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Super-Resolution Via Image Recapture And Bayesian Effect Modeling, Neil B. Toronto Mar 2009

Super-Resolution Via Image Recapture And Bayesian Effect Modeling, Neil B. Toronto

Theses and Dissertations

The goal of super-resolution is to increase not only the size of an image, but also its apparent resolution, making the result more plausible to human viewers. Many super-resolution methods do well at modest magnification factors, but even the best suffer from boundary and gradient artifacts at high magnification factors. This thesis presents Bayesian edge inference (BEI), a novel method grounded in Bayesian inference that does not suffer from these artifacts and remains competitive in published objective quality measures. BEI works by modeling the image capture process explicitly, including any downsampling, and modeling a fictional recapture process, which together allow …

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Uncovering Transformative Experiences: A Case Study Of The Transformations Made By One Teacher In A Mathematics Professional Development Program, Rachelle Myler Orsak Mar 2009

Uncovering Transformative Experiences: A Case Study Of The Transformations Made By One Teacher In A Mathematics Professional Development Program, Rachelle Myler Orsak

Theses and Dissertations

Effective professional development is vital for improving mathematics teaching (National Council of Teachers of Mathematics [NCTM], 2007), so studying effective professional development programs is important to the field of mathematics education. This case study presents findings on one teacher, Rebecca, and her experiences in a five-semester mathematics professional development for elementary teachers. The participants in this professional development engaged in collaborative problem solving of challenging mathematical tasks over extended periods of time. I used qualitative research methods based on grounded theory methodology (Charmaz, 2006) to analyze Rebecca's entrance and exit surveys, video data of Rebecca's individual interviews, and video data …

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Variable Uplift From Quaternary Folding Along The Northern Coast Of East Timor, Based On U-Series Age Determinations Of Coral Terraces, Nicole L. Cox Mar 2009

Variable Uplift From Quaternary Folding Along The Northern Coast Of East Timor, Based On U-Series Age Determinations Of Coral Terraces, Nicole L. Cox

Theses and Dissertations

Surveys of emergent terraces and U-series ages for ten sites along the coast of East Timor provide estimates of late Quaternary differential vertical strain in the most mature region of the Banda Arc-continent collision complex. Over a distance of ~180 km vertical displacement rates vary between 0.0 and 1.6 meters per 1000 years for the last 150,000 years. Two models of terrace formation (constructional and erosional) are applied to interpret terrace ages from coral ages and to estimate uplift rates. The highest uplift rates are from three sites over a distance of 15 km along the coast. Uplift rates were …

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Near-Optimal Antenna Design For Multiple Antenna Systems, Daniel N. Evans Mar 2009

Near-Optimal Antenna Design For Multiple Antenna Systems, Daniel N. Evans

Theses and Dissertations

Multiple-input-multiple-output (MIMO) wireless systems use multiple antenna elements at the transmitter and receiver to offer improved spectral efficiency over traditional single antenna systems. In these systems, properties of the transmit and receive antenna arrays play a key role in determining the overall performance of the system. This thesis derives an upper bound on ergodic (average) channel capacity which formally links good antenna diversity performance with good ergodic capacity. As a result of this derivation, antenna arrays with good ergodic capacity performance are designed in this thesis by designing antenna arrays with near-optimal diversity gain. Several approaches are developed to design …

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Characterizing The Statistical Properties And Global Distribution Of Dansgaard-Oeschger Events, Andrea Michelle Thomas Mar 2009

Characterizing The Statistical Properties And Global Distribution Of Dansgaard-Oeschger Events, Andrea Michelle Thomas

Theses and Dissertations

Ice core records from Greenland have shown times of rapid warming during the most recent glacial period, called Dansgaard-Oeschger (D-O) events. D-O events are important to our understanding of both past climate systems and modern climate volatility. In this paper, we present new approaches for statistically evaluating the existence of cyclicity in D-O events and the possible lagged correlation between the Greenland and Antarctica temperature records. Specifically, we consider permutation testing and bootstrapping methodologies for assessing the cyclicity of D-O events and the correlation between the Greenland and Antarctica records. We find that there is not enough evidence to conclude …

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A Dynamic Attribute-Based Data Filtering And Recovery Scheme For Web Information Processing, Amit Ahuja, Yiu-Kai D. Ng Mar 2009

A Dynamic Attribute-Based Data Filtering And Recovery Scheme For Web Information Processing, Amit Ahuja, Yiu-Kai D. Ng

Faculty Publications

Web data being transmitted over a network channel on the Internet with excessive amount of data causes data processing problems, which include selectively choosing useful information to be retained for various data applications. In this paper, we present an approach for filtering less-informative attribute data from a source Website. A scheme for filtering attributes, instead of tuples (records), from a Website becomes imperative, since filtering a complete tuple would lead to filtering some informative, as well as less-informative, attribute data in the tuple. Since filtered data at the source Website may be of interest to the user at the destination …

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Stochastic Spatio-Temporal Uncertainty In Gis-Based Water Quality Modeling Of The Land Water Interface, Ahmad Mohamad Salah Feb 2009

Stochastic Spatio-Temporal Uncertainty In Gis-Based Water Quality Modeling Of The Land Water Interface, Ahmad Mohamad Salah

Theses and Dissertations

Integrated water resources management has been used for decades in various formats. The limited resources and the ever growing population keep imposing pressure on decision makers to better-, and reliably, manage the available waters. On the other hand, the continuous development in computing and modeling power has helped modelers and decision makers considerably. To use these models, assumptions have to be made to fill in the gaps of missing data and to approximate the current conditions. The type and amount of information available can also be used to help select the best model from the currently available models. Advances in …

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Polymer Microfluidic Devices For Bioanalysis, Xuefei Sun Feb 2009

Polymer Microfluidic Devices For Bioanalysis, Xuefei Sun

Theses and Dissertations

Polymeric microchips have received increasing attention in chemical analysis because polymers have attractive properties, such as low cost, ease of fabrication, biocompatibility and high flexibility. However, commercial polymers usually exhibit analyte adsorption on their surfaces, which can interfere with microfluidic transport in, for example, chemical separations such as chromatography or electrophoresis. Usually, surface modification is required to eliminate this problem. To perform stable and durable surface modification, a new polymer, poly(methyl methacrylate-co-glycidyl methacrylate) (PGMAMMA) was prepared for microchip fabrication, which provides epoxy groups on the surface. Whole surface atom transfer radical polymerization (ATRP) and in-channel ATRP approaches were employed to …

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A New Model For Aqueous Electrolyte Solutions Near The Critical Point Of Water Incorporating Aqueous Reaction Equilibria, Craig J. Peterson Feb 2009

A New Model For Aqueous Electrolyte Solutions Near The Critical Point Of Water Incorporating Aqueous Reaction Equilibria, Craig J. Peterson

Theses and Dissertations

Aqueous electrolyte solutions at temperature and pressure conditions near the critical point of water are difficult to describe using traditional equations of state based upon the excess Gibbs energy. Models based upon the residual Helmholtz energy have proven more effective. Anderko and Pitzer1 developed a residual Helmholtz energy model (AP) for aqueous electrolyte solutions in which the electrolyte is assumed to be fully associated. The model has been effectively used in describing densities and vapor-liquid equilibria for simple electrolyte systems. The model is less effective for describing enthalpic properties such as heats of dilution. Oscarson and coworkers2, 3 modified the …

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A Unified Approach To Gpu-Accelerated Aerial Video Enhancement Techniques, Stephen Thayn Cluff Feb 2009

A Unified Approach To Gpu-Accelerated Aerial Video Enhancement Techniques, Stephen Thayn Cluff

Theses and Dissertations

Video from aerial surveillance can provide a rich source of data for analysts. From the time-critical perspective of wilderness search and rescue operations, information extracted from aerial videos can mean the difference between a successful search and an unsuccessful search. When using low-cost, payload-limited mini-UAVs, as opposed to more expensive platforms, several challenges arise, including jittery video, narrow fields of view, low resolution, and limited time on screen for key features. These challenges make it difficult for analysts to extract key information in a timely manner. Traditional approaches may address some of these issues, but no existing system effectively addresses …

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Survival Analysis With High-Dimensional Covariates: An Application In Microarray Studies, David Engler, Yi Li Feb 2009

Survival Analysis With High-Dimensional Covariates: An Application In Microarray Studies, David Engler, Yi Li

Faculty Publications

Use of microarray technology often leads to high-dimensional and low-sample size (HDLSS) data settings. A variety of approaches have been proposed for variable selection in this context. However, only a small number of these have been adapted for time-to-event data where censoring is present. Among standard variable selection methods shown both to have good predictive accuracy and to be computationally efficient is the elastic net penalization approach. In this paper, adaptations of the elastic net approach are presented for variable selection both under the Cox proportional hazards model and under an accelerated failure time (AFT) model. Assessment of the two …

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Decentralized Estimation Using Information Consensus Filters With A Multi-Static Uav Radar Tracking System, David W. Casbeer Feb 2009

Decentralized Estimation Using Information Consensus Filters With A Multi-Static Uav Radar Tracking System, David W. Casbeer

Theses and Dissertations

This dissertation lays out a multi-static radar system with mobile receivers. The transmitter is at a known location emitting a radar signal that bounces off a target. The echo is received by a team of UAVs that are capable of estimating both time-delay and Doppler from the received signal. Several methods for controlling the movement of mobile sensor platforms are presented to improve target tracking performance. Two optimization criteria are derived for the problem, both of which require some type of search procedure to find the desired solution. Simulations are used to show the benefit of using closed-loop sensor control …

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Quasi-Anosov Diffeomorphisms Of 3-Manifolds, Todd L. Fisher, Hertz M. Rodriguez Feb 2009

Quasi-Anosov Diffeomorphisms Of 3-Manifolds, Todd L. Fisher, Hertz M. Rodriguez

Faculty Publications

In 1969, Hirsch posed the following problem: given a diffeomorphism f:N → N and a compact invariant hyperbolic set Λ of f, describe the topology of Λ and the dynamics of f restricted to Λ. We solve the problem where Λ=M^3 is a closed 3-manifold: if M^3 is orientable, then it is a connected sum of tori and handles; otherwise it is a connected sum of tori and handles quotiented by involutions.

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Spamed: A Spam Email Detection Approach Based On Phrase Similarity, Yiu-Kai D. Ng, Maria Soledad Pera Feb 2009

Spamed: A Spam Email Detection Approach Based On Phrase Similarity, Yiu-Kai D. Ng, Maria Soledad Pera

Faculty Publications

Emails are unquestionably one of the most popular communication media these days. Not only they are fast and reliable, but also free in general. Unfortunately, a significant number of emails received by email users on a daily basis are spam. This fact is annoying, since spam emails translate into a waste of user’s time in reviewing and deleting them. In addition, spam emails consume resources, such as storage, bandwidth, and computer processing time. Many attempts have been made in the past to eradicate spam emails; however, none has been proved highly effective. In this paper, we propose a spam-email detection …

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Full Issue Feb 2009

Full Issue

Swiss American Historical Society Review

No abstract provided.

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Myths On Palmyra's Main Street, Donald L. Enders, Jennifer L. Lund Jan 2009

Myths On Palmyra's Main Street, Donald L. Enders, Jennifer L. Lund

Review of Books on the Book of Mormon 1989–2011

Review of Gordon L. Weight. Miracle on Palmyra's Main Street: An “Old-Time” Printer's Perspective on Printing the Original Copies of the Book of Mormon.

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Mormon's Editorial Method And Meta-Message, Brant A. Gardner Jan 2009

Mormon's Editorial Method And Meta-Message, Brant A. Gardner

Review of Books on the Book of Mormon 1989–2011

No abstract provided.

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Two More Waves, Grant Hardy Jan 2009

Two More Waves, Grant Hardy

Review of Books on the Book of Mormon 1989–2011

Review of Robert A. Rees and Eugene England, eds. The Reader's Book of Mormon. and Review of The Book of Mormon. Translated by Joseph Smith. Introduction by Laurie F. Maffly-Kipp.

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Effect Of Land Use-Based Surface Roughness On Hydrologic Model Output Jan 2009

Effect Of Land Use-Based Surface Roughness On Hydrologic Model Output

Journal of Spatial Hydrology

The Manning’s roughness coefficient (n) is commonly used to represent surface roughness in lumped and distributed hydrologic models. Model parameter sensitivity studies identify runoff response to be sensitive to Manning’s n changes. For large watersheds, modelers typically use land use / land cover datasets to assign Manning’s n values based on the use or cover class (e.g., residential, impervious). Although this approach is expected to introduce errors to the simulation results, studies have not adequately assessed the occurrence or magnitude because of the challenge of producing an accurate Manning’s n map to compare to a map produced by the land …

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Book Review, Christian D. Nokkentved Ph.D. Jan 2009

Book Review, Christian D. Nokkentved Ph.D.

Swiss American Historical Society Review

No abstract provided.

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Giuh Based Transfer Function For Gomti River Basin Of India Jan 2009

Giuh Based Transfer Function For Gomti River Basin Of India

Journal of Spatial Hydrology

Geomorphologic instantaneous unit hydrograph (GIUH) can be used as a transfer function for modeling the transformation of excess rainfall into surface runoff, in which excess rainfall is an excitation (i.e. production function) to the hydrologic system. These models can be used to predict / forecast the temporal variation of the surface runoff at the outlet of ungauged basin, which is useful in the hydrologic / environmental engineering applications. The present study deals with the geomorphometric investigation and provides an efficient solution approach to derive the GIUH based transfer function and thus geomorphologic unit hydrograph (GUH) for the basin. Since, Gomti …

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Insights From Research On Distance Education Learners, Learning, And Learner Support, Richard E. West Jan 2009

Insights From Research On Distance Education Learners, Learning, And Learner Support, Richard E. West

Faculty Publications

This article reviews the key ideas related to increasing student learning and support described in selected chapters from the second edition of the Handbook of Distance Education (Moore 2007). These chapters described research findings related to the impact of distance education on learners in general (student autonomy, cognition, social learning, and satisfaction), as well as specific subgroups of distance students and instructors (K-12, female, and disabled students as well as academic advising and library services). This article concludes with brief recommendations for future research in each of these areas.

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Prediction Of Light Gas Composition In Coal Devolatilization, Ravichandra S. Jupudi, Vladimir Zamansky, Thomas H. Fletcher Jan 2009

Prediction Of Light Gas Composition In Coal Devolatilization, Ravichandra S. Jupudi, Vladimir Zamansky, Thomas H. Fletcher

Faculty Publications

The chemical percolation devolatilization (CPD) model describes the devolatilization behavior of rapidly heated coal based on the chemical structure of the coal. It predicts the overall char, tar, and light gas yields. This paper presents an improved CPD model with improved capability for predicting light gas composition. This is achieved by incorporating a kinetic model that simulates the release of various light gas species from their respective sources/functional groups in coal. The improved CPD model is validated using experiments with a wire mesh reactor and published experimental observations

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Flame Interactions And Burning Characteristics Of Two Live Leaf Samples, Brent M. Pickett, Carl Isackson, Rebecca Wunder, Thomas H. Fletcher, Bret W. Butler, David R. Weise Jan 2009

Flame Interactions And Burning Characteristics Of Two Live Leaf Samples, Brent M. Pickett, Carl Isackson, Rebecca Wunder, Thomas H. Fletcher, Bret W. Butler, David R. Weise

Faculty Publications

Combustion experiments were performed over a flat-flame burner that provided the heat source for multiple leaf samples. Interactions of the combustion behavior between two leaf samples were studied. Two leaves were placed in the path of the flat-flame burner, with the top leaf 2.5 cm above the bottom leaf. Local gas and particle temperatures, as well as local oxygen concentrations, were measured along with burning characteristics of both leaves. Results showed that the time to ignition of the upper leaf was not significantly affected by the presence of the lower leaf. The major difference observed was that the time of …

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Tpack Development In Science Teaching: Measuring The Tpack Confidence Of Inservice Science Teachers, Charles R. Graham, Nicolette Burgoyne, Pamela Cantrell, Leigh Smith, Larry St. Clair, Ron Harris Jan 2009

Tpack Development In Science Teaching: Measuring The Tpack Confidence Of Inservice Science Teachers, Charles R. Graham, Nicolette Burgoyne, Pamela Cantrell, Leigh Smith, Larry St. Clair, Ron Harris

Faculty Publications

Knowledge related to the effective use of educational technologies has become widely recognized as an important aspect of an educator’s knowledge-base for the 21st Century (ISTE, 2008; National Council for Accreditation of Teacher Education, 1997; Partnership for 21st Century Skills, 2003). Early in the history of educational technology, educators were taught in technology classes that focused primarily on technology skills independent from the pedagogical or content courses (Graham, Culatta, Pratt, & West, 2004; Hargrave & Hsu, 2000; Willis & Mehlinger, 1996). Educators soon recognized that technology skills alone did not serve them well because one could know how to operate …

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The Need For Ecumenical, Denominational And Empirically-Supported Christian Psychotherapy Approaches In Public Settings, P. Scott Richards Jan 2009

The Need For Ecumenical, Denominational And Empirically-Supported Christian Psychotherapy Approaches In Public Settings, P. Scott Richards

Faculty Publications

James Skillen has written an important and broad- ranging article about the place of Christian counseling in public settings. I will focus my brief comments on what I regard as some of the implications of the following statement: "You ought to be able to conduct your counseling and psychiatric practices in a thoroughly Christian manner within a public or semi-public accrediting system that provides public-legal protection and equal access for a diverse range of professional and disciplinary approaches. You should not have to stuff your practice into a private box if it is distinctively Christian any more than another professional …

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Religion And Academic Achievement Among Adolescents, Benjamin Mckune, John P. Hoffmann Jan 2009

Religion And Academic Achievement Among Adolescents, Benjamin Mckune, John P. Hoffmann

Faculty Publications

In this article, we examine the association between religiosity and academic achievement among adolescents. Recent research demonstrates a positive association between religiosity and academic success. However, some studies show that this association is due to family and community factors; for example, variation in levels of family capital among religious affiliates could explain it. Yet whether religious factors affect academic achievement among adolescents might also be due to the concordance or discordance of religiosity between parents and their children. Using data for two years from the National Longitudinal Study of Adolescent Health, we examine the associationbetween adolescents‘ religiosity, parents‘ religiosity, and …

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Author Entropy Vs. File Size In The Gnome Suite Of Applications, Jason R. Casebolt, Daniel P. Delorey, Charles D. Knutson, Jonathan Krein, Alexander C. Maclean Jan 2009

Author Entropy Vs. File Size In The Gnome Suite Of Applications, Jason R. Casebolt, Daniel P. Delorey, Charles D. Knutson, Jonathan Krein, Alexander C. Maclean

Faculty Publications

We present the results of a study in which author entropy was used to characterize author contributions per file. Our analysis reveals three patterns: banding in the data, uneven distribution of data across bands, and file size dependent distributions within bands. Our re- sults suggest that when two authors contribute to a file, large files are more likely to have a dominant author than smaller files.

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Synthesizing Correlated Rss News Articles Based On A Fuzzy Equivalence Relation, Yiu-Kai D. Ng, Maria Soledad Pera Jan 2009

Synthesizing Correlated Rss News Articles Based On A Fuzzy Equivalence Relation, Yiu-Kai D. Ng, Maria Soledad Pera

Faculty Publications

Tens of thousands of news articles are posted on-line each day, covering topics from politics to science to current events. To better cope with this overwhelming volume of information, RSS (news) feeds are used to categorize newly posted articles. Nonetheless, most RSS users must filter through many articles within the same or different RSS feeds to locate articles pertaining to their particular interests. Due to the large number of news articles in individual RSS feeds, there is a need for further organizing articles to aid users in locating non-redundant, informative, and related articles of interest quickly. In this paper, we …

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Piezoresistive Feedback Control Of A Mems Thermal Actuator, Robert K. Messenger, Quentin Theodore Aten, Timothy W. Mclain, Larry L. Howell Jan 2009

Piezoresistive Feedback Control Of A Mems Thermal Actuator, Robert K. Messenger, Quentin Theodore Aten, Timothy W. Mclain, Larry L. Howell

Faculty Publications

Feedback control of MEMS devices has the potential to significantly improve device performance and reliability. One of the main obstacles to its broader use is the small number of on-chip sensing options available to MEMS designers. A method of using integrated piezoresistive sensing is proposed and demonstrated as another option. Integrated piezoresistive sensing utilizes the inherent piezoresistive property of polycrystalline silicon from which many MEMS devices are fabricated. As compliant MEMS structure’s flex to perform their functions, their resistance changes. That resistance change can be used to transduce the structures’ deflection into an electrical signal. The piezoresistive microdisplacement transducer (PMT) …

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