Engineering Commons^™

High Frequency Dc-Dc Converter Design Optimization, Modeling And Control Based-Wbg Technology., Salah Ahmed Abdullah Eltief

Electronic Theses and Dissertations

The performance of DC-DC power converters is a cornerstone of modern electric vehicle (EV) powertrains, directly governing overall system efficiency, size, cost, and reliability. This dissertation presents a comprehensive performance analysis and optimization of DC-DC converter topologies to determine the most suitable design for high voltage EV applications. The evaluation rigorously compares efficiency, power losses, and physical size under a range of harsh operating conditions. A primary objective is to leverage Wide Bandgap (WBG) semiconductors, specifically Silicon Carbide (SiC), to push the performance boundaries of power conversion. While SiC devices are known for their superior material properties, a clear understanding …

Reproducibility In Modeling Of Knee Joint Mechanics, Maryam Nazem

Electronic Theses and Dissertations

Computational modeling of knee joint biomechanics can provide valuable insights into joint function, injury mechanisms, and patient outcomes, and can support surgical planning and informed clinical decision-making. However, achieving consistent and repeatable results, or reproducibility, is a significant challenge that affects the credibility of these models. This thesis addresses reproducibility through two studies related to the KneeHub Project, which is a multi-institutional collaboration designed to investigate reproducibility in finite-element modeling of the knee.

The first study involved model benchmarking, where predicted results of the calibrated models were compared with the experimental data to evaluate model reproducibility. While all models replicated …

Capacity, Allocation And Update Dynamics Of Human Memory Systems, Shaoying Wang

Electronic Theses and Dissertations

Information is encoded and stored in three types of memory: sensory memory (SM), short-term memory (STM), and long-term memory (LTM). SM has a large capacity but retains information for only a brief period. When information transfers to STM, only a limited amount can be stored. Information in STM can then be transferred to LTM, which has a much larger capacity and longer retention time. STM is often conceptualized as working memory (WM) to highlight its role in active information processing. Due to the limited capacity of STM, it is commonly believed that STM serves as the bottleneck for information processing. …

The Resonance Of Desire: A Sonic Exploration And Guide To Recreating Disney’S Signature ‘I Want’ Songs, Aiyanna E. Riley

Electronic Theses and Dissertations

This thesis explores the sonic architecture of Disney’s Renaissance-era “I Want” songs and develops a framework for recreating their signature production style. This study analyzes how vocal timbre, microphone choices, layering, stereo placement, and mixing strategies contribute to the immersive qualities that define the Disney sound. Drawing from historical accounts, interviews with industry professionals, and technical literature, the thesis documents production practices unexamined in scholarly work. Inspired by David Gibson’s The Art of Mixing, my analyses prioritize spatial and textural qualities in Disney mixes, highlighting how sound design shapes narrative impact. The study culminates in two original compositions modeled …

Developing Deep Learning Methods For Cognitive Impairment Detection Based On Non-Invasive Data, Muath Alsuhaibani

Electronic Theses and Dissertations

Cognitive impairment detection is on the rise to help reduce the burden of healthcare costs on institutions and individuals. Mild Cognitive Impairment (MCI) is an early stage of cognitive decline progressing to Alzheimer’s disease (AD) or AD-related Dementia (ADRD). Detecting the early stages of AD/ADRD is crucial for early interventions among older adults to mitigate cognitive decline over time. However, the current diagnostic methods are often costly and/or invasive, such as MRI and PET scans. Thus, the search for non-invasive and cost-effective screening tools for the early detection of cognitive impairment using speech, language, visual, and motor data is growing. …

Influence Of Obesity On Knee Joint Mechanics: A Subject-Specific Musculoskeletal Modeling Approach, Ryan C. Knowles

Electronic Theses and Dissertations

Obesity has been consistently linked to knee osteoarthritis (KOA), a debilitating joint disease. While prior work has shown that obese individuals often walk with altered biomechanics compared to normal-weight (NW) individuals, which may accelerate KOA progression, less is known about how these mechanics affect load distribution between the medial and lateral tibiofemoral (TF) compartments, particularly during higher-demand activities. This study developed subject-specific musculoskeletal models of five obese and five NW individuals, incorporating CT-based bone measurements and individualized joint contact points. Simulations were driven by six degree-of-freedom (6DOF) kinematics obtained from high-speed stereo radiography (HSSR) to predict TF loading and associated …

Equilibration And Transport Of Binary Mixtures On Planar And Porous Nanomaterials, Andrew Torres

Electronic Theses and Dissertations

We present results of a Kinetic Monte Carlo investigation of the adsorption dynamics of binary gas mixtures on planar and porous sorbents, with a focus on identifying and characterizing kinetic processes involved in uptake evolution and how they influence equilibrium conditions. We also investigate varying thermodynamic simulation parameters such as interactions, alkane lengths, partial pressures and pore configurations to determine how they impact these kinetic processes as well as equilibrium properties. This study matters both for better understanding how kinetics and equilibrium are connected and for improving practical techniques in separation applications. For planar surfaces, weak species overshoot kinetic processes …

Surgeon Ergonomics While Performing Total Knee Arthroplasty, Cameron Dahman

Electronic Theses and Dissertations

One of the most prevalent hazards to orthopedic surgeons are musculoskeletal disorders with 97% of arthroplasty surgeons reporting procedural-related musculoskeletal pain and 66% of orthopedic surgeons reporting procedural-related musculoskeletal injury [1], [2], [3]. With the annual number of total knee arthroplasties (TKA) on the rise, orthopedic surgeons are taking on larger annual caseloads and retiring later in life [4], [5]. The goal of this study was to quantify postural demand for 11 discrete surgical steps of TKA to identify ergonomically unfavorable positions surgeons experience while operating. Four orthopedic surgeons performed TKA while their motions were recorded using marker-based motion capture. …

Trauma Network Design Considering Patient Safety And Cost., Lin Lin

Electronic Theses and Dissertations

Trauma, as the leading cause of mortality and morbidity for those under the age of 45 in the US, incurs trillions in annual economic costs. The time-sensitive nature of trauma treatment necessitates an effective, coordinated regional trauma system to optimize patient safety. However, the financial burden associated with trauma care, especially due to low-insured population, presents a significant challenge to the financial health of trauma centers (TCs). To address critical challenges in this domain and provide much-needed insights to trauma decision-makers regarding their trauma system cost, network design, and subsidy policy, this dissertation proposes 3 contributions. First, we introduce an …

A Deep Learning Approach For Semantic Segmentation And Its Application On Ctc., Samir Farag Harb

Electronic Theses and Dissertations

This dissertation explores the modeling and analysis of medical images, focusing on the intricate task of colon segmentation and subsequent 3D reconstruction, which are critical steps in Computed Tomography Colonography (CTC) systems. The primary objective of this research is to develop precise segmentation approaches to enhance the accuracy of colon identification and reconstruction from abdominal CT scans. Three distinct segmentation approaches are proposed and evaluated: a Markov Random Field (MRF)-based approach, a convolutional neural network (CNN)-based deep learning (DL) approach, and a sequential episodic training with dual contrastive learning Approach (G-SET-DCL) that has a flavor of few-shot learning (FSL). To …

Optimization And Simulation Models For Integrating Social Determinants In Assessing And Optimizing The Accessibility And Efficiency Of Community Pharmacy Networks., Md Morshedul Alam

Electronic Theses and Dissertations

Community pharmacies are essential components of the healthcare system, serving not only as points of medication access but also as providers of health consultations and preventive care. However, disparities in pharmacy access persist due to a combination of geographic, socioeconomic, and behavioral factors. This dissertation develops a comprehensive methodological framework to evaluate and improve accessibility to community pharmacies, integrating optimization, choice modeling, and discrete event simulation. First, we develop an Optimal Community-Pharmacy Assignment (OCPA) model to quantify geographic accessibility across a regional population network. The model minimizes risk-adjusted travel distances between population centers and pharmacies, incorporating social determinants of health …

Design And Testing Method For Quality Control Of Chill Haze In Bourbon Production., Molly J. Wilburn

Electronic Theses and Dissertations

Chill haze is a quality issue in which white wisps and haze become visible in spirits when reaching sub 0℃ temperatures. Common quality control test methods rely on subjective visual tests and ambient temperature turbidity measurements. Currently there is limited access to commercial devices capable of reaching the sub 0 ℃ temperatures that are required for the formation of chill haze. This thesis focuses on the design, assembly and calibration of a custom-built turbidity meter capable of sub 0 ℃ temperatures and humidity control. The system uses an optical sensor at 90 ° to a light source to detect light …

Material Extrusion 3d Printing Of Metal Alloy: Material, Methods And Application., Sihan Zhang

Electronic Theses and Dissertations

Material extrusion (MEX) additive manufacturing presents a promising pathway for producing metal components with complex geometries while avoiding the safety hazards associated with loose powder handling in conventional metal additive manufacturing processes. This dissertation investigates the development and optimization of MEX processes for aluminum alloys, addressing critical challenges in feedstock formulation, printing parameter optimization, and post-processing strategies. Three distinct approaches were explored to advance the capabilities of aluminum MEX: filament-based processing of 6061 aluminum, paste-based extrusion of 6061 aluminum, and development of a novel aluminum-magnesium-tin alloy system for space manufacturing applications. The filament-based approach successfully demonstrated the production of 6061 …

Computational Fluid Dynamics And Fluid Structure Interaction Modeling In Healthy Vertebral Arteries: A Comparative Study, Bryce Clinkenbeard

Electronic Theses and Dissertations

Cerebral perfusion is critical for maintaining proper brain function, with each cerebrovascular artery playing an integral role in the overall cerebrovascular system. When these arteries become damaged or develop plaque, cardiovascular disease (CVDs) such as atherosclerosis can arise, leading to conditions like arterial stenosis. While CVDs are most prevalent in older individuals, they are also observed in young adults, particularly those engaged in high-endurance occupations such as military service. Diagnosis and prediction of CVDs often rely on imaging modalities supported by computational fluid dynamics (CFD) which account for low resolution in fluid flow. CFD models assume rigid arterial walls, which …

Development Of An Embedded Iot Board For Real-Time Floor Estimation Of Autonomous Robots, Carter J. Sorensen

Electronic Theses and Dissertations

As service robots become more prevalent in multi-story environments such as hospitals, hotels, and laboratories, accurate floor-level detection is critical to ensuring operational reliability. Consider a robot tasked with delivering medical samples in a multi-story laboratory. Without accurate feedback, a robot exiting on the wrong floor could introduce delays, disrupt workflows, or compromise sample integrity. Internet of Things (IoT) technologies offer a way to address these risks by providing real-time error detection and corrective capability. However, current IoT-based floor estimation systems often require invasive modifications to building infrastructure—particularly elevator control panels. These approaches introduce challenges related to cost, liability, backward …

An Advanced Hexacopter For Autonomous Exploration Of Mars: Attitude Control And Navigation Strategies, Laura Sopegno

Electronic Theses and Dissertations

Mars exploration has recently witnessed major interest within the scientific community. Unmanned robotic platforms offer reliable solutions to acquire and collect data and information from the Red Planet. Particularly, rovers, landers, and orbiters have significantly shaped planetary exploration on the Moon and Mars, contributing significantly to past missions while also highlighting limitations in their capacity to cover diverse terrains over wide ranges. Given current advances in Unmanned Aircraft Systems (UASs), Unmanned Aerial Vehicles (UAVs) offer promising alternatives for future scientific missions.

It is argued that hexacopters, with their relatively compact design and redundancy, present a promising …

Feasibility Analysis For The Implementation Of An Anaerobic Digestion System In The City Of Pittsburgh, Pa, Gianna L. Kolencik

Electronic Theses and Dissertations

The current study is investigating the feasibility of an anaerobic digestion system

in Pittsburgh, Pennsylvania, at the old State Correctional Institute (SCI-Pittsburgh)

located at 1922 Westhall St. This location is immediately upstream of the Allegheny

County Sanitary Authority (ALCOSAN) along the Ohio River. Municipal solid waste

from ALCOSAN may be used as the main form of feedstock. ALCOSAN produced

roughly 36,500 tons of dry sludge in the reporting year 2023-2024. Based on the volume

of dry sludge from ALCOSAN it is estimated that an anaerobic digestion system could

yield approximately 29,930,000 kWh of energy, which is enough to power over …

Alterations And Improvements Of The Photoacoustic Flow Cytometry Method, Nicholas J. Taylor

Electronic Theses and Dissertations

The emergence and proliferation of antibiotic-resistant bacteria present a significant and growing challenge to global public health, with the potential to render many existing antibiotics ineffective. Infections caused by these resistant pathogens are difficult to treat, resulting in higher morbidity, mortality, and healthcare costs. A major obstacle in combating these infections is the slow pace of traditional diagnostic methods, such as blood cultures, which typically take 2-3 days to identify the causative bacteria and determine their antibiotic resistance profiles. This delay in diagnosis hinders timely interventions and appropriate treatment, further contributing to the spread of resistant infections. As such, there …

A Causal Model Of Performance Shaping Factors For Human Reliability Analysis In Manufacturing., Prameet Ranjan Jha

Electronic Theses and Dissertations

Human reliability analysis is a critical component of probabilistic risk assessment, aimed at predicting and mitigating human errors in complex systems. This dissertation develops a novel approach to human reliability analysis in manufacturing by integrating structural equation modeling and Bayesian networks to improve the estimation of human error probabilities. Traditional human reliability assessment methods, such as the Standardized Plant Analysis Risk-Human Reliability Analysis (SPAR-H) and the Technique for Human Error Rate Prediction (THERP), provide structured techniques for estimating human error probabilities. However, these methods often fail to capture the complex interdependencies among performance shaping factors (PSFs), limiting their applicability in …

Deep Learning In Lung Cancer Pre- And Post-Radiation Therapy: Diagnosis Of Malignancy And Radiation-Induced Lung Injury From 3d X-Ray Ct., Benjamin Peter Veasey

Electronic Theses and Dissertations

Lung cancer remains the leading cause of cancer-related mortality worldwide, with early detection and accurate diagnosis being critical for improving patient outcomes. Additionally, the progression of Radiation-Induced Lung Injury (RILI) following Stereotactic Body Radiation Therapy (SBRT) for lung cancer presents a significant diagnostic challenge. This dissertation addresses these challenges by developing deep learning-based diagnostic tools for both pre-treatment lung nodule malignancy classification and post-treatment RILI identification using 3D X-ray CT imaging. The research is divided into two primary objectives. First, for lung nodule malignancy classification, we developed a biopsy-confirmed dataset, called NLSTx, to train and evaluate deep learning models while …

Online Optimization With Lookahead For Dynamic Assignment And Energy-Smart Scheduling In Manufacturing., Mahmud Parvez

Electronic Theses and Dissertations

Scheduling in online and dynamic manufacturing systems presents significant challenges due to the continuous arrival of customer orders with certainty only over a short time window and the dynamic availability of resources after completing ongoing operations. Similar challenges exist at our industry partner’s site when scheduling orders (computer servers) to machines (testing cells) during the final testing process before customer delivery. The primary challenge lies in dynamically assigning incoming orders to available machines in order to minimize the number of unfinished orders. Additionally, the energy-intensive nature of the production process introduces another challenge; efforts to reduce energy consumption often lead …

Thermal Characterization Of Lithium-Ion Batteries Under Fast Charging Conditions Using Infrared Imaging., Gowthaman Punithakumar

Electronic Theses and Dissertations

Lithium-ion batteries are widely used across various industries due to their long lifespan, high energy density, low self-discharge rate, and absence of memory effect. However, fast charging of Li-ion batteries can cause problems like lithium plating, mechanical damage, and overheating. Temperature plays a key role in battery performance. Measuring temperature accurately is important to improve battery life, efficiency, and safety. However, accurately measuring a battery's internal temperature remains challenging, and the appropriate measurement method depends on factors like range, accuracy, resolution, and cost. Choosing the right temperature measurement method depends on range, accuracy, resolution, and cost. In this study, we …

Engineering Solutions For The Transplant Supply Gap: Social Network Analysis, Artificial Intelligence, And Optimization In Living Kidney Donation., Joshua Nielsen

Electronic Theses and Dissertations

Kidney transplantation is the gold standard for treating end-stage renal disease, yet over 90,000 patients remain on the transplant waitlist. This dissertation introduces engineering-driven solutions to help reduce the transplant supply gap by addressing three challenges: illicit trafficking, donor recruitment, and evaluation inefficiencies. First, we model illicit organ trafficking networks using social network analysis. We demonstrate that targeting transplant clinics alone is insufficient to disrupt operations. Instead, disrupting the network requires detaining brokers who organize behind-the-scenes logistics—offering a more effective strategy for intervention. Second, we seek to identify a latent population of potential living donors who face barriers such as …

Development Of A Portable Electroencephalogram With Display, Seth D. Davis

Electronic Theses and Dissertations

In this experiment, the goal was to design, build, and test an Electroencephalogram (EEG) circuit that would then be paired with a touchscreen display as a portable unit for use in Schizophrenic research at East Tennessee State University at the Quillen College of Medicine. The requirements for this prototype denoted that the device had to be able to obtain a signal from two electrodes placed on the head of an individual with a third attached to the ankle as a ground, amplify and filter the signal, and display the results on a touchscreen display for recording and analyzing. The circuit …

Exploring The Impact Of Social Interactions And Representation On The Development Of Engineering Students' Sense Of Belonging In A Summer Program., Liliana Martinez

Electronic Theses and Dissertations

Research has shown that engineering students from underrepresented minority (URM) populations experience significant retention gaps compared to their majority peers (Dickerson et al., 2014). One factor that can significantly promote academic success, retention, persistence, and psychological adjustment is a sense of belonging (Hausmann et al., 2007; Hoffman et al., 2002). There is evidence showing that Summer Bridge Programs (SBPs) can foster students’ sense of belonging (Strayhorn, 2019); however, little is known about the mechanisms through which an SBP impacts URM engineering students’ sense of belonging. This study addresses this knowledge gap by investigating the impact of the Brown Forman …

Multimodal Emotion Recognition For Human-Robot Interaction Across Neuro-Diverse Populations., Ruchik Mishra

Electronic Theses and Dissertations

This dissertation explores the integration of multimodal data streams and artificial intelligence pipelines to understand human affect in neurotypical and children with Autism Spectrum Disorder (ASD). This dissertation captures human affect in the context of human-robot interaction. For this, multiple studies have been presented with both children with ASD and neurotypical adults. This dissertation makes four contributions: 1) The first study introduces autonomy during perspective-taking teaching sessions by making verbal content generation through large language models (LLMs). This system is the first of its kind for teaching perspective-taking in a semi-autonomous manner under the supervision of domain experts. Furthermore, this …

Applying Residence Time Distribution Theory To Coronary Thermodilution Curves., Jacob Michael Miller

Electronic Theses and Dissertations

Cardiovascular diseases remain the leading cause of death worldwide and coronary microvascular dysfunction is one cardiovascular disease which is particularly challenging to diagnose and treat. Coronary thermodilution is a widely used, invasive procedure to evaluate microvascular function by generating physiological indices such as coronary flow reserve and the index of microvascular resistance. Although commonly cited as an indicator dilution method in the cardiovascular literature, current coronary thermodilution techniques lack rigorous application of the accompanying mathematical framework, thereby leaving potentially valuable diagnostic information unexploited. This study bridges that gap by demonstrating the equivalence between indicator-dilution theory and residence time distribution theory …

An Automatic Colorectal Polyps Detection Approach For Ct Colonography., Mohamed Yousuf

Electronic Theses and Dissertations

Colon cancer, also known as colorectal cancer, is a significant health concern, with increasing incidence rates, particularly among individuals under 50. This rise has led experts to recommend the introduction of regular screenings at 45 years of age for adults at average risk. Early detection through such screenings can identify precancerous polyps, allowing their removal before they develop into cancer. This proactive approach has the potential to reduce colorectal cancer deaths by up to 60%. In addition, research indicates that people diagnosed before age 50 have better survival rates, which emphasizes the importance of early diagnosis. Therefore, adhering to recommended …

Biomechanical Assessment Of Fracture Risk In Young Children With Healthy Bone And Osteogenesis Imperfecta., Keyonna Mckinsey

Electronic Theses and Dissertations

Osteogenesis imperfecta (OI) is a group of genetic bone disorders that can range from a mild increase in fractures in one’s lifetime to perinatally lethal. Biomechanical assessment via finite element analysis (FEA) can be used to provide subject specific evaluation of fracture risk and thus aid in furthering understanding of likelihood of fracture due to loading associated with common daily activities. Thus, the purpose of this dissertation research was to characterize the risk of femur fracture in young children with OI compared to that of healthy children when exposed to loading associated with common activities, specifically gait. To accomplish this, …

Bayesian Model Updating Of Structural Parameters Using Temperature Variation Data., Ujjwal Adhikari

Electronic Theses and Dissertations

Physical digital twins have now emerged as a technology in structural health monitoring and other domains of structural modeling. A Finite Element Model can be a tool for digital twin technology in conjunction with measured physical data. Developing an accurate digital model requires the integration of various parameters to replicate the real structure; however, temperature is dynamically changing, resulting in difficulty in the identification of structural parameters. Typically, temperature is considered noise or filtered out. Limited research has addressed the physics-based model using temperature variation related to structural modal properties. Finite Element Model Updating (FEMU) is a typical inverse problem-solving …