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Simulation Of Hypersonic Conditions In A Lab-Scale Environment Using A Hybrid Rocket With Nitrogen Cooling, Joshua R. Sorenson

All Graduate Theses and Dissertations, Fall 2023 to Present

Developing hypersonic vehicles requires testing under extreme heat, airflow, and pressure. Traditional facilities like shock tunnels and arc-heated wind tunnels are costly and slow to set up. This thesis proposes a simpler, low-cost method using a small-scale hybrid rocket motor as a gas generator. The rocket’s hot exhaust is directed onto the front edge of a scaled-down model that represents the nose of a hypersonic vehicle. This creates a realistic flow that matches both the intense heat energy and the pushing force experienced in high-altitude hypersonic flight. The setup allows easy measurement of motor performance, surface pressures, leading-edge temperatures, and …

The Augmented Matching Law, Matias A. Avellaneda

All Graduate Theses and Dissertations, Fall 2023 to Present

Every living organism, including humans, has a finite amount of time available: 24 hours in a day, 365 days in a year, and a certain number of years in its life. At every moment, such an organism will be engaging in one of a multitude of possible activities, such as eating, sleeping, or reading this dissertation. We use the term choice to denote the way in which the organism distributes its time among all these activities, and some of these choice patterns are more beneficial to the organism than others, showcasing the importance of understanding the mechanisms underlying choice. A …

Thermal Rating And Prediction Of Roadway-Embedded Power Electronics For Dynamic Wireless Power Transfer, Forrest D. Nichols

All Graduate Theses and Dissertations, Fall 2023 to Present

Electric vehicles can be charged while driving through wireless charging coils buried in the road surface. To avoid running expensive cables from roadside equipment to each charging pad, the electronics that control the power transfer can also be buried in the road. However, burying these circuit boards removes the ability to cool them with fans or flowing air, so the heat generated during operation must escape naturally into the surrounding road material. If the boards get too hot, components fail—a problem that has already been observed in prototype systems.

Predicting how hot each component on a circuit board will get …

Fibrous Protein Biomaterials: Characterization Of Solitary Bee Silk And Cocoons, And Development Of Recombinant Hagfish And Bee Silk Materials, Oran Wasserman

All Graduate Theses and Dissertations, Fall 2023 to Present

This dissertation explores two complementary aspects of fibrous protein biomaterials: the characterization of understudied naturally occurring solitary bee silk and cocoons; and recombinant expression and biomaterial formation of recombinant hagfish intermediate filaments (rHIF) and a single Osmia lignaria Say (Hymenoptera: Megachilidae) silk protein. Some solitary bee species, which make up about 75% of all bee species, spin silk to construct protective cocoons during development. Despite the importance of silk and cocoons to the solitary bees' life history, their properties remain largely unexplored. This dissertation presents a novel method for isolating and testing individual silk fibers without interfering with the development …

Mining Time Series Shapelets And Association Rules For Solar Flare Prediction, Drew Watson

All Graduate Theses and Dissertations, Fall 2023 to Present

Solar flares are the largest explosions in the solar system; they are caused by changes in the Sun’s magnetic field. Strong solar flares can disrupt power systems, damage satellites, and interfere with radio communication, so improving flare prediction is important. This thesis develops a way to predict severe solar flares while also helping researchers understand why those predictions are made. The approach looks for short patterns in solar magnetic field data that are linked to future flare activity. It then studies how these patterns appear together and in what order they happen over time. By doing this, the research not …

Dbssnet: Dual-Branch Spectral-Spatial Network With Data-Driven And Knowledge-Guided Band Selection For Uav Hyperspectral Wheat Rust Detection, Subin Kim

All Graduate Theses and Dissertations, Fall 2023 to Present

Wheat rust is a serious plant disease that can reduce crop yield and quality. In practice, the disease is often noticed only after visible symptoms appear, when some damage may already be difficult to reverse. This thesis studies whether drone-based imaging can help detect wheat rust earlier and more reliably in field environments. 

Unlike an ordinary color photograph, a hyperspectral image records reflected light at many narrow wavelengths. These measurements can reveal useful information about plant condition, but they are also high dimensional, noisy, and difficult to analyze when only a limited number of labeled field samples are available. To …

Viability Assessment Of Bovine Embryos: A Public Dataset And Deep Learning Baselines, Erfan Khayyati

All Graduate Theses and Dissertations, Fall 2023 to Present

Improving the success rates of cattle breeding is essential for sustainable agriculture, global food security, and high-quality livestock production. Currently, determining whether a lab-grown bovine embryo is healthy enough for a successful pregnancy requires highly trained experts to manually evaluate days of continuous time-lapse video footage. This process is not only incredibly time-consuming but also highly subjective; human reviewers often suffer from visual fatigue when tracking subtle, microscopic cellular changes over a seven-day period, leading to significant disagreement among even top experts on an embryo’s true potential. Furthermore, assessing bovine embryos is notoriously difficult due to their dark, lipid-dense cellular …

Divergent Belowground Strategies Of Savanna Grasses Under Varying Fire Regimes, Abigail C. Schmidt

All Graduate Theses and Dissertations, Fall 2023 to Present

Savannas are unique ecosystems, where trees and grasses live together across the landscape, not quite forming full forests or open grasslands. The ability for trees and grass to coexist is largely the result of widespread disturbances, such as fire. Fire in savannas is largely thought of in how it maintains plants above ground, however, fire also plays a key role in ecosystem and plant processes belowground. First, fire can change how soil nutrients, namely phosphorus, are cycled. Phosphorus is a key nutrient that plants need to function, and plants acquire phosphorus through their roots. Frequent fire can enhance phosphorus availability, …

Secure Agricultural Futures: Re-Defining And -Imagining Agricultural Water Landscapes In The Us West, Britta L. Schumacher

All Graduate Theses and Dissertations, Fall 2023 to Present

Aridity is swiftly becoming the US West’s new normal. As agricultural communities adjust to persistent growing-season scarcity, they find their livelihoods under increasing threat. This points to the urgency of finding paths toward more secure water futures. A piece of this future puzzle includes water (re-)distribution – taking excess from one place and delivering it to another in need. To begin thinking about (re-)distribution, this dissertation engages with three mixed-methods and multiscale studies. The first study pairs county-level data across the 11 westernmost US states with survey data collected from individual producers in Utah to assess past and current trends …

Cash, Cleats, And Carpools: A Multi-Method Investigation Of Resource Allocation In Families With Youth Athletes, Emily Susan Delisle

All Graduate Theses and Dissertations, Fall 2023 to Present

The current thesis is an investigation of time and financial resource allocation in families with youth athletes. Study 1 used a survey questionnaire to explore how the number of athletes in a family impacted the way parents allocated time and financial resources to their oldest child’s youth sport participation. Results indicate that an increase in the number of athletes in a family does not decrease parents’ time or financial commitments to their oldest child’s youth sport participation. Study 2 used interviews to explore how nine parents with multiple athletes experienced the intersecting demands of time, finances, and family life while …

Nicotine Aerosol Self-Administration And Reward Potentiation: Using A Preclinical Model Of Vaping To Investigate The Stimulus-Enhancing Properties Of Nicotine, Kiernan T. Callister

All Graduate Theses and Dissertations, Fall 2023 to Present

Tobacco use is the leading cause of preventable disease and death in the United States and worldwide. Nicotine, the primary component of tobacco, is responsible for the addiction to tobacco and nicotine products, such as Electronic Nicotine Delivery Systems (ENDS). The widespread consumption of these products is motivated by several complex properties of nicotine, such as its ability to increase the rewarding value of stimuli in the environment. Although reward enhancement has been demonstrated via smoking and other forms of nicotine intake, it is unclear if these effects extend to electronic cigarettes. The present study used an animal model of …

Bridging Animal Production And Human Nutrition: How Production Ecology Shapes The Nutritional Quality Of Terrestrial Animal Foods And Human Omega-3 Status, Joseph Vinod Varre

All Graduate Theses and Dissertations, Fall 2023 to Present

The question at the center of this dissertation is simple: does the way food is produced change the quality of the food itself in ways that matter for human health? Across a series of studies on bison meat, eggs, and human dietary intervention, the answer was yes. This work began with a broad look at the modern food system and the nutritional consequences of industrialized diets. In particular, it focused on the growing imbalance between omega-6 and omega-3 fatty acids in the Western diet. This balance matters because omega-3 fats support heart, brain, and immune health, and diets high in …

Bees In The Trap: Leveraging Bumble Bee (Hymenoptera: Apidae: Bombus) Bycatch For Ecological And Genetic Insights, Tori L. Strausser

All Graduate Theses and Dissertations, Fall 2023 to Present

Managers rely on insect monitoring traps to detect insect pests that harm crops and protect food and other agricultural production. However, these traps also capture non-target insects, including bumble bees, raising concerns about whether repeated trapping could harm pollinator populations. This thesis explores whether bees caught as non-targets, also called bycatch, in routine pest monitoring traps can be used to better understand bumble bee populations, and whether traps pose risks to their long-term persistence. Using bumble bees collected from pest surveillance traps placed in crop fields across Utah, this research examined seasonal patterns in body size, timing of capture, and …

Multispecies Weed Detection Using Unmanned Aerial Vehicles And Deep Learning Object Detection Models In Utah Forage Crop Corn Field, Utsav Bhandari

All Graduate Theses and Dissertations, Fall 2023 to Present

Weeds cost global agriculture over $32 billion annually and reduce crop yields by nearly one-third. Current weed control relies heavily on spraying herbicides uniformly across entire fields, leading to herbicide-resistant weeds, environmental harm, and increasing costs for farmers. A smarter approach is detecting weeds from the air and spraying only where they are present. This could dramatically reduce herbicide use while protecting crop yields. This thesis developed a complete system for identifying weeds in corn fields using drone-captured images and artificial intelligence. Working in commercial forage corn fields in Cache Valley, Utah, high-resolution aerial images were collected and used to …

Youth Agricultural Engagement And Its Association With Dietary Diversity, Household Food Insecurity, And Nutritional Status In Southwest Nigeria, Sherif Olasoji

All Graduate Theses and Dissertations, Fall 2023 to Present

Youth remain underserved in nutrition research, policy, and programming despite being an integral part of the food systems. While the nutrition-sensitive agriculture framework has been established, there is limited evidence demonstrating how youth engagement in agriculture can serve as a pathway to improve nutritional outcomes. The study assessed youth agricultural engagement and its association with household dietary diversity, household food insecurity, and nutritional status in southwest Nigeria.

Using a cross-sectional design, data on socio-demographic characteristics, agricultural engagement, dietary diversity, household food insecurity, body mass index, and skin carotenoids were collected from 143 youth aged 15 to 35 from Ekiti, Osun, …

Spatial Prediction Under Uncertainty: Methodological And Computational Advances In Bayesian Maximum Entropy, Kinspride K. Duah

All Graduate Theses and Dissertations, Fall 2023 to Present

Environmental decisions such as infrastructure design, water management, and snow load estimation depend on spatial data that are often incomplete or uncertain. In many cases, measurements are not exact values but ranges, reflecting limitations in data collection methods. Traditional mapping techniques typically simplify these uncertain measurements, which can lead to less accurate predictions. This dissertation introduces improved statistical tools for making spatial predictions when data are uncertain or partially known. By utilizing a framework called Bayesian Maximum Entropy (BME), this research demonstrates how exact measurements and range-based data can be combined in a mathematically consistent way. The work demonstrates that …

Toward Risk-Informed Design Of Supercooling Heat Exchangers: Statistical Inference And Experimental Investigation Of Heterogeneous Ice Nucleation, Daniel B. Gardner

All Graduate Theses and Dissertations, Fall 2023 to Present

Ice-based cooling storage systems can reduce electricity costs and grid strain by making ice during off-peak hours and using it for air conditioning during the day. One promising design works by chilling water below its freezing point as it flows through a heat exchanger, then allowing it to freeze in a separate storage tank. The challenge is that the chilled water can freeze prematurely inside the heat exchanger itself, blocking the flow and shutting the system down. Preventing this unwanted freezing requires understanding how and where ice begins to form on surfaces, a process called nucleation.

This dissertation investigates ice …

Unifying And Expanding Global And Local Variable Importance Methods For Explainable Machine Learning, Kelvyn K. Bladen

All Graduate Theses and Dissertations, Fall 2023 to Present

Machine learning methods are powerful analytical tools used across all scientific disciplines and many other fields of investigation for prediction and inference from diverse data sources. Despite their broad applicability, machine learning methods are often highly complex and difficult to interpret. Developing a greater understanding of which variables most influence a response is essential for increasing the interpretability of these models and supporting informed decision-making. This research focuses on improving how we evaluate the importance of these variables.

One common approach is to shuffle the values of a variable and see how much the model accuracy gets worse. Another approach …

Reciprocal Teaching With Emergent Bilingual Students: Promoting Academic Reading Strategies And Fostering Hope, Lorissa K. Nelson

All Graduate Theses and Dissertations, Fall 2023 to Present

Many students struggle with reading comprehension, and research shows that low literacy skills in a student’s first language can unfortunately lead to lower rates of university program completion, regardless of the language of instruction. When students feel empowered and confident in their ability to achieve their academic goals, they are much more likely to take ownership of their learning. In fact, students who actively demonstrate hopeful thinking and behaviors are consistently more successful in their academic journeys.

My research explores how we can better support these high school students— specifically concurrent enrollment (CE) students—by examining the impact of Reciprocal Teaching. …

Sensitivity Analysis Of A Low-Power Wireless Capacitive Charging System To Inform Thermal Limitations And Battery Size Reduction Potential For Electric Passenger Vehicles, Karmen Teuscher

All Graduate Theses and Dissertations, Fall 2023 to Present

The purpose of using electric vehicles instead of internal combustion engine vehicles that burn gas is to reduce pollutants in the air and potential environmental impacts such as climate change. EVs produce much less air pollutants than ICEVs but manufacturing the EV batteries and the repeated recharging still contributes to the overall air pollution.

Capacitive power transfer systems can wirelessly charge vehicles through the road as they drive along highways or stop at traffic lights. If vehicles charge as they drive, an opportunity opens to reduce the size of the battery while maintaining the same driving range. Reducing the size …

Learning Latent Structure In High-Dimensional Data Via Geometry And Graphs, Haozhe Chen

All Graduate Theses and Dissertations, Fall 2023 to Present

Modern datasets often contain many measured variables for each observation, such as gene-expression levels, brain activity signals, or features in tabular data. These data are also often noisy, meaning that useful patterns are mixed with measurement error or irrelevant variation. Although such datasets can appear complex, they are frequently represented by simpler hidden structures, such as trajectories, clusters, or relationships between observations. This dissertation develops methods for uncovering these hidden structures by learning geometric and graph-based representations directly from data. The first part introduces Functional Information Geometry, which represents local patterns in high-dimensional data using functional features and constructs a …

The Impact Of Early Exposure To Engineering Concepts In The Form Of Family, School Classes, And Stem Extracurriculars On The Long-Term Sense Of Belonging In Undergraduate Women In Engineering, Hannah Lloyd

All Graduate Theses and Dissertations, Fall 2023 to Present

Engineering continues to struggle with the underrepresentation of women, and many women who begin engineering programs report feeling isolated or uncertain about whether they belong. A strong sense of belonging has been linked to greater confidence, persistence, and success in engineering. This study examined how early experiences with engineering before college may influence students' sense of belonging later in their undergraduate engineering programs.

Using survey responses from undergraduate engineering students across the United States, this study explored several types of early exposure to engineering, including family influence, school-based engineering and STEM courses, extracurricular programs such as robotics clubs and engineering …

Advancing Management Strategies For Two Promising Mason Bee Species (Osmia Ribifloris And Osmia Bruneri) For Berry Pollination, Miranda L. Jones

All Graduate Theses and Dissertations, Fall 2023 to Present

Bee management can broadly refer to human manipulation of one or multiple parts of a bee’s lifecycle. Managing honey bees, commonly referred to as beekeeping, is responsible for providing most pollination for global food crops. However, using more than one bee species for crop pollination can have many benefits. Benefits include better crop pollination and insurance in case one bee species underperforms or its population collapses. Some bees within the genus Osmia are already widely managed for crop pollination because their developmental lifecycle allows bee managers to readily deploy pollinating bees in sync with varying crop blooms, and for certain …

Three Essays In Discrete Choice Analysis: Valuation, Attention Level, And Spatial Heterogeneity, Marcelo Pignatari

All Graduate Theses and Dissertations, Fall 2023 to Present

Understanding how people value food labels and environmental goods is essential for designing policies, incentives, and market mechanisms that improve the well-being of the population. In this study, we found that a local label indicating that fruit was produced in Utah makes Utahns value strawberries, gala apples, and dried tart cherries more. An organic label has a similar effect, which is especially strong for dried tart cherries. In contrast, a freshness label only increases value for fruits with a shorter shelf life, such as strawberries. We also found that people who chose to access clarifying information about what these labels …

Visualizing The Phase Space Of Two Interacting Spherical Magnets Via Lagrangian Descriptors, Matthew Pontius

All Graduate Theses and Dissertations, Fall 2023 to Present

This thesis studies the motion of one spherical magnet sliding on another fixed spherical magnet. Although the setup is simple, the resulting motion can range from regular and predictable to chaotic as the energy increases. To understand this behavior, mathematical tools are used to visualize how all possible motions are organized in phase space. These methods reveal patterns such as stable regions, repeating motions, and chaotic trajectories. The results show how order and chaos coexist in this system and provide insight into how small changes in the initial conditions can lead to very different outcomes.

Hidden Symmetries And Higher Dimensional Rotating Black Holes, Luis Fernando Temoche Hurtado

All Graduate Theses and Dissertations, Fall 2023 to Present

A standard approach to probing the dynamics of a physical system is to expose it to an external perturbation—such as an incident wave—and analyze its response after the interaction. Mathematically, this procedure is formulated in terms of differential equations governing the evolution of the perturbation.

In the context of black hole physics, an analogous strategy can be employed by studying the response of the event horizon to external perturbations. The differential equations describing these interactions are often invariant under nontrivial transformations, revealing hidden symmetries that help explain distinctive features of higher-dimensional black holes.

By exploiting these hidden symmetries in the …

Evolving Roles: School Counselors Addressing Mental Health In Pk-12 Education, Evin Daines

All Graduate Theses and Dissertations, Fall 2023 to Present

A significant number of children and youth are currently experiencing poor mental health. School counselors work with all students and are in a position to provide support to students experiencing mental health challenges. School counselors can also identify what may hinder children and youth from accessing mental health resources in their communities. This study explores how many school counselors engage in mental health counseling, how school counselors view their roles in addressing student mental health, and what barriers they perceive as keeping children and youth from accessing mental health and behavior services.

"In Any Other Circumstance I Am Not In Work Mode. I Am Clocked Out": Chappell Roan And The Objectified Persona, Aubry Louise

All Graduate Theses and Dissertations, Fall 2023 to Present

It is known that celebrities have influence on their audience’s attitudes and behaviors. Within the last few decades, multiple celebrities have created distinctions between their public/stage self and their private self, however, less is known about the ways that they differentiate between the two. This paper looks at celebrity public persona’s and how these persona’s influence their audience. I use Kayleigh Amstutz, otherwise known as Chappell Roan, as my case study. This thesis offers an analysis of how Amstutz talks about Kayleigh differently than Chappell within social media posts, interviews, and commentary from media outlets. I use the concepts of …

Pesticide Dissipation In Agroecosystems – Exploring Pesticide Fate And Transport Mechanisms To Protect Alternative Pollinators, Calvin Luu

All Graduate Theses and Dissertations, Fall 2023 to Present

Honey bees are the most well-known pollinators, but there exists thousands of other bee species that contribute to pollination; one such group of bees are the solitary bees. True to their namesake, solitary bees do not live in hives like honey bees. Some solitary bees, like alfalfa leafcutting bees (ALCB) and blue orchard bees, can pollinate crops more efficiently than honey bees. However, since they live solitary lives, pesticide exposure is much more harmful to their overall population. If one honey bee dies from pesticide exposure, the hive can still survive, and the queen bee will continue producing offspring. If …

Modeling Power Distribution Architectures And Maintaining Constant Power With Misalignment In Dynamic Wireless Charging Systems For Electric Vehicles, Mayank Chawla

All Graduate Theses and Dissertations, Fall 2023 to Present

With increasing demand for wireless power transfer systems from phone charging and medical devices, in-motion wireless charging of electric vehicles offers a unique advantage of charging the vehicle while in motion on an electrified roadway. Compared to the stationary or wired charging, electric vehicle users can significantly save time and cost with a reduction in the battery size. However, with large-scale infrastructure required for a wireless charging roadway and the driver’s ability to align with the electrified roadway, come significant challenges for the practical implementation of in-motion wireless charging systems.This dissertation aims to solve some of the problems associated with …