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Unified Model Of Charge Transport In Insulating Polymeric Materials, Alec Sim Dec 2013

Unified Model Of Charge Transport In Insulating Polymeric Materials, Alec Sim

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Charge transport, charging, and subsequent electrostatic discharge due to interactions with the space environment are primary concerns of spacecraft designers. Developing a physical understanding of the interactions of charge with the multitude of materials that spacecraft are composed of is a critical step in understanding and mitigating both short-term and long-term spacecraft degradation. In particular, the study of charge transport in highly insulating materials is critical as they store charge longer, with higher capacity, and with greater destructive capability than other materials.

The Utah State University Materials Physics Group, with the funding of the NASA James Webb Space Telescope project …


Alluvial Geochronology And Watershed Analysis Of The Golo River, Northeastern Corsica, France, Emilee M. Skyles Dec 2013

Alluvial Geochronology And Watershed Analysis Of The Golo River, Northeastern Corsica, France, Emilee M. Skyles

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Golo River in Corsica, France, is a short, steep river (~95 km, 2706 m relief) in the Western Mediterranean with formerly glaciated headwaters. The small size and location of the Golo River make this system ideal for observing the influence of climate and sea-level change on river dynamics over the 100,000 years. A rapidly advancing dating technique, optically stimulated luminescence, was utilized to determine the timing of these river deposits on the coastal plain in order to frame them in the context of previous glacial and interglacial episodes. Climate fluctuations in the headwaters supplied the vast majority of sediment …


Substrate Binding And Reduction Mechanism Of Molybdenum Nitrogenase, Zhiyong Yang Dec 2013

Substrate Binding And Reduction Mechanism Of Molybdenum Nitrogenase, Zhiyong Yang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As a key constituent of proteins, nucleic acids, and other biomolecules, nitrogen is essential to all living organisms including human beings. Dinitrogen represents the largest pool of nitrogen, about 79% of the Earth’s atmosphere, yet it is unusable by most living organisms due to its inertness. There are two ways to fix this inert dinitrogen to usable ammonia. One is the industrial Haber-Bosch process, which needs to be conducted at high temperature and pressure. This process uses a lot of the non-renewable fossil fuel as the energy source. The other major pathway is the biological nitrogen fixation carried out by …


Effective Graph-Based Content--Based Image Retrieval Systems For Large-Scale And Small-Scale Image Databases, Ran Chang Dec 2013

Effective Graph-Based Content--Based Image Retrieval Systems For Large-Scale And Small-Scale Image Databases, Ran Chang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Digital imaging was a great invention in the last century. Since digital cameras became popular in the public, a large amount of digital images emerged in the late of the twentieth century. How to manage the huge amount of images and find desired images among them became an urgent issue during the same period.

Techniques of retrieving a desired image are generally categorized into two basic classes. One relies on text-based key words to retrieve desired images in the image
database. The other one relies on image-based queries to retrieve desired images in the image database. The second technique is …


Mechanisms Of Vegetation-Induced Channel Narrowing On An Unregulated Canyon-Bound River, Rebecca Blanche Manners Aug 2013

Mechanisms Of Vegetation-Induced Channel Narrowing On An Unregulated Canyon-Bound River, Rebecca Blanche Manners

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The accurate prediction of river channel width remains a fundamental area of investigation in the field of geomorphology. River managers and scientists are interested in understanding how a channel will respond to environmental perturbations such as altered runoff patterns from climate change, a new dam, or a pulse of sediment from a landslide. Increasingly, studies that focus on this question acknowledge the importance of accounting for the vegetation that lines the river banks. For this dissertation, I strove to identify some of the primary ways by which vegetation affects channel width.

At a fundamental level, vegetation influences the size of …


Modeling Habitat Use Of A Fringe Greater Sage-Grouse Population At Multiple Spatial Scales, Anya Cheyenne Burnett Aug 2013

Modeling Habitat Use Of A Fringe Greater Sage-Grouse Population At Multiple Spatial Scales, Anya Cheyenne Burnett

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Greater sage-grouse (Centrocercus urophasianus; hereafter sage-grouse) are a prominent bird species of sagebrush-dominated landscapes across the western United States. Over the past 15 years, sage-grouse have gained international attention due to decreasing population trends despite management efforts. In 2010 the U.S. Fish and Wildlife Service designated this species as warranted for listing under the Endangered Species Act, but the listing was precluded by other species at higher conservation risk. Habitat loss, degradation, and fragmentation have been implicated as primary sources of declines in sage-grouse distribution and abundance. The Bald Hills population in southwestern Utah occupies an area with …


Two Scenes From Utah's Stratigraphic Record: Neoproterozoic Snowball Earth, Before And After, Dawn Schmidli Hayes Aug 2013

Two Scenes From Utah's Stratigraphic Record: Neoproterozoic Snowball Earth, Before And After, Dawn Schmidli Hayes

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research is focused on rock units deposited in northern Utah before and after global glacial events of unprecedented magnitude, commonly referred to as
“Snowball Earth” glaciations. The rock units deposited prior to the beginning of these glaciations (~770 to 740 million years ago) include the Uinta Mountain Group in Utah’s Uinta Mountains. Rock units deposited after the glaciations (either ~665 or ~635 million years ago) include parts of the Kelley Canyon Formation on Antelope Island in the Great Salt Lake. These rocks, deposited in shallow ocean environments, record the history of life and ocean chemistry just before and after …


Formation, Deformation, And Incision Of Colorado River Terraces Upstream Of Moab, Utah, Andrew P. Jochems Aug 2013

Formation, Deformation, And Incision Of Colorado River Terraces Upstream Of Moab, Utah, Andrew P. Jochems

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The history of rivers is laid down as sediment in all landscapes, typically as a function of climate, geologic structures, and/or changes in sea level. When a river abandons its floodplain, this sediment collectively constitutes a landform called a fluvial terrace. Terraces are used to unlock prior characteristics of a river flowing through a given area at both local and regional scales. Dating terrace sediment allows comparison to known changes in climate and geologic deformation, two significant controls on the hydraulics of rivers and the deposition of their sediment loads.

The importance of terraces lies in their utility as markers …


A Middle To Late Holocene Record Of Arroyo Cut-Fill Events In Kitchen Corral Wash, Southern Utah, William M. Huff May 2013

A Middle To Late Holocene Record Of Arroyo Cut-Fill Events In Kitchen Corral Wash, Southern Utah, William M. Huff

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Arroyos are steeply entrenched channels that form by incision into weakly consolidated valley-fill alluvium. This study attempts to offers clues into the processes behind their formation by dating arroyo sediments using luminescence and radiocarbon techniques. The importance of understanding arroyo formation is due to a possible linkage with decadal to centennial-scale climate fluctuations. In the 1800s and early 1900s, many of the shallow, perennial streams throughout southern Utah that used for a variety of agricultural and domestic uses were incised up to ~30 m into their alluvium by frequent and high-magnitude flood events. The economical and ecological effects of these …


Constraining Ice Advance And Linkages To Paleoclimate Of Two Glacial Systems In The Olympic Mountains, Washington And The Southern Alps, New Zealand, Cianna E. Wyshnytzky May 2013

Constraining Ice Advance And Linkages To Paleoclimate Of Two Glacial Systems In The Olympic Mountains, Washington And The Southern Alps, New Zealand, Cianna E. Wyshnytzky

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis investigates glacial sediments in the South Fork Hoh River Valley, Washington and the Lake Hawea Valley, New Zealand that were deposited during the last glacial period. Research objectives were to reconstruct the style and timing of glacier advance and retreat in both areas and to assess the viability of luminescence dating of sediments in glacial environments.

Glaciers are influenced primarily by temperature and precipitation. Valley glaciers, like those in the Olympics Mountains and Southern Alps, are thought to respond relatively rapidly to climate fluctuations in comparison to continental ice sheets. Understanding how these glacial systems responded to past …


Empirical Properties Of Functional Regression Models And Application To High-Frequency Financial Data, Xi Zhang May 2013

Empirical Properties Of Functional Regression Models And Application To High-Frequency Financial Data, Xi Zhang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Functional data analysis (FDA) has grown into a substantial field of statistical research, with new methodology, numerous useful applications and interesting novel theoretical developments. My dissertation focuses on the empirical properties of functional regression models and their application to financial data. We start from testing the empirical properties of forecasts with the functional autoregressive models based on simulated and real data. We define intraday returns and consider their prediction from such returns on a market index. This is an extension to intraday data of the Capital Asset Pricing model. Finally we investigate multifactor functional models and assess their suitability for …


The Effects Of Abstraction On Best Nblock First Search, Justin R. Redd May 2013

The Effects Of Abstraction On Best Nblock First Search, Justin R. Redd

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Search is an important aspect of Artificial Intelligence. Efficiently searching for solutions to large problems is important. One way to scale search large in problems quickly is to divide the work between multiple processors. There are many ways to divide this work using abstractions. This thesis examines the previous way this has been done in the past and introduces other ways to more efficiently divide the work and search in parallel.


Dot Product Graphs And Their Applications To Ecology, Sean Bailey May 2013

Dot Product Graphs And Their Applications To Ecology, Sean Bailey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

We will introduce a new tool to visualize the comparison between different birds. This tool will allow users to use any number of measurable traits to see relationships between different birds, both individually and collectively.


Oxidative Aliphatic Carbon-Carbon Bond Cleavage Reactions, Caleb J. Allpress May 2013

Oxidative Aliphatic Carbon-Carbon Bond Cleavage Reactions, Caleb J. Allpress

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The work presented in this dissertation has focused on the activation and cleavage of chemical bonds between two carbon atoms. The selective oxidative activation of carbon-carbon bonds is important due to potential applications in the utilization of biomass for fuel production, applications in wastewater treatment and bioremediation, and in developing new reactions for organic synthesis of fine chemicals including pharmaceuticals. Ideally these reactions would be carried out with high atom economy at low temperatures and pressures, and using earth-abundant elements as reagents and catalysts. With these points in mind, nature provides an ideal model framework, carrying out its chemistry at …


Evaluation Of The Geothermal Potential Of The Snake River Plain, Idaho, Based On Three Exploration Holes, Thomas G. Freeman May 2013

Evaluation Of The Geothermal Potential Of The Snake River Plain, Idaho, Based On Three Exploration Holes, Thomas G. Freeman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The work in this thesis was based on analyzing water samples collected from three exploratory boreholes drilled during Project Hotspot. The water samples were analyzed for their chemical properties. The chemical properties of the water samples were used as a basis for further analysis.

Geophysical logs, mainly temperature logs, were also analyzed for this project. Temperature logs measure temperature in relation to depth within a borehole.

All the analyses were made in order to estimate the geothermal potential of the project areas. The exploratory boreholes were all drilled in different areas and each had unique characteristics. The Mountain Home borehole …


On Mobile Detection And Localization Of Skewed Nutrition Facts Tables, Christopher Blay May 2013

On Mobile Detection And Localization Of Skewed Nutrition Facts Tables, Christopher Blay

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Computer Science Assistive Technology Laboratory (CSATL) at Utah State University has a long history of research in visually impaired grocery shopping tech. CSATL’s ShopMobile II introduced nutrition facts table (NFT) analysis but only with perfectly aligned and square input images.

A new method which detects and localizes NFTs more quickly and from rotated or non-square images has been released and is slated for integration with ShopMobile II to improve this feature substantially. This is great news for the estimated 3.6 million adults in the United States having visual impairment or blindness and also opens the doors to other applications …


Earthquake Petrology: Linking Fault-Related Deformation To The Earthquake Cycle, Mitchell R. Prante May 2013

Earthquake Petrology: Linking Fault-Related Deformation To The Earthquake Cycle, Mitchell R. Prante

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Faults have a controlling influence on a variety of geologic processes including fluid flow, the mechanical behavior of the crust, and seismicity. The geologic sciences have long recognized that faults generate earthquakes; however, few indicators of ancient earthquakes exist in fault-zones. This dissertation documents several indicators for the preservation of ancient earthquakes in fault-zones including frictional melt (pseudotachylyte), highly-polished fault slip surfaces, and hydrothermal alteration.

These deformation products result from rapid generation of frictional heat during earthquakes. This dissertation also focuses on the seismic potential of continental low-angle normal faults (LANF). We document the preservation of voluminous pseudotachylyte along a …


Weyl Gravity As A Gauge Theory, Juan Teancum Trujillo May 2013

Weyl Gravity As A Gauge Theory, Juan Teancum Trujillo

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A gauge theory is a theory in which the governing functional, known as the action, remains invariant under a continuous group of local transformations that form its symmetry. Each of the known fundamental interactions in the universe, such as electricity and magnetism, can be explained as arising from a particular gauge theory. Gravitation is no exception. Just as calculus can be used to find the value of a variable that maximizes or minimizes a function, calculus of variations can be used to find the equations, known as the field equations, that extremize the action, and these are the main equations …


Concurrent Neurological And Behavioral Assessment Of Number Line Estimation Performance In Children And Adults, Joseph Michael Baker May 2013

Concurrent Neurological And Behavioral Assessment Of Number Line Estimation Performance In Children And Adults, Joseph Michael Baker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Understanding the brain’s response to common math-learning activities may help improve math education. For example, by imaging the brains of typically developing children and adults throughout a number line estimation task, it is possible to establish a baseline of what “typical” brains do in such situations. Thus, comparisons may be made to determine the degree to which brain functioning differs between typical and atypical math learners. Moreover, by identifying methods that may increase the brain’s response to real-world math activities, it may be possible to improve the math learning process for typical and atypical learners alike.

Brain imaging devices such …


The Chain-Link Fence Model: A Framework For Creating Security Procedures, Robert F. Houghton May 2013

The Chain-Link Fence Model: A Framework For Creating Security Procedures, Robert F. Houghton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Information technology security professionals are facing an ever growing threat to the networks that they defend. The process for creating procedures to help stem this threat is very difficult for security professionals. The Chain-Link Fence Model helps security professionals by guiding them through the process of creating and implementing new security procedures.


Southward Continuation Of The San Jacinto Fault Zone Through And Beneath The Extra And Elmore Ranch Left-Lateral Fault Arrays, Southern California, Steven Jesse Thornock May 2013

Southward Continuation Of The San Jacinto Fault Zone Through And Beneath The Extra And Elmore Ranch Left-Lateral Fault Arrays, Southern California, Steven Jesse Thornock

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Clark fault is a significant fault within the southern San Andreas fault system. The Clark fault abruptly ends where it intersects a second, smaller fault that crosses it called the Extra fault zone. In this study we investigate the possibility of the Clark fault continuing beneath and beyond the Extra fault zone. Based on field mapping and other geological data that we present, we determine that the Clark fault continues below the Extra fault and is not evident on the surface. Over time, earthquake slip along the Clark fault has caused the Extra fault zone to rotate in a …


Existence And Multiplicity Results On Standing Wave Solutions Of Some Coupled Nonlinear Schrodinger Equations, Rushun Tian May 2013

Existence And Multiplicity Results On Standing Wave Solutions Of Some Coupled Nonlinear Schrodinger Equations, Rushun Tian

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Coupled nonlinear Schrodinger equations (CNLS) govern many physical phenomena, such as nonlinear optics and Bose-Einstein condensates. For their wide applications, many studies have been carried out by physicists, mathematicians and engineers from different respects. In this dissertation, we focused on standing wave solutions, which are of particular interests for their relatively simple form and the important roles they play in studying other wave solutions. We studied the multiplicity of this type of solutions of CNLS via variational methods and bifurcation methods.

Variational methods are useful tools for studying differential equations and systems of differential equations that possess the so-called variational …


Cougar Predation Behavior In North-Central Utah, Dustin L. Mitchell May 2013

Cougar Predation Behavior In North-Central Utah, Dustin L. Mitchell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Today’s ability to apply global positioning systems (GPS) collars to wild animals and track their movements, without inadvertently disrupting their daily routine, is a major benefit to wildlife research. Cougars are carnivorous predators that have been identified as being one of several possible causes for recent mule deer population declines throughout the Western United States. Past cougar predation studies have relied on snow tracking, radio-collar tracking, and modeling techniques to estimate cougar prey use and predation rates. These methods rely heavily on weather conditions, logistical availabilities, and broad assumptions, which have led to a wide range of predation rate estimates. …


Study Of Genes Relating To Degradation Of Aromatic Compounds And Carbon Metabolism In Mycobacterium Sp. Strain Kms, Chun Zhang May 2013

Study Of Genes Relating To Degradation Of Aromatic Compounds And Carbon Metabolism In Mycobacterium Sp. Strain Kms, Chun Zhang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Polycyclic aromatic hydrocarbons are produced from incomplete combustion of organic materials by human or natural activities. These polycyclic aromatic hydrocarbons are classified as pollutants because of their toxic, mutagenic, and carcinogenic characteristics. Mycobacterium sp. strain KMS, isolated from a contaminated soil, grows on the model polycyclic aromatic hydrocarbon, pyrene, with its degradation to water and carbon dioxide. This study locates genes on the chromosome and plasmids of isolate KMS relating to pyrene degradation, elucidates the influence of other carbon sources available in the habitats of isolate KMS on degradation of pyrene, and deduces possible metabolic pathways used by isolate …


A Numerical Algorithm For Simulating Two Species Plasma, Richard F. Datwyler May 2013

A Numerical Algorithm For Simulating Two Species Plasma, Richard F. Datwyler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In our ever-growing technology-dependent society, a great need for cleaner, more lucrative energy sources is being sought out. Nuclear fission power plants have been used to help provide energy for many years now. More recently, fusion test reactors have been built and planned as another means to fill the energy quota. A large part of understanding the fundamental principles in a fusion reactor focuses on the principles of plasma physics. This topic of plasma physics has been studied for many decades and much progress has been made in its understanding.

More recently, computers have become larger and faster allowing for …


Statistical Algorithms For Optimal Experimental Design With Correlated Observations, Chang Li May 2013

Statistical Algorithms For Optimal Experimental Design With Correlated Observations, Chang Li

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The first part of my dissertation demonstrates that a modified simulated annealing algorithm can successfully determine highly efficient D-optimal designs for second order polynomial regression for a variety of correlated error structures.

In the second part, I solved weak universal optimal block designs for the nearest neighbor correlation structure and multiple block sizes, for the hub correlation structure with any block size, and for circulant correlation with odd block size.

In the third part, we propose an improved Particle Swarm Optimization (PSO) algorithm with time varying parameters. Then combining the theorem of decision making and PSO, we innovated nested PSO …


Knowledge Extraction In Video Through The Interaction Analysis Of Activities, Omar Ulises Florez May 2013

Knowledge Extraction In Video Through The Interaction Analysis Of Activities, Omar Ulises Florez

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A video is a growing stream of unstructured data that significantly increases the amount of information transmitted and stored on the Internet. For example, every minute YouTube users upload 72 GB of information. Some of the best applications for video analysis include the monitoring of activities in defense and security scenarios such as the autonomous planes that collect video and images at reduced risk and the surveillance cameras in public places like traffic lights, airports, and schools.

Some of the challenges in the analysis of video correspond to implement complex operations such as searching of activities, understanding of scenes, and …


Enhanced Structural Support Of Metal Sites As Nodes In Metal-Organic Frameworks Compared To Metal Complexes, Sanjit Das May 2013

Enhanced Structural Support Of Metal Sites As Nodes In Metal-Organic Frameworks Compared To Metal Complexes, Sanjit Das

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Crystalline porous materials have gained long-standing interest for their application in gas storage, separation and catalysis. These materials have been useful for domestic, scientific and industrial purposes for many decades. Zeolites are a well known example of such materials.

Metal-organic frameworks are a new class of crystalline porous materials. They have many advantages over the more widely known zeolites. Though metal-organic frameworks are relatively new, their basic structure, known as the secondary building unit, very closely resembles the structure of metal complexes. Such metal complexes have been characterized in chemistry for more than a century.

Chemical catalysis is a process …


Fault Seal Analysis For Co2 Storage: Fault Zone Architecture, Fault Permeability, And Fluid Migration Pathways In Exposed Analogs In Southeastern Utah, David J. Richey May 2013

Fault Seal Analysis For Co2 Storage: Fault Zone Architecture, Fault Permeability, And Fluid Migration Pathways In Exposed Analogs In Southeastern Utah, David J. Richey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Anthropogenic carbon dioxide (CO2) primarily resulting from the combustion of fossil fuels can be captured and stored by injection into underground porous sandstone reservoirs. This process has been proposed as a method for reducing greenhouse gas emissions that contribute to global warming. Two of the major risks associated with this technology include: 1) upwards migration and leakage of injected fluids along natural fault and fracture networks, and 2) possible induced seismicity (earthquakes) resulting from increasing the pressure in reservoirs and along existing faults.

We use geologic field mapping, petrographic analysis, characterization of the fault zone, analysis of altered …


Eyes-Free Vision-Based Scanning Of Aligned Barcodes And Information Extraction From Aligned Nutrition Tables, Aliasgar Kutiyanawala May 2013

Eyes-Free Vision-Based Scanning Of Aligned Barcodes And Information Extraction From Aligned Nutrition Tables, Aliasgar Kutiyanawala

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Independent grocery shopping is one of the biggest challenges faced by visually impaired (VI) individuals. VI individuals may be able to get to a store on their own by using public transportation or by walking but are unable to shop there independently. Some of the problems that they face after getting to the store include long wait times to get an employee to assist them or getting a store employee who is not familiar with the store layout, gets irritated with long searches, or does not possess the required English skills. These problems ultimately result in VI shoppers having to …