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All Graduate Theses and Dissertations

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Full-Text Articles in Physical Sciences and Mathematics

Juxtaposition At 45 Km Of Temperatures From Rayleigh-Scatter Lidar And Reanalysis Models, David K. Moser May 2019

Juxtaposition At 45 Km Of Temperatures From Rayleigh-Scatter Lidar And Reanalysis Models, David K. Moser

All Graduate Theses and Dissertations

Weather and climate forecasts are almost exclusively produced by computer models, which use atmospheric measurements as starting points. It is a well-known and joked-about fact that model predictions can be incorrect at times. One of the reasons this happens is due to gaps in our knowledge of atmospheric conditions in areas where measurements don’t often taken place, such as the mesosphere, which stretches from roughly 45-90 km altitude.

A lidar is a device that can shoot out short bursts of laser light to measure things such as atmospheric thickness at a distance. From this information one can then derive ...


Multi-Resolution Analysis Using Wavelet Basis Conditioned On Homogenization, Abibat Adebisi Lasisi Dec 2018

Multi-Resolution Analysis Using Wavelet Basis Conditioned On Homogenization, Abibat Adebisi Lasisi

All Graduate Theses and Dissertations

This dissertation considers an approximation strategy using a wavelet reconstruction scheme for solving elliptic problems. The foci of the work are on (1) the approximate solution of differential equations using multiresolution analysis based on wavelet transforms and (2) the homogenization process for solving one and two-dimensional problems, to understand the solutions of second order elliptic problems. We employed homogenization to compute the average formula for permeability in a porous medium. The structure of the associated multiresolution analysis allows for the reconstruction of the approximate solution of the primary variable in the elliptic equation. Using a one-dimensional wavelet reconstruction algorithm proposed ...


Surviving A Civil War: Expanding The Scope Of Survival Analysis In Political Science, Andrew B. Whetten Dec 2018

Surviving A Civil War: Expanding The Scope Of Survival Analysis In Political Science, Andrew B. Whetten

All Graduate Theses and Dissertations

Survival Analysis in the context of Political Science is frequently used to study the duration of agreements, political party influence, wars, senator term lengths, etc. This paper surveys a collection of methods implemented on a modified version of the Power-Sharing Event Dataset (which documents civil war peace agreement durations in the Post-Cold War era) in order to identify the research questions that are optimally addressed by each method. A primary comparison will be made between a Cox Proportional Hazards Model using some advanced capabilities in the glmnet package, a Survival Random Forest Model, and a Survival SVM. En route to ...


Running The Cañons Of The Rio Grande: Part 2 Boquillas Canyon, Texas And Coahuila, Todd L. Blythe Dec 2018

Running The Cañons Of The Rio Grande: Part 2 Boquillas Canyon, Texas And Coahuila, Todd L. Blythe

All Graduate Theses and Dissertations

In 1899, Robert T. Hill led the first scientific exploration of the remote segment of the Rio Grande known as the Big Bend. Hill’s observations from this expedition were published in an article titled “Running the Cañons of the Rio Grande.” At the time of Hill’s expedition, the stream flow of the Rio Grande was largely depleted by water development in the upstream portions of the basin. The continued overallocation of the Rio Grande has led to the degradation of aquatic ecosystems in the Big Bend, one of North America’s largest transboundary protected areas, such that management ...


New Ca-Id-Tims Detrital Zircon Constraints On Middle Neoproterozoic Sedimentary Successions, Southwestern United States, Abigail R. Bullard Dec 2018

New Ca-Id-Tims Detrital Zircon Constraints On Middle Neoproterozoic Sedimentary Successions, Southwestern United States, Abigail R. Bullard

All Graduate Theses and Dissertations

Three related sedimentary successions located in Arizona, Utah, and California were deposited in basins on proto-North America during the early rifting of Rodinia (~780 Mya). Previous detrital zircon U-Pb maximum ages for the units are inexact, making it difficult to piece together what happened at this point in Earth history.

We report better maximum age constraints on these units obtained by subjecting detrital zircons to high-precision CA-ID-TIMS analysis, which provide more exact 206 Pb/238U ages. These new data significantly improve the precision for the base of the ChUMP units, with an average age of 775. 63 ± 0.27 Ma ...


Climate Change Perceptions And Adaptation Among Small-Scale Farmers In Uganda: A Community-Based Participatory Approach, Thomas Derr Dec 2018

Climate Change Perceptions And Adaptation Among Small-Scale Farmers In Uganda: A Community-Based Participatory Approach, Thomas Derr

All Graduate Theses and Dissertations

Climate change in the East African country of Uganda is causing severe variations in the once predictable seasonal weather patterns that farmers had come to depend on. This, in combination with social and economic challenges, has significantly increased the vulnerability of farmers who make up the majority of Uganda’s population. Previous knowledge and observations suggest that Ugandan farmers may be reluctant or slow to change their practices in response to the changing climate. Strategies are therefore needed to identify challenges and sustainable solutions. This research used qualitative data collection methods known as participatory rural appraisal (PRA) and participatory action ...


Mesospheric Gravity Wave Climatology And Variances Over The Andes Mountains, Jonathan Rich Pugmire Dec 2018

Mesospheric Gravity Wave Climatology And Variances Over The Andes Mountains, Jonathan Rich Pugmire

All Graduate Theses and Dissertations

Look up! Travelling over your head in the air are waves. They are present all the time in the atmosphere all over the Earth. Now imagine throwing a small rock in a pond and watching the ripples spread out around it. The same thing happens in the atmosphere except the rock is a thunderstorm, the wind blowing over a mountain, or another disturbance. As the wave (known as a gravity wave) travels upwards the thinning air allows the wave to grow larger and larger. Eventually the gravity wave gets too large – and like waves on the beach – it crashes causing ...


An Examination Of What Motivates Utah Residents To Adopt The Practice Of Rainwater Harvesting, D. Wayne Honaker Dec 2018

An Examination Of What Motivates Utah Residents To Adopt The Practice Of Rainwater Harvesting, D. Wayne Honaker

All Graduate Theses and Dissertations

Although most of the earth is covered in water, a very limited amount of that water is fresh water, which is essential to our survival. Therefore, it is imperative that we do all that is possible to conserve and protect our extremely limited water resources, especially in arid regions such as the American West. While there are many ways and means to protecting and preserving our water resources, this thesis focuses on the strategy of rainwater harvesting (RWH) as it is done throughout the state of Utah. RWH is defined as taking the precipitation that falls on our built structures ...


Quantum Mechanical Studies Of N-H···N Hydrogen Bonding In Acetamide Derivatives And Amino Acids, Sandra J. Lundell Dec 2018

Quantum Mechanical Studies Of N-H···N Hydrogen Bonding In Acetamide Derivatives And Amino Acids, Sandra J. Lundell

All Graduate Theses and Dissertations

Proteins are made of vast chains of amino acids that twist and fold into intricate designs. These structures are held in place by networks of noncovalent interactions. One of these, the hydrogen bond, forms bridges between adjacent pieces of the protein chain and is one of the most important contributors to the shape and stability of proteins. Hydrogen bonds come in all shapes and sizes and a full understanding of these not only aids in our understanding of proteins in general but can bridge the gap to finding cures to many protein-related diseases, such as sickle-cell anemia. The primary aim ...


Improving Accuracy Of The Edgebox Approach, Kamna Yadav Dec 2018

Improving Accuracy Of The Edgebox Approach, Kamna Yadav

All Graduate Theses and Dissertations

Object region detection plays a vital role in many domains ranging from self-driving cars to lane detection, which heavily involves the task of object detection. Improving the performance of object region detection approaches is of great importance and therefore is an active ongoing research in Computer Vision. Traditional sliding window paradigm has been widely used to identify hundreds of thousands of windows (covering different scales, angles, and aspect ratios for objects) before the classification step. However, it is not only computationally expensive but also produces relatively low accuracy in terms of the classifier output by providing many negative samples. Object ...


The Influence Of Mechanical Stratigraphy On Thrust-Ramp Nucleation And Propagation Of Thrust Faults, Sarah S. Wigginton Dec 2018

The Influence Of Mechanical Stratigraphy On Thrust-Ramp Nucleation And Propagation Of Thrust Faults, Sarah S. Wigginton

All Graduate Theses and Dissertations

Our current understanding of thrust fault kinematics predicts that thrust faults nucleate on low angle, weak surfaces before they propagate upward and forms a higher angle ramp. While this classic kinematic and geometric model serves well in some settings, it does not fully consider the observations of footwall deformation beneath some thrust faults. We examine an alternative end-member model of thrust fault formation called “ramp-first” fault formation. This model hypothesizes that in mechanically layered rocks, thrust ramps nucleate in the structurally strong units, and that faults can propagate both upward and downward into weaker units forming folds at both fault ...


Historical Channel Change Caused By A Century Of Flow Alteration On Sixth Water Creek And Diamond Fork River, Ut, Jabari C. Jones Dec 2018

Historical Channel Change Caused By A Century Of Flow Alteration On Sixth Water Creek And Diamond Fork River, Ut, Jabari C. Jones

All Graduate Theses and Dissertations

Changes in the amount of water and sediment that enter a river can change its shape and size. The way that rivers change is affected by a variety of factors, including the size of the sediment in the river, and past changes to the river. The Diamond Fork River in central Utah has been altered by water deliveredfromthe Colorado River system for over a century. Beginning in 1915, water used for irrigation was delivered through a tributary, Sixth Water Creek, with daily summer flows that were much larger than natural flows. This caused drastic change to the rivers, as they ...


Sheaf Theory As A Foundation For Heterogeneous Data Fusion, Seyed M-H Mansourbeigi Dec 2018

Sheaf Theory As A Foundation For Heterogeneous Data Fusion, Seyed M-H Mansourbeigi

All Graduate Theses and Dissertations

A major impediment to scientific progress in many fields is the inability to make sense of the huge amounts of data that have been collected via experiment or computer simulation. This dissertation provides tools to visualize, represent, and analyze the collection of sensors and data all at once in a single combinatorial geometric object. Encoding and translating heterogeneous data into common language are modeled by supporting objects. In this methodology, the behavior of the system based on the detection of noise in the system, possible failure in data exchange and recognition of the redundant or complimentary sensors are studied via ...


The Development Of Hydrodynamic And Kinetic Models For The Plasmasphere Refilling Problem Following A Geomagnetic Storm, Kausik Chatterjee Dec 2018

The Development Of Hydrodynamic And Kinetic Models For The Plasmasphere Refilling Problem Following A Geomagnetic Storm, Kausik Chatterjee

All Graduate Theses and Dissertations

The objective of this dissertation is the development of computer simulation-based models for the modeling of upper ionosphere, starting from the first principles. The models were validated by exact analytical benchmarks and are seen to be consistent with experimentally obtained results. This area of research has significant implications in the area of global communication. In addition, these models would lead to a better understanding of the physical processes taking place in the upper ionosphere.


Sensitivity Of The Opal Instrument For Gravity Wave Detection, Kenneth I. Zia Dec 2018

Sensitivity Of The Opal Instrument For Gravity Wave Detection, Kenneth I. Zia

All Graduate Theses and Dissertations

Knowing what goes on in the upper atmosphere (∼80-140 km) is very important to the space science community. There are several competing forces that influence the temperature and densities of neutral molecules in that region. OPAL (Optical Profiling of the Atmospheric Limb) is funded by the National Science Foundation (NSF) to measure the temperature there using light from oxygen molecules (∼760 nm). To accomplish this,OPAL is built into a CubeSat (a satellite the size of a loaf of bread) to be launched from the International Space Station (ISS) at an altitude of about 400 km. This vantage point is ...


Energy And Risk: Discourse, Framing, And Content, Temis Gardner Taylor Dec 2018

Energy And Risk: Discourse, Framing, And Content, Temis Gardner Taylor

All Graduate Theses and Dissertations

This research examined how people communicate and create knowledge about energy-related risks. Analysis of the discourse, frames, and content surrounding unconventional energy policy and development in the Western United States was conducted using three case studies. The results contribute to an understanding of energy-related risk perceptions in social and historical contexts.

Discourses contained in newspapers and public comments to the Bureau of Land Management presented arguments on the basis of risks to the environment; climate; human health and safety; jobs and economic prosperity; property rights; and local governments. Governments were seen as risks when they were perceived to allow misuse ...


Comparing Performance Of Gene Set Test Methods Using Biologically Relevant Simulated Data, Richard M. Lambert Dec 2018

Comparing Performance Of Gene Set Test Methods Using Biologically Relevant Simulated Data, Richard M. Lambert

All Graduate Theses and Dissertations

Today we know that there are many genetically driven diseases and health conditions.These problems often manifest only when a set of genes are either active or inactive. Recent technology allows us to measure the activity level of genes in cells, which we call gene expression. It is of great interest to society to be able to statistically compare the gene expression of a large number of genes between two or more groups. For example, we may want to compare the gene expression of a group of cancer patients with a group of non-cancer patients to better understand the genetic ...


“I Really Don’T Look For Certifications, It All Has To Do With Personal Relationships”: The Construction Of A Meat Philosophy And Innovation Adoption By Culinary Professionals In The Rocky Mountain Region, Kailie B. Leggett Dec 2018

“I Really Don’T Look For Certifications, It All Has To Do With Personal Relationships”: The Construction Of A Meat Philosophy And Innovation Adoption By Culinary Professionals In The Rocky Mountain Region, Kailie B. Leggett

All Graduate Theses and Dissertations

Demand for new methods of beef production is rising due to concern over potential impacts on human health, animal welfare, and the environment. Researchers at Utah State University have developed a method of beef production from cattle finished on tannin-containing legume forages in the Rocky Mountain Region in order to address those concerns. To ensure success of this product, the demand and marketability needed to be assessed. Food values addressed through new production standards and certifications are communicated through labeling by culinary professionals in the kitchen and behind service counters. This research study utilized qualitative methods to understand how culinary ...


Inorganic Electrocatalysts For Innovative Water Splitting And Organic Upgrading, Nan Jiang Dec 2018

Inorganic Electrocatalysts For Innovative Water Splitting And Organic Upgrading, Nan Jiang

All Graduate Theses and Dissertations

The booming worldwide demand for energy and the increasing concerns about global warming due to fossil fuel consumption have urged the development of techniques for storing and converting renewable and clean energy resources. Electrocatlytic or photoelectrocatalytic water splitting to generate green energy carrier H2 with sustainable energy input, like solar, has been regarded as an attractive strategy for carbon-neutral energy needs. However, the sluggish kinetics for both half reactions (HER and OER), high overpotentials and thermodynamic requirements, and H2 and O2 gas crossover have been regarded as the major challenges, which limit its widespread application.

On account ...


Carbon Monoxide On Demand: Light-Induced Co Release Of Flavonols, Stacey N. Anderson Dec 2018

Carbon Monoxide On Demand: Light-Induced Co Release Of Flavonols, Stacey N. Anderson

All Graduate Theses and Dissertations

Carbon monoxide (CO) is an extremely useful molecule with applications in industrial manufacturing, synthetic procedures as a C1 building block, and as a potential pharmaceutical to produce anti-inflammatory effects and vasodilation. However, the toxicity associated with CO has prevented its full utilization. In order to safely handle CO, compounds and molecules have been developed that act as storage materials for the gas. Ideal storage platforms only release CO upon stimulation via a trigger. Light activation is the most desirable trigger as it can be regulated in terms of the intensity and the wavelength of light used. The majority of light-induced ...


Examining Teacher Perceptions When Utilizing Volunteers In School-Based Agricultural Education Programs, Ashley B. Cromer Dec 2018

Examining Teacher Perceptions When Utilizing Volunteers In School-Based Agricultural Education Programs, Ashley B. Cromer

All Graduate Theses and Dissertations

There has been little research conducted related to how school-based agricultural (SBAE) teachers perceive the utilization of volunteers in the classroom. The United States is facing a shortage of SBAE teachers, and with turnover rates that are not sustainable, solutions for support and reduction of the SBAE teachers’ workload must be sought with diligence. There is potential for volunteers to reduce some of the responsibilities that the SBAE teacher is faced with. The purposes of this study are to determine the demographic characteristics of the volunteers being utilized and of the SBAE teachers, determine the perceived benefits, barriers and beliefs ...


The Power Law Distribution Of Agricultural Land Size, Lauren Chamberlain Dec 2018

The Power Law Distribution Of Agricultural Land Size, Lauren Chamberlain

All Graduate Theses and Dissertations

This paper demonstrates that the distribution of county level agricultural land size in the United States is best described by a power-law distribution, a distribution that displays extremely heavy tails. This indicates that the majority of farmland exists in the upper tail. Our analysis indicates that the top 5% of agricultural counties account for about 25% of agricultural land between 1997-2012. The power-law distribution of farm size has important implications for the design of more efficient regional and national agricultural policies as counties close to the mean account for little of the cumulative distribution of total agricultural land. This has ...


Statistical Methods To Account For Gene-Level Covariates In Normalization Of High-Dimensional Read-Count Data, Lauren Holt Lenz Dec 2018

Statistical Methods To Account For Gene-Level Covariates In Normalization Of High-Dimensional Read-Count Data, Lauren Holt Lenz

All Graduate Theses and Dissertations

The goal of genetic-based cancer research is often to identify which genes behave differently in cancerous and healthy tissue. This difference in behavior, referred to as differential expression, may lead researchers to more targeted preventative care and treatment. One way to measure the expression of genes is though a process called RNA-Seq, that takes physical tissue samples and maps gene products and fragments in the sample back to the gene that created it, resulting in a large read-count matrix with genes in the rows and a column for each sample. The read-counts for tumor and normal samples are then compared ...


Implementing The Use Of Personal Activity Data In An Introductory Statistics Course, Lacy Christensen Aug 2018

Implementing The Use Of Personal Activity Data In An Introductory Statistics Course, Lacy Christensen

All Graduate Theses and Dissertations

Integrating real data into a classroom is one of the recommendations in the Guidelines for Assessment and Instruction in Statistics Education (GAISE) college report which lays out guidelines for an introductory statistics course (Committee, GAISE College Report ASA Revision, 2016). In order to assess the effect of using real data in a classroom, the students received physical activity trackers to wear during an undergraduate introductory statistics course taught in the summer. This tracker, a Fitbit, enabled students to monitor and record their steps, calories, and active time throughout the class. Collecting personal activity data (PAD) creates a large database which ...


Word Recognition In Nutrition Labels With Convolutional Neural Network, Anuj Khasgiwala Aug 2018

Word Recognition In Nutrition Labels With Convolutional Neural Network, Anuj Khasgiwala

All Graduate Theses and Dissertations

Nowadays, everyone is very busy and running around trying to maintain a balance between their work life and family, as the working hours are increasing day by day. In such hassled life people either ignore or do not give enough attention to a healthy diet. An imperative part of a healthy eating routine is the cognizance and maintenance of nourishing data and comprehension of how extraordinary sustenance and nutritious constituents influence our bodies. Besides in the USA, in many other countries, nutritional information is fundamentally passed on to consumers through nutrition labels (NLs) which can be found in all packaged ...


Humans As Sensors: The Influence Of Extreme Heat Vulnerability Factors On Risk Perceptions Across The Contiguous United States, Forrest Scott Schoessow Aug 2018

Humans As Sensors: The Influence Of Extreme Heat Vulnerability Factors On Risk Perceptions Across The Contiguous United States, Forrest Scott Schoessow

All Graduate Theses and Dissertations

Extreme heat events are the deadliest natural hazard in the United States and will continue to get worse in the coming years due to the effects of climate change. As a result, more people will experience deadly heat conditions. This highlights the need for decision-makers to develop better strategies for preventing future losses. How badly individuals are affected by extreme heat depends on many circumstances, such as how high temperatures actually are, weather conditions, and location. For example, a dry 90 °F day in Phoenix is probably more tolerable than a humid 90 °F day in New Orleans for most ...


Brun's 1920 Theorem On Goldbach's Conjecture, James A. Farrugia Aug 2018

Brun's 1920 Theorem On Goldbach's Conjecture, James A. Farrugia

All Graduate Theses and Dissertations

One form of Goldbach’s Conjecture asserts that every even integer greater than 4is the sum of two odd primes. In 1920 Viggo Brun proved that every sufficiently large even number can be written as the sum of two numbers, each having at most nine prime factors. This thesis explains the overarching principles governing the intricate arguments Brun used to prove his result.

Though there do exist accounts of Brun’s methods, those accounts seem to miss the forest for the trees. In contrast, this thesis explains the relatively simple structure underlying Brun’s arguments, deliberately avoiding most of his ...


Teaching Landscape Construction Using Augmented Reality, Arshdeep Singh Aug 2018

Teaching Landscape Construction Using Augmented Reality, Arshdeep Singh

All Graduate Theses and Dissertations

This thesis describes the design, development, and evaluation of an interactive Microsoft HoloLens application that projects landscape models in Augmented Reality. The application was developed using the Unity framework and 3D models created in Sketchup. Using the application, students can not only visualize the models in real space but can also interact with the models using gestures. The students can interact with the models using gaze and air-tap gestures.

Application testing was conducted with 21 students from the Landscape Architecture and Environmental Planning department at Utah State University. To evaluate the application, students completed a usability survey after using the ...


Influence Of Global Atmospheric Circulation Variations On Weather And Climate Extremes, Yen-Heng Lin Aug 2018

Influence Of Global Atmospheric Circulation Variations On Weather And Climate Extremes, Yen-Heng Lin

All Graduate Theses and Dissertations

Global warming and climate change deeply influence weather and climate extremes, causing substantial property damage and loss every year around the world. Given the importance of heating differences between low-latitude and Arctic regions, which produce heat sources and cold sources that each influence global circulations, we investigate three extreme weather events in different regions in order to better understand the possible connections between extreme events and global circulation changes.

This study begins with climate variations in the low-latitude western North Pacific. In early summer, the timing of the wet season has shifted from late May to early June since 1979 ...


Use Of Verified Twitter Accounts During Crisis Events, Kai Anderson Aug 2018

Use Of Verified Twitter Accounts During Crisis Events, Kai Anderson

All Graduate Theses and Dissertations

This thesis reports on the use of verified Twitter accounts during crisis events. Twitter is a social media platform that allows users to broadcast and exchange public text messages and it can be used as a communication tool during crisis events. Verified Twitter accounts are those accounts that Twitter has investigated and found to be genuinely maintained by the claimed owner. Celebrities, public officials, and other well-known persons or companies often seek this account status. The owners of these accounts are likely to provide more accurate or relevant information during a crisis event because they represent a brand, whether themselves ...