Digital Commons Network^™

Physics-Informed Neural Network For Maximum Detectable Distance Estimation In Mobile Gamma Spectrometry, Nancy A. Ibrahim

Theses and Dissertations

Accurate estimation of the Maximum Detectable Distance (MDD) is critical for environmental remediation, nuclear incident response, and public safety. Conventional approaches assume stationary detectors and rely on computationally intensive simulations, limiting their applicability for mobile, real-time surveys. Mobile gamma spectrometry introduces additional complexities due to detector motion, variable acquisition times, and heterogeneous backgrounds. This study addresses the central question of how effectively a Physics-Informed Neural Network (PINN) can estimate MDD for mobile gamma spectrometry, while maintaining both accuracy and computational efficiency under dynamically changing environmental conditions. A multi-phase approach was employed, combining field data collection, computational modeling, and operational tool …

Evaluating The Effects Of Biostimulants On Apple Coloration, Patrick G. Owens

Theses and Dissertations

Apple peel color is one determining factor of apple quality and is a highly sought after trait by both growers and consumers. Historically plant growth regulators (PGRs) such as daminozide and auxins have been used to induce a greater amount of red color in the peel, but these products typically have negative production impacts and raise environmental concerns. One new area of interest is in called biostimulants. This study investigated the effects of two experimental biostimulants (MCEN1 and MCEN2) applied at varying rates and timings, as well as a commercially available plant growth regulator (Blush® 2X), on ‘Honeycrisp’ apple color …

Small Area Estimation Methods For County-Level Forest Biomass Estimation, Pratyush Dhungana

Theses and Dissertations

We evaluated small area estimation (SAE) methods for county-level forest biomass across four Forest Inventory and Analysis (FIA) regions in the contiguous United States using the coefficient of variation and relative root mean squared error. The Standard Fay–Herriot (FH) model was compared with multivariate, spatial, and measurement-error extensions, while the unit-level Battese–Harter–Fuller (BHF) model was compared with mixed-effects random forests (MERF) with auxiliary data from remote sensing. Spatial FH improved precision when spatial dependence was strong; otherwise, Standard FH was more reliable. All FH models were effective with fewer than 100 plots. Measurement-Error FH produced more accurate estimates than FIA …

Leveraging Google Earth Engine For Computationally Efficient Pixel-Level Analysis And Vector Delineation From Satellite Data., Rishita Garg

Theses and Dissertations

Analyzing large-scale, high-resolution satellite imagery is a computationally intensive task requiring time and computing resources. This can be accelerated using cloud computing platforms such as Google Earth Engine (GEE) where computational and storage requirements can be scaled based on demand. However, cloud-based platforms for processing high-resolution imagery remain underutilized in environmental applications such as agriculture, and forest health. This thesis explored the application of GEE to two geospatial problems in agricultural conservation and disease mapping in forestry: 1) Extraction of agricultural field boundaries from Sentinel-2 satellite imagery, for use in conservation, precision agriculture, land management, and organization, etc., and 2) …

Study On Vehicle-Pedestrian Interaction Autonomy By Risk Potential Theory, Riku Kikuta

Theses and Dissertations

Vehicle–pedestrian interaction is a critical aspect of autonomous vehicle (AV) development, as socially acceptable AVs must account for pedestrian intention and behavior. Risk Potential (RP) theory provides a framework to build human-like AVs by modeling expert driver risk perception, but conventional RP models treat pedestrians as static obstacles and neglect their dynamics. This dissertation extends RP theory by incorporating pedestrian velocity and orientation into three new models: the RP velocity model, the RP related-velocity model, and the RP Pedestrian Potential Position (PPP) model. These models were implemented in the Navigating All Terrains Using Robotic Exploration (NATURE) autonomy stack and tested …

Validation And Efficacy Of A Novel External Ankle Support Device For The Prevention Of Lateral Ankle Sprains, Sally Kennon Barfield

Theses and Dissertations

Ankle sprains are a common injury in sports and in life and can lead to debilitating consequences if not managed properly. Current prevention methods are limited to bracing or taping of the ankle. While these methods have been shown to help in mitigation of ankle sprains, associated issues such as performance decrements and discomfort have been noted in the currently available literature. The BetterGuards is a novel external ankle support that has been touted as the key to the issues presented by more traditional prevention methods. The purpose of this study was to determine both the effectiveness of the BetterGuards …

Improvement Of Spot Spraying Treatments Using Precision Application Technologies, Steffen Telgmann

Theses and Dissertations

Chemical plant protection is widely adopted in agriculture and plays a crucial role in maximizing plant production. Several developments for site-specific applications have been implemented in chemical plant protection, driven by economic, social, and environmental considerations. Spot spraying technology, which utilizes single nozzles or a limited number of nozzles to treat specific areas, is now available and gaining market penetration. However, its performance depends on carefully optimized application parameters to ensure consistent coverage and efficacy, thereby mitigating both under- and overdosing. To address concerns including reduced efficacy, resistance evolution, and environmental impacts, this work researches the effects of nozzle selection …

A Case Study On Redesigning Classroom Activities And Assessments For Generation Z Students, Sushma Shrinivasan

Theses and Dissertations

This dissertation investigates the dynamic interplay between pedagogical strategies, learner diversity, and emerging educational technologies through three interconnected studies. Study 1 compares Traditional instruction, Problem-Based Learning (PBL), and Simulation-Based Learning (SBL), revealing that while PBL and SBL enhance student performance—particularly PBL—their impact on perceived learning varies. Notably, SBL reduced perceived learning despite strong outcomes, underscoring the affective and metacognitive complexities of active learning. Study 2 examines the role of demographic factors such as gender, ethnicity, employment, and first-generation status, finding no significant main effects but identifying a key two-way and three-way interactions, suggesting that instructional effectiveness is influenced by the …

Integrated Experimental, Numerical, And Machine-Learning Framework For The Analysis Of Spray Dynamics In Diesel And Gasoline Direct-Injection (Gdi) Engines, Yassine El Marnissi

Theses and Dissertations

The regulation of diesel and gasoline direct injection (GDI) during cold starts has become subject to stricter numerical limits by both the Environmental Protection Agency (EPA) in the US and the European Commission (EC). For diesel engines, the EPA’s Clean Trucks Plan (Model Year 2027+) sets a certification NOₓ limit of 0.035 g/bhp-hr and an in-use fleet average limit of 0.050 g/bhp-hr, along with a PM limit of 0.005 g/bhp-hr, representing an 82.5% reduction in NOₓ compared to the former 0.2 g/bhp-hr standard. For gasoline engines, US standards regulate cold-start pollutants such as hydrocarbons (HC) ranging from 0.03 to 0.08 …

Multiple Baseline Single-Case Study: Narrative Resiliency Intervention For Couples With Adverse Childhood Experiences, Emma Elizabeth Allen

Theses and Dissertations

A multiple baseline single case study design was used to examine the effects of a narrative and resiliency-based intervention for couples with adverse childhood experiences (ACEs). Using piecewise multilevel modeling (MLM), the study evaluated changes in depressive symptoms, dyadic coping (DCI), and growth and empowerment measure (Emotional Empowerment Scale [EES-14] and 12 Scenarios [12S]) across waitlist and treatment phases. Five couples (10 individuals) participated in up to 17 waves, with staggered baseline and treatment lengths across dyads. Results indicated significant fixed effects of the 12S subscale for growth and empowerment during the treatment phase. There were no statistically significant fixed …

Power Resilience In Utah's Water Sector: A Survey Of Stakeholder Practices, Preferences And Potential, Tyler Christopher Peterson

Theses and Dissertations

Drinking water and wastewater services are vulnerable to disruptions because they rely heavily on the electric grid. As a result, power outages can lead to water outages, creating cascading failures that compromise sanitation, firefighting, healthcare, and daily routines. Although an important topic, there are little to no studies of water and wastewater power resilience at a geographic or state level. In this study we investigate the extent of existing backup power and renewable energy integration as well as the motivations and barriers around their power resilience. We collect our data through semi-structured interviews with staff at 19 urban and rural …

Climate-Driven Flood Risk Mapping And Adaptive Strategy Modelling For Coastal Tamil Nadu, Sakthi Kiran Dr Mr

Theses and Dissertations

Background: Tamil Nadu’s coastal corridor (Cuddalore–Sirkazhi; ~2,740 km²) experiences recurring floods driven by climate change, rapid urban expansion, and inadequate drainage across low-lying deltaic terrain. Existing flood assessments remain largely reactive and rely on static methods that fail to incorporate future climate projections, demographic growth, and evolving urban patterns.

Methods: This research develops a dynamic, climate-resilient flood risk framework integrating (i) long-term hydroclimatic trend analysis (1984–2023), (ii) satellite-based flood hazard mapping using multi-temporal Sentinel-1A and RISAT-1A SAR, (iii) CORDEX REMO2015 (RCP 4.5)–driven HEC-RAS 2D hydrodynamic modelling, (iv) machine-learning-based susceptibility modelling (RF, DT, SVM), and (v) scenario-based evaluation of structural mitigation …

The Impact Of Social Factors On Vagally Mediated Parasympathetic Activity, Andrew Scot Proctor

Theses and Dissertations

Loneliness and social disconnection are recognized risk factors for morbidity and mortality, yet the psychophysiological pathways remain contested. This dissertation examines how social factors relate to vagally mediated parasympathetic activity indexed by heart rate variability (HRV) and tests whether conversational interventions with a human or a large-language-model (LLM)-based companion can acutely reduce loneliness and enhance connection. Across two university sites (BYU, UCSD), N=297 participants (18-27 years) were randomized to (a) a reciprocal self-disclosure conversation with a trained human confederate, (b) a parallel, vocalized LLM chatbot conversation, or (c) a non-social, vocal reading control. Resting HRV (RMSSD, SDNN, HF-HRV) was recorded …

Experimental And Theoretical Characterization Of Molten Salt Thermal Conductivity, Jacob C. Numbers

Theses and Dissertations

Molten salts form an ideal heat transfer fluid for advanced energy generation systems, including molten salt reactors (MSR). Accurate characterization of molten salt thermal conductivity is needed to confidently predict transient thermal behavior and optimize salt properties. Measurements are hindered by salts' challenging material properties, which---in the case of the needle probe device---induced unaccounted physical changes that limited its accuracy and repeatability. Sparse thermal conductivity data in general is exacerbated by a limited fundamental understanding of molecular energy transfer in liquids. This work extends the experimental capacity for compositional studies using the needle probe and proposes a theoretical model for …

Exploring The Potential Of Artificial Intelligence To Improve The Journal Peer Review Process, Eliza Fanny Bondah

Theses and Dissertations

Academic publishing depends on the peer review process to guarantee quality, scholarly rigor, and credibility, but the traditional peer review system receives mounting criticism because of its inefficient operations, biased judgments, and irregular standards. This study explores how artificial intelligence (AI) can improve journal peer review systems to solve a variety of issues, including reducing reviewer exhaustion, minimizing bias, improving consistency, and accelerating the review process. Current literature shows AI as a promising yet controversial solution, which may provide structured feedback with improved consistency and efficiency. Our study examined 52 human reviews together with 26 AI-generated reviews from EdTechnica--An Open …

Bayesian Alignment Prior To Connectionist Temporal Classification Loss, Lawry Sorenson

Theses and Dissertations

We propose revisions of Connectionist Temporal Classification (CTC) loss and forced alignment to support longer input sequences. CTC loss is normally used for training in speech and handwriting recognition tasks when the labels are not fully aligned with the data, while forced alignment is a downstream task that finds the optimal path for segmentation purposes. The current implementations consider all possible alignments between the input and label, which grows exponentially with the size of the input. We show that in cases when silence is removed and speaking rate is consistent, the true alignment is a mostly straight line across time …

Exploring Adjunct Faculity Member Acceptance To Learning Management Systems When Transitioning To Online Course Instruction: A Traditional Case Study, Maryelizabeth Mcardle

Theses and Dissertations

In recent years, the typical college student wearing a university sweatshirt and holding a backpack has evolved to include a rising population of adult learners returning to college (Morris, 2020). According to the Educational Advisory Board, adult learners are defined as students aged 25 and older (Morris, 2020). Of the approximately 20 million students enrolled in a degree-earning program in 2019, nearly 6.5 million were adult learners (Morris, 2020). The purpose of this qualitative case study is to understand adjunct faculty members' experiences, which led to positive intentions to use and actual usage of the LMS when assigned to instruct …

Mitochondrial Insoluble Aggregates In Aging And Alzheimer’S Disease Models: Cross-Species Proteomic Integration, Identification Of Conserved Candidates, And Pharmacological Disruption Of Eef-2 Interactions, Sonu Pahal

Theses and Dissertations

Protein aggregation within mitochondria emerges early in both aging and Alzheimer’s disease (AD) and contributes to progressive loss of proteostasis. Insoluble mitochondrial aggregate fractions from Caenorhabditis elegans revealed extensive enrichment of metabolic and translational proteins that also appear in human Alzheimer hippocampal aggregates. Comparative analysis across age and genotype identified a conserved subset of aggregation-prone proteins, several of which cluster around elongation factor 2 (eEF-2), a regulator of ribosomal translocation and energy coupling. Cross-species integration defined a network in which eEF-2 links chaperones, metabolic enzymes, and RNA-binding proteins that co-aggregate in both human Alzheimer material and nematode models. Functional tests …

Toward Understanding Multi-Agent Decision Making In Complex Societies, Jonathan Skaggs

Theses and Dissertations

This dissertation investigates Multi Agent Decision Making (MADM) within Complex Societies (CS), systems of interdependent agents whose collective behaviors emerge from local interactions. Such emergent dynamics are nonlinear and difficult to predict, posing significant challenges towards understanding how individual decisions scale to societal outcomes. Existing approaches often fall short of capturing the combined attributes of CS, including asymmetry, decentralization, and adaptivity. To address this gap, we introduce new models and analyses of agent strategies that explain how cooperation and stability can arise in CS. Structured around three interrelated projects, this dissertation enhances our comprehension of MADM in CS. The research …

Towards Resilient Data Governance: An Industry Study On Practitioner Perspectives On The Current State Of Data Governance, Anthony Mazzarella Iii

Theses and Dissertations

Experts agree that data governance is crucial for managing data as an asset, yet in practice, it remains inconsistently defined, unevenly implemented, and poorly understood. Earlier industry studies offered valuable descriptive benchmarks of governance adoption and professional roles, but provided limited theoretical insight and little empirical evidence explaining how governance functions within organizations. Building on this foundation, the current research offers a more substantial and analytically rigorous contribution by transforming descriptive observations into empirical explanations. Through a collaborative academic–industry partnership, the study utilizes a global survey of 565 respondents (348 valid cases) to analyze governance structures, motivations, challenges, and the …

Exploring The Growth Dynamics Of Streptococcus Mutans In Diverse Environmental Conditions, Vanessa Escudero

Theses and Dissertations

Dental caries, a prevalent oral health issue, is primarily associated with the growth of Streptococcus mutans, a Gram-positive bacterium that grows under various oral environments. The primary objective of this study was to evaluate the impact of different beverages and mechanical cleaning on the growth of S. mutans, which plays a crucial role in tooth decay. Using a nano-spectrophotometer we analyzed bacterial growth by constructing growth curves under different conditions, including exposure to cranberry juice, Hawaiian juice, and mechanical brushing.

The study was designed to mimic real-world oral conditions by testing S. mutans in four distinct environments. First, we established …

Elucidating The Oxidation Mechanisms In Cr2alb2 Using Density Functional Theory And Thermodynamic Modeling, Ushan Asela Adhikarige

Theses and Dissertations

This thesis investigates the oxidation behavior of Cr2AlB2 surfaces using density functional theory calculations combined with thermodynamic modeling. Our analysis encompassed surface stability assessments, oxygen adsorption studies on various surfaces, and thermodynamic insights into oxidation mechanisms. Surface stability assessments reveal that the (010) surface terminated with an Al layer exhibits the lowest surface energy. Oxygen adsorption studies on the (010), (111), and (021) surfaces demonstrate strong dissociative adsorption with binding energies ranging from -4.72 to -4.22 eV depending on coverage. Thermodynamic analysis shows that elevated temperatures reduce oxidation favorability, while increased oxygen partial pressure enhances it. The study reveals that …

A Climatology Of Northern Plains Tornadoes With Regard To Radar Coverage, Charles Richie Ii

Theses and Dissertations

Tornadoes are among the costliest and deadliest severe weather events in the United States. Doppler weather radar is one of a meteorologist’s most useful tools for early detection of tornadoes. However, there are several notable areas across the Northern Plains (Minnesota, Montana, North Dakota, and South Dakota) where the National Weather Service’s (NWS) radar coverage exceeds 10,000 feet above radar level, leaving an effective “radar gap” where tornado detection becomes increasingly challenging, if not impossible in some cases. Even within these radar gaps, the NWS is still responsible for issuing Tornado Warnings to fulfill their mission of protecting life and …

Impacts Of Intensifying Wildfires On Boreal Forest Ecosystems: Exploring Forest Regeneration, Wildlife Habitats, Carbon Storage, And Engineering Solutions, Mckenzie Belle Schewe

Theses and Dissertations

Wildfire activity across Alaska’s boreal forests has intensified in severity and frequency in recent decades, altering one of Earth’s most significant sources of carbon sequestration (Pan et al, 2011). This thesis examines how wildland burns influence post-fire carbon sink capacities and vegetation recovery near Fairbanks, Alaska. Three fire sites were selected to represent distinct successional stages: the 2006 Parks Highway Fire, the 2013 Stuart Creek 2 Fire, and the 2022 Clear Fire. Each site was evaluated through a combination of remote sensing analysis, LiDAR-derived canopy height data, and field measurements collected within each burn perimeter, developing a replicable framework for …

Beyond Binaries, Bridging Divides: Centering Identity, Resistance, And Educational Justice Along The Texas-Mexico Border. A Critical Autoethnography Of Underrepresented Intersectionality, Invisibility, And Transformation In Education, Alexander Hernandez

Theses and Dissertations

This dissertation employs solo autoethnography and counter-storytelling to examine how intersecting identities, queer, neurodivergent, bilingual, and fronterizo, shape lived experiences within U.S. educational spaces along the Texas–Mexico border. Grounded in Critical Race Theory as a historical foundation and guided by the braiding logic of Intersectionality (Crenshaw, 1989), the study integrates Latino Critical Race Theory (LatCrit), Disability Critical Race Studies (DisCrit), and Queer Theory to analyze how race, language, ability, and sexuality converge within systems of schooling.

Using memory-work, poetic autoethnography, and narrative vignettes as primary data, the dissertation traces how educational institutions discipline identity through racio-linguistic policing, behavioral surveillance, and …

Feed Network Design For Passive Beamforming In Hemispherical Phased Arrays, Daniel Flores

Theses and Dissertations

This thesis presents the design, fabrication, and evaluation of a four-element microstrip patch antenna array with a passive 1 to 4 corporate feed network operating at 5 GHz. A single inset-fed patch was developed on Rogers DiClad 880 to ensure accurate tuning and mechanical flexibility, achieving a measured resonance of 5.009 GHz with excellent return loss. The corporate feed network, synthesized using T-junction dividers and quarter-wave transformers, demonstrated strong impedance matching, balanced amplitude distribution, and broadside realized gain near 10 dBi when integrated with the array.

Beam steering was examined through simulation-based phase control, revealing effective scanning up to approximately …

Computational Expressions Of Void Reactions In Extended Chemical Reaction Network Models, Aiden J. Massie

Theses and Dissertations

Chemical Reaction Networks (CRNs) are a system of abstraction of real-world chemical dynamics. Each CRN system is defined as a pair of molecular species and reaction rules, which consume a set of reactant species and create a new set of product species. In this paper, we investigate the simple class of void reactions, which cannot create new species and are computationally weak with small-enough sizes in basic CRNs. Here, we study their computational expression in more powerful extended CRN models. Specifically, we consider the Step CRN model, in which new species are added into the system through a sequence of …

Spaceflight Safety Regulations: The Case For Implementing Safety Management Systems In The Developing U.S. Commercial Human Spaceflight Industry, Carly Davidson

Theses and Dissertations

Accidents have historically accompanied the development of new transportation systems, often due to technical failures; but human factors – such as organizational culture and management decisions – are increasingly recognized as significant contributors. A strong safety culture, prioritizing safety at all organizational levels, effective management procedures, and open reporting of violations, is believed to improve outcomes by proactively reducing risk in highly technical organizations. These elements form the basis of Safety Management Systems (SMS), which include safety policy, risk management, assurance, and promotion. As commercial spaceflight expands public access to space, US regulators must develop flexible safety regulations that protect …

Cross Cancer Toxicogenomic Modeling Of Arsenic Exposure Identifies A Four Gene Signature For Lung Cancer Risk, Joshua Kennedy

Theses and Dissertations

Arsenic is a naturally occurring carcinogenic element linked to DNA damage via reactive oxidation and epigenetic alteration that is ubiquitous throughout nature and has been associated with oncogenesis in the lungs, bladder, skin, and liver. Lung Cancer is both the most diagnosed cancer worldwide and the deadliest, comprising approximately 12.4% of all cancers globally and contributing to more human cancer death than any other condition, with roughly 90% of cases arising due to tobacco smoking, which exposes the user to arsenic trioxide and synergistic carcinogenicity when exposure includes both smoking and consumption of arsenic-contaminated drinking water. A novel set of …

Methane Infusion Improved Oil Recovery In The Bakken Formation, Demetrius Maxey

Theses and Dissertations

This research establishes methane infusion improved oil recovery (MI IOR) as a technically viable and economically attractive early-stage intervention for unconventional reservoirs. Integrated multi-scale investigations included quantum molecular theory, nanoscale characterization, NMR experimentation, and field scale reservoir simulation. FEG-SEM analysis of core samples enabled development of a peer-reviewed pore size classification system informing MI operational design parameters. Integrated well logging quantified petrophysical properties across the Bakken stratigraphy. NMR relaxometry identified the lab-scale pore-level sweep efficiency of MI at 3,750 psi in Bakken core samples. Mobilization of hydrocarbons from Np1, Np2, and Np3 pores yielded recovery factors of 45-60%. Field-scale reservoir …