Digital Commons Network^™

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 …

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 …

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 …

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 …

Agronomic And Economic Evaluation Of Alternative Forage Crops Under Irrigation Technologies And Deficit Irrigation, Shikha Sharma

All Graduate Theses and Dissertations, Fall 2023 to Present

Water is becoming more limited in the western United States, including Utah, so farmers need forage crops that can produce well while using less irrigation water. This study examined how different forage crops respond to reduced irrigation and different irrigation application methods, and whether some crops can provide better economic returns under limited water conditions.

Field studies were conducted at three Utah locations, Cedar City, Logan, and Vernal, from 2020 to 2024. The alternative forage crops included teff, sorghum-sudangrass (sudex), and forage rye. For economic comparison, conventional forage crops included alfalfa, corn, and three-way small grains. Four to five irrigation …

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 …

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 …

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 …

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 …

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, …

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 …

Investigating Factors That Affect Students' Help-Seeking Strategies In A University-Level Foundational Mathematics Course, Randall I. Haws

All Graduate Theses and Dissertations, Fall 2023 to Present

Quantitative literacy, or the ability to understand and use mathematical information, is an important skill developed in college. However, required math courses can be a major obstacle for many students, and those who struggle to complete them are more likely to leave school without earning a degree. Understanding why some students seek help while others do not is key to improving student success.

This study explores how students in a university-level foundational mathematics course (college algebra) seek help and what factors influence their use of available support services. A total of 118 students completed a survey about their help-seeking behaviors, …

Comparing Error Correction Strategies In Discrete Trial Training For Children With Autism, Rachael Litchford

All Graduate Theses and Dissertations, Fall 2023 to Present

Children diagnosed with Autism Spectrum Disorder (ASD) often require structured, evidence-based teaching methods to promote skill acquisition. Discrete Trial Training (DTT) is one such approach widely used in Applied Behavior Analysis (ABA) to teach skills through repeated learning opportunities. However, limited research has compared the efficiency of specific error correction procedures within DTT. This study examined the comparative effectiveness of two error correction strategies, Active Student Response (ASR) and Model-Only, when acquiring tacting skills for children ages 2-10 with ASD. An alternating treatments design (ATD) was used to evaluate each strategy’s impact on skill acquisition, as measured by the percentage …

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 …

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 …

Understanding The Impact Of Environmental Change On Shorebird Abundance And Distribution Across The Intermountain West Over The Past 30 Years, Sharon Montecino

All Graduate Theses and Dissertations, Fall 2023 to Present

Shorebirds have declined worldwide over the past century, mainly due to wetland loss and degradation. Wetlands are sites that are temporarily or permanently flooded and provide critical habitat for shorebirds, especially in arid and semi-arid regions such as the Intermountain West. However, climate change and human water use threaten these wetlands, and how these threats may affect shorebirds in this region remains poorly understood. In the early 1990s, shorebird counts at over 160 wetlands across the Intermountain West provided a broad assessment of shorebird populations in the region. These counts remained the only large-scale surveys until 2022, when the Intermountain …

Integrating Space Use And Demography To Support Management Of An Endangered Alpine Ungulate, Danielle J. Berger

All Graduate Theses and Dissertations, Fall 2023 to Present

The places animals choose to live affect the food they find, the dangers they face, and the weather conditions they experience. These experiences influence whether individual animals survive and reproduce, which in turn affects the size and health of animal populations. Although scientists have long believed that animal movements play an important role in population trends, there has been limited real-world evidence showing this connection. Advances in GPS tracking technology now allow researchers to follow animals over long periods and better understand how movement influences survival. Using 20 years of GPS tracking data from the endangered Sierra Nevada bighorn sheep …

Incorporation Of Dairy Ingredients Into Chocolate And Caramel: Impact On Product Quality, Shelf Life, And Consumer Acceptance, Taelie Kennedy

All Graduate Theses and Dissertations, Fall 2023 to Present

Incorporating next-generation milk powders like milk protein isolate (MPI) and milk protein concentrate (MPC) into confections can increase protein content. Milk permeate powders (MPP) are byproducts of the production of high-protein dairy ingredients (MPC and MPI). Typically considered waste streams, growing awareness of sustainability has increased interest in the use of MPP in food. There is minimal research on the use of these ingredients in confections. 

This study evaluated the effects of incorporating milk protein powders and MPP into chocolate and the effects of replacing granulated sugar with MPP in caramel on product quality and consumer acceptance. 

Chocolate batches were …

Resilience, Hope, And Posttraumatic Growth Among Yazidi Refugees, Erin Elizabeth Larson

All Graduate Theses and Dissertations, Fall 2023 to Present

Although it has been more than a decade since the Islamic State of Iraq and Syria (ISIS) imposed genocide upon the Yazidi people, an ethnic minority indigenous to Kurdistan, research on the psychological health of this community is lacking. While traumatic experiences and the accumulation of stressors can overwhelm one’s capacity for resilience, making it especially difficult for refugees to adapt and recover from their experiences. Posttraumatic Growth Theory posits that individuals may overcome such challenges and even undergo positive life transformations. Data were collected from Yazidi young adults using an online survey and examined the associations between resilience, hope, …

The Impact Of Ai On The Landscape Design Process, Jacob Owen Huff

All Graduate Theses and Dissertations, Fall 2023 to Present

Artificial intelligence (AI) is becoming more common in design fields, including landscape architecture. For example, AI has been used to visually analyze park aesthetics and generate landscape design concepts (Jahani et al., 2022; Senem et al., 2023; Ploennigs & Berger, 2023). This study explores how AI, specifically an image-generation tool called Midjourney, affects the design process for landscape architecture students.

Students completed two design projects—one using AI-generated images and one using traditional, non-AI precedent images. Their final designs were evaluated by professional landscape architects who did not know which designs had been influenced by AI. Students also completed surveys about …

"Building Something Great!": Fifth-Grade Teachers Nurturing Hope Through Professional Learning Communities – A Telling Case, Matthew H. Huffaker

All Graduate Theses and Dissertations, Fall 2023 to Present

Teachers and educational leaders face numerous obstacles that can seem insurmountable but overcome through collaboration. “High-hope thinking provides a special advantage when we face obstacles in our goal attainment” (Snyder, 1994). Effective PLCs provide the fertile ground for teacher collaboration, influencing schoolwide communities and student learning (DuFour et al., 2016; Hord, 2004; van Es, 2012). Collaboratively identifying challenges and coming up with solutions with the support of others (what effective PLCs do) is an ideal setting for observing hope.

This study explored how hope is fostered among teachers during their weekly professional learning community meetings. Further, this study examined how …

Using A Prerequisite Skills Assessment To Identify Effective Communication Modalities For Mand Training, Christine White

All Graduate Theses and Dissertations, Fall 2023 to Present

Many children with Autism Spectrum Disorder (ASD) need support to learn how to communicate their wants and needs. This study examined three different ways to teach children to request preferred items or activities: using sign language, exchanging pictures, and speaking. We compared how three children learned each communication method to determine whether their existing skills influenced which method was most effective. No clear relationship was found between children's existing abilities and how well they learned each communication method. These findings suggest that selecting the most effective communication approach may require considering each child's individual strengths and learning history rather than …

Method Validation Of The Cdc Bottle Bioassay And A Historical Record Of Polycyclic Aromatic Hydrocarbons In Glacier National Park, Evah F. Peard

All Graduate Theses and Dissertations, Fall 2023 to Present

Certain contaminants can persist in the environment for long periods of time, build up within living tissues, travel far from their origin, and harm both ecosystems and organisms. This thesis focuses on two types of contaminants: insecticides and polycyclic aromatic hydrocarbons (PAHs). Insecticides are manufactured to control pests while PAHs are found in oil and gas products and can be produced by industry, vehicle engines, and wildfires. Understanding how harmful these contaminants are and where they end up in the environment is critical for protecting environmental health.

First, I evaluated a widely used test developed by the Centers for Disease …

From Evidence To Impact: Supporting Sensemaking And Instructional Revision In Stem Classrooms, Bonni Jones

All Graduate Theses and Dissertations, Fall 2023 to Present

Science and math literacy is crucial for informed citizenship and economic competitiveness, yet many students leave school without developing the critical thinking skills needed to understand and solve complex issues or pursue STEM careers. This disconnect often stems from traditional teaching methods that emphasize memorization and following steps over authentic reasoning and problem solving. This dissertation addresses this challenge by identifying how teachers in research studies have taught STEM in ways that develop students' ability to think, reason, and problem-solve like real scientists.

By analyzing research on instruction that incorporates modeling, inquiry, and sensemaking, and working directly with teachers, this …

Social Support As A Resource In Emerging Adulthood: Examining Siblings' Unique Potential, Leslie A. Page

All Graduate Theses and Dissertations, Fall 2023 to Present

This dissertation consists of three studies that examined the influence of multiple relational processes and partners across adolescence and emerging adulthood. Drawing on family systems (Bowen, 1978; Cox & Paley, 1997) and social convoy (Antonucci et al., 2013) theories, social support was conceptualized as a relational dimension that shapes how close others function as resources during key developmental transitions. With this perspective, siblings were included as important, but relatively understudied, members of the social convoy who may provide enduring and flexible support that is extremely relevant for this population. In Study 1, support was treated as an outcome of longitudinal …

The Effects Of Psychological Stress On Gut Health In Mice Fed Either A Healthy Diet Or The Total Western Diet, David Keenan Thomas Prescott

All Graduate Theses and Dissertations, Fall 2023 to Present

The Total Western Diet (TWD), a rodent diet designed to model the typical American dietary pattern, has been shown to worsen inflammation and colitis severity in mice. Psychological stress has also been associated with increased intestinal inflammation, barrier dysfunction, and alterations to the gut microbiome. The goal of this study was to determine whether combining the TWD with psychological stress would further worsen colitis severity and alter the gut microbiome. To investigate this, mice were fed either a healthy control diet or the TWD and exposed to psychological stress using a social disruption stress model. Colitis was induced using established …

Impact Of Chronic Stress And Nutrition On Functional Connectivity And Neural Networks In Young Kichwa Children From The Ecuadorian Amazon Rainforest, Matthew L. Cook

All Graduate Theses and Dissertations, Fall 2023 to Present

Early childhood is a critical period for brain development. Positive and negative experiences during this time can have lasting effects on learning, health, and well-being. However, most research on children’s brain development has been conducted in wealthy, industrialized nations, leaving important gaps in our understanding of how children develop in other cultural and environmental contexts.

This study examined brain development in Indigenous Kichwa children living in two rural communities in the Ecuadorian Amazon Rainforest. The goal was to better understand how chronic stress and nutrition may influence a child’s developing brain during early childhood. Children participated in noninvasive brain assessments …

Effects Of Single-Session Interventions On Youth Internalizing Problems, Thomas K. Franzmann

All Graduate Theses and Dissertations, Fall 2023 to Present

Anxiety and depression are among the most common mental health concerns young people face, and they often interfere with school, friendships, family life, and long-term well-being. Even though effective therapies exist, only about half of youth who need care ever receive it, and among those who do start treatment, the most common total number of sessions a young person attends is one. This gap between what young people need and what they actually receive raises a practical question for the field: can a single, well-designed meeting with a provider produce meaningful change for some youth and families, and what should …

Carbon Cycling, Salinization, And Long-Term Water Quality Trends In Rocky Mountain Streams, Allyson J. Marrs

All Graduate Theses and Dissertations, Fall 2023 to Present

Humans have greatly affected streams and rivers worldwide through urbanization, agriculture, and water use. The purpose of my dissertation is to increase our understanding of various human impacts on rivers. In chapter two, I aim to determine whether there are differences in greenhouse gas (GHG) emissions between a natural river and manmade canals. I did this by measuring the emissions and dissolved concentrations of three of the most prevalent GHGs, carbon dioxide (CO₂), methane (CH₄), and nitrous oxide (N₂O). I found that most of the sites I studied were emitting CO₂ and CH …