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Full-Text Articles in Engineering

Sequential Optimization For Stressor-Informed Test Planning Through Integration Of Experimental And Simulated Data, Jacob Brecheisen May 2024

Sequential Optimization For Stressor-Informed Test Planning Through Integration Of Experimental And Simulated Data, Jacob Brecheisen

Data Science Undergraduate Honors Theses

This technical report details an innovative approach in reliability engineering aimed at maximizing system durability through a synergistic use of physical experimentation and computer-based modeling. Our methodology explores the efficient design and analysis of computer experiments and physical tests to facilitate accelerated reliability growth, while leveraging a sequential integration of data from these two distinct sources: costly physical experiments, characterized by random errors, and inexpensive computer simulations, marked by inherent systematic errors. The key innovation lies in the adoption of a closed-loop design and analysis method. This method begins by identifying a viable subset of important environmental stressors—such as temperature, …


Challenges That Impact The Development Of A Multi-Generational Low-Carbon Passive House In A Small City, Hanan Wehbi, Tahar Messadi May 2024

Challenges That Impact The Development Of A Multi-Generational Low-Carbon Passive House In A Small City, Hanan Wehbi, Tahar Messadi

Architecture Faculty Publications and Presentations

The impact of the building and construction sector on climate change is becoming more important and recognized. Multiple initiatives around the globe have been utilized to design and develop residential structures, aiming to reduce energy consumption and carbon emissions; yet, there are several barriers to effective construction processes. This research outlines the gaps and barriers encountered by key stakeholders that were engaged during the preconstruction phase of a three-story multi-generational low-impact Passive House in Fayetteville, Arkansas. Through direct observation and open-ended interviews, the primary data are collected, and secondary data from a comprehensive literature review are detailed to capture the …


The Analysis Of Mechanical Exfoliation Of Graphene For Various Fabrication And Automation Techniques, Lance Yarbrough May 2024

The Analysis Of Mechanical Exfoliation Of Graphene For Various Fabrication And Automation Techniques, Lance Yarbrough

Physics Undergraduate Honors Theses

Mechanical Exfoliation


Micro-Mechanical Characterization Of Uhpc Stiffness Mechanisms: Towards A Better Understanding Of Concrete Elastic Modulus, Charissa N. Puttbach May 2024

Micro-Mechanical Characterization Of Uhpc Stiffness Mechanisms: Towards A Better Understanding Of Concrete Elastic Modulus, Charissa N. Puttbach

Graduate Theses and Dissertations

Current design code equations for estimating the elastic modulus of specialty concretes like ultra-high performance concrete are not all suitable. Developing empirical curves from exhaustive experimental testing is challenging for concretes that may have high levels of cement replacement with mineral admixtures and fibers at varying volume contents. As such, an alternative approach is taken that seeks to understand the constituent microscale stiffness mechanisms and relate the results to the macroscale. Micropillars are fabricated on several cement paste phases using a focused ion beam. A modified pico-indenter is used to determine the linear and non-linear behavior under micro-compression loading. Micropillar …


Providing A Statistical Analysis Framework For Agencies To Analyze The Parameters Influencing The Rutting And Cracking Performance Of Asphalt Mixtures, Mohammad Tahir Ansari May 2024

Providing A Statistical Analysis Framework For Agencies To Analyze The Parameters Influencing The Rutting And Cracking Performance Of Asphalt Mixtures, Mohammad Tahir Ansari

Graduate Theses and Dissertations

Many state agencies recognize that their current asphalt mixtures are susceptible to cracking and poor durability. Some agencies are adjusting their mix design procedures to increase the asphalt binder content, while others are moving toward a balanced mix design (BMD) to try and address both cracking and rutting. However, there is uncertainty on what asphalt mixture properties can impact cracking and rutting. This research explores the IDEAL-CT and APA data from two years of mix designs collected by ARDOT. To understand which asphalt mixture properties impact cracking and rutting in the field, Pearson correlation (PCM), Spearman rank correlation (SCM) and …


Proctor And Harvard Miniature Compaction Energy Comparison, Julia Loshelder May 2024

Proctor And Harvard Miniature Compaction Energy Comparison, Julia Loshelder

Graduate Theses and Dissertations

Compaction with the Harvard Miniature Compaction Apparatus (HMCA) was investigated to develop a method that can be used in place of typical Proctor compaction. Advantages for compaction with the HMCA include the need for less soil for testing and less preparation time. To investigate the potential for HMCA as a replacement, soil specimens were compacted with both the Proctor and HMCA methodologies at equivalent energies. For this testing, the testing included modified energy (56,250 ft-lbf/ft3 [2693 kN-m/m3]), standard energy (12,375 ft-lbf/ft3 [593 kN-m/m3]), and reduced energy (6188 ft-lbf/ft3 [296 kN-m/m3]). Because …


Addressing Data Limitations Of Commercial Waterways Via Machine Learning And Stochastic Optimization, Sanjeev Bhurtyal May 2024

Addressing Data Limitations Of Commercial Waterways Via Machine Learning And Stochastic Optimization, Sanjeev Bhurtyal

Graduate Theses and Dissertations

Freight transportation is a crucial component of the US economy, with truck, rail, and water contributing significantly to the Gross Domestic Product (GDP). However, challenges arise in maintaining infrastructure capacity to accommodate the growing tonnage and value of freight transportation. Waterways offer high efficiency and environmental friendliness, with the capacity to transport substantial cargo volumes. Utilizing waterways can alleviate bottlenecks in landside transportation, accommodating the rising tonnage of commodity flow in the US. Despite the advantages of waterway transportation, the data limitations hinder informed decision-making regarding port operation and infrastructure investment. The lack of granularity and timeliness in available data …


Cyclic Testing Of A Skewed Special Moment Frame Rbs Connection Having A Composite Concrete Slab, Adam Neil Kirchner May 2024

Cyclic Testing Of A Skewed Special Moment Frame Rbs Connection Having A Composite Concrete Slab, Adam Neil Kirchner

Graduate Theses and Dissertations

Special moment frames (SMFs) having reduced beam section (RBS) connections are commonly used in high seismic areas as they resist lateral forces while preserving critical welded connection regions. RBS SMFs provide brace-free, unobstructed frame options which can be favorable for architectural purposes. However, when building designs require non-rectangular framing, laterally skewed connections may be needed. Current design provisions for SMF connections provide only limited commentary on such non-orthogonal connections as limited research exists documenting skewed frame behavior. This study experimentally evaluates the cyclic behavior of a full-scale double-sided skewed SMF RBS specimen having a composite concrete slab. During the imposed …


Dna/Carbon Nanotube Hybrid Structure And Their Translocation Through A Nanochannel, Daniel Christoffel Viljoen May 2024

Dna/Carbon Nanotube Hybrid Structure And Their Translocation Through A Nanochannel, Daniel Christoffel Viljoen

Graduate Theses and Dissertations

DNA sequencing is of major importance as it is used in fields such as species differentiation, personalized medicine and food safety. Currently sequencing by synthesis is the most popular commercial method of sequencing DNA while Oxford nanopore’s protein based nanopores are the only portable commercial method. Current nanopore based devices have three main issues: Spacial resolution, translocation rate versus sensor strength and dealing with the persistence length of ssDNA. This thesis contributes to ongoing research that aims to create a nanochannel with integrated sensor based sequencing device. The project has two main objectives. The first objective is to improve the …


Use Of Bcsa Cement In Soil-Cement Mixtures As A Rapid Flood Repair Technique, Mariel Mayori Rivero May 2024

Use Of Bcsa Cement In Soil-Cement Mixtures As A Rapid Flood Repair Technique, Mariel Mayori Rivero

Graduate Theses and Dissertations

The research discusses the vulnerable condition of hydraulic structures, specially dams and levees located in the United States, structures that are often times made of earthfill material and that have been greatly impacted by recent flood events. The need for a rapid setting material for active flood fighting efforts is inarguable, in order to mitigate collateral expenses caused by the often long closure times when repair is taking place, especially when dewatering is necessary. Therefore, this research tested different proportions of cement in soil-cement mixtures at varying moisture contents with the interest of evaluating the performance of the soil-cement when …


Investigating The Presence Of Patented In Vitro Models For Cancer-Nerve Crosstalk Methods, Christoff Hauptmann May 2024

Investigating The Presence Of Patented In Vitro Models For Cancer-Nerve Crosstalk Methods, Christoff Hauptmann

Biomedical Engineering Undergraduate Honors Theses

The purpose of this research project is to investigate the presence of patented in vitro models for perineural invasion (PNI) and tumor innervation, the two most prominent modes of cancer-nerve crosstalk that play an active role in cancer initiation and progression. PNI occurs through a positive feedback loop in which cancer cells invade passive nerves to metastasize. Tumor innervation is the process where tumor cells attract nearby nerves to the tumor microenvironment (TME) for tumor growth and metastasis. These crosstalk paths have been established for many types of cancer and result in poor patient prognosis. Recently, in vitro models have …


Evaluation Of The Efficiency Of Muscle-Specific Promoters To Express Non-Endogenous Proteins In Skeletal Muscle, Gabrielle Bulliard, Made Harumi Padmaswari, Christopher E. Nelson May 2024

Evaluation Of The Efficiency Of Muscle-Specific Promoters To Express Non-Endogenous Proteins In Skeletal Muscle, Gabrielle Bulliard, Made Harumi Padmaswari, Christopher E. Nelson

Biomedical Engineering Undergraduate Honors Theses

Gene therapies are emerging as powerful tools for treating genetic diseases and cancers, offering the potential for a permanent cure. Hemophilia B, affecting approximately 6,000 men in the U.S., results from a deficiency in coagulation factor IX protein (FIX), which is crucial for blood clotting. A substantial portion of patients, over 40%, suffer from severe hemophilia B, experiencing spontaneous, prolonged bleeding. Current prophylactic treatments involve frequent coagulation factor infusions, yet a curative approach would alleviate this burden. Gene editing technologies like CRISPR-Cas systems show promise for correcting genetic mutations, but the diverse nature of factor IX gene (F9) …


Open-Source Optimization For Green Last Mile Delivery And Other Applications, John Sooter May 2024

Open-Source Optimization For Green Last Mile Delivery And Other Applications, John Sooter

Industrial Engineering Undergraduate Honors Theses

Solving combinatorial optimization problems at scale and of sufficiently interesting context has historically required commercial solvers and access to proprietary company data. The development of performant open-source mathematical programming software and crowdsourced datasets has created an opportunity for individuals and enterprises alike to consider alternative solutions to problems with social and personal implications. This honors thesis represents a summary of my undergraduate research work, an application of optimization to three distinct problems connected to these developments. First, we present an optimization study of a last mile delivery system that shows optimization for energy consumption can generate vehicleindependent fuel savings at …


Investigating The Integration Of Demand Distribution Modeling In Supply Chain Simulation, Marshal Ray May 2024

Investigating The Integration Of Demand Distribution Modeling In Supply Chain Simulation, Marshal Ray

Industrial Engineering Undergraduate Honors Theses

This research presents a methodology for modeling the amount of demand and the time intervals between demands within a complex supply chain simulation program. The research outlines the approach, incorporating factor analysis and consolidation techniques, with a focus on using Random Forest modeling for factor importance identification. The results section covers demand quantity modeling utilizing both continuous and discrete empirical approaches, accompanied by considerations for outlier and overall distributions. While using these modeling techniques, P-P plots and KS-Statistics were employed to assess the goodness of fit, as a way to make recommendations for these models. The time between demand modeling …


Transcriptomic Profiling Of Engineered Human Gene Integration In The Mouse Genome Following In Vitro Gene Editing, Ethan Potts, Made Harumi Padmaswari, Christopher Nelson May 2024

Transcriptomic Profiling Of Engineered Human Gene Integration In The Mouse Genome Following In Vitro Gene Editing, Ethan Potts, Made Harumi Padmaswari, Christopher Nelson

Biomedical Engineering Undergraduate Honors Theses

Gene replacement is a promising method of therapy for genetic diseases. However, safety and efficacy are areas that need more research. This experiment aims to use RNA sequencing and bioinformatic techniques to provide answers to these questions and provide direction to future studies to develop a gene replacement therapeutic. C2C12 mouse myoblast cells were transfected with a vector containing a CRISPR-Cas9 system and the Human Factor IX (hF9) gene in order to hijack target genes and integrate the hF9 gene. The two target genes, myoglobin (Mb) and creatine kinase (Ckm), were chosen for their high rate of expression and low …


Real-Time Measurements From Wearable Sensors To Enhance Stability On Uneven Terrain, Sophie Copelin May 2024

Real-Time Measurements From Wearable Sensors To Enhance Stability On Uneven Terrain, Sophie Copelin

Biomedical Engineering Undergraduate Honors Theses

The presented thesis is a study of sensation associated with inversion/eversion movement about the anterior/posterior axis. The long-term goal is to create a system that provides feedback to a prosthesis user, so their chances of falling is decreased. This feedback system would use wearable sensors to detect certain angles, so that sensory feedback could be provided. The study aimed to determine if Xsens Movella DOT sensors could be used in a system like this, so the accuracy of the Xsens Movella DOT sensors was assessed and the difference in angles that could be determined by them when compared to that …


A Comprehensive Analysis Of Training Induced Heat-Related Injuries At Fort Moore, Anthony Beger May 2024

A Comprehensive Analysis Of Training Induced Heat-Related Injuries At Fort Moore, Anthony Beger

Data Science Undergraduate Honors Theses

Heat related injuries are a significant problem for the United States Armed Forces. There were over 11,000 confirmed cases of heat-related illnesses that were diagnosed at more than 230 military installations from 2018-2022. These injuries are primarily due to hyperthermia (i.e., abnormally high body temperature) resulting from extreme environmental temperatures, high humidity, medications, or excessive physical work or exercise. Fort Moore has the most heat related injuries of any installation in the U.S. Department of Defense since it is home to one of the largest U. S. Army training posts with most training involving intensive outdoor activity in high heat …


Comparing North American Professional Sports League Season Formats Using Monte Carlo Simulation, Lathan Gregg May 2024

Comparing North American Professional Sports League Season Formats Using Monte Carlo Simulation, Lathan Gregg

Industrial Engineering Undergraduate Honors Theses

Each NFL, NBA, and MLB season consists of a regular season, in which teams play a set number of scheduled games and a playoff, in which qualifying teams compete for a championship. At the conclusion of each season, teams are ranked based on their performance throughout the season. This study aims to investigate the ability of each league's season format to accurately rank teams using Monte Carlo simulation. Matches between two teams are simulated by using the team’s assigned strength ranks to calculate a winning probability for each team. The winning probabilities are simulated with different skill values, dictating how …


Using Convolutional Neural Networks For Autonomous Drone Navigation, Joshua Jowers May 2024

Using Convolutional Neural Networks For Autonomous Drone Navigation, Joshua Jowers

Industrial Engineering Undergraduate Honors Theses

Unmanned Aerial Vehicles (UAVs), more commonly known as drones, serve various purposes, notably in military applications. Consequently, there arises a need for navigation methods impervious to intercepted signals [1]. Previous research has explored numerous solutions, including machine learning. This paper delves into a specific machine learning approach employing a Convolutional Neural Network (CNN) to discern image locations [2]. It elucidates the conversion of a CNN model between two machine learning libraries and presents results from multiple experiments examining parameters and factors influencing the approach's efficacy. These experiments encompass testing different data sources, image quantities, and processing pipelines to gauge their …


Challenges For Room Temperature Operation Of Electrically Pumped Gesn Lasers, A. R. Ellis, D. A. Duffy, I. P. Marko, S. Acharya, W. Du, S. Q-. Yu, S. J. Sweeney May 2024

Challenges For Room Temperature Operation Of Electrically Pumped Gesn Lasers, A. R. Ellis, D. A. Duffy, I. P. Marko, S. Acharya, W. Du, S. Q-. Yu, S. J. Sweeney

Electrical Engineering and Computer Science Faculty Publications and Presentations

Recent demonstrations of room-temperature lasing in optically pumped GeSn show promise for future CMOS compatible lasers for Si-photonics applications. However, challenges remain for electrically pumped devices. Investigation of the processes that limit device performance is therefore vital in aiding the production of future commercial devices. In this work, a combined experimental and modelling approach is utilised to explore the dominant loss processes in current devices. By manipulating the band structure of functioning devices using high hydrostatic pressure techniques at low temperature, the dominant carrier recombination pathways are identified. This reveals that 93 ± 5% of the threshold current is attributable …


The Epitaxial Growth Of Ge And Gesn Semiconductor Thin Films On C-Plane Sapphire, Emmanuel Wangila, Calbi Gunder, Petro M. Lytvyn, Mohammad Zamani-Alavijeh, Fernando Maia De Oliveira, Serhii Kryvyi, Hryhorii Stanchu, Aida Sheibani, Yuriy I. Mazur, Shui-Qing Yu, Gregory J. Salamo May 2024

The Epitaxial Growth Of Ge And Gesn Semiconductor Thin Films On C-Plane Sapphire, Emmanuel Wangila, Calbi Gunder, Petro M. Lytvyn, Mohammad Zamani-Alavijeh, Fernando Maia De Oliveira, Serhii Kryvyi, Hryhorii Stanchu, Aida Sheibani, Yuriy I. Mazur, Shui-Qing Yu, Gregory J. Salamo

Physics Faculty Publications and Presentations

Ge1−xSnx growth on a new sapphire platform has been demonstrated. This involved the growth of GeSn on Ge/GaAs layers using the algorithm developed. The resultant growths of Ge on GaAs/AlAs/sapphire and Ge1−xSnx on Ge/GaAs/AlAs/sapphire were investigated by in situ and ex situ characterization techniques to ascertain the surface morphology, crystal structure, and quality. The growth mode of Ge on GaAs was predominantly two-dimensional (2D), which signifies a layer-by-layer deposition, contributing to enhanced crystal quality in the Ge/GaAs system. The growth of Ge1−xSnx with 10% Sn on a graded profile for 30 …


Spin Disorder Control Of Topological Spin Texture, Hongrui Zhang, Yu-Tsun Shao, Xiang Chen, Binhua Zhang, Tianye Wang, Fanhao Meng, Kun Xu, Peter Meisenheimer, Xianzhe Chen, Xiaoxi Huang, Piush Behera, Sajid Husain, Tiancong Zhu, Hao Pan, Yanli Jia, Nick Settineri, Nathan Giles-Donovan, Zehao He, Andreas Scholl, Alpha N'Diaye, Padraic Shafer, Archana Raja, Changsong Xu, Lane W. Martin, Michael F. Crommie, Jie Yao, Ziqiang Qiu, Arun Majumdar, Laurent Bellaiche, David A. Muller, Robert J. Birgeneau, Ramamoorthy Ramesh May 2024

Spin Disorder Control Of Topological Spin Texture, Hongrui Zhang, Yu-Tsun Shao, Xiang Chen, Binhua Zhang, Tianye Wang, Fanhao Meng, Kun Xu, Peter Meisenheimer, Xianzhe Chen, Xiaoxi Huang, Piush Behera, Sajid Husain, Tiancong Zhu, Hao Pan, Yanli Jia, Nick Settineri, Nathan Giles-Donovan, Zehao He, Andreas Scholl, Alpha N'Diaye, Padraic Shafer, Archana Raja, Changsong Xu, Lane W. Martin, Michael F. Crommie, Jie Yao, Ziqiang Qiu, Arun Majumdar, Laurent Bellaiche, David A. Muller, Robert J. Birgeneau, Ramamoorthy Ramesh

Physics Faculty Publications and Presentations

Stabilization of topological spin textures in layered magnets has the potential to drive the development of advanced low-dimensional spintronics devices. However, achieving reliable and flexible manipulation of the topological spin textures beyond skyrmion in a two-dimensional magnet system remains challenging. Here, we demonstrate the introduction of magnetic iron atoms between the van der Waals gap of a layered magnet, Fe3GaTe2, to modify local anisotropic magnetic interactions. Consequently, we present direct observations of the order-disorder skyrmion lattices transition. In addition, non-trivial topological solitons, such as skyrmioniums and skyrmion bags, are realized at room temperature. Our work highlights …


Algorithm-Based Linearly Graded Compositions Of Gesn On Gaas (001) Via Molecular Beam Epitaxy, Calbi Gunder, Mohammad Zamani-Alavijeh, Emmanuel Wangila, Fernando Maia De Oliveira, Aida Sheibani, Serhii Kryvyi, Paul C. Attwood, Yuriy I. Mazur, Shui-Qing Yu, Gregory J. Salamo May 2024

Algorithm-Based Linearly Graded Compositions Of Gesn On Gaas (001) Via Molecular Beam Epitaxy, Calbi Gunder, Mohammad Zamani-Alavijeh, Emmanuel Wangila, Fernando Maia De Oliveira, Aida Sheibani, Serhii Kryvyi, Paul C. Attwood, Yuriy I. Mazur, Shui-Qing Yu, Gregory J. Salamo

Physics Faculty Publications and Presentations

The growth of high-composition GeSn films in the future will likely be guided by algorithms. In this study, we show how a logarithmic-based algorithm can be used to obtain high-quality GeSn compositions up to 16% on GaAs (001) substrates via molecular beam epitaxy. Herein, we use composition targeting and logarithmic Sn cell temperature control to achieve linearly graded pseudomorph Ge1−xSnx compositions up to 10% before partial relaxation of the structure and a continued gradient up to 16% GeSn. In this report, we use X-ray diffraction, simulation, secondary ion mass spectrometry, and atomic force microscopy to analyze and …


Detection Of Hypoxia Via Rgb Imaging, Nathania Nischal May 2024

Detection Of Hypoxia Via Rgb Imaging, Nathania Nischal

Biomedical Engineering Undergraduate Honors Theses

Colorectal cancer is a common form of cancer, and is heavily researched in murine models. Colonoscopies are often performed in clinical settings to assess the health of the colon, as well as locate and assess the severity of tumors in a non-invasive way. As the quality of the images is dependent on the colonic environment and the light available, it is important to ensure the accuracy of the images via a normalization algorithm. The RGB images procured from these colonoscopies have great potential as a diagnostic tool for physicians, as varying scales of discoloration is common in hypoxic tissue. While …


Dorsal Root Ganglia Neurite Outgrowth Following Traumatic Spinal Cord Injury Repair: A Review, Adrienne Vaughan May 2024

Dorsal Root Ganglia Neurite Outgrowth Following Traumatic Spinal Cord Injury Repair: A Review, Adrienne Vaughan

Biomedical Engineering Undergraduate Honors Theses

Traumatic spinal cord injury (tSCI) can cause partial sensorimotor deficiency or total dysfunction, rendering patients unable to perform necessary tasks and dramatically decreasing their quality of life. tSCI is a very prevalent issue. In the United States alone, there are approximately 54 new cases of SCI per one million people each year, or 18,000 new cases annually. tSCI creates a lesion gap filled with axon-inhibiting fibrotic scar tissue. Comprehensive functional recovery following traumatic spinal cord injury (tSCI) requires axonal regeneration across wound site lesions. Dorsal root ganglia (DRG) neurite outgrowth is often evaluated in PNI therapeutic research since it can …


Computational Predictions Of Heart Failure Drug Effects On Cardiac Fibrosis, Aaron Gardner May 2024

Computational Predictions Of Heart Failure Drug Effects On Cardiac Fibrosis, Aaron Gardner

Chemical Engineering Undergraduate Honors Theses

The extracellular matrix is a complex system surrounding cells that is crucial to all of the cardiovascular system’s functions. Fibrosis is an excessive accumulation (scarring) of the extracellular matrix. Fibrosis is typically a negative event, and the scarring must be reduced in the heart in order to maintain its functionality. Due to this, simulations are run using the software “Netflux” in order to determine the effects of different heart failure drugs on cardiac fibrosis. The drugs that were simulated were an ACE Inhibitor, BAR Beta Blocker, ARB Blocker, and Entresto. These drugs were simulated over 50 hours at three different …


Optimization Of Collagen And Cell Concentrations For Engineered Tissues, Avery Fiser May 2024

Optimization Of Collagen And Cell Concentrations For Engineered Tissues, Avery Fiser

Chemical Engineering Undergraduate Honors Theses

Improvements regarding the drug discovery process are necessary due to less than 1% of drugs making it from the initial discovery phase to patient treatment in clinics. One method of enhancing this process involves improving the relevance and dependability of in vitro testbeds utilized during pre-clinical testing. Improvement along these factors can provide a more relevant view for eventual drug behavior in patients. This additional relevance can allow for a reduced timeline in drug development for improving patient care. A consistent and morphologically sound baseline engineered tissue is vital to the creation of successful experimental models. Parameters such as cell …


Encapsulated 2d Materials And The Potential For 1d Electrical Contacts, Sarah Wittenburg May 2024

Encapsulated 2d Materials And The Potential For 1d Electrical Contacts, Sarah Wittenburg

Physics Undergraduate Honors Theses

The utilization of two-dimensional materials and heterostructures, particularly graphene and hexagonal boron nitride, have garnered significant attention in the realm of nanoelectronics due to their unique properties and versatile functionalities. This study focuses on the synthesis and fabrication processes of monolayer graphene encapsulated between layers of hBN, aiming to explore the potential of these heterostructures for various electronic applications. The encapsulation of graphene within hBN layers not only enhances device performance but also shields graphene from environmental contaminants, ensuring long-term stability. Experimental techniques, including mechanical exfoliation and stamp-assisted transfer, are employed to construct three-layer stacks comprising hBN-graphene-hBN. The fabrication process …


Flow Characterization With Acoustic Emission Sensing, Jackson Marsh May 2024

Flow Characterization With Acoustic Emission Sensing, Jackson Marsh

Mechanical Engineering Undergraduate Honors Theses

Acoustic emissions (AE) allow for non-intrusive sensing into many types of systems. In systems where there is flow of some type, AE is very useful as these types of systems can be characterized in many ways from the collisions or creation of the flow. Correctly setting up the AE system is extremely important. Failure to do so results in imprecision and inaccurate data being collected. Because of this synchronization techniques, sensor configurations, and data acquisition systems must all align. This can be done with off-the-shelf, commercial systems, but this does not allow for customization and the ability to tailor the …


A 10 Kv Sic Mosfet Power Module With Optimized System Interface And Electric Field Distribution, Xiaoling Li May 2024

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 …