Engineering Commons^™

Real-Time Dynamically Feasible B-Spline Trajectory Generation For Unmanned Aircraft, David Lavae Christensen

Theses and Dissertations

Onboard aircraft systems must frequently plan dynamically feasible paths or trajectories to safely and quickly reach their goal position. Optimized B-splines are promising because they can guarantee kinematic feasibility in a computationally efficient manner and can be applied to a variety of vehicle models. However, current B-spline solutions do not adequately constrain trajectories to the physical limitation of the vehicles they are planning for, or are often too conservative. Most are also limited to path smoothing or require pre-optimized timing parameters. This thesis develops a real-time B-spline optimization-based trajectory generator capable of minimizing time while respecting the velocity, acceleration, and …

Design And Development Of A Clinical Decision Support System For The Diagnosis Of Parkinson’S Disease Using Artificial Intelligence, Saravanan S

Theses and Dissertations

Parkinson’s disease (PD) is a degenerative neurological condition marked by motor symptoms like tremors, bradykinesia, and stiffness. It is observed that early and precise diagnosis of this disease is crucial, as that will have a significant impact on effective disease management and intervention. This thesis explores the technical feasibility of applying AI techniques to recognize patterns from spiral and wave drawings, which are usually a unique signature type for PD patients.

The focus of the work is to diagnose the disease through novel deep transfer learning techniques, to diagnose the severity of the disease, and also to develop effective model …

A Personalized Chat Application For Career Profiling: A Case Study, Dhiraj Choithramani

Harrisburg University Dissertations and Theses

Artificial intelligence (AI) has rapidly transformed numerous fields over the past decade, significantly influencing industries such as software engineering and computer science. One of the most impactful developments in this area is the rise of AI-driven chat applications, which have evolved from simple, rule-based systems to sophisticated platforms capable of simulating human-like conversations. These chatbots are increasingly being utilized across various sectors, including customer service, healthcare, and education, to provide users with quick, personalized responses. This research paper presents a case study of a personalized chat application designed specifically for career profiling, leveraging advanced AI technologies to deliver contextually relevant …

Heat Transfer To Arrays Of Oscillating Impingement Jets, Alex Q. Clay

Doctoral Dissertations and Master's Theses

In gas turbine engines, the desire to increase turbine entry temperatures has become more relevant in order to increase engine efficiency. However, materials used in these engines can only withstand temperatures that are so high. Because of this, the ability to cool hot section components will always limit operating temperatures. Impingement cooling jets have become a common way of cooling due to the high rates of heat transfer that can be achieved. However, previous research has shown that the interaction of impingement jets with cylinder wake can improve the intensity and uniformity of heat transfer. The goal of this study …

Development And Application Of A Particle-Based Reactor Network Model For Entrained Flow Gasifier Design, Eric Christian Monson

Theses and Dissertations

A novel particle-based reactor network model (PRNM) was developed to predict the performance of a dry-feed, pressurized, single-stage, slagging entrained flow gasifier under various operational parameters. This model provides improved detail of particle conversion as a function of gasifier location, particle size, and fuel type not available in standard reactor network models. The model inputs were designed to allow changes in geometry, firing rate, stoichiometric ratio, fuel type, and inlet gas composition. Key performance metrics included the gas and refractory temperature profiles, axial gas compositions, and particle burnout. PRNM used a network of idealized reactors to specify the flow field …

Design And Validation Of Sensing Knee Sleeve Rehabilitation Device Utilizing Large Deflection Strain Gauges, Kurt Christian Jensen

Theses and Dissertations

Total knee arthroplasty (TKA) procedures are increasingly common in the US and globally. However, rehabilitation outcomes may be negatively affected by limited access to physical therapy and patients' tendency to not fully adhere to recommended exercises between therapy sessions. This study aims to develop a remote system to aid rehabilitation, building upon recent sensor development at Brigham Young University, providing physical therapy-like biofeedback during unsupervised at-home exercises. The system developed by this research consists of three primary components: (1) a sensor array for measuring leg/knee biomechanics, (2) a machine learning algorithm to predict knee flexion angle from the sensor data, …

Modular Approach To Soft Mobile Robots, Dimuthu Kodippili Arachchige

College of Computing and Digital Media Dissertations

Soft robot locomotion is a highly promising but under-researched subfield within the field of soft robotics. The compliant limbs and bodies of soft robots offer numerous benefits, including the ability to regulate impacts, tolerate falls, and navigate through tight spaces. These robots have the potential to be used for various applications, such as search and rescue, inspection, surveillance, and more. The state-of-the-art still faces many challenges, including limited degrees of freedom, a lack of diversity in gait trajectories, insufficient limb dexterity, limited payload capabilities, lack of control methods, etc. To address these challenges, this research introduces a modular approach to …

Vco Calibration Techniques And Design Of A 0.12-V Ultra-Low Supply Analog-To-Digital Converter, Shea Smith

Theses and Dissertations

Many analog-to-digital converters (ADC) quantize inputs using a voltage-controlled-oscillator (VCO). These VCO-based ADCs leverage time-domain processing to shape quantization noise and mismatch, which further increases their appeal. Despite these advantages, achieving good performance with a VCO-based ADC remains a significant challenge due to the nonlinear transfer characteristics of the voltage-to-frequency (V-F) conversion. VCO-based ADCs widely utilize coarse-fine readout to save power and hardware compared to counter-only converters. However, the timing mismatch due to the clock skew between the coarse and fine quantizers can lead to significant reconstruction errors. Chapter 2 proposes a digital calibration circuit to detect and correct coarse-fine …

Degradation Study Of Single Crystal Barium Titanate Capacitors Under Harsh Environment, Menglin Wang

Electrical Engineering Theses and Dissertations

Capacitors are critical for voltage source converter functionality. DC-link capacitors are known to have reliability issues. Resistance degradation at high temperatures is one of the primary failure modes in capacitors. The overall goal of this program is to improve the understanding of high voltage breakdown and resistance degradation in high dielectric constant inorganic ceramic capacitors, using single crystal BaTiO₃ as a model system to understand the impact and control of oxygen vacancy migration to maximize the long-term reliability of high voltage inorganic multi-layer ceramic capacitors, which allows higher frequency operation, reducing the size and cost of passive components in …

Activity Map Generation And Event-Based Sensor Processing With Spiking Autoencoders And Sparse Dictionary Learning, Jack Easton

Computer Science and Engineering Theses and Dissertations

This thesis explores the potential of Spiking Neural Networks (SNNs) in processing event sensor data and generating high-fidelity activity maps. Event sensors capture asynchronous binary events with high dynamic range, but traditional processing methods often fail to leverage their advantages fully. SNNs, with their asynchronous, event-driven nature, offer a promising alternative.

A Spiking Autoencoder (SAE) was employed in this thesis to handle the stochastic and sparse event data, integrating deep dictionary learning to enhance the feature space and improve activity map quality. The encoder, modeled after the VGG network, extracts features from event streams generated by speckle patterns, which are …

Empty State Electronics, Reza Farsad Asadi

Electrical Engineering Theses and Dissertations

Field emitter arrays (FEAs) have the potential to operate at high frequencies and withstand harsh environments, such as radiation and high temperatures. However, they are sensitive to gaseous environments. This study examines the impact of different gas environments on silicon (Si) and gallium nitride (GaN) FEAs. To investigate the failure mechanisms, a vacuum system was designed and fabricated to monitor emission uniformity using a phosphor screen. Additionally, a vacuum system was created to introduce high-purity gases into the chamber while operating the devices. The results indicate that both types of FEAs are susceptible to oxidizing environments. Argon (Ar) did not …

Development Of A Nephelometer For Characterization Of Calcium Oxalate Crystal Concentrations Within Solution, Conrad Small

Electrical Engineering Theses and Dissertations

The prevalence of kidney stones has been steadily increasing over the last 30 years, affecting both men and women across all age groups. This rise is largely attributed to lifestyle changes associated with technological advancements, such as more sedentary lifestyles, dietary shifts towards more processed foods, and an increased incidence of metabolic diseases like diabetes. Despite the growing prevalence of kidney stones, the methods for early detection have remained relatively unchanged. Current testing involves collecting urine samples over a 24-hour period and sending them to a lab for microscopic and dipstick analysis. This process provides a comprehensive overview of urine …

Predictive And Prescriptive Analytics For Minimizing The Cost Of Recidivism, Adreana Julander

Operations Research and Engineering Management Theses and Dissertations

A problem faced by the United States is the ever increasing prison population. There are inmates serving long sentences, new inmates being sentenced for the first time, and those who have previously served prison sentences that reoffend. The third group and the reduction of recidivism are the focus this dissertation. It is estimated that over 80% of inmates released from prison will reoffend within the next ten years. Is there an optimal sentence length that reduces that chance of an ex-convict reoffending? Are there programs or opportunities that some inmates have while incarcerated that reduce the probability they will return …

Enhancing Fundraising Strategies In Higher Education Through Machine Learning, Laith Alatwah

Electrical Engineering Theses

This thesis presents a comprehensive application of machine learning techniques, namely Fine Gaussian SVM and RUS Boosted Trees, to enhance fundraising strategies in higher education institutions. Analyzing a rich dataset from Blackbaud Raiser's Edge NXT, spanning 2012 to 2022, the study focuses on donor profiles, including demographics, donation history, and engagement patterns. Key demographic insights include the increasing engagement of younger donors (20-29 age group) and significant contributions from older donors (70-99 age group). Geographical trends are also examined, revealing distinct patterns based on donors' city, state, and ZIP code. The Fine Gaussian SVM model demonstrates moderate discriminatory power, with …

Modeling Advancement In Spacefaring Through Deep Learning, Peng-Hung Tsai

Theses and Dissertations

Predicting advancement in space exploration technology allows space agencies and companies to strategically allocate resources, prioritize missions, and explore collaborations on complex projects. This foresight acts as a roadmap for future exploration, making the best use of valuable resources. The present study employs spacecraft lifetimes as an exemplar of technological progress and proposes a novel forecasting model based on Long Short-Term Memory (LSTM) networks. Existing research often suggests an increasing exponential relationship between technology performance and time (the generalized Moore's Law). However, applying this model directly to spacecraft lifetimes has a limitation. Spacecraft lifespans are unknown at launch, and recent …

A Step Towards Automated Ethical Analysis In Journalism: Measuring Llms’ Performance In Extracting Sourcing Information, Jingsen Wang

Computer Science and Engineering Master's Theses

This thesis explores the potential of Large Language Models (LLMs) in automating the extraction of sourcing information from news articles, a crucial step towards enhancing transparency and ethical analysis in journalism. We evaluate the performance of two state-of-the-art LLMs, GPT-4 and Claude 3, in identifying and categorizing various source types across four diverse news articles. The thesis employs a zero-shot learning approach with two different prompt designs, assessing the models’ ability to adapt to varying source structures and prompt instructions.

Our findings reveal that while LLMs show promise in extracting sourcing information, their performance varies significantly across different article types …

Design Of A Portable Fast Scan Cyclic Voltammetry Device Utilizing Pulse Width Modulation For Waveform Generation, Nora Szymkowski

Masters Theses

Fast Scan Cyclic Voltammetry (FSCV) is a widely used electrochemical technique for real-time measurement of the brain’s chemical messengers, including the molecule dopamine, with high temporal resolution. Currently the financial burden of performing FSCV is quite high, ranging from $8,000 to $20,000+ making the barrier to entry nearly insurmountable for laboratories and classrooms at small institutions. The purpose of this project was to develop a Do-It-Yourself (DIY), portable, and cost-effective FSCV system for use in laboratory and classroom settings. The project aimed to create a compact and cost-effective system that could be used by researchers and educators to study dopamine …

Safety And Risk Management Strategies For Achieving Regulatory Compliance In Construction Projects, Danny Rodriguez

Harrisburg University Dissertations and Theses

The architectural and construction business places great importance on safety and regulatory compliance because of its inherent high-risk nature and strict legal obligations. The prevalence of accidents and infractions at construction sites underscores the imperative for enhanced safety management systems and compliance with rules, notwithstanding substantial endeavors. The main objective of this study is to examine the many elements that impact the effectiveness of safety management, adherence to regulations, and the development of a safety culture, with the ultimate purpose of improving safety outcomes on construction sites.

The issue statement pertains to the difficulties associated with safety management and compliance …

Multiphysics Simulation Of Biochar Adsorption Rates, Joseph Salerno

Graduate Theses & Non-Theses

An accepted carbon capture and sequestration (CCS) method to remove carbon dioxide from the atmosphere is via adsorption onto biochar. While the characteristics of the char are important and greatly impact the adsorption of CO2 molecules, the conditions in which the adsorption occurs are equally critical. Factors such as char particle size and quantity, environmental temperature and pressure, as well as outside driving mechanisms such as vibration frequency, driving force, and flow rates play an impactful role on how the char adsorbs CO2 particles. These factors and their effects will be studied in multiphysics simulations performed using methods that work …

Design Of A Semi-Continuous Bio-Oil Upgradation Process Using Iron/Bone-Char Catalysts, Kelli Thomas

Graduate Theses & Non-Theses

• 07Bio-oil is a pyrolysis byproduct that consists of heavily oxygenated organic fractions with low caloric values. There are very few industrial-sized facilities that can process bio-oil into useful hydrocarbons comparable to petroleum products. With the increase in biochar production for remediation efforts and forest clean-up, there is a demand for portable, small-scale refineries that do not require extensive process and safety equipment to convert byproducts into usable fuels. Refining bio-oil via atmospheric hydrodeoxygenation (HDO), the removal of the oxygenated functional groups under an unpressurized hydrogenated atmosphere, results in the upgradation of the heavy hydrocarbons within the bio-oil. This process is …

Process Intensification For Carbon Sequestration By Resonant Vibratory Mixing, Amirhosein Riahi

Graduate Theses & Non-Theses

Due to the excessive consumption of fossil fuels, which leads to significant greenhouse gas emissions and rapid climate change, it is crucial to develop various Carbon Capture and Sequestration strategies. CO₂ sequestration in solid, porous adsorbents like low-cost biochar emerges as a promising method to achieve this goal. However, slow adsorption kinetics are one of the issues that limit the widespread use of biochar. While the characteristics of biochar are important and impact CO₂ adsorption, the conditions under which adsorption occurs are equally critical.

In this work, a novel process intensification strategy, namely Low-Frequency High Amplitude resonant vibratory …

Stability, Mechanical Properties, And High-Pressure Structural Modifications Of Some Industrially Relevant Metallic Glasses, Alexander George

Graduate Theses & Non-Theses

Metallic glasses are metal-based alloys that have an amorphous structure and glass transition behavior as a result of being cooled rapidly enough to suppress crystal nucleation and growth[1]. Metallic glasses have been formed with two to eight constituents[2][3][4]; however, the most stable glass-forming systems typically contain four or more elements. With few exceptions, metallic glass-forming alloys are extremely unstable, requiring cooling rates on the order of 10⁸-10^-2 K/s to form a glassy sample. This instability translates to reheating, where onset crystallization temperatures infrequently exceed the glass transition by more than 100K. Strong glass-forming ability typically occurs over …

Mechanical Characterization Of Polymer Composites Embedded With Aramid Nanofiber, Evan Griffiths

Graduate Theses & Non-Theses

Self-healing materials are repairable and extend product lifetimes but are limited in application due to their mechanical properties such as low yield strength. Here, the mechanical properties of an elastomeric polymer composite containing aramid nanofiber are examined. These studies provided an economically feasible foundation to understand the doping concentration and resultant mechanical properties that would result should aramid nanofibers be used to reinforce a self-healing polymer that requires complex synthesis methods and expensive reactants. The elastomeric polymer used was polycaprolactone containing various weight percent aramid nanofiber. Quasi-static mechanical testing of these samples was performed following ASTM standardized tests for tension, …

Solar Process Heat Pyrolysis, Maxwell Triepke

Graduate Theses & Non-Theses

Solar process heat pyrolysis mobilizes the production of biochar via selective solar absorbance. Mobilization allows for the production of pyrolysis products at the location of the biomass source while eliminating the need for infrastructural power to operate the reactor. Traditionally, the implementation of economies of scale has led to large, permanent biochar production facilities; however, biochar feedstock is often in remote locations or stockpiled temporarily in mill/forestry operation locations. Modular reactors are important to eliminate feedstock location, transportation, and variability limitations. Previous work at Montana Technological University’s CHAR Laboratory has developed two lab scale modular, both tethered to infrastructural power. …

A Methodology For Evaluating And Comparing Unmanned Inspection Platforms In Underground And Indoor Environments, Sydney Shockley

Graduate Theses & Non-Theses

This report summarizes a research project focused on development of a methodology for evaluating the performance of various unmanned aerial vehicles (UAVs, commonly referred to as drones) and robotic platforms in GPS-denied environments, highlighting a clear stratification based on technological sophistication and design intent. A series of flight trials were designed and implemented in various environments including indoor spaces with various geometries and obstacles, and an underground mine. These trials examined signal range from the unmanned platform to the controller, the ability to navigate through confined spaces and obstacles, the overall ease-of-use and responsiveness of controls, as well as specialized …

Computational Fluid Dynamics Modeling Of 12.25” Horizontal Wellbores To Identify The Effects Of Pipe Rotation On Cuttings Transport Efficiency, David Rathgeber

Graduate Theses & Non-Theses

As global demand for oil and gas continues to rise alongside pressures to curb climate change, Exploration and Production (E&P) companies look to reduce their surface footprint and increase drilling efficiency through longer horizontal well drilling. In addition, the depletion of conventional reservoirs is causing E&P companies to target more difficult reservoirs, often miles offshore (Gupta et al., 2014; Meader et al., 2000a). The increased horizontal reach of these wells often leads to increased challenges in adequate hole cleaning during drilling operations. Efficient hole cleaning becomes a greater challenge in high-angle wells, with gravitational forces causing pipe eccentricity, flow channeling, …

Investigating The Production Of Af96 Steel Alloy By Additive Manufacturing Using Dry Metal Alloying, John Paul Osabutey

Graduate Theses & Non-Theses

The design of new alloys specifically for metal additive manufacturing (AM) is an emerging field of research. At present, metal AM primarily utilizes pre-alloyed powders, which are costly and lack flexibility in varying chemical compositions. This study outlines the adaptation of rapid alloy development in laser powder bed fusion (L-PBF) using elemental and ferro-alloyed powder blends. This method enables a more agile and resource-efficient approach to designing and screening new alloys, allowing for the swift generation of alloys with diverse chemical compositions. This thesis investigates the development of AF96 steel alloy through the innovative approach of mixing different elemental powders, …

Subspace Decomposition Of Linear Secrecy Codes, David Robert Joseph Hunn

Theses and Dissertations

We introduce a new method for the study of linear codes, termed subspace decomposition, which provides new insights into code structure and performance. Briefly, subspace decomposition comprises the evaluation of complex properties of a linear code by evaluating simple properties of its constituent subspaces. We find that this technique has application to a number of problems in coding theory. When applied to the problem of evaluating the performance of secrecy codes, subspace decomposition provides an efficient method for computing the equivocation of coset codes over the binary erasure wiretap channel. It is also especially efficient in computing the chi squared …

Development And Structural Origin Of Stretchable Semiconducting Polymers And Composites, Yunfei Wang

Dissertations

Stretchable semiconductors are pivotal in advancing wearable and implantable electronics, with those boasting both high stretchability and self-healing capabilities being especially significant for a myriad of wearable applications. In this dissertation, we developed an extremely soft, highly stretchable, and self-healing elastomer based on H-bonding crosslinked amide-functionalized polyisobutylene (PIB-amide). When blended with a high-performance conjugated diketopyrrolopyrrole (DPP-T) polymer, the composite exhibits unprecedented stretchability, exceptionally low elastic modulus, and an innate ability to self-heal at room temperature.

The morphology of conjugated polymer/elastomer semiconducting composites have significant impacts on electrical and mechanical properties Further investigations focused on manipulating the phase separation size in …

Localized Hermite Method Of Approximate Particular Solutions, Kwesi Acheampong

Dissertations

A localized Hermite method of approximate particular solutions (LHMAPS) is presented in this dissertation. This method is designed to improve the accuracy of the localized method of approximate particular solutions (LMAPS) for solving partial differential equations. LMAPS is a strong-form method that defines local radial basis function approximations to the solution values at a group of collocation points before applying the differential operator to this approximation function. Based on the LMAPS's local scheme, LHMAPS seeks Hermite-type local approximations based on both function values and derivatives. Numerical experiments validate the superior accuracy of the proposed method to the LMAPS by solving …