Digital Commons Network^™

Age And Characteristics Of Quaternary Fluvial And Dune Deposits Along The Arkansas And Cimarron Rivers In Osage And Pawnee Counties, Oklahoma, Barry A. Duncan

Graduate Theses and Dissertations

Quaternary aeolian and fluvial deposits along the Arkansas and Cimarron Rivers in Osage and Pawnee counties of central Oklahoma, record Late Pleistocene and Holocene fluvial landscape history in the eastern Osage Plains. Sediment supply, climate variability, channel incision, and channel migration control this landscape evolution. Sediment supply of both streams is dominantly sand. Late Pleistocene and Holocene precipitation have varied with periods of drought alternating with increased precipitation and warming. The study area is near the eastern boundary of substantial aeolian activity with drought and aeolian reworking of fluvial sand more severe to the west. This study examines the sediment, …

Nanoscale Electrochemical Measurements: Theory, Instrumentation, And Operation, Kamsy Lerae Anderson

Graduate Theses and Dissertations

Electrochemical processes underpin many modern technologies (e.g., batteries, fuel cells, and corrosion protection systems), and because these processes are often controlled by interactions that occur at the nanoscale, gaining insight into nanoscale electrochemical behavior is essential to advancing these technologies. Nanoscale electrochemical imaging probes measure electrochemical activity with nanoscale spatial resolution and have enabled researchers to gain new insights into diverse experimental systems. However, limitations remain, including a lack of methods for direct quantitative interpretation, the influence of atmospheric conditions on experimental reproducibility and stability, and a knowledge barrier resulting from limited accessible resources, all of which continue to restrict …

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 …

Of Dunes And Ice: A Surface-Atmosphere Investigation Of Mars Co2 Sublimation Features And Titan Aeolian Fields, Racine D. Cleveland

Graduate Theses and Dissertations

This dissertation investigates a central question: How do planetary boundary layer processes manifest in observable surface geomorphology, and how can planetary imagery be used to quantify those effects? The planetary boundary layer (PBL) governs near-surface exchanges of momentum, heat, and volatiles, yet direct atmospheric measurements remain spatially and temporally limited on most planetary bodies. By analyzing geomorphic features preserved in high-resolution imagery, this work quantifies how boundary-layer processes leave measurable signatures on planetary surfaces. For Mars, high-resolution images from the Mars Reconnaissance Orbiter (MRO) HiRISE instrument were used to map CO2 sublimation features, or Swiss Cheese Features (SCFs), on the …

Advancing Apparel Education Through 3d Simulation In Vstitcher: Confidence, Competence, And Career Readiness In Higher Education, Jonah Diniakos Graham

Graduate Theses and Dissertations

The rapid adoption of 3D garment simulation in the apparel industry has created new demands of higher education to better prepare students with both technical proficiency and confidence within digital design platforms to better enable them for many career avenues. This study examines the integration of Browzwear’s VStitcher in an undergraduate apparel production course, addressing the need to assess both competence and self-confidence in digital garment construction while also fostering broader career readiness competencies. Guided by a combination of Self-Determination Theory (SDT) and Situated Expectancy-Value Theory (SEVT), the study emphasizes the role of autonomy, competence, and relatedness in the shaping …

Impacts Of Climate-Smart Agriculture On Greenhouse Gas Emissions In Southeast Arkansas Cotton, Cassandra Seuferling

Graduate Theses and Dissertations

Increasing concerns of climate change have led to the evaluation of greenhouse gas (GHG) emissions [i.e., carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O)] from agroecosystems, particularly cotton (Gossypium hirsutum) production. Technology improvement and conservation agriculture methods [i.e., reduced-tillage (RT) instead of conventional tillage (CT) and the use of cover crops (CC)] require further evaluation regarding GHG emissions from Arkansas cotton production. The first objective of the study was to evaluate four gas-flux-determination methods [i.e., linear or exponential regression models, with negative fluxes (WNF) included in the dataset or replacing negative fluxes (RNF)] on CO2, CH4, and N2O fluxes …

Advancement In Electrochemical Generation-Collection: Snapshot Redox Cycling Voltammetry For Rapid Analysis At Chip-Based, Individually Addressable Microband Electrode Arrays, Blake Aleck Sterling

Graduate Theses and Dissertations

Snapshot redox cycling voltammetry (Snapshot RCV) is introduced as a rapid electrochemical technique that reconstructs the current-potential profile of a redox active species using a microband electrode array. By simultaneously biasing individual generator electrodes alternating in the array to different voltages across the analyte’s potential range while individually holding collector electrodes at a reversing potential, “spatial” voltammetry is achieved in as little as 1 s with the temporal speed of chronoamperometry, rapidly capturing the steady-state redox cycling (RC) profiles. During RC (a mode of generation-collection), the analyte is oxidized (or reduced) at generator electrodes and converted back at neighboring collector …

Explainability In Deep Learning For Density Regression, Dalton James Oxford

Graduate Theses and Dissertations

Classical statistical methods focus on explainability and inferential power. Machine learning and deep learning can handle non-linear, high-dimensional data better than traditional methods. In modeling, a clear understanding and interpretation are essential to decision-making. Recent work in quantile regression and extreme modeling has begun to use deep learning due to its performance on high-dimensional, non-linear data. Semi-Parametric Quantile Regression (SPQR) is a nonparametric spline-based approach to quantile regression that estimates the conditional PDF and CDF of the response. Semi-Parametric Quantile Regression for Extremes (SPQRx) is a recent extension of SPQR that provides two features: out-of-sample estimation and accurate extreme-tailed estimation. …

Quantifying The Short-Term Hydrogeologic Responses Of Highway Construction In Hot Springs, Arkansas, Billy Jack Summerford

Graduate Theses and Dissertations

In late 2020, excavation for the Highway 5 Bypass in Hot Springs, Arkansas exposed seepage faces along roadcut walls. Groundwater levels at nearby wells decreased by up to 20.9 ft and have remained ~20 ft below pre-construction values on average. This study quantifies changes in storage in the unconfined aquifer within the Hot Springs thermal recharge zone associated with the seepage faces using a numerical groundwater model calibrated to pre-construction head at well ARb4. Model scenarios are used to evaluate whether construction-induced seepage or drought best explains the decrease from late 2020 to early 2021. The numerical groundwater simulation represented …

Strain Engineering Of Excitonic And Vibrational Properties In Two-Dimensional Transition Metal Dichalcogenides, Sneha Minesh Patel

Graduate Theses and Dissertations

Mechanical strain represents a robust and non-invasive method for tuning the electronic and vibrational properties of two-dimensional transition-metal dichalcogenides (TMDs). This work examines homogeneous biaxial strain as a symmetry-preserving control parameter that governs excitonic and interlayer dynamics in atomically thin TMDs. In monolayer MoSe2, biaxial tensile strain is intrinsically generated during high-temperature physical vapor deposition due to thermal expansion mismatch with amorphous substrates. Optical spectroscopy demonstrates substantial and tunable excitonic energy shifts exceeding 100 meV per percent strain. Polarization-resolved second harmonic generation confirms the retention of lattice symmetry under biaxial deformation. The investigation is further extended to bilayer MoS2, where …

Privacy Protection In Machine Learning: Methods For Structured And Unstructured Data, Karuna Bhaila

Graduate Theses and Dissertations

As machine learning models become increasingly integrated into data-driven decision-making, the protection of sensitive information throughout the model lifecycle is a paramount concern. As these models process and memorize sensitive, proprietary, or personal data, they risk leaking information through their outputs or internal states, especially in domains such as healthcare and finance. The protection of data in machine learning has thus been a crucial field of study. Within this paradigm, researchers have studied theoretical and application-oriented mechanisms for realizing privacy protections for various data formats. Nonetheless, privacy in machine learning still has many open problems, especially with the emergence of …

Deciphering Chemomechanical Couplings In Proteins Using Molecular Dynamics And Enhanced Sampling Techniques, Matthew Brownd

Graduate Theses and Dissertations

Proteins function through a complex interplay between chemical interactions and mechanical motions across multiple spatial and temporal scales. Understanding how ligand binding, conformational dynamics, and structural flexibility collectively regulate protein function remains one of the central challenges in molecular biophysics. This dissertation presents a computational investigation into chemomechanical coupling in three distinct classes of biomolecular systems using all-atom molecular dynamics (MD) simulations and enhanced sampling methods, with particular emphasis on free-energy calculations and long-timescale conformational analysis. The first part of this work focuses on ligand binding in hyperpolarization-activated cyclic nucleotide-gated (HCN) channels, which regulate rhythmic electrical activity in the heart …

Groundwater Responses To Tidal Restoration At Pelican Marsh And Sea-Level Rise In Elkhorn Slough, California, Julie E. Nelson

Graduate Theses and Dissertations

Coastal wetlands represent a dynamic but vulnerable terrestrial-aquatic interface with future resilience controlled by historic hydrologic alterations, sea-level rise, and groundwater extraction. In diked coastal settings, poor tidal connectivity can degrade habitat from the impoundment of freshwater or hypersaline surface waters. Restoring tidal connectivity could foster marsh revitalization, but altering the surface hydrologic system could lead to unwanted salinity intrusion in shallow aquifers. Saline groundwater intrusion degrades freshwater quality and, while inevitable with sea-level rise, could be accelerated with tidal marsh restoration. To investigate this, I developed a steady-state groundwater flow model of Pelican Marsh, a diked, muted tidal marsh …

Sedimentary Provenance Of The Pliocene – Pleistocene Giant Foresets Formation, Offshore Taranaki Basin, Aotearoa New Zealand, Anurag Kulkarrni

Graduate Theses and Dissertations

Sediment input and dispersal in the Taranaki Basin, offshore New Zealand’s North Island, was influenced by a complex interplay of ocean currents and sea level fluctuations over the late Neogene. This period of time was recorded in the Pliocene-Pleistocene Giant Foresets Formation (GFF) that represents a rapid progradation of the western continental shelf into the basin. High sedimentation rates during this time were likely a major contributing factor to the emplacement of multiple, large-scale (up to ~3,500 km3) mass-transport deposits (MTD) that were caused by shelf and slope collapse within the GFF of similar scale to that of the well-studied …

Developmental Mathematics As A Potential Barrier To Degree Completion In Community Colleges, Cynthia Bernice Fletcher

Graduate Theses and Dissertations

Developmental mathematics is often seen as a barrier to student progression in community colleges, especially for students pursuing Associate of Science degrees requiring math coursework. This quantitative, ex post facto, non-experimental study examined how developmental mathematics factors predicted Associate of Science degree completion at a two-year community college in the West South-Central United States. Specifically, it assessed how academic performance in developmental mathematics, placement method, math pathway, and number of developmental math courses related to Associate of Science degree completion, as well as differences across student subgroups. Archival institutional data were used for first-time-in-college students across four cohorts: 2018, 2019, …

Genre Prediction Using Rnns And Llm-Enhanced Video Game Review Data, Gabriel Young

Graduate Theses and Dissertations

LLMs (Large Language Models) are powerful tools for engaging with textual data, carrying many advantages over classical NLP (Natural Language Processing) and ML (Machine Learning) approaches. However, a classical ML model can still be faster, more efficient to run, and accessible than an LLM. We seek to gain the benefits of LLM text comprehension and preserve them in a classical ML model, a hybrid approach. The LLM operates on text to surface relevant information and associations in our problem space, then the ML model trains on the LLM output. The model may learn from the LLM and provide a more …

Sel & Hil Integrations For Real-Time Cyber Threat Modeling, Risk Assessment, And Result Validation, Zachary Coel Harris

Graduate Theses and Dissertations

The electrical power grid is one of the most critical infrastructure systems, with virtually every other critical system relying on its electricity to operate effectively [1]. One failure in the electrical grid can have cascading effects, reducing, or outright stopping the operation of services vital to people’s lives. Ensuring continuous availability of the electrical grid is vital. This constant need for availability poses a challenge to identify potential cyber-attacks and their impacts. The grid is constantly growing with the addition of DERs (Distributed Energy Resources). Common DERs, such as photovoltaic systems or wind farms, can provide primary or secondary generation …

From Data Digitization To Personalized Care: Deep Learning And Decision Analytics In Healthcare Systems, Ahla Ko

Graduate Theses and Dissertations

This dissertation traces a progression from foundational data infrastructure to individualized clinical decision-making, developing and evaluating three computational frameworks that advance healthcare efficiency and personalization through deep learning and decision analytics. The first study presents an end-to-end pipeline for automated recognition of handwritten medical forms, addressing persistent challenges in health data digitization. Integrating a YOLO-based field detection model, a Convolutional Recurrent Neural Network (CRNN) for text transcription, and a confidence-based human-in-the-loop quality assurance framework, the system achieved 99.75\% Exact Match Accuracy and a 0.13\% Character Error Rate on medical forms collected from a tuberculosis research project in Moldova. A GPU-accelerated …

Solid Embedded Telemetry, Pranav Balasubramanian Natarajan

Graduate Theses and Dissertations

This thesis explores the integration of the Solid decentralized data framework within embedded and legacy energy control systems to enable secure, access-controlled, and interoperable data exchange. Two implementations were developed to evaluate Solid’s practical applicability: an ESP32 client implementing Solid-OIDC authentication and telemetry publication to a Solid Pod, and a Modbus-to-Solid bridge translating Modbus RTU communications into RDF-based data for bidirectional control. Experimental evaluation highlighted the effects of task scheduling and blocking operations on the ESP32, and polling-based communication latency within the Modbus bridge. These findings reveal the architectural and computational trade-offs involved in extending Solid to constrained or protocol-bound …

Effects Of Wetting And Drying On Nutrient Mobilization In Aquatic Systems, Karessa Grace De La Paz

Graduate Theses and Dissertations

Wetting and drying cycles are a fundamental, but underexplored, control on nutrient mobilization and transport in aquatic ecosystems. Such intermittency impacts approximately 60% of the world's streams and rivers, and the extent is expected to increase with future climate change. Additionally, aging reservoir infrastructure is driving restoration efforts, like large-scale drawdowns, that can expose benthic sediments to extended dry periods before refilling. Despite the prevalence of wet-dry cycles, how they influence nutrient transport and mobilization across different aquatic ecosystems remains poorly understood. To address this gap, this thesis presents two complementary studies exploring nutrient dynamics in Arkansas aquatic ecosystems that …

Turbulent Plenum Jet-Crossflow Validation Via Subgrid Scale Model Variation And Upstream Forcing Under Dynamic Hybrid Rans-Les, Cole W. Mccallum

Mechanical Engineering Undergraduate Honors Theses

In modern gas turbine design, film cooling has become ubiquitous as a method for limiting heat transfer between high temperature gases post-combustion and the surface of downstream blades. This paper validates the use of various computational fluid dynamics techniques in recreating an experiment measuring adiabatic effectiveness over a surface downstream of a compound-angle N2 plenum jet incident on a turbulent-air boundary layer [1]. To do this, both RANS and Dynamic Hybrid RANS-LES (DHRL) methods are implemented and compared to previous research [2]. The latter method is then modified through implementation of a different subgrid scale (SGS) model and through addition …

Draft Final Annual Operations And Maintenance (O&M) Report: Butte Treatment Lagoon (Btl) System – 2025, Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Draft Final 2026 Interim Site-Wide Groundwater Monitoring Quality Assurance Project Plan, Woodard & Curran

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Draft Final 2024 Reclamation Improvement Sampling: Bres No. 78 – Original Mine Yard Site Evaluation Summary Report, Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Degradation And Metabolic Analysis Of Synthesized Quorum-Sensing Signals By The Model Eukaryote Chlamydomonas Reinhardtii, Adam Josef Bach

Theses and Dissertations

Bacterial organisms can “talk” with one another on a colony-wide scale using a communication system known as quorum-sensing (QS) via chemical signals. These signals are produced at a basal rate throughout the life of the bacteria and are classified as autoinducers, which diffuse across the cell membrane. Once the critical concentration is reached, they begin to diffuse back into the cell and initiate a phenotypic change. As these signals exist outside the membrane of their producer, they are also accessible to other organisms. It has already been noted that some plant species uptake these compounds through their roots and break …

Aircraft Fault Detection Via Weight And Bias Analysis Of A Custom First Neural Network Layer, George Harrison Chen

Theses and Dissertations

Fault detection in aircraft is traditionally handled through redundant hardware and comparison algorithms to detect failures. Alternatives like model-based residual generation and data-driven approaches such as supervised fault classification and unsupervised anomaly detection have been explored, but they suffer from practical limitations; model-based methods require accurate system models, and data-driven methods have large constraints on the data limiting scalability and adaptability. This work presents a purely data-driven neural network architecture featuring a custom first layer designed for real-time fault detection where the weights and biases of this layer are used to detect faults. The network requires zero supervision and complements …

Manned Exploration Of Satellites Of The Outer Planets: An Analysis Of Current Technologies And A Discussion Of Advancements Required, Joshua Carson Meador

Theses and Dissertations

The Solar System’s outer planets have many satellites, some of which are known to be the most likely places to find extraterrestrial life in our celestial backyard. Multiple scientific missions have been sent to glean information from these satellites, yet the possibility of a manned expedition has long been exclusive to science fiction stories. This paper intends to collect and analyze the current state of space travel technology to explore the feasibility of such a mission with modern technology and to discuss which future advancements should be the focal point for making such missions a reality. To begin, data on …

Quantifying Noise In Monte Carlo Simulations Of Cosmic Rays In A Shock, Abhro Rahman

Theses and Dissertations

Cosmic rays are a phenomenon known to humankind from the early 1900s, and yet today the details of their physical behavior are not fully settled. While the observed spectral fluxes of cosmic rays follow a power-law trend when plotted against particle energy, the exact mechanisms under which they get to such high energies are still under study. This thesis will undertake a subsection of that task, where the Monte Carlo simulation of particle accelerations is described in Warren (2015), and we aim to identify and quantify the noise inherent in such simulations. This document takes a long path through particle …

Moodify: A Mood-Based Music Recommendation System, Meghana Kagitha

Theses and Dissertations

Music has long been recognised as a powerful tool for emotional regulation, yet existing music streaming platforms often fail to align song recommendations with a user's current emotional state. Moodify is a mood-based music recommendation system designed to bridge this gap by delivering personalised playlists that reflect how a user feels in real time.

This project presents the design, development, and evaluation of Moodify, a mobile application that leverages the Circumplex Model of Emotion to capture user mood through an intuitive two-dimensional valence-arousal interface. Rather than relying on text input or manual search, users plot their emotional state directly onto …

Adaptive Artificial Potential Field Guidance And Control For Autonomous Docking With Uncooperative And Unknown Spacecraft, Steven Holmberg

Theses and Dissertations

The increasing demand for on-orbit servicing (OOS), active debris removal (ADR), and space domain awareness (SDA) missions has increased the need for autonomous spacecraft rendezvous and proximity operations (RPO) with uncooperative and unknown targets. Traditional guidance and control methods are typically designed for cooperative systems with known geometry and state information. This work builds on previous research to develop and evaluate an artificial potential field (APF)-based control framework capable of autonomous operation with minimal prior target knowledge and applicability to both relatively static and tumbling spacecraft.

The proposed APF formulation incorporates established safety constructs from cooperative docking systems, including an …