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2005

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Articles 331 - 360 of 4759

Full-Text Articles in Physical Sciences and Mathematics

Aid To The Identification Of Waterfowl Breastbones, Parts I & Ii, David Oates Nov 2005

Aid To The Identification Of Waterfowl Breastbones, Parts I & Ii, David Oates

Other Publications in Wildlife Management

This document provides information on identifying the species of waterfowl by means of breastbone characteristics (i.e., in skeletal remains). It contains diagrams, measurements, and distinguishing characteristics for the following species: oldsquaw, ruddy duck, black scoter, surf scoter, white-winged scoter, common eider, king eider, harlequin duck, canvasback, greater scaup, lesser scaup, redhead duck, ring-necked duck, common merganser, red-breasted merganser, hooded merganser, common goldeneye, Barrow's goldeneye, bufflehead, Steller's eider, whistling duck, tree duck, black-bellied duck, fulvous duck, blue-winged teal, cinnamon teal, green-winged teal, black duck, gadwall, mallard, mottled duck, pintail, shoveler, bald pate widgeon, and wood duck. A useful document for forensic …

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Laser-Powered Thermoelectric Generators Operating At Cryogenic Temperatures, S. R. Harutyunyan, V. H. Vardanyan, A. S. Kuzanyan, V. R. Nikoghosyan, S. Kunii, K. Winzer, K. S. Wood, Armen Gulian Nov 2005

Laser-Powered Thermoelectric Generators Operating At Cryogenic Temperatures, S. R. Harutyunyan, V. H. Vardanyan, A. S. Kuzanyan, V. R. Nikoghosyan, S. Kunii, K. Winzer, K. S. Wood, Armen Gulian

Mathematics, Physics, and Computer Science Faculty Articles and Research

A thermoelectric generator, operating in a cryostat at liquid helium temperatures, is described. Energy to the generator is supplied via an external laser beam. For this prototype device the associated heat load at permanent operation is comparable with the heat load associated with power delivery via metallic wires. Estimates indicate that still better performance can be enabled with existing thermoelectric materials, thereby far exceeding efficiency of traditional cryostat wiring. We used a prototype generator to produce electric power for measuring critical currents in Nb3Sn-films at 4K.

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Master’S Thesis Proposal: Computation Reuse In Stacking And Unstacking, Anne Loomis Nov 2005

Master’S Thesis Proposal: Computation Reuse In Stacking And Unstacking, Anne Loomis

Computer Science Technical Reports

Algorithms for dynamic simulation and control are fundamental to many applications, including computer games and movies, medical simulation, and mechanical design. I propose to explore efficient algorithms for finding a stable unstacking sequence -- an order in which we can remove every object from a structure without causing the structure to collapse under gravity at any step. We begin with a basic unstacking sequence algorithm: consider the set of all objects in a structure. Collect all possible subsets into a disassembly graph. Search the graph, testing the stability of each node as it is visited. Any path of stable nodes …

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Spontaneous Lorentz Violation And Nonpolynomial Interactions, Brett Altschul, V. Alan Kostelecký Nov 2005

Spontaneous Lorentz Violation And Nonpolynomial Interactions, Brett Altschul, V. Alan Kostelecký

Faculty Publications

Gauge-noninvariant vector field theories with superficially nonrenormalizable nonpolynomial interactions are studied. We show that nontrivial relevant and stable theories have spontaneous Lorentz violation, and we present a large class of asymptotically free theories. The Nambu-Goldstone modes of these theories can be identified with the photon, with potential experimental implications. © 2005 Elsevier B.V. All rights reserved.

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Semantics For Scientific Experiments And The Web: The Implicit, The Formal And The Powerful, Amit P. Sheth Nov 2005

Semantics For Scientific Experiments And The Web: The Implicit, The Formal And The Powerful, Amit P. Sheth

Kno.e.sis Publications

No abstract provided.

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Semiclassical Nonadiabatic Dynamics Using A Mixed Wave-Function Representation, Sophya Garashchuk, Vitaly A. Rassolov, George C. Schatz Nov 2005

Semiclassical Nonadiabatic Dynamics Using A Mixed Wave-Function Representation, Sophya Garashchuk, Vitaly A. Rassolov, George C. Schatz

Faculty Publications

Nonadiabatic effects in quantum dynamics are described using a mixed polar/coordinate space representation of the wave function. The polar part evolves on dynamically determined potential surfaces that have diabatic and adiabatic potentials as limiting cases of weak localized and strong extended diabatic couplings. The coordinate space part, generalized to a matrix form, describes transitions between the surfaces. Choice of the effective potentials for the polar part and partitioning of the wave function enables one to represent the total wave function in terms of smooth components that can be accurately propagated semiclassically using the approximate quantum potential and small basis sets. …

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Totally Real Galois Representations In Characteristic 2 And Arithmetic Cohomology, Heather Aurora Florence De Melo Nov 2005

Totally Real Galois Representations In Characteristic 2 And Arithmetic Cohomology, Heather Aurora Florence De Melo

Theses and Dissertations

The purpose of this paper is to provide new examples supporting a conjecture of Ash, Doud, and Pollack. This conjecture involves Galois representations taking Gal(Q bar/Q) to the general linear group of 3 x 3 matrices in characterisic 2, and our examples are where complex conjugation is mapped to the identity. Since this case has not yet been examined, the results of this paper are quite significant.

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Observations And Analysis Of Uncorrelated Rain, Michael L. Larsen, Alexander Kostinski, Ali Tokay Nov 2005

Observations And Analysis Of Uncorrelated Rain, Michael L. Larsen, Alexander Kostinski, Ali Tokay

Department of Physics Publications

Most microphysical models in precipitation physics and radar meteorology assume (at least implicitly) that raindrops are completely uncorrelated in space and time. Yet, several recent studies have indicated that raindrop arrivals are often temporally and spatially correlated. Resolution of this conflict must begin with observations of perfectly uncorrelated rainfall, should such “perfectly steady rain” exist at all. Indeed, it does. Using data with high temporal precision from a two-dimensional video disdrometer and the pair-correlation function, a scale-localized statistical tool, several ∼10–20-min rain episodes have been uncovered where no clustering among droplet arrival times is found. This implies that (i) rain …

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Coherence And Polarization Properties Of Far Fields Generated By Quasi-Homogeneous Planar Electromagnetic Sources, Olga Korotkova, Brian G. Hoover, Victor L. Gamiz, Emil Wolf Nov 2005

Coherence And Polarization Properties Of Far Fields Generated By Quasi-Homogeneous Planar Electromagnetic Sources, Olga Korotkova, Brian G. Hoover, Victor L. Gamiz, Emil Wolf

Physics Articles and Papers

In studies of radiation from partially coherent sources the so-called quasi-homogeneous (QH) model sources have been very useful, for instance in elucidating the behavior of fields produced by thermal sources. The analysis of the fields generated by such sources has, however, been largely carried out in the framework of scalar wave theory. In this paper we generalize the concept of the QH source to the domain of the electromagnetic theory, and we derive expressions for the elements of the cross-spectral density matrix, for the spectral density, the spectral degree of coherence, the degree of polarization, and the Stokes parameters of …

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Description Of A Database Support Tool For Retrospective Georeferencing Of Natural History Museum Specimen Collections, Rachel A. Simpson, Jeremy B. Young Nov 2005

Description Of A Database Support Tool For Retrospective Georeferencing Of Natural History Museum Specimen Collections, Rachel A. Simpson, Jeremy B. Young

School of Natural Resources: Faculty Publications

The locations at which natural history museum specimens were collected can be visualized using Geographic Information Systems (GIS) technology when explicit and standardized references to geospatial locations are available. We describe a database support tool which automates the association of localities with explicit geospatial coordinates for named places included in an electronic gazetteer. The tool furthermore facilitates simple manual review and correction of results.

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On The Action Of Weight-Preserving Sets, Matthew Badger Nov 2005

On The Action Of Weight-Preserving Sets, Matthew Badger

Mathematical Sciences Technical Reports (MSTR)

We introduce weight-preserving sets of binary words. Any transformation that respects the row and column weights of a 0-1 matrix can be decomposed as a composition of two types of action on the matrix. We conjecture that weight-preserving sets perform only one type of action, permutations of rows and columns; i.e., weight-preserving sets are cwatsets.

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Statistical Pronouncements Iv, Shlomo S. Sawilowsky Nov 2005

Statistical Pronouncements Iv, Shlomo S. Sawilowsky

Theoretical and Behavioral Foundations of Education Faculty Publications

No abstract provided.

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The Quartzite Problem Revisited, Jeffrey L. Howard Nov 2005

The Quartzite Problem Revisited, Jeffrey L. Howard

Environmental Science and Geology Faculty Research Publications

A review of past terminology and previous petrological studies suggests that quartzite should be classified descriptively as both a sedimentary and a metamorphic rock. Quartzite is identified in the field as a quartz‐rich rock (exclusive of chert and vein quartz) that is exceptionally hard and, when broken by a rock hammer, fractures irregularly through both grains and cement (where present) to form an irregular or conchoidal fracture surface. Quartzite is differentiated from quartzose sandstone (arenite), which is softer and fractures around individual grains, and from chert and vein quartz by a bright vitreous luster. Quartzite is classified further on the …

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Efficacy Studies Of Malaria Treatments In Africa: Efficient Estimation With Missing Indicators Of Failure, Rhoderick N. Machekano, Grant Dorsey, Alan E. Hubbard Nov 2005

Efficacy Studies Of Malaria Treatments In Africa: Efficient Estimation With Missing Indicators Of Failure, Rhoderick N. Machekano, Grant Dorsey, Alan E. Hubbard

U.C. Berkeley Division of Biostatistics Working Paper Series

Efficacy studies of malaria treatments can be plagued by indeterminate outcomes for some patients. The study motivating this paper defines the outcome of interest (treatment failure) as recrudescence and for some subjects, it is unclear whether a recurrence of malaria is due to that or new infection. This results in a specific kind of missing data. The effect of missing data in causal inference problems is widely recognized. Methods that adjust for possible bias from missing data include a variety of imputation procedures (extreme case analysis, hot-deck, single and multiple imputation), inverse weighting methods, and likelihood based methods (data augmentation, …

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The N2k Consortium. Ii. A Transiting Hot Saturn Around Hd 149026 With A Large Dense Core, Bun'ei Sato, Debra A. Fischer, Gregory W. Henry, Gregory Laughlin, R. Paul Butler, Geoffrey W. Marcy, Steve Vogt, Peter Bodenheimer, Shigeru Ida, Eri Toyota, Aaron S. Wolf, Jeff A. Valenti, Louis J. Boyd, John A. Johnson, Jason T. Wright, Mark Ammons, Sarah E. Robinson, Jay Strader, Chris Mccarthy, Kok Leong Tah, Dante Minniti Nov 2005

The N2k Consortium. Ii. A Transiting Hot Saturn Around Hd 149026 With A Large Dense Core, Bun'ei Sato, Debra A. Fischer, Gregory W. Henry, Gregory Laughlin, R. Paul Butler, Geoffrey W. Marcy, Steve Vogt, Peter Bodenheimer, Shigeru Ida, Eri Toyota, Aaron S. Wolf, Jeff A. Valenti, Louis J. Boyd, John A. Johnson, Jason T. Wright, Mark Ammons, Sarah E. Robinson, Jay Strader, Chris Mccarthy, Kok Leong Tah, Dante Minniti

Information Systems and Engineering Management Research Publications

Doppler measurements from Subaru and Keck have revealed radial velocity variations in the V = 8.15, G0 IV star HD 149026 consistent with a Saturn-mass planet in a 2.8766 day orbit. Photometric observations at Fairborn Observatory have detected three complete transit events with depths of 0.003 mag at the predicted times of conjunction. HD 149026 is now the second-brightest star with a transiting extrasolar planet. The mass of the star, based on interpolation of stellar evolutionary models, is 1.3 ± 0.1 M☉; together with the Doppler amplitude K1 = 43.3 m s-1, we derive a planet mass M sin i …

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Comparison Of Statistical Tests In Logistic Regression: The Case Of Hypernatreamia, Stylianos Katsaragakis, Christos Koukouvinos, Stella Stylianou, Eleni-Maria Theodoraki, Eleni-Maria Theodoraki Nov 2005

Comparison Of Statistical Tests In Logistic Regression: The Case Of Hypernatreamia, Stylianos Katsaragakis, Christos Koukouvinos, Stella Stylianou, Eleni-Maria Theodoraki, Eleni-Maria Theodoraki

Journal of Modern Applied Statistical Methods

The logistic regression has become an integral component of any medical data analysis concerning binary responses. The main issue rising after the adaptation of the final model is its goodness-of-fit. The fit of the model is assessed via the overall measures and summary statistics and comparing them in the case of hypernateamia.

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An Estimator Of Intervention Effect On Disease Severity, David Siev Nov 2005

An Estimator Of Intervention Effect On Disease Severity, David Siev

Journal of Modern Applied Statistical Methods

When a medical intervention prevents a dichotomous outcome, the size of its effect is often estimated with the prevented fraction. Some interventions may reduce the severity of an outcome without entirely preventing it. To quantify the effect of a severity-moderating intervention, a measure termed the mitigated fraction (MF) is proposed. MF has broad applicability, because it measures the overlap of two empirical distributions based on their stochastic ordering. It is also useful in the specific context of medical interventions, because it shares certain structural and functional features with the prevented fraction. The two measures may be applied together …

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Bootstrap Intervals Of The Parameters Of Lognormal Distribution Using Power Rule Model And Accelerated Life Tests, Mohammed Al-Haj Ebrahem Nov 2005

Bootstrap Intervals Of The Parameters Of Lognormal Distribution Using Power Rule Model And Accelerated Life Tests, Mohammed Al-Haj Ebrahem

Journal of Modern Applied Statistical Methods

Assumed that the distribution of the lifetime of any unit follows a lognormal distribution with parameters μ and σ . Also, assume that the relationship between μ and the stress level V is given by the power rule model. Several types of bootstrap intervals of the parameters were studied and their performance was studied using simulations and compared in term of attainment of the nominal confidence level, symmetry of lower and upper error rates and the expected width. Conclusions and recommendations are given.

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Large Sample And Bootstrap Intervals For The Gamma Scale Parameter Based On Grouped Data, Ayman Baklizi, Amjad Al-Nasser Nov 2005

Large Sample And Bootstrap Intervals For The Gamma Scale Parameter Based On Grouped Data, Ayman Baklizi, Amjad Al-Nasser

Journal of Modern Applied Statistical Methods

Interval estimation of the scale parameter of the gamma distribution using grouped data is considered in this article. Exact intervals do not exist and approximate intervals are needed Recently, Chen and Mi (2001) proposed alternative approximate intervals. In this article, some bootstrap and jackknife type intervals are proposed. The performance of these intervals is investigated and compared. The results show that some of the suggested intervals have a satisfactory statistical performance in situations where the sample size is small with heavy proportion of censoring.

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A Comparison Of The Spearman-Brown And Flanagan-Rulon Formulas For Split Half Reliability Under Various Variance Parameter Conditions, David A. Walker Nov 2005

A Comparison Of The Spearman-Brown And Flanagan-Rulon Formulas For Split Half Reliability Under Various Variance Parameter Conditions, David A. Walker

Journal of Modern Applied Statistical Methods

Differences between the Spearman-Brown and Flanagan-Rulon formulas are examined when the variance parameters for two halves of a test had the following ratios: 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0 and also had a correlation between the two halves of a test at 1.00, .95, .90, .80, .70, .60, .50, .40, .30, .20, .10, .05. It was found that use of the Spearman-Brown formula to estimate the population ρ when the ratio between the standard deviations on two halves of a test is disparate, or beyond .9 to 1.1, was not warranted. Applied and theoretical examples …

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Restricted Quasi-Independent Model Resolves Paradoxical Behaviors Of Cohen’S Kappa, Vicki Stover Hertzberg, Frank Xu, Michael Haber Nov 2005

Restricted Quasi-Independent Model Resolves Paradoxical Behaviors Of Cohen’S Kappa, Vicki Stover Hertzberg, Frank Xu, Michael Haber

Journal of Modern Applied Statistical Methods

Cohen’s kappa, an index of inter-rater agreement, behaves paradoxically in 2×2 tables. λA is derived, an index from the restricted quasi-independent model for 2×2 tables. Simulation studies are used to demonstrate λA has superior performance compared to Scott’s pi. Moreover, λA does not show paradoxical behavior for 2×2 tables.

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Maximum Tests Are Adaptive Permutation Tests, Markus Neuhäeuser, Ludwig A. Hothorn Nov 2005

Maximum Tests Are Adaptive Permutation Tests, Markus Neuhäeuser, Ludwig A. Hothorn

Journal of Modern Applied Statistical Methods

In some areas, e.g., statistical genetics, it is common to apply a maximum test, where the maximum of several competing test statistics is used as a new statistic, and the permutation distribution of the maximum is used for inference. Here, it is shown that maximum tests are special cases of adaptive permutation tests. The 30-year old idea of adaptive statistical tests is more flexible than previously thought when permutation tests are used, and the selector statistic is calculated for every permutation. Because the independence between the selector and the test statistics is no longer needed, the test statistics themselves can …

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Inferences About The Components Of A Generalized Additive Model, Rand R. Wilcox Nov 2005

Inferences About The Components Of A Generalized Additive Model, Rand R. Wilcox

Journal of Modern Applied Statistical Methods

A method for making inferences about the components of a generalized additive model is described. It is found that a variation of the method, based on means, performs well in simulations. Unlike many other inferential methods, switching from a mean to a 20% trimmed mean was found to offer little or no advantage in terms of both power and controlling the probability of a Type I error.

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The Individuals Control Chart In Case Of Non-Normality, BetüL Kan, Berna Yazici Nov 2005

The Individuals Control Chart In Case Of Non-Normality, BetüL Kan, Berna Yazici

Journal of Modern Applied Statistical Methods

This article examines the effects of non-normality as measured by skewness and provides an alternative method of designing individuals control chart with non-normal distributions. A skewness correction method for constructing the individuals control chart is provided. An example of thickness of biscuit process is presented to illustrate the individuals control chart limits.

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An Alternative To Warner’S Randomized Response Model, Sat Gupta, Javid Shabbir Nov 2005

An Alternative To Warner’S Randomized Response Model, Sat Gupta, Javid Shabbir

Journal of Modern Applied Statistical Methods

A modification to Warner’s (1965) Randomized Response Model is suggested. The suggested model is more efficient than the original model.

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Inference For P(Y, Vee Ming Ng Nov 2005

Inference For P(Y, Vee Ming Ng

Journal of Modern Applied Statistical Methods

Some tests and confidence bounds for the reliability parameter R=P(Y

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Determining Parallel Analysis Criteria, Marley W. Watkins Nov 2005

Determining Parallel Analysis Criteria, Marley W. Watkins

Journal of Modern Applied Statistical Methods

Determining the number of factors to extract is a critical decision in exploratory factor analysis. Simulation studies have found the Parallel Analysis criterion to be accurate, but it is computationally intensive. Two freeware programs that implement Parallel Analysis on Macintosh and Windows operating systems are presented.

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Change Point Estimation Of Bilevel Functions, Leming Qu, Yi-Cheng Tu Nov 2005

Change Point Estimation Of Bilevel Functions, Leming Qu, Yi-Cheng Tu

Journal of Modern Applied Statistical Methods

Reconstruction of a bilevel function such as a bar code signal in a partially blind deconvolution problem is an important task in industrial processes. Existing methods are based on either the local approach or the regularization approach with a total variation penalty. This article reformulated the problem explicitly in terms of change points of the 0-1 step function. The bilevel function is then reconstructed by solving the nonlinear least squares problem subject to linear inequality constraints, with starting values provided by the local extremas of the derivative of the convolved signal from discrete noisy data. Simulation results show a considerable …

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Correlation Between The Number Of Epileptic And Healthy Children In Family Size That Follows A Size-Biased Modified Power Series Distribution, Ramalingam Shanmugam, Anwar Hassan, Peer Bilal Ahmad Nov 2005

Correlation Between The Number Of Epileptic And Healthy Children In Family Size That Follows A Size-Biased Modified Power Series Distribution, Ramalingam Shanmugam, Anwar Hassan, Peer Bilal Ahmad

Journal of Modern Applied Statistical Methods

An expression for the correlation between the random number of epileptic and healthy children in family whose size follows a size-biased Modified Power Series Distribution (SBMPSD) is obtained and illustrated. As special cases, results are extracted for size biased Modified Negative Binomial Distribution (SBGNBD), size biased Modified Poisson Distribution (SBGPD) and size biased Modified Logarithmic Series Distribution (SBGLSD).

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Simulation Of Non-Normal Autocorrelated Variables, H.E.T. Holgersson Nov 2005

Simulation Of Non-Normal Autocorrelated Variables, H.E.T. Holgersson

Journal of Modern Applied Statistical Methods

All statistical methods rely on assumptions to some extent. Two assumptions frequently met in statistical analyses are those of normal distribution and independence. When examining robustness properties of such assumptions by Monte Carlo simulations it is therefore crucial that the possible effects of autocorrelation and non-normality are not confounded so that their separate effects may be investigated. This article presents a number of non-normal variables with non-confounded autocorrelation, thus allowing the analyst to specify autocorrelation or shape properties while keeping the other effect fixed.

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