Digital Commons Network^™

Position Sensor Offset Fault Calibration In Speed-Regulated Pmsm Drives, Ujala Anuradhi Maha Gamage

Masters Theses

Speed regulation of electro-mechanically actuated systems is common across broad application segments, including industrial and residential sectors. The increasing demand for efficient energy conversion has made permanent magnet synchronous machines (PMSM) a preferred choice in modern applications. Vector controlled PMSMs in speed regulation mode being the dominant form of control, accurate speed and position measurement is crucial. However, a misalignment in the position sensor with respect to the true rotor zero position in speed regulated PMSM drives leads to inefficient energy conversion with the possibility of unstable motor behavior. The considered position sensor offset error fault, under severe fault modes, …

Enhancing Grid Integration Of High-Power Loads Through Modular Unfolding-Based Power Conversion With Decentralized Control, Sanat R. Poddar

All Graduate Theses and Dissertations, Fall 2023 to Present

The transition to electric vehicles (EVs) is a critical step toward reducing greenhouse gas emissions and creating a cleaner, more sustainable transportation sector. However, many drivers — particularly those operating larger vehicles such as trucks and buses — face significant challenges, including limited driving range and lengthy charging times. High-power, fast-charging stations, which can rapidly replenish EV batteries, are therefore essential for mitigating these barriers and making electric transportation practical across all vehicle classes.

Despite the promise of electric vehicles, deploying high-power fast-charging stations presents significant challenges. They require large amounts of electricity, making them expensive to install, operate, and …

Design, Control, And Optimization Of Unfolding-Based Ac-Dc Topologies With Three-Port Resonant Converters For Electric Vehicle Battery Charging Applications, Aditya Zade

All Graduate Theses and Dissertations, Fall 2023 to Present

The global effort to reduce greenhouse gas emissions and reliance on fossil fuels has made electric mobility a cornerstone of sustainable transportation. This transition is driving demand for advanced charging infrastructure and more efficient power conversion systems. Power converters play a central role, not only in enabling reliable EV charging but also in integrating renewable energy sources with the grid. Because of the large amount of power involved, these converters must operate efficiently, reliably, and at low cost. Conventional high-power chargers often use two stages of conversion, which are effective but limited by size and energy losses. To overcome these …

Developing Standardized Testing Datasets For Benchmarking Automated Quality Control Algorithm Performance With Aquatic Sensor Data, Ehsan Kahrizi

All Graduate Theses and Dissertations, Fall 2023 to Present

Advances in water monitoring technologies have led to a large increase in the amount of data collected from rivers, lakes, and other water systems. However, ensuring that these data are accurate and reliable remains a major challenge. Traditional data quality checks are done manually by a technician, which can be slow, inconsistent, and not practical for real-time monitoring. This research addresses these challenges by developing standardized datasets for testing computer-based methods that automatically detect and correct errors in water data. Using information from the Logan River Observatory in northern Utah, we created a step-by-step process to identify, categorize, and label …

Extremum-Seeking Approach For Real-Time Self-Healing Of Position Sensor Offset Error In Non-Salient Pmsms, Ramitha Kalhara Dissanayake Ralalage

Masters Theses

The inherent advantages of permanent magnet synchronous machines (PMSMs), such as high efficiency, has led to their frequent use in industry, including safety-critical applications, such as transportation electrification. The accurate measurement of the rotor position is key to achieving efficient and reliable field-orientation-based torque regulation. With the high reliance on the rotor position measurement, position sensor fault diagnosis and mitigation facilitate a layer of safety. Conventional methods for compensating position sensor offset errors in electric drives typically depend on accurate knowledge of motor parameters. However, these parameters are often subject to variation due to temperature changes, system aging, and other …

Flood-Level Estimation Using Aerial Imagery, Yisen Zhang

Electrical & Computer Engineering Projects for D. Eng. Degree

Reliable flood-level estimation using aerial UAV (Unmanned aerial vehicle) imagery is essential for effective post-disaster assessment and rapid emergency response. This study utilizes a UAV-based dataset, referred to as the UVA dataset, which integrates multiple public datasets and manually labeled UAV images, together with a multi-stage vehicle-centric framework for flood-depth estimation. The UVA dataset integrates images from multiple public sources, including Unmanned Drone Water Assessment (UDWA), Unmanned Aerial Vehicle Detection and Tracking (UAVDT), Car Parking Lot (CARPK), and additional UAV-view images collected from the internet, followed by manual annotation for water depth, viewing angle, and altitude labels. In the proposed …

Rainfall-Runoff Modelling In An Indonesian Humid Tropical Area Using Satellite-Based Precipitation Products, Noordiah Helda

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

This dissertation explores three rainfall-runoff models in the humid tropical regions of Indonesia using satellite-based precipitation products (SBPPs) and develops integrated machine-learning modeling frameworks. Several ground-based observations from BMKG (Badan Meteorologi, Klimatologi, dan Geofisika (also known as the Indonesian Agency for Meteorology, Climatology, and Geophysics)) stations across Indonesia (133−165 stations) are compared and evaluated against satellite products, indicating that GPM performs well, with R-squared values ranging from 0.54 to 0.76 and correlation coefficients ranging from 0.45 to 0.69, respectively.

In the Martapura Watershed, South Kalimantan, due to a lack of observational discharge data, streamflow was generated using the FJ Mock …

Residential Hvac Installation Faults: Field Prevalence, Drivers, And Energy Impacts, Seyed Ali Rooholghodos

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

Faults in residential comfort systems can have detrimental effects on the performance of the system, reducing the energy efficiency, affecting indoor comfort, and shortening equipment lifespan. Many of the faults occur at installation. However, there has not previously been a systematic and nationally representative study to indicate the prevalence of the faults, meaning the distribution of faults by fault type and fault intensity. Understanding true fault prevalence is essential to be able to identify derivers, and to assess the incremental electricity consumption of the new installation systems.

This study presents on-site data from 341 new central cooling systems—air conditioners and …

Degradation Of Cobalt Chrome Molybdenum Hip And Knee Implants In Vivo And In Vitro, Peter William Kurtz

All Dissertations

Cobalt Chrome Molybdenum (CoCrMo) remains a popular material choice for femoral condyles in total knee arthroplasty and for acetabular liners in dual mobility total hip designs. CoCrMo has been phased out of conventional THA designs due to its correlation with adverse effects such as ALTR and ALVAL. It is less understood if the mechanisms (i.e. abrasive wear to the surface of the implant) that release metal ions into the surrounding tissue occur at similar rates as seen in conventional THA. Additionally, it is unknown what effect the secondary damage modes such as electrocautery damage and adhesive wear have on these …

Experimental Characterization Of An Additively Manufactured Porous Gyroid Air-Cooled Heat Sink, Grant S. Resler

Mechanical Engineering Undergraduate Honors Theses

This paper presents the development of a ducted test facility designed to evaluate heat sinks efficiency at varying air velocities. This enables the evaluation of both heat transfer and pressure drop performance. These metrics are essential to the overall efficiency of heat sinks and help identify the optimal air velocity to achieve the desired thermal performance. A standard plate fin heat sink was used as a control for comparison to a novel heat sink. The specialized heat sink geometry was generated using nTop, a generative design software focused on additive manufacturing. This design was fabricated via Direct Metal Laser Sintering …

A Study On Utilizing Coherently Coupled Orbital Angular Momentum Beams For Maritime Sensing And Communication, Evan Robertson

All Dissertations

A large portion of the world is covered in water which introduces a couple of key challenges in communication and sensing systems. The impact of particulates in the water will limit the ability to successfully transmit information through the water. The study of how the channel impacts specific frequencies and the ability to transmit more information at a single time can limit the impact of this environment in how it degrades an optical communication system. In sensing applications, it is important to detect information related to an object’s motion which will either be towards or away from a system, or …

Exploratory Diver Geotechnical Equipment (Edge), Angel Villicana, Merrick Zellers, Erik Heuchert, Lucas Heuchert

Mechanical Engineering

The goal of this report is to showcase how our final Core Sampler design and prototype address the needs of Navy Divers. Geotechnical equipment for Navy divers has not been updated since the early to mid-1980s, resulting in imprecise and outdated sampling methods. The primary purpose of this project is to enhance, modernize, and redesign a tool to collect a minimally disturbed core sample of the seabed for geotechnical evaluation. This report presents the full development of our project from concept to verification and final outcomes. It begins with the statement of disclaimer, followed by a four-panel executive summary and …

Development And Test Of An Automatic Mass Balancing System For Cal Poly's Spacecraft Attitude Dynamics Simulator, Cameron B. Zorio

Master's Theses

The Cal Poly Spacecraft Attitude Dynamics Simulator (SADS) is an ongoing project to develop an air-bearing platform capable of recreating on-orbit rotational dynamics with near frictionless and torque-free rotations. However, any offset between the platform's center of rotation and its center of mass will introduce a torque due to gravity.

This thesis presents the design, implementation, and experimental evaluation of a low-cost, automatic mass balancing system for the SADS to address this challenge. A new modular sliding mass system was developed that overcomes issues faced in previous iterations of the SADS, providing real-time positional control of the masses and a …

Using Hydraulic And Hydrologic Modeling To Determine Scour At Toro Creek Under Climate Change Conditions, Gabriel E. Alaniz

Master's Theses

ABSTRACT

This study evaluates bridge scour at the Toro Creek crossing of Highway 1 in Morro Bay, California, under present conditions and future climate conditions with more frequent extreme rainfall events. California infrastructure is becoming increasingly vulnerable to extreme storm events and increased intense precipitation events brought by climate change. This analysis focuses on the calculation of scour for both the northbound and southbound spans. Highway 1 plays a vital role in California’s coastal transportation infrastructure by carrying more than 20,000 vehicles daily (Caltrans, 2017). In this thesis, a hydrological model (HEC-HMS) is used to simulate runoff under present-day and …

Curvilinear Image Segmentation Using Multiscale Variational U-Net, Rebekah Fortes

LSU New Orleans Theses and Dissertations

Segmentation of curvilinear structures such as water contours, cracks in cement, and vascular networks in biomedical imaging, poses unique challenges due to extreme class imbalance, irregular morphology, low contrast against complex backgrounds, and the need to preserve global connectivity while detecting fine-scale details. We propose a Multiscale Variational U-Net (MSVU-Net) architecture designed specifically to address these challenges. The model integrates multiscale convolutional filters to capture both global context and local detail, while embedding a variational model in the bottleneck layer to enhance structural representation. To mitigate class imbalance and improve fidelity, the network optimizes a hybrid loss function that combines …

Realization Of Deterministic Quantum Circuits For Non-Deterministic Or Incompletely Specified Quantum State Machines, Manjith Kumar, Marek Perkowski

Electrical and Computer Engineering Faculty Publications and Presentations

In classical logic design, there are machine learning methods based on converting a set of input-output traces to non-deterministic automata that are then converted to deterministic automata and synthesized using logic gates. This approach has not yet been extended to quantum automata. In this paper, we present a method to convert a set of input-output traces to a non-deterministic automaton, which is then converted to an incompletely specified multi-output Boolean function. The existing logic synthesis approaches for designing quantum circuits are insufficient to handle incompletely specified functions. So, we present a novel algorithm to synthesize logic functions with don’t cares …

Llm-Powered Question Answering For Object States In Virtual Reality, Shiyi Ding

Master's Theses

Recent advances in large language models (LLMs) and multimodal large language models (MLLMs) enable natural language–based querying in virtual reality (VR). However, VR environments are highly localized, personalized, and dynamic, making it challenging for general-purpose models to answer environment-specific queries or reason about subtle object state changes. To address these challenges, this thesis develops two systems for 3D question answering in VR.

First, we present RAG-VR, the first retrieval-augmented 3D question-answering system designed for VR. RAG-VR augments an LLM with external knowledge retrieved from a localized knowledge database and includes a pipeline for extracting environmental and user-related information. To improve …

Polydopamine-Coated Magnetic Nanoparticles Data, William G. Pitt

ScholarsArchive Data

This data archive contains raw data and processed data related to research and development of magnetic nanoparticles that adhere to bacteria. This data is the foundation of data in the MS thesis of Bowen Houser, and publications and presentations related to that research effort. Polydopamine-coated magnetic nanoparticles are found to be very adhesive to gram-positive bacteria, and less adhesive to gram-negative bacteria. These data files contain information for S. aureus, S. epidermidis, S. mutans, E. coli, P. aeruginosa, and N. perflava. Some data include the kinetics of capture.

Feed Network Design For Passive Beamforming In Hemispherical Phased Arrays, Daniel Flores

Theses and Dissertations

This thesis presents the design, fabrication, and evaluation of a four-element microstrip patch antenna array with a passive 1 to 4 corporate feed network operating at 5 GHz. A single inset-fed patch was developed on Rogers DiClad 880 to ensure accurate tuning and mechanical flexibility, achieving a measured resonance of 5.009 GHz with excellent return loss. The corporate feed network, synthesized using T-junction dividers and quarter-wave transformers, demonstrated strong impedance matching, balanced amplitude distribution, and broadside realized gain near 10 dBi when integrated with the array.

Beam steering was examined through simulation-based phase control, revealing effective scanning up to approximately …

Rapid Prototyping Of Low-Cost Sensor Systems Towards A Platform For Upper Limb Posture Estimation, Russell Rathbun

Electrical Engineering and Computer Science Undergraduate Honors Theses

Physical therapy requires patients to perform repeated actions to achieve meaningful results in rehabilitation. This thesis explores production methods and various sensor systems by utilizing rapid prototyping, inertial measurement units (IMUs), and capacitive sensor arrays (CSAs). CSAs can be made from a wide ar- ray of materials and techniques including 3d printing and laser ablation–to rapidly create CSAs that can be custom fit to enable proximity, force, and touch detection. IMU and CSA systems individually are able to track upper limb movements, ges- tures, and positions. This combination of sensors enables accurate upper limb pos- ture estimation of patients. This …

Mozgus, Damian Cerda, Madison Lopez

Computer Science and Software Engineering

The indie game market is flooded with genre experiments, yet few successfully combine fast-paced action with meaningful strategic decision-making. Our project aims to fill this gap by creating a game that fuses top-down action combat with resource-management tycoon mechanics. We found that in many games, the management phases lack mechanical stakes. Our goal was to intertwine these systems so that choices made in one phase meaningfully impact the other.

Integrating Machine Learning With An Fps Aim Trainer For Optimal Sensitivity Finding, Sharan Krishna

Computer Science and Software Engineering

First-person shooter (FPS) games often demand high levels of skill in aiming, which leads players to look for external tools to improve their performance. This is where the concepts of aim training and aim trainers come in, becoming an easily accessible outside source for players to strengthen their performance with custom scenarios outside a set game. While many aim trainers exist, they offer limited insight into player performance metrics or adaptability to varying aiming styles. Furthermore, most existing aim trainers lack a standardized way of correlating aim skill with real-world performance or personalized feedback. This aim trainer addresses these limitations …

Reinforcement Learning Based Security Schemes For Distributed Ai Systems, Ashan Chamath Gunawardena

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

Distributed machine learning (DML) is a component of modern intelligent systems, enabling collaborative training across devices such as mobile clients, vehicles, and edge networks. However, the decentralized nature of these systems introduces vulnerabilities, particularly data poisoning attacks that compromise model integrity and degrade performance. Traditional defenses, such as statistical filtering, robust aggregation, and privacy-preserving techniques, often struggle to adapt to overwhelming adversaries or operate under strict privacy and real-time constraints. This dissertation proposes the use of reinforcement learning (RL) and deep reinforcement learning (DRL) based misbehavior detection schemes that dynamically identify poisoning attempts in distributed AI systems, including federated learning, …

Ethical Decision-Making Processes In Authentic Environmental Engineering Contexts Through Systems Thinking And Team Collaboration Lenses: An Embedded Single Case Study, Toluwalase Eniola Brower

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

Ethical and professional responsibility is a critical learning outcome emphasized in ABET accreditation. However, ethics instruction in engineering education often lacks integration of system-level considerations such as economic, environmental, and societal contexts, that are essential for developing engineering solutions that ensure the safety and welfare of diverse stakeholders. This embedded single-case study investigated the integration of authentic ethics instruction within a junior-level environmental engineering course at a Midwestern U.S. university during spring 2025 and explores how civil engineering student teams within the course engage in ethical decision-making process during authentic problem-solving.

The instructional intervention consisted of four problem-based ethics modules, …

Lace Network Firmware: A Polarfire Fpga Network For Data Routing And Command Interfacing In Space Applications, Kade C. Howes

All Graduate Theses and Dissertations, Fall 2023 to Present

Modern small spacecraft rely on powerful yet efficient onboard compute devices to process data from sensors in real-time due to tight power and volume constraints. This work explores a new compute device system built from PolarFire Field-Programmable Gate Arrays (FPGAs), which are power-efficient, reprogrammable chips well-suited for space applications. The system connects via a central controller FPGA with one or multiple companion processing FPGAs, allowing sensor data to be quickly received and shared across the network. Standardized data formats and interfaces increase compatibility with spacecraft computers. By simplifying data handling and using high-speed communication links, this architecture makes it easier …

Friction And Texture Evaluation Of Asphalt-Based Binders As Alternatives To Epoxy-Based High-Friction Surface Treatments, Alireza Roshan, Magdy Abdelrahman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

High-friction surface treatment (HFST) is a safety-focused pavement treatment that restores and maintains pavement friction to reduce road accidents. Traditional epoxy-based HFSTs, while widely used, face challenges such as high costs, potential compatibility issues with the substrate pavement, and long-term durability under specific conditions. This study investigates asphalt-based alternative HFST, which is compatible with various pavement types and cost-effective and versatile solutions for a wider range of pavement applications. Performance and friction testing, including the British pendulum test, British wheel test, and dynamic friction test, were performed to examine the coefficient of friction (COF) before and after polishing with a …

Harnessing The Mechanical And Gelation Behavior Of Tyramine-Substituted Silk Fibroin Bioinks Through Integration Into A Modular And Low-Cost 3d Bioprinting Platform, Sourjjadeepta Biswas

Boise State University Theses and Dissertations

3D printing has become an indispensable tool in research labs across the globe. Yet, when it comes to bioprinting with custom or sensitive bioinks, accessible options remain limited. Commercial systems are often prohibitively expensive and restricted to proprietary materials, while DIY setups frequently lack the precision and compatibility needed for biologically relevant printing. Moreover, tunable bioinks that align with real-world biological constraints are still hard to come by. To address these gaps, we developed a modular, low-cost bioprinting platform tailored for tyramine-substituted silk fibroin (TA-SF) hydrogels-biocompatible materials known for their rapid gelation, tunable stiffness, and potential to support cell differentiation …

The Effect Of Loading Conditions And Specimen Size On The Tensile Strength Of Ring-Shaped Specimens, Kolby Scott Mcclure

Boise State University Theses and Dissertations

This study introduces a custom-built direct tension testing apparatus designed for ring-shaped rock specimens. The apparatus applies a uniform axial load to the inner surface of the ring and is compatible with standard geotechnical testing equipment. Using this device, 176 granite specimens sourced from Horseshoe Bend, Idaho, were tested under three configurations: Brazilian, indirect ring tension, and direct ring tension. Only specimens exhibiting valid diametrical splitting failure modes (126 out of 176) were included in the final analysis. Direct tension tests yielded the lowest tensile strengths, followed by Brazilian tests, with indirect tension tests producing the highest values. While scatter …

Stimulation And Recording Interfaces For Data Transmission To And From A Micro Neural Stimulation Device, Morgan Riley

Boise State University Theses and Dissertations

Advancements in neuromodulation for treating neurological disorders increasingly rely on selective peripheral nerve stimulation rather than whole-nerve activation. Traditional approaches engage all fascicles, causing off-target effects such as involuntary muscle contractions and pain. To address these challenges, this research proposes a minimally invasive microdevice that integrates wireless galvanic impulse communication with an epineural multi-contact nerve cuff. This design facilitates high-throughput, low-power stimulation, recording, and data transfer. Development efforts include optimizing neural stimulation protocols, validating deep tissue galvanic transmission, and fabricating a multi-channel nerve cuff for stable electrode–tissue interfacing. In parallel, custom depth-controlled intramuscular arrays enable high-density electromyography (EMG) recording during …

Lstm Network-Based Scheme For Automatic Characterization Of Power Quality Disturbances, Akram Elmitwally, Mohamed Nader

Mansoura Engineering Journal

Recognition of power quality (PQ) troubles is a critical task in the electrical power industry. Most previous works solve the classification problem using separate feature extraction phase and classification phase. Each phase has its own techniques, and consumes a computation time. This study proposes to utilize the long short-term memory (LSTM) network as a deep learning model to classify the PQ events in one shot. The LSTM network uses its particular processing to classify a PQ event signal directly by reading its time-sequence data. Then, a dedicated post-classification algorithm (PCA) extracts start time, end time, duration, amplitude, and total harmonic …