Physical Sciences and Mathematics Commons^™

Homogeneous Markov Processes For Breast Cancer Analysis, Ricardo Ocaña-Rilola, Emilio Sanchez-Cantalejo, Carmen Martinez-Garcia

Journal of Modern Applied Statistical Methods

Sometimes, the introduction of covariates in stochastic processes is required to study their effect on disease history events. However these types of models increase the complexity of analysis, even for simpler processes, and standard software to analyse stochastic processes is limited. In this paper, a method for fitting homogeneous Markov models with covariates is proposed for analysing breast cancer data. Specific software for this purpose has been implemented.

Spheromak Merging And Field Reversed Configuration Formation At The Swarthmore Spheromak Experiment, C. D. Cothran, Abram Lockhart Falk , '03, Matthew J. Landreman , '03, Michael R. Brown, M. J. Schaffer

Physics & Astronomy Faculty Works

The initial results of coaxial co- and counter-helicity spheromak merging studies at the Swarthmore Spheromak Experiment (SSX) [M. R. Brown, Phys. Plasmas 6, 1717 (1999)] are reported. In its new configuration, SSX is optimized to study field reversed configuration (FRC) formation and stability by counter-helicity spheromak merging. A pair of midplane coils magnetically restricts the merging process to determine how the stability of the resulting magnetic configuration depends upon the quantity of toroidal flux remaining from the initial spheromaks. The diagnostic set at SSX, featuring the capability of measuring up to 600 magnetic field components at 800 ns time resolution, …

Modeling Habitat Quality For American Martens In Western Newfoundland, Canada, William A. Adair

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The "Den Mother" marten habitat quality models were created to provide insight into American marten habitat selection behavior and to promote the recovery of the Newfoundland marten (Martes americana atrata) population. Although these objectives are typical of most wildlife habitat modeling projects, the marten's idiosyncratic habitat ecology and apparently intractable conflicts associated with timber harvesting motivated a unique, process-oriented approach to appraising landscapes. The Den Mother models used optimal decision-making principles to synthesize critical resources (den sites and foraging opportunities) and constraints (adverse thermal situations and exposure to predations) into a single hierarchical framework. The resulting spatially explicit, …

From The Rim To The River: The Geomorphology Of Debris Flows In The Green River Canyons Of Dinosaur National Monument, Colorado And Utah, Isaac J. Larsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Green River canyons of the eastern Uinta Mountains have experienced a 5-year period of high debris flow activity. Catchment factors were studied in watersheds and on debris fans with recent debris flows, leading to the development of a conceptual framework of the hillslope and debris flow processes that deliver sediment to the Green River. Two recent fan deposits were monitored to determine the magnitude and processes of reworking that occur during mainstem floods of varying magnitude.

The dominant debris flow initiation mechanism, termed the firehose effect, occurs when overland flow generated on bedrock slopes cascades down steep cliffs and …

Characteristics, Evolution, And Lateral Variation Of Lower Cretaceous Supradetachment Basins In The Daqing Shan, Inner Mongolia, China, Adrian K. Berry

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Lower Cretaceous basins associated with the Hohhot detachment in the Daqing Shan of Inner Mongolia, China, allow us to better understand the tectonic evolution of extensional basins formed in association with detachment faulting and metamorphic core complex formation. The six basins, informally named N1, N2, S1, S2, S3, and S4, are located in different structural settings, or depozones, throughout the detachment-metamorphic core complex setting, and although all basins are consistent with previously proposed models for supradetachment basin sedimentation, second-order variability in sedimentary style is exerted by these distinct structural settings. The basins are composed of coarse, predominantly footwall derived, conglomerate …

Geology Of The Deseret Peak East 7.5' Quadrangle, Tooele County, Utah, And Impacts For Hydrology Of The Region, Torrey J. Copfer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Detailed geologic mapping of the Deseret Peak East 7.5' Quadrangle yields new interpretations regarding the stratigraphy of the Oquirrh Basin, fault and fold geometry, and structural evolution of the region. The Stansbury Range consists of the north-south-trending Deseret anticline. Basal Mississippian units rest unconformably on Cambrian beds in the central part of the range. Paleozoic uplift, Mesozoic contraction, and Cenozoic extension have created a series of broad folds, large thrust faults, and several normal faults.

The area is dominated by bedrock springs, with the presence of abundant and thick Quaternary deposits unrelated to Pleistocene glaciation, burying drainages, and mantling hillslopes. …

Quaternary Geology And Landscape Evolution Of Eastern Grand Canyon, Arizona, Matt D. Anders

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Tectonics and drainage evolution are controlling overall landscape incision in eastern Grand Canyon. Superimposed on downcutting are dynamic responses of hillslopes, tributary streams, and the Colorado River to glacial-interglacial climate cycles. Five tributary stream fill terraces have been identified, and luminescence dating indicates aggradation was occurring 50- 34 ka {S3), 12-7 ka (S2), and 5-3.5 ka (S1). Seven Colorado River fill terraces have been identified, and luminescence and U-series dating indicate deposition was occurring 343-322 ka (M5), 151-118 ka (M4), and 71-64 ka (M3).

Aggradation by the Colorado River in eastern Grand Canyon begins during glacial advances and continues into …

Validation Of A Radiometric Normalization Procedure For Satellite-Derived Imagery Within A Change Detection Framework, Karin E. Callahan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Detecting changes in land cover through time using remotely sensed imagery is a powerful application that has seen increased use as imagery has become more widely available and inexpensive. Before a time series of remotely sensed imagery can be used for change detection, images must first be standardized for effects outside of real surface change. This thesis established a validation protocol to evaluate the effectiveness of an automated technique for normalizing temporally separate but spatially coincident imagery. Using the concept of pseudo-invariant features between master-slave image pairs, spatially coincident dark and bright points are identified from images and a regression …

Determining The Factors That Control Respiration And Carbon Use Efficiency In Crop Plants, Jonathan M. Frantz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In the literature on plant respiration, there are two viewpoints concerning the source of respiratory control: supply (photosynthate availability) or demand (temperature dependent) limitations. While different studies indicate the primary dependency for respiration is either the supply or demand side, the two paradigms cannot both be true. The relative importance of each paradigm may depend on a number of factors including period of time during which respiration is measured, phase of plant development, environmental conditions, and species.

Studies were performed using continuous CO₂ gas-exchange instrumentation to monitor short- and long-term changes in whole canopies of lettuce, tomato, soybean, and …

Breeding Bird Communities Of Major Mainland Rivers Of Southeastern Alaska, Jim A. Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Because of the scarcity of information for bird communities at the major mainland rivers of southeastern Alaska, the main objective of this study was to provide baseline information including distribution, status, and habitat associations of breeding birds.

I conducted a meta-analysis of all known reports (including the current study) conducted at major mainland rivers during the breeding season. I described bird species composition, distribution, abundance estimates, status, habitat associations, and guild membership for all birds recorded at 11 major mainland rivers. Based on incidental observations, 170 species were recorded by all studies. Of these, 134 species were known or suspected …

The Middle Cambrian Wheeler Formation: Sequence Stratigraphy And Geochemistry Across A Ramp-To-Basin Transition, Elizabeth S. Langenburg

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Middle Cambrian Wheeler Formation is interpreted as having been deposited in the shallow ramp and deeper basin environments of the House Range embayment (HRE), presumably, during a single third-order sequence. In the Drum Mountains, the Wheeler Formation (295 m thick) is dominated by proximal and distal ramp deposits; at Marjum Pass, the Wheeler Formation (190m thick) is dominated by basinal shale deposits. The Wheeler Formation contains only one biozone marker; the first appearance of Ptyhagnostus atavus. Lack of other chronostratigraphic markers and distinctive stratal patterns in the basinal facies makes correlation along this ramp-to-basin transect difficult. Therefore, carbon-isotope …

Oxygen Delignification Kinetics And Selectivity Improvement, Steven M. Violette

Electronic Theses and Dissertations

Pulp strength loss during oxygen delignification is caused by cellulose chain cleavage resulting fiom attack by oxygen-based radicals generated through reactions with lignin. The objective of this research was to improve the lignin-to-cellulose selectivity during oxygen delignification by using radical-scavenging polymeric additives that adsorb on the cellulose surfaces where protection fiom radicals is needed. Among the polymers evaluated were starch, carboxymethyl-cellulose, galactomannan, xylan, and glucomannan. Oxygen delignification experiments were conducted on Northeast softwood Kraft pulps at different temperatures, sodium hydroxide charges, reaction times, and pretreatments. The effect of polymer additives on the selectivity and kinetics was studied. Polymer adsorption on …

Characterisation Of Polymer-Modified Electrodes, Karl Crowley

Doctoral

In this work, two contrasting polymer-modified electrodes are investigated. Electroanalysis of lead in aqueous solutions was performed with an electrode coated with Nafion and the redox behaviour of the electronically conducting polymer, polypyrrole, was characterised. In the first study, a glassy carbon electrode coated with Nafion was used in the determination of lead through anodic stripping voltammetry (ASV). Initially the work consisted of optimising the preparation of the electrode and the experimental conditions resulting in a reproducible Nafion-modified electrode (NME) with a lifetime of several weeks. Two different stripping techniques were examined. High frequency square wave ASV was found to …

The Probe, Issue 228 – May/June 2003

The Probe: Newsletter of the National Animal Damage Control Association

• The Urban Coyote -- Dallas Virchow
• Since the distribution of some species of vampire bats extends to northern Mexico, do these bats ever enter the U.S. ?
• The first of many BMPs for trapping is now on-line. Below you will find a link that provides the new Best Management Practices (BMPs) for trapping coyotes in the eastern United States: http://www.furbearermgmt.org/03ecbmp.pdf
• Human-Wildlife Conflicts in China -- Alex E Mettler, Berryman Institute, Utah State University
• An Arizona DPS officer found this animal dead along an interstate highway in Arizona. The officer thought it looked like a rat, …

Applications Of List Decoding To Tracing Traitors, Alice Silverberg, Jessica Staddon, Judy L. Walker

Department of Mathematics: Faculty Publications

We apply results from algebraic coding theory to solve problems in cryptography, by using recent results on list decoding of error-correcting codes to efficiently find traitors who collude to create pirates. We produce schemes for which the TA (traceability) traitor tracing algorithm is very fast. We compare the TA and IPP (identifiable parent property) traitor tracing algorithms, and give evidence that when using an algebraic structure, the ability to trace traitors with the IPP algorithm implies the ability to trace with the TA algorithm. We also demonstrate that list decoding techniques can be used to find all possible pirate coalitions. …

Ρ-Queries: Enabling Querying For Semantic Associations On The Semantic Web, Kemafor Anyanwu, Amit P. Sheth

Kno.e.sis Publications

This paper presents the notion of Semantic Associations as complex relationships between resource entities. These relationships capture both a connectivity of entities as well as similarity of entities based on a specific notion of similarity called ρ-isomorphism. It formalizes these notions for the RDF data model, by introducing a notion of a Property Sequence as a type. In the context of a graph model such as that for RDF, Semantic Associations amount to specific certain graph signatures. Specifically, they refer to sequences (i.e. directed paths) here called Property Sequences, between entities, networks of Property Sequences (i.e. undirected paths), or subgraphs …

The Use Of Acoustics To Resolve Nightly Excursions Of Hyperbenthos, Heather U. Abello

Electronic Theses and Dissertations

Acoustic analysis of die1 vertical migration in the Darnariscotta River estuary, Maine, showed a fairly regular nightly increase in biovolume (mm3 m'3) of organisms in the water column, presumed to be due to emergence, the entry of hyperbenthic organisms into the water column. Timing of these events was significantly correlated with time of sunset and time of sunrise for more than 50% of the dates where emergence and re-entry could be identified, between June and October 2002. Emergence traps indicate that the mysid shrimp, Neomysis americana, is the predominant migrator. Daily fluctuations in irradiance influence the timing of emergence fiom …

Ga Vacancies As Dominant Intrinsic Acceptors In Gan Grown By Hydride Vapor Phase Epitaxy, J. Oila, J. Kivioja, V. Ranki, K. Saarinen, David C. Look, Richard J. Molnar, S. S. Park, S. K. Lee, J. Y. Han

Physics Faculty Publications

Positron annihilation measurements show that negative Ga vacancies are the dominant acceptors in n-type gallium nitride grown by hydride vapor phase epitaxy. The concentration of Ga vacancies decreases, from more than 10¹⁹ to below 10¹⁶ cm⁻³, as the distance from the interface region increases from 1 to 300 μm. These concentrations are the same as the total acceptor densities determined in Hall experiments. The depth profile of O is similar to that of V_Ga, suggesting that the Ga vacancies are complexed with the oxygen impurities.

Genescene: Biomedical Text And Data Mining, Gondy Leroy, Hsinchun Chen, Jesse D. Martinez, Shauna Eggers, Ryan R. Falsey, Kerri L. Kislin, Zan Huang, Jiexun Li, Jie Xu, Daniel M. Mcdonald, Gavin Ng

CGU Faculty Publications and Research

To access the content of digital texts efficiently, it is necessary to provide more sophisticated access than keyword based searching. GeneScene provides biomedical researchers with research findings and background relations automatically extracted from text and experimental data. These provide a more detailed overview of the information available. The extracted relations were evaluated by qualified researchers and are precise. A qualitative ongoing evaluation of the current online interface indicates that this method to search the literature is more useful and efficient than keyword based searching.

A Self-Organizing Map For Adaptive Processing Of Structured Data, Markus Hagenbuchner, A. Sperduti, Ah Chung Tsoi

Faculty of Informatics - Papers (Archive)

Recent developments in the area of neural networks produced models capable of dealing with structured data. Here, we propose the first fully unsupervised model, namely an extension of traditional self-organizing maps (SOMs), for the processing of labeled directed acyclic graphs (DAGs). The extension is obtained by using the unfolding procedure adopted in recurrent and recursive neural networks, with the replicated neurons in the unfolded network comprising of a full SOM. This approach enables the discovery of similarities among objects including vectors consisting of numerical data. The capabilities of the model are analyzed in detail by utilizing a relatively large data …

Scope For Activity, Specific Dynamic Action And Growth In Early Juvenile Stages Of Atlantic Cod, Gadus Morhua, Sorren Lund Hansen

Electronic Theses and Dissertations

Growth rates of early life stages of Atlantic cod (Gadus morhua) are very high, but decline, as the fish grow larger. Little is know about the physiological processes that facilitate and regulate this growth pattern. In this study, feeding and swimming metabolism were measured in individual juvenile Atlantic cod (Gadus morhua) in order to investigate how energy are allocated to swimming and growth in fast growing stages of fishes. Metabolic rates were measured by the means of oxygen consumption using two "Brett-type" respirometers. The metabolic measurements were repeated several times in individual juvenile Atlantic cod with a wet body mass …

The Numerical Design Of A Parallel Plate Flow Chamber For Investigation Of Endothelial Cell Response To Shear Stress, Bong Jae Chung, A. M. Robertson, D. G. Peters

Department of Applied Mathematics and Statistics Faculty Scholarship and Creative Works

Parallel plate chambers are frequently used to examine the response of biological cells to a constant wall shear stress. However, the stress can vary more than 80% across the chamber due to end effects. Earlier estimates of the magnitude of this inhomogeneity used boundary layer theory and experiments. Here, the full equations for steady, three-dimensional flow in a novel parallel plate device were solved numerically and used to identify an active test region where the shear stress is within 5% of a constant value. Endothelial cells can be confined to this region to assure a nearly uniform shear stress exposure.

Psf Measurements On Back-Illuminated Ccds, Ralf Widenhorn, Alexander Weber, Morley M. Blouke, Albert J. Bae, Erik Bodegom

Physics Faculty Publications and Presentations

The spatial resolution of an optical device is generally characterized by either the Point Spread Function (PSF) or the Modulation Transfer Function (MTF). To directly obtain the PSF one needs to measure the response of an optical system to a point light source. We present data that show the response of a back-illuminated CCD to light emitted from a sub-micron diameter glass fiber tip. The potential well in back-illuminated CCD"s does not reach all the way to the back surface. Hence, light that is absorbed in the field-free region generates electrons that can diffuse into other pixels. We analyzed the …

Persistence And Prevalence In The Mobility Of Dartmouth Wireless Network Users, Clara Lee

Dartmouth College Undergraduate Theses

Wireless local-area networks (WLANs) are increasing in popularity. As more people use WLANs it is important to understand how these users behave. We analyzed data collected over three months of 2002 to measure the persistence and prevalence of users of the Dartmouth wireless network.

We found that most of the users of Dartmouth's network have short association times and a high rate of mobility. This observation fits with the predominantly student population of Dartmouth College, because students do not have a fixed workplace and are moving to and from classes all day.

Trusted S/Mime Gateways, Mindy J. Pereira

Dartmouth College Undergraduate Theses

The utility of Web-based email clients is clear: a user is able to access their email account from any computer anywhere at any time. However, this option is unavailable to users whose security depends on their key pair being stored either on their local computer or in their browser. Our implementation seeks to solve two problems with secure email services. The first that of mobility: users must have access to their key pairs in order to perform the necessary cryptographic operations. The second is one of transition: initially, users would not want to give up their regular email clients. Keeping …

An Active Learning Approach To Efficiently Ranking Retrieval Engines, Lisa A. Torrey

Dartmouth College Undergraduate Theses

Evaluating retrieval systems, such as those submitted to the annual TREC competition, usually requires a large number of documents to be read and judged for relevance to query topics. Test collections are far too big to be exhaustively judged, so only a subset of documents is selected to form the judgment ``pool.'' The selection method that TREC uses produces pools that are still quite large. Research has indicated that it is possible to rank the retrieval systems correctly using substantially smaller pools. This paper introduces an active learning algorithm whose goal is to reach the correct rankings using the smallest …

Sustainability Issues For Agriculture In Western Australia, Anne Bennett, Ross Kingwell, Ross George

Agriculture reports

This paper describes briefly the main challenges to the sustainability of agriculture in Western Australia and outlines some means of responding the the challenges: market-based approaches; agricultural and environmental research and development; accelerated adjustment; and global and national policy initiatives. Challenges include: land resource quality (salinity, soil acidity), biodiversity, greenhouse gas emissions, climate change, water availability, food safety, and pests and diseases.

Kiosk Engine: A Platform Independent Solution For Multimedia Kiosks, Manish Satish Shah

Theses and Dissertations

In today's fast paced life saving time is the first priority of every business organization and presenting information visually is a highly desirable and the easiest way to impressively communicate to people. For that purpose, there are interactive devices called kiosks, which display multimedia data on a display and are quite often attached to other input/output hardware like keyboard, mouse, printer, etc. Most of today's kiosks are custom made and are designed for specific set of target platform. The task of creating a kiosk can turn out to be difficult and fairly time consuming. The aim of this thesis is …

Planning Your Way To A More Usable Web Site, Pamela Gore, Sandra Hirsh

Faculty Publications

Planning for long-term periodic usability assessment is therefore as important as adding regularly fresh content and tracking usage. Fortunately, usability assessments need not be time consuming or expensive, unless your site is large and complex and you want to test it thoroughly each time. In a practical sense, usability assessment can reveal problems in the design, navigation, layout, or labeling that prevent users from finding what they need quickly. After analyzing your environment and setting the stage for ongoing usability assessment, it is time to develop the usability assessment plan, which will serve as the blueprint for usability assessment activities …

Surface Interactions Of Mercury On Gold Foil Electrodes In Electrodeposition And Stripping And ; An Investigation Of Free Thiolate Ions From Metal-Thiolate Chalcogenides, Charles Martin Watson

Electronic Theses and Dissertations

Mercury, a highly toxic metal, whose environmental concentration magnifies with ascension of the food chain, is monitored in our waters, food and air. Monitoring mercury is generally done by sample collection, transport to the laboratory; followed by: digestion of the sample, separation of the mercury and detection of the mercury: mostly by cold vapor atomic absorption or, cold vapor atomic fluorescence. These monitoring methods, preclude, routine, in-the-field mercury determination. New analytical techniques have been proposed for in the field determination of mercury. They consist of mercury adsorption onto a sensor or electrode and measuring how much is there either as …