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2004

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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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Probabilities As Similarity-Weighted Frequencies, Antoine Billot, Itzhak Gilboa, Dov Samet, David Schmeidler Nov 2004

Probabilities As Similarity-Weighted Frequencies, Antoine Billot, Itzhak Gilboa, Dov Samet, David Schmeidler

Cowles Foundation Discussion Papers

A decision maker is asked to express her beliefs by assigning probabilities to certain possible states. We focus on the relationship between her database and her beliefs. We show that, if beliefs given a union of two databases are a convex combination of beliefs given each of the databases, the belief formation process follows a simple formula: beliefs are a similarity-weighted average of the beliefs induced by each past case.

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Rule-Based And Case-Based Reasoning In Housing Prices, Gabrielle Gayer, Itzhak Gilboa, Offer Lieberman Nov 2004

Rule-Based And Case-Based Reasoning In Housing Prices, Gabrielle Gayer, Itzhak Gilboa, Offer Lieberman

Cowles Foundation Discussion Papers

People reason about real-estate prices both in terms of general rules and in terms of analogies to similar cases. We propose to empirically test which mode of reasoning fits the data better. To this end, we develop the statistical techniques required for the estimation of the case-based model. It is hypothesized that case-based reasoning will have relatively more explanatory power in databases of rental apartments, whereas rule-based reasoning will have a relative advantage in sales data. We motivate this hypothesis on theoretical grounds, and find empirical support for it by comparing the two statistical techniques (rule-based and case-based) on two …

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Real Delay Graphical Probabilistic Switching Model For Vlsi Circuits, Vivekanandan Srinivasan Nov 2004

Real Delay Graphical Probabilistic Switching Model For Vlsi Circuits, Vivekanandan Srinivasan

USF Tampa Graduate Theses and Dissertations

Power optimization is a crucial issue at all levels of abstractions in VLSI Design. Power estimation has to be performed repeatedly to explore the design space throughout the design process at all levels. Dynamic Power Dissipation due to Switching Activity has been one of the major concerns in Power Estimation. While many Simulation and Statistical Simulation based methods exist to estimate Switching Activity, these methods are input pattern sensitive, hence would require a large input vector set to accurately estimate Power. Probabilistic estimation of switching activity under Zero-Delay conditions, seriously undermines the accuracy of the estimation process, since it fails …

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Behavioral Vhdl Implementation Of Coherent Digital Gps Signal Receiver, Viswanath Daita Nov 2004

Behavioral Vhdl Implementation Of Coherent Digital Gps Signal Receiver, Viswanath Daita

USF Tampa Graduate Theses and Dissertations

Global Positioning System is a technology which is gaining acceptance. Originally developed for military purposes, it is being used in civilian applications such as navigation, emergency services, etc. A system-on-chip application merges different functions and applications on a single substrate. This project models a GPS receiver for a system on chip application. The GPS receiver, developed as a core, is intended to be a part of a navigation tour guide being developed. The scope of this work is the GPS C/A code on the L1 carrier. The digital signal processing back-end in a GPS receiver is modelled in this work. …

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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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Our Selma Is Here: The Political And Legal Struggle For Educational Equality In Denver, Colorado, And Multiracial Conundrums In American Jurisprudence, Tom I. Romero Ii Nov 2004

Our Selma Is Here: The Political And Legal Struggle For Educational Equality In Denver, Colorado, And Multiracial Conundrums In American Jurisprudence, Tom I. Romero Ii

Seattle Journal for Social Justice

No abstract provided.

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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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End Matter, Jmasm Editors Nov 2004

End Matter, Jmasm Editors

Journal of Modern Applied Statistical Methods

No abstract provided.

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Vol. 3, No. 2 (Full Issue), Jmasm Editors Nov 2004

Vol. 3, No. 2 (Full Issue), Jmasm Editors

Journal of Modern Applied Statistical Methods

No abstract provided.

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A Survey Of Wpa And 802.11i Rsn Authentication Protocols, Kwang-Hyun Baek, Sean W. Smith, David Kotz Nov 2004

A Survey Of Wpa And 802.11i Rsn Authentication Protocols, Kwang-Hyun Baek, Sean W. Smith, David Kotz

Computer Science Technical Reports

In the new standards for WLAN security, many choices exist for the authentication process. In this paper, we list eight desired properties of WLAN authentication protocols, survey eight recent authentication protocols, and analyze the protocols according to the desired properties.

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Arts And Sciences Newsletter, Volume 8, Issue 3, College Of Arts & Sciences Nov 2004

Arts And Sciences Newsletter, Volume 8, Issue 3, College Of Arts & Sciences

Arts and Sciences Newsletters

No abstract provided.

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Plant Pigment Types, Distributions, And Influences On Shallow Water Submerged Aquatic Vegetation Mapping, Carlton R. Hall, Charles R. Bostater Jr., Robert Virnstein Nov 2004

Plant Pigment Types, Distributions, And Influences On Shallow Water Submerged Aquatic Vegetation Mapping, Carlton R. Hall, Charles R. Bostater Jr., Robert Virnstein

Ocean Engineering and Marine Sciences Faculty Publications

Development of robust protocols for use in mapping shallow water habitats using hyperspectral imagery requires knowledge of absorbing and scattering features present in the environment. These include, but are not limited to, water quality parameters, phytoplankton concentrations and species, submerged aquatic vegetation (SAV) species and densities, epiphytic growth on SAV, benthic microalgae and substrate reflectance characteristics. In the Indian River Lagoon, Fl. USA we conceptualize the system as having three possible basic layers, water column and SAV bed above the bottom. Each layer is occupied by plants with their associated light absorbing pigments that occur in varying proportions and concentrations. …

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Grand Valley Forum, Volume 029, Number 14, November 1, 2004, Grand Valley State University Nov 2004

Grand Valley Forum, Volume 029, Number 14, November 1, 2004, Grand Valley State University

2004-2005, Volume 29

Grand Valley Forum is Grand Valley State's faculty and staff newsletter, published from 1976 to the present.

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Integrated Coverage And Connectivity Configuration For Energy Conservation In Sensor Networks, Guoliang Xing, Xiaorui Wang, Yuanfang Zhang, Chenyang Lu, Robert Pless, Christopher Gill Nov 2004

Integrated Coverage And Connectivity Configuration For Energy Conservation In Sensor Networks, Guoliang Xing, Xiaorui Wang, Yuanfang Zhang, Chenyang Lu, Robert Pless, Christopher Gill

All Computer Science and Engineering Research

An effective approach for energy conservation in wireless sensor networks is scheduling sleep intervals for extraneous nodes, while the remaining nodes stay active to provide continuous service. For the sensor network to operate successfully, the active nodes must maintain both sensing coverage and network connectivity. Fur-thermore, the network must be able to configure itself to any feasible degrees of coverage and connectivity in order to support different applications and environments with diverse requirements. This paper presents the design and analysis of novel protocols that can dynamically configure a network to achieve guaranteed degrees of coverage and connectivity. This work differs …

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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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Using The Wacc To Value Real Options, Tom Arnold, Timothy Falcon Crack Nov 2004

Using The Wacc To Value Real Options, Tom Arnold, Timothy Falcon Crack

Finance Faculty Publications

We present a real option valuation using the weighted average cost of capital (WACC). This is an alternative to risk-neutral real option valuation. Using the WACC involves a marginal increase in mathematical complexity, but it is easy to implement in a spreadsheet, and it is easy to present to management. Our analysis reveals, however, that because the real option valuation is immune to choices of admissible discount rates (as per Arnold and Crack 2003a), the critical issue is correct estimation of volatility, not choice of discount rate. We also point out that the natural and conservative tendency to overestimate risk …

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War Fever Symposium:, Geoffrey R. Stone Nov 2004

War Fever Symposium:, Geoffrey R. Stone

Missouri Law Review

As Justice Robert Jackson observed more than half a century ago, “[i]t is easy, by giving way to the passion, intolerance and suspicion of wartime, to reduce our liberties to a shadow, often in answer to exaggerated claims of security.” Indeed, the United States has a long and unfortunate history of overreacting to the dangers of wartime. Again and again, Americans have allowed fear to the better of them. Some measure of fear, of course, is inevitable—even healthy—in time of war. Otherwise, it would be difficult, if not impossible, for a nation to make the sacrifices war demands. An essential …

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