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2006

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Articles 3001 - 3030 of 5872

Full-Text Articles in Physical Sciences and Mathematics

Prediction Of The Temporal Evolution Of Solar X-Ray Flares, Aaron J. Williams Mar 2006

Prediction Of The Temporal Evolution Of Solar X-Ray Flares, Aaron J. Williams

Theses and Dissertations

A solar flare is an explosive release of stored magnetic energy on the Sun. Much of this energy is converted into x-ray photons which escape into space. As a solar flare begins, the 1-8 Å x-ray photon flux at Earth’s orbit, as measured by the GOES satellite, rapidly increases. It quickly reaches a peak and slowly decays. A plot of this flux exhibits an approximate lognormal shape. A lognormal function becomes a normal, symmetric, function when the logarithm of the independent variable is taken. Once the peak flux is reached, this symmetry is used to make a prediction of the …

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A 2200-Year Record Of Hydrologic Variability From Foy Lake, Montana, Usa, Inferred From Diatom And Geochemical Data, Lora R. Stevens, Jeffery R. Stone, Josh Campbell, Sherilyn C. Fritz Mar 2006

A 2200-Year Record Of Hydrologic Variability From Foy Lake, Montana, Usa, Inferred From Diatom And Geochemical Data, Lora R. Stevens, Jeffery R. Stone, Josh Campbell, Sherilyn C. Fritz

Department of Earth and Atmospheric Sciences: Faculty Publications

A 2200-yr long, high-resolution (~5 yr) record of drought variability in northwest Montana is inferred from diatoms and δ18O values of bio-induced carbonate preserved in a varved lacustrine core from Foy Lake. A previously developed model of the diatom response to lake-level fluctuations is used to constrain estimates of paleolake levels derived from the diatom data. High-frequency (decadal) fluctuations in the de-trended δ18O record mirror variations in wet/dry cycles inferred from Banff tree-rings, demonstrating the sensitivity of the oxygen-isotope values to changes in regional moisture balance. Low frequency (multi-centennial) isotopic changes may be associated with shifts …

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Virginia Wetlands Report Vol. 21, No. 1, Virginia Institute Of Marine Science, Center For Coastal Resources Management Mar 2006

Virginia Wetlands Report Vol. 21, No. 1, Virginia Institute Of Marine Science, Center For Coastal Resources Management

Virginia Wetlands Reports

Integrated Coastal & Shoreline Management Guidance

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Nanomagnetic Models, Ralph Skomski, Jian Zhou Mar 2006

Nanomagnetic Models, Ralph Skomski, Jian Zhou

Ralph Skomski Publications

The atomic-scale and mesoscopic physics of magnetic nanostructures is reviewed. Emphasis is on the description of magnetic phenomena and properties by analytical models, as contrasted to numerical approaches. Nanostructuring affects the magnetic properties on different length scales, from a few interatomic distances for intrinsic properties such as magnetization and anisotropy to more than 10 nm for extrinsic properties, such as coercivity. The consideration includes static and dynamic mechanisms, as well as nanoscale finite-temperature effects. Some explicitly discussed examples are Curie- temperature changes due to nanostructuring, the effect of narrow and constricted walls, the potential use of magnetic nanodots for finite-temperature …

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Test-Driven Learning: Intrinsic Integration Of Testing Into The Cs/Se Curriculum, David S. Janzen, Hossein Saiedian Mar 2006

Test-Driven Learning: Intrinsic Integration Of Testing Into The Cs/Se Curriculum, David S. Janzen, Hossein Saiedian

Computer Science and Software Engineering

Test-driven learning (TDL) is an approach to teaching computer programming that involves introducing and exploring new concepts through automated unit tests. TDL offers the potential of teaching testing for free, of improving programmer comprehension and ability, and of improving software quality both in terms of design quality and reduced defect density.This paper introduces test-driven learning as a pedagogical tool. It will provide examples of how TDL can be incorporated at multiple levels in computer science and software engineering curriculum for beginning through professional programmers. In addition, the relationships between TDL and test-driven development will be explored.Initial evidence indicates that TDL …

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[Review Of] Stable Isotopes And Biosphere–Atmosphere Interactions: Processes And Biological Controls, Mark S. Coyne Mar 2006

[Review Of] Stable Isotopes And Biosphere–Atmosphere Interactions: Processes And Biological Controls, Mark S. Coyne

Plant and Soil Sciences Faculty Publications

No abstract provided.

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Maturity Assessment Framework For Business Dimension Of Software Product Family, Faheem Ahmed, Luiz Fernando Capretz Mar 2006

Maturity Assessment Framework For Business Dimension Of Software Product Family, Faheem Ahmed, Luiz Fernando Capretz

Electrical and Computer Engineering Publications

The software product family approach aims at curtailing the concept of “reinventing the wheel” in the software development process. The business has been highlighted as one of the critical dimensions in the process of software product family. This work presents an assessment framework for evaluating the business dimension of software product family process. Additionally, a software product family business evaluation tool has been designed and implemented on the basis of the presented framework. The tool preprocesses the data of key business factors, and it evaluates the overall business maturity of an organization. To demonstrate the application of the framework, and …

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Interferometric Studies Of A Piano Soundboard, Thomas R. Moore, Sarah A. Zietlow Mar 2006

Interferometric Studies Of A Piano Soundboard, Thomas R. Moore, Sarah A. Zietlow

Student-Faculty Collaborative Research Publications

Electronic speckle pattern interferometry has been used to study the deflection shapes of a piano soundboard. A design for an interferometer that can image such an unstable object is introduced, and interferograms of a piano soundboard obtained using this interferometer are presented. Deflection shapes are analyzed and compared to a finite element model, and it is shown that the force the strings exert on the soundboard is important in determining the mode shapes and resonant frequencies. Measurements of resonance frequencies and driving point impedance made using the interferometer are also presented.

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Southeast Florida Coral Reef Evaluation And Monitoring Project 2005 Year 3 Final Report, Jennifer Wheaton, Carl Beaver, Walter Jaap, Michael Callahan, Selena Kupfner, Shannon Wade, David S. Gilliam, B. D. Ettinger, Daniel P. Fahy, Shaun M. Gill, Lindsey Habakuk Klink, Jamie A. Monty, M. A. Philips, Lauren F. Shuman, Nicole R. Stephens, Brian K. Walker, Joanna C. Walczak, Richard E. Dodge, Tim Mcintosh, Steven Blair, Kenneth Banks, Louis E. Fisher, David Stout, Joe Ligas, Janet Phipps Mar 2006

Southeast Florida Coral Reef Evaluation And Monitoring Project 2005 Year 3 Final Report, Jennifer Wheaton, Carl Beaver, Walter Jaap, Michael Callahan, Selena Kupfner, Shannon Wade, David S. Gilliam, B. D. Ettinger, Daniel P. Fahy, Shaun M. Gill, Lindsey Habakuk Klink, Jamie A. Monty, M. A. Philips, Lauren F. Shuman, Nicole R. Stephens, Brian K. Walker, Joanna C. Walczak, Richard E. Dodge, Tim Mcintosh, Steven Blair, Kenneth Banks, Louis E. Fisher, David Stout, Joe Ligas, Janet Phipps

Marine & Environmental Sciences Faculty Reports

No abstract provided.

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A Fish Habitat Classification Model For The Upper And Middle Sections Of The Bay Of Quinte, Lake Ontario, C. K. Minns, Andrea Bernard, C. N. Bakelaar, M. Ewaschuk Mar 2006

A Fish Habitat Classification Model For The Upper And Middle Sections Of The Bay Of Quinte, Lake Ontario, C. K. Minns, Andrea Bernard, C. N. Bakelaar, M. Ewaschuk

Marine & Environmental Sciences Faculty Reports

A fish habitat classification model was developed and applied to the upper and middle sections of the Bay of Quinte, Lake Ontario. Available habitat inventories were assembled in a GIS database, bringing bathymetric, shoreline, substrate, and vegetation data together in a series of layers. The classification model was developed in four steps. In the first step, the Defensible Methods (DM) model developed by Minns et al. (2000) was used to estimate suitability values in all habitat patches for a set of nine fish groups each with three life stages. The fish groups were formed from the assemblage of fish species …

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Kenneth Bloom: Curriculum Vitae Mar 2006

Kenneth Bloom: Curriculum Vitae

Kenneth Bloom Publications

Current as of March 2006. 5 pages. Includes abbreviated list of publications.

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Optimization And Equilibrium Problems With Equilibrium Constraints In Infinite-Dimensional Spaces, Boris S. Mordukhovich Mar 2006

Optimization And Equilibrium Problems With Equilibrium Constraints In Infinite-Dimensional Spaces, Boris S. Mordukhovich

Mathematics Research Reports

The paper is devoted to applications of modern variational f).nalysis to the study of constrained optimization and equilibrium problems in infinite-dimensional spaces. We pay a particular attention to the remarkable classes of optimization and equilibrium problems identified as MPECs (mathematical programs with equilibrium constraints) and EPECs (equilibrium problems with equilibrium constraints) treated from the viewpoint of multiobjective optimization. Their underlying feature is that the major constraints are governed by parametric generalized equations/variational conditions in the sense of Robinson. Such problems are intrinsically nonsmooth and can be handled by using an appropriate machinery of generalized differentiation exhibiting a rich/full calculus. The …

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Shrinkage Estimation For Sage Data Using A Mixture Dirichlet Prior, Jeffrey S. Morris, Keith A. Baggerly, Kevin R. Coombes Mar 2006

Shrinkage Estimation For Sage Data Using A Mixture Dirichlet Prior, Jeffrey S. Morris, Keith A. Baggerly, Kevin R. Coombes

Jeffrey S. Morris

Serial Analysis of Gene Expression (SAGE) is a technique for estimating the gene expression profile of a biological sample. Any efficient inference in SAGE must be based upon efficient estimates of these gene expression profiles, which consist of the estimated relative abundances for each mRNA species present in the sample. The data from SAGE experiments are counts for each observed mRNA species, and can be modeled using a multinomial distribution with two characteristics: skewness in the distribution of relative abundances and small sample size relative to the dimension. As a result of these characteristics, a given SAGE sample will fail …

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Globalization & Nationalism: A Recipe For Terror, Cari Bourette, Daniel Reader Mar 2006

Globalization & Nationalism: A Recipe For Terror, Cari Bourette, Daniel Reader

Cari Bourette

Nationalism appears to be part of the human condition; it may well be related to the human tendency toward tribalism. Whatever the case, nationalism appears to be a permanent feature on the global landscape. Globalization, while not a new phenomenon by any means, seems to be having a tremendous dilutory effect on the sovereignty of states; it now appears to be carrying the assault to the cultural frontiers of nationalism. Unlike the Westphalian constructs, however, nations will not so easily succumb. There is a greater inherent resistance to change in nations; the only historically effective method has been outright eradication …

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An Introduction To High-Throughput Bioinformatics Data, Keith A. Baggerly, Kevin R. Coombes, Jeffrey S. Morris Mar 2006

An Introduction To High-Throughput Bioinformatics Data, Keith A. Baggerly, Kevin R. Coombes, Jeffrey S. Morris

Jeffrey S. Morris

High throughput biological assays supply thousands of measurements per sample, and the sheer amount of related data increases the need for better models to enhance inference. Such models, however, are more effective if they take into account the idiosyncracies associated with the specific methods of measurement: where the numbers come from. We illustrate this point by describing three different measurement platforms: microarrays, serial analysis of gene expression (SAGE), and proteomic mass spectrometry.

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Bayesian Mixture Models For Gene Expression And Protein Profiles, Michele Guindani, Kim-Anh Do, Peter Mueller, Jeffrey S. Morris Mar 2006

Bayesian Mixture Models For Gene Expression And Protein Profiles, Michele Guindani, Kim-Anh Do, Peter Mueller, Jeffrey S. Morris

Jeffrey S. Morris

We review the use of semi-parametric mixture models for Bayesian inference in high throughput genomic data. We discuss three specific approaches for microarray data, for protein mass spectrometry experiments, and for SAGE data. For the microarray data and the protein mass spectrometry we assume group comparison experiments, i.e., experiments that seek to identify genes and proteins that are differentially expressed across two biologic conditions of interest. For the SAGE data example we consider inference for a single biologic sample.

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Analysis Of Mass Spectrometry Data Using Bayesian Wavelet-Based Functional Mixed Models, Jeffrey S. Morris, Philip J. Brown, Keith A. Baggerly, Kevin R. Coombes Mar 2006

Analysis Of Mass Spectrometry Data Using Bayesian Wavelet-Based Functional Mixed Models, Jeffrey S. Morris, Philip J. Brown, Keith A. Baggerly, Kevin R. Coombes

Jeffrey S. Morris

In this chapter, we demonstrate how to analyze MALDI-TOF/SELDITOF mass spectrometry data using the wavelet-based functional mixed model introduced by Morris and Carroll (2006), which generalizes the linear mixed models to the case of functional data. This approach models each spectrum as a function, and is very general, accommodating a broad class of experimental designs and allowing one to model nonparametric functional effects for various factors, which can be conditions of interest (e.g. cancer/normal) or experimental factors (blocking factors). Inference on these functional effects allows us to identify protein peaks related to various outcomes of interest, including dichotomous outcomes, categorical …

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Economic And Energy Aspects Of Motor Vehicle Taxation, Theodoros Zachariadis, Nadia Nicolaidou Mar 2006

Economic And Energy Aspects Of Motor Vehicle Taxation, Theodoros Zachariadis, Nadia Nicolaidou

Theodoros Zachariadis

No abstract provided.

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Multiple Tests Of Association With Biological Annotation Metadata, Sandrine Dudoit, Sunduz Keles, Mark J. Van Der Laan Mar 2006

Multiple Tests Of Association With Biological Annotation Metadata, Sandrine Dudoit, Sunduz Keles, Mark J. Van Der Laan

U.C. Berkeley Division of Biostatistics Working Paper Series

We propose a general and formal statistical framework for the multiple tests of associations between known fixed features of a genome and unknown parameters of the distribution of variable features of this genome in a population of interest. The known fixed gene-annotation profiles, corresponding to the fixed features of the genome, may concern Gene Ontology (GO) annotation, pathway membership, regulation by particular transcription factors, nucleotide sequences, or protein sequences. The unknown gene-parameter profiles, corresponding to the variable features of the genome, may be, for example, regression coefficients relating genome-wide transcript levels or DNA copy numbers to possibly censored biological and …

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A Diagnostic Test For The Mixing Distribution In A Generalised Linear Mixed Model, Eric J. Tchetgen, Brent A. Coull Mar 2006

A Diagnostic Test For The Mixing Distribution In A Generalised Linear Mixed Model, Eric J. Tchetgen, Brent A. Coull

Harvard University Biostatistics Working Paper Series

We introduce a diagnostic test for the mixing distribution in a generalised linear mixed model. The test is based on the difference between the marginal maximum likelihood and conditional maximum likelihood estimates of a subset of the fixed effects in the model. We derive the asymptotic variance of this difference, and propose a test statistic that has a limiting chi-square distribution under the null hypothesis that the mixing distribution is correctly specified. For the important special case of the logistic regression model with random intercepts, we evaluate via simulation the power of the test in finite samples under several alternative …

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Evaluating The Predictiveness Of A Continuous Marker, Ying Huang, Margaret S. Pepe, Ziding Feng Mar 2006

Evaluating The Predictiveness Of A Continuous Marker, Ying Huang, Margaret S. Pepe, Ziding Feng

UW Biostatistics Working Paper Series

Consider a continuous marker for predicting a binary outcome. For example, serum concentration of prostate specific antigen (PSA) may be used to calculate the risk of finding prostate cancer in a biopsy. In this paper we argue that the predictive capacity of a marker has to do with the population distribution of risk given the marker and suggest a graphical tool, the predictiveness curve, that displays this distribution. The display provides a common meaningful scale for comparing markers that may not be comparable on their original scales. Some existing measures of predictiveness are shown to be summary indices derived from …

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Stability Of The Gyroid Phase In Diblock Copolymers At Strong Segregation, Eric W. Cochran, Carlos J. Garcia-Cervera, Glenn H. Fredrickson Mar 2006

Stability Of The Gyroid Phase In Diblock Copolymers At Strong Segregation, Eric W. Cochran, Carlos J. Garcia-Cervera, Glenn H. Fredrickson

Eric W. Cochran

The gyroid phase in diblock copolymers at strong segregation was stabilized. The intriguing topology of the network structure has inspired a diverse array of potential applications ranging from high-performance separation membranes to photonic crystals. The pressure field enforces incompressibility, while the exchange field is conjugate to the composition pattern in the melt. The Laplacian operator is treated implicitly with a fourth-order backward differentiation formula (BDF4), whereas the source term is discretized explicitly using fourth-order accurate Adams-Bashford.

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Scalar Mesons In D And B Decays, Stefan Spanier Mar 2006

Scalar Mesons In D And B Decays, Stefan Spanier

stefan spanier

The decays of D and B mesons provide new insights into the natur of light scalar mesons. Several recent measurements are presented.

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A Simple Computational Method For The Identification Of Disease-Associated Loci In Complex, Incomplete Pedigrees, Gregory Leibon, Dan Rockmore, Martin R. Pollak Mar 2006

A Simple Computational Method For The Identification Of Disease-Associated Loci In Complex, Incomplete Pedigrees, Gregory Leibon, Dan Rockmore, Martin R. Pollak

Computer Science Technical Reports

We present an approach, called the Shadow Method, for the identification of disease loci from dense genetic marker maps in complex, potentially incomplete pedigrees. Shadow is a simple method based on an analysis of the patterns of obligate meiotic recombination events in genotypic data. This method can be applied to any high density marker map and was specifically designed to explore the fact that extremely dense marker maps are becoming more readily available. We also describe how to interpret and associated meaningful P-Values to the results. Shadow has significant advantages over traditional parametric linkage analysis methods in that it can …

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Spectroscopy And Photometry Of The Double-Lined Binary Hd 149420, Francis C. Fekel, Gregory W. Henry Mar 2006

Spectroscopy And Photometry Of The Double-Lined Binary Hd 149420, Francis C. Fekel, Gregory W. Henry

Information Systems and Engineering Management Research Publications

We have used new spectroscopic and photometric observations of HD 149420 to obtain an improved orbital element solution and determine some basic properties of the system. This double-lined binary has an orbital period of 3.39430 days, a circular orbit, and a mass ratio of 0.52. The primary is somewhat evolved, with an A9 IV spectral type, while the secondary is estimated to be an F5: dwarf. The secondary may be synchronously rotating, but the primary is rotating substantially slower than its synchronous velocity. Our photometric observations confirm the light variability and period found by Hipparcos. We determine a photometric period …

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Scwds Briefs: Volume 22, Number 1 (April 2006), Michael J. Yabsley Mar 2006

Scwds Briefs: Volume 22, Number 1 (April 2006), Michael J. Yabsley

Southeastern Cooperative Wildlife Disease Study: Publications

Avian Influenza Update - May 2006: 207 human cases, 115 fatalities. HPAI H5N1 virus has been detected in wild birds in Denmark, France, Germany, Sweden, the United Kingdom, and other European countries.
SCWDS remains actively involved in several field and laboratory studies investigating the ecology of avian influenza virus (AIV), including both high pathogenicity viruses (HPAI) and low pathogenicity viruses (LPAI).
A plan to conduct a survey of avian influenza (AI) viruses in wild birds in Canada was developed late in 2004 by the Canadian Cooperative Wildlife Health Centre (CCWHC) in consultation with a wide range of federal and provincial …

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Significant Association Between Punitive And Compensatory Damages In Blockbuster Cases: A Methodological Primer, Theodore Eisenberg, Martin T. Wells Mar 2006

Significant Association Between Punitive And Compensatory Damages In Blockbuster Cases: A Methodological Primer, Theodore Eisenberg, Martin T. Wells

Cornell Law Faculty Publications

This article assesses the relation between punitive and compensatory damages in a data set, gathered by Hersch and Viscusi (H-V), consisting of all known punitive damages awards in excess of $100 million from 1985 through 2003. It shows that a strong, statistically significant relation exists between punitive and compensatory awards, a relation that replicates similar findings in nearly all other analyses of punitive and compensatory damages. H-V's claim that no significant relation exists between punitive and compensatory awards in these data appears to be an artifact of questionable regression methodology.

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Refuge Update – March/April 2006, Volume 3, Number 2 Mar 2006

Refuge Update – March/April 2006, Volume 3, Number 2

RefugeUpdate (USFWS-NWRS)

Table of Contents:
Energy Company Fine Benefits Ottawa Refuge, page 3
Hide and Seek…but Mostly Hide page 4
Focus on …Pollinators, page 10
Great Storytellers, page 18

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Fortifying Password Authentication In Integrated Healthcare Delivery Systems, Yanjiang Yang, Robert H. Deng, Feng Bao Mar 2006

Fortifying Password Authentication In Integrated Healthcare Delivery Systems, Yanjiang Yang, Robert H. Deng, Feng Bao

Research Collection School Of Computing and Information Systems

Integrated Delivery Systems (IDSs) now become a primary means of care provision in healthcare domain. However, existing password systems (under either the single-server model or the multi-server model) do not provide adequate security when applied to IDSs. We are thus motivated to present a practical password authentication system built upon a novel two-server model. We generalize the two-server model to an architecture of a single control server supporting multiple service servers, tailored to the organizational structure of IDSs. The underlying user authentication and key exchange protocols we propose are password-only, neat, efficient, and robust against off-line dictionary attacks mounted by …

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Modeling Study Of The Dip-Hump Feature In Bi₂ Sr₂ Cacu₂ O8+Δ Tunneling Spectroscopy, Pierom Romano, Lutfi Ozyuzer, Zikri M. Yusof, Cihan Kurter, John F. Zasadzinski Mar 2006

Modeling Study Of The Dip-Hump Feature In Bi₂ Sr₂ Cacu₂ O8+Δ Tunneling Spectroscopy, Pierom Romano, Lutfi Ozyuzer, Zikri M. Yusof, Cihan Kurter, John F. Zasadzinski

Physics Faculty Research & Creative Works

The tunneling spectra of high-temperature superconductors on Bi2 Sr2 CaCu2 O8+δ (Bi-2212) reproducibly show a high-bias structure in the form of a dip-hump at voltages higher than the gap voltage. Of central concern is whether this feature originates from the normal state background or is intrinsic to the superconducting mechanism. We address this issue by generating a set of model conductance curves-a "normal state" conductance that takes into account effects such as the band structure and a possible pseudogap, and a pure superconducting state conductance. When combined, the result shows that the dip-hump feature present in …

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