La2nio4+Δ-Based Solid Oxide Electrolysis Cell (Soecs) Electrodes Enhanced With Complex Perovskite Nanocatalyst Processed By Surfactant-Enabled Infiltration, Cole Samuel Klemstine

Graduate Theses, Dissertations, and Problem Reports (ETD)

As the world seeks to reduce its reliance on hydrocarbons, the demand for sustainable hydrogen production methods has become increasingly critical. Hydrogen is a versatile energy carrier that can be produced from various sources, including water, natural gas, and biomass. Replacing the burning of hydrocarbons with hydrogen could significantly reduce greenhouse gas emissions, contributing to global climate goals like those set by the US H2NEW program. The joint technologies of solid oxide fuel and electrolysis cells present the ability to both produce and process clean hydrogen to meet these goals. Development into solid oxide fuel cells has been met with …

Customer Segmentation And Fuel Economy Prediction Using Telemetry Data From Heavy-Duty Trucks, Batishahe Selimi

Graduate Theses, Dissertations, and Problem Reports (ETD)

Heavy-duty trucks constitute only a modest fraction of on-road vehicles, yet their intensive duty cycles and high fuel demands yield a disproportionately large share of transportation fuel use and greenhouse gas emissions. Addressing this imbalance requires data-driven tools that capture the realities of fleet operation and translate complex telemetry into actionable insight.

This dissertation introduces a unified machine-learning framework that operates exclusively on high resolution time-series data collected from fifty-nine diesel trucks deployed across Southern California. It begins by constructing a multi-modal feature space that blends statistical summaries of key engine signals, static vehicle descriptors, and Mel-Frequency Cepstral Coefficients, thereby …

Modeling And Simulation Of Carbon-Neutral Strategies For Methanol Production, Omar Almaraz Barrios

Graduate Theses, Dissertations, and Problem Reports (ETD)

Methanol is a versatile chemical that can be used as a fuel, a solvent, a feedstock for other chemicals, and a hydrogen carrier. Methanol production from natural gas, which is mainly composed of methane, is a well-established process that involves steam reforming, methanol synthesis, and methanol purification. However, this process is energy-intensive and emits large amounts of carbon dioxide, which contributes to global warming and climate change. Therefore, there is a need for alternative methods of methanol production that are more efficient and environmentally friendly. The overall objective of this research is to develop simulation models of two novel methanol …

Finite Element Modeling And Experimental Characterization Of Overmolded Gold-Palladium Composite Leads And Their Mechanical Behavior Under Cyclic Fatigue For Long-Term Implant Applications, Tanner Davis

Graduate Theses, Dissertations, and Problem Reports (ETD)

Auditory Nerve Interface (ANI) devices, currently in developmental stages, represent an emerging neuroprosthetic approach to restore hearing in severe sensorineural loss patients by directly stimulating the auditory nerve via the Utah Slanted Electrode Array (USEA). Conventional implant leads are comprised of multiple wires made from materials such as platinum-iridium and MP35N stainless steel that are overmolded in an insulative material. These materials are not possible to bond with to electrode array used in the ANI device, necessitating the evaluation of a new material like Au-Pd to ensure its functionality and durability under cyclic stresses. This gap necessitates characterization of alternative …

Autonomous Vehicle Supported Mobility Services For Rural Areas, Alvira Ahmed Tasnim

Graduate Theses, Dissertations, and Problem Reports (ETD)

Autonomous Vehicles (AVs) are emerging as a promising mobility solution to address growing transportation demands, particularly unmet traffic demand in rural areas where conventional transit systems often fall short. Rural areas face unique mobility challenges due to dispersed populations, limited infrastructure, and low/no transit coverage. Existing transit services tend to concentrate around dense urban cores, leaving low-demand areas outside underserved. This spatial undercoverage leads to significant mobility gaps for rural residents. This study examines the potential of AV-based ride-sharing services to address these mobility needs by providing flexible, demand-responsive mobility services where fixed-route transit services are either economically or operationally …

Using Probabilistic Risk Assessment In Drilling R&D Projects, Jacob Matthew Smith

Graduate Theses, Dissertations, and Problem Reports (ETD)

Well drilling, since its inception, has always carried an intrinsic quantity of risk. Economically, the evolution of data analytics and the tools available to operators provide the opportunity to transform the lessons learned from previous well drilling endeavors into bottom line improvements. Additionally, methods for forecasting and risk management of potential trouble areas have significantly advanced due to the abundance of empirical data from prior drilling operations. Probabilistic Risk Assessment is a viable method through which risk can be tracked and mitigated in project management. Coupled with this data, the usage of Probabilistic Risk Assessment (PRA) provides a quantified, trackable …

Reactive Model-Free Control For Underactuated Vehicles Operating In Resource-Constrained Environments, Austin Lane Sponaugle

Graduate Theses, Dissertations, and Problem Reports (ETD)

Buoyancy-driven, underactuated vehicles offer a compelling solution for long-duration autonomous operations in constrained environments. By leveraging buoyancy to generate lift, these vehicles can remain aloft for extended periods with minimal power requirements, making them well-suited for applications in atmospheric monitoring, planetary exploration, and communications. However, their limited actuation authority, strong coupling with environmental forces, and operating domains introduce significant control challenges, including nonlinearity, sensitivity to external disturbances, and limited observability.

This work investigates the design and implementation of lightweight, reactive model-free control strategies that enable robust autonomy in such constrained settings. A digital Extremum Seeking Controller (ESC) is first implemented …

Comparative Analysis Of Electrode Encapsulation Reliability: Planar Vs. Thermoformed Interdigitated Neural Electrodes In Biomedical Engineering, Tatum Peyerl

Graduate Theses, Dissertations, and Problem Reports (ETD)

Durable dielectric encapsulation is crucial for the long-term function of implantable neural electrodes; however, the reliability of curved, thermoformed coatings remains underexplored. This study addresses that gap by comparing planar (non-thermoformed) and thermoformed interdigitated neural electrodes (IDEs) encapsulated in Polyimide-2611. Both device types underwent accelerated in vitro aging in phosphate‑buffered saline (PBS) at 67 °C for approximately 91 days, simulating two years of physiological exposure. Post-accelerated aging evaluation included electrochemical impedance spectroscopy (EIS) from 0.1 Hz to 100 kHz to monitor moisture‑induced leakage, and high‑voltage breakdown testing under saline immersion to assess dielectric strength. After aging, all electrodes maintained impedance …

Leveraging Physiological Signal Activity And Self-Report Data To Assess Students’ Trust In “My Friendly Mind” App And Its Impact On Their Mental Health Knowledge: A Mixed-Method Phase 1 Clinical Trial Focusing On Depression And Attention Deficit Hyperactivity Disorder From Human Factors Standpoint., Yeganeh Shahsavar

Graduate Theses, Dissertations, and Problem Reports (ETD)

Mental health issues have become a significant global public health concern, especially among younger generations. The growing number of mental health challenges, combined with limited access to quality care, makes the problem even worse. Studies reveal that over 70% of individuals worldwide in need of mental health services do not receive appropriate care. Digital health technologies have the potential to enhance mental health services by making them more accessible and affordable. Despite the increasing popularity of mental health mobile applications (mHealth), there remains a lack of robust evidence of their effectiveness and the level of user trust, particularly in areas …

Investigation Of Spalling Effects On The Brittle Behavior Of Rectangular Pillars In Underground Stone Mines, Yolver Yesid Jimenez Ibanez

Graduate Theses, Dissertations, and Problem Reports (ETD)

Recent catastrophic collapses in U.S. limestone mines have exposed the limitations of traditional empirical design formulas for brittle rock masses. These events, especially those involving slender pillars, underscore that traditional methods often fail to account for progressive, spalling-dominated failure, highlighting a crucial gap in our understanding. This research addresses this issue by conducting a comprehensive investigation into the mechanics of spalling in rectangular stone mine pillars, utilizing advanced three-dimensional numerical modeling with FLAC3D combined with LiDAR-based geometric modeling.

The stability of a pillar is governed by a complex interaction between the in-situ stress field, rock mass properties, and pillar geometry. …

Revitalizing The Urban Riverfront: Redesigning The West End Bridge In Pittsburgh,Pa For Sustainable Multi-Use Connectivity And Public Space Creation., Mina Kargari Rezapour

Graduate Theses, Dissertations, and Problem Reports (ETD)

Urban waterfronts are critical assets for cities, offering opportunities for ecological restoration, public engagement, and multi-modal transportation. However, many riverfronts remain underutilized due to infrastructure barriers and lack of accessibility.

Pittsburgh’s riverfront is dynamic asset that supports recreation, cultural expression, and community interaction. The Three River Heritage Trail Loop, a visionary project led by River Life over the past 20 years, seeks to connect diverse neighborhoods and natural assets along the city’s rivers. At the heart of this initiative is the West End Bridge, serving as the bookend and a pivotal gateway to complete the loop and critical link for …

Improving Large Scale Face Recognition With Identity Codes, Mohammad Saeed Ebrahimi Saadabadi

Graduate Theses, Dissertations, and Problem Reports (ETD)

Despite significant advances in deep face recognition, current systems face several practical challenges in real-world scenarios. These include high computational cost of training on large-scale datasets, inefficient use of metric space, and mismatch between training and evaluation frameworks. This dissertation addresses these limitations through three completed studies. The first part presents a research effort aimed at addressing the computational bottlenecks of large-scale FR training. This work proposes a framework that replaces conventional scalar identity labels with structured identity codes, \ie, sequences of tokens optimized to preserve semantic and metric separation. The formulation is designed to reduce the computational cost of …

Neural Network-Based Image Compression, Atefeh Khoshkhahtinat

Graduate Theses, Dissertations, and Problem Reports (ETD)

The rapid advancement of information technology and the exponential growth of digital communication have significantly increased the demand for efficient data compression techniques that reduce storage requirements, minimize bandwidth consumption, and accelerate data transmission—without substantially compromising data quality. This dissertation addresses these challenges by investigating and developing advanced learned image compression (LIC) methods, with a particular focus on lossy compression for both natural images and scientific imagery obtained from NASA’s Solar Dynamics Observatory (SDO) mission. Traditional image compression standards—such as JPEG, JPEG2000, BPG, and HEVC—rely on manually engineered transforms and heuristic rules, which often lack the adaptability required to accommodate …

Assessing And Predicting The Impact Of A Retrofitted Methane Mitigator On Non-Road Large Natural Gas Engines Using Artificial Neural Networks, Augustine Thomas Ojo

Graduate Theses, Dissertations, and Problem Reports (ETD)

Abstract

ASSESSING AND PREDICTING THE IMPACT OF A RETROFITTED METHANE MITIGATOR ON NON-ROAD LARGE NATURAL GAS ENGINES USING ARTIFICIAL NEURAL NETWORKS

Augustine Thomas Ojo

Methane emissions from the oil and gas sector present a pressing environmental and economic challenge, given methane’s high global warming potential and the considerable volumes of unutilized gas lost from industrial processes. This study investigates the impact of a retrofitted methane mitigation system, the Methane Mitigator (M²), on fuel consumption and engine-out emissions in non-road, four-stroke natural gas-powered, lean-burn engines and develops predictive Artificial Neural Network (ANN) models to estimate the resulting engine-out emissions and fuel …

Synthetic Data–Driven Early Prediction Framework For Acute Kidney Injury In Patients Receiving Vancomycin And Ceftazidime/Avibactam, Maryam Ramazani

Graduate Theses, Dissertations, and Problem Reports (ETD)

Background: The nephrotoxic risks of combining ceftazidime/avibactam (AVI) with vancomycin (VAN) remain underexplored, despite both agents independently being linked to acute kidney injury (AKI). This study assessed the risk of AKI associated with concurrent VAN and ceftazidime/avibactam (VAN-AVI) therapy and developed synthetic data models to enable early prediction of AKI.

Methods: We conducted a retrospective analysis using electronic health record data from hospitalized adults between 2015 and 2022. The incidence of AKI was compared among patients receiving VAN-AVI or VAN in combination with piperacillin/tazobactam (VAN-TPZ) versus VAN monotherapy. AKI was defined as a composite of de novo and recurrent AKI …

Parametric Analysis Of Proppant Selection Impact On The Hydraulic Fracture And Productivity Of Extended-Reach Marcellus Shale Wells, Nicholas Hunter Lapinski

Graduate Theses, Dissertations, and Problem Reports (ETD)

Hydraulic Fracture Proppant is the gateway to reservoir connectivity, allowing for decades of natural gas production from hydraulically fractured wells in the Marcellus Shale. The proper selection of proppant can have major ramifications on the productivity of the extended-reach Marcellus shale wells. The proppant penetration into the induced fracture attempts to close the gap between the realistic non-uniform fracture conductivity and the idealistic uniform fracture conductivity. Consequently, the more proppant residing within these fractures, the more likely the proppant is to resist crushing due to the compaction. Phenomena, Advancements have been made to create more durable proppant types or proppant …

Dynamic Force Feedback Controller Improves Metrics Of Stepping In A Biomimetic Robot Leg, Isabella Mae Kudyba

Graduate Theses, Dissertations, and Problem Reports (ETD)

Force feedback is a type of robotic control where forces are measured, fed back into the control system, and actuation is adjusted to compensate for environmental forces, with the goal of quick and precise limb positioning in walking. Robots of today use single force sensors (e.g. pressure sensitive pads, load cells) per leg which are often bulky, expensive, and susceptible to crosstalk. Walking robots often employ model predictive controllers or policy controllers trained through reinforcement learning (RL) to actuate their limbs, but these methods are time and energy consuming. Biomimetic robots offer an alternative approach, investigating biological theories with the …

The Impact Of Skew On The Flexural Behavior Of Press-Brake-Formed Tub Girders, Matthew Allan Weatherholt

Graduate Theses, Dissertations, and Problem Reports (ETD)

The Short Span Steel Bridge Alliance (SSSBA) is a group of bridge and buried soil steel structure industry leaders who have joined together to provide educational information on the design and construction of short span steel bridges in installations up to 140 feet in length. Press-brake-formed-tub-girders (PBFTGs) were developed by a technical working group within the SSSBA in response to a rising demand for rapid infrastructure replacements for short span bridge applications. PBFTGs are produced from structural steel plate and can be finished as weathering steel or galvanized. After being cold bent to the appropriate shape, shear studs are welded …

Fundamental And Applied Investigation Of Ammonia Combustion: Characteristics And Emissions At Relevant Ic Engine Conditions, Luis Fernando Alvarez Correa

Graduate Theses, Dissertations, and Problem Reports (ETD)

Ammonia (NH3) is regarded as a promising fuel for future carbon-free power and propulsion systems due to its high hydrogen content, ease of storage, and existing infrastructure. Despite these advantages, NH3 exhibits inherently poor combustion characteristics, including low laminar burning velocity, high ignition energy, narrow flammability limits, and sluggish chemical kinetics. These limitations were solved in prior research by blending NH3 with hydrogen (H2) or hydrocarbons, which improved reactivity but introduced trade-offs such as increased complexity, safety concerns, or carbon emissions. Consequently, there remains a significant lack of fundamental and applied research on neat NH3 combustion, particularly under engine-relevant conditions …

Replicating The Functionality Of Ghost Knifefish Cerebellar Feedback Using Synthetic Nervous Systems, Sheldon Paul Cj Johnson

Graduate Theses, Dissertations, and Problem Reports (ETD)

Sensory inputs allow animals to perceive, react, and adapt to an environment. However, the sensory information received by the body, such as visual, auditory, and proprioceptive information, could become overwhelming, thus overloading the brain. Yet, animals can process all this information by canceling redundant signals from their surroundings, allowing them to be more sensitive to novel or unexpected signals in their environment. Each species (i.e., birds, fish, mammals) has its own way of using and filtering sensory information, from auditory to locomotion adaptivity. Cerebellar circuits contribute to sensory filtering in a variety of systems. In particular, research on Ghost knifefish …

Characterization Of Properties And Defects Of Alternative Matrix Materials For 3d Printed Continuous Carbon Fiber Reinforced Composites, Noah Darren Osborne

Graduate Theses, Dissertations, and Problem Reports (ETD)

Additive manufacturing, commonly known as 3D printing, has the potential to transform the production of end-use parts by facilitating the creation of complex shaped, low-volume components that are expensive to manufacture using traditional methods. However, thermoplastic polymer matrices currently utilized in 3D printing of carbon fiber composites, often lack the mechanical properties needed for aerospace applications. To address this issue, researchers have developed fiber-reinforced 3D-printed composites using an innovative two-step process which involves printing 3D preforms using fused deposition modeling, followed by compression molding. However, most previous work involves the use of nylon-based polymer matrices while there are a number …

A Durability Evaluation Of Class B Concrete Bridge Substructures Under West Virginia Freeze–Thaw Conditions, Nathaniel Wayne Dunbar

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study evaluates whether the West Virginia Division of Highways (WVDOH) Class B concrete specification for bridge substructures remains adequate under modern durability and design-life expectations. The current specification, which permits a minimum compressive strength of 3,000 psi, reflects practices established when shorter service lives were generally assumed. Modern AASHTO LRFD provisions are based on a 75-year design life, raising concern that this lower-strength concrete may not provide sufficient durability under West Virginia’s climatic conditions.

To address this issue, bridge inspection data, regional climate mapping, and durability modeling were used to assess the condition and performance of concrete substructures across …

Parameter Estimation Of A 100 Seater Simulated Passenger Aircraft, Michael James Winston

Graduate Theses, Dissertations, and Problem Reports (ETD)

Virtual flight test aircraft provide good opportunities to test new parameter estimation methods. However, good estimates for the parameters in VIRTTAC Castor, a virtual test aircraft, are unavailable. This thesis uses two well-established time domain methods, the Output Error Method and the Filter Error Method, to estimate the parameters of VIRTTAC Castor. Three standard maneuvers were used: Elevator 3-2-1-1, Rudder Doublet, and Aileron Multi-Step. The parameters were estimated across three different flight conditions: weight, altitude and air speed, which resulted in 27 tests for each maneuver. All parameters, and standard deviations estimated are included in the appendix as a table.

Development Of A Model To Estimate Engine Crankcase Methane Vent Emission Rates, Juan Pablo Rincon

Graduate Theses, Dissertations, and Problem Reports (ETD)

The primary focus of this research is the modeling and validation of crankcase methane emissions stemming from natural gas combustion engines commonly deployed in the natural gas compression industry. The models employed rely on equations predicting the flow rate and composition of losses, typically generated within reciprocating piston-cylinder systems. Since crankcase emissions originate in a piston–cylinder arrangement, multiple variables were considered in this study, including displaced volume, pressure, temperature, flow, and viscosity (with corrections applied to account for the thermal and compositional effects on the mixture of fluids). The initial data for this research was collected during three measurement campaigns …

Watershed-Level Survey Of Antimicrobial Resistance From Onsite Wastewater Systems, Trey Franklin Clark

Graduate Theses, Dissertations, and Problem Reports (ETD)

The emergence of antimicrobial resistance (AMR) has quickly become one of the largest global health and development threats. Research related to environmental modes of transmission of AMR has accelerated in recent years, and the US Environmental Protection Agency is particularly interested in this emerging contaminant. Knowledge of how onsite (decentralized) wastewater treatment systems contribute to this issue is lacking, so this research serves to analyze and quantify the environmental dissemination of AMR and fecal contamination from these sources at a watershed level while using statistical analysis to assess relationships between physiochemical, spatial, and sampling parameters. This research surveyed four watersheds …

Analysis And Field Demonstration Of A Mobile Dewatering Cell For Acid Mine Drainage And Rare Earth Element Hydraulic Preconcentrate, Hunter David Vance

Graduate Theses, Dissertations, and Problem Reports (ETD)

A field scale mobile dewatering cell was constructed and demonstrated to investigate the filtration efficiency and dewatering characteristics of the cell. The cell was tested using hydraulic preconcentrate (HPC) from an active AMD treatment plant located in the Morgantown, WV area. HPC is a sludge-like material that comes from a two-stage treatment process of acid mine drainage, and it contains various rare earth elements. The cell was filled with HPC over time and the influent HPC and effluent water exiting the cell were tested each time the cell was filled. Taking these samples and other measurements, the filtration efficiency and …

Oxidation Behavior Of Silicon Carbide, Matrix Graphite, And Refractory Multi-Principal Element Alloy, Visharad Jalan

Doctoral Dissertations

"The present study focuses on the investigation of the oxidation behavior of silicon carbide, matrix graphite in a water vapor environment. It also examines the oxidation behavior of refractory multi-principal element alloys when exposed to air. The oxidation behavior of silicon carbide and matrix graphite were investigated in conditions pertaining to off-normal incidents in high-temperature gas-cooled nuclear reactors. Understanding this is crucial for the prediction of their performance in such accidents and ensuring that the nuclear reactor is accident tolerant. Upon exposure to water vapor, the two A3-based matrix graphite exhibited different behaviors. The A3-27 type showed oxidation in all …

Lifelong Machine Learning With Adaptive Resonance Theory, Sasha Petrenko

Doctoral Dissertations

"This publication option dissertation is composed of three papers concerning the study of the problem lifelong machine learning with Adaptive Resonance Theory (ART) algorithms. Lifelong learning (L2) is a challenging machine learning paradigm that both encompasses and formalizes the fields of continual learning and incremental learning. The field is concerned with the mitigation of the phenomenon of catastrophic forgetting whereby learning agents that are faced with incrementally novel information deleteriously overwrite previous knowledge if that learning process is not regularized to counteract this consequence. ART algorithms solve this stability-plasticity dilemma by optimally assigning learning to categories or instantiating new knowledge …

Metal-Organic Thin Film Coated On Optical Fiber, Nahideh Salehifar

Doctoral Dissertations

This dissertation explores the development of metal-organic framework (MOF)-based optical fiber sensors for detecting volatile organic compounds (VOCs) at low concentrations (parts-per-billion to parts-per-million). In the first part of the study, theoretical calculations were performed using effective medium approximation (EMA) models, including Lorentz–Lorentz, Maxwell–Garnett, and Bruggeman equations, to predict the refractive index changes of MOFs upon gas adsorption. These models were applied to MOFs such as ZIF-7, ZIF-8, ZIF-90, MIL-101(Cr), and HKUST-1 to evaluate their potential for gas sensing.

In the second part of the dissertation, experimental work was conducted to validate the theoretical predictions. MOF-coated optical fibers were fabricated …

Deep Learning Architecture Design For Nano-Satellite Image Super-Resolution, William Everette Symolon

Doctoral Dissertations

Increasing threats to U.S. national security satellite constellations have resulted in an increased interest in constellation resilience and satellite redundancy. NanoSats have contributed to commercial, scientific and government applications in remote sensing, communications, navigation, and research. They also have the potential to enhance satellite constellation resilience. However, the inherent size, weight, and power limitations of NanoSats enforce constraints on imaging hardware; the small lenses and short focal lengths result in imagery with low spatial resolution, which limits the utility of CubeSat images for military planning purposes and national intelligence applications. This research proposed a deep learning architecture capable of enhancing …