Digital Commons Network^™

Performance Comparison Of A Two-Level And A Three-Level 1500v Three-Phase Grid-Tied Solar Inverter, Shawn Sproles

Electrical Engineering and Computer Science Undergraduate Honors Theses

With the global switch to renewable energy sources, photovoltaic energy has become an integral source to harvest from. When solar panels convert sunlight into a DC voltage, a grid-tied inverter is needed to transform this DC voltage into an AC voltage to interface with the AC grid. The most widely used topologies for grid-tied solar inverters are two-level three-phase inverters and three-level NPC three-phase inverters. Compared to two-level inverters, three-level NPC inverters have advantages such as lower EMI, lower THD, and lower switching losses. Moreover, three-level NPC inverters are shown to have higher efficiency in low-voltage applications at medium to …

Protocol-Aware Enforcement-Point Postcards And Collector Feedback For Ot/Ics Forensic Readiness And Closed-Loop Defense, Haden Fowler

Electrical Engineering and Computer Science Undergraduate Honors Theses

In this work, we apply P4-programmable switches to Operational Technology (OT) and Industrial Control System (ICS) traffic with the objective of turning enforcement decisions into structured forensic evidence that can also support fast, scoped feedback. OT investigations often rely on later correlation of endpoint logs, passive packet traces, and historian data, but those sources can be incomplete, hard to align in time, and missing the decision made at the enforcement point. We address this gap by implementing a P4-based enforcement switch that parses Modbus/TCP write traffic, applies protocol-aware policy checks, and exports protocolaware postcards to a collector. The collector stores …

A Study Of Visualized Diagnostics In Early Stage Digital Twin Implementation Of An Industrial Control System, Michael R. Kinzel

All-Inclusive List of Electronic Theses and Dissertations

Industrial Control Systems (ICS) are used for process control in almost all industries. An ICS combines Operational Technologies (OT) with Information Technologies (IT) to allow human supervision of a process through surveillance of process variables and manipulation of controlling elements such as valves to maintain stable process conditions. ICSs have been in-service for several decades and may remain operational past their technological service life. Organizational personnel interact with the ICS through visual displays that both indicate the process variables and also the controlling elements. The Human Machine Interface (HMI) allows visibility of the process and the ability to manipulate controlling …

Ionospheric Plasma Electron Density Measurement And Theory Using Impedance Probe Techniques, Justin Wellington

All Graduate Theses and Dissertations, Fall 2023 to Present

The ionosphere plays a critical role in how radio frequency (RF) signals, like those used in Global Position System (GPS) satellite communications, travel through space. Disturbances in the ionosphere, such as equatorial plasma bubbles (EPB), scatter these signals and cause communication dropouts or navigational errors. To study these conditions, spacecraft use instruments that measure the surrounding plasma directly. One of these instruments is an impedance probe, which applies a small electrical signal to a sensor and determines electron density from the measured impedance.

This thesis improves the modeling and interpretation of impedance probe measurements. A numerical method is developed that …

Low-Cost Rf Exposure Monitoring With Tinyml Prediction, Sanad Sahawneh

Nanoscale Science & Engineering (discontinued with class year 2014)

The proliferation of wireless technologies has produced a dense, increasingly heterogeneous radio-frequency (RF) environment that surrounds modern life. While regulatory bodies such as the Federal Communications Commission (FCC) and the World Health Organization (WHO) maintain exposure guidelines, the tools that ordinary people, educators, and small institutions can use to actually observe RF exposure in their own spaces remain expensive, specialized, and largely confined to professional laboratories. Spectrum analyzers and calibrated field probes routinely cost between five hundred and one hundred thousand dollars per unit, placing continuous local monitoring out of reach for most environments where exposure questions are most natural …

The Role Of Operational Context In Shaping Energy Management Portfolios: A Comparative Case Study Of Two Manufacturing Facilities, Cynthia Aranda

Theses and Dissertations

Using two facilities as illustrative examples, this research investigates how a manufacturing plant's operational and financial context may influence its investment decisions in energy-efficiency measures. This challenges the primacy of the simple payback period (SPP) as a screening tool and instead demonstrates the role of operational context in investment decision-making. To this extent, this study is anchored to a qualitative comparative case study analysis of two ITAC energy assessments for two manufacturing plants in Texas: a higher value-added aerospace MRO plant (GE Aerospace, TR0060) versus a cost-sensitive automotive stamping plant (UMP Metal Stamping, TR0061). The two cases illustrate two different …

Sub-Ghz Propagation Along Freight Trains For Wireless Onboard Communications, Dario Hinojosa

Theses and Dissertations

With the increasing length of freight trains, maintaining reliable wireless communication for onboard sensors has become increasingly challenging. Sub-GHz communication bands are a promising solution due to their long-range capability and suitability for rural railway environments. This study analyzes radio wave propagation around freight railcars to evaluate path loss and determine how antenna polarization affects wireless communication performance.

Time-domain full-wave electromagnetic simulations were performed using simplified railcar models and later validated through field testing using a vector signal generator, vector network analyzer (VNA), and spectrum analyzer. Various antenna polarization configurations were evaluated within the Sub-GHz Long Range (LoRa) frequency band …

Design And Reliability Analysis Of A Radiation-Tolerant On-Board Computer System For Martian Surface Missions, Jack Ryan

Master's Theses

Space environments present complex challenges for electronic devices, perhaps most notably in the form of radiation effects; the natural protections provided by Earth’s atmosphere and magnetosphere are largely absent in deep space and extraterrestrial environments, making single-event effects (SEE) a critical concern. Although radiation-hardened components offer near-immunity to SEE, they possess tremendous drawbacks in both cost and performance. To circumvent such issues, this thesis investigates the feasibility of leveraging a commercial-off-the-shelf (COTS) device, the AMD KRIA K24 system-on-module (SOM), for use in Martian surface missions.

Detailed models were used to predict SEE rates in the system, and system-level fault tree …

Neural-Network-Based Modeling Of Grid-Forming Inverters, Jacob D. Levesque

All Theses

Renewable energy production has grown significantly in recent years and continues to expand, resulting in an increasing number of inverter-based resources (IBRs) in the grid. As the number of IBRs in the grid continues to grow, grid-forming (GFM) inverters are becoming increasingly popular due to their ability to regulate voltage and frequency, providing increased grid stability and enabling islanding. As GFM inverters become more widely used in power systems, accurate and efficient models of their behavior are needed for system design purposes.

Emerging advances in neural networks have led to research on computationally efficient neural-network-based (NN-based) modeling approaches for inverters. …

Implementation Of A Local Llm Serving System For Agentic Ai, Zhiheng Ni

All Theses

This thesis presents a system that allows large AI models to run directly on personal devices instead of relying on cloud servers. Recent advances in artificial intelligence, especially large language models (LLMs), have made it possible to build powerful applications such as chatbots, coding assistants, and intelligent agents. However, most of these systems run in the cloud, which raises concerns about privacy, latency, and cost.

To address these issues, this work develops a local AI serving system that runs efficiently on a specialized hardware component called a Neural Processing Unit (NPU). The system provides a unified interface that supports multiple …

Introduction To The Special Issue On Computer Modeling For Future Communications And Networks, Wenbing Zhao, Pan Wang

Electrical and Computer Engineering Faculty Publications

No abstract provided.

Enhancing Reliable Performance Of Microgrids With Autonomous Control Of Distributed Energy Resources, Sahand Liasi

All Dissertations

This dissertation presents a comprehensive investigation into enhancing the reliability, efficiency, and autonomous operation of modern power networks through advanced microgrid integration and control strategies. The research addresses critical challenges across three interconnected domains: microgrid control, thermodynamic modeling of heat recovery system (HRS), and optimal distribution network reliability.

In the realm of microgrid control, this work introduces novel methodologies for grid forming inverter-based resources (IBRs). A significant contribution is the development and validation of an "Auto Frequency Change" controller, which drastically reduces microgrid synchronization time with the main grid from several minutes to approximately four seconds, with theoretical potential for …

Safe Control Design For Quadruped Locomotion In Unstructured Environments Using Linear Transfer Operators, Sriram Sundar Krishnamoorthy Shankara Narayanan

All Dissertations

Deploying quadruped robots in unstructured, obstacle-rich environments requires control and planning methods that remain safe and reliable despite complex terrain geometry, limited sensing, and inevitable modeling errors. This thesis develops operator-theoretic tools for safe control design of robotic systems using linear transfer operators, with a focus on quadruped locomotion in unstructured environments. The central goal is to develop a unified operator-theoretic framework for safe control design based on the Perron–Frobenius (P–F) and Koopman operators. In particular, the thesis leverages \emph{density functions} to develop safe navigation frameworks in the dual space of densities. In the operator-theoretic perspective, the P–F operator governs …

Mitigating Inertial Measurement Unit Drift In Quadcopter Trajectory Tracking Using Kalman Filter Sensor Fusion With Global Positioning Measurements, Juan Sandro Caballero Aguilar

Graduate Theses and Dissertations

Unmanned Aerial Vehicles (UAVs) like quadcopters are widely used in civilian and military applications such as farming, photography, search and rescue missions, and autonomous navigation and motion. The performance and stability of these systems depend on accurate state estimation, which provides real-time information about the vehicle’s position, velocity, and orientation. However, achieving reliable state estimation is challenging due to sensor noise, measurement uncertainty, and inaccurate modeling. Common navigation sensors such as the Global Positioning System (GPS) and Inertial Measurement Units (IMUs) exhibit complementary characteristics. GPS provides absolute position measurements but suffers from noise, multipath effects, and low update rates, while …

Electrical Resilience In Water Treatment Plants: An Extreme Weather And Lightning Protection Study, Genesis Martinez

Theses and Dissertations

Water treatment plants (WTPs) are vital infrastructure systems that depend on sensitive electrical, electronic, and control equipment to ensure the continuous supply of safe drinking water and effective wastewater treatment. As global temperatures rise and climate change accelerates, the frequency and intensity of extreme weather events—such as hurricanes, flooding, and increased lightning activity—are becoming more pronounced. These events pose significant risks to the electrical resilience of water treatment facilities, often leading to power outages, equipment failures, grid instability, and prolonged service disruptions. This report explores the impacts of extreme weather, with a particular focus on lightning and electrical surges, on …

Learning Global Context For Sparse Activity Recognition In Lengthy Recordings With Limited Dataset Size, Zeyu Tang

All Dissertations

This dissertation describes methods to analyze lengthy recordings of data in order to detect sparsely occurring activities. The narrative below describes the progression of research that led to the development of these methods and their generalization into a unified framework. My research started with designing models for dietary monitoring, including detecting meals from day-long recordings and detecting intake gestures from meal-length recordings. Both tasks share some common characteristics: (a) the target event takes only a small portion of data recordings, and (b) there is global context within full-length data recordings that can help a model make better decisions. After finishing …

Versatile Exoskeleton Control Paradigms For Agile Human Locomotion: Task-Agnostic And Stability-Augmented Assistance, Miao Yu

All Dissertations

Lower-limb exoskeletons have shown great potential for assisting human locomotion, but designing controllers that provide assistance across diverse locomotor tasks and under external perturbations remains a major challenge. Many existing controllers for steady-state walking rely on pre-defined reference trajectories, which constrain voluntary human motion and limit adaptability across tasks. Moreover, they usually assume stable walking, while their performance under unstable conditions remains largely unexplored. In addition, existing gait stability augmentation controllers are often reactive rather than proactive to unstable conditions. In this dissertation, we propose control frameworks that preserve voluntary human motion while addressing two major challenges: providing task-agnostic assistance …

Design Of An Extensible And Scalable Data Acquisition System For Pulse Shape Discrimination, Prince John

McKelvey School of Engineering Graduate Student Theses & Dissertations

This thesis presents the design and development of a highly scalable, end-to-end data acquisition (DAQ) system for nuclear physics experiments that can be deployed in configurations ranging from a few to thousands of detector channels. The system is built as an extensible platform composed of modular 16-channel chipboards that support a wide range of scintillator and detector types and perform real-time, on-board data sparsification and pulse-shape processing. Three versions of the chipboard have been fabricated to date.

The DAQ architecture is based on a family of analog pulse-shape-processing application- specific integrated circuits (ASICs) developed by the IC Design Laboratory at …

Conditioning Hierarchical Diffusion Transformers On Rf Circuit Parameters, Ethan Morton

McKelvey School of Engineering Graduate Student Theses & Dissertations

As modern ML techniques have become increasingly advanced, they have begun to be integrated into wireless RF systems for classification, identification, and spectrum management. Deep Neural Networks (DNNs) enable RF system operators and designers to design more flexible systems with greater robustness to errors and attacks. However, neural networks require significant amounts of properly annotated data to train. Current data labeling methods lack the ability to obtain reliable true labels for circuit properties such as carrier frequency offset (CFO), power amplifier (PA) non-linearity, and in-phase/quadrature (IQ) imbalance. This thesis investigates the efficacy of a novel architecture, RF-Diffusion, for generating high-quality …

Data-Driven Multimodal Mri Representation Learning For Subtype Discovery And Disease Progression Modeling In Parkinson’S Disease, Zihan Zhou

McKelvey School of Engineering Graduate Student Theses & Dissertations

Parkinson’s disease (PD) exhibits substantial clinical and neuroanatomical heterogeneity, limiting robust patient stratification and clinically meaningful progression modeling from MRI. We propose a unified multimodal 3D generative representation-learning framework that learns an interpretable latent space from co-registered baseline T1/T2 MRI with an edge-aware channel. Confound-corrected latent embeddings support unsupervised subtype discovery, while disease duration provides weak supervision to orient a continuous progression axis. On an independent external cohort (PPMI, N=171), the discovery-trained subtype structure shows significant partial replication (ARI=0.35; permutation test p=0.001) and enables longitudinal clinical stratification: mixed-effects modeling reveals subtype-dependent MDS-UPDRS III progression, with the strongest effect in subtype …

Temporal Logic Planning In Semantic Maps Of Unknown Environments Using Tl-Rrt, Dongrui Yang

McKelvey School of Engineering Graduate Student Theses & Dissertations

Autonomous mobile robots are increasingly expected to perform complex missions in unstructured environments. Traditional path planning approaches handle simple point-to-point navigation, but struggle with complex tasks that involve temporal and logical orderings of objectives. Linear Temporal Logic (LTL) provides a method for complex missions (e.g., sequential visits to multiple targets or surveillance tasks) in a strict way. This thesis presents an integrated planning framework that enables a robot to satisfy LTL-based task specifications in an unknown environment by combining a Temporal Logic RRT* (TL-RRT*) planner with semantic mapping. The robot builds a semantic map of its environment online using simultaneous …

Robust Hardware Trojan Detection Leveraging Dual‑Domain Features And Stacked Ensemble Learning, Sefatun-Noor Puspa

All Theses

In Cyber-physical systems rely on sensors, communication, and computing, all powered by integrated circuits (ICs). These ICs are vulnerable to malicious hardware attacks, with hardware Trojans being one of the stealthiest threats. Trojans are malicious implants in the circuitry, which are often inserted during design or fabrication stages. This stealthy addition remains dormant until triggered and might cause functional disruptions or sensitive information leakage once triggered. Traditional IC validation methods, such as functional testing and logic analysis, usually fail to capture these subtle anomalies because hardware Trojans are intentionally designed to mimic normal circuit behavior. They often remain dormant under …

Laser-Induced Acoustic Signal Generation, Resonance Characterization, And Optical Sensing In Metallic Plates, Xinghang Zhao

All Theses

This thesis investigates laser-induced acoustic signal generation, resonance characterization, and optical sensing in metallic plates as a foundational study for damage-sensitive inspection. Rather than presenting a complete defect-detection system, the work focuses on how measurable acoustic responses can be generated, amplified, and interpreted in a controlled laboratory setting. Experiments showed that pulsed-laser excitation can produce strong and repeatable acoustic responses in metallic structures. Repetition-rate sweeping identified narrow resonant responses, including a cantilever resonance at 57.862 kHz and a maximum circular-disk response at an FFT frequency of 48.8 kHz with a laser repetition rate of about 49.1 kHz. High-Q resonances exceeding …

Enhanced Situational Awareness Of Solar Pv Plants For Near Real-Time Planning And Operation In Modern Power Systems, Michael A. Walters

All Theses

Solar photovoltaic (PV) plant development and utilization is increasing worldwide but remains intrinsically challenged by its large dependence on highly variable weather conditions and operating states. This paper presents a framework to leverage three new situational awareness indices (SAIs), namely: weather condition index (WCI) to gauge operational performance based on environmental states, operational complexity index (OCI) to indicate the severity of power generation reductions, and photovoltaic generation index (PVGI) to provide a final determination of the impact on power generation and to bolster situational awareness in planning and operational contexts for solar PV plants. This is accomplished by exploiting the …

Development Of Low-Cost Triaxial Force Sensor For Measurement Of Human-Exoskeleton Interaction Forces, Hamdan Khan Sarvathullah

All Theses

Contemporary research suggests that shear force is a major contributor to discomfort and pressure injury. However, the variation of shear forces during human-exoskeleton interaction dynamics is a highly unexplored field. The high cost of commercial triaxial force sensors may be a major factor in the notable lack of research in this field. Therefore, in this paper, we present a low-cost, 3D-printed triaxial force sensor designed specifically to measure the triaxial interaction forces between an exoskeleton and its user. The triaxial force sensor uses Carbon-Black/Silicone Rubber (CB/SR) strings to measure shear forces, whereas the normal force is measured with a Force …

Design And Optimization To Advance Silicon Carbide Modules For Medium Voltage High Power Applications, Ahmed Ismail

Graduate Theses and Dissertations

The commercial availability of the first 10 kV silicon carbide (SiC) MOSFET removes the principal semiconductor barrier to medium-voltage power conversion, enabling converter topologies that are structurally inaccessible to silicon IGBT solutions at this voltage class. This dissertation presents the characterization infrastructure, device-level data, and preliminary system-level validation needed to advance the deployment of the third-generation 10 kV SiC MOSFET in converter applications. A custom-built 10 kV double-pulse test platform is developed with a fully documented component-sizing methodology, custom medium-voltage magnetics, and a measurement infrastructure capable of high bandwidth waveform capture at kilovolt common-mode potentials. On this platform, the third-generation …

Simultaneous Carrier, Cargo, And Functional Tracking Of Lipid Nanoparticles, Hannia Vanessa Balcorta Muñoz

Open Access Theses & Dissertations

Lipid nanoparticles (LNPs) have become effective delivery vehicles in nanomedicine, particularly for nucleic acid-based treatments. However, a major limitation remains in the field regarding the simultaneous monitoring of the nanoparticle carrier, its encapsulated payload, and the resulting functional protein production in both in vitro and in vivo systems. Furthermore, traditional lipophilic dyes employed for labeling LNPs frequently exhibit incompatibility with tissue-clearing methods, such as CLARITY, due to signal loss following lipid removal. This research developed and evaluated a new fluorescent labeling method using CM-DiI, a dye that reacts with thiols, for multimodal tracking of LNPs. CM-DiI was included in the …

Transient Mitigation In Dual Active Bridge Converter Using An Auxiliary Converter With High-Frequency Selective Control For Load Step-Down Condition, Sachith Dilshan Wijesooriya

Masters Theses

Dual Active Bridge (DAB) converters are widely utilized in applications such as electric vehicles, renewable energy systems, and solid-state transformers due to their high efficiency, galvanic isolation, and bidirectional power transfer capability. However, during rapid load transitions, DAB converters frequently exhibit significant output voltage overshoot and prolonged settling times, which increase device stress and adversely affect system reliability. This thesis proposes an auxiliary-circuit-based transient mitigation method to address these limitations. The auxiliary circuit, implemented as a bidirectional Buck–Boost stage, operates in Boost mode during load step-down events to absorb excess energy and suppress the resulting voltage overshoot. The design of …

Dynamic Load Assessment Of Pem Fuel Cell Systems Under Pid-Based Control Strategies For Sustainable Operation, Tarek Abedin, Paw, Normy Norfiza Abdul Razak, Chen Chai Phing, Yaw Chong Tak, Monowar Mahmud, Manzoore Elahi M. Soudagar, T. M. Yunus Khan, Mohammad Tariqul Islam, Mohammad Nur-E-Alam

Research outputs 2022 to 2026

Proton exchange membrane fuel cell (PEMFC) systems’ reliable operation under variable load conditions is a significant challenge because of voltage fluctuations, transient variations, and the high computational requirements of sophisticated control techniques like intelligent and model predictive controllers. Even while these state-of-the-art methods provide great precision, complexity and cost often limit their real-time applicability, underscoring the need for a simpler but efficient control solution. To achieve effective voltage regulation in PEMFC systems, this study suggests a DC–DC buck converter in conjunction with a comparator-based proportional–integral–derivative (PID) control technique. In order to provide stable operation under both constant and changing load …

Quantifying Spatiotemporal Ev In-Motion Load Dynamics For Flexible Distribution Grid Operations, Travis Newbolt

Open Access Theses & Dissertations

The emergence of novel in-motion Electric Vehicle (EV) charging through Dynamic Wireless Power Transfer (DWPT) technology is enabling the transformation of traditional roadway infrastructures into fully integrated Electrified Transportation Networks (ETNs) by the direct coupling of roadways with electric power grids. This paradigm has the potential to improve charging safety, extend driving ranges, reduce EV manufacturing costs through smaller battery sizes, and shift EV charging demand to periods when Distributed Energy Resources (DERs) are more readily available. In addition, the transition to ETNs can improve air quality and reduce noise pollution by displacing fossil fuel consumption from vehicles to centralized …