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2004

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Full-Text Articles in Physical Sciences and Mathematics

Refuge Update – November/December 2004, Volume 1, Number 5 Nov 2004

Refuge Update – November/December 2004, Volume 1, Number 5

RefugeUpdate (USFWS-NWRS)

Table of Contents:

In the Eye of the Storm, page 3 Bon Secour Refuge biologist details a storm’s aftermath.

Looking Beyond the Ecology to the Human History, page 5 Archaeology students survey Fish Springs Refuge.

Focus on . . . Water and Its Impact on Refuges, pages 8-19 Water is essential for all ecological processes. Nowhere is that more evident than on national wildlife refuges.

Sharing an Appreciation for Nature, page 6 Those who are visually disabled can appreciate any refuge.

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The Nadca Probe, Issue 236 Nov 2004

The Nadca Probe, Issue 236

The Probe: Newsletter of the National Animal Damage Control Association


Observations of the "Rodentator" Device for Controlling Blackailed Prairie Dogs
Bruggers to Head NWRC
CALENDAR OF UPCOMING EVENTS
Are rodents immune from contracting rabies?
The ICWDM Continues to Evolve
Wyoming Presents Grizzly Bear Management Proposal
Vantassel Moves to the University of Nebraska

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Variable Bandwidth Filter For Multibeam Echo-Sounding Bottom Detection, Barbara J. Kraft, Christian De Moustier Nov 2004

Variable Bandwidth Filter For Multibeam Echo-Sounding Bottom Detection, Barbara J. Kraft, Christian De Moustier

Center for Coastal and Ocean Mapping

The accuracy of a seafloor map derived from multibeam swath bathymetry depends first and foremost on the quality of the bottom detection process that yields estimates of the arrival time and angle of bottom echoes received in each beam. Filtering of each beam with a fixed bandwidth filter, with the bandwidth based on the length of the transmitted pulse, reduces the error associated with the time-angle estimates. However, filters of this type can not be optimal over the wide range of operational environments encountered. Better results are obtained with a processing scheme that varies the filter bandwidth across the swath …

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Light Hadrons With Improved Staggered Quarks: Approaching The Continuum Limit, James E. Hetrick, C. Aubin Nov 2004

Light Hadrons With Improved Staggered Quarks: Approaching The Continuum Limit, James E. Hetrick, C. Aubin

All Faculty Articles - School of Engineering and Computer Science

We have extended our program of QCD simulations with an improved Kogut-Susskind quark action to a smaller lattice spacing, approximately 0.09 fm. Also, the simulations with a ≈ 0.12 fm have been extended to smaller quark masses. In this paper we describe the new simulations and computations of the static quark potential and light hadron spectrum. These results give information about the remaining dependences on the lattice spacing. We examine the dependence of computed quantities on the spatial size of the lattice, on the numerical precision in the computations, and on the step size used in the numerical integrations. We …

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Light Pseudoscalar Decay Constants, Quark Masses, And Low Energy Constants From Three Flavor Lattice Qcd, James E. Hetrick, C. Aubin Nov 2004

Light Pseudoscalar Decay Constants, Quark Masses, And Low Energy Constants From Three Flavor Lattice Qcd, James E. Hetrick, C. Aubin

All Faculty Articles - School of Engineering and Computer Science

As part of our program of lattice simulations of three-flavor QCD with improved staggered quarks, we have calculated pseudoscalar meson masses and decay constants for a range of valence quark masses and sea-quark masses on lattices with lattice spacings of about 0.125 and 0.09 fm. We fit the lattice data to forms computed with “staggered chiral perturbation theory.” Our results provide a sensitive test of the lattice simulations, and especially of the chiral behavior, including the effects of chiral logarithms. We find: fπ = 129.5 ± 0.9 ± 3.5 MeV, fK = 156.6 ± 1.0 ± 3.6 MeV, and fK/ …

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The Effect Of Low Energy Electron And Uv/Vis Radiation Aging On The Electron Emission Properties And Breakdown Of Thin-Film Dielectrics, John R. Dennison, C. D. Thomson, Alec Sim Nov 2004

The Effect Of Low Energy Electron And Uv/Vis Radiation Aging On The Electron Emission Properties And Breakdown Of Thin-Film Dielectrics, John R. Dennison, C. D. Thomson, Alec Sim

All Physics Faculty Publications

Studies of secondary and backscattered electron yield curves of thin-film dielectrics have recently been made using pulsed, low current electron beam methods to minimize insulator charging. These capabilities have allowed us to investigate the evolution of surface and internal charge profiles as a function of low energy electron (keV) pulsed-electron fluence to determine how quickly insulators charge, and how this can affect subsequent electron emission properties. We have also studied critical incident electron energies that result in electrical breakdown of insulator materials and the effect of breakdown on subsequent emission, charging and conduction. The qualitative physics of such processes in …

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The Shallow Water Equations In Lagrangian Coordinates, J. L. Mead Nov 2004

The Shallow Water Equations In Lagrangian Coordinates, J. L. Mead

Mathematics Faculty Publications and Presentations

Recent advances in the collection of Lagrangian data from the ocean and results about the well-posedness of the primitive equations have led to a renewed interest in solving flow equations in Lagrangian coordinates. We do not take the view that solving in Lagrangian coordinates equates to solving on a moving grid that can become twisted or distorted. Rather, the grid in Lagrangian coordinates represents the initial position of particles, and it does not change with time. However, using Lagrangian coordinates results in solving a highly nonlinear partial differential equation. The nonlinearity is mainly due to the Jacobian of the coordinate …

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Transitions Into The Negative-Energy Dirac Continuum, P Krekora, Q Su, Rainer Grobe Nov 2004

Transitions Into The Negative-Energy Dirac Continuum, P Krekora, Q Su, Rainer Grobe

Faculty publications – Physics

We compare the predictions of the single-particle Dirac equation with quantum field theory for an electron subjected to a space and time dependent field. We demonstrate analytically and numerically that a transition into the negative-energy subspace predicted by the single-particle Dirac equation is directly associated with the degree of suppression of pair-production as described by quantum field theory. We show that the portion of the mathematical wave function that populates the negative-energy states corresponds to the difference between the positron spatial density for systems with and without an electron initially present.

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Inside Unlv, Cate Weeks, Carol C. Harter, Holly Ivy De Vore, Gian Galassi, Diane Russell Nov 2004

Inside Unlv, Cate Weeks, Carol C. Harter, Holly Ivy De Vore, Gian Galassi, Diane Russell

Inside UNLV

No abstract provided.

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Elemental Principles Of T-Topos, Goro Kato Nov 2004

Elemental Principles Of T-Topos, Goro Kato

Mathematics

In this paper, a sheaf-theoretic approach toward fundamental problems in quantum physics is made. For example, the particle-wave duality depends upon whether or not a presheaf is evaluated at a specified object. The t-topos theoretic interpretations of double-slit interference, uncertainty principle(s), and the EPR-type non-locality are given. As will be explained, there are more than one type of uncertainty principle: the absolute uncertainty principle coming from the direct limit object corresponding to the refinements of coverings, the uncertainty coming from a micromorphism of shortest observable states, and the uncertainty of the observation image. A sheaf theoretic approach …

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Resonance-Enhanced Multiphoton Ionization For Real-Time Monitoring Of Trichloroethylene Formed By Degradation Of Tetrachloroethylene Using Zero-Valent Zinc, Kui Chen, Jack E. Pender, John L. Ferry, S. Michael Angel Nov 2004

Resonance-Enhanced Multiphoton Ionization For Real-Time Monitoring Of Trichloroethylene Formed By Degradation Of Tetrachloroethylene Using Zero-Valent Zinc, Kui Chen, Jack E. Pender, John L. Ferry, S. Michael Angel

Faculty Publications

Resonance-enhanced multiphoton ionization (REMPI) is investigated as a potential technique for real-time monitoring of selected volatile organochloride compounds (VOCs). In a proof-of-concept experiment, the progress of the reductive-degradation of tetrachloroethylene (PCE) to trichloroethylene (TCE) by zero-valent zinc was monitored by REMPI measurements performed in the headspace above the PCE solution. Two-photon resonant REMPI spectra of TCE and PCE were recorded over the wavelength range 305–320 nm. The concentrations of PCE and TCE in the headspace were monitored by measurement of the ionization signal with 315.64- and 310.48-nm excitation for PCE and TCE, respectively. Calibration curves yielded a linear range of …

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An Overview Of The Respondent-Generated Intervals (Rgi) Approach To Sample Surveys, S. James Press, Judith M. Tanur Nov 2004

An Overview Of The Respondent-Generated Intervals (Rgi) Approach To Sample Surveys, S. James Press, Judith M. Tanur

Journal of Modern Applied Statistical Methods

This article brings together many years of research on the Respondent-Generated Intervals (RGI) approach to recall in factual sample surveys. Additionally presented is new research on the use of RGI in opinion surveys and the use of RGI with gamma-distributed data. The research combines Bayesian hierarchical modeling with various cognitive aspects of sample surveys.

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Statistics And Technology: Reflections On 35 Years Of Change, James J. Higgins Nov 2004

Statistics And Technology: Reflections On 35 Years Of Change, James J. Higgins

Journal of Modern Applied Statistical Methods

From the days when statistical calculations were done on mechanical calculators to today, technology has transformed the discipline of statistics. More than just giving statisticians the power to crunch numbers, it has fundamentally changed the way we teach, do research, and consult. In this article, I give some examples of this from my 35 years as an academic statistician.

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“Teaching” In Honor Of Cliff Blair, Howard Stoker Nov 2004

“Teaching” In Honor Of Cliff Blair, Howard Stoker

Journal of Modern Applied Statistical Methods

In this article, I conceptualize teaching as the profession of facilitating and stimulating learning. As “teachers”, we help students acquire learning skills that they may expand on later in their life. I review fifteen principles that facilitate effective learning.

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Optimal Control Of Semilinear Evolution Inclusions Via Discrete Approximations, Boris S. Mordukhovich, Dong Wang Nov 2004

Optimal Control Of Semilinear Evolution Inclusions Via Discrete Approximations, Boris S. Mordukhovich, Dong Wang

Mathematics Research Reports

This paper studies a Mayer type optimal control problem with general endpoint constraints for semilinear unbounded evolution inclusions in reflexive and separable Banach spaces. First, we construct a sequence of discrete approximations to the original optimal control problem for evolution inclusions and prove that optimal solutions to discrete approximation problems uniformly converge to a given optimal solution for the original continuous-time problem. Then, based on advanced tools of generalized differentiation, we derive necessary optimality conditions for discrete-time problems under fairly general assumptions. Combining these results with recent achievements of variational analysis in infinite-dimensional spaces, we establish new necessary optimality conditions …

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A New Goodness-Of-Fit Test For Item Response Theory, John H. Neel Nov 2004

A New Goodness-Of-Fit Test For Item Response Theory, John H. Neel

Journal of Modern Applied Statistical Methods

Chi-square techniques for testing goodness-of-fit in item response theory are shown to give incorrect results. A new measure, CB, based on cumulants is proposed which avoids the arbitrary nature of interval creation found in chi-square techniques. The distribution of CB is estimated using Monte Carlo techniques and critical values for testing goodness-of-fit are given.

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Modeling Incomplete Longitudinal Data, Hakan Demirtas Nov 2004

Modeling Incomplete Longitudinal Data, Hakan Demirtas

Journal of Modern Applied Statistical Methods

This article presents a review of popular parametric, semiparametric and ad-hoc approaches for analyzing incomplete longitudinal data.

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Aligned Rank Tests As Robust Alternatives For Testing Interactions In Multiple Group Repeated Measures Designs With Heterogeneous Covariances, Xiaosheng Lei, Janet K. Holt, T. Mark Beasley Nov 2004

Aligned Rank Tests As Robust Alternatives For Testing Interactions In Multiple Group Repeated Measures Designs With Heterogeneous Covariances, Xiaosheng Lei, Janet K. Holt, T. Mark Beasley

Journal of Modern Applied Statistical Methods

Data simulation was used to investigate whether tests performed on aligned ranks (Beasley, 2002) could be used as robust alternatives to parametric methods for testing a split-plot interaction with non-normal data and heterogeneous covariance matrices. Results indicated the aligned rank method do not have any distinct advantage over parametric methods in this situation.

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Multivariate And Multistrata Nonparametric Tests: The Nonparametric Combination Method, Livio Corain, Luigi Salmaso Nov 2004

Multivariate And Multistrata Nonparametric Tests: The Nonparametric Combination Method, Livio Corain, Luigi Salmaso

Journal of Modern Applied Statistical Methods

Researchers and practitioners in many scientific disciplines and industrial fields are often faced with complex problems when dealing with comparisons between two or more groups using classical parametric methods. The data arising from real problems rarely are in agreement with stringent parametric assumptions. The NonParametric Combination (NPC) methodology frees the researcher from stringent assumptions of parametric methods and allows a more flexible analysis, both in terms of specification of multivariate hypotheses and in terms of the nature of the variables involved in the analysis. An outline of NPC methodology is given, along with case studies.

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On Comparison Of Hypothesis Tests In The Bayesian Framework Without Loss Function, Vladimir Gercsik, Mark Kelbert Nov 2004

On Comparison Of Hypothesis Tests In The Bayesian Framework Without Loss Function, Vladimir Gercsik, Mark Kelbert

Journal of Modern Applied Statistical Methods

The problem is how to compare the quality of different hypothesis tests in a Bayesian framework without introducing a loss function. Three different linear orders on the set of all possible hypothesis tests are studied. The most natural order estimates the Fisher information between indicators of event and decision.

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The President’S Problem, Jann-Huei Jinn Nov 2004

The President’S Problem, Jann-Huei Jinn

Journal of Modern Applied Statistical Methods

A solution is offered in response to a complex combination problem challenged by Blom, Englund, and Sandell (1998). The problem is to determine the probability that a random permutation of the word BILLCLINTON has no equal neighbors.

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A Conversation With R. Clifford Blair On The Occasion Of His Retirement, Shlomo S. Sawilowsky Nov 2004

A Conversation With R. Clifford Blair On The Occasion Of His Retirement, Shlomo S. Sawilowsky

Journal of Modern Applied Statistical Methods

An interview was conducted on 23 November 2003 with R. Clifford Blair on the occasion on his retirement from the University of South Florida. This article is based on that interview. Biographical sketches and images of members of his academic genealogy are provided.

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Micro-Auger Electron Spectroscopy Studies Of Chemical And Electronic Effects At Gan-Sapphire Interfaces, X. L. Sun, S. T. Bradley, G. H. Jessen, David C. Look, Richard J. Molnar, L. J. Brillson Nov 2004

Micro-Auger Electron Spectroscopy Studies Of Chemical And Electronic Effects At Gan-Sapphire Interfaces, X. L. Sun, S. T. Bradley, G. H. Jessen, David C. Look, Richard J. Molnar, L. J. Brillson

Physics Faculty Publications

We have used cross-sectional micro-Auger electron spectroscopy (AES), coupled with micro-cathodoluminescence (CLS) spectroscopy, in a UHV scanning electron microscope to probe the chemical and related electronic features of hydride vapor phase epitaxy GaN/sapphire interfaces on a nanometer scale. AES images reveal dramatic evidence for micron-scale diffusion of O from Al2O3 into GaN. Conversely, plateau concentrations of N can extend microns into the sapphire, corresponding spatially to a 3.8 eV defect emission and Auger chemical shifts attributed to Al-N-O complexes. Interface Al Auger signals extending into GaN indicates AlGaN alloy formation, consistent with a blue-shifted CLS local interface …

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As-Doped P-Type Zno Produced By An Evaporation/Sputtering Process, David C. Look, G. M. Renlund, R. H. Burgener, J. R. Sizelove Nov 2004

As-Doped P-Type Zno Produced By An Evaporation/Sputtering Process, David C. Look, G. M. Renlund, R. H. Burgener, J. R. Sizelove

Physics Faculty Publications

Strongly p-type ZnO is produced by the following sequence of steps: (1) evaporation of Zn3As2 on a fused-quartz substrate at 350 °C; and (2) sputtering of ZnO with substrate held at 450 °C. The electrical characteristics include: resistivity of 0.4 Ω cm, a mobility of 4 cm2∕V s, and a hole concentration of about 4×1018 cm−3. This resistivity is among the best (lowest) ever reported for p-type ZnO. Secondary-ion mass spectroscopic analysis gives an average As concentration about 5×1019 cm−3, and a simple one-band fit of the …

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Geodetic And Sconstraints On Some Seismogenic Zone Processes In Costa Rica, Edmundo Norabuena, Timothy H. Dixon, Susan Schwartz, Heather Deshon, Andrew Newman, Marino Protti, Victor Gonzalez, Leroy Dorman, Ernst R. Flueh, Paul Lundgren, Fred Pollitz, Dan Sampson Nov 2004

Geodetic And Sconstraints On Some Seismogenic Zone Processes In Costa Rica, Edmundo Norabuena, Timothy H. Dixon, Susan Schwartz, Heather Deshon, Andrew Newman, Marino Protti, Victor Gonzalez, Leroy Dorman, Ernst R. Flueh, Paul Lundgren, Fred Pollitz, Dan Sampson

School of Geosciences Faculty and Staff Publications

New seismic and geodetic data from Costa Rica provide insight into seismogenic zone processes in Central America, where the Cocos and Caribbean plates converge. Seismic data are from combined land and ocean bottom deployments in the Nicoya peninsula in northern Costa Rica and near the Osa peninsula in southern Costa Rica. In Nicoya, inversion of GPS data suggests two locked patches centered at 14 ± 2 and 39 ± 6 km depth. Interplate microseismicity is concentrated in the more freely slipping intermediate zone, suggesting that small interseismic earthquakes may not accurately outline the updip limit of the seismogenic zone, the …

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Appeal Rates And Outcomes In Tried And Nontried Cases: Further Exploration Of Anti-Plaintiff Appellate Outcomes, Theodore Eisenberg Nov 2004

Appeal Rates And Outcomes In Tried And Nontried Cases: Further Exploration Of Anti-Plaintiff Appellate Outcomes, Theodore Eisenberg

Cornell Law Faculty Publications

Federal data sets covering district court and appellate court civil cases for cases terminating in fiscal years 1988 through 2000 are analyzed. Appeals are filed in 10.9 percent of filed cases, and 21.0 percent of cases if one limits the sample to cases with a definitive judgment for plaintiff or defendant. The appeal rate is 39.6 percent in tried cases compared to 10.0 percent of nontried cases. For cases with definitive judgments, the appeal filing rate is 19.0 percent in nontried cases and 40.9 percent in tried cases. Tried cases with definitive judgments are appealed to a conclusion on the …

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Long-Residency Hydration, Cation Binding, And Dynamics Of Loop E/Helix Iv Rrna-L25 Protein Complex, Neocles B. Leontis, Kamila Réblová, Nad'a Špačková, Jaroslav Koča, Jiří Šponer Nov 2004

Long-Residency Hydration, Cation Binding, And Dynamics Of Loop E/Helix Iv Rrna-L25 Protein Complex, Neocles B. Leontis, Kamila Réblová, Nad'a Špačková, Jaroslav Koča, Jiří Šponer

Chemistry Faculty Publications

Molecular dynamics simulations of RNA-protein complex between Escherichia coli loop E/helix IV (LE/HeIV) rRNA and L25 protein reveal a qualitative agreement between the experimental and simulated structures. The major groove of LE is a prominent rRNA cation-binding site. Divalent cations rigidify the LE major groove geometry whereas in the absence of divalent cations LE extensively interacts with monovalent cations via inner-shell binding. The HeIV region shows bistability of its major groove explaining the observed differences between x-ray and NMR structures. In agreement with the experiments, the simulations suggest that helix-alpha1 of L25 is the least stable part of the protein. …

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Relaxation To Native Conformation Of A Bond-Fluctuating Protein Chain With Hydrophobic And Polar Nodes, Johan Bjursell, Ras B. Pandey Nov 2004

Relaxation To Native Conformation Of A Bond-Fluctuating Protein Chain With Hydrophobic And Polar Nodes, Johan Bjursell, Ras B. Pandey

Faculty Publications

The conformation and dynamics of a protein chain with hydrophobic and polar nodes are examined by the bond-fluctuation model using Monte Carlo simulations on a cubic lattice. The minimal (nearest neighbor) interaction leads to standard (self-avoiding walk) conformation, i.e., the scaling of the radius of gyration Rg with the molecular weight N Rg ∝ Nγ with γ ≃ 3/5/ Specific interactions with longer range and higher strength are needed to approach the native globular conformations with γ < 3/5. Relaxation into the globular ground state shows a weak power-law decay, i.e., Rg ∝ t-α, α ~ 0.06-0.12.

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The Industrial Symbiosis Research Symposium At Yale: Advancing The Study Of Industry And Environment, Marian Chertow, Weslynne Ashton, Radha Kuppalli Nov 2004

The Industrial Symbiosis Research Symposium At Yale: Advancing The Study Of Industry And Environment, Marian Chertow, Weslynne Ashton, Radha Kuppalli

Yale School of the Environment Publications Series

Industrial symbiosis (IS), a sub-field of industrial ecology, is principally concerned with the cooperative management of resource flows through networks of businesses as a means of approaching ecologically sustainable industrial activity. Isolated researchers in a broad range of disciplines have investigated industrial symbiosis from a variety of starting points without a common agenda. The Industrial Symbiosis Research Symposium was held in January 2004 at Yale University, bringing together more than 30 experts from 15 countries to discuss critical questions and issues in this emerging area.The purpose of the Symposium was to give researchers an opportunity to share their knowledge and …

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Intelligent, Pervasive And Context-Aware Promotion Delivery Framework For Wireless Mobile Devices, Karthik Harihar Nov 2004

Intelligent, Pervasive And Context-Aware Promotion Delivery Framework For Wireless Mobile Devices, Karthik Harihar

Theses and Dissertations

Mobile devices are now powerful systems and are the main vehicles for m- commerce. Market research predicts enormous potential for m-commerce applications and services [9], [10], [11], [12]. Unique features such as portability, location-awareness and personalization make mobile devices effective tools for targeted advertising. Several mobile marketing frameworks have been designed that deliver promotions based on location information and user preferences [3], [4], [5]. These frameworks have several drawbacks that need to be addressed in order to be effective. The aim of this thesis is to research a simple and efficient framework for targeted and personalized advertising. This work presents …

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