Evaluating Drug Concentration Profiles In Wastewater To Develop A Framework For Estimating Drug User Populations, Carl Michael E. Espinosa

All Theses

Chemical compounds, including licit and illicit drugs can be measured in wastewater and used to assess community drug consumption, providing valuable information for public health agencies, law enforcement, and local communities. While previous research primarily focused on estimating the per capita community drug consumption using back-calculation, this research focused on utilizing literature-derived parameters including drug dosage, renal excretion fraction, and sewer stability to develop a framework to estimate the user populations using Monte Carlo simulations. Samples were collected from two wastewater treatment facilities representing the Generostee Creek WWTP’s sewershed (GCS) and Mauldin Road WRRF’s sewershed (MRS). The target analytes included …

Characterization, Transport Modeling, And Image Analysis Of Rover-Terrain Interaction For Lunar Regolith In-Situ Resource Utilization, Luke A. Manolescu

All Theses

NASA has declared a return to the lunar surface and the need and demand for sophisticated In-situ Resource Utilization (ISRU) is the highest in history. ISRU will require regolith excavation, transport, and processing in order to harvest the valuable resources available, support surface operations, and keep astronauts alive. Characterizing the lunar regolith is essential to understanding the mechanical and physical behavior of the material that will be used to construct berms and structurally support astronaut habitats and landers. Any construction on Earth requires an in-depth geotechnical site assessment prior to any construction to rule out any potential site issues that …

Investigating The Effects Of Draw Parameters On The Refractive Index Profiles Of Phosphosilicate Fibers, Brandi Baldus

All Theses

P₂O₅ is a common dopant core material in silica-based glass optical fibers, in part due to its ability to increase the refractive index of silica, required for the fiber to guide light. However, P₂O₅-doped fibers can show a significant decrease in the refractive index profile compared to that of the parent preform. The question arises as to whether the refractive index decreasing could be a direct result of the fiber draw process and, if so, what is it about the draw process that causing such changes in phosphosilicate fibers. More specifically, this Thesis explores the hypothesis that these draw-induced reductions …

Electrokinetic Flow Instabilities In Non-Newtonian Fluids With Conductivity Gradients, Md Mainul Islam

All Theses

Electrokinetic instabilities (EKI) arise in electrically driven flows because the applied electric field interacts with spatial variations in electrical conductivity, generating electric body forces that can destabilize fluid interfaces. EKI can be beneficial by enhancing mixing in microchannels where diffusion is slow, but it can also be detrimental by disrupting stable sample transport, focusing, and separation. EKI has been widely studied in Newtonian fluids, and the electric Rayleigh number is known to govern the onset of this instability. However, very few studies have examined its behavior in non-Newtonian fluids, despite their prevalence in biological, chemical, and industrial applications. 

This thesis …

Evaluating The Potential For Chain Elongation To Produce Medium Chain Carboxylates From Anaerobic Conversion Of Lipids, Erin Boyer

All Theses

Medium Chain Carboxylates (MCCs), including caproate and caprylate, are valuable chemicals in various industries that can be produced biologically through an identified chain elongation pathway called reverse β-oxidation. During lipid degradation in anaerobic co-digesters at wastewater treatment plants, methane production is maximized to ensure the successful breakdown of the lipids. It remains unclear whether the anaerobic conversion of lipids possesses the potential to produce MCCs, and this study sought to evaluate the potential using anaerobic co-digester sludge from a full-scale wastewater treatment plant. Batch assays were conducted using the sludge from the plant as inoculum, as well as palmitic acid, …

Implementation Of A Practical Sharp Interface Saltwater Intrusion Model To Assess Future Sea-Level Impacts, Alexandra G. Defalco

All Theses

Rising sea levels caused by global warming exacerbate saltwater intrusion, the inland movement of seawater into coastal aquifers. These processes increase susceptibility to freshwater contamination, surface flooding, and infrastructure damage. Numerical models are utilized to assess hazards to coastal aquifers on a regional scale.

The U.S. Navy is currently developing a robust, reduced-order groundwater modeling platform, SWI6, that uses the sharp interface approach to approximate the location of the freshwater-saltwater interface to define the extent of saltwater intrusion within an aquifer. Featuring compatibility with MODFLOW 6 unstructured grid formats and the Newton-Raphson formulation for better solution stability, SWI6 improves upon …

An Integrated Model For Post-Hurricane Displacement, Shelter Demand And Shelter Allocation, Nirmal Adhikari

All Theses

This thesis develops an integrated tract-level framework for estimating post-hurricane displacement, short-term shelter demand, long-term shelter demand, and shelter allocation under hurricane wind hazards. The framework combines parametric wind-field modeling based on HURDAT2 and EBTRK hurricane data with HAZUS-based fragility and loss functions, uninhabitability relationships, demographic factors, and an insurance-sensitive recovery model. Tract-level insurance adequacy is estimated using American Community Survey data, National Association of Insurance Commissioners premium data, and the National Risk Index, using five scenario-based models; the combined home-value and hazard-risk model is adopted for final analyses. To evaluate post-disaster housing capacity, the study estimates the number of …

Extended Adaptive Oscillator Framework For Gait Phase Estimation With Adaptive Coupling And Transition Detection Across Locomotion Tasks, Nikhila Radha Krishnan

All Theses

Gait phase is a human-inspired physical variable that describes the instantaneous position of a person within a gait cycle. Adaptive oscillators have been widely used for gait phase estimation due to their ability to synchronize with periodic and pseudo-periodic biomechanical signals and generate monotonically increasing cyclic phase values. Typically, the performance of adaptive oscillators is strongly influenced by coupling strength, a parameter that bridges a trade-off between convergence speed and steady-state variability of the estimated stride frequency. In gait assistive applications, stride frequency estimation must be sufficiently fast to enable phase-based assistance while achieving a stable stride frequency estimate. The …

The Aggregation Of Microplastics By Enhancing Extracellular Polymeric Substance Production In Pseudoalteromonas Sp. Ncimb 2021 To Improve Removal Efficiencies In Environmental Matrices, Janelle L. Mercer

All Theses

Microplastics (MP) are ubiquitous in the natural environment and are a growing threat due to their small size and durability. Plastics are released into the environment through improper waste management, wastewater treatment outfalls, industrial spills, agricultural runoff, and landfills. These particles breakdown into secondary MP through degradation pathways. MP, less than 5 mm, require intricate removal techniques from water systems. Filtration techniques, though viable and effective, have implementation constraints due to high cost, maintenance demands, and filter fouling. By integrating coagulation and flocculation processes prior to filtration, MP removal efficiencies can increase, while minimizing operational challenges during filtration. Extracellular polymeric …

Evaluation Of Ostomy Pouching Change Practices Among Hospital-Based And Community-Based Nurses, Hannah Gerlach

All Theses

An estimated 725,000 to 1 million Americans are living with an ostomy and depend on ostomy pouching systems as part of their daily care. Effective ostomy management requires regular pouch changes and consistent skin care to prevent peristomal skin complications. Many individuals living with an ostomy face long-term challenges in managing their ostomy care, which can negatively affect their health-related quality of life. There is a need to understand how professional experience across different care environments, such as hospital-based and community-based settings, influences ostomy nursing care practices.

This study evaluates how nurses working in hospital-based settings and community-based settings perform …

Effects Of A Passive Assistive Hamstring Device On Overground Running Kinematics And Hamstring Activation., Quinn Castner

All Theses

Hamstring strain injuries are among the most common and recurring injuries in sports, occurring most often during the terminal swing phase of gait. Despite progress in rehabilitation, the incidence of injury has only increased, suggesting a need for a novel intervention. We designed a passive, assistive, wearable device with two specific criteria in mind: to offload the hamstrings during running, and do so without hindering normal kinematic patterns. The device consists of an adjustable elastic band anchored proximally at the waist and distally just above the ankle joint center. It stretches and shortens with the hamstrings, providing passive hip extension …

Neural-Network-Based Modeling Of Grid-Forming Inverters, Jacob D. Levesque

All Theses

Renewable energy production has grown significantly in recent years and continues to expand, resulting in an increasing number of inverter-based resources (IBRs) in the grid. As the number of IBRs in the grid continues to grow, grid-forming (GFM) inverters are becoming increasingly popular due to their ability to regulate voltage and frequency, providing increased grid stability and enabling islanding. As GFM inverters become more widely used in power systems, accurate and efficient models of their behavior are needed for system design purposes.

Emerging advances in neural networks have led to research on computationally efficient neural-network-based (NN-based) modeling approaches for inverters. …

Fluorescence-Based Quantification Of Hepatic Ldl Uptake And Donor Hepatocyte Engraftment Using Atto 700–Labeled Ldl, Victor Agustin Cortes Flores

All Theses

Familial hypercholesterolemia (FH) is an inherited disorder characterized by elevated low-density lipoprotein cholesterol (LDL-C) that increases the risk of premature atherosclerotic cardiovascular disease. In severe FH, including low-density lipoprotein receptor (LDLR), hepatic LDL clearance is profoundly impaired and many lipid lowering treatment strategies have limited effectiveness. Current advances in ex vivo CRISPR–Cas9 hepatocyte gene editing in vivo and ex vivo approaches for treatment of FH are under development.

However, a central barrier to translation is the ability to quantitatively measure the percentage of healthy gen edited hepatocytes in the liver while simultaneously assessing functional hepatic LDL handling. This thesis establishes …

Increasing The Number Of Injections Per Cycle In A Gasoline Compression Ignition Strategy: An Experimental Study, Joshua Murray

All Theses

Gasoline Compression Ignition (GCI) is an advanced compression ignition strategy which utilizes the high octane number of gasoline to improve diesel soot and NOx emissions by enabling partially premixed injections of fuel. GCI work in the literature typically uses single, double, or triple injection strategies, with higher numbers of injections noted for their ability to achieve low MPRRs, improved soot and NOx emissions, and higher efficiency. Thus, this study extends the literature by evaluating quadruple and quintuple injection strategies for continued improvement in engine efficiency and emissions.

The experiments in this work are conducted on a heavy-duty Detroit Diesel DD13 …

Exercise-Induced Muscle Damage As A Model For Exploring The Effects Of Pain On Gait, Sydney Savage

All Theses

Persistent gait asymmetry following anterior cruciate ligament reconstruction (ACLR) is a recognized contributor to post-traumatic knee osteoarthritis, yet the independent role of pain in driving altered movement patterns remains poorly understood due to confounding factors inherent to clinical populations. This study used exercise-induced muscle damage (EIMD) as a controlled experimental model to isolate the effects of musculoskeletal pain on gait, independent of kinesiophobia, structural damage, and proprioceptive disruption. Eighteen healthy adults underwent unilateral eccentric calf-raise protocols to induce delayed onset muscle soreness (DOMS), with gait assessed at baseline, 48 hours, and 168 hours post-exercise using bilateral inertial measurement units. Outcomes …

Design And Development Of A Perfusable Hydrogel Platform With Bioprinted Human-Endothelialized Microvascular Channels, Calvin A. Chernyatinskiy

All Theses

We developed an integrated bioprinting and perfusion platform to generate vascularized hydrogel constructs that support perfusable microchannel networks. Multiple hydrogel formulations, sacrificial ink systems, device geometries, and perfusion conditions were systematically evaluated to optimize print fidelity, mechanical stability, and cellular compatibility. Internally gelling alginate–calcium carbonate hydrogels were identified as a robust matrix, providing tunable gelation kinetics and structural stability during embedded printing. In parallel, Pluronic F-127 fugitive ink enabled reliable fabrication of continuous hollow channels due to its shear-thinning behavior and efficient post-print removal.

The finalized platform integrates stereolithographically fabricated perfusion chambers with extrusion-based bioprinting to produce three-dimensional, perfusable vascular …

Exploration Of Real-Time Power Electronic Simulation On Amd Npu, Shouyu Du

All Theses

The rapid electrification of the automotive and data center sectors has created a critical demand for high-fidelity, real-time simulation of complex power electronic systems. While Hardware- in-the-Loop (HIL) simulation on Field-Programmable Gate Arrays (FPGAs) is the current industry standard, it presents significant challenges regarding development complexity and memory limita- tions. This dissertation investigates the feasibility of utilizing Neural Processing Units (NPUs)— specifically the AMD AI Engine (AIE) XDNA2 architecture—as a novel platform for real-time, deterministic circuit simulation. This study establishes a comprehensive automated modeling framework based on graph theory and Massarini’s method to derive linear state-space representations for arbitrary circuit …

Implementation Of A Local Llm Serving System For Agentic Ai, Zhiheng Ni

All Theses

This thesis presents a system that allows large AI models to run directly on personal devices instead of relying on cloud servers. Recent advances in artificial intelligence, especially large language models (LLMs), have made it possible to build powerful applications such as chatbots, coding assistants, and intelligent agents. However, most of these systems run in the cloud, which raises concerns about privacy, latency, and cost.

To address these issues, this work develops a local AI serving system that runs efficiently on a specialized hardware component called a Neural Processing Unit (NPU). The system provides a unified interface that supports multiple …

Investigation Into The Effects Of Moderate-Dose Radiation On Ligament Biomechanics, Andrew Landefeld

All Theses

Recent advances in arthritis treatment pin ionizing X-ray radiation as a useful tool in reducing joint pain and immune response. However, due to a lack of fundamental research in the effects of low-dose ionizing radiation on tendon and ligament biomechanics, the safety of these studies is rather unknown. While most related studies investigated cellular response to low dose treatment, surrounding tissue physiology is left out of the picture. Additionally, moderate range doses of irradiation are rarely studied, as most uses of radiation on tendons and ligaments are for sterilization of cadaver tendons for allografts. This study provides a preliminary investigation …

Feasibility Study Of Transitioning From Thick Plates (0.250”) Mounted On 30-Point Pvc Carriers To Thinner Plate Technologies Mounted On Recyclable Foam And Pet (0.155”) For Post-Print Corrugated, Nathaniel J. Poole

All Theses

In the United States, the most common press configuration for brown-box printing is a 0.280” undercut press. These press configurations have long relied on thick 0.250” plates mounted on 0.030” PVC sheets to print onto corrugated substrates. Each year, around twenty million pounds of waste are produced by the printing industry, through paper waste, plate waste, among other materials. One large factor of that waste is flexographic plate waste, which either ends its life in a landfill or is repurposed into other products. This study establishes a comparison between traditionally used 0.250” plates on 30pt PVC versus 0.155” plates mounted …

Robust Hardware Trojan Detection Leveraging Dual‑Domain Features And Stacked Ensemble Learning, Sefatun-Noor Puspa

All Theses

In Cyber-physical systems rely on sensors, communication, and computing, all powered by integrated circuits (ICs). These ICs are vulnerable to malicious hardware attacks, with hardware Trojans being one of the stealthiest threats. Trojans are malicious implants in the circuitry, which are often inserted during design or fabrication stages. This stealthy addition remains dormant until triggered and might cause functional disruptions or sensitive information leakage once triggered. Traditional IC validation methods, such as functional testing and logic analysis, usually fail to capture these subtle anomalies because hardware Trojans are intentionally designed to mimic normal circuit behavior. They often remain dormant under …

Laser-Induced Acoustic Signal Generation, Resonance Characterization, And Optical Sensing In Metallic Plates, Xinghang Zhao

All Theses

This thesis investigates laser-induced acoustic signal generation, resonance characterization, and optical sensing in metallic plates as a foundational study for damage-sensitive inspection. Rather than presenting a complete defect-detection system, the work focuses on how measurable acoustic responses can be generated, amplified, and interpreted in a controlled laboratory setting. Experiments showed that pulsed-laser excitation can produce strong and repeatable acoustic responses in metallic structures. Repetition-rate sweeping identified narrow resonant responses, including a cantilever resonance at 57.862 kHz and a maximum circular-disk response at an FFT frequency of 48.8 kHz with a laser repetition rate of about 49.1 kHz. High-Q resonances exceeding …

Enhanced Situational Awareness Of Solar Pv Plants For Near Real-Time Planning And Operation In Modern Power Systems, Michael A. Walters

All Theses

Solar photovoltaic (PV) plant development and utilization is increasing worldwide but remains intrinsically challenged by its large dependence on highly variable weather conditions and operating states. This paper presents a framework to leverage three new situational awareness indices (SAIs), namely: weather condition index (WCI) to gauge operational performance based on environmental states, operational complexity index (OCI) to indicate the severity of power generation reductions, and photovoltaic generation index (PVGI) to provide a final determination of the impact on power generation and to bolster situational awareness in planning and operational contexts for solar PV plants. This is accomplished by exploiting the …

Field Testing Of Retrofits To Improve The Structural Behavior Of South Carolina Flat-Slab Bridges, Jacob Bowers

All Theses

The South Carolina Department of Transportation manages approximately 2,300 “flat-slab” bridges statewide, with an average age of 58 years, according to the National Bridge Inventory (NBI 2024). Many of these structures were originally designed for H10 or H15 truck loadings, which are significantly below current design standards. As a result, numerous bridges have been load-posted, restricting freight movement, emergency response, and local connectivity. While full replacement provides a long-term solution, it is often cost-prohibitive and disruptive. Accordingly, the South Carolina Department of Transportation is seeking cost-effective retrofit strategies that improve performance and extend the service life of these bridges. Implementing …

Estimation Of The Mechanical Properties Of South Carolina Timber Piles Using Non-Destructive Evaluation Methods And Experimentally-Informed Models, Aashish Sapkota

All Theses

South Carolina has about 2,600 bridges that are supported by nearly 75,000 timber piles. They are increasingly vulnerable to biological decay, cracking and impact damages after decades of service. Current inspection methods used by the South Carolina Department of Transportation (SCDOT), such as hammer sounding and awl probing, are labor-intensive and expensive. This study investigated non-destructive evaluation (NDE) methods, including micro-resistance drilling and stress wave timing, as alternatives for assessing timber pile condition.

Ten timber piles were collected from two South Carolina bridges, and their above-grade portions were cut into 40 specimens approximately 13 to 15 inches long. Specimens were …

Robustness Of Vision Language Models For Pedestrian Detection Tasks, Ostonya K. Thomas

All Theses

Autonomous vehicle (AV) systems typically employ modular systems in which discrete components handle separate tasks such as perception, computation, and path planning. While flexible, this approach allows errors to propagate and compound across the pipeline, and many AI systems offer little transparency into their internal decision-making. Such limitations are particularly concerning in safety-critical domains where failures can carry lethal consequences. Vision Language Models (VLMs) have emerged as a promising alternative because they support end-to-end implementations that bypass compounding error risks and provide natural language explanations of their outputs. Despite these advantages, prior research has demonstrated that both computer vision systems …

Multimodal Aerial Image-Based Ground Object Detection And Classification Using Yolo, Erik Nielsen

All Theses

Object detection in unmanned aerial vehicles (UAVs) present a unique challenge due to small object sizes, varying viewpoints, and changing environmental conditions. These challenges are exacerbated when operating during daytime and nighttime scenarios where illumination differences can heavily impact detection performance. This work is motivated by military object detection applications where the ability to reliably identify small objects such as landmines or unexploded ordnance from aerial imagery presents a critical safety need and a significant technical challenge. In this paper, we investigate object detection using both visible (RGB) and infrared (IR) imagery to improve robustness and reliability across diverse operating …

The Impact Of Dipeptides On Product Quality In Chinese Hamster Ovary Cells, Louise C. Herman

All Theses

Biopharmaceuticals are medicines produced in cells which are used to treat diseases such as cancer. Monoclonal antibodies (mAbs) represent the majority of approved biotherapeutics. MAbs are mostly produce using Chinese hamster ovary (CHO) cells. CHO cells are favored for resiliency, scalability, and established safety, and are considered the “workhorse” organism for biopharmaceuticals.  Amino acids are a key component of cell culture media, however several amino acids have solubility limits, such as cysteine, cystine, and tyrosine.  At neutral pH, these amino acids are poorly soluble.  However, dipeptides, such as N,N'-di-L-Alanyl-L-Cystine (ACCA) have been reported to increase cysteine and cystine availability. Further, …

Bayesian Assembly Tool For Intelligent Digital Twin Selection, Shishir Sharma

All Theses

Digital twins can be used for system performance optimization, health monitoring, predictive maintenance, and investigating system anomalies. A ground vehicle digital twin may be assembled using representations of the subsystem models (tires, suspension system, powertrain, etc.) of different fidelity. Lower fidelity Digital Twins have relatively simpler design and physics, hence are generally computationally less expensive, but may not represent the physical system accurately. On the contrary, higher fidelity Digital Twins are generally more precise in their ability to represent the physical system, but due to complexity, are usually computationally more demanding. This thesis describes the application of Bayesian Classification within …

Development Of Low-Cost Triaxial Force Sensor For Measurement Of Human-Exoskeleton Interaction Forces, Hamdan Khan Sarvathullah

All Theses

Contemporary research suggests that shear force is a major contributor to discomfort and pressure injury. However, the variation of shear forces during human-exoskeleton interaction dynamics is a highly unexplored field. The high cost of commercial triaxial force sensors may be a major factor in the notable lack of research in this field. Therefore, in this paper, we present a low-cost, 3D-printed triaxial force sensor designed specifically to measure the triaxial interaction forces between an exoskeleton and its user. The triaxial force sensor uses Carbon-Black/Silicone Rubber (CB/SR) strings to measure shear forces, whereas the normal force is measured with a Force …