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Studying The Hidden Heat: A Theoretical Approach To Better Understanding The Thermal Conditions Of The Yellowstone Volcano In Wyoming, Usa, Daniel Burke Brunson May 2026

Studying The Hidden Heat: A Theoretical Approach To Better Understanding The Thermal Conditions Of The Yellowstone Volcano In Wyoming, Usa, Daniel Burke Brunson

Theses and Dissertations

Using the spatiotemporal record of the 2.1–0 Ma ignimbrite flare-up of the Yellowstone Plateau Volcanic Field (YPVF) as a proxy for batholith formation at depth, this dissertation develops and applies the Finite Difference Heat Flow Simulation (FDHFS) program to model crustal thermal evolution beneath the supervolcano. FDHFS, a modular C++ numerical simulator, solves the transient heat equation incorporating variable thermal conductivity, radiogenic heat production, and directional advection in three-dimensional Cartesian grids. Validation against analytical benchmarks and seafloor-spreading analogs confirms its fidelity for combined conduction-advection processes in heterogeneous crustal settings.

High-resolution volume–time analysis of major ignimbrite pulses (Huckleberry Ridge, Mesa Falls, …


Modeling Melt Season Snow And Ice Albedo Based On Calibration With Climatological And Physiographic Data In The Wind River Range, Wyoming, Logan Dietrich May 2026

Modeling Melt Season Snow And Ice Albedo Based On Calibration With Climatological And Physiographic Data In The Wind River Range, Wyoming, Logan Dietrich

Theses and Dissertations

Glaciers in high mountain regions are the source of critical water supply for a large portion of the global population, providing freshwater for several uses such as agriculture, irrigation, drinking water, energy production, and the economy. Climate change is causing the increased melting of mountain glaciers, and in turn putting constraints on several of the aforementioned uses of freshwater that is sourced from high mountain regions as well as increasing the risk of natural disasters such as mudslides and glacial lake outburst floods. Understanding the factors that influence glacial melt is important when assessing the mass balance of glaciers and …


Safety Assurance In A Collegiate Flight Program With Safety Management Systems (Sms): A Mixed-Methods Approach To Evaluating Safety Risk Control Effectiveness, Erin Dunker May 2026

Safety Assurance In A Collegiate Flight Program With Safety Management Systems (Sms): A Mixed-Methods Approach To Evaluating Safety Risk Control Effectiveness, Erin Dunker

Theses and Dissertations

This study examined safety assurance and the effectiveness of safety risk controls within a collegiate flight training program operating under a Safety Management System (SMS). Using a mixed-methods approach, the research integrated quantitative survey data with organizational safety performance data to evaluate how safety risk controls function across operational domains. A survey instrument, the Collegiate Aviation Safety Risk Control Effectiveness Scale (CASRICES), was developed and validated to measure perceptions of safety risk control effectiveness among respondents using Exploratory Factor Analysis (EFA), Reliability, and Construct Validity Analyses.

The EFA supported a three-factor structure consisting of Pilot Training Risk Controls, Safety Reporting …


Strengthening Teacher Retention Through Strategic Onboarding, Stacey Eger-Converse May 2026

Strengthening Teacher Retention Through Strategic Onboarding, Stacey Eger-Converse

Theses and Dissertations

The United States education system is currently facing a critical staffing crisis characterized by dwindling enrollment in teacher preparation programs and alarming rates of voluntary attrition. Each school year, school districts report difficulties filling certified positions. This cycle of departure incurs staggering fiscal costs and creates a "recursive loop" where high turnover leads to lower student performance and community dissatisfaction, which further drives teacher exits. While most new teachers participate in induction programs, districts continue to lose approximately half of their new hires, suggesting that current support structures are insufficient. This research addresses a significant gap in the literature: the …


The Speech, Language, And Feeding Development Of One Child With Wiedemann–Steiner Syndrome, Alyssa Ann Erickson May 2026

The Speech, Language, And Feeding Development Of One Child With Wiedemann–Steiner Syndrome, Alyssa Ann Erickson

Theses and Dissertations

This thesis examines the longitudinal speech, language, and feeding development of a child with Wiedemann–Steiner syndrome (WSS) from birth to age 10. The study aimed to characterize developmental patterns, identify strengths and challenges, and evaluate changes over time within the context of ongoing speech-language intervention. A qualitative longitudinal case study design was used, combining retrospective review of medical, therapeutic, and educational records with direct clinical assessment at age 10. Measures included the Oral and Written Language Scales–Second Edition (OWLS-II)), a spontaneous language sample, a phonemic inventory, a Childhood Apraxia of Speech screening, a caregiver feeding questionnaire, and a clinical feeding …


Modeling Type 2 Diabetes Progression, Hereditary Risk, And Treatment Outcomes: Integrating Prevention, Lifestyle Modifications, And Pharmacological Interventions, Grace Ebunoluwa Fatoyinbo May 2026

Modeling Type 2 Diabetes Progression, Hereditary Risk, And Treatment Outcomes: Integrating Prevention, Lifestyle Modifications, And Pharmacological Interventions, Grace Ebunoluwa Fatoyinbo

Theses and Dissertations

Type 2 diabetes (T2D) remains one of the most significant chronic health conditionsworldwide and continues to place pressure on healthcare systems through its long-term complications, treatment costs, and growing prevalence. The progression of T2D is influenced by multiple interacting factors, including hereditary predisposition, lifestyle behavior, treatment access, remission, relapse, and the development of complications. Because of this complexity, mathematical models can provide useful insight into disease dynamics and the possible effects of intervention strategies over time. This study develops a compartmental model for T2D progression using a system of ordinary differential equations. The population is divided into epidemiologically meaningful classes …


Numerical Verification Of A Gpu-Accelerated Particle-In-Cell Code For Low-Temperature Plasma Simulations, Wei Guo May 2026

Numerical Verification Of A Gpu-Accelerated Particle-In-Cell Code For Low-Temperature Plasma Simulations, Wei Guo

Theses and Dissertations

This thesis presents the numerical verification of Comet, a GPU-accelerated Particle-in-Cell with Monte Carlo Collisions (PIC/MCC) code designed for low-temperature plasma simulations. To ensure efficient deployment across heterogeneous computing architectures, the framework leverages the Kokkos performance-portability layer for high-performance execution. Verification was conducted through a series of hierarchical stages with increasing physical complexity, benchmarking each component of the fundamental PIC/MCC simulation cycle. This structured approach establishes the numerical fidelity of the code's algorithmic building blocks prior to its application in predictive plasma research.

The first stage verifies field interpolation and particle pusher modules against canonical single-particle cases, focusing on ion …


Bridging Culture And Education To Enhance Cherokee Student Health And Wellness, Lindsey Hammer May 2026

Bridging Culture And Education To Enhance Cherokee Student Health And Wellness, Lindsey Hammer

Theses and Dissertations

Indigenous populations face ongoing health disparities, often worsened by a lack of culturally relevant and Indigenous-led programs and interventions. This dissertation in practice was inspired by the need for community-driven, culturally grounded approaches that address these disparities for Cherokee Nation in Northeastern Oklahoma. Each of the three products are inspired by and aligned with the principles of Community-Based Participatory Research (CBPR), the Cherokee value of gadugi, and the concept of relationality, offering a holistic approach to community health and well-being. Not every product represents a fully implemented CBPR process but rather a CBPR-informed approach. Future stages will emphasize more meaningful …


Machine Learning For Laminar Heat Transfer In Supercritical Fluids, Luke Holtshouser May 2026

Machine Learning For Laminar Heat Transfer In Supercritical Fluids, Luke Holtshouser

Theses and Dissertations

In the last 10 years machine learning has become increasingly more used in the field of fluid dynamics and heat transfer. However, with this increase in activity, gaps still exist with respect to supercritical fluids and laminar flows, where laminar flow in general seems understudied. For supercritical fluids, there are many peculiar studies that are isolated to unique systems or they are obscure enough to include everything but the kitchen sink. This strategy provides no real insights into how the field can make further progress in the utilization of the technology available, or rather build-upon previous knowledge. For this reason, …


Critical Minerals Recovery From Oil And Gas Fields Produced Water In The Bakken Formation, North Dakota, Md Jakaria May 2026

Critical Minerals Recovery From Oil And Gas Fields Produced Water In The Bakken Formation, North Dakota, Md Jakaria

Theses and Dissertations

The growing demand for critical minerals essential to clean energy technologies presents an opportunity to transform oilfield produced water (PW) – traditionally treated as waste – into a valuable resource. This dissertation investigates the recovery potential of lithium, salts, and other critical elements from produced water in the Bakken Formation, North Dakota, and evaluates the economic feasibility of integrating such recovery processes into existing petroleum operations. Comprehensive geochemical analyses were conducted on samples collected throughout the Bakken, revealing total dissolved solids (TDS) ranging from 46,815 to 327,714 ppm and lithium concentrations exceeding 200 ppm in several wells, indicating economically recoverable …


A Life Cycle Assessment Of Cotton And Hemp As Textile Fibers, Emalie Johnson May 2026

A Life Cycle Assessment Of Cotton And Hemp As Textile Fibers, Emalie Johnson

Theses and Dissertations

Garment consumption is on the rise. With an increase in resource use, there will beobservable impacts. This study focused on the environmental impacts from garment production, specifically from natural fibers – cotton and hemp. Using the program SimaPro, a life cycle assessment (LCA) was conducted from cradle to consumer. The LCA included fiber cultivation, textile production, and consumer use phase for a t-shirt, one made from cotton and one made from hemp. A survey was distributed among the University of North Dakota’s student and faculty population to gather data on consumer use behaviors, including shopping, laundry, and discard habits. The …


Redox-Driven Wettability In Underground Hydrogen Storage: Linking Geochemical Speciation, Surface Charge, And Contact Angle, Ijaz Khan May 2026

Redox-Driven Wettability In Underground Hydrogen Storage: Linking Geochemical Speciation, Surface Charge, And Contact Angle, Ijaz Khan

Theses and Dissertations

Underground hydrogen storage (UHS) depends on complex interactions among reservoir rocks, brine, and gas under redox conditions induced by H2 injection. Although wettability is often treated as a static parameter, redox reactions can shift pH, aqueous speciation, and mineral surface charge, thereby altering contact angles and, consequently, injectivity, trapping, and recovery. This work tests the hypothesis that dominant redox pathways in saline aquifers and depleted reservoirs, specifically Fe(III) and sulfate reduction, systematically modify mineral surface stability and charge, producing predictable shifts in wettability. To address this, we developed a physics-guided machine learning workflow that integrates mechanistic geochemical understanding with empirical …


Self-Talk In Esports: Extending Sport Psychology Frameworks To Digital Competition, Brett Anne Thompson Machamer May 2026

Self-Talk In Esports: Extending Sport Psychology Frameworks To Digital Competition, Brett Anne Thompson Machamer

Theses and Dissertations

Self-talk is a key mechanism underlying performance, confidence, and emotional regulation, yet its use in esports remains underexplored. This study examined self-talk patterns among esports players, focusing on associations with hours played, self-talk type and valence, and contextual and motivational factors influencing its use. Esports players (N = 102; M = 18.53 hours/week, SD = 13.74) across a range of competitive levels completed an online questionnaire assessing self-talk type, valence, and contextual use. Greater hours played were associated with increased use of strategic self-talk, while self-talk valence was not significantly related to time spent playing. Participants most frequently reported using …


Flipping The Odds: At-Risk Students’ Perceptions Of The Benefits Of The Flipped Classroom Model In High School Mathematics, Roberto Alonzo Moedano May 2026

Flipping The Odds: At-Risk Students’ Perceptions Of The Benefits Of The Flipped Classroom Model In High School Mathematics, Roberto Alonzo Moedano

Theses and Dissertations

High school educators tasked with teaching and learning are often challenged to find ways to keep students engaged and ensure they are learning content. However, the COVID-19 pandemic that the United States experienced from 2020 to 2023 (Northwestern Medicine Staff & Northwestern Medicine, 2025) made educators’ efforts more difficult. This unprecedented time of remote teaching and learning transformed the educational landscape overnight. It removed face-to-face learning and replaced it with virtual classes—neither teachers nor students were prepared for the challenges. This research study examines how a flipped classroom approach has the potential to yield positive results at the high school …


Evaluation Of Geothermal Viability In Partially Abandoned And Dry Oil Wells Within The Red River Formation In Williston Basin For Repurposing Into Enhanced Geothermal Systems, Ajan Meenakshisundaram May 2026

Evaluation Of Geothermal Viability In Partially Abandoned And Dry Oil Wells Within The Red River Formation In Williston Basin For Repurposing Into Enhanced Geothermal Systems, Ajan Meenakshisundaram

Theses and Dissertations

Transitioning toward global decarbonization of energy resources necessitates the development of dispatchable baseload resources that leverage existing infrastructure to minimize environmental footprints and capital expenditures. This research investigates the technical and economic feasibility of repurposing unplugged and dry oil and gas wells within the Red River Formation of the Williston Basin in North Dakota for conversion into Enhanced Geothermal Systems (EGS). While immense geothermal resources exist, they are often rendered uneconomical by high drilling costs and a lack of holistic subsurface understanding at target depths. To bridge these gaps, this interdisciplinary study employs a workflow ranging from experimental physics and …


Thriving Within Digital Learning Courses: Examining The Influence Of Interactions In Kinesiology Undergraduate Students, Jimmy J. Morin May 2026

Thriving Within Digital Learning Courses: Examining The Influence Of Interactions In Kinesiology Undergraduate Students, Jimmy J. Morin

Theses and Dissertations

The expansion of online and hybrid education has reshaped higher education, particularly in applied fields such as kinesiology that emphasize hands-on learning. Despite this growth, limited research has examined how specific interaction types (academic, social, and deeper life) contribute to student thriving in digital environments. This dissertation explored how interactions with faculty, staff, and peers influence holistic student success in online and hybrid kinesiology programs utilizing a three-paper dissertation approach to address this gap through complementary methods. Paper 1 synthesizes existing literature on student interactions and thriving in digital learning contexts. Paper 2 uses one-way ANOVA and ANCOVA to examine …


Filling The Gaps: Rural-Remote High School Teachers’ Perceptions Of Professional Training In Student Mental Health Preparedness, Angela N. Muhs May 2026

Filling The Gaps: Rural-Remote High School Teachers’ Perceptions Of Professional Training In Student Mental Health Preparedness, Angela N. Muhs

Theses and Dissertations

Rural-remote high school teachers are frequently the first to notice and respond to student mental health concerns, yet they operate within communities characterized by significant shortages in mental health providers. Access to professional mental health services in these settings remains persistently limited, placing considerable responsibility on teachers who may lack adequate preparation. This study employed an interpretive case study design to qualitatively examine how rural-remote high school teachers in North Dakota perceive their professional training and overall preparedness in addressing student mental health concerns. Twelve licensed teachers, whose experience ranged from six months to 33 years, participated in in-depth interviews. …


A Privacy-Preserving, Ai-Driven Framework For Bathroom Activity Monitoring And Health Recommendation In Elderly Care, Collins Poku Obeng May 2026

A Privacy-Preserving, Ai-Driven Framework For Bathroom Activity Monitoring And Health Recommendation In Elderly Care, Collins Poku Obeng

Theses and Dissertations

The rapid aging of the global population necessitates scalable, non-invasive solutions, for monitoring Activities of Daily Living (ADLs) to detect early signs of health decline. This thesis presents a novel, end-to-end framework for monitoring bathroom activities—specifically bathing, toileting, and oral hygiene—using wearable sensors, machine learning and Agentic Artificial Intelligence (AI). The research addresses three critical gaps: the lack of granular activity recognition in privacy-sensitive spaces, the need for personalized health insights without manual logging, and the cybersecurity risks inherent in deploying AI in healthcare. First, algorithms utilizing wearable humidity and accelerometer sensor data were developed to classify hygiene behaviors with …


Identifying Diet Quality Of Ultra-Processed Foods Among Student Health Professionals, Claudia Julianne Promschmidt May 2026

Identifying Diet Quality Of Ultra-Processed Foods Among Student Health Professionals, Claudia Julianne Promschmidt

Theses and Dissertations

Disagreement exists in literature and media on definitions and classification ofultra-processed food (UPF) making interpretation for policy makers, consumers, and health professionals confusing. As health professionals have a large role in nutrition education, this study looked at how students enrolled in a health professional program at the University of North Dakota determine nutrient density of UPFs and non-UPFs. Researchers calculated nutrient density to classify foods into a survey. Students completing the survey had access to both the ingredient list and Nutrition Facts Panel before selecting the food as choose often, sometimes, or rarely, and then indicated which tool was used …


Ground Penetrating Radar Spiral Antenna Transient Response Based On Target Radar Cross Section, David Rohde May 2026

Ground Penetrating Radar Spiral Antenna Transient Response Based On Target Radar Cross Section, David Rohde

Theses and Dissertations

This dissertation presents a significant advancement in Ground Penetrating Radar (GPR) detection technology through the development of a novel method for the detection and classification of buried conductive objects using custom-designed Archimedean spiral antennas. The research demonstrates that the transient electromagnetic response of an Archimedean spiral antenna is strongly correlated with the Radar Cross Section (RCS) characteristics of buried objects operating within the radar resonance scattering, or Mie, region. By leveraging this relationship, the proposed approach enables not only the detection of buried objects, but also generalized classification based on object geometry and size.A primary contribution of this work is …


An Environmental Systems Engineering Framework For The United States Space Force: Multi-Objective Optimization Of Co2 Emissions And Biodiversity Trade-Offs, Julio Roberto Pinto Covelli May 2026

An Environmental Systems Engineering Framework For The United States Space Force: Multi-Objective Optimization Of Co2 Emissions And Biodiversity Trade-Offs, Julio Roberto Pinto Covelli

Theses and Dissertations

The increasing demand for sustainable defense operations has prompted the US Space Force to explore advanced strategies that reduce carbon emissions and preserve biodiversity across its installations. This dissertation proposes a scalable systems-engineering framework that quantitatively integrates CO₂ emissions modeling and ecological simulation at RAF Feltwell and RAF Lakenheath, two strategically signi?cant installations with notable ecological value. Using toolsincluding Python, MATLAB, ArcGIS, and InVEST, this research models emissions and habitat quality under various operational scenarios. The study incorporates engineering performance metrics, including emissions intensity, resilience indicators, and energy efficiency rates, to inform trade-off modeling for real-time mission and environmental decision-making. …


Spirituality And Well-Being Among Native College Students, Emma Reese Smith May 2026

Spirituality And Well-Being Among Native College Students, Emma Reese Smith

Theses and Dissertations

In the current literature surrounding spirituality, definitions and conceptualizations of the construct differ. Researchers have proposed common themes of spirituality–self-awareness, interconnectedness to the world, and a relationship to a higher power or greater purpose (Hamilton & Jackson, 1998). While definitions of spirituality and how it is operationalized vary across studies, the current view in the field is that spirituality has positive outcomes on those who practice it, including their overall degree of well-being. While these positive effects have been showcased in the literature, due to the influence of western Christian perspectives on many measures of spirituality, there are methodological issues …


Beyond The Manual: Training Troubleshooting Skills Through Augmented Reality, Lawrence Allen Smith Jr. May 2026

Beyond The Manual: Training Troubleshooting Skills Through Augmented Reality, Lawrence Allen Smith Jr.

Theses and Dissertations

Many industrial maintenance departments implement and utilize Augmented Reality Technology (ART) and Augmented Reality Technical Training (ARTT) in their day-to-day operations. This study aims to examine technicians' troubleshooting skills by exploring two main questions: (1) how these skills are impacted by Cognitive Load Theory (CLT), and (2) how they are influenced by using either paper manuals or ARTT manuals. The research will compare the effects of traditional paper manuals and ARTT manuals on the learning outcomes of troubleshooters. The measurements of learning outcomes will include cognitive ability, professional specific knowledge, and skill retention. Keywords: augmented reality (AR), industrial maintenance, augmented …


Predicting Diversity Gaps In Clinical Trials Using Digital Twin Modeling, Abigail Tubbs May 2026

Predicting Diversity Gaps In Clinical Trials Using Digital Twin Modeling, Abigail Tubbs

Theses and Dissertations

Demographic underrepresentation in clinical trials continues to limit the external validity, equity, and generalizability of biomedical evidence. While regulatory reforms have increased the availability of aggregate demographic reporting, most existing approaches assess representation retrospectively, after recruitment has begun, offering limited support for design-stage decision-making. This dissertation presents a digital twin–based framework for prospective assessment of demographic diversity in clinical trials using trial-level metadata. The work integrates three core contributions. First, an open, reproducible, no-code extraction tool was developed to enable bulk retrieval and harmonization of baseline demographic data (race, ethnicity, sex/gender, and age) from ClinicalTrials.gov using National Clinical Trial identifiers. …


Enhancing Geothermal Productivity In The Red River Formation, Williston Basin: Utilization Of Unconventional Stimulation Technology And Sco2 Injection To Improve Geothermal Inlet Temperature, Fluid Flow Rate, And Project Economics, Etochukwu Jude Uzuegbu May 2026

Enhancing Geothermal Productivity In The Red River Formation, Williston Basin: Utilization Of Unconventional Stimulation Technology And Sco2 Injection To Improve Geothermal Inlet Temperature, Fluid Flow Rate, And Project Economics, Etochukwu Jude Uzuegbu

Theses and Dissertations

Geothermal energy is a reliable renewable energy source capable of delivering consistent baseload electricity while emitting very low concentrations of greenhouse gases. In very low permeable geothermal reservoir, the geothermal system’s efficiency and economic feasibility are heavily dependent on reservoir productivity, which includes the fluid circulation and heat extraction efficiency. This research assesses the geothermal inlet temperature dynamics, fluid production and techno-economic viability of two reservoir productivity enhancement approaches: Hydraulic Fracturing (Base Case model) and Fishbones stimulation (Proposed Case model) under various operational conditions. The research aims to evaluate the influence of these two approaches on the geothermal inlet temperature, …


Unified Deep Learning Techniques For Spatial Detection And Temporal Forecasting Across Visual Domains, John Olawale Olamofe May 2026

Unified Deep Learning Techniques For Spatial Detection And Temporal Forecasting Across Visual Domains, John Olawale Olamofe

All Dissertations

This dissertation proposed a unified deep learning framework for spatial detection and temporal forecasting across visual domains, designed to address limited supervision, class imbalance, and scale variability. The framework was structured around four complementary principles: Domain-Aware Input Rebalancing, Representation-Centric Learning, Diversity-Driven Robustness, and Transfer Across Scale and Modality, which together enabled robust visual representation learning across heterogeneous data sources.

Domain-Aware Input Rebalancing mitigates non-uniform and sparse data distributions by actively reshaping inputs before learning via class-aware augmentation, sampling, resolution manipulation, and super-resolution. This principle underpins object detection in overhead satellite imagery (xView), dense urban aerial scenes (CADOT), temporally sparse NDVI …


Software Integration In Personal Healthcare Devices And The Patient User Experience, Yassine Chahid, Patrick Slattery May 2026

Software Integration In Personal Healthcare Devices And The Patient User Experience, Yassine Chahid, Patrick Slattery

Publications and Research

This study examines the current landscape and future direction of medical device hardware and software integration, focusing on how each contributes to patient care. It begins by analyzing hardware focused medical devices, such as implantable tools patients may rely on to assist with their condition, alongside diagnostic and monitoring equipment used to treat conditions in a variety of medical areas (e.g. cardiovascular conditions). It then evaluates how software is currently integrated through embedded systems, data processing, and user interfaces that support real time monitoring and clinical decision making, and how this impacts quality of care for the patient whilst minimizing …


Molecular Mechanisms Of Pfas Induced Protein Dysfunction: Implications For Neurodegenerative Risk, Daisy Lee Wilson May 2026

Molecular Mechanisms Of Pfas Induced Protein Dysfunction: Implications For Neurodegenerative Risk, Daisy Lee Wilson

Open Access Theses & Dissertations

Per- and polyfluoroalkyl substances (PFAS) are persistent environmental contaminants with widespread human exposure and well-established links to adverse health outcomes. However, despite increasing epidemiological and experimental evidence, the molecular mechanisms underlying PFAS-induced neurotoxicity remain incompletely defined. This dissertation investigates PFAS toxicity across biological scales, integrating protein biophysics with neuronal cell models to elucidate pathways relevant to neurodegeneration. At the molecular level, we demonstrate that PFAS disrupts the structure and function of globular proteins, including the impairment of α-lactalbumin's calcium-binding capacity and of β-lactoglobulin's retinol binding, through concentration-dependent conformational destabilization. By applying these findings to a neuronal model, we show that …


Riemannian Manifold-Coupled Joint Sparse Graphical Models For Spatially Structured Precision Matrix Estimation, Abdul Rahman Adam May 2026

Riemannian Manifold-Coupled Joint Sparse Graphical Models For Spatially Structured Precision Matrix Estimation, Abdul Rahman Adam

Open Access Theses & Dissertations

This thesis introduces a novel geometry-aware framework for joint precision matrix estimation in spatially structured data. Unlike existing joint Gaussian graphical model estimators that rely on Euclidean coupling mechanisms such as fused or group graphical lasso, our approach incorporates intrinsic Riemannian geometry through geodesic distance penalties on the symmetric positive definite manifold.

The method measures similarity between precision matrices of adjacent spatial regions using the affine-invariant Riemannian distance, capturing deformations of concentration ellipsoids rather than entrywise differences. This is particularly suited for spatial transcriptomics, where regions may share dependence structures despite differences in scale or composition.

An efficient Alternating Direction …


A Systems Engineering-Based Method For Enabling Digital Transformation In A Binational Small Healthcare Enterprise, Manuel Adrian Alvarez Ramirez May 2026

A Systems Engineering-Based Method For Enabling Digital Transformation In A Binational Small Healthcare Enterprise, Manuel Adrian Alvarez Ramirez

Open Access Theses & Dissertations

The year 2020, often described as "the great accelerator" for emerging technologies, marked a period of significant transformation in lifestyles, work patterns, and business strategies. For instance, online meetings have become more convenient than in-person interactions, even with colleagues in neighboring offices. For small businesses, rapid regulatory and technological changes required swift adaptation, including the acquisition of new technologies, tools, and software to ensure survival. This transition also necessitated adopting indirect engagement, revising communication protocols, and digitally transforming information. Small and Medium-sized Enterprises (SMEs) in essential service sectors face also a fundamental paradox: their dependence on the skills, relationships, and …