Digital Commons Network^™

Reconfigurable Antennas Using Varactors On A Planar Parasitic Layer And Pin Diodes On A Dome Parasitic Layer, Andrew J. Hendricks

All Graduate Theses and Dissertations, Fall 2023 to Present

This research explores two types of reconfigurable, steerable antennas. These antennas change their beam direction based on electric input signals. The antennas have a layer that overlays the main antenna circuit board. The layer has small copper rectangles (pixels) that may be connected using either varactor diodes (which behave as voltage-controlled capacitors) or PIN diodes (electronic switches). The first antenna can steer in the xz-plane in any direction within about 23° from boresight (straight up from the antenna) and in the yz-plane to about 29° from boresight. The antenna uses varactor diodes on a planar layer. The second …

An Autohistoria-Teoría Of A Pasifika Neptantlera, Belinda 'Ofakihevahanoa Fotu

All Graduate Theses and Dissertations, Fall 2023 to Present

This study was an autohistoria-teoría, a type of autoethnography, where I focused on my writing process as a Pasifika researcher creating a middle- grade fiction. As the researcher, my questions delved into how I engage in writing for a majority-culture dominated publication house in a Western-world writing genre while maintaining the cultural significance of the ancient Pasifika mythologies I reproduced and recontextualized in the novel. The research site was my writing process, and the data gathered came from the variety of ways I navigated cultural stimuli specific to writing the novel. The outcome engaged with the specific way Pasifika (and …

Effects Of Training And Self-Monitoring On Paraeducators' Use Of Behavior Specific Praise, Camille J. Lopez

All Graduate Theses and Dissertations, Fall 2023 to Present

Paraeducators support students with disabilities in special education classrooms but often receive limited training in effective behavior support strategies. This study examined whether training combined with self-monitoring increased paraeducators’ use of positive, specific praise and reduced the use of reprimands during instruction. Paraeducators were trained to use and track their own praise while working with students. Results showed increased use of positive praise and decreased reprimands following the intervention. These findings suggest that brief, low-cost training and self-monitoring can improve paraeducator instructional practices and support positive classroom environments for students with disabilities.

Assessing Young Children's Computational Thinking: Validation Of Items And Item Design Features, And Diagnostic Approaches, Chungsoo Na

All Graduate Theses and Dissertations, Fall 2023 to Present

The goals of this multiple-paper dissertation are to evaluate the psychometric evidence of the Computational and Spatial Thinking Assessment (CaST), designed and developed by the Coding in Kindergarten (CiK) research team (supported by NSF #1842116). In Chapter 2 (Paper 1), I evaluate the psychometric quality of the CaST assessment at the item level. The CaST has moderate item difficulty and high item discrimination, on average, with high reliability and no gender- or age-related item bias. In Chapter 3 (Paper 2), I identify seven item design features from the CaST assessment and examine their impact on item difficulty. All item design …

A Mixed-Methods Investigation Of Physician Compassion In Consultations For Chronic Primary Pain, Sarah Daehler

All Graduate Theses and Dissertations, Fall 2023 to Present

Chronic primary pain refers to physical pain that has no apparent organic cause, cannot be explained by another condition, and has associated psychological distress or functional impairment. Chronic primary pain is common and can significantly interfere with functioning, including occupational or social functioning. Research has shown that physicians struggle to treat this population, with many physicians reporting feeling unequipped and many patients feeling that their physicians are unhelpful and dismissive. Compassion may play a key role in improving these difficult interactions. The present study analyzed a sample of 99 participants with chronic pain and 100 healthy controls to learn more …

Freshwater Mussel Reintroduction And Recolonization Habitat Modeling Using Hydraulic, Sediment And Geomorphic Parameters, Megan Elizabeth Dinicola

All Graduate Theses and Dissertations, Fall 2023 to Present

Freshwater mussels are an important group of aquatic animals that live within the riverbed, but their populations have been drastically reduced by habitat alteration and other anthropogenic activities. In an effort to bolster populations, river managers and biologists are using mussel reintroductions as part of their restoration efforts but there are gaps in our understanding of where to reintroduce mussels within a river to see them create self-sustaining populations. This research helps shrink this gap by better understanding the physical habitat needs and population expansion potential of subadult freshwater mussels, or the size of mussel that hatcheries grow for reintroduction, …

Effects Of Subsurface-Drip-Irrigation On Alfalfa Evapotranspiration In The Intermountain West, Namuna Dhakal

All Graduate Theses and Dissertations, Fall 2023 to Present

Alfalfa is one of Utah’s most important crops, but it is also the largest agricultural consumer of water. Because the state faces frequent droughts and growing pressure on limited water supplies, farmers and water managers are increasingly interested in irrigation systems that could reduce water use. Subsurface drip irrigation (SDI), which delivers water directly to plant roots through buried drip lines, has shown promising results in other regions, where it often reduces water consumption and increases yield. However, little research has evaluated SDI under Utah’s unique climate, soils, and high-elevation valleys.

This study compared an SDI system with a traditional …

Evaluating The Feasibility, Acceptability, And Preliminary Efficacy Of An Online Acceptance And Commitment Therapy Program To Improve Dietary Quality In Highly Stressed Adults, Francesca M. Knudsen

All Graduate Theses and Dissertations, Fall 2023 to Present

Stress can negatively affect both mental and physical health, which can increase the risk for chronic illness. When people feel stressed, they may also find it harder to make healthy food choices, which can further impact their health. Despite this, there are limited treatments designed to help people improve their dietary quality while managing stress. Acceptance and commitment therapy (ACT) is an evidence-based psychological approach that helps people respond more effectively to difficult thoughts and emotions while behaving in ways that are aligned with their personal values. This study tested whether a brief, online ACT-based program, combined with coaching phone …

Unpacking Science Achievement: Institutional Alignment And Mediating Conditions In A High-Performing Charter School, Brenda L. Bennett

All Graduate Theses and Dissertations, Fall 2023 to Present

This study examined how science instruction was sustained over time within a high-performing public elementary charter school. Rather than focusing on individual programs or teaching strategies, the research explored how schoolwide systems, relationships, and supports worked together to shape classroom practice.

The study focused on one public K–6 charter school in a western state with consistently strong science performance on state-reported measures and examined how institutional, organizational, and classroom conditions mediated the relationship between science instruction expectations articulated in state and charter policy and teachers’ enacted practice.

Results suggested that strong science instruction was not produced through strict mandates or …

Cultural Adaptation Of A Single Session Acceptance And Commitment Therapy Guide For College Students In Uganda, Miriam Mukasa Kasozi

All Graduate Theses and Dissertations, Fall 2023 to Present

Mental health problems such as depression, anxiety, and stress are common among Ugandan university students and can make it difficult for them to succeed in school or maintain well-being. However, many students do not have access to professional mental health care. Digital self-help programs can make support more available, especially when they are designed to fit the local culture and context. This project examined how an online program called ACT Guide Lite, which teaches skills from Acceptance and Commitment Therapy (ACT), could be adapted for use with Ugandan college students. Students and other university community members first completed the program …

Investigating Utah's Watershed Restoration Initiative: A Qualitative Case Study Of A State-Managed Collaborative Platform, Casey Trout

All Graduate Theses and Dissertations, Fall 2023 to Present

Collaboration is necessary to address complex, cross-jurisdictional natural resource problems. To better understand the benefits and drawbacks of innovative collaborative structures, this research examined the Utah Watershed Restoration Initiative (WRI). WRI is a state-managed program in Utah that implements cross-boundary habitat restoration projects. Local, state, and federal government agencies as well as non-profit organizations convene on five regional teams to design and evaluate projects. Project partners are engaged at a local level while most program administration occurs at the state level. A case study of WRI was conducted, making use of interviews with 33 participants, document review, and field observations. …

Two Applications Of Lifting-Line Theory For The Design Of Efficient Aircraft, Amanda K. Olsen

All Graduate Theses and Dissertations, Fall 2023 to Present

Numerical lifting-line is a tool that can be used to evaluate the forces and moments of an aircraft wing. This method has limitations but it is beneficial in obtaining a large set of results with relatively little computational power. This research seeks to analyze two different flight scenarios through the use of two numerical lifting-line tools developed at the Utah State University AeroLab. The first scenario involves an aircraft in ground effect flight. When an aircraft flies close to the ground, a phenomenon called ground effect occurs where the lift is increased and the induced drag is decreased. Therefore, flying …

Teaching In The Age Of Artificial Intelligence: A Hermeneutic Phenomenological Study Of Teachers' Lived Experiences, Nicholas Ricks Harris

All Graduate Theses and Dissertations, Fall 2023 to Present

Artificial intelligence (AI) is rapidly changing education, creating new opportunities for teaching and learning while also raising challenges for teachers. Although schools are encouraging the use of AI, little is known about how teachers experience this transition or how it affects their professional roles. This study explored teachers’ lived experiences as they begin working with AI, using a phenomenological research approach to understand both what they encounter and how they make sense of those experiences. Through interviews with teachers who have recently engaged with AI in their practice, the research identifies themes that reveal opportunities, challenges, and shifts in professional …

Characterizing Metabolic Flux Of Plant Secondary Metabolites From Diverse Animal-Source Foods To Humans, Muhammad Ahsin

All Graduate Theses and Dissertations, Fall 2023 to Present

There is a popular saying: “You are what you eat.” But does this also mean, “You are what your food eats”? This dissertation explores that question by examining how farming practices shape the nutritional quality of meat—and what, if anything, those differences mean for the people who consume it. While modern livestock production and nutrition research often emphasize protein and fat, this work tests the idea that animals function as biological mediators, linking soil and plant conditions to human diets through the chemical composition of meat and milk. To evaluate this hypothesis, we tracked health-relevant plant compounds— phytonutrients—across the soil–plant–animal–human …

Drought-Tolerant Plants Of Great Salt Lake: Determining Dormancy Break, Germination, And Seeding Timing Requirements To Improve Restoration Under Hydrologically Extreme Conditions, Montana Horchler

All Graduate Theses and Dissertations, Fall 2023 to Present

Wetlands are declining worldwide, and those in arid regions are especially vulnerable to climate change, drought, water diversions, and other human pressures. As a result, land managers increasingly rely on active revegetation to re-establish native plant communities and their associated ecosystem functions. Restoration that utilizes seeds as the propagule source is often the most cost-effective way to revegetate large areas, but in highly variable environments such as exist at Great Salt Lake, Utah, drought and flooding regularly limit plant establishment. Restoration practitioners require science-informed strategies to reach their goal of establishing diverse native plant communities with high native species cover. …

The Dark Side Of Sport: Exploring Conceptualizations And Operationalizations Of Authority Figure-Athlete Abuse, Katherine Nicole Alexander

All Graduate Theses and Dissertations, Fall 2023 to Present

Although sport can be a fun and positive environment, it can also be a unique and common setting for athlete abuse. Coaches and other authority figures can serve in positive and negative caregiving roles, and many athletes report experiencing at least one form of abuse perpetrated by these important authorities during their sporting careers. We have less research on experiences of abuse in athletes from the United States. The current dissertation was designed to explore ways to more effectively and accurately define and measure athlete abuse perpetrated by authorities and coaches among adults in the United States. Given that there …

Continuous Symmetry Discovery And Enforcement Using Vector Fields With Application To Time Series And Image Data, Benjamin D. Shaw

All Graduate Theses and Dissertations, Fall 2023 to Present

Machine learning powers many technologies we use every day, from image classification in computer vision to analyzing time series data such as sensor readings or financial trends. One way to make these systems smarter and more reliable is by using symmetry, meaning patterns that remain unchanged under certain transformations, such as rotations for images or uniform changes in signal amplitude for time series. Discovering these patterns can improve understanding of data and help build models that perform well in new situations. 

Current methods for finding symmetry often rely on large neural networks and are limited to simple transformations like stretching …

Counterfactual Explanations For Time Series Through Local Pattern Mining And Generative Models, Omar Bahri

All Graduate Theses and Dissertations, Fall 2023 to Present

Machine learning systems increasingly make decisions that affect people’s lives, from medical diagnoses to loan approvals. When these systems analyze time series data—sequences of measurements collected over time, such as heart rhythms or sensor readings—users need to understand why a particular prediction was made. Counterfactual explanations address this need by answering “what-if” questions: what would need to change in the input for the system to make a different prediction? 

This dissertation develops methods for generating counterfactual explanations specifically designed for time series data. Time series often contain distinctive local patterns—short subsequences that distinguish one class from another. For example, a …

Evaluation Of Fertilizer Recommendation And Soil Amendment Impacts On Crop Production In The Intermountain West, Megan Baker

All Graduate Theses and Dissertations, Fall 2023 to Present

Fertilizers improve crop yield and quality by supplying crops with essential nutrients, but can also be a significant input cost. Determining what nutrients and rates to apply for optimal crop growth can be difficult, leading many growers to use external sources for these decisions. Land-grant universities are a common source for fertilizer recommendations, but often based on decades-old research and should be evaluated periodically to verify effectiveness and calibrated to current soil analysis methods. Current Utah State University (USU) guidelines for sulfur (S) and zinc (Zn) were tested across Utah in on-farm trials in 2021-2025. Zinc applications of 5 or …

Social And Institutional Factors Influencing Restoration Decisions In Sagebrush Plant Communities In The Great Basin, Carmen Calzado-Martínez

All Graduate Theses and Dissertations, Fall 2023 to Present

Sagebrush landscapes of the Great Basin in the western United States have changed dramatically over the past century. Invasive grasses, repeated wildfires, and past land-use practices have made it increasingly difficult for native plant communities to recover once they are damaged. Most restoration efforts occur after disturbances such as wildfire, when ecosystems may already be severely degraded. An alternative approach is proactive restoration, which aims to strengthen ecosystems before major damage occurs. 

This dissertation examines whether proactive restoration strategies could realistically be used in sagebrush rangelands and what factors influence their adoption. The research combines three complementary approaches. First, interviews …

Comparing Strategies For Wetland Revegetation In An Uncertain Water Future, Hailey M. Machnikowski

All Graduate Theses and Dissertations, Fall 2023 to Present

Wetlands worldwide are expected to experience more frequent and intense droughts and floods due to climate change. These shifting water conditions introduce challenges to restoring wetland plants, especially using direct seeding. Seeding is cost and labor-efficient compared to planting, but seeds and seedlings are highly vulnerable to water stress, so restoration efforts often fail when conditions are too wet or dry. Understanding how to improve seed-based revegetation under these conditions is increasingly important. Therefore, we sought to understand the response, measured by percent canopy cover or dry biomass weights, of native plants to different durations of drought in greenhouse experiments, …

An Analysis Of The War On Terror In Textbooks, Kason Kendall

All Graduate Theses and Dissertations, Fall 2023 to Present

This study analyzes how the War on Terror is presented in history textbooks used in the United States and Brazil. Textbooks play an important role in shaping how students understand major global events, including wars, national security, and international relations. However, these materials do not simply present facts, they also reflect specific perspectives and priorities.

The purpose of this study is to analyze how key topics related to the War on Terror, such as the justification for the Iraq War, domestic security policies, treatment of prisoners, and public dissent are portrayed in textbooks from other countries. By comparing these narratives, …

Forage Responses To Biological Inoculant And Seed Rates In The Intermountain West, Roy Reid

All Graduate Theses and Dissertations, Fall 2023 to Present

Improving the efficiency of fertilizer and seed use is increasingly important for forage producers in the Intermountain West, where alfalfa and silage corn form the foundation of dairy and livestock feed. This thesis evaluates two strategies designed to boost crop productivity: microbial fertilizer coatings and variable-rate seeding.

The first study examined whether Powercoat®, a fertilizer-applied microbial inoculant, could enhance yield, forage quality, or soil phosphorus availability in alfalfa grown on four commercial fields in northern Utah. Across all locations, fertilizer increased yield at only two sites, and Powercoat did not provide additional improvements in yield, forage quality, or soil nutrient …

Equity, Diversity, And Inclusion Infrastructures And Faculty Composition: Associations With Undergraduate Student Outcomes At R1 Universities 2011-2021, Niyonta Nahia Chowdhury

All Graduate Theses and Dissertations, Fall 2023 to Present

This study explores how the structure and composition of research universities relate to student outcomes. Specifically, it asks whether having visible Equity, Diversity, and Inclusion (EDI) infrastructures and diverse faculty representation is associated with who enrolls, who graduates, and how graduation rates differ within racial groups at R1 universities in the United States. Using national data from 2011 to 2021, the project analyzes enrollment and graduation patterns across institutions while accounting for differences in geography, governance, and state political context.

Rather than focusing on individual students, the study looks at institutional patterns. It examines how the racial and gender makeup …

Does Psychosocial Stress Moderate The Association Between Indicators Of Vascular Health And Cognitive Performance: An Examination In Native Hawaiian - Pacific Islander And Non-Nhpi Older Adults, Maddy Mills

All Graduate Theses and Dissertations, Fall 2023 to Present

Late-life cognitive decline and dementia that are unrelated to normal aging are a source of major global health concerns. Vascular risk factors, including high blood pressure, high cholesterol, and diabetes, along with psychosocial stress, are well-established risk factors for cognitive decline. However, no research has explored how these variables interact to influence cognitive performance in older adults. Native Hawaiian-Pacific Islanders (NHPI) face disproportionate rates of vascular risk factors linked to cognitive decline, yet this population has been historically underrepresented in health research. As a result, limited evidence exists regarding how these factors collectively impact cognitive performance in this population. This …

The Role Of Response Time In Math Anxiety, Christine K. Hartmann

All Graduate Theses and Dissertations, Fall 2023 to Present

Math anxiety is characterized by feelings of discomfort or distress that are triggered when an individual is tasked with using numbers. Math anxiety impacts people at all ages, from early elementary school into adulthood (for review see Ramirez et al., 2018). In these studies, we investigated the cognitive impact that math anxiety has on both children and adults by measuring their math anxiety and reaction time on two tasks. The first task was the arithmetic affective priming task (AAPT), which purportedly shows that those with math anxiety tend to complete math tasks more efficiently (faster) when they are primed to …

Advancing Context-Aware Detection Of Socially Harmful Discourse Using Transformer-Based Models, Santosh Chapagain

All Graduate Theses and Dissertations, Fall 2023 to Present

Social media platforms are a central part of modern communication, shaping how people share ideas, build communities, and discuss social issues. While these spaces can support connection and self expression, they also enable the spread of harmful language such as hate speech. At the same time, social media is an important place where members of marginalized communities, including sexual and gender minorities, express stress, discrimination, and emotional challenges in ways that are often indirect and context dependent.

This research examines whether modern artificial intelligence systems can better identify harmful language and expressions of minority stress in online posts. The study …

Analyzing The Influence Of Stem Project-Based Learning On Students' Perceptions And Career Interest In Stem, Melissa S. Barker

All Graduate Theses and Dissertations, Fall 2023 to Present

Although science, technology, engineering, and mathematics (STEM) enrichment programs aim to increase participation in STEM, the design features that meaningfully influence adolescents’ task values and career-related beliefs remain insufficiently specified. The purpose of this study was to investigate whether STEM PBL activities designed with an interest-focused theoretical lens of Subjective Task Value (STV) and Social Cognitive Career Theory (SCCT) influence students’ perceptions of STEM courses, majors, and careers. Additionally, I sought to understand what elements of the STEM PBL experience were most impactful. I designed and taught STEM PBL activities for students from the Native American lands in southeastern Utah …

Post-Wildfire Erosion And Biogeochemistry: Integrating Aerial Imagery And Soil Testing To Assess Landscape Recovery, Justin A. Allred

All Graduate Theses and Dissertations, Fall 2023 to Present

After a wildfire, land managers are required to monitor large tracts of land with limited time and budgets. Traditionally, tracking landscape recovery is a time intensive process. This research explored the effectiveness of using drones (UAVs), strategic soil sampling, and computer modeling as additional tools for land managers in order to monitor the recovery more efficiently.

By using drones to collect aerial imagery and using machine learning, plant regrowth was monitored in back-to-back years. The machine learning model performed well at telling broad groups apart (trees vs grass) but it struggled to identify differences between plant species. Because many plants …

Factors Affecting Mathematics Teachers’ Instructional Decision-Making: An Ecological Systems Theory Multiple-Case Study, Camille M. Lund

All Graduate Theses and Dissertations, Fall 2023 to Present

Though research on effective mathematics instructional strategies is robust, there remains a gap between research and the instruction that takes place in mathematics classrooms. One such effective instructional practice—mathematical student discourse (MSD)—has been extensively researched, but little research has looked holistically at the ecological factors that interact to influence teacher decision-making for this practice. In this qualitative multiple-case dissertation study using Urie Bronfenbrenner’s ecological systems theory as a theoretical lens, I conducted semi-structured interviews with three elementary teachers who teach mathematics in districts across northern Utah. These interviews utilized the researcher-created Ecological Factors Map to explore how teachers described the …