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All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

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Heterogeneous And Homogeneous Nickel-Based Electrocatalysts For Oxygen Evolution And Carbon Dioxide Reduction, Meili Sheng May 2016

Heterogeneous And Homogeneous Nickel-Based Electrocatalysts For Oxygen Evolution And Carbon Dioxide Reduction, Meili Sheng

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The growing global energy demand and the increasing concentration of CO2 in the atmosphere have encouraged the development of renewable energy to replace carbon-based fossil fuels. Electrocatalytic water splitting to form H2 and O2 and reduction of CO2 to CO are appealing processes and we can be directly utilize H2 and CO as fuels or commodity chemicals in mature industrial processes, which will not alter the current carbon cycle. However, the O2 evolution reaction of water splitting is a reaction of four-proton and four-electron transfer process, whose kinetics is very sluggish under normal conditions. …


Improving The Scalability And Usability Of The Public Information Officer Monitoring Application, Rohan D. Shah Aug 2015

Improving The Scalability And Usability Of The Public Information Officer Monitoring Application, Rohan D. Shah

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis work addresses the limitations of a web application called the Public Information Officer Monitoring Application (PMA). This application helps Public Information Officers (PIOs) to gather, monitor, sort, store, and report social media data during a crisis event. Before this work, PMA was unable to handle large data sets and as a result, it had not been adequately tested with potential users of the application.

This thesis describes changes made to PMA to improve its ability to handle large data sets. After these changes were made, the application was then tested with target users. All test participants found the …


Face Recognition Under Varying Illuminations, Mohammadreza Faraji Aug 2015

Face Recognition Under Varying Illuminations, Mohammadreza Faraji

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Face recognition under illumination is really challenging. This dissertation proposes four effective methods to produce illumination-invariant features for images with various levels of illuminations. The proposed methods are called logarithmic fractal dimension (LFD), eight local directional patterns (ELDP), adaptive homomorphic eight local directional pat- terns (AH-ELDP), and complete eight local directional patterns (CELDP), respectively.

LFD, employing the log function and the fractal analysis (FA), produces a logarithmic fractal dimension (LFD) image that is illumination-invariant. The proposed FA feature-based method is an effective edge enhancer technique to extract and enhance facial features such as eyes, eyebrows, nose, and mouth.

The proposed …


Learning From The Teaching Practices Of Successful Teachers Of Latina And Latino Students, Glori H. Smith Aug 2015

Learning From The Teaching Practices Of Successful Teachers Of Latina And Latino Students, Glori H. Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study, sponsored by the Department of Teacher Education and Leadership at Utah State University, was to determine the classroom practices and attitudes of the teachers that had been identified as successful with Latina and Latino students at an urban middle school. Criteria for successful teachers were not determined by the researcher, but by those school stakeholders who were asked to nominate such teachers: the administrators, faculty, and parents of Latina/o students.

The difference between the achievement of White students and students of color has long been a concern of educators. It is well established that critical …


Long-Term Study Of Crowdfunding Platform: Predicting Project Success And Fundraising Amount, Jinwook Chung Aug 2015

Long-Term Study Of Crowdfunding Platform: Predicting Project Success And Fundraising Amount, Jinwook Chung

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Crowdfunding that is the combination word of crowdsourcing and funding makes people can start a business easily. Legislating JOBS act in US played a major role in removing restricted barriers of crowdfunding on public offerings of fence and private funds for small business. The growth speed of crowdfunding takes some beating. Through Kickstarter that is a popular crowdfunding platform and being considered the typical case of crowdfunding, 480 million dollars and more than half a billion dollars were invested in about 19 thousand and 22 projects for 2013 and 2014 respectively. But in spite of the rapid growth, the successful …


Organizational Adaptation In Local Stormwater Governance, Andrea Armstrong Aug 2015

Organizational Adaptation In Local Stormwater Governance, Andrea Armstrong

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Much of the past research and policy analysis on issues of western water has focused on inter-basin river agreements, large infrastructure that captures and distributes water, and conflict between agricultural and urban water demands. My dissertation asks a set of different questions:

How is water governed and managed within communities of Utah?

How are the organizations that manage water responding to changes in population, water availability, and water quality policy?

The answers to these questions are essential for understanding the ways in which changes to water quantity and quality will be addressed in the present and coming years. To better …


Virulence Evolution Of Fungal Pathogens In Social And Solitary Bees With An Emphasis On Multiple Infections, Ellen G. Klinger Aug 2015

Virulence Evolution Of Fungal Pathogens In Social And Solitary Bees With An Emphasis On Multiple Infections, Ellen G. Klinger

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The health of pollinators, especially bees, is of the utmost importance to success of many agricultural ecosystems. Microorganisms can cause diseases in bees; such microbes are pathogenic. The ability of a pathogen to cause harm to its host (such as a bee) is termed its virulence. Studying the evolution of different levels of virulence can lead researchers to a better understanding of pathogens, and potentially predict how much harm a pathogen can cause in the future. We studied the evolution of virulence levels for a fungal disease of bees. This group of fungi is composed of 28 species, and some …


Image Blur Detection With Two-Dimensional Haar Wavelet Transform, Sarat Kiran Andhavarapu Aug 2015

Image Blur Detection With Two-Dimensional Haar Wavelet Transform, Sarat Kiran Andhavarapu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Efficient detection of image blur and its extent is an open research problem in computer vision. Image blur has a negative impact on image quality. Blur is introduced into images due to various factors including limited contrast, improper exposure time or unstable device handling. Toward this end, an algorithm is presented for image blur detection with the use of Two-Dimensional Haar Wavelet transform (2D HWT). The algorithm is experimentally compared with two other image blur detection algorithms frequently cited in the literature. When evaluated over a sample of images, the algorithm performed on par or better than the two other …


The Colorado Plateau As A Virtual Laboratory For Mobile Games For Geoscience Education And Relations Between Rock Strength And River Metrics, Natalie Bursztyn Aug 2015

The Colorado Plateau As A Virtual Laboratory For Mobile Games For Geoscience Education And Relations Between Rock Strength And River Metrics, Natalie Bursztyn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation encompasses two studies: one developing virtual field trips for mobile devices for an innovative approach to lower-division geoscience education, and the other examining the role of rock strength in river erosion and landscape evolution.

The education study involves the development of three virtual field trip modules (Geologic Time, Geologic Structures, and Hydrologic Processes, all free on iTunes and Google Play) that lead students down a virtual Colorado River through Grand Canyon by physically moving around their campus quad, football field or other location, using their GPS-equipped smart phone or tablet. As students reach each location in the scaled …


Detecting Experts On Quora: By Their Activity, Quality Of Answers, Linguistic Characteristics And Temporal Behaviors, Sumanth Kumar Reddy Nagarur Patil Aug 2015

Detecting Experts On Quora: By Their Activity, Quality Of Answers, Linguistic Characteristics And Temporal Behaviors, Sumanth Kumar Reddy Nagarur Patil

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Question and answering sites are useful in sharing the knowledge by answering questions. It is a medium of sharing knowledge. Quora is the fastest emerging effective Q&A site, which is the best source of knowledge. Here you can ask a question, and get help in getting answers from people with firsthand experience, and blog about what you know. In this paper, we are investigating and identifying potential experts who are providing the best solutions to the questioner needs. We have considered several techniques in identifying user as an expert or non-expert. We have targeted the most followed topics in Quora …


The Effects Of Interactive Computer Simulation And Animation On Student Learning Of Rigid Body Dynamics: A Mixed Method Study, Oai Ha Aug 2015

The Effects Of Interactive Computer Simulation And Animation On Student Learning Of Rigid Body Dynamics: A Mixed Method Study, Oai Ha

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Engineering Dynamics (ED) courses are known as challenging and demanding for undergraduate students majored in many engineering fields, such as mechanical and aerospace engineering and civil and environmental engineering. The course is built upon the foundation and framework of mathematics and physics and requires students to have strong abstract thinking and reasoning skills. Rigid body dynamics (RBD), the second part of ED, investigates kinematics and kinetics of rigid bodies and is considered as a difficult subject by many undergraduate students because the course requires them to visualize abstract objects in motions. Although there have been many studies reporting the uses …


Attacker-Induced Traffic Flow Instability In A Stream Of Automated Vehicles, Daniel D. Dunn Aug 2015

Attacker-Induced Traffic Flow Instability In A Stream Of Automated Vehicles, Daniel D. Dunn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Highway systems world wide continue to see an ever increased number of vehicles and subsequently a rise in congested traffic. This results in longer commute times, wasted energy as vehicles idle in stop and go traffic, and increases the risk of accidents. In short, increased congestion costs time and money. These issues have prompted much research into Automated Highway Systems (AHS). In AHS vehicles using computer algorithms can safely travel at much smaller inter-vehicle distances than human drivers are capable of. This increases the capacity of existing highway systems. Sensors aboard each vehicle make this possible by monitoring their surroundings. …


Laboratory Study On The Effects Of Exit Face Inclination Of Critical Gradients, Richard Allen Keizer Jr. May 2015

Laboratory Study On The Effects Of Exit Face Inclination Of Critical Gradients, Richard Allen Keizer Jr.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The objective of this research is to help better understand the effects of exit face inclinations on critical gradients. This will lead to more practical ways to predict critical hydraulic gradients and slope stability using soil properties and exit face conditions. Current geotechnical engineering does not consider these factors because they are not thoroughly understood. Despite the attempts to better predict critical gradients, methods developed over 70 years ago to model the heave mechanism are used to model failure mechanisms such as backward erosion (or piping). This critical hydraulic gradient is only calculated by means of the buoyant unit weight …


Statistical Dependence In Imputed High-Dimensional Data For A Colorectal Cancer Study, Anvar Suyundikov May 2015

Statistical Dependence In Imputed High-Dimensional Data For A Colorectal Cancer Study, Anvar Suyundikov

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The research objective of this dissertation was to provide novel statistical methods to fill potential gaps in the analyses of micro-ribonucleic acid (miRNA) data, and consequently to identify the miRNAs that contribute to cancer development. Mainly, this dissertation addressed the statistical issues raised by the statistical dependence of imputed (i.e., the missing data were replaced with substituted values) miRNA data in the colorectal cancer study. This dissertation presented a modified imputation method, the weighted KNN imputation accounting for dependence, that predicted the expression levels of missing normal samples with greater imputation accuracy than other imputation methods, and had moderate power …


Systems Optimization Models To Improve Water Management And Environmental Decision Making, Omar Alminagorta Cabezas May 2015

Systems Optimization Models To Improve Water Management And Environmental Decision Making, Omar Alminagorta Cabezas

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The degradation of water quality and wetlands is one of the most challenging environmental problems around the world. In spite of the magnitude of these environmental problems, few efforts identify how scarce resources (e.g., water, budget) can be more efficiently used to solve these problems. This dissertation presents a set of tools to help solve environmental problems related to excess phosphorus levels in water bodies and wetland degradation caused by water shortages and invasive vegetation. These tools are presented in three studies. The first study presents a simple optimization model that identifies the cost-effective combination of management practices to reduce …


Computational Modeling To Study Disease Development: Applications To Breast Cancer And An In Vitro Model Of Macular Degeneration, Qanita Bani Baker May 2015

Computational Modeling To Study Disease Development: Applications To Breast Cancer And An In Vitro Model Of Macular Degeneration, Qanita Bani Baker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

There have been several techniques developed in recent years to develop computer models of a variety of disease behaviors. Agent-based modeling is a discrete-based modeling approach used agents to represent individual cells that mechanically interact and secrete, consume or react to soluble products. It has become a powerful modeling approach, widely used by computational researchers. In this research, we utilized agent-based modeling to study and explore disease development, particularly in two applications, breast cancer and bioengineering experiments. We further proposed an error-minimization search approach and used it to estimate cellular parameters from multicellular in vitro data.

In this dissertation, in …


Analytical Comparison Of Bovine Parentage Single Nucleotide Polymorphisms, Joshua Jeffrey Dallin May 2015

Analytical Comparison Of Bovine Parentage Single Nucleotide Polymorphisms, Joshua Jeffrey Dallin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Often on cattle operations and dairy farms, where multiple bulls are exposed to cows either by live cover or artificial insemination, error can be present in parentage record keeping for breed registries or production use. Research has evolved to the integration of using single nucleotide polymorphisms (SNPs) to answer questions where cases of unknown parentage may exist. With the evolution of the research, differentiated panels have been created specifically for parentage analysis. Our objective was to complete an analytical comparison between two specific panels, a proven 88 parentage SNP panel and a recently developed 25 SNP panel. A smaller panel …


Tropical Arithmetics And Dot Product Representations Of Graphs, Nicole Turner May 2015

Tropical Arithmetics And Dot Product Representations Of Graphs, Nicole Turner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In tropical algebras we substitute min or max for the typical addition and then substitute addition for multiplication. A dot product representation of a graph assigns each vertex of the graph a vector such that two edges are adjacent if and only if the dot product of their vectors is greater than some chosen threshold. The resultS of creating dot product representations of graphs using tropical algebras are examined. In particular we examine the tropical dot product dimensions of graphs and establish connections to threshold graphs and the threshold dimension of a graph.


Fake And Spam Messages: Detecting Misinformation During Natural Disasters On Social Media, Meet Rajdev May 2015

Fake And Spam Messages: Detecting Misinformation During Natural Disasters On Social Media, Meet Rajdev

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

During natural disasters or crises, users on social media tend to easily believe contents of postings related to the events, and retweet the postings, hoping that the postings will be reached by many other users. Unfortunately, there are malicious users who understand the tendency and post misinformation such as spam and fake messages with expecting wider propagation. To resolve the problem, in this paper we conduct a case study of the 2013 Moore Tornado and Hurricane Sandy. Concretely, we (i) understand behaviors of these malicious users; (ii) analyze properties of spam, fake and legitimate messages; (iii) propose flat and hierarchical …


Computational Prediction And Rational Design Of Novel Clusters, Nanoparticles, And Solid State Materials, Alexander S. Ivanov May 2015

Computational Prediction And Rational Design Of Novel Clusters, Nanoparticles, And Solid State Materials, Alexander S. Ivanov

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The prediction of structure at the atomic level is one of the most fundamental challenges in materials science. Indeed, the structure is arguably the most important piece of information about a material, as it determines pretty much all properties of a material. Knowing the structure, one can analyze a large number of properties of a material, even before it is synthesized – the crucial importance of structure prediction for computational molecular design. This dissertation describes the technique of reliable theoretical predictions and presents the results on the successfully predicted unusual clusters, nanoparticles and solid state materials. The major part of …


Synthesis Of Fluorogenic Probes For Studying Biomass Degradation And Synthesis Of New Antifungal Aminoglycosides, Qian Zhang May 2015

Synthesis Of Fluorogenic Probes For Studying Biomass Degradation And Synthesis Of New Antifungal Aminoglycosides, Qian Zhang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

For the first project, a library of fifteen commercially purchased and synthetic fluorogenic probes were employed for the investigation of biomass degradation using extract of white-rot fungi. These discoveries prove that it is possible to employ fungi for selective degradation or release of hemicelluloses from biomass. This work is supported by Sun Grant Western Regional Center/DOT "Bioprospecting for Enzymes to Break Lignin-Hemicellulose Bond" ($300,000,09/01/2011-08/31/2013)

The second project is focused on synthesizing new aminoglycoside analogs and exploring the potential to revive traditional antibacterial kanamycin as new type of antifungal agents. Although aminoglycosides antibiotics are mainly used as antibacterial agents, this project …


The Onion Name System: Tor-Powered Distributed Dns For Tor Hidden Services, Jesse Victors May 2015

The Onion Name System: Tor-Powered Distributed Dns For Tor Hidden Services, Jesse Victors

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Tor network is a third-generation onion router that aims to provide private and anonymous Internet access to its users. In recent years its userbase, network, and community have grown significantly in response to revelations of national and global electronic surveillance, and it remains one of the most popular anonymity networks in use today. Tor also provides access to anonymous servers known as hidden services – servers of unknown location and ownership that may provide websites, chat services, or an electronic dead drop. These hidden services can be accessed through any Tor-powered web browser but they suffer from usability challenges …


A Study Of The Dayside High-Latitude Ionospheric Electrodynamics During Extended Solar Minimum, Janelle V. Jenniges May 2015

A Study Of The Dayside High-Latitude Ionospheric Electrodynamics During Extended Solar Minimum, Janelle V. Jenniges

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research investigated how electric fields, currents, and charged particles in Earth's high-latitude ionosphere respond to changing input from the sun. The ionosphere surrounds the entire Earth, makes radio communication possible, and can significantly degrade satellite communications and geo-positioning (navigation) capabilities. Many satellites fly within the ionosphere where a solar storm can cause increased satellite drag or destroy onboard electronics. Therefore, understanding and correctly predicting the behavior of this environment is important, and the results from this research will be used to improve current ionospheric models.

A relationship between the level of magnetic activity on Earth due to changes in …


Parameterized Least-Squares Attitude History Estimation And Magnetic Field Observations Of The Auroral Spatial Structures Probe, Ryan J. Martineau May 2015

Parameterized Least-Squares Attitude History Estimation And Magnetic Field Observations Of The Auroral Spatial Structures Probe, Ryan J. Martineau

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As charged particles from the Sun enter the Earth’s atmosphere and create the aurora borealis (Northern lights) and aurora australis (Southern lights), energy is transferred to the atmosphere. In order to better understand the energy transfer processes, the Auroral Spatial Structures Probe rocket was launched to make measurements in the active aurora. Several payloads were deployed by the rocket, each with sensors to measure the magnetic field and the electric field so that the way they change over time and in different positions could be observed. The measurements require accurate knowledge of the spacecraft orientation, and to that end this …


Interactive Computer Simulation And Animation Learning Modules: A Mixed-Method Study Of Their Effects On Students' Problem Solving In Particle Dynamics, Yongquing Guo May 2015

Interactive Computer Simulation And Animation Learning Modules: A Mixed-Method Study Of Their Effects On Students' Problem Solving In Particle Dynamics, Yongquing Guo

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Engineering dynamics is a fundamental core course in many undergraduate engineering curricula. This course is widely regarded as one of the most difficult engineering courses for students to succeed in. A variety of instructional strategies, such as hands-on experimentation, multimedia games, and computer simulation and animation (CSA), have been developed to improve student learning. Among these instructional strategies, CSA has been receiving increasing attention and applications in the international engineering education community. CSA provides students with a visualization tool and a constructivist environment to better understand various engineering problems.

The goal of this dissertation research was to improve student learning …


A Chronostratigraphic Record Of Arroyo Entrenchment And Aggradation In Kanab Creek, Southern Utah, Kirk F. Townsend May 2015

A Chronostratigraphic Record Of Arroyo Entrenchment And Aggradation In Kanab Creek, Southern Utah, Kirk F. Townsend

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study is to explore the processes that lead to the formation of arroyos. Arroyos are entrenched stream channels with steep sides that form by incision into valley-fill sediment, and are common features throughout the southwest United States. Many of these systems formed during the late AD 1800s and early 1900s in one of the most significant historic geomorphic events in the region. At this time, former river floodplains were abandoned, creating terraces. This caused a decline in local water tables and associated changes in stream discharge, vegetative communities, and the ability to irrigate once fertile floodplains. …


Salt And The Rough-Skinned Newt (Taricha Granulosa): Evolutionary Investigations Of Local Adaptation To An Anthropogenic And Natural Stressor, Gareth Rowland Hopkins May 2015

Salt And The Rough-Skinned Newt (Taricha Granulosa): Evolutionary Investigations Of Local Adaptation To An Anthropogenic And Natural Stressor, Gareth Rowland Hopkins

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Amphibians are osmotically-challenged due to their highly permeable skin and egg membranes. As such, biologists have mostly ignored their occurrence in saline habitats. The goal of this dissertation was to investigate the ability of amphibians to adapt to inhabit these osmotically-stressful environments. As freshwater resources are increasingly salinized due to a combination of anthropogenic and natural stressors, including road-deicing salt application, coastal storm events, and sea-level rise, it is important to understand the abilities and constraints of sensitive organisms, like amphibians, to persist in these environments. I began by exploring what is known about amphibians inhabiting saline habitats around the …


Annotation Tools For Multivariate Gene Set Testing Of Non-Model Organisms, Russell K. Banks May 2015

Annotation Tools For Multivariate Gene Set Testing Of Non-Model Organisms, Russell K. Banks

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Microarray chip technology enables researchers to obtain measures of gene activity for essentially all genes in an organism. After grouping genes into biologically meaningful sets, researchers employ certain statistical tests to identify which gene sets (biological processes) show different levels of activity across different treatment groups. The idea is to identify which biological processes are significantly affected by a certain treatment/condition in a given organism.

Non-model organisms (such as sheep) are not widely studied so gene set membership information is not always readily accessible. This thesis work utilizes two microarray studies involving sheep to provide researchers with working examples of …


Linking Form And Process In Braided Rivers Using Physical And Numerical Models, Alan Kasprak May 2015

Linking Form And Process In Braided Rivers Using Physical And Numerical Models, Alan Kasprak

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Braided rivers are characterized by their dynamic nature, and are often significantly reshaped during each flood capable of transporting sediment. Over time, they adjust in response to the frequency and magnitude of floods, along with the amount of sediment available for bar building. Factors such as climate change, dam construction, or land use alteration that change the amount of sediment or water available to braided rivers may subsequently affect channel form. One avenue toward understanding braided channel evolution is to develop simple relationships between channel form and sediment transport, and extrapolate those relationships over extended timescales. With funding from the …


Relative Toxicity Of Select Dehydropyrrolizidine Alkaloids And Evaluation Of A Heterozygous P53 Knockout Mouse Model For Dehydropyrrolizidine Alkaloid Induced Carcinogenesis, Ammon W. Brown May 2015

Relative Toxicity Of Select Dehydropyrrolizidine Alkaloids And Evaluation Of A Heterozygous P53 Knockout Mouse Model For Dehydropyrrolizidine Alkaloid Induced Carcinogenesis, Ammon W. Brown

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Dehydropyrrolizidine alkaloids (DHPAs) are toxins produced by approximately 3% of the world’s flowering plants that can be present naturally or as contaminants in animal feed and the human food supply. Many of these compounds have been determined to cause cancer in animals and probably also cause cancer in humans. Due to the difficulty in obtaining sufficient amounts of pure DHPAs most toxicity research has been done via injection of a small amount into the abdomen of a rodent, although natural exposure is exclusively oral. For the same reason, cancer research is limited to a handful of the hundreds of known …