Engineering Commons^™

A 10 Kv Sic Mosfet Power Module With Optimized System Interface And Electric Field Distribution, Xiaoling Li

Graduate Theses and Dissertations

This dissertation introduces a holistic and systematic design methodology tailored to the 10 kV silicon carbide (SiC) MOSFET power modules to achieve multi-objective optimization with enhanced electric-field (E-field) distribution, minimized common-mode (CM) parasitic capacitance, and reduced system-level parasitic inductances. The proposed approach encompasses two innovative techniques: 1) an electric-potential-oriented module-system interface to reduce system-level parasitic inductance while maximizing insulation capability; 2) stacked substrates with patterned middle layer copper to alleviate the E-field concentration at the triple-point and reduce the maximum E-field without compromising on thermal resistance. The effectiveness of these innovative approaches is substantiated through the development of a 10 …

Towards Side-Channel Infrastructure For Software Implementations Of Pqc Algorithms, Tristen Teague

Graduate Theses and Dissertations

Post-Quantum Cryptography (PQC) is a new class of asymmetric cryptography algorithms that are supposed to be secure against both classical computers and quantum computers through Shor’s algorithm. Since PQC algorithms are currently being standardized, they will replace older standardized asymmetric algorithms (such as RSA) and will be deployed within the digital infrastructure. Before implementations of the PQC algorithms are placed into the infrastructure, they must undergo evaluation of both performance and security. One such security issue that needs large investigation before deployment are side-channels. Side-channel attacks (SCA) are a method of gathering information from the implementation, such as power-consumption and …

Design And Implementation Of High-Frequency Dc-Dc Converters For Ev Applications, Rahul Biswash

Graduate Theses and Dissertations

The power electronics industry has been revolutionized by introducing wide bandgap semiconductor devices, such as Silicon Carbide (SiC) and Gallium Nitride (GaN). Due to their high frequency, high temperature, and high voltage operating capabilities, wide bandgap devices boast significant improvements in power density, efficiency, and reliability, as evidenced by their ability to decrease the size of power converters by operating at higher frequencies, temperatures and voltages, use of smaller and less passive components, such as transformers, inductors and capacitors, which makes power converters more compact and light-weight, ideal for space and weight-constrained applications, and compatibility with a wide range of …

Hierarchical Power Converter Physical Design, Tristan Mark Evans

Graduate Theses and Dissertations

The field of power electronics is undergoing rapid advancement that is driven by the need for further electrification in all aspects of power generation and transmission, transportation, and consumer goods. Recent advances in wide bandgap (WBG) semiconductor technologies continue to push their adoption in systems with higher power densities and conversion efficiencies. However, the way in which the components of these systems are designed has not kept pace with the rapidly evolving landscape of their applications and often requires costly, manual design iteration. Therefore, new methods are needed to improve this design process. Packaging of power devices is a critical …

Physical And Stochiometric Controls On Nutrient Uptake And Ecosystem Respiration In Contrasting Sites, Jancoba K. Dorley

Civil Engineering ETDs

Meteorological, hydrological, and biogeochemical processes naturally control stream ecosystems. These processes define the frequency and distribution of precipitation and the supply and demand of solutes and particles to support aquatic food chains through space and time. Studies have also found that stream ecosystems are also controlled by anthropogenic activities, which occur on a much shorter timescale. These anthropogenic activities affect stream ecosystems' structure and function from local to planetary changes to the environment. It is essential for scientists and engineers to understand the relationships between naturally occurring processes and those created by human activities for a better interpretation of stream …

Additive Manufacturing Of Porous Tungsten Carbide Structural Electrode Components Using Robocasting, James Bevis

All Theses

Thanks to ideal mechanical and electrochemical properties, Tungsten Carbide (WC) shows excellent potential as a structural electrode material for multifunctional devices. These devices have applications in electric vehicles, for example, structural fuel cells and massless batteries. In such a context, structural WC electrodes will also benefit from porosity to decrease their weight and increase their surface area and chemical reactivity. Porous WC is a useful material for this field because of its high strength-to-weight ratio and electrical properties. However, current manufacturing methods can be expensive, complex, and limited, so the intent is to provide a more simplistic and sustainable method …

Broadening The Application Range Of Cell-Free Protein Expression Systems, Matthew Becker

All Theses

Centralized protein manufacturing platforms make the delivery of needed therapies to places with limited infrastructure almost impossible. Cell-free protein expression systems, systems that utilize protein production machinery extracted from cells, offer these communities a viable protein expression platform that is robust and easily deliverable to the place of need. Much work in cell-free system engineering looks to increase the hardiness of cell-free system (CFS) components, like the extract and reaction buffer, needed to carry transcription and translation of gene therapeutic targets forward. Freeze- and air-drying of extract, reaction buffer, or both with certain additives, like sugar molecules, has been proposed …

Dynamics Of Link Importance Across Flood Disaster Phases And Flood Impacts On Operation Of An Industry, Navin Bhatta

All Theses

Transportation damage and disruptions will become increasingly common as the frequency of floods increases due to climate change. Given the size and cost of the transportation network construction, communities' mitigation measures should be supported by evaluations that cover both normal and disaster management phases. This thesis examines the criticality of road segments in the normal, flood response, and recovery phases, considering the effects on emergency services, healthcare, industry, education, recreation, and transit and analyses that whether a flood disrupts the operational trips of a company in Anderson County, South Carolina. A 100-year event and a 500-year flood event provides context …

Quantifying Hurricane Effects On Housing: Evaluating Damage, Loss, And Shelter Demands Using Historical And Simulated Storm Tracks, Adish Deep Shakya

All Theses

This research introduces an advanced framework which employs parametric wind field models for peak wind speeds, and building fragility curves, loss functions, and demographic data to estimate for estimating housing damage and loss. The uninhabitable units immediate displaced households, short-term and long-term shelter need households are determined. with a particular focus on those eligible for FEMA assistance. The framework's validity is reinforced by a high correlation in the analysis of recent hurricane events between estimated numbers of displaced households and actual FEMA aid recipients, where FEMA aids about 20-60% of the predicted long-term displaced households. A novel application of the …

Analysis Of Cnn Performance Utilizing Jpeg Compressed Images Created On An Fpga, Timothy Shaughnessy

All Theses

JPEG (Joint Photographic Experts Group) was formed in 1986 to create a method to reduce image size primarily for ease of transfer on the Internet. Released to the public in 1992, JPEG compression is a form of lossless compression that has been a staple for compressing images. JPEG is the go-to image compressor because it provides high compression ratios while maintaining visual integrity for the human eye. Growing image sizes have made JPEG compression increasingly relevant. It is vital to keep up with growing data sizes for improved image handling performance on an edge device like a Field-Programmable Gate Array …

Advancements Of A Breast Tissue Marker And Localization System, Azrin Jamison

All Theses

Breast cancer has become the most prominent cancer worldwide in women. Annual mammograms are encouraged for women of high risk to increase early detection allowing for lumpectomies rather than mastectomies to occur. Prior to a lumpectomy, a biopsy must be taken to determine if the tissue is cancerous, and a breast cancer biopsy marker (BBM) is left in the region of possible cancerous tissue. Wire localization has been the gold standard for localizing these BBMs. However, due to the reported patient discomfort and logistical inefficiencies faced by healthcare providers (HCP), non-wire localization solutions have been recently developed. This study aims …

Laboratory Evaluation Of Remediation Alternatives For Groundwater At The Lane Street Superfund Site, Alyssa Costello

All Theses

At the Lane Street Groundwater Contamination Superfund site in Elkhart, Indiana, which includes industrial, commercial, and residential properties, a plume of contaminated groundwater was identified that requires remediation. The plume is chiefly composed of trichloroethylene (TCE) and has impacted residents’ drinking water. A microcosm study was performed to evaluate the potential of various treatment methods to remediate the Lane Street Superfund Site groundwater. The objectives of this microcosm study are to evaluate the potential for biostimulation, bioaugmentation, and abiotic degradation for implementation at this Site and to evaluate toxicity factors that have precluded natural degradation of the site contaminants. The …

Deep Reinforcement Learning Of Variable Impedance Control For Object-Picking Tasks, Akshit Lunia

All Theses

The increasing deployment of robots in industries with varying tasks has accelerated the development of various control frameworks, enabling robots to replace humans in repetitive, exhaustive, and hazardous jobs. One critical aspect is the robots' interaction with their environment, particularly in unknown object-picking tasks, which involve intricate object weight estimations and calculations when lifting objects. In this study, a unique control framework is proposed to modulate the force exerted by a manipulator for lifting an unknown object, eliminating the need for feedback from a force/torque sensor. The framework utilizes a variable impedance controller to generate the required force, and an …

Analytical And Experimental Studies To Support Codification Of Lightweight Grout For Masonry Design, Cooper Banks

All Theses

Lightweight (LW) aggregates have many potential benefits in masonry construction including minimizing mass, improving thermal performance, and reducing the potential for shrinkage cracking via internal curing. The current masonry design standard, TMS 402/602-22, permits lightweight aggregate in the production of concrete masonry units (CMU), but there has been insufficient testing of masonry assemblies to permit designing with LW grout. Shrestha et al. characterized LW grouts bond to reinforcement, shear strength, tension and shear pullout behavior of anchors and proposed possible reduction factors for design. Hiner characterized the flexural bond strength LW grouted masonry assemblies and proposed possible reduction factors for …

Analyzing A Software Based Lossy Compression Algorithm On An Fpga Platform, Tripp Herlong

All Theses

In HPC, the ability to generate data is outpacing our hardware capabilities of storing said data. This presents the need for compression so we can keep important data preserved without costly hardware upgrades or worrying about hardware speed limitations. Traditional forms of compression are software based, which presents a speed issue that can lead to bottlenecks when storing data.Scientific data lossy compression methods such as SZ enable a speedup on memory transfer by simplifying computation to minimize the essential data size. SZx is a lightweight version of the popular SZ floating point compressor that may benefit from hardware acceleration. This …

Layered Structure Protonic Ceramic Conductors Of The Form Ba5in2+Xal2zr1-Xo13-Δ, Nathan Cretegny

All Theses

In this work, the hexagonal perovskite of targeted composition Ba₅In_2+xAl₂Zr_1-xO₁₃ (x=0, 0.1, 0.2) was synthesized via a solid-state synthesis route to study the impact of oxygen vacancy concentration in layered hexagonal perovskites. Precursor oxides were mixed in stoichiometric proportions, calcined between 800-1200℃ and sintered at 1475℃. The sintered pellets were crushed into fine powders to investigate the chemistry and structure through X-ray diffraction, neutron diffraction, inductively coupled plasma mass spectrometry, and nuclear magnetic resonance. Dense pellets were used to study conductivity properties using electrochemical impedance spectroscopy.

The synthesis approach produced 100% …

Defining And Labeling Traversable Space In A Forested Environment, James Nguyen

All Theses

This thesis investigates the problem of identifying traversable terrain in outdoor conditions. We are motivated by research in recent years toward identifying drivable space for the purpose of developing autonomous vehicles. Our motivating application is similar but also different. We envision a “Hiker Helper” that assists humans with dismounted navigation in forested terrain. A common challenge in this type of environment is identifying a viable path for moving through terrain that is congested with trees, bushes, other flora, and natural obstacles that would make navigation difficult. We envision training an artificial intelligence (AI) model to automatically analyze images of this …

Hand Movement Analysis For Surgical Suturing Skill Assessment, Amir Mehdi Shayan

All Theses

To enhance patient safety, surgical education is increasingly incorporating simulation for formative skills assessment and training. However, many standardized assessment tools rely on human raters for performance assessment, which is resource-intensive and subjective. Simulators that provide automated and objective metrics from sensor data can address this limitation. This thesis presents an instrumented bench suturing simulator, patterned after the Clock Face (CF) radial suturing model from the Fundamentals of Vascular Surgery (FVS), for automated and objective assessment of open suturing skills by particularly focusing on biomechanical analysis of hand movements. For this research, 97 participants (35 attending surgeons and fellows, 32 …

A Transdisicplinary, Survivor-Centered Approach For Creating A System Dynamics Model Of Closed-Buyer Sex Trafficking Networks, Kemonte Yow

All Theses

One of the largest drivers of sex trafficking operations is the demand for commercial sex. To date, research from a quantitative side typically focuses on understanding how to best identify and remove victims from their trafficking situation and then support their healing and recovery. This may be because this is where data exists (in limited forms) to support quantitative modeling. This thesis broadens that scope to understand how demand for commercial sex impacts trafficking operations. In particular, this research implemented a transdisciplinary, survivor-centered approach to build a system dynamics model of a closed-buyer sex trafficking network, which is a network …

Development Of A Cost-Affordable Thin-Layer Chromatography Testing Kit For Falsified And Substandard Pharmaceuticals In Tanzania, Eleanor Hatcher

All Theses

A significant number of pharmaceuticals supplied to Tanzania are falsified or substandard. A majority of these inadequate pharmaceuticals are medications to treat life-threatening conditions. This problem not only causes mistrust in the healthcare system but also prolonged illness and potentially death for the patients. This calls for the need for the development of a cost-affordable testing kit for falsified and substandard pharmaceuticals in Tanzania. Thin-layer chromatography (TLC) was used as the testing method since it is inexpensive and requires a low skill level to complete. Malaria, human immunodeficiency virus, hypertension, tuberculosis, and diabetes are five of the most prevalent diseases …

Development And Evaluation Of An Arsenic Transport Model For The Maurice River Watershed, Christina Eddleman

All Theses

For many Superfund sites across the United States, arsenic is one of the most common contaminants of concern that must be cleaned up to protect human and environmental health. Past research and health studies have documented the harmful effects of inorganic arsenic on humans and the environment but selecting an appropriate remediation plan depends on several site-specific factors at each Superfund site. To assist in determining an appropriate remediation plan, sediment and contaminant transport models have been used to simulate the transport of arsenic and other contaminants of concern at contaminated sites to, e.g., make relative comparisons of the efficacy …

The Effect Of Football Facemask Design Variability On Dynamic Impact Performance And Quasi-Static Stiffness, Adam W. Smith

All Theses

This research addresses the role of facemasks in helmet systems, focusing on their dynamic impact performance and material properties. A total of 150 facemasks from 30 types and five helmets were tested both quasi-statically and dynamically. The facemasks were grouped by style and helmet type for comparison. Dynamic testing involved three different locations and two speeds, with data collected for maximum angular velocity and linear acceleration. Quasi-static stiffness, performed at two locations, was compared with collected dynamic results to determine the strength of relationship. A concussion metric, HARM, was calculated from collected data and compared across style groups.

Significant differences …

Amazon Fba Vs Fbm; A Strategic Approach To Determine Which Method Can Effectively Utilize Project Management Principles To Enhance Your Success As A New Amazon Seller., Tiffany Renee White

Theses and Dissertations

Navigating the complexities of a platform such as Amazon demands a strategic approach guided by project management principles. A comparative analysis of Fulfillment by Amazon (FBA) and Fulfillment by Merchant (FBM) methods were completed by focusing on how project management principles optimize product acquisition, supply chain management, and shipping methods for Amazon sellers. The objectives of this study included the identification of top product acquisition tools, the evaluation of inventory management software, assessing shipping methods, and determining the most effective fulfillment process for Amazon seller success. A mixed-methods approach was applied, involving an Amazon seller survey, literature review, data analysis, …

Utilization Of Confined Concrete In The Bottom Slab Of Double Composite Box Girder Bridges, Harry Craik

Theses and Dissertations

A mathematical model is proposed for the confinement of rectangular confined reinforced concrete elements under compression. The model was modified from existing models applied to rectangular confined concrete specimens. The present model applies to rectangular reinforced concrete cross-sections with a core aspect ratio of at least 2.0 and a high effective confinement index. The model applies to normal and high-strength concrete and incorporates the spacing of the transverse reinforcing hoops, the strength of the reinforcing bars, the reinforcing quantity, and the core aspect ratio of the section. The proposed model was verified against extensive experimental data, and there was a …

Microwave Imaging Technique For Breast Cancer Detection, Nure Alam Chowdhury

Theses and Dissertations

Breast cancer is a global problem, and it is inevitable to detect cancerous cells at early stages. In recent years, microwave imaging technology has been widely applied in biomedical applications for its non-ionizing radiation. In this study, we design a micro-strip patch antenna with an inverted T-type notch in the partial ground to detect tumor cells inside the human breast. The size of the current antenna is small enough (18 mm × 21 mm × 1.6 mm) to distribute around the breast phantom. The operating frequency has been observed from 6–14 GHz with a minimum return loss of −61.18 dB …

The Effect Of Extended Saltwater Absorption And Uv Cure On The Compressive Properties Of Msla 3d-Printed Photopolymer Resin Samples With Printing Variations, Suzanne Dixon

Theses and Dissertations

Liquid Crystal Display (LCD) 3D printers, also known as Masked Stereolithography Apparatus (MSLA), is a type of vat polymerization printing technique that cures liquid resin into a solid object. This technique is relatively new. Consequently, there is a shortage of detailed research on the impact of long-term environmental exposure on the MSLA-printed materials. The research within this document informs engineers and scientists of resin compressive properties after extended exposure to saltwater and ultraviolet (UV) light. Saltwater absorption of the material was analyzed at atmospheric pressure, 30-psi, 60-psi, and 90-psi; the samples reached saturation in saltwater after 56 days. The variation …

Denoising Diffusion Probabilistic Models Based Accelerated Mri, Alexander Francis Bugielski

Theses and Dissertations

Magnetic Resonance Imaging (MRI) is a cornerstone in obtaining intricate visualizations of anatomy and physiological processes within the human body. However, its extensive scan duration not only causes patient discomfort but also increases the likelihood of motion-induced artifacts in the images. To address such a challenge, this study investigates deep neural network models for reconstructing high-resolution MRI images from noisy and significantly undersampled data in a supervised learning manner. Specifically, it compares three models: a conventional U-Net, a self-attentive U-Net, and an innovative probabilistic diffusion model that builds upon the self-attentive U-Net architecture. These models are evaluated on their ability …

Fabrication And Performance Demonstration Of Compact Adsorption Heat Pump, Faraz Ege

Theses and Dissertations

Addressing global environmental concerns requires a shift to eco-friendly energy sources, particularly in cooling applications where traditional vapor-compression systems rely on harmful refrigerants and electricity. Thermally-driven cooling systems, like adsorption heat pumps, offer promise with their environmentally friendly refrigerants such as water and use of low-temperature heat sources, including solar energy or waste industrial heat. This dissertation undertakes a comprehensive investigation into the development and optimization of compact adsorption heat pumps, aiming to address the efficiency and environmental challenges inherent in conventional cooling systems.

This research begins by introducing a novel insertion coating technique for fabricating MIL-101 (Cr) adsorbent layers …

High-Fidelity 3d Reconstruction Of Space Bodies Using Machine Learning And Neural Radiance Fields, Timothy Jacob Huber

Theses and Dissertations

In the era of burgeoning space exploration, the growing population of spacecraft heightens the inevitability of collisions. While traditional imagery remains effective for damage assessment, its lack of 3D representation of the object necessitates more advanced approaches. This research delves into cutting-edge methodologies, with a primary focus on leveraging machine learning and computer vision technologies to enhance the precision and efficiency of damage assessment by taking imagery of a space body and creating a 3D model. The study extensively investigates TransMVSNet, a neural network code employing classical computer vision techniques such as multi-vision stereo (MVS) and depth maps. This approach …

Computational Fluid Dynamics Study Of Perforated Monopiles, Mary Kathryn Walker

Theses and Dissertations

Monopiles are used in the construction of offshore wind turbines and typically have a design life of 25 to 50 years. Over their lifecycle, monopiles are exposed to a corrosive saltwater environment, facilitating a galvanic oxidation process that quickly degrades the structure. This process can be mitigated by coating the monopile in a protective barrier and implementing cathodic protection techniques. Historically, monopile designers assumed the interior of the pile would be completely sealed and the galvanic corrosion process would eventually consume all the available oxygen, halting the reaction. However, penetrations made in the pile wall for conduit often leaked and …