Digital Commons Network^™

Validating An Electronics Cooler Experiment And Optimizing Its Performance Using Ansys Icepak, Daniel V. Curl

Mechanical Engineering Undergraduate Honors Theses

Researchers at the University of Arkansas' Mechanical and Electrical Engineering Research Departments have designed and built a cold plate and substrate design for a 10 kV SiC MOSFET power module. Many variables define the design of the cold plate and substrate system and have quantifiable effects on the device’s performance. These variables include but are not limited to geometry and material selection of the fins and substrate. Manufacturing many test designs, running experiments, and comparing their performance is a time-consuming and expensive design optimization method that may be effective for some low-cost applications. Still, simulation is often a more cost-effective …

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 …

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 …

Automation Programming For Uhv-Cvd Growth Of Group Iv Materials, William Hay

Electrical Engineering and Computer Science Undergraduate Honors Theses

The automation programming of a UHV-CVD reactor for group IV materials was performed. The reactor was programmed to perform all the necessary functions for a Germanium (Ge) growth with little response from the user. The overall goal was to fix an Argon purge program to clean out the process chamber of gases and create an Excel output program to ease any work on the user. There were also general fixes and address name changes that occurred throughout the program. Then, a one step and two step growth of a Ge material was formed in a UHV-CVD reaction for analysis. Germanium …

Defect Characterization Of Sic Schottky Barrier Diode Using Deep Level Transient Spectroscopy, Zachary I. Mccoy

Electrical Engineering and Computer Science Undergraduate Honors Theses

The aim of this project is to use deep level transient spectroscopy (DLTS) to energetically evaluate defects by using the carrier concentration dependence on temperature and where these carriers may experience deviation from standard predictions. These defects become apparent through multiple C-V measurements that are swept through a temperature range. By analyzing trends with respect to temperature, the defects can be energetically “located,” and thus identified. This identification can help streamline semiconductor material manufacturing/growth because DLTS identifies potential defect causes by providing data to characterize semiconductor mid-band defects. DLTS can assess nearly all parameters associated with traps/defects including density, thermal …

Design, Simulation, And Testing Of Planar Transformer For Smart Green Power Node (Sgpn) Isolation Using Ansys, Brooke Scott

Electrical Engineering and Computer Science Undergraduate Honors Theses

The goal of this project was to design and simulate a small, high-frequency, planar, ferrite-core transformer which can be used in a variety of applications, the most relevant of which is photovoltaic (PV) converter systems, which often require bulky transformers to function properly. The current research involved several processes: (1) Understanding and designing a tutorial for the use of Ansys software to aid in the efficient development and modeling of transformers, (2) designing and simulating a planar transformer in Ansys to be used in a solar converter, specifically the Smart Green Power Node (SGPN), and (3) testing the planar transformer …

Investigation And Characterization Of Silicon Carbide Power Mosfets, Vincent Hassman

Electrical Engineering and Computer Science Undergraduate Honors Theses

As engineers constantly seek to make solar power systems smaller, cheaper, and more efficient, technological enhancements in the electronics that run them are required. One of the most fundamental electronic components of any solar system is the inverter, which takes DC current from the solar cell and turns it into AC current that is supported by the grid. This is done with metal oxide semiconductor field effect transistors (MOSFETs). Through more advanced MOSFET technology, inverters can switch at a higher frequency, increasing efficiency and reducing size and cost.

MOSFET performance can be enhanced by swapping the traditional silicon substrate with …

Emerging Applications On Reconfigurable Computing Platforms, Zhenyu Xu

All Dissertations

Security and high-performance computing have become two of the most critical demands in modern technology. The increasing complexity of digital systems, the need for real-time processing, and the emergence of sophisticated cyber threats require computing solutions that balance computational power with adaptability and security. Reconfigurable computing platforms, particularly Field-Programmable Gate Arrays (FPGAs), offer a promising solution to these challenges by combining flexibility with hardware acceleration. Many new applications have emerged with the developing of reconfigurable platforms.

FPGAs can be utilized in two primary directions: as control and high-precision measurement units for security-sensitive applications, and as accelerators capable of outperforming GPUs …

Hybrid Fea And Meta-Modeling For De Optimization Of A Highly Saturated Spoke Ipm, Oluwaseun A. Badewa, Marcelo Silva, Rosemary E. Alden, Pedram Asef, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

This paper introduces a novel approach for high performance electric motor design that combines machine learning (ML)-based meta-modeling with a differential evolution (DE) optimization algorithm. The method leverages finite element analysis (FEA) results to train the ML meta-model, enabling efficient design optimization for high-power density cored machines, such as spoke interior permanent magnet motors (IPM), which exhibit complex nonlinearities and saturation effects. This hybrid ML-DE framework seeks to provide an alternative for physics-based electric motor design and optimization, offering significant reductions in computational effort while maintaining accuracy. The meta-model’s accuracy in capturing the nonlinear relationships between design parameters, core losses, …

Modality Distillation Using A Sam-Guided Multimodal Teacher For Unimodal Wildfire Segmentation And Temperature Prediction, Michael N. Marinaccio

All Theses

Wildfires are one of the world’s most devastating natural disasters that affect the environment, communities, and more critically, humans that live in and around those communities. Due to the threat of large-scale destruction in landscapes and human inhabited areas, it has become increasingly more important to develop wildfire detection, management, and suppression strategies to mitigate and prevent these negative outcomes. Wildfire research encompasses many different areas. Most notably, the development of communication, navigation, remote sensing, and monitoring systems. In wildfire monitoring, limitations discovered in-ground and satellite observation have shifted the focus toward Unmanned Aerial Vehicle (UAV) based wildfire research, which …

Analog Low Dropout Regulator Design Within A 12nm Finfet Node, Harshdeep Singh

Graduate Theses and Dissertations

Modern ICs require the use of multiple voltage regulators to regulate power, this creates the need for analog low dropout regulator (LDO) designs in more advanced nodes such as for the 12nm FinFET process. Analog design is particularly challenging in FinFET processes due to a variety of factors, such as quantized parameters, large parasitic values and length of diffusion effects. An analog LDO was chosen for its improved power supply rejection ratio (PSRR) over digital and hybrid approach which is a key metric for voltage sensitive applications. The LDO was designed through an iterative approach to address the difficulty of …

Design Considerations Of A Gpu, Nicholas M. Devilliers

Electrical Engineering and Computer Science Undergraduate Honors Theses

With the current era of AI technology, the era of single instruction multiple data has become an increasingly viable solution to accelerate training. The problem is that while software to use GPUs and other hardware accelerators, designing GPUs and ASIC devices has become increasingly more expensive and there aren’t great examples of generic GPUs that anyone can use and modify. In this thesis, there are four design considerations that will be discussed and how they affect the result of a generic GPU. The four considerations that were talked about in the thesis are, word width, arithmetic type, number of stages, …

Finding Groundwater With Electricity: Research And Testing Of An Electro-Resistive Ground-Surveying Device For Use In Well-Drilling Applications, Samuel L. Heath

Senior Honors Theses

A custom-built electro-resistive water detection device is tested under various conditions to evaluate its overall performance and sensitivity to changing variables. The tests, designed to assess accuracy and precision, revealed that the prototype exhibits high reliability (~ 99%) for both Schlumberger and Wenner arrays across different electrode spacings and soil conditions. Moreover, the measured resistivity values from the soil tests aligned with established literature ranges for each soil type. The device also showed the ability to consistently detect changes in soil water content by producing measurable variations in resistivity. At a total cost of $181, this prototype can serve as …

Physics Embedded Neural Network: A Novel Data-Free Numerical Method For Solving Computational Physics Problems, Pawan Gaire

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

A novel approach for solving partial differential equations (PDEs) using neural networks for scientific computing is introduced. The proposed approach, referred to as physics-embedded neural network (PENN), features a unique architecture that incorporates the PDE and boundary conditions information directly within the final fully-connected layer of the feed-forward neural network (NN). The key aspect of PENN is the parallel numerical embedding of a differential equation associated with physical problems within the activation function of the network’s final layer. This integration leads to a new class of computational solvers competitive with classical methods like the Finite Element Method (FEM) and capable …

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.

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 …

Spin Coater Design With Pid Algorithm Using Polynomial Regression Approach And Bias Tuning For Tio2 Deposition Process, Geo Surya Andika, Nofrijon Sofyan, Donanta Dhaneswara, Akhmad Herman Yuwono

Journal of Materials Exploration and Findings

The thin-film deposition technique using spin coating offers a cost-effective alternative to Chemical Vapor Deposition (CVD) and Physical Vapor Deposition (PVD). The spin-coating process requires precise control of the motor drive system to ensure that the rotational speed, measured in rotations per minute (RPM), aligns with the set point and remains stable. This study presents the design and development of a spin coater prototype to achieve uniform thin-film deposition. The control method employed utilizes a Proportional-Integral-Derivative (PID) algorithm, incorporating a polynomial approach with bias tuning. The PID control was chosen to achieve stable operation in a non-linear system. The performance …

Design Of A Novel Low-Cost Hybrid V-Shape Spoke-Type Ferrite Ipm-Synrm For Ev Traction Using Fem Software, Kenghao Cai

Master's Theses

This paper presents a hybrid V-shape spoke type ferrite Interior Permanent Magnet Synchronous Reluctance Machine (PMA-SynRM) for electric vehicle traction application. Ferrite or ceramic IPM-SynRMs compared to Neodymium (NdFeB) based IPM-SynRMs typically have lower torque, power density, and efficiency overall. Motivated by rising costs and international policies making it increasingly more challenging to obtain rare-earth metals, alternatives should be explored. With the help of finite element method (FEM) software, Ansys Maxwell, this study probes into a novel three-phase ferrite-only hybrid Spoke-type V-shaped IPM-SynRM using Tesla Model 3's neodymium powered V-shape interior permanent magnet machine as a benchmark. The proposed motor …

Optimizing And Training An Svm-Based Breast Cancer Tumor Classifier, Kevin Lopatka

Master's Theses

With advancements in technology, turning to machine learning has become a popular choice for aiding clinicians in the diagnoses of breast cancer malignancies. While the neural networking approach has been vetted thoroughly, this work aims to take advantage of traditional machine learning techniques; mainly support vector machine learning and the optimizing of feature extraction. The discrete-wavelet transform is used in the feature extraction stage of machine learning. Previous works that use this feature extraction technique are analyzed and expanded upon by utilizing a variety of different wavelets as well as other color-spaces with the goal of achieving higher result metrics …

A Heuristic Approach To Portrait Segmentation And Its Application To Synthetic Bokeh Generation, Charles J. Snead

Master's Theses

Segmentation of portrait images is an important technique used to separate the foreground and background of an image. This separation of layers is useful for selectively applying post-processing techniques to enhance the quality of the image, such as blurring the background. Automatic portrait segmentation is a complex process that can be completed with a high degree of accuracy using deep learning with neural networks, but training and inference are often very computationally expensive. This thesis aims to take a heuristic approach to portrait segmentation by combining classical image processing and computer vision techniques into a solution that can be run …

Enhanced Post-Capture Automatic White Balance For Srgb Images, Eric Huang

Master's Theses

Automatic white balancing (AWB) aims to correct color casts caused by varying illumination conditions, typically assuming access to RAW sensor data. However, many real-world applications involve only sRGB images that have already been processed by in-camera pipelines. In these cases, traditional AWB algorithms often underperform due to the nonlinear transformations done by these pipelines.

This thesis builds upon a data-driven color correction framework introduced by Afifi et al. that relies on RGB-UV histograms and learned color transforms. A revised automatic white balancing (AWB) framework that improves both color accuracy and runtime efficiency is proposed. A fallback routine is implemented to …

Modeling And Analysis Of A Hybrid Ac/Dc Green Seaport Power System With Photovoltaic Generation And Battery Energy Storage Systems, Corey Zaas

Master's Theses

This thesis investigates the modeling, simulation, and analysis of a Green Seaport power system integrating photovoltaic (PV) generation, battery energy storage systems (BESS), and coordinated protection within a hybrid AC/DC framework. The work improves a previously established model, enhancing it with detailed protection studies and simultaneous AC/DC power flow analysis using EasyPower software. The system was evaluated under a wide range of operating conditions, including varying solar irradiance, battery charge and discharge states, and both full and zero load conditions. Key performance indicators included voltage regulation, power factor behavior, equipment loading, protection device coordination, and total system power losses. Simulation …

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 …

Adversarial Voltage Transients In Multi-Tenant Fpga Environments, Andrew J. Gerber

All Graduate Theses and Dissertations, Fall 2023 to Present

A Field Programmable Gate Array (FPGA) is a special type of computer chip that can be reconfigured to implement a nearly unlimited number of functions. Recent trends have led some companies to offer cloud-based FPGA solutions. Researchers are exploring how to properly secure multi-tenant environments where the designs from two or more customers are placed on the same FPGA with logical and spatial isolation, though multi-tenancy is not yet commercially available in cloud FPGAs. The digital circuits within an FPGA require a clock to synchronize timing within the design. The maximum speed that this clock can run at is determined …

Lidar Scene Reconstruction Using Imagery And Frame Overlap From A Texel Camera, Blake Chamberlain

All Graduate Theses and Dissertations, Fall 2023 to Present

A small unmanned aerial vehicle (sUAV) can be used to reconstruct a large area of terrain by capturing 3D scans, consisting of LiDAR point clouds and an overlaid image, and combining the scans together. Forming a complete 3D scene using texel image data (fused LiDAR and digital image scans) from an entire flight can be computationally prohibitive on low-cost hardware, so combining registering scans is done using a streaming method which processes the scans in consecutive chunks. Depending on the flight pattern, matching points in the scene may be visible from scans which were not captured around the same time, …

Fibrin-Polycaprolactone Scaffolds For The Differentiation Of Human Neural Progenitor Cells Into Dopaminergic Neurons, Salma Paulina Ramirez

Open Access Theses & Dissertations

This project aimed to develop a tissue-on-a-chip platform for studying Parkinson's Disease (PD) using dopaminergic (DA) neurons. PD is a neurodegenerative disorder characterized by progressive loss of DA neurons, leading to involuntary movements and other symptoms. Early diagnosis and deeper understanding of PD pathogenesis are crucial for improving disease management and patient outcomes. To model PD in vitro, this research utilized human-induced pluripotent stem cell (hiPSC)-derived neural progenitor cells (NPCs) cultured on electrospun (ES) polycaprolactone (PCL) scaffolds. Given PCL's hydrophobicity, ECM-based biomaterial coatings, including Cell Basement Membrane (CBM) proteins, Matrigel, and Fibrin, were explored to enhance NPC adhesion, differentiation, and …

Inference Per Joule: A Performance Metric For Artificial Intelligence In Space Applications, Eduardo Macias Zugasti

Open Access Theses & Dissertations

The use of artificial intelligence (AI) has grown exponentially in recent years. This growth is driven in part by the significant advancements in computing capabilities, which have also increased exponentially. Computers have not only become more powerful but also smaller in size, thanks to the evolution of transistor technology. These developments have enabled AI to become a widely accessible tool, even in recreational activities such as image creation and entertainment videos.

More recently, the use of AI has extended to space applications, where it can enhance and optimize various tasks. However, space conditions pose significant challenges for conventional computers due …

Towards Mitigation Of The Light Network Load Performance Penalty Of The Network Link Outlier Factor (Nlof), Jaime Merin Guzman

Open Access Theses & Dissertations

Detecting and localizing faults in communication networks is critical to maintaining reliable and efficient network operations. The Network Link Outlier Factor with Most Likely Link (NLOF: MLL) algorithm has demonstrated its potential to automate this task but suffers from significant performance degradation under low network load conditions, where limited network flow data reduces its ability to localize faults. This thesis proposes and evaluates the performance of a synthetic traffic generation algorithm to be used with NLOF:MLL. This algorithm strategically injects synthetic flows that supplement the insufficient real network flows, thereby improving NLOF:MLL's performance under low-load conditions. Specifically, we select network …

Blind Construction Of A Party Check Matrix For Arbitrary Linear Block Codes, Aaron J. Womack

All Graduate Theses and Dissertations, Fall 2023 to Present

Communication systems are systems in which a transmitter sends data across a channel to a receiver. In any modern communication system, Forward Error Correction (FEC) is used to detect and correct errors that occur during transmission. As communication systems have developed over the years, many FEC algorithms have been proposed. Each FEC algorithm has parameters that can be selected based on the needs of the communication system. Typically, the transmitter and receiver are both aware of the FEC parameters, but in some cases the receiver may not know how the transmitter encoded its message. In this case, the receiver must …

Real Time Adaptive Control Of A Pid Via Genetic Algorithm Machine Learning Systems, Cemre Tas

Graduate Theses and Dissertations

The most common control method that is utilized by all industries across the world is the proportional-integrative-derivative controller (PID) due the relatively low cost and complexity of the system. However, there are draw-backs with PIDs, it is not adaptative to a changing system, so it works on nominal systems, and it starts breaking down when a system begins to have a non-linear response. The method chosen to overcome both is the utilization of machine learning with the use of genetic algorithms.

This method allows any PID system to be capable of adapting in real-time, while not adding significant additional cost …