Engineering Commons^™

Shooting For The Stars: Stem Outreach Strategies Between 2nd And 7th Grade, Paige Miller

Chemical Engineering Undergraduate Honors Theses

Engineering and planetary science outreach programs are increasingly important as industries and research organizations face growing demand for STEM professionals. Despite the importance of these fields, many students receive little exposure to engineering careers during their early educational experiences. This honors thesis examines the effectiveness of interactive STEM outreach presentations designed for elementary and middle school students. Specifically, this study evaluates outreach activities centered on chemical engineering applications and the NASA M2M CO₂ regeneration project for Martian environments.

Two student age groups participated in this study: 2nd grade students at Butterfield Elementary School and 7th grade students at Woodland Junior …

A Baseline Study Of Artificial Intelligence Use Among Chemical Engineering Undergraduates At The University Of Arkansas, Natalie J. Erickson

Chemical Engineering Undergraduate Honors Theses

In recent years, artificial intelligence (AI) has shifted from a novel innovation to a tool used in daily life, particularly within higher education. While anecdotal evidence suggests high levels of student engagement with AI, empirical data regarding usage patterns remains limited. This baseline study investigates AI integration among undergraduate chemical engineering students at the University of Arkansas. Through an anonymous survey (N=68; comprising 20 freshmen, 14 sophomores, 16 juniors, and 18 seniors), researchers assessed usage frequency, student comfort levels, and their evolving relationship with AI tools. The findings reveal that 75% of respondents utilize AI for coursework at least once …

Optimizing College Food Pantry Locker Systems Through Simulation Techniques, Jacob W. Holmes

Industrial Engineering Undergraduate Honors Theses

Food insecurity affects 10.5% of households in the United States. Among those affected, college students are a group with increasing food insecurity. Through novel food pantry order methods, such as locker order systems, some effects of college food insecurity can be alleviated. The Jane B. Gearhart Full Circle Food Pantry (FCFP) at the University of Arkansas implemented a locker system, beginning in the Fall of 2020. There is a lack of investigation into locker management policies for pantries, such as how much time clients should be allowed to pick up orders after they are placed in lockers, how many lockers …

Domain-Specific Design On Fpga And Npu For Scientific Computing And On-Device Llm Inference, Miaoxiang Yu

All Dissertations

High-performance computing (HPC) is changing rapidly as scientific simulations and large language model (LLM) workloads push the need for higher performance under tight power and memory constraints. Conventional platforms such as CPUs and GPUs accelerate computation through instruction-driven parallelism, relying on multithreading, SIMD, and SIMT execution, but increasingly encounter scalability limits imposed by the power and memory walls. In contrast, Field-Programmable Gate Arrays (FPGAs) and Neural Processing Units (NPUs) offer a high-efficiency alternative through dataflow-oriented architectures that exploit deep pipelining and customized memory hierarchies to reduce data movement. However, the performance potential of these spatial accelerators remains largely unrealized when …

Physical And Optical Properties Of The Germanium-Arsenic-Selenium Glass Forming Region For Precision Glass Molding And Infrared Optics, Peter F. Wachtel Ii

All Dissertations

The growth and advancement of infrared optical systems for thermal imaging, multi-band imaging, hyperspectral imaging, medical diagnostics, and chemical sensing are pushing the material science community to better understand existing materials while also developing new materials. Additionally, the thermal imaging market continues to grow, and system designers are continually being asked to reduce size, weight, and power while reducing costs (SWaP-c). Market growth has shifted optics manufacturing towards higher volume processes such as precision glass molding, but this does require most materials to be recharacterized due to property changes resulting from the process. Affecting the SWaP-c requirements, manufacturing tolerances are …

Erratum For "Soil Freezing Characteristic Surface For Partially Frozen Soils", Antai Dong, Xiong Zhang, Ming Xiao

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The following corrections should be made to "Soil Freezing Characteristic Surface for Partially Frozen Soils" by Antai Dong, Xiong Zhang, and Ming Xiao, https://doi.org/10.1061/JGGEFK.GTENG -13924: In the third sentence of the Abstract, the value for suction when completely dried is incorrect. It should be 106 kPa. The label at the end of the suction axes in Figs. 1(a) and 2 is similarly inaccurate. Corrected versions of Figs. 1 and 2 are provided herein. To preserve the published version of record, these details have been corrected only in this erratum. (Figure Presented)

Adsorption Of Pfas On Bridged Functionalized Organosilica Materials, Elisha Lawerh Kabutey

Electronic Theses and Dissertations

PFAS are hazardous contaminants that have a devastating impact on human health and the environment. Their hazardous nature has led to the development of various adsorption methods for removing these contaminants from water sources. In this study, functionalized organosilica materials were synthesized from bis[3-(trimethoxysilyl)propyl] amine using the sol-gel method. The surface amino groups of the organosilica were converted into amine hydrochloride groups. Their adsorption properties were evaluated using salts of perfluorooctanoic acid, perfluorooctanesulfonic acid, and perfluorobutanesulfonic acid. Results showed excellent adsorption capacity of the materials. Adsorption of PFAS leads to particle agglomeration and flotation of the spent material. A column …

Design And Reliability Analysis Of A Radiation-Tolerant On-Board Computer System For Martian Surface Missions, Jack Ryan

Master's Theses

Space environments present complex challenges for electronic devices, perhaps most notably in the form of radiation effects; the natural protections provided by Earth’s atmosphere and magnetosphere are largely absent in deep space and extraterrestrial environments, making single-event effects (SEE) a critical concern. Although radiation-hardened components offer near-immunity to SEE, they possess tremendous drawbacks in both cost and performance. To circumvent such issues, this thesis investigates the feasibility of leveraging a commercial-off-the-shelf (COTS) device, the AMD KRIA K24 system-on-module (SOM), for use in Martian surface missions.

Detailed models were used to predict SEE rates in the system, and system-level fault tree …

Enhancing Control Charting Schemes And Exploring New Assessment Metrics To Advance Quality Control And Cyber-Attack Detection In Manufacturing, Ahmad Al Majali

Dissertations

The increasing integration of digital technologies and industrial control systems in modern manufacturing has introduced new cybersecurity vulnerabilities within cyber–physical production environments. Malicious actors can exploit these vulnerabilities to induce subtle process deviations that degrade product quality while remaining undetected by conventional statistical monitoring tools. Such attacks can be deliberately engineered to manipulate process behavior through transient shifts that vary in magnitude, duration, and frequency. Despite extensive research on transient shifts caused by assignable causes in Statistical Process Control (SPC), limited attention has been given to intelligently designed cyber–physical attacks that exploit the structural characteristics and limitations of control charting …

Behavior Of A Mildly Skewed Network Tied-Arch Bridge During Construction And Early Service Life, Harsha Amunugama

Dissertations

This dissertation work investigated the structural performance of the 2nd Avenue Bridge in Detroit, Michigan, the first skewed, unbraced network tied-arch bridge in the U.S. The 245-ft long, 96.5-ft wide bridge features an 18-degree skew. The bridge was constructed using accelerated bridge construction (ABC) techniques, including off-site fabrication at a bridge staging area (BSA) and installation via self-propelled modular transporters (SPMTs) and lateral launching, enabling the completion of construction with minimal disruptions to I-94 traffic and improved safety.

Given the unique structural configuration of the bridge, the use of innovative construction techniques, and differences observed in structural responses predicted by …

Calibration Refinement Of Aashto Paveme For Kentucky Asphalt Overlays, Clayton S. Cook, Kean H. Ashurst Jr., Clark Graves

Kentucky Transportation Center Research Report

The Kentucky Transportation Cabinet (KYTC) uses AASHTOWare’s Pavement ME Design Version 3.0 (PaveME) to develop mechanistic-empirical designs for new and reconstructed pavements. Transfer functions used for estimating pavement distress in PaveME rely on national calibration values derived from the Long-Term Pavement Performance (LTPP) database. However, these often fail to reflect Kentucky’s local conditions, materials, and practices. To address this issue, Kentucky Transportation Center (KTC) researchers completed local calibrations for several key transfer functions (rutting, reflective fatigue cracking, and roughness (IRI)) to improve the predictive accuracy of and reduce bias in pavement performance models developed for rehabilitation projects that involve placing …

In-Operando Imaging For Mechanistic Insights And Process Optimization In The Biofuel-Driven Combustion Synthesis Of Cement And Precursor Phases, Shubham Agrawal, Jeffrey J. Long, Aditya Kumar, Narayanan Neithalath

Materials Science and Engineering Faculty Research & Creative Works

Biofuel-based combustion synthesis (BCS) is a promising low-carbon pathway for decarbonizing cement production, providing an alternative to the fossil-fuel-driven clinkering process typically conducted at ∼1450 °C. Understanding microscale combustion mechanisms is essential to efficiently transfer biofuel-generated heat to cement precursors for targeted phase formation. Unlike previous studies focusing on macro-scale parameters such as fuel content/type, porosity, and holding temperature, this work provides mechanistic insights into microscale combustion behavior, linking microstructural phenomena with macro-scale processing conditions to guide parameter optimization. In-operando microscale imaging was employed to examine combustion wave propagation, spatio-temporal temperature evolution, and microstructural transformations within reactive pellets. Two combustion …

Evaluation Of Iron-Phosphate Glass–Ceramic Waste Form For Electrorefiner Salt Waste Simulant Dechlorinated With Phosphoric Acid, Harmony Werth, Paige Murray, Lucas Greiner, Jade Beland, Charmayne Lonergan, Brian Riley, Krista Carlson

Materials Science and Engineering Faculty Research & Creative Works

The importance of glass and glass–ceramic nuclear waste forms has been reaffirmed in recent years by the growing interest in nuclear power as a reliable energy source. Determination of processing methods for the disposal of halide-containing wastes will be essential for the advancement of nuclear technologies such as non-aqueous fuel reprocessing. Phosphate-based dechlorination and subsequent vitrification of radioactive salt waste into an iron-phosphate waste form have been identified as a potential processing scheme for electrochemical processing waste. The impact of H₃PO₄-based dechlorination of complex salt mixtures on the vitrification process and structure of the final iron-phosphate …

Effect Of Composition On Grain-Boundary Chemistry And Fracture Behavior In High-Entropy Carbides, Caleb Schenck, Marium Mostafiz Mou, Elizabeth Pritchett, Fu Yun Tsai, Josephine Hartmann, Michael Lastovich, Sam Daigle, Kayla Yano, Matthew J. Olszta, Sanjit Bhowick, Elizabeth Kautz, Gregory E. Hilmas, William G. Fahrenholtz, Donald W. Brenner

Materials Science and Engineering Faculty Research & Creative Works

High-entropy carbides (HECs) are often treated as a single material class defined by configurational entropy; however, their properties are governed by composition-specific defects and grain-boundary chemistry. This study demonstrates that substituting a single element can qualitatively change grain-boundary structure and fracture behavior in HEC ceramics. Two HECs, (Cr,Hf,Ta,Ti,Zr)C (HEC-Cr) and (Hf,Ta,Ti,W,Zr)C (HEC-W), were examined via electron microscopy, atom probe tomography, and molecular dynamics simulations. Simulations predict preferential segregation of Cr, W, and Zr to grain boundaries. Experiments confirmed Cr enrichment at grain boundaries and the formation of W-rich nanograins along boundary networks. Mechanical testing revealed that these compositional differences translated …

An Experimental Study Of The Morphology Of Dna-Carbon Nanotube Hybrid Structures In Direct Dna Sequencing, Avery P. Davis

Biomedical Engineering Undergraduate Honors Theses

Hybrid structures formed between single-stranded DNA (ssDNA) and single-walled carbon nanotubes (SWCNT) have emerged as promising components in future direct DNA sequencing technologies due to their unique morphological and electronic properties. The nanoscale configuration of these hybrids, including the DNA wrapping angle, pitch, and contour behavior, directly influences their potential for stable electronic readout. This thesis presents an experimental study of DNA-SWCNT hybrid morphology using a fixed, reproducible wrapping protocol designed to minimize environmental variability and isolate the influence of DNA nucleotide sequence on hybrid structure. As described in prior work, this protocol produces well-dispersed hybrids suitable for high-resolution imaging. …

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 …

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 …

Utility-Scale Battery Energy Storage Systems - Field Pilot Unit Experience, Analysis, And Review Of Technological Advancements, Kwabena A. Kyeremeh, Shaun E. Lavin, Grant M. Fischer, Dan M. Ionel, Aron Patrick

Electrical and Computer Engineering Graduate Research

Utility-scale Battery Energy Storage Systems (BESS) are becoming increasingly important in modern power systems, providing services ranging from backup support to load balancing and peak shaving. The long-term operational performance and reliability of these systems with expanding deployment remain insufficiently documented. This paper provides an operational assessment of a 1MW/2MWh utility-scale BESS alongside a systematic review of technology developments across major subsystems. Operational metrics including round-trip efficiency (RTE), outage characteristics, and degradation patterns are examined to identify performance trends and the underlying causes of outages. In addition, testing and operational principles aligned with utility practice and standards are presented to …

A Critical Review And Methodological Recommendations For Life Cycle Assessment Of Electrochemical Co₂ Mineralization, Dennis Dadzie, Kwame Awuah-Offei

Mining Engineering Faculty Research & Creative Works

Purpose: While researchers have relied on life cycle assessments (LCAs) to make claims about the environmental benefits of electrochemical CO₂ mineralization, no systematic review literature exists that synthesizes what we know about the LCA of electrochemical mineralization. This review aims to synthesize established knowledge on the LCAs of electrochemical CO₂ mineralization studies, identify research gaps and discuss challenges, and suggest guidelines for applying the ISO 14040/14044 LCA methodology in this sector. Methods: This paper undertook a comprehensive review of LCA studies on CO₂ mineralization with emphasis on electrochemical mineralization. We utilized relevant keywords based on the theme to search in …

Selective Extraction Of Nickel And Cobalt From Limonitic Laterite Via Optimized Sulfation Roasting–Water Leaching And Solvent Extraction, Maryam Osali, Farid Ahani, Mohammad Reza Aboutalebi, Mandana Adeli, Javad Moghaddam, Saeid Karimi, Janaka Jayamini Wijenayake, Lana Alagha

Mining Engineering Faculty Research & Creative Works

Limonitic laterites typically contain low Ni and Co contents and significant impurities, making the development of technical and economically feasible processes challenging. To address this challenge, this study investigates and evaluates an integrated hydrometallurgical process comprising sulfation roasting, water leaching, and solvent extraction (SX) for the selective recovery of Ni and Co from limonite-type laterite. Response Surface Methodology coupled with a Central Composite Design (RSM-CCD) was employed as a statistical experimental design tool to efficiently optimize the sulfation roasting conditions. Under the optimal sulfation roasting conditions (temperature 703 °C), selective leaching efficiencies of 87.2% for Ni and 96.6% for Co …

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 …

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 …

Boron Nitride Nanotubes Assist The Self-Assembly Of Spherical Cholesteric Liquid Crystal Shells Of Cellulose Nanocrystals In Water, Tanner L. Larson, Brandon J. Heppe, Benjamin S. Flavel, Ralph Krupke, Geyou Ao

Chemical & Biomedical Engineering Faculty Publications

Spherical confinement of cholesteric liquid crystal (ChLC) droplets is emerging as an intriguing approach for achieving complex ordered structures for photonic applications and beyond. Previously, this has been achieved primarily through microfluidic assembly utilizing immiscible solvents or immiscible mesogen-solvent systems, such as oil-water or thermotropic liquid crystal-water systems, respectively. Here, we show the spontaneous assembly of spherical ChLC droplets with isotropic cores from lyotropic liquid crystals of mixed nanorods containing boron nitride nanotubes (BNNTs) and cellulose nanocrystals (CNCs) in all-aqueous environments. We show that the mixing of as low as 0.094 vol % of pectin-coated BNNTs with isotropic dispersions of …

Harness: Hybrid Architecture For Resilience In Networked Engineering System Simulations, Daniel Scott

Graduate Theses and Dissertations

This dissertation presents the development of HARNESS, a unified, domain-agnostic framework for the modeling, optimization, and evaluation of complex systems under conditions of degradation and uncertainty. The research addresses a persistent challenge in systems engineering: the lack of a generalizable, behaviorally grounded approach for quantifying resilience and robustness across diverse domains. HARNESS integrates graph-theoretic dependency modeling, GPU-accelerated evolutionary optimization, and agent-based simulation into a modular architecture that enables both system design and diagnostic analysis. The framework models system interdependencies through user-defined components, parameters, and constraints, allowing architectures to evolve dynamically while maintaining structural validity. A mutation-only genetic algorithm with a …

An Energy- And Area- Efficient Two-Stage Latch Comparator Using Common-Mode Reset, Larry Yu

Electrical Engineering Theses and Dissertations

This thesis presents an energy-and-area-efficient two-stage comparator implemented in TSMC 65 nm CMOS that incorporates a Floating Inverter Amplifier (FIA) followed by a latch using a common-mode reset scheme. The FIA improves input sensitivity and reduces kickback noise by isolating the input nodes from large latch voltage swings. The proposed latch resets its output nodes to a common-mode voltage rather than one of its supply rails, thereby reducing switching energy during the reset phase. The comparator can resolve differential input voltages as small as 2 mV with a clock period of 500 ps, achieving 74.33 μV input-referred noise while consuming …

Optimization Of The Baffle Geometry Of A Circular Culvert Outlet Structure To Maximize Energy Dissipation, Kiarash Shirmahi

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

High-velocity flow at culvert outlets can lead to significant soil erosion and damage to downstream infrastructure, particularly in agricultural regions where land protection is critical. Circular culverts, commonly used in transportation systems, are especially susceptible to this issue due to flow acceleration caused by geometric constraints and installation angles. Despite extensive research on energy dissipation in rectangular culverts, limited attention has been given to circular configurations. This study addresses this gap by evaluating the hydraulic performance of baffle systems designed to reduce outlet energy in circular culverts.

A series of laboratory experiments was conducted using a scaled physical model of …

Modeling Structural Support To Facilitate Novel Treatments Of Degenerative Disc Disease, Jose Luis Calderon

Poster Presentations

Over 600 million people worldwide suffered from low back pain in 2020, with projections for 2050 being over 800 million [1]. Annual costs associated with low back pain total over 450 billion dollars in the US alone [2]. This research serves as a proof-of-concept for the use of structural supports to facilitate intervertebral disc healing. This treatment would involve the implementation of these supports along with existing injection treatments to promote regeneration. In both models, along with the combined model, the ability for these supports to alleviate intervertebral disc height loss is shown. This indicates that these supports would serve …

Recovery And Evaluation Of A Germanium Infrared Camera, Michael Paszek

Graduate Theses and Dissertations

Short-wave infrared imagers made of germanium are a promising way to extend silicon-compatible imaging beyond the visible spectrum. They also use mature CMOS fabrication and readout electronics. This thesis details the recovery, initialization, and evaluation of a germanium focal plane array (FPA) infrared camera system using both a sealed TriWave camera and a modular prototype platform. Functionality was restored to this legacy hardware, and repeatable testing workflows were established for evaluating packaged infrared imagers under controlled indoor and outdoor conditions. The prototype used a custom software interface named Merlott for evaluation, and it followed a standard sequence that included checking …

Polymer Charge Effects On Scaling In Membrane Distillation, Lucia Milans Del Bosch

Chemical Engineering Undergraduate Honors Theses

This research evaluates the effectiveness of polymeric inhibitors at suppressing scaling during direct contact membrane distillation (DCMD). Anionic polyacrylic acid (PAA), neutral polyethylene glycol (PEG), and cationic polyethyleneimine (PEI), were investigated. Experiments were conducted using both hypersaline single-salt and multi-component mixed-salt feeds to determine how the presence of different ions influences performance. Results from single-salt experiments showed that PAA and PEG effectively maintained permeate flux through chelation and steric hindrance, respectively, while PEI caused rapid membrane failure due to interfacial aggregation and pore wetting. In complex mixed-salt solutions, PEG was the additive, maintaining a steady flux with only a 7.33% …

Surface-Functionalized Silica Nanoparticles For Enhanced Bioavailability In Ophthalmic Mucoadhesive Drug Delivery Applications, Kaylee M. Drake

Chemical Engineering Undergraduate Honors Theses

This study investigates the stimuli-responsive behavior of porcine gastric mucin (PGM) as a model for the conjunctival mucous membrane of the human eye to optimize mucoadhesive ophthalmic drug delivery. As a versatile biopolymer, PGM has a dynamic matrix structure that functions as a selectively permeable barrier, regulating transport across mucosal membranes. To improve drug bioavailability and retention in ocular treatments, silica nanoparticles (SiNPs) were modified with varying surface functional groups and incorporated into the mucin at different physiological pH levels to examine the resulting microstructural changes. Leveraging the amphiphilic and negatively charged characteristics of mucin, positively charged and hydrophobic SiNPs …