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2014

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Engineering Faculty Views Of Teaching Quality, Accreditation, And Institutional Climate And How They Influence Teaching Practices, Jacqueline C. Mcneil Oct 2014

Engineering Faculty Views Of Teaching Quality, Accreditation, And Institutional Climate And How They Influence Teaching Practices, Jacqueline C. Mcneil

Open Access Dissertations

There is wide agreement that teaching quality matters in higher education, but faculty have varied ideas about the definition of quality. This dissertation examined data from a survey administered in 1997, 1999, and 2002 at institutions of the Southeastern University and College Coalition for Engineering Education (SUCCEED) supplemented by a survey administered more recently to a subset of those institutions and two additional institutions. All participating institutions are large public universities. The data collected included faculty teaching practices and three influences on those practices—the faculty member’s definition of quality teaching, their perspective on ABET accreditation processes, and the climate for …

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Trajectory Design In The Spatial Circular Restricted Three-Body Problem Exploiting Higher-Dimensional Poincare Maps, Amanda F. Haapala Oct 2014

Trajectory Design In The Spatial Circular Restricted Three-Body Problem Exploiting Higher-Dimensional Poincare Maps, Amanda F. Haapala

Open Access Dissertations

In this investigation, the role of higher-dimensional Poincaré maps in facilitating trajectory design is explored for a variety of applications. To begin, existing strategies to implement Poincaré maps for trajectory design applications in the spatial CR3BP are evaluated. New applications for these strategies are explored, including an analysis of the natural motion of Jupiter-family comets that experience temporary capture about Jupiter, and the search for periodic orbits in the vicinity of the primary bodies in the spatial problem. Because current strategies to represent higher-dimensional maps, generally, lead to a loss of information, new approaches to represent all information contained in …

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The Impact Of National Science Foundation Investments In Undergraduate Engineering Education Research: A Comparative, Mixed Methods Study, Jeremi Shavonda London Oct 2014

The Impact Of National Science Foundation Investments In Undergraduate Engineering Education Research: A Comparative, Mixed Methods Study, Jeremi Shavonda London

Open Access Dissertations

The U.S. invests billions of taxpayers' dollars in research tied to the national priorities that contribute to its competitiveness in a global economy. As the federal funding agency with an explicit focus on engineering education, the National Science Foundation (NSF) contains a portfolio of projects focused on improving the quantity of engineering graduates and the quality of engineering programs. Within the agency, the Division of Undergraduate Education invests approximately $190 million (FY 2012) annually on science, technology, engineering and mathematics (STEM) education projects. Although the DUE portfolio includes a suite a projects with different foci supporting national initiatives and Principal …

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Culturally Responsive Engineering Education: A Case Study Of A Pre-College Introductory Engineering Course At Tibetan Children's Village School Of Selakui, Marisol Mercado Santiago Oct 2014

Culturally Responsive Engineering Education: A Case Study Of A Pre-College Introductory Engineering Course At Tibetan Children's Village School Of Selakui, Marisol Mercado Santiago

Open Access Dissertations

Culturally responsive teaching has been argued to be effective in the education of Indigenous youth. This approach emphasizes the legitimacy of a group's cultural heritage, helps to associate abstract academic knowledge with the group's sociocultural context, seeks to incorporate a variety of strategies to engage students who have different learning styles, and strives to integrate multicultural information in the educational contents, among other considerations. ^ In this work, I explore the outcomes of a culturally responsive introductory engineering short course that I developed and taught to Tibetan students at Tibetan Children's Village of Selakui (in Uttarakhand, India). Based on my …

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Theory Of Density Functionals, Martin A. Mosquera-Tabares Oct 2014

Theory Of Density Functionals, Martin A. Mosquera-Tabares

Open Access Dissertations

Density functional theory is an alternative quantum mechanical theory that offers simple ways of performing calculations of the electronic properties of matter. Many different methods derive from density functional theory. The most appealing for its simplicity and rigor is the theory of Kohn and Sham. In this thesis I propose new methods in density-functional theory that are helpful to address some important problems in the application of the local-density approximation within Kohn-Sham DFT to the analysis of ground-states and dynamical properties of electronic systems.

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Structural Characterization Of Multimetallic Nanoparticles, Vineetha Mukundan Oct 2014

Structural Characterization Of Multimetallic Nanoparticles, Vineetha Mukundan

Open Access Dissertations

Bimetallic and trimetallic alloy nanoparticles have enhanced catalytic activities due to their unique structural properties. Using in situ time-resolved synchrotron based x-ray diffraction, we investigated the structural properties of nanoscale catalysts undergoing various heat treatments. Thermal treatment brings about changes in particle size, morphology, dispersion of metals on support, alloying, surface electronic properties, etc. First, the mechanisms of coalescence and grain growth in PtNiCo nanoparticles supported on planar silica on silicon were examined in detail in the temperature range 400-900°C. The sintering process in PtNiCo nanoparticles was found to be accompanied by lattice contraction and L10chemical ordering. …

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Excited States Of Chromophores And Vibronic Interactions, Benjamin T. Nebgen Oct 2014

Excited States Of Chromophores And Vibronic Interactions, Benjamin T. Nebgen

Open Access Dissertations

The main focus of my Ph.D. work has been on building a vibronic coupling model for multichromophores and extending that model to more general systems. This Dissertation serves as both a summary of this work as well as a manual for the two vibronic coupling programs I have written. It is my hope that the instructions written here are complete enough for any who would like to replicate my work on vibronic coupling on other systems. ^ Additionally, I have also worked on a few purely computational projects not directly related to the vibronic coupling work. The status of these …

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Advanced Iii-V / Si Nano-Scale Transistors And Contacts: Modeling And Analysis, Seung Hyun Park Oct 2014

Advanced Iii-V / Si Nano-Scale Transistors And Contacts: Modeling And Analysis, Seung Hyun Park

Open Access Dissertations

The exponential miniaturization of Si CMOS technology has been a key to the electronics revolution. However, the continuous downscaling of the gate length becomes the biggest challenge to maintain higher speed, lower power, and better electrostatic integrity for each following generation. Hence, novel devices and better channel materials than Si are considered to improve the metal-oxide-semiconductor field-effect transistors (MOSFETs) device performance. III-V compound semiconductors and multi-gate structures are being considered as promising candidates in the next CMOS technology. III-V and Si nano-scale transistors in different architectures are investigated (1) to compare the performance between InGaAs of III-V compound semiconductors and …

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Structure-Functionality Relationship Of Collagen Scaffolds For Tissue Engineering, Seungman Park Oct 2014

Structure-Functionality Relationship Of Collagen Scaffolds For Tissue Engineering, Seungman Park

Open Access Dissertations

Tissue engineering is a promising technology that enables scientists to create artificial organs or replace damaged tissues using animal cells and other components. For successful tissue regeneration, many factors should be taken into account, however, three components are most crucial: cell, scaffold, and soluble factor(s). In order to check the functionality after regeneration of desired tissues, various approaches have been attempted, depending on the physical, biological, and chemical properties of the tissues. Recently, the importance of the extracellular matrix (ECM) microstructure is being considered to be important in this regard. The ECM is closely associated with various functional properties of …

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Energy Production, Distribution, And Pollution Controls: Combining Engineering And Economic Analysis To Enhance Efficiency And Policy Design, David F. Perkis Oct 2014

Energy Production, Distribution, And Pollution Controls: Combining Engineering And Economic Analysis To Enhance Efficiency And Policy Design, David F. Perkis

Open Access Dissertations

Three published articles are presented which focus on enhancing various aspects of the energy supply chain. While each paper adopts a different methodology, all three combine engineering data and/or techniques with economic analysis to improve efficiency or policy design within energy markets. ^ The first paper combines a chemical engineering plant design model with an economic assessment of product enhancements within an ethanol production facility. While a new chemical process is shown to achieve greater ethanol yields, the animal feed by-products are denatured and decrease in value due to the degradation of a key nutritional amino acid. Overall, yield increases …

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Non-Intrusive Two-Phase Flow Regime Identification And Transport Characterization In Microchannels Subject To Uniform And Non-Uniform Heat Input, Susan N. Ritchey Oct 2014

Non-Intrusive Two-Phase Flow Regime Identification And Transport Characterization In Microchannels Subject To Uniform And Non-Uniform Heat Input, Susan N. Ritchey

Open Access Dissertations

Direct integration of compact microchannel heat sinks is an attractive thermal management solution for the dissipation of high heat fluxes, specifically under boiling conditions that provide high rates of heat transfer at a uniform heat sink temperature. Under two-phase flow conditions, the heat transfer and pressure drop are a function of the local flow regime. Development of sensors that detect local void fraction and flow regimes may enable better understanding of the fundamental flow phenomena. ^ The void fraction in air-water two-phase adiabatic flow in a microchannel is measured in this work using a custom-designed impedance-based sensor with electrodes on …

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Migratory Ecology Of Sea Turtles, Nathan Jack Robinson Oct 2014

Migratory Ecology Of Sea Turtles, Nathan Jack Robinson

Open Access Dissertations

Establishing the movement patterns of free-ranging animals is imperative to understanding their behavior and ecology, and is often necessary for designing effective conservation-strategies. This is especially true for migratory species, such as sea turtles, whose long-distance movements form a major component of their life history. In this thesis, I investigated which factors are driving the migratory behavior of the leatherback turtleDermochelys coriacea. Firstly, I examined whether the timing of the nesting season (nesting phenology) is influenced by oceanographic conditions along the pre-nesting migratory route or by variation in population structure. The discovery that nesting phenology appears more influenced by …

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Soil Quality And Nitrogen Cycling Dynamics Altered By Fertility Amendments In Intensively Managed Vegetable Production Systems, Matt A. Rudisill Oct 2014

Soil Quality And Nitrogen Cycling Dynamics Altered By Fertility Amendments In Intensively Managed Vegetable Production Systems, Matt A. Rudisill

Open Access Dissertations

Fresh market vegetable production in the Midwest U.S. is growing rapidly as a result of increased demand for locally-sourced food. High tunnels are becoming increasingly popular among Midwest vegetable growers as these structures offer many production benefits including season extension. However, vegetables require substantial fertility inputs, particularly nitrogen (N), in order to meet desired levels of productivity, and some fertility management strategies can negatively impact soil and environmental quality. This can be particularly problematic in high tunnels, where longer production periods and modification of the growing environment put these systems at greater risk for soil degradation. Identification of fertility practices …

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A New Passive Surface Water Flux Meter For Simultaneous Measurement Of Contaminant And Water Fluxes In Streams And Rivers, Stephen A. Sassman Oct 2014

A New Passive Surface Water Flux Meter For Simultaneous Measurement Of Contaminant And Water Fluxes In Streams And Rivers, Stephen A. Sassman

Open Access Dissertations

A passive surface water flux meter (PSFM) for measurement of contaminant concentration/flux in rivers and streams is described and tested. The novel PSFM design was developed for portability and ease of adaptability for a variety of contaminant classes. Although previous designs have been evaluated under constant flow conditions, the PSFM has never been used for measurement of pesticides or hormones and this is the first time that it has been tested under transient flow. Discharge through the PSFM is assessed by measuring miscible displacement of alcohol tracers from granular activated carbon (GAC). The tracer retardation factors (R) measured by miscible …

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Relation Among Images: Modelling, Optimization And Applications, Bin Shen Oct 2014

Relation Among Images: Modelling, Optimization And Applications, Bin Shen

Open Access Dissertations

In the last two decades, the increasing popularity of information technology has led to a dramatic increase in the amount of visual data. Many applications are developed by processing, analyzing and understanding such increasing data; and modelling the relation among images is fundamental to success of many of them. Examples include image classification, content-based image retrieval and face recognition. Given signatures of images, there are many ways to depict the relation among them, such as pairwise distance, kernel function and factor analysis. However, existing methods are still insufficient as they suffer from many real factors such as misalignment of images …

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Theory Of Topological Insulators And Its Applications, Parijat Sengupta Oct 2014

Theory Of Topological Insulators And Its Applications, Parijat Sengupta

Open Access Dissertations

An important pursuit in semiconductor physics is to discover new materials to sustain the continuous progress and improvements in the current electronic devices. Traditionally, three material types are in use: 1) Metals 2) Semiconductors 3) Insulators. All the three material types are classified according to the energy gap between conduction and valence bands derived from band theory of solids. Recent theoretical predictions and confirmed by experimental observations have provided evidence that there exists materials which behave as insulators in the bulk but possess gapless conducting states on the surface. These new class of materials are called topological insulators (TI). In …

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Scaling Finite Difference Methods In Large Eddy Simulation Of Jet Engine Noise To The Petascale: Numerical Methods And Their Efficient And Automated Implementation, Yingchong Situ Oct 2014

Scaling Finite Difference Methods In Large Eddy Simulation Of Jet Engine Noise To The Petascale: Numerical Methods And Their Efficient And Automated Implementation, Yingchong Situ

Open Access Dissertations

Reduction of jet engine noise has recently become a new arena of competition between aircraft manufacturers. As a relatively new field of research in computational fluid dynamics (CFD), computational aeroacoustics (CAA) prediction of jet engine noise based on large eddy simulation (LES) is a robust and accurate tool that complements the existing theoretical and experimental approaches. In order to satisfy the stringent requirements of CAA on numerical accuracy, finite difference methods in LES-based jet engine noise prediction rely on the implicitly formulated compact spatial partial differentiation and spatial filtering schemes, a crucial component of which is an embedded solver for …

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A Multilevel Analysis Of Project Lead The Way Implementation In Indiana, Brandon H. Sorge Oct 2014

A Multilevel Analysis Of Project Lead The Way Implementation In Indiana, Brandon H. Sorge

Open Access Dissertations

Using data from the 2010 Indiana public high school graduating class (N=55612), this project employed a multi-level analysis to determine, what if any differences occurred in majoring in STEM and freshman to sophomore year persistence, between students attending a school that offers Project Lead the Way and students that don't, while controlling for being a PLTW student. Additionally, this project explored the mitigating institutional factors that influenced a student majoring in STEM or persisting from their freshman to sophomore year in post-secondary education and if and how these factors varied depending upon if a student took PLTW courses, attended a …

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Understanding Preferred Leg Stiffness And Layered Control Strategies For Locomotion, Zhuohua H. Shen Oct 2014

Understanding Preferred Leg Stiffness And Layered Control Strategies For Locomotion, Zhuohua H. Shen

Open Access Dissertations

Despite advancement in the field of robotics, current legged robots still cannot achieve the kind of locomotion stability animals and humans have. In order to develop legged robots with greater stability, we need to better understand general locomotion dynamics and control principles. Here we demonstrate that a mathematical modeling approach could greatly enable the discovery and understanding of general locomotion principles. ^ It is found that animal leg stiffness when scaled by its weight and leg length falls in a narrow region between 7 and 27. Rarely in biology does such a universal preference exist. It is not known completely …

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Evaluation Of Yttrium-90 Positron Emission Tomography Dosimetry, Katherine N. Tapp Oct 2014

Evaluation Of Yttrium-90 Positron Emission Tomography Dosimetry, Katherine N. Tapp

Open Access Dissertations

Purpose: Radioembolization is a novel treatment which utilizes the liver's unique dual system blood supply to trap yttrium-90 (90Y) microspheres in microvasculature near liver tumors. Radioembolization dose planning and dosimetry are based on crude, inaccurate assumptions due to the lack of knowledge of patient specific 90Y microsphere distribution. In recent years, the very small 3.1867e-5 internal pair production decay branch of 90Y has been shown to allow for positron emission tomography (PET) imaging following radioembolization. This work explores the accuracy and limitation of 90Y PET imaging due to the extremely low signal to noise (SNR) …

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Digital Provenance - Models, Systems, And Applications, Salmin Sultana Oct 2014

Digital Provenance - Models, Systems, And Applications, Salmin Sultana

Open Access Dissertations

Data provenance refers to the history of creation and manipulation of a data object and is being widely used in various application domains including scientific experiments, grid computing, file and storage system, streaming data etc. However, existing provenance systems operate at a single layer of abstraction (workflow/process/OS) at which they record and store provenance whereas the provenance captured from different layers provide the highest benefit when integrated through a unified provenance framework. To build such a framework, a comprehensive provenance model able to represent the provenance of data objects with various semantics and granularity is the first step. In this …

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Optical Spectroscopy And Langmuir Probe Diagnostics Of Microwave Plasma In Synthesis Of Graphene-Based Nanomaterials, Alfredo D. Tuesta Oct 2014

Optical Spectroscopy And Langmuir Probe Diagnostics Of Microwave Plasma In Synthesis Of Graphene-Based Nanomaterials, Alfredo D. Tuesta

Open Access Dissertations

Along with the revolutionary discovery and development of carbon nanostructures, such as carbon nanotubes and graphitic sheets, has arrived the potential for their application in the fields of medicine, bioscience and engineering due to their exceptional structural, thermal and electrical properties. As roll-to-roll plasma deposition systems begin to provide means for large scale production of these nanodevices, a detailed understanding of the environment responsible for their synthesis is imperative in order to more accurately design and control the growth of carbon nanodevices. To date, the understanding of the chemistry and kinetics that govern the synthesis of carbon nanodevices is only …

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Algebraic Level Sets For Cad/Cae Integration And Moving Boundary Problems, Kritika Upreti Oct 2014

Algebraic Level Sets For Cad/Cae Integration And Moving Boundary Problems, Kritika Upreti

Open Access Dissertations

Boundary representation (B-rep) of CAD models obtained from solid modeling kernels are commonly used in design, and analysis applications outside the CAD systems. Boolean operations between interacting B-rep CAD models as well as analysis of such multi-body systems are fundamental operations on B-rep geometries in CAD/CAE applications. However, the boundary representation of B-rep solids is, in general, not a suitable representation for analysis operations which lead to CAD/CAE integration challenges due to the need for conversion from B-rep to volumetric approximations. The major challenges include intermediate mesh generation step, capturing CAD features and associated behavior exactly and recurring point containment …

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Rational Multiparty Computation, John Ross Wallrabenstein Oct 2014

Rational Multiparty Computation, John Ross Wallrabenstein

Open Access Dissertations

The field of rational cryptography considers the design of cryptographic protocols in the presence of rational agents seeking to maximize local utility functions. This departs from the standard secure multiparty computation setting, where players are assumed to be either honest or malicious. ^ We detail the construction of both a two-party and a multiparty game theoretic framework for constructing rational cryptographic protocols. Our framework specifies the utility function assumptions necessary to realize the privacy, correctness, and fairness guarantees for protocols. We demonstrate that our framework correctly models cryptographic protocols, such as rational secret sharing, where existing work considers equilibrium concepts …

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Structured Deterministic Models Applied To Malaria And Other Endemic Diseases, Katia Patricia Vogt Geisse Oct 2014

Structured Deterministic Models Applied To Malaria And Other Endemic Diseases, Katia Patricia Vogt Geisse

Open Access Dissertations

This thesis includes modeling studies on three structured deterministic models. These models are used to study the disease dynamics of malaria or the joint disease dynamics of HIV and HSV-2. Each of the models includes multiple components containing individuals in various epidemiological classes for the purpose of addressing questions that are of interests to biologists and epidemiologists. Some of the compartments have a continuous age-structure, which is necessary for studying the specific biological questions under investigation.^ In Chapter 2 a chronological-age structured deterministic model for malaria is presented. The model includes the human and mosquito populations with the human population …

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Coal Gasification For Fuel Synthesis: Multiphysics Modeling And New Concepts, Jian Xu Oct 2014

Coal Gasification For Fuel Synthesis: Multiphysics Modeling And New Concepts, Jian Xu

Open Access Dissertations

Fuel synthesis through gasification of carbonaceous materials (e.g. coal and biomass) has the potential to provide a solution to the increasing demand for energy and liquid transportation fuels. To theoretically understand the complex physical and chemical processes in a gasifier and to identify the most influential parameters for syngas production, we first developed a multi-physics and multi-scale model to simulate the gasification processes in a well-stirred reactor. This model is the first of its kind and considers detailed gas-phase chemistry, particle-phase reactions, moisture drying, devolatilization, porous structure evolution, convective and radiative heat transfer, as well as full coupling between the …

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An Exploratory Factor Analysis And Reliability Analysis Of The Student Online Learning Readiness (Solr) Instrument, Taeho Yu Oct 2014

An Exploratory Factor Analysis And Reliability Analysis Of The Student Online Learning Readiness (Solr) Instrument, Taeho Yu

Open Access Dissertations

The purpose of this study was to develop an effective instrument to measure student readiness in online learning with reliable predictors of online learning success factors such as learning outcomes and learner satisfaction. The validity and reliability of the Student Online Learning Readiness (SOLR) instrument were tested using Exploratory Factor Analysis (EFA) and reliability analysis. Twenty items from three competencies, i.e. social competencies, communication competencies, and technical competencies, were designated for the initial instrument based on the Student Online Learning Readiness (SOLR) Model as a new conceptual model. An exploratory factor analysis (EFA) revealed that four factor-structures of the instrument …

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Relationships Between Lexical Proficiency And L2 Oral Proficiency, Yunjung You Oct 2014

Relationships Between Lexical Proficiency And L2 Oral Proficiency, Yunjung You

Open Access Dissertations

Lexical proficiency is strongly correlated with L2 productive language ability (Crossley, Salsbury, & McNamara, 2011; Laufer & Nation, 1995). While many studies have investigated the relationship between lexical proficiency and L2 writing ability, not many studies have been conducted in terms of spoken language. Also, few studies have focused on how non-native English speakers with different L1 backgrounds differently or similarly develop lexical proficiency in L2 speaking. Based on this background, the present study is conducted with three purposes: 1) to compare the effectiveness of measures of lexical proficiency in terms of their ability to predict the quality of L2 …

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Nonparametric Variable Selection And Dimension Reduction Methods And Their Applications In Pharmacogenomics, Jingyi Zhu Oct 2014

Nonparametric Variable Selection And Dimension Reduction Methods And Their Applications In Pharmacogenomics, Jingyi Zhu

Open Access Dissertations

Nowadays it is common to collect large volumes of data in many fields with an extensive amount of variables, but often a small or moderate number of samples. For example, in the analysis of genomic data, the number of genes can be very large, varying from tens of thousands to several millions, whereas the number of samples is several hundreds to thousands. Pharmacogenomics is an example of genomics data analysis that we are considering here. Pharmacogenomics research uses whole-genome genetic information to predict individuals' drug response. Because whole-genome data are high dimensional and their relationships to drug response are complicated, …

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Image Analysis Using Visual Saliency With Applications In Hazmat Sign Detection And Recognition, Bin Zhao Oct 2014

Image Analysis Using Visual Saliency With Applications In Hazmat Sign Detection And Recognition, Bin Zhao

Open Access Dissertations

Visual saliency is the perceptual process that makes attractive objects "stand out" from their surroundings in the low-level human visual system. Visual saliency has been modeled as a preprocessing step of the human visual system for selecting the important visual information from a scene. We investigate bottom-up visual saliency using spectral analysis approaches. We present separate and composite model families that generalize existing frequency domain visual saliency models. We propose several frequency domain visual saliency models to generate saliency maps using new spectrum processing methods and an entropy-based saliency map selection approach. A group of saliency map candidates are then …

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