Engineering Commons^™

Reinforcement Learning For High-Dimensional Tradespace Exploration In Multi-Objective Optimization, Aaditya Kothavade

All Theses

Engineering design optimization often requires balancing multiple competing objectives while navigating complex, high-dimensional tradespaces. Despite significant advances in tradespace exploration techniques, current methods face critical challenges in efficiently navigating high-dimensional design spaces. As the number of design variables and competing objectives increases, traditional multi-criteria decision-making and optimization methods struggle to explore the vast solution space comprehensively. The curse of dimensionality exacerbates this issue, making it impractical to analyze all possible solutions and effectively identify trade-offs between objectives. Additionally, the computational complexity of high-dimensional spaces further complicates optimization, making exhaustive solution analysis infeasible. Traditional multi-objective optimization methods rely on static Pareto-front …

Stability Of Holes In Granular Raft, Plabon Kumar Saha

All Theses

A granular raft at an oil–water interface exhibits unique mechanical properties, including the ability to form and sustain stable holes. In this study, we experimentally investigate the formation, stability, and collapse dynamics of holes in particle rafts composed of micrometer-sized particles. Holes are created using a hollow cylinder, which generates a meniscus that inhibits particle motion, thus stabilizing the hole. Stable holes are formed when their size reaches a critical value, which depends upon the capillary length. The critical hole size does not depend upon the circularity of the hole. We show that capillary forces due to the presence of …

False Information Attack Detection In A Connected Vehicle Environment With Quantum Inspired Long Short-Term Memory, Jean Michel M. Tine

All Theses

Wireless communication Systems enabling Vehicle-to-Vehicle (V2V) and Vehicle-to-Infrastructure (V2I) data exchange, supported by technologies such as Cellular-V2X (C-V2X), has introduced significant cybersecurity challenges, particularly the threat of false information attacks that can compromise traffic safety and efficiency. In this thesis, the author focuses on identifying false information cyber-attack on V2I, in which vehicles are sending Basic Safety Messages (BSMs) to a Roadside Unit (RSU) and RSUs are collecting, processing and communicating data back to Connected Vehicles (CVs) to support different CV applications. Despite advances in anomaly detection using Long Short-Term Memory (LSTM) networks, these models often struggle with computational efficiency …

Berm-Leveling Machine For Peach Orchards: Incorporation Of Tree-Sensing Feature And Profitability Study, Shubham Singh

All Theses

Root collar excavation extends the productive life of peach trees in Armillaria root rot-infested soil, but the process requires trees to be planted on berms. Berm-planted peach orchards restrict the mobility of workers and machinery and can lead to increased erosion in furrows on either side of the berms. The current inter-tree berm-leveling machine depends on the driver's command to dodge the peach trees. The objectives of this thesis were to (1) integrate the feeler, infrared, and LiDAR-based tree sensing systems in the berm-leveling machine to make the soil excavating head's movement independent, (2) measure the impact of finger weeder-based …

Micro Wind Turbine - Modelling And Testing, Mohammad Uzair Bhati

All Theses

The global energy demand continues to rise as people consume more electricity to power their personal electronics, electric vehicles, and consumer products such as outdoor tools. To generate renewable energy, large scale solar and wind farms continue to receive the most commercial attention. However, portable wind energy turbines have the potential to generate sufficient power for cell phones and other electronic devices. There are two types of wind turbines, horizontal and vertical axis each having their pros and cons. Vertical-axis wind turbines are the main focus of this thesis, with a reduction in their form factor or size and portable …

Lightlink: Visible Light Communication For Batteryless Devices With Variable Computational Load, Charles Phillips

All Theses

Visible Light Communication (VLC) devices have been experimentally proven to work as a suitable communication medium for batteryless devices. However, the effects of practical load have yet to be fully explored. To that end, we have developed LightLink, a new MAC and PHY layer protocol for VLC within batteryless devices, and have studied various ways that computational load can affect transmission accuracy in realistic scenarios. Our key findings point us towards an adaptive VLC reception system based on inferred environmental variables.

An Experimental And Computational Study Of High-Temperature Creep Behavior In Fully Lamellar Titanium Aluminide Alloys, Karel M. Ziminsky

All Theses

Titanium aluminide alloys have seen increased aerospace applications in recent years, especially in aircraft jet engines. They can offer benefits such as improved high-temperature strength compared to titanium alloys and reduced density compared to nickel alloys. These alloys also can exhibit high creep resistance due to their fully lamellar microstructure. These mechanical properties are desirable for components like turbine blades, where tight tolerances must be maintained for optimal performance. This research examines the high-temperature creep behavior of a fully lamellar two-phase titanium aluminide alloy, TNM® (Ti-43.5Al-4Nb-1Mo-0.1B), through experimental and computational methods. Scanning electron microscopy studies reveal the presence of large …

Developing Reduced Order Models For Gas Bubble Formation In Irradiated Metals Using Integrated Phase Field Modeling And Koopman Operator Theory, John M. Eggemeyer V

All Theses

Irradiation damage in materials is prevalent in nuclear components, posing significant risks in the safety and reliability of nuclear reactors. Phase field models offer a versatile framework for modeling irradiation damage in materials at mesoscales. Such high fidelity method has been used to model the formation of fission gas bubbles superlattice, a microstructure array occurs at certain irradiation conditions (dose, dose-rate, and temperature). To overcome the high computational cost of phase field modeling, Koopman operator theory is applied to create reduced order models, allowing for instantaneous simulations of fission gas bubble behaviors. These low fidelity models are integrated into machine …

Evaluating The Role Of Electrostatic Forces In The Adsorption Of Perfluoroalkyl Substances To Granular Activated Carbon, Thomas A. Mccall

All Theses

In response to new drinking water regulations announced by the EPA in 2024, many municipalities will need to monitor concentrations and implement new treatments to address PFAS, a class of anthropogenic organic contaminants. A leading technology for this application is GAC adsorption due to its familiarity and availability. The adsorption of four PFAS species (PFBA, PFBS, PFOA and PFOS) to Calgon Filtrasorb400 (F400) was evaluated for a range of pH and ionic strength conditions to investigate the role of electrostatic interactions in adsorption capacity. These PFAS are all strong acids, so pH was used as a control for GAC surface …

Graph Based Deep Reinforcement Learning Aided By Transformers For Multi-Agent Cooperation, Michael S. Elrod

All Theses

Mission planning for a fleet of cooperative autonomous drones in applications that involve serving distributed target points, such as disaster response, environmental monitoring, and surveil- lance, is challenging, especially under partial observability, limited communication range, and uncertain environments. Traditional path-planning algorithms struggle in these scenarios, particu- larly when prior information is not available. To address these challenges, I propose an innovative framework that integrates Graph Neural Networks (GNNs), Deep Reinforcement Learning (DRL), and transformer-based mechanisms for enhanced multi-agent coordination and collective task ex- ecution. My approach leverages GNNs to model agent-agent and agent-goal interactions through adaptive graph construction, enabling efficient …

Blockchain-Integrated Version Control For Secure And Transparent Software Supply Chains, Iwinosa W. Aideyan

All Theses

The software supply chain encompasses all stages of software development and delivery from initial coding and version control to integration and deployment. As development environments become increasingly distributed and reliant on external dependencies, ensuring the integrity, auditability, and consistency of code changes has become a pressing challenge. Traditional version control systems like Git, while effective for collaboration and tracking revisions, do not inherently provide tamper-evident commit histories. Features such as history rewriting (e.g., git rebase, git push --force) can be exploited to manipulate commit logs without detection, posing risks in security-sensitive domains. This thesis proposes a blockchain-integrated version control framework …

Privacy Implications Of Data Collection In Android Automotive Os, Bulut Gözübüyük

All Theses

Modern vehicles have become sophisticated computational and sensor systems, as evidenced by advanced driver assistance systems (ADAS), in-car infotainment, and autonomous driving capabilities. They collect and process vast amounts of data through various onboard subsystems. One significant player in this landscape is Android Automotive OS (AAOS), which has been integrated into over 100 million vehicles and has become a dominant force in the in-vehicle infotainment (IVI) market. With this extensive data collection, privacy concerns have become increasingly crucial. The volume of data gathered by these systems raises questions about how this information is stored, used, and protected, making privacy a …

Gene Editing Combined With Apap Diet-Mediated Selection In A Ldlr-/- Mouse Model Of Familial Hypercholesterolemia, Pramita Suresh

All Theses

Cell-based gene therapy has garnered significant interest in treating familial hypercholesterolemia (FH), an autosomal co-dominant disorder characterized by elevated low-density lipoprotein cholesterol (LDL-C) levels. However, achieving a therapeutic threshold level of engraftment of gene-modified cells is a significant hurdle. In FH, as in most liver diseases, the transplantation of healthy gene-modified hepatocytes does not result in a selective advantage for the healthy hepatocytes over native hepatocytes for clonal expansion in the liver. In FH, as in most liver diseases, the transplantation of healthy gene-modified hepatocytes does not provide a selective advantage for the healthy hepatocytes over native hepatocytes regarding clonal …

Defining Fidelity For Tradespace Application, Aditya Agrawal

All Theses

This research proposes a definition of tradespace fidelity and presents a study on its effectiveness in the tradespace. Tradespace exploration helps evaluate various design options, allowing engineers to make informed decisions in early design stages. Fidelity generally refers to how closely a model approximates reality. However, the definition of fidelity has been inconsistently defined and interpreted in various contexts concerning particular problems. In some cases, it is a measure of accuracy; in others, information; in another, uncertainty; and in others, computational complexity. Fidelity is poorly and inconsistently defined in the literature. In general, higher fidelity models tend to be more …

A Parametric Study Of Compact Wind Borne Debris In Tornadoes, Akash Yadav

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Debris lofted and transported by tornadoes is a significant source of damage during these storms. Several approaches have been taken to model such debris flight, ranging in complexity from fine-scale CFD simulations to coupling the compact debris flight equations with simplified analytic models for the tornado vortex. Both approaches have their merits, though the latter comes with significantly lower computational costs. Despite the simplifications, this second approach has successfully captured details of debris flight events established in post-tornado forensic surveys. Herein, we take advantage of the low computational cost of the latter approach to undertake a detailed parametric study of …

Mechanistic Insights Into Polymer-Assisted Graphene Exfoliation: The Roles Of Velocity, Adhesion, Cohesion, Temperature, Peeling Mode, And Edge Defect Via Coarse-Grained Molecular Dynamics, Linjiale Dai

All Theses

Graphene exfoliation is a critical step in the fabrication of high-quality graphene

layers. However, the underlying fracture mechanisms remain poorly understood. In this

work, I employed coarse-grained (CG) molecular dynamics (MD) simulations to

investigate how factors such as interfacial binding energy, substrate cohesion, temperature,

peeling mode, and edge defects influence the outcome of the exfoliation process. To model

polymer-assisted mechanical exfoliation, I used a finite-size system in which multilayer

graphene (MLG) is sandwiched between two thin polymer films. Leveraging the

spatiotemporal efficiency of the CG model, I performed fifty simulation iterations per

parameter set and analyzed the results from a …

Understanding And Modeling Pooled Rideshare Acceptance: Influential Factors, Preferred User Experiences, And Implications, Rakesh Gangadharaiah

All Dissertations

Ridesharing allows people to share a vehicle with others traveling in the same direction, which can reduce costs and traffic congestion. Pooled rideshare (PR) services, such as UberX Share and Lyft Shared, offer an economical and environmentally friendly alternative by matching passengers traveling similar routes. However, despite these benefits, PR adoption remains low due to concerns about safety, privacy, and convenience. This research explores the factors influencing PR adoption and provides recommendations to improve user acceptance. A nationwide survey of 5,385 participants across the U.S. was conducted to understand why people choose or avoid PR. The study identified five key …

User Acceptance Of Shared Autonomous Vehicles, Haotian Su

All Dissertations

A dissertation is proposed to explore user acceptance of shared autonomous vehicles (SAVs). SAVs are facing limited user acceptance. To systematically tackle the user acceptance barriers of SAVs, the main problem can be disintegrated into two sub-problems of user acceptance of autonomous vehicles (AVs) and ridesharing. The comfort of the ride experience in AVs is a determinant of user acceptance. Understanding the influential factors and developing methodologies to quantify human comfort in AVs are essential to facilitating future research to improve human comfort in AVs. The current pooled rideshare (PR) service closely resembles the anticipated future of SAVs. Understanding why …

Understanding The Role Of Ligamentous Constraint In Trapeziometacarpal Pathomechanics, Lizzie Walker

All Dissertations

The trapeziometacarpal (TMC) joint is the most common site for osteoarthritis (OA) in the upper limb. This joint is characterized by its wide range of motion and limited bony stability, making it susceptible to OA. The TMC joint relies mostly on ligaments and muscles for its static and dynamic stability, respectively. While importance of both volar and dorsal capsular TMC stabilizers has been demonstrated, the role of TMC ligamentous tissues in the development of thumb basal joint OA remains unclear.

The goal of this work was to identify morphometric and mechanical changes in key TMC ligament stabilizers, including the volar …

Development Of Rolipram Loaded Pgp Nanoparticles For Spinal Cord Injury Repair, Zhen Liao

All Dissertations

Spinal cord injury (SCI) leads to devastating neurological deficits due to primary mechanical damage and secondary injury mechanisms, including inflammation, oxidative stress, excitotoxicity, and inhibitory scarring, which collectively impede neural regeneration. One key aspect of SCI pathology is a significant reduction in cyclic adenosine monophosphate (cAMP) levels, primarily due to increased phosphodiesterase (PDE 4) activity. As a ubiquitous second messenger, cAMP regulates key signaling pathways, including protein kinase A (PKA) / cAMP response element-binding protein (CREB) and exchange protein activated by cAMP 2 (EPAC2). Therefore, restoring/increasing cAMP level is one of the major therapeutic strategies to reduce neurotrauma and restore …

The Effects Of Cigarette Smoke Extract On Osteoarthritis In A Primary Joint Tissue Explant Model, Emily Sawvell

All Dissertations

Osteoarthritis (OA) is the most common degenerative joint disease in the world with an economic burden of nearly $140 billion annually. Factors identified to increase the risk of developing OA include age, obesity, sex, race, genetics, and previous joint injury. However, one risk factor that has been scarcely studied in OA etiology is cigarette smoking. While some studies have reported smoking to protect against OA, increasing evidence suggests that cigarette smoking results in more severe and painful OA, increases the rate of developing OA, and reduces the efficacy of pain medications and arthritis-targeting therapies. Despite this, the impact of cigarette …

The Evolution Of Nanoparticles In Nanoparticle Doped Optical Fibers, Mary Cahoon

All Dissertations

Optical fiber and fiber laser technologies based on silica glass are critical to many technologies today. One method to improve the optical performance of laser fibers is engineer the local environment around the active elements in the glass. To that end, this Dissertation focused on the fabrication and characterization of fibers made with nanoparticles incorporated into the glass to control the local composition. First, the nanoparticle composition and structure was analyzed as it evolved from from the initially-synthesized form to incorporation into the dense aluminum-silicate glass. The aluminum oxide in the glass was found to be important not only to …

Development Of Translational Microscale Systems To Interrogate How Biophysical And Biochemical Cues Alter The Phenotype Of Hormone Positive Breast Cancer, Braulio Ortega Quesada

All Dissertations

Cancer is a complicated disease and one in every three diagnoses are women with breast cancer. Recent research shows that the progression of cancer depends strongly on interactions with other non-cancerous cells and non-cellular components. Metastasis, the spread of cancer to other parts of the body, is a key step in cancer progression and makes treatment harder, leading to poor response to treatments culminating in death in ~90% of patients. This dissertation focused on creating a series of microdevices as novel pre-clinical models of breast cancer. Two different devices were fabricated to (1) study how exposing cancer cells to the …

Decision Space Decomposition For Multiobjective Programs, Emma Soriano

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Being inspired by the parametric decomposition theorem for multiobjective optimization problems (MOPs) of Cuenca and Miguel (2017), and by the block- coordinate descent for single objective optimization problems, we present a decom- position theorem for computing the set of minimal elements of a partially ordered set. This set is decomposed into subsets whose minimal elements are used to retrieve the overall minimal elements. We apply this approach to strictly convex MOPs de- composing their decision space into lines. The line decomposition benefits from the fact that a multiobjective line search problem is equivalent to solving a collection of single objective …

Learning Through Online Participation: From Breakout Rooms To Discord, Makayla Moster

All Dissertations

For software development teams, teamwork is an essential part of their day-to-day lives. However, due to the aftermath of the COVID-19 pandemic, more companies have allowed employees to have more hybrid and remote work options than before. As more companies are adopting hybrid and remote workstyles, we need to ensure that we are preparing the next batch of young software developers to conduct teamwork in remote and hybrid settings. In this dissertation, I address the tools students use for teamwork and how to improve their teamwork inside and outside of the classroom. I present my research on improving student experiences …

Adaptive Delay Compensation Frameworks For Distributed Real-Time Co-Simulation In Power Systems, Elutunji Buraimoh

All Dissertations

This dissertation presents a model-free, adaptive delay prediction and compensation framework for geographically distributed real-time power system co-simulation environments. Communication delays—both constant and real-time-varying—significantly degrade the accuracy, fidelity, and stability of co-simulated systems, particularly in dynamic and transient analyses of partitioned power systems. To address this, a predictor-based framework is developed that compensates for delays without requiring system models, computationally intensive signal transformations, or manual intervention.

The proposed solution leverages a Damping Impedance Method as the interface algorithm, combined with a sliding-mode control-inspired predictor system. Both single-parameter and multi-parameter predictor configurations are implemented, with the multi-parameter design providing an additional …

Toward The Application Of Natural Language Processing In Electronic Health Record Analysis For Taxonomy Development, Latoya Mcdonald

All Dissertations

Electronic health records (EHRs) are pivotal resources for nurse practice because they increase the timeliness and reliability of patient information at the point of care and support access by multiple healthcare providers and the individual patients themselves. However, it is widely recognized that data extraction from EHRs is challenging due to the variability in the language used in clinical care notes and the lack of standardized terminology across healthcare systems. The broad objective of this dissertation is to develop taxonomy-based classification models for nursing care by applying feature engineering approaches to EHRs that include nursing care of ostomy patients following …

Real-Time Active Thermal Management And Degradation Forecasting Of Power Electronics Building Blocks In All-Electric Ships, Ali Moghassemi

All Dissertations

With advancements in semiconductor technology, power electronic devices play a critical role in modern power systems, enabling efficient energy conversion in applications such as renewable energy integration, electric vehicle drives, industrial automation, and Navy ship power systems. However, the increasing use of power converters presents challenges such as harmonic reduction, cost optimization, reliability improvement, and thermal management, especially in weight- and space-constrained environments like wind turbines and shipboard systems. High-frequency switching, while reducing passive filter size, increases thermal stress on semiconductor devices, impacting efficiency and longevity. Active thermal control, which regulates junction temperature through power loss management, and degradation forecasting, …

Ex Vivo Multiplex Knockdown Of Angptl3 And Cypor In Hepatocytes As A Novel Cell Therapy For Familial Hypercholesterolemia, Callie D. Clark

All Dissertations

Inherited metabolic diseases (IMDs) affect approximately 1 in 800 individuals. The only curative treatment for IMDs is liver transplantation. However, transplantation carries significant risks, including organ rejection and a lifelong need for immunosuppression. Therefore, gene editing has emerged as a promising alternative to liver transplantation for treating IMDs.

Familial hypercholesterolemia (FH) is and IMD characterized by elevated LDL-C levels resulting in premature cardiovascular disease. CRISPR-Cas9-mediated gene editing to disrupt the gene encoding angiopoietin-like 3 (ANGPTL3) in the liver represents a novel therapeutic approach for FH. Nonviral delivery performed ex vivo is safer than systemic delivery because gene editing is in …

Ceramic Membrane Evaluation Via Automated Filtration Systems For Water Treatment And Resource Recovery, Weiming Qi

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Membranes are an advanced and mature water and wastewater treatment technology. Membrane fouling is a key difficulty for all membrane filtration processes, leading to significant attention in the literature over the years. A common problem in laboratory-scale membrane research is that the testing methods in the laboratory are often quite different than industrial applications due to the limitations of manual experimental setups. An automated membrane filtration apparatus was built in the lab to solve this problem by allowing long-term filtration, frequent backwash and CIP, and high-accuracy operation. The filtration system achieves different cleaning strategies for both theoretical research and practical …