Physical Sciences and Mathematics Commons^™

Simple Parallel Statistical Computing In R, Anthony Rossini, Luke Tierney, Na Li

UW Biostatistics Working Paper Series

Theoretically, many modern statistical procedures are trivial to parallelize. However, practical deployment of a parallelized implementation which is robust and reliably runs on different computational cluster configurations and environments is far from trivial. We present a framework for the R statistical computing language that provides a simple yet powerful programming interface to a computational cluster. This interface allows the development of R functions that distribute independent computations across the nodes of the computational cluster. The resulting framework allows statisticians to obtain significant speed-ups for some computations at little additional development cost. The particular implementation can be deployed in heterogeneous computing …

Literate Statistical Practice, Anthony Rossini, Friedrich Leisch

UW Biostatistics Working Paper Series

Literate Statistical Practice (LSP, Rossini, 2001) describes an approach for creating self-documenting statistical results. It applies literate programming (Knuth, 1992) and related techniques in a natural fashion to the practice of statistics. In particular, documentation, specification, and descriptions of results are written concurrently with writing and evaluation of statistical programs. We discuss how and where LSP can be integrated into practice and illustrate this with an example derived from an actual statistical consulting project. The approach is simplified through the use of a comprehensive, open source toolset incorporating Noweb, Emacs Speaks Statistics (ESS), Sweave (Ramsey, 1994; Rossini, et al, 2002; …

On The Local Spectral Properties Of Weighted Shift Operators, Abdellatif Bourhim

Mathematics - All Scholarship

In this paper, we study the local spectral properties for both unilateral and bilateral weighted shift operators.

Ontology-Based Extraction Of Rdf Data From The World Wide Web, Timothy Adam Chartrand

Theses and Dissertations

The simplicity and proliferation of the World Wide Web (WWW) has taken the availability of information to an unprecedented level. The next generation of the Web, the Semantic Web, seeks to make information more usable by machines by introducing a more rigorous structure based on ontologies. One hinderance to the Semantic Web is the lack of existing semantically marked-up data. Until there is a critical mass of Semantic Web data, few people will develop and use Semantic Web applications. This project helps promote the Semantic Web by providing content. We apply existing information-extraction techniques, in particular, the BYU ontologybased data-extraction …

Mitigating Impacts Of Terrestrial Lnvasive Species, Kathleen A. Fagerstone

United States Department of Agriculture Wildlife Services: Staff Publications

Human beings have introduced other species around the world both accidentally and intentionally. Accidental introductions resulted from escape from captivity (monk parakeets [Myiopsitta monachus] in Florida), stowaways (rats [Ranus spp.] and house mice [Mus musculus] worldwide; brown tree snakes [Boiga irregularis] in Guam), or expansion of species' ranges. Intentional introductions occurred for various reasons including: 1) aesthetics (songbirds into Hawaii, grey squirrel [Sciurus carolinensis] into Europe, and European songbirds imported by British colonists into North America, Australia, and New Zealand); 2) economics (nutria [Myocastor coypus] introduced in the …

Ecotones: The Heartbeat Of Huxley, 2003, Winter, Issue 07, Laurel Eddy, Huxley College Of The Environment, Western Washington University

Historical Collection of Huxley Newsletters

No abstract provided.

Magnetic Coupling In Co/Cr2O3/Cro2 "Trilayer" Films, Ruihau Cheng, A. N. Caruso, Lu Yuan, Sy_Hwang Liou, Peter A. Dowben

Peter Dowben Publications

The ferromagnetic coupling between Co and CrO₂ , through an insulator (Cr₂O₃) was characterized by in situ magneto-optic Kerr effect. By evaporating 20–60 Å Co thin films on top of epitaxial CrO₂ films, a Co/Cr₂O₃ /CrO₂ trilayer system can be readily fabricated; this is possible because the native surface layer of CrO₂ is Cr₂O₃ . In situ x-ray photoemission studies show that the Co is oxidized at the interface between Co and Cr₂O₃ , so that the system more resembles Co/CoO/Cr₂O …

Roof Rat Invasion Of An Urban Desert Island, Dale L. Nolte, David Bergman, John Townsend

United States Department of Agriculture Wildlife Services: Staff Publications

Roof rats have invaded the Phoenix metropolitan area. Although the desert surrounding Phoenix is formidacie to roof rats, residential and urban development has probably sufficiently altered habitat to render it suitable for roof rats. Ongoing community and government campaigns are reducing the resources necessary for rat survival and are working to suppress rat populations. Whether these efforts will be adequate to eradicate roof rats from the area is unknown. Rat activity has declined over the past several months. However, it is difficult to assess whether this reduced activity reflects decreased rat numbers or if rats have become less active during …

Pre- And Post-Harvest Movements Of Female Rice-Field Rats In West Japanese Rice Fields, Jens Jacob, Dale L. Nolte, Rudy Hartono

United States Department of Agriculture Wildlife Services: Staff Publications

This study examined changes in the spatial behavior of rice-field rats (Rattus argentiventer) associated with the harvest of lowland irrigated rice. Radio-collared female rice-field rats were tracked before and after harvest in rice fields in West Java, Indonesia. The rice-field rats clearly reacted to the changes in habitat structure caused by the harvest by relocating their home ranges on average 300-400 m to piles of rice straw left on the fields and to unharvested areas. Post-harvest, there was a decrease in home-range size of 67% (0.6 ha pre-harvest: 0.2 ha post-harvest) and a decrease in range span of …

Feasibility Of Non-Lethal Approaches To Protect Riparian Plants From Foraging Beavers In North America, Dale L. Nolte, Mark W. Lutman, David L. Bergman, Wendy M. Arjo, Kelly R. Perry

United States Department of Agriculture Wildlife Services: Staff Publications

Beavers in North America will occupy almost any wetland area containing available forage. Wetland restoration projects often provide the resources necessary for dispersing beavers to create desirable habitats. Their wide distribution and ability to disperse considerable distances almost assure that beavers will establish themselves in new wetlands. Although beavers are a natural and desirable component of a wetland ecosystem, their foraging behaviors can be destructive. Fencing may be a feasible approach to reduce damage to small, targeted areas, and textural repellents may provide some utility to protect established trees. However, these non-lethal approaches will be marginally effective when beaver populations …

Characterization Of Chlorinated Solvent Degradation In A Constructed Wetland, Nathan D. Clemmer

Theses and Dissertations

Widespread chlorinated ethene contamination of aquifers coupled with high costs of current treatment technologies demand innovative remediation solutions. Wetlands, maintaining anaerobic and aerobic zones promoting the complete degradation of chlorinated ethenes such as Tetrachloroethylene (PCE), could be the answer. This thesis characterized the chlorinated solvent contamination levels in three strata of an upward flow constructed wetland. Analysis of samples was accomplished by purge-and-trap gas chromatography. Water quality parameters, Dissolved Oxygen (DO), Oxidation Reduction Potential (ORP), pH, Conductivity, and Temperature, were also measured in monitoring wells with a water monitoring sonde. After removing data outliers caused by short-circuiting flow, PCE concentrations …

Spacecraft Charging At Geosynchronous Altitudes: Current Balance And Critical Temperature In A Non-Maxwellian Plasma, Jose T. Harris

Theses and Dissertations

Spacecraft charging threatens to disable spacecraft components and adversely impact any satellite function. Electrostatic charge, and especially discharge, can hinder the proper operation of, or destroy, spacecraft components, thereby rendering the spacecraft ineffective or inoperative. The level of charging is dependent on the particle energy (speed) distribution. Current spacecraft design and material provide limited protection against the dangers of electrostatic discharge, and active measures such as beam emission are also employed.

Transient Analysis And Applications Of Markov Reward Processes, Jeffrey A. Sipe

Theses and Dissertations

In this thesis, the problem of computing the cumulative distribution function (cdf) of the random time required for a system to first reach a specified reward threshold when the rate at which the reward accrues is controlled by a continuous time stochastic process is considered. This random time is a type of first passage time for the cumulative reward process. The major contribution of this work is a simplified, analytical expression for the Laplace-Stieltjes Transform of the cdf in one dimension rather than two. The result is obtained using two techniques: i) by converting an existing partial differential equation to …

The Virginia Wetlands Report Vol. 18, No. 1, Virginia Institute Of Marine Science

Virginia Wetlands Reports

• The Common Clamworm (Nereis succinea). Rebecca Jo Thomas
• The First Electronic Shoreline Situation Report is Released for the City of Norfolk. Marcia Berman
• An Overview of Permitted Tidal Wetland Impacts for 2002. Karen Duhring
• The Tropical Potato. Pam Mason
• Economics vs. Wetland Protection: How Do Wetland Boards Do It? Thomas Barnard

Radius Of Convergence Of A Power Series, Todor D. Todorov

Mathematics

We derive two simple and memorizable formulas for the radius of convergence of a power series which seem to be appropriate for teaching in an introductory calculus course.

Fusing Information In A 3d Chart-Of-The-Future Display, Roland J. Arsenault, Shep M. Smith Lt, Colin Ware, Larry A. Mayer, Matthew D. Plumlee

Center for Coastal and Ocean Mapping

The Data Visualization Research Lab at the Center for Coastal and Ocean Mapping is investigating how three-dimensional navigational displays can most effectively be constructed. This effort is progressing along multiple paths and is implemented in the GeoNav3D system, a 3D chart-of-the-future research prototype. We present two lines of investigation here. First, we explore how tide, depth, and planning information can be combined (fused) into a single view, in order to give the user a more realistic picture of effective water depths. In the GeoNav3D system, 3D shaded bathymetry, coded for color depth, is used to display navigable areas. As in …

Ab Initio Studies Of Quasi-One-Dimensional Pentagon And Hexagon Ice Nanotubes, Jaeil Bai, C.-R. Su, R. D. Parra, Xiao Cheng Zeng, H. Tanaka, K. Koga, J.-M. Li

Xiao Cheng Zeng Publications

Ab initio plane-wave total-energy calcuation is carried out to study the relative stability of the quasi-one-dimensional (Q1D) pentagon and hexagon ice nanotubes. Electronic structure calculations indicate the two Q1D ice nanotubes have nearly the same band structures and energy bandgap as those of proton-ordered bulk ice I_h . Ab initio molecular-orbital and density-functional theory calculations, as well as three classical potential models of water, are also employed to investigate the relative stability of the pentagon and hexagon water clusters (H₂O) ₃₀, (H₂O) ₆₀ , and (H₂O) ₁₂₀ . Clusters of this kind …

An Analysis Of The Oregon Coastal Exchange Requirement, Jordan Vinograd

Center for Lakes and Reservoirs Publications and Presentations

This report was generated at the request of the Oregon Ballast Water Task Force to address the issue of coastal shipping and exchange requirements along the West Coast of North America. The Oregon Ballast Water Management Program was established by SB 895 during the 2001 legislative session to address the introduction of aquatic nuisance species when ballast water is discharged from ships. There are several levels of ballast water management as established by the National Invasive Species Act of 1996. However, the national program does not address the issues of interstate vessel voyages. Therefore, California, Washington and Oregon have establishedm …

Whaling As Science, Phillip J. Clapham, Per Berggren, Simon Childerhouse, Nancy A. Friday, Toshio Kasuya, Laurence Kell, Karl-Hermann Kock, Silvia Manzanilla-Naim, Giuseppe Notabartolo Di Sciara, William F. Perrin, Andrew J. Read, Randall R. Reeves, Emer Rogan, Lorenzo Rojas-Bracho, Tim D. Smith, Michael Stachowitsch, Barbara L. Taylor, Deborah Thiele, Paul R. Wade, Robert L. Brownell Jr.

United States Department of Commerce: Staff Publications

In an open letter published last year in the New York Times, 21 distinguished scientists (including three Nobel laureates) criticized Japan's program of scientific research whaling, noting its poor design and unjustified reliance upon lethal sampling. In a recent Forum article in BioScience, Aron, Burke, and Freeman (2002) castigate the letter's signers and accuse them of meddling in political issues without sufficient knowledge of the science involved in those issues.

The Development Of Relationships Between Constituent Concentrations And Generic Hydrological Variables, Carmen T. Agouridis, Dwayne R. Edwards

Biosystems and Agricultural Engineering Faculty Publications

The collection and analysis of samples from storm events constitutes a large portion of the effort associated with water quality research. Estimating concentrations or loads from these events is often difficult. The equipment necessary to analyze the samples and the required laboratory resources are typically significant expenses incurred by the researcher. One potential method to reduce these costs is through the development of generic relationships between concentrations and easily measured variables such as dimensionless flow rate or time. The benefits recognized from such an effort include a reduction in the number of required samples, resulting in a reduction in cost. …

Pc–Based Data Acquisition For A Solid Substrate Cultivation Deep Bed Reactor, Mari S. Chinn, Sue E. Nokes, Richard S. Gates

Biosystems and Agricultural Engineering Faculty Publications

This work describes an instrumentation and data acquisition system designed for a deep bed reactor used to cultivate Trichoderma longibrachiatum on wheat bran. The system allowed on–line measurements of substrate temperature, oxygen concentration within the reactor headspace, relative humidity and temperature of the inlet air, and inlet airflow rates while maintaining aseptic conditions and without disturbing the cultivation process. An error analysis for the instrumentation and data acquisition equipment was completed and provided insight into the reliability of the sensor readings. The collected data provided quantitative information about the reactor system dynamics which can be used to evaluate and apply …

Increasing Involvement In And Awareness Of Coastal Zone Management In New Jersey, Urban Harbors Institute, University Of Massachusetts Boston

Urban Harbors Institute Publications

A discussion paper prepared as part of a series of focus groups on the topic of the Increasing Involvement in and Awareness of Coastal Zone Management in New Jersey.

Among the requirements of the federal Coastal Zone Management Act (CZMA) for state coastal management programs are procedures for public participation and intergovernmental coordination in program development and implementation.

The CZMA was one of a number of environmental statutes passed by Congress in the early 1970s that made public participation a cornerstone of the program. Most government programs have since adopted this philosophy, and experience over the past several decades confirms …

Pareto Optimal Allocations In Nonconvex Models Of Welfare Economics, Boris S. Mordukhovich

Mathematics Research Reports

The paper is devoted to applications of modern variational analysis to the study of Pareto (as well as weak and strong Pareto) optimal allocations in nonconvex models of welfare economics with infinite-dimensional commodity spaces. Our basic tool is the extremal principle of variational analysis that provides necessary conditions for set extremality and may be viewed as a variational extension of the classical convex separation principle to the case of nonconvex sets. In this way we obtain new versions of the generalized second welfare theorem for nonconvex economies in terms of appropriate concepts of normal cones.

Bayesian Shrinkage Estimation Of The Relative Abundance Of Mrna Transcripts Using Sage, Jeffrey S. Morris, Keith A. Baggerly, Kevin R. Coombes

Jeffrey S. Morris

Serial analysis of gene expression (SAGE) is a technology for quantifying gene expression in biological tissue that yields count data that can be modeled by a multinomial distribution with two characteristics: skewness in the relative frequencies and small sample size relative to the dimension. As a result of these characteristics, a given SAGE sample may fail to capture a large number of expressed mRNA species present in the tissue. Empirical estimators of mRNA species’ relative abundance effectively ignore these missing species, and as a result tend to overestimate the abundance of the scarce observed species comprising a vast majority of …

Future Climate Analysis -- 10,000 Years To 1,000,000 Years After Present, Saxon E. Sharpe, Dwight Hoxie, Amy J. Smiecinski

Publications (YM)

The purpose of this report is to provide quantified estimates of temperature and precipitation and estimate the timing of climate states in the Yucca Mountain, Nevada, area for the period from 10,000 to 1,000,000 years beyond the present. Primary tasks are limited to: 1) selecting modern analog climate stations for three different magnitude glacial stages; and, 2) determining the timing of future climate states using orbital parameter data and Devils Hole and Owens Lake records. These estimates are intended to be used as input to models of the infiltration process to assess the performance of the natural and engineered systems …

The Solvent Boundary Potential: A New Approach For Computer Simulation Of Large Systems, Valentin Gogonea

Chemistry Faculty Publications

The paper presents the theoretical framework for the development of a new solvent boundary method for computer simulations and its possible application to the simulation of nitric oxide synthase. Different approaches for the construction of a solvent boundary potential are reviewed and their strengths and weaknesses are discussed. A new solvent boundary potential is proposed which combines the mean field force approximation with the Green's function approach for treating long-range electrostatic interactions, and introduces a novel strategy to treat electrostriction effects due to ions crossing the solvent boundary. Finally, a series of computational tests are devised in order to assess …

Creating And Modifying Dynamic Animation Sequences Using The Tgt_Toolkit, Ross Gore

Department of Math & Statistics Technical Report Series

Creating and modifying the dynamic animation sequences within the TGT_Toolkit is not for the faint of heart. This report contains advice, guidelines and refers to an example of how I went about constructing the dynamic animation sequences within the Linked Lists Tutorial. I have identified three major areas of that seem to be common to all dynamic animation sequences, but distinct from simply extending TGT_Slide as most other slides do; these areas are: dynamically creating animation configurations, providing "undo" and slide saving functionality and sequencing saved slides once they are properly configured. In these areas "slide saving" and "saved slides" …

Cio Lateral Influence Behaviors: Gaining Peers' Commitment To Strategic Information Systems, Harvey Enns, Sid L. Huff, Christopher A. Higgins

MIS/OM/DS Faculty Publications

In order to develop and bring to fruition strategic information systems (SIS) projects, chief information officers (CIOs) must be able to effectively influence their peers. This research examines the relationship between CIO influence behaviors and the successfulness of influence outcomes, utilizing a revised model initially developed by Yukl (1994). Focused interviews were first conducted with CIOs and their peers to gain insights into the phenomenon. A survey instrument was then developed and distributed to a sample of CIO and peer executive pairs to gather data with which to test a research model. A total of 69 pairs of surveys were …

Marine Information Objects (Mio) And Ecdis: Concept And Practice, Lee Alexander

Center for Coastal and Ocean Mapping

Marine Information Objects (MIOs) consist of chart- and navigation-related information that supplement the minimum information required by ECDIS to ensure safety of navigation at sea. As related to the use of Electronic Navigational Chart (ENC) data, MIOs are additional, non-mandatory information not already covered by existing IMO, IHO, or IEC standards. Such information includes ice coverage, tide/water level, current flow, meteorological, oceanographic, and marine habitats. A Harmonization Group on MIOs (HGMIO) has been established between IHO and IEC to recommend additional data and display specifications that may be incorporated into future editions of IHO and IEC standards. This paper discusses …

Universal Multimedia Experiences For Tomorrow, F. Pereira, I. Burnett

Faculty of Informatics - Papers (Archive)

The previous decade has seen a variety of trends and developments in the area of communications and thus multimedia access. While individual, isolated developments produced small advances on the status quo, their combination and cross-fertilization resulted in today's complex but exciting landscape. In particular, we are beginning to see delivery of all types of data for all types of users in all types of conditions. This article discusses the current status of universal multimedia access (UMA) technologies and investigates future directions in this area. Key developments and trends from the last few years have set the scene for ubiquitous multimedia …