subfamily of the Kidder-Scheel-Teukolsky formulation, and other strongly or symmetric hyperbolic first order systems with fixed shift and densitized lapse. This allows us to show under which conditions the BSSN system is, in a sense to be discussed, hyperbolic. This desirable property may account in part for the empirically observed better behavior of the BSSN formulation in numerical evolutions involving black holes. © 2002 The American Physical Society.

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Stability Properties Of A Formulation Of Einstein's Equations, Gioel Calabrese, Jorge Pullin, Olivier Sarbach, Manuel Tiglio Jan 2002

Stability Properties Of A Formulation Of Einstein's Equations, Gioel Calabrese, Jorge Pullin, Olivier Sarbach, Manuel Tiglio

Faculty Publications

We study the stability properties of the Kidder-Scheel-Teukolsky (KST) many-parameter formulation of Einstein's equations for weak gravitational waves on flat space-time from a continuum and numerical point of view. At the continuum, performing a linearized analysis of the equations around flat space-time, it turns out that they have, essentially, no non-principal terms. As a consequence, in the weak field limit the stability properties of this formulation depend only on the level of hyperbolicity of the system. At the discrete level we present some simple one-dimensional simulations using the KST family. The goal is to analyze the type of instabilities that …

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Convergence And Stability In Numerical Relativity, Gioel Calabrese, Jorge Pullin, Olivier Sarbach, Manuel Tiglio Jan 2002

Convergence And Stability In Numerical Relativity, Gioel Calabrese, Jorge Pullin, Olivier Sarbach, Manuel Tiglio

Faculty Publications

It is often the case in numerical relativity that schemes that are known to be convergent for well posed systems are used in evolutions of weakly hyperbolic formulations of Einstein's equations. Here we explicitly show that with several of the discretizations that have been used throughout the years, this procedure leads to nonconvergent schemes. That is, arbitrarily small initial errors are amplified without bound when resolution is increased, independently of the amount of numerical dissipation introduced. The lack of convergence introduced by this instability can be particularly subtle, in the sense that it can be missed by several convergence tests, …

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Perturbative Evolution Of Conformally Flat Initial Data For A Single Boosted Black Hole, Reinaldo J. Gleiser, Gaurav Khanna, Jorge Pullin Jan 2002

Perturbative Evolution Of Conformally Flat Initial Data For A Single Boosted Black Hole, Reinaldo J. Gleiser, Gaurav Khanna, Jorge Pullin

Faculty Publications

The conformally flat families of initial data typically used in numerical relativity to represent boosted black holes are not those of a boosted slice of Schwarzschild spacetime. If such data are used for each black hole in a collision, the emitted radiation will be partially due to the "relaxation" of the individual holes to "boosted Schwarzschild" form. We attempt to compute this radiation by treating the geometry for a single boosted conformally flat hole as a perturbation of a Schwarzschild black hole, which requires the use of second order perturbation theory. In this we attempt to mimic a previous calculation …

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Finite Spin-Foam-Based Theory Of Three- And Four-Dimensional Quantum Gravity, Rodolfo Gambini, Jorge Pullin Jan 2002

Finite Spin-Foam-Based Theory Of Three- And Four-Dimensional Quantum Gravity, Rodolfo Gambini, Jorge Pullin

Faculty Publications

Starting from Ooguri's construction for BF theory in three (and four) dimensions, we show how to construct a well defined theory with an infinite number of degrees of freedom. The spin network states that are kept invariant by the evolution operators of the theory are exact solutions of the Hamiltonian constraint of quantum gravity proposed by Thiemann. The resulting theory is the first example of a well defined, finite, consistent, spin-foam-based theory in a situation with an infinite number of degrees of freedom. Since it solves the quantum constraints of general relativity it is also a candidate for a theory …

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Close Limit Evolution Of Kerr-Schild Type Initial Data For Binary Black Holes, Olivier Sarbach, Manuel Tiglio, Jorge Pullin Jan 2002

Close Limit Evolution Of Kerr-Schild Type Initial Data For Binary Black Holes, Olivier Sarbach, Manuel Tiglio, Jorge Pullin

Faculty Publications

We eyolve the binary black hole initial data family proposed by Bishop et al. in the limit in which the black holes are close to each other. We present an exact solution of the linearized initial value problem based on their proposal and make use of a recently introduced generalized formalism for studying perturbations of Schwarzschild black holes in arbitrary coordinates to perform the evolution. We clarify the meaning of the free parameters of the initial data family through the results for the radiated energy and waveforms from the black hole collision. © 2002 The American Physical Society.

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Using Simple Marginal Analysis And Density Management Diagrams For Prescribing Density Management, Thomas J. Dean, S. Joseph Chang Jan 2002

Using Simple Marginal Analysis And Density Management Diagrams For Prescribing Density Management, Thomas J. Dean, S. Joseph Chang

Faculty Publications

This article presents a procedure to produce management regimes that not only maximize land value but also reflect stand development with simple marginal analyses of the accumulation and control of growing stock. An upper limit of growing stock is determined by translating management objectives into a future desired structure, and with this value as a guide for thinning age, marginal analysis is used to determine the planting density and the residual basal area after thinning. The procedure is demonstrated for a hypothetical loblolly pine plantation growing on land with a site index of 65 ft at 25 yr. The effects …

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Raising Livestock In Resource-Poor Communities Of The North West Province Of South Africa - A Participatory Rural Appraisal Study, J. K. Getchell, A. F. Vatta, P. W. Motswatswe, R. C. Krecek, R. Moerane, A. N. Pell, T. W. Tucker, S. Leshomo Jan 2002

Raising Livestock In Resource-Poor Communities Of The North West Province Of South Africa - A Participatory Rural Appraisal Study, J. K. Getchell, A. F. Vatta, P. W. Motswatswe, R. C. Krecek, R. Moerane, A. N. Pell, T. W. Tucker, S. Leshomo

Faculty Publications

A participatory research model was used in six village communities in the Central Region of the North West Province of South Africa in order to achieve the following broad objectives: to obtain information on the challenges owners face in raising livestock in these areas and to evaluate the livestock owners' level of knowledge of internal parasites in their animals. Information obtained at participatory workshops clearly indicated a need for improvements in water supply, schools, job creation, and health services. Lack of pasture for grazing livestock was also cited as being important. Other most frequently mentioned livestock problems included 'gall sickness' …

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Haemonchus Spp. In Sheep Farmed Under Resource-Poor Conditions In South-Africa - Effect On Haematocrit, Conjunctival Mucous Membrane Colour And Body Condition, A. F. Vatta, R. C. Krecek, M. J. Van Der Linde, P. W. Motswatswe, R. J. Grimbeek, E. F. Van Wijk, J. W. Hansen Jan 2002

Haemonchus Spp. In Sheep Farmed Under Resource-Poor Conditions In South-Africa - Effect On Haematocrit, Conjunctival Mucous Membrane Colour And Body Condition, A. F. Vatta, R. C. Krecek, M. J. Van Der Linde, P. W. Motswatswe, R. J. Grimbeek, E. F. Van Wijk, J. W. Hansen

Faculty Publications

A longitudinal study was conducted on the differential faecal egg counts, haematocrits and body condition scores of sheep belonging to resource-poor farmers at Rust de Winter, Gauteng province, and Kraaipan, North West Province, South Africa. The animals were scored for level of anaemia using the FAMACHA© method, an assay for the clinical evaluation of anaemia caused by Haemonchus spp. Periods of higher Haemonchus egg counts occurred from October to March for sheep at Rust de Winter and from September/October to February or April for sheep at Kraaipan. Lower haematocrit values were registered during these periods as was a higher incidence …

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Preference Of Food Particle Size Among Several Urban Ant Species., Linda M. Hooper-Bùi, Arthur G. Appel, Michael K. Rust Jan 2002

Preference Of Food Particle Size Among Several Urban Ant Species., Linda M. Hooper-Bùi, Arthur G. Appel, Michael K. Rust

Faculty Publications

Appropriate particle size may be a critical characteristic for effective granular ant baits. We examined the particle size preference of six species of pest ants to an anchovy-based bait. We also examined head capsule widths of Argentine ants, Linepithema humile (Mayr) (mean = 0.54 mm), California harvester ants, Pogonomyrmex californicus (Buckley) (mean = 1.63 mm), red imported fire ants, Solenopsis invicta Buren (mean = 0.9 mm), and southern fire ants, Solenopsis xyloni McCook (mean = 0.76 mm) and compared them with the first and second most preferred particle size. There were differences between particle size of which the most mass …

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Please Forgive Me: Transgressors’ Emotions And Physiology During Imagery Of Seeking Forgiveness And Victim Responses, Charlotte Vanoyen-Witvliet, Thomas Ludwig, David J. Bauer Jan 2002

Please Forgive Me: Transgressors’ Emotions And Physiology During Imagery Of Seeking Forgiveness And Victim Responses, Charlotte Vanoyen-Witvliet, Thomas Ludwig, David J. Bauer

Faculty Publications

We assessed transgressors’ subjective emotions and physiological responses in a within-subjects imagery study involving 20 male and 20 female participants. Two imagery conditions focused on the transgressor’s actions: participants 1) ruminated about a real-life transgression and 2) imagined seeking forgiveness from the victim. Three imagery conditions focused on the victim’s possible responses: participants imagined their victims responding with 1) a grudge, 2) genuine forgiveness, and 3) reconciliation. Compared to ruminations about one’s transgression or an unforgiving response from the victim, imagery of forgiveness-seeking and merciful responses from victims (forgiveness and reconciliation) prompted improvements in basic emotions (e.g., sadness, anger) and …

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Supreme Court Selection As War, Michael J. Gerhardt Jan 2002

Supreme Court Selection As War, Michael J. Gerhardt

Faculty Publications

No abstract provided.

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Memorial Tribute To Dr. C. Warren Irvin, Patrick Scott Jan 2002

Memorial Tribute To Dr. C. Warren Irvin, Patrick Scott

Faculty Publications

A tribute at a memorial gathering in Rutledge Chapel to Dr. C. Warren Irvin, MD (1921-2002), cardiologist, of Columbia, SC, a notable collector of Charles Darwin's books, for whom (with his wife Josie) the University of South Carolina's Rare Book & Special Collections Department is named.

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Effect Of Residual Thermal Stresses On Fracture Behavior And Mechanical Properties Of Al Sub 2 O Sub 3/Ni Cermets, Guo Jin Li, Da Ming Chen, Xiao Xian Huang, Jing Kun Guo Jan 2002

Effect Of Residual Thermal Stresses On Fracture Behavior And Mechanical Properties Of Al Sub 2 O Sub 3/Ni Cermets, Guo Jin Li, Da Ming Chen, Xiao Xian Huang, Jing Kun Guo

Faculty Publications

Effect of residual thermal stresses on fracture behavior and mechanical properties of Al2O3/Ni cermets was qualitatively explained by using theory on residual thermal stresses. When Ni particles are located within Al2O3 grains or Ni content is relatively low, tensile stresses are exerted at Al2O3-Al2O3 grain boundary. While fracturing, intergranular fracture is easily produced. When Ni particles are dispersed at Al2O3 grain boundary or Ni content is relatively high, compressive stresses are exerted at Al2O3-Al2O3grain boundary. …

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Environmental Regulation, Tort Law And Environmental Justice: What Could Have Been, Tseming Yang Jan 2002

Environmental Regulation, Tort Law And Environmental Justice: What Could Have Been, Tseming Yang

Faculty Publications

No abstract provided.

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Expectations For The Twenty-First Century: An Overview Of The New Limited Partnership Act, Thomas Geu, Barry Nekritz Jan 2002

Expectations For The Twenty-First Century: An Overview Of The New Limited Partnership Act, Thomas Geu, Barry Nekritz

Faculty Publications

No abstract provided.

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New Dimensions Of The Section 5 Enforcement Power, David Day Jan 2002

New Dimensions Of The Section 5 Enforcement Power, David Day

Faculty Publications

No abstract provided.

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The Advisory Practice And Procedure Of The Inter-American Court Of Human Rights:Contributing To The Evolution Of International Human Rights Law, Jo Pasqualucci Jan 2002

The Advisory Practice And Procedure Of The Inter-American Court Of Human Rights:Contributing To The Evolution Of International Human Rights Law, Jo Pasqualucci

Faculty Publications

No abstract provided.

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Deadliest Enemies: Law And The Making Of Race Relations On And Off Rosebud Reservation By Thomas Biolsi (Book Review), Frank Pommersheim Jan 2002

Deadliest Enemies: Law And The Making Of Race Relations On And Off Rosebud Reservation By Thomas Biolsi (Book Review), Frank Pommersheim

Faculty Publications

No abstract provided.

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Tell Me What You Want, What You Really, Really Want: Student Preferences About Literacy And Learning, Mary E. Styslinger Jan 2002

Tell Me What You Want, What You Really, Really Want: Student Preferences About Literacy And Learning, Mary E. Styslinger

Faculty Publications

No abstract provided.

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A Methodology Towards Measuring The Strategic Profile Of First-Mover Firms In Industrial Markets, Larry P. Pleshko, Richard A. Heiens, Leanne C. Mcgrath Jan 2002

A Methodology Towards Measuring The Strategic Profile Of First-Mover Firms In Industrial Markets, Larry P. Pleshko, Richard A. Heiens, Leanne C. Mcgrath

Faculty Publications

This study goes beyond most previous research on first-mover advantages by examining the broader concept of strategic marketing initiative. Specifically, a measurement scale was developed to assess the full extent of a firm's first-mover efforts. A total of 1200 firms were surveyed, with a response rate of 12.2%. The Strategic Marketing Initiative Scale developed exhibited high reliability, and has application in assisting management in recognizing marketing areas for first mover advantages. This can result in better timing of decisions about the strategy of when to act, contributing to the ability to create a competitive advantage around marketing initiatives.

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Compelled Expression And The Public Forum Doctrine, Howard M. Wasserman Jan 2002

Compelled Expression And The Public Forum Doctrine, Howard M. Wasserman

Faculty Publications

This Article analyzes the theory underlying the Fist Amendment protection against being compelled by government to utter, present, or fund unwanted expression. The author creates a three-part model for determining when the fire speech rights of an objecting payer have been triggered. Under that model, First Amendment rights are implicated when there has been an actual government compulsion requiring an individual to give money to, or for the express benefit of, a specific private speaker for some use that, in itself, should be understood as expressive. This model strikes a necessary balance between the important theoretical underpinnings of the protection …

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Fa Composition Of Crude Oil Recovered From Catfish Viscera, Subramaniam Sathivel, Witoon Prinyawiwatkul, Casey C. Grimm, Joan M. King, Steven Lloyd Jan 2002

Fa Composition Of Crude Oil Recovered From Catfish Viscera, Subramaniam Sathivel, Witoon Prinyawiwatkul, Casey C. Grimm, Joan M. King, Steven Lloyd

Faculty Publications

The FA composition of crude catfish oil recovered from whole viscera, digestive tract, liver, gallbladder, and visceral storage fat was determined and compared with that of fillet and nugget (abdominal portion). About 34% crude fat (wet basis) could be recovered from the whole catfish viscera. FA found in crude catfish visceral oil were C14:0, C16:0, C16:1, C18:0, C18:1, C18:2, C18:3, C20:0, C20:1, C20:2, C20:3, C20:4, and C22:6, the predominant FA being C18:1, C16:0, C18:2, and C18:0. Catfish visceral oil was characterized by a high level of unsaturated FA, which was similarly found in fillet and nugget. Total unsaturated FA in …

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Semiparametric Maximum Likelihood Estimates Of Spatial Dependence, R. Kelley Pace, James P. Lesage Jan 2002

Semiparametric Maximum Likelihood Estimates Of Spatial Dependence, R. Kelley Pace, James P. Lesage

Faculty Publications

We semiparametrically model spatial dependence via a combination of simpler weight matrices (termed spatial basis matrices) and fit this model via maximum likelihood. Estimation of the model relies on the intuition that bounds to the log-determinant term in the log-likelihood can provide penalties to overfitting both the level and pattern of spatial dependence. By relying on symmetric and doubly stochastic spatial basis matrices that reflect different weight specifications assigned to neighboring observations, we are able to derive a mathematical expression for bounds on the log-determinant term that appears in the likelihood function. These bounds can be conveniently calculated allowing us …

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Crustal Fissuring On The Crest Of The Southern East Pacific Rise At 17˚15'-40'S, Dawn J. Wright, Rachel M. Haymon, Scott M. White, Ken C. Macdonald Jan 2002

Crustal Fissuring On The Crest Of The Southern East Pacific Rise At 17˚15'-40'S, Dawn J. Wright, Rachel M. Haymon, Scott M. White, Ken C. Macdonald

Faculty Publications

Fissure densities and widths have been mapped along the axial zone of the superfast spreading southern East Pacific Rise (EPR) at 17_150–400S with the near-bottom DSL-120 and Argo II imaging systems. We observe that the youngest lava flows (on a relative age scale) are sparsely fissured and that there is a cumulative increase in fissure abundance with time that produces a strong positive correlation between fissure density and relative age of lava flows. Average fissure widths were used to estimate fissure depths. In the 17_150–400S area, calculated fissure depths are estimated to extend below the seismic layer 2A/2B boundary, and …

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Love, Marriage, & ..., Trevor O'Reggio Jan 2002

Love, Marriage, & ..., Trevor O'Reggio

Faculty Publications

No abstract provided.

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The Algebra And Geometry Of Curve And Surface Inversion, Thomas W. Sederberg, Eng-Wee Chionh, Kent Ridge Jan 2002

The Algebra And Geometry Of Curve And Surface Inversion, Thomas W. Sederberg, Eng-Wee Chionh, Kent Ridge

Faculty Publications

An inversion equation takes the Cartesian coordinates of a point on a parametric curve or surface and returns the parameter value(s) of that point. A 2-D curve inversion equation has the form t = f(x,y)/g(x,y). This paper shows that practical insight into inversion can be obtained by studying the geometry of the implicit curves f(x,y) = 0 and g(x,y) = 0. For example, the relationship between the singular locus of the parametric curve and the lowest possible degree of an inversion equation can be understood in this way. Also, insight is given into what parameter value will be returned if …

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Pair Attribute Learning: Network Construction Using Pair Features, Tony R. Martinez, Eric K. Henderson Jan 2002

Pair Attribute Learning: Network Construction Using Pair Features, Tony R. Martinez, Eric K. Henderson

Faculty Publications

We present the Pair Attribute Learning (PAL) algorithm for the selection of relevant inputs and network topology. Correlations on training instance pairs are used to drive network construction of a single-hidden layer MLP. Results on nine learning problems demonstrate 70% less complexity, on average, without a significant loss of accuracy.

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