Physical Sciences and Mathematics Commons^™

Tunable Physical Color In Nanostructured Materials: Exploring Reversible Mechanisms For Active Optical Control, Matt Hughes

Chemistry & Biochemistry Undergraduate Honors Theses

Vanadium Dioxide (VO₂) thin films have been grown on silicon wafers using atomic layer deposition of TDMAV (tetrakis(dimethylamino)vanadium(IV)) and H₂O as precursors. A quartz crystal microbalance (QCM) measurement was used during deposition to confirm growth and resulted in a growth rate of approximately 0.6 Angstroms/cycle. X-Ray Reflectivity (XRR) was performed to confirm growth thickness and reported an approximately 30 nm thin film after 500 cycles of TDMAV precursor deposition. X-Ray photoelectron spectroscopy was utilized to determine the phase of the vanadium samples and confirmed the presence of vanadium dioxide as prepared and after annealing under nitrogen …

Sequential Products Of Anaerobic Denitrification In Calcareous And Noncalcareous Soils By Use Of The Gas Chromatograph, Grant S. Cooper

All Graduate Theses and Dissertations, Fall 2023 to Present

The sequential products of anaerobic denitrification were determined on seven Western soils (four alkaline, two acid, and one neutral) by soil and gas analysis. The soils with 1% alfalfa and added KNO3 were incubated at moistures slightly greater than field capacity and with an atmosphere of He. The soils and gases were periodically analyzed and balance sheets prepared. The sequence of NO3-->NO2-->N2O-->N2 operated in all soils. The rates of nitrogen interchanges and maximal amounts of nitrate, N2O2 and N2 were determined. From this data it was postulated that the rate-limiting process for denitrification in acid soils is …

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 …

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 …

St-Fmformer: An Autoregressive Generation Framework For Scientific Ensemble Data Predictions, Md Robiul Islam

All Graduate Theses and Dissertations, Fall 2023 to Present

Understanding how physical systems change over time is important in areas such as weather prediction, fluid dynamics, and environmental science. However, accurately predicting future behavior is difficult because these systems are complex and constantly evolving. 

This research develops a deep learning approach to predict how such systems evolve over time. The model learns patterns from past observations and uses them to generate future states step by step. This provides a faster alternative to traditional simulation methods while maintaining strong predictive performance. 

The proposed method focuses on improving the consistency of predictions over time and is designed to work across different …

Fixed Perimeter Analogues Of Some Partition Results, Gabriel Gray, Emily Payne, Holly Swisher, Ren Watson

School of Mathematical & Statistical Sciences Faculty Publications

Euler's partition identity states that the number of partitions of n into odd parts is equal to the number of partitions of n into distinct parts. Strikingly, Straub proved in 2016 that this identity also holds when counting partitions of any size with largest hook length (perimeter) n. This has inspired further investigation of partition identities and inequalities in the fixed perimeter setting. Here, we explore fixed perimeter analogues of some well-known partition results inspired by Euler's partition identity.

A Novel Approach To Creativity Assessment: Forced Pairwise Ranking With Large Language Models, Phillip R. Gregory Jr

Master's Theses

Assessing creativity at scale remains a persistent challenge in cognitive science, as human raters are costly, slow, and often inconsistent in their judgments. This thesis introduced a novel framework for automated scientific creativity assessment using forced pairwise ranking, in which fine-tuned large language models compared response pairs and determined which was more creative. Five empirical studies were conducted using Llama-2-7B and Llama-2-13B models adapted via LoRA fine-tuning and benchmarked against human scored responses from the Scientific Creative Thinking Test. A regression baseline achieved Pearson �� = .74 on the test set, matching the human inter-rater ceiling reported in the literature. …

On The Paleontology Of Belize, Alson Ovando

Electronic Theses and Dissertations

Paleontology can be considered an underrepresented and emerging area of science in Belize. A primary aim of this thesis is to provide a background of paleontology in Belize and present the first comprehensive study of Quaternary vertebrate fossils known from the country. Quaternary fossil sites across Belize include caves, rivers, and sinkholes. In addition to reviewing and assessing material from known sites, this thesis presents new information and discoveries that were made while investigating Belize’s Quaternary fossil record. This thesis also includes a geospatial model depicting ecoregions in Belize during the last glacial maximum. Overall, the results presented here demonstrate …

Environmental And Structural Drivers Of Hurricane Edouard (2014) Intensification, Elizabeth Smith

Atmospheric and Environmental Sciences Honors Program

Forecasting tropical cyclone (TC) intensification remains challenging due to the complex kinematic and thermodynamic processes that control storm evolution. This study examines the structural and environmental changes associated with the intensification of Hurricane Edouard (2014) by analyzing multiple observational datasets during its development. The analysis is divided into four categories: (1) environmental moistening, evaluated using dropsonde and aircraft flight-level data; (2) vortex structure, examining changes in the storm’s circulation and organization; (3) convective structure, assessed through radar and satellite observations; and (4) lightning bursts, using lightning detection data in the storm’s outer and inner rainbands. By comparing the timing of …

Examining Student Practices In A Technology-Mediated Math Classroom, Bradley T. Dodd

Electronic Theses, Projects, and Dissertations

It is important for math educators to make sense of student thinking in the classroom. Without opportunities to practice this skill math educators struggle to improve, particularly when students are engaging in mathematics using technology. As such, there is a need for video artifacts of students engaging with mathematics using technology for use in professional development activities (Lovett 2020). In accordance with Lovett et al.'s (2020) design principles for examining student practices in a technology-mediated environment, I carried out a study to determine whether these artifacts of student work could be created working with college undergraduates as participants. Students engaged …

Improving Fairness On Semantic Segmentation Using Large Language Models, Samuel E. Burggraf

Electrical & Computer Engineering Projects for D. Eng. Degree

As machine learning systems are increasingly integrated into critical decision-making processes, ensuring fairness in their design and implementation has become a significant concern. While fairness research has primarily focused on specific protected attributes, less attention has been given to spatial fairness, which can affect individuals at specific locations. If fairness is not addressed, models may systematically underperform in certain regions or across populations which can lead to unequal access to accurate predictions and potentially biased decision-making. Fairness considerations should extend across all machine learning applications to align with the National Institute of Standards and Technology (NIST) guidelines of fair and …

Quantifying Macrophyte Ecosystem Services And Improving Environmental Nonprofit Messaging, Peyton R. Hughey

All Theses

Environmental nonprofits are essential to the management and restoration of our natural spaces. They are also tasked with engaging the public via outreach, education, and advocacy. As natural spaces are degraded, the ability of environmental nonprofits to deliver on their missions will become increasingly important. This study aimed to improve two approaches to environmental nonprofits’ missions: ecological restoration and social media communication.

Environmental nonprofits operate with limited resources, and ecological restoration can be an exhaustive task; therefore, we explore functional restoration as a tool. In this study, we focus on the use of functional, trait-based restoration to restore ecological function …

Between Chronicle And Legend: A Two-Scene Environment And Visual Effects Examination Of Physical Accuracy And Emotional Exaggeration On The Honey Creek Bridge Collapse, Alison R. Gaddy

All Theses

This thesis explores how truth and dramatization intersect in digital storytelling by comparing realistic and stylized simulations of the Honey Creek bridge collapse within the context of the Kate Shelley animated short. At the core of storytelling lies a tension between factual accuracy and dramatic stylization. We investigate that tension by examining how narrative truth is conveyed, distorted, or enhanced through visual dramatization by focusing on the psychology of audience perception and the motivations behind creative embellishment. The practical contribution of this research is the development of two distinct digital scene setups depicting the same Honey Creek bridge collapse event. …

Energetic Eutectics: An Experimental And Computational Investigation On Explosive Deep Eutectic Solvents, Connor J. Parker

All Theses

This study reports on the incorporation an extreme gradient boosting (XGBoost) machine learning strategy tailored to identifying potential high-energy, insensitive explosive deep eutectic solvents. 1,1-diamino-2,2-dinitroethylene (FOX-7) was investigated as the explosive of interest in our eutectic modeling. The resulting predictions highlighted a wide range of binary compositions demonstrating significant depression from the FOX-7 melting temperature with >70% probabilities of formation. Subsequent computational investigation into select mixtures provided underlying stabilization energies and optimized mixture geometries, which were then assessed experimentally with near simulant compounds oxalyldihydrazide and 1-methyl-3- nitroguanidine replacing FOX-7.

Experimental results with these chosen simulants did not demonstrate classical eutectic …

Low Methane Emissions From Nutrient-Rich Former River Channels In A Hydrologically Managed Dryland Delta, Siena Stassi, Jude A. Benavides, Chu-Lin Cheng, Marcelo Gomes Da Silva, Nicholas E. Ray, Nathan O. Barros, Rafael M. Almeida

School of Earth, Environmental, & Marine Sciences Faculty Publications

Anthropogenic stresses in dryland regions can alter hydrology, salinization, and biogeochemical processes. How these pressures influence methane (CH4) cycling and emissions from aquatic ecosystems remains poorly understood. Over the course of 1 year, we measured diffusive and ebullitive CH4 emissions from resacas—shallow, hydrologically managed distributary channels prevalent throughout the Lower Rio Grande Valley along the US–Mexico border. Despite warm, nutrient-rich waters, CH4 emissions from resacas were low, and more comparable to rates observed in estuarine systems. CH4 fluxes were positively related to temperature but negatively related to salinity and rainfall. Elevated salinity, driven by evaporation and source water from the …

Landscape Connectivity And Wildlife Access To Water Across An International Border: Barriers And Opportunities For Facilitating Transboundary Movement, Bogdan Chivoiu, Erin L. Koen, Michael J. Osland, Christopher A. Gabler, Jerald T. Garrett, Ernesto Reyes, Stephanie A. Bilodeau, Mitch A. Sternberg, Jude A. Benavides, James Martinez

School of Earth, Environmental, & Marine Sciences Faculty Publications

Rapid global acceleration in the construction of physical barriers along international borders has greatly influenced biodiversity and animal movement. Physical barriers can fragment landscapes, hinder access to essential resources, impact long-distance migrations, and inhibit dispersal and gene flow. The effects of physical barriers on animal movement and landscape connectivity can be exacerbated in dryland environments where access to water is a limiting factor. In recent decades, the construction of border barrier infrastructure has accelerated along the international boundary between the United States and Mexico. Here, we used a landscape connectivity model to investigate the effects of barriers on wildlife access …

Optical Counterparts To X-Ray Sources In Lsst Dp1, Yuankun David Wang, Eric Bellm, Robert I. Hynes, Yue Zhao, Poshak Gandhi, Liliana E. Rivera Sandoval, Sandro Campos, Neven Caplar, Melissa Delucchi, Konstantin Malanchev

Physics & Astronomy Faculty Publications

We present a crossmatch between a combined catalog of X-ray sources and the Vera C. Rubin Observatory Data Preview 1 (DP1) to identify optical counterparts. The six fields targeted as part of DP1 include the Extended Chandra Deep Field South (E-CDF-S), the Euclid Deep Field South, the Fornax Dwarf Spheroidal Galaxy (Fornax dSph), 47 Tucanae (47 Tuc), and science validation fields with low Galactic and ecliptic latitude (SV_95_-25 and SV_38_7, respectively). We find matches to 2314 of 3830 X-ray sources. We also compare our crossmatch to DP1 in the E-CDF-S field to previous efforts to identify optical counterparts. The probability …

Pattern Dynamics And Stochasticity Of Brain Rhythms And Spike Trains In A Tauopathy Mouse Model Of Alzheimer’S Disease, Clarissa M. Hoffman

Dissertations and Theses (Open Access)

Systems neuroscience posits that every aspect of perceived physical reality, every aspect of animal and human behavior, and every cognitive phenomenon emerges from patterns of neuronal activity. While most researchers embrace this idea, there are major difficulties in describing and analyzing these complex neuronal dynamics—spike flows produced by cells ensembles, synchronized extracellular field oscillations, and other patterns—which limits our understanding of how the activity of individual neurons and the whole-animal cognition and behavior might be connected. In particular, we lack the approaches and even the semantics for connecting the individual cell outputs and the integrated results of their activity. Current …

Membrane Organization Of Rheb And Rhoa: Roles In Function And Allosteric Druggability, Chase M. Hutchins

Dissertations and Theses (Open Access)

Small GTPases of the Ras superfamily are membrane-bound molecular switches that regulate nearly all major cellular processes, and their dysregulation drives cancers, neurological disorders, and metabolic diseases. While anchored to cellular membranes, the catalytic domains of small GTPases undergo orientation dynamics, adopting distinct configurations that can occlude or expose effector-binding surfaces and modulate signaling output. These dynamics have been characterized in the Ras oncoproteins, but whether they extend across the superfamily and influence allosteric druggability has remained unknown.

In this dissertation, I address these questions through Rheb and RhoA, two small GTPases with complementary differences in subfamily lineage, membrane localization, …

The Impact Of Label Material On Perceived Value And Environmental-Friendliness Of Beverages In Returnable Glass Bottles Versus Actual Environmental Impact Via Life Cycle Assessment, Toni Sharp

All Dissertations

With guidance from the EPA to reduce virgin packaging use and alternatively increase reuse, the concept of reusable packaging has re-emerged as a potential sustainable alternative to single-use and recyclable packaging. For businesses, an understanding of the potential environmental benefits of switching from single-use packaging to reusable packaging, along with consumer willingness to pay for sustainable packaging are paramount. Existing literature on willingness to pay (WTP) for ethical or sustainable products typically relies on consumers’ stated preferences found through surveys using hypothetical products and prices. It has been revealed that sustainability claims printed on the label or products in glass …

Intersectionality And Belonging: Higher Education Mathematics, Ashley Natalie

Mathematics and Statistics

Students with intersecting marginalized identities (such as race, gender, socioeconomic status, disability, or first-generation background) often face unique challenges in advanced mathematics that affect confidence, participation, amounting to a sense of belonging. These experiences remain underrepresented in mathematics education research. This qualitative, narrative-based study examines how these students experience classroom dynamics and belonging in upper-level mathematics courses. Semi-structured interviews will be analyzed thematically to identify patterns related to identity, classroom culture, instructor behavior, and peer interactions. Findings aim to highlight barriers and supportive practices, informing more inclusive teaching strategies and equitable learning environments in advanced mathematics.

Intersectionality And Belonging: Higher Education Mathematics, Ashley Williams

Mathematics and Statistics

Students with intersecting marginalized identities (such as race, gender, socioeconomic status, disability, or first-generation background) often face unique challenges in advanced mathematics that affect confidence, participation, amounting to a sense of belonging. These experiences remain underrepresented in mathematics education research. This qualitative, narrative-based study examines how these students experience classroom dynamics and belonging in upper-level mathematics courses. Semi-structured interviews will be analyzed thematically to identify patterns related to identity, classroom culture, instructor behavior, and peer interactions. Findings aim to highlight barriers and supportive practices, informing more inclusive teaching strategies and equitable learning environments in advanced mathematics.

Digital Grief Technology To Support Bereavement: A Systematic Review Of Potential Benefits And Risks, Xun Ci Soh, Adalia Yin Hui Goh, Paye Shin Koh, Andree Hartanto

Research Collection School of Social Sciences

Grief is a universal and inevitable experience. However, the way we support the bereaved is changing, especially in the digital era. This systematic review examines the potential benefits and risks associated with various digital grief technologies, including online grief support groups, generative AI chatbots, online memorials, online therapy interventions, virtual reality, and digitally reproduced visuals or audio of the deceased. A systematic search was conducted in seven databases, and 30 articles were included in the final review. Findings indicate that digital grief technologies offer several benefits, such as reductions in grief and depressive symptoms, enhanced social support, greater accessibility, and …

A New Approach To Generate Combinatorial Patterns In Logical Analysis Of Data And Its Application To Predict College Retention, Salihah Ahmed E. Jaafari

Theses and Dissertations

Student retention and degree completion remain central challenges for higher-education institutions, with significant implications for student success, institutional effectiveness, and public accountability. While advances in predictive analytics have enabled earlier identification of students at risk of withdrawal, many commonly used machine learning approaches suffer from limited interpretability, constraining their practical usefulness for advising, intervention, and policy decision making. This dissertation addresses the problem of predicting student persistence by developing and evaluating optimization based, interpretable classification models within the Logical Analysis of Data (LAD) framework. Building on existing LAD formulations, this research introduces two novel pattern generation models, the Best Term …

Exploration Of Extended Chemical Reaction Networks, Ramiro Santos

Theses and Dissertations

Chemical Reaction Networks (CRNs) is a well-established model for analyzing distributed and concurrent systems. A central problem studied across CRNs is the reachability problem, which asks whether a target configuration can be obtained from a given initial configuration through a sequence of valid transitions. Classical CRNs are highly expressive but not Turing-universal; their reachability problem is Ackermann-complete, indicating extremely high computational complexity that nevertheless falls short of full universality.

In this thesis, we study Extended Models of Chemical Reaction Networks in which the dynamics of the system are modified. We analyze these models through two fundamental questions. First, simulation, we …

Using Siamese Neural Networks To Effectively Detect Trojans In Fpgas When Trojans Manipulate Encryption Operations At The Bitstream Level, Kylie Arnett

Graduate Theses and Dissertations (2019 - present)

This research investigates security vulnerabilities in Field-Programmable Gate Arrays (FPGAs) at the bitstream level, focusing on hardware trojans (HTs) that manipulate encryption operations. This study addresses two critical questions: (1) The feasibility of exploiting FPGA bitstreams to selectively bypass encryption operations when a predefined input pattern is observed (all ones), thereby exposing sensitive data, and (2) the efficacy of Siamese Neural Networks (SNNs) in detecting such trojans with high accuracy. FPGAs are vulnerable to malicious modifications during manufacturing or deployment, posing risks to data integrity and system functionality. In this work, a trojan is inserted into a Xilinx series-7 FPGA …

Polyglot File Detection For Forensic Investigations, Chase Stevens

Graduate Theses and Dissertations (2019 - present)

As technology has become far more ubiquitous over the years, so too has the amount of digital evidence that can and needs to be collected and processed. Forensic tools are developed in response to the growing need, but are limited to what they are programmed to do. One such forensic tool is Autopsy, one of the most widely used open-source tools. Autopsy uses known file-type signatures (e.g., headers, trailers) to identify and recover files from forensic images. Polyglot files introduce a unique problem to both these forensic tools and investigators alike. In the context of the research conducted, polyglot files …

Detecting Sophisticated Cyberattacks On Public Water Infrastructure, Ayrton Purdy

Graduate Theses and Dissertations (2019 - present)

In recent years there has been an increasing number of cyberattacks on public water generation and distribution systems. Advanced persistent attackers could usurp sensors and control systems to contaminate public drinking water. In order to conceal their malicious activity, they can manipulate sensor data flows to give the appearance of normal activity. The compromised sensors would report normal chemical levels even though unsafe water is entering the distribution system. In response, this research proposes a multi-sensor, cross-comparison approach to anomaly detection. The proposed approach is designed to detect sophisticated cyberattacks which are not easily detectable using traditional cyber tools. The …

Developing A Framework For Microchip Design Recovery, Eric Diep

Graduate Theses and Dissertations (2019 - present)

Due to the increase in diverse chip production over the past decade, reverse engineering has become a difficult and daunting task. This research develops a methodology for microchip design recovery, seeking to validate and reproduce prior approaches to physical reverse engineering using low-cost tools and techniques. We used mechanical hardware abrasion tools and techniques to delayer and capture silicon integrated chip (IC) layout. We focused on the Mifare Classic EVl microchip, commonly implemented in public transit/transportation cards, to extract information for design recovery. The research explores limitations and advantages of mechanical abrasion and optical microscopy in context to modem chip …

Passive Microwave Remote Sensing Of Flash Drought Impacts On Vegetation, Quinton R. Deppert

School of Natural Resources: Dissertations, Theses, and Student Research

In 2002, Dr. Mark Svoboda characterized a new form of drought known as flash drought. Flash drought was defined as a rapid decline in vegetation health caused by severe heat and drought. In recent years, attempts to quantify the impacts of flash drought via precipitation, soil moisture, evapotranspiration, and temperature indicators have proliferated. What has rarely been quantified is what the rapid decline in vegetation health amid flash drought looks like through remote sensing. This is because vegetation health indices like the Normalized Difference Vegetation Index (NDVI) are derived from the visible and infrared regions of the electromagnetic spectrum and …