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Investigation Of Biofilm Formation And Osmotic Stress Tolerance Of Nonmotile Escherichia Coli In Simulated Microgravity, Tyler Jenkins Aug 2026

Investigation Of Biofilm Formation And Osmotic Stress Tolerance Of Nonmotile Escherichia Coli In Simulated Microgravity, Tyler Jenkins

Discovery Day - Daytona Beach

Simulated microgravity presents multiple physiological stressors for astronauts, including bone demineralization, muscle loss, and weakening of the immune system. Bacteria serve as viable model organisms to study physiological changes because of their abundance in the human digestive system and skin. Motility in bacteria plays a significant role in cell survival, but few studies have been conducted on microgravity’s effect on motility phenotypes. While motile strains like Escherichia coli K12 have been studied extensively under microgravity conditions, the effects of simulated microgravity on non-motile strains are largely unknown. To better understand this relationship, the nonmotile E. coli MG1655 strain was inoculated …


Multi-Dimensional Particle-In-Cell With Monte Carlo Collisions (Pic-Mcc) Simulation For Visualizing Plasma Flow And Secondary Ionization In Constricted-Anode Geometries, Parth Thakar Aug 2026

Multi-Dimensional Particle-In-Cell With Monte Carlo Collisions (Pic-Mcc) Simulation For Visualizing Plasma Flow And Secondary Ionization In Constricted-Anode Geometries, Parth Thakar

Discovery Day - Daytona Beach

Constricted-anode plasma sources generate locally intensified electric fields that enhance ionization near the anode, making them valuable in propulsion and laboratory plasma systems. However, the narrow geometry produces complex charge accumulation and secondary ionization effects that remain difficult to measure experimentally. To address this challenge, our research develops and applies a multi-dimensional Particle-in-Cell with Monte Carlo Collisions (PIC-MCC) simulation of a DC discharge in 1-D, 2-D, and 3-D configurations that model a constricted-anode device. PIC-MCC is a first-principles method that tracks electrons and ions individually while computing self-consistent electric fields and incorporating energy-dependent collision processes. This approach enables direct visualization …


Intensification Of Thermal Energy Storage Systems Based On Sodium Nitrate, Hari Suthan V Mr Aug 2026

Intensification Of Thermal Energy Storage Systems Based On Sodium Nitrate, Hari Suthan V Mr

Theses and Dissertations

Thermal energy storage (TES) systems employing phase change materials (PCM) bridge the gap between thermal energy demand and supply. The low thermal conductivity of sodium nitrate (NaNO3), an inorganic PCM for high-temperature TES systems restricts charging and discharging kinetics, reducing system-level performance. This thesis investigates the intensification of sodium nitrate-based thermal energy storage systems through the incorporation of different classes of additives. Metal oxides (zinc oxide and aluminium oxide) and carbon-based materials (graphene oxide (GO) and expanded graphite (EG)), were incorporated into NaNO3 to improve its thermophysical properties (thermal conductivity, latent heat, specific heat).

Composites were prepared using low-energy ball …


C.S.A. Assessment - Tamp Family Health Center Portal, Delante Clark Aug 2026

C.S.A. Assessment - Tamp Family Health Center Portal, Delante Clark

Graduate Scholarship and Creative Works

This C.A.S. assessment evaluates how the Tampa Family Health Centers website influences userattention, cognitive processing, information accessibility, navigation efficiency, and digital user experience.The assessment examines whether the platform supports intentional engagement and informed decision-making while minimizing cognitive overload, distraction, confusion, and unnecessary attentional demands.

TFHC serves as a healthcare access portal providing appointment scheduling, patient resources, providerinformation, healthcare services, MyChart access, payment services, and community health resources.These functions make attention management and information clarity critical to successful user outcomes.


Comparing Principal Component Analysis And Sequential Fusion Deeponet With Varying Dataset Size For Design Space Exploration Of Hypersonic Flow, J. Dallan Trentman Aug 2026

Comparing Principal Component Analysis And Sequential Fusion Deeponet With Varying Dataset Size For Design Space Exploration Of Hypersonic Flow, J. Dallan Trentman

Theses and Dissertations

Design space exploration and optimization of hypersonic vehicles is costly due to the difficulty of producing high fidelity CFD simulations in the hypersonic domain. Reduced order modeling can allow for design optimization at a fraction of the computational cost. This paper investigates the amount of training data required to produce an accurate Reduced Order Model. A PCA based ROM is developed and compared to a Sequential Fusion DeepONet by comparing model prediction accuracy, training time, and prediction time, across dataset sizes from 25 samples to 1024 samples. These models are applied to 2D hypersonic CFD simulations of the Orion reentry …


Resonant Shock Plate Simulation And Prediction Using Modal Substructuring, Harrison C. Denning Aug 2026

Resonant Shock Plate Simulation And Prediction Using Modal Substructuring, Harrison C. Denning

Theses and Dissertations

Aerospace structures such as rockets can experience various shock events during flight, such as stage separation or impacts. These shock events can expose components inside the rocket to large accelerations and stresses which in turn can damage the parts. Shocks are often simulated in the lab using a resonant shock plate test. Resonant shock plate testing is often used to qualify aerospace parts, as it can mimic the shocks experienced during launch and stage separations. However, during the course of development, both the definition of the shock environment and the design of the subcomponent tend to change, so that multiple …


Rfsoc Based Ground Penetrating Radar For Detection And Avoidance Of Underground Utilities, Brady Bowerbank Aug 2026

Rfsoc Based Ground Penetrating Radar For Detection And Avoidance Of Underground Utilities, Brady Bowerbank

Theses and Dissertations

Preexisting underground utilities present a considerable danger to underground boring projects. Gas and electrical lines can be damaged, leading to major economic impact and even loss of life. While maps of underground utilities exist, they are not always accurate and gas and electrical lines can shift over time, necessitating tools to accurately detect utilities so that crews can steer the machines away from any possible danger. In this thesis, the design of a new frequency-modulated continuous-wave (FMCW) ground penetrating radar (GPR) is outlined. The design of a lightweight, flexible radar is demonstrated using the CASPER FPGA framework with an operating …


Isoperimetric Soft Robots, Mihai Stanciu Aug 2026

Isoperimetric Soft Robots, Mihai Stanciu

Theses and Dissertations

This thesis presents two advances in isoperimetric soft robotic trusses that improve their performance, modularity, and configurability. The first contribution introduces a large-scale modular robotic truss designed as a lightweight, reconfigurable structure for lunar applications. The system consists of inflatable fabric tubes routed through motorized roller units and interconnected by a newly developed spherical joint that enables multiple robotic triangles to connect at a common vertex. The resulting truss can be assembled into structures beyond a single octahedron while retaining compact stowage when deflated and untethered operation after initial inflation. Experimental validation demonstrates modular assembly, long-term pressure retention, load-bearing capabilities …


Thermophysical Property Studies: 1. Thermodynamic Consistency For Associating Compounds 2. Autoignition Temperature, Cassandra Jane Guffey Aug 2026

Thermophysical Property Studies: 1. Thermodynamic Consistency For Associating Compounds 2. Autoignition Temperature, Cassandra Jane Guffey

Theses and Dissertations

Accurate thermophysical property data are essential for the design, optimization, and safe operation of chemical processes. Properties such as vapor pressure, enthalpy of vaporization, heat capacity, density, and autoignition temperature--which are among the properties studied in this work--are required for equipment sizing, process simulation, hazard assessment, and economic evaluation. A major focus of this dissertation is the application of multi-property thermodynamic consistency techniques to compounds that exhibit strong vapor-phase association. These methods improve confidence in recommended property values by enforcing rigorous thermodynamic relationships among ideal-gas heat capacity, liquid heat capacity, vapor and liquid densities, vapor pressure, and enthalpy of vaporization. …


From Homogeneous To Heterogeneous Adaptive Bounded-Confidence Opinion Dynamics On Networks, Sally Hafez, Fatma R. Farag, Amira S. N. Tawadros Aug 2026

From Homogeneous To Heterogeneous Adaptive Bounded-Confidence Opinion Dynamics On Networks, Sally Hafez, Fatma R. Farag, Amira S. N. Tawadros

Northeast Journal of Complex Systems (NEJCS)

Adaptive bounded-confidence models (ABCMs) elucidate the coevolution of agent states and network structure via local interactions and rewiring mechanisms. Traditional formulations assume uniform interaction parameters, leading to distinct regime shifts encompassing fragmentation, polarization, and consensus. A symmetric heterogeneous extension of the adaptive bounded-confidence model is introduced, in which interaction parameters vary according to whether agents belong to the same or different groups. The model retains the original update and rewiring protocols but integrates within-group and between-group confidence bounds alongside tolerance thresholds. Initially, the classic homogeneous model is replicated to establish a reference point. Subsequently, the heterogeneous extension is assessed under …


Reframing Soil Freezing As An Unsaturated Process, Antai Dong, Xiong Zhang Aug 2026

Reframing Soil Freezing As An Unsaturated Process, Antai Dong, Xiong Zhang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Soil freezing and frost heave are inherently unsaturated soil phenomena. However, most existing numerical models are based on saturated soil mechanics or assume full saturation. This simplification introduces conceptual inconsistencies, requires modifications that violate fundamentals in soil mechanics and fluid mechanics, and often leads to the use of self-conflicting soil properties. To overcome these limitations, this study develops a physically consistent, fully coupled thermohydraulic model for soil freezing grounded in modern unsaturated soil mechanics. A soil freezing characteristic surface (SFCS) is introduced to represent unfrozen water content in partially frozen soils as a function of both suction and temperature. Recognizing …


Advancing Internationalization With Collaborative Online International Learning (Coil): A Systems Engineering Approach, Sharon Bommer, Olumuyiwa Asaolu, Paul Dagnall, Scott Segalewitz, Oluwatoyin Popoola, Esther Adeyemi Aug 2026

Advancing Internationalization With Collaborative Online International Learning (Coil): A Systems Engineering Approach, Sharon Bommer, Olumuyiwa Asaolu, Paul Dagnall, Scott Segalewitz, Oluwatoyin Popoola, Esther Adeyemi

Journal of International Engineering Education

As globalization accelerates and engineering careers increasingly require international collaboration, engineering education programs must design courses and curricula to adequately prepare students for careers as engineers in modern industry. Collaborative Online International Learning (COIL) is a model of teaching and learning that supports the development of intercultural competence through a joint online learning environment. This paper presents a systems engineering approach of module development for an integrated COIL undergraduate course between a university in the United States and a university in Nigeria. The key objectives of this course are to increase students’ intercultural competence and to simulate global engineering management …


The Aggregation Of Microplastics By Enhancing Extracellular Polymeric Substance Production In Pseudoalteromonas Sp. Ncimb 2021 To Improve Removal Efficiencies In Environmental Matrices, Janelle L. Mercer Aug 2026

The Aggregation Of Microplastics By Enhancing Extracellular Polymeric Substance Production In Pseudoalteromonas Sp. Ncimb 2021 To Improve Removal Efficiencies In Environmental Matrices, Janelle L. Mercer

All Theses

Microplastics (MP) are ubiquitous in the natural environment and are a growing threat due to their small size and durability. Plastics are released into the environment through improper waste management, wastewater treatment outfalls, industrial spills, agricultural runoff, and landfills. These particles breakdown into secondary MP through degradation pathways. MP, less than 5 mm, require intricate removal techniques from water systems. Filtration techniques, though viable and effective, have implementation constraints due to high cost, maintenance demands, and filter fouling. By integrating coagulation and flocculation processes prior to filtration, MP removal efficiencies can increase, while minimizing operational challenges during filtration. Extracellular polymeric …


Evaluating The Potential For Chain Elongation To Produce Medium Chain Carboxylates From Anaerobic Conversion Of Lipids, Erin Boyer Aug 2026

Evaluating The Potential For Chain Elongation To Produce Medium Chain Carboxylates From Anaerobic Conversion Of Lipids, Erin Boyer

All Theses

Medium Chain Carboxylates (MCCs), including caproate and caprylate, are valuable chemicals in various industries that can be produced biologically through an identified chain elongation pathway called reverse β-oxidation. During lipid degradation in anaerobic co-digesters at wastewater treatment plants, methane production is maximized to ensure the successful breakdown of the lipids. It remains unclear whether the anaerobic conversion of lipids possesses the potential to produce MCCs, and this study sought to evaluate the potential using anaerobic co-digester sludge from a full-scale wastewater treatment plant. Batch assays were conducted using the sludge from the plant as inoculum, as well as palmitic acid, …


Building Services Engineering July/August 2026 Aug 2026

Building Services Engineering July/August 2026

Building Services Engineering

This issue of Building Services Engineering features heat pumps, propane usage, solar power, and ventilation for indoor air quality. Features include district heating, HVACR optimisation, lift retrofitting, EU water policy, and an interview with WiBSE Ireland Chair Heather Holt.


Human-Centered Design Of Extended Reality For Learning Adoption, Effectiveness, And Collaborative Training Performance, Bhargav Upadhyay Aug 2026

Human-Centered Design Of Extended Reality For Learning Adoption, Effectiveness, And Collaborative Training Performance, Bhargav Upadhyay

All Dissertations

Extended reality (XR) technologies like virtual reality (VR) and augmented reality (AR) can be used for technical training to help students learn and practice complex tasks in a safe digital environment. Despite known benefits evidence is required to explore the effectiveness of these technologies to support student learning outcomes. Furthermore, technical training programs need evidence about when these tools improve learning, what are the barriers to adoption of these technologies, and how training should be designed by leveraging these technologies. This dissertation examined how XR technologies can support higher education and workforce training, specifically focusing on barriers and facilitators to …


Can Kinematics Specify Tool Use Affordances?, Tyler Duffrin Aug 2026

Can Kinematics Specify Tool Use Affordances?, Tyler Duffrin

All Dissertations

Object properties such as length, shape, and heaviness, as well as affordance-based properties such as strike-with-ability and poke-with-ability, can be perceived via dynamic touch as functions of inertia tensor invariants. The primary question addressed here was whether people can perceive these same power and precision properties for purely virtual objects, which lack dynamic physical forces. The Kinematic Specification of Dynamics (KSD) principle asserts that missing dynamics are lawfully specified by kinematic (visual) motion patterns, such that kinematic information alone may support successful interactions with virtual objects. In three experiments, we investigated (1) whether virtual reality (VR) users could calibrate to …


Efficient And Scalable Visual Computing For Nanoscale Imaging, Hao Wang Aug 2026

Efficient And Scalable Visual Computing For Nanoscale Imaging, Hao Wang

All Dissertations

Nanoscale analysis often relies on instrument-mediated scientific imaging methods to capture visual signals that are difficult to observe, interpret, or quantify through ordinary perception alone. These domains are often characterized by low signal quality, limited annotations, complex morphology, non-natural visual statistics, and strong dependence on physical acquisition processes. This dissertation focuses on efficient visual computing for nanoscale imaging, with an emphasis on the representation, reconstruction, and analysis of high-resolution scientific visual data. In our early work, we relied on rule-based algorithms and conventional machine learning methods for feature extraction. However, these approaches struggle to scale with the increasing complexity and …


Color-Coding: An Aid Or Hindrance In A Multi-Unmanned Aerial Vehicle Supervisory Control Task, Austin Daniel Wood Aug 2026

Color-Coding: An Aid Or Hindrance In A Multi-Unmanned Aerial Vehicle Supervisory Control Task, Austin Daniel Wood

Theses and Dissertations

The purpose of the current study was to investigate the effect of coding types (i.e., alphanumeric coding, color-coding, and redundant color + alphanumeric coding) for vehicle identification and status information on pilots’ recognition performance, situational awareness (SA), and workload for a multi-vehicle operations ground control station (GCS) supervisory control task. With the aviation industry's push towards operators supervising and controlling multiple vehicles, it is pertinent to identify design features that support the capabilities and limitations of human operators. The current study employed a within-subjects, repeated-measures experimental design, in which a sample of 33 students with aviation experience performed three trials, …


Predicting Student Belonging In Computing Education: A Multimodal Machine Learning Approach Using Eeg And Survey Data, Hannah Moshtaghi Aug 2026

Predicting Student Belonging In Computing Education: A Multimodal Machine Learning Approach Using Eeg And Survey Data, Hannah Moshtaghi

Master's Theses

Measuring students’ sense of belonging, characterized by feelings of acceptance, inclusion, and encouragement from teachers, remains a significant challenge in computing education. Prior research has associated this multidimensional construct with positive academic outcomes and has identified instructors’ growth- and fixed-mindset messaging as a potential influence. However, belonging is a complex and deeply personal experience that is difficult to capture through direct observation alone. Current measurement methods rely on self-report surveys, which may not capture every aspect of an experience that can also involve emotional and cognitive responses.

This thesis investigates whether combining EEG data recorded during a belonging questionnaire with …


Isolation, Identification, And Enzymatic Screening Of Fungi From Utah Dryland Soils For Industrial And Waste Valorization Applications, Jessica Lorena Silva Cuero Aug 2026

Isolation, Identification, And Enzymatic Screening Of Fungi From Utah Dryland Soils For Industrial And Waste Valorization Applications, Jessica Lorena Silva Cuero

All Graduate Reports and Creative Projects, Fall 2023 to Present

Agricultural waste accumulation presents environmental challenges but also opportunities for biological valorization into value-added products. Fungi are particularly well-suited for this purpose due to their capacity to produce extracellular enzymes involved in the degradation of complex organic substrates. Dryland ecosystems represent a promising source for bioprospecting microbes capable of producing such enzymes. Drylands harbor a high diversity of extremophilic microorganisms that can withstand harsh conditions, extreme heat, UV, and low nutrients using unique adaptations. This suggests that these microbes are resilient and capable of surviving under varying conditions and still produce enzymes for biotransformation. The objective of this study was …


The Impact Of Early Exposure To Engineering Concepts In The Form Of Family, School Classes, And Stem Extracurriculars On The Long-Term Sense Of Belonging In Undergraduate Women In Engineering, Hannah Lloyd Aug 2026

The Impact Of Early Exposure To Engineering Concepts In The Form Of Family, School Classes, And Stem Extracurriculars On The Long-Term Sense Of Belonging In Undergraduate Women In Engineering, Hannah Lloyd

All Graduate Theses and Dissertations, Fall 2023 to Present

Engineering continues to struggle with the underrepresentation of women, and many women who begin engineering programs report feeling isolated or uncertain about whether they belong. A strong sense of belonging has been linked to greater confidence, persistence, and success in engineering. This study examined how early experiences with engineering before college may influence students' sense of belonging later in their undergraduate engineering programs.

Using survey responses from undergraduate engineering students across the United States, this study explored several types of early exposure to engineering, including family influence, school-based engineering and STEM courses, extracurricular programs such as robotics clubs and engineering …


A Cfd-Dem Framework For Characterizing Nanoparticle Adhesion Effects On Creeping-Flow Permeability In Composite Manufacturing, Gavin Stoker Aug 2026

A Cfd-Dem Framework For Characterizing Nanoparticle Adhesion Effects On Creeping-Flow Permeability In Composite Manufacturing, Gavin Stoker

All Graduate Theses and Dissertations, Fall 2023 to Present

Modern aircraft, spacecraft, and high-performance vehicles are increasingly built from composite materials, engineered combinations of plastics and fibers that are lighter and stronger than traditional metals. Researchers are now pushing these materials further by mixing in microscopic particles thousands of times smaller than a human hair, called nanoparticles, to make them even tougher and more resistant to damage. The challenge is getting those nanoparticles distributed evenly. During manufacturing, liquid plastic resin is pumped through a network of tightly packed fibers, carrying the nanoparticles along with it. But nanoparticles tend to clump together and stick to surfaces as they travel, clogging …


Cadmium Biosorption By Fusarium Venenatum And Its Application In Functional Permeable Materials For Metal Removal, Bradley Lawson Aug 2026

Cadmium Biosorption By Fusarium Venenatum And Its Application In Functional Permeable Materials For Metal Removal, Bradley Lawson

All Graduate Theses and Dissertations, Fall 2023 to Present

Heavy metals are pollutants of increasing concern as continued industrialization and urbanization have escalated the discharge of these toxins into aquatic environments. Cadmium (Cd) is a metal of particular concern due to its acute toxicity and high mobility in aquatic ecosystems. Given these characteristics Cd poses significant health risks to both humans and aquatic ecosystems. The continued development of sustainable, low-cost remediation technology is imperative to manage metal pollution.

This research explores the use of fungal-based remediation systems to remove Cd from contaminated water. Living biomass of the filamentous fungus Fusarium venenatum was evaluated as a biosorbent material for Cd …


Evaluation Of Ostomy Pouching Change Practices Among Hospital-Based And Community-Based Nurses, Hannah Gerlach Aug 2026

Evaluation Of Ostomy Pouching Change Practices Among Hospital-Based And Community-Based Nurses, Hannah Gerlach

All Theses

An estimated 725,000 to 1 million Americans are living with an ostomy and depend on ostomy pouching systems as part of their daily care. Effective ostomy management requires regular pouch changes and consistent skin care to prevent peristomal skin complications. Many individuals living with an ostomy face long-term challenges in managing their ostomy care, which can negatively affect their health-related quality of life. There is a need to understand how professional experience across different care environments, such as hospital-based and community-based settings, influences ostomy nursing care practices.

This study evaluates how nurses working in hospital-based settings and community-based settings perform …


Electrokinetic Flow Instabilities In Non-Newtonian Fluids With Conductivity Gradients, Md Mainul Islam Aug 2026

Electrokinetic Flow Instabilities In Non-Newtonian Fluids With Conductivity Gradients, Md Mainul Islam

All Theses

Electrokinetic instabilities (EKI) arise in electrically driven flows because the applied electric field interacts with spatial variations in electrical conductivity, generating electric body forces that can destabilize fluid interfaces. EKI can be beneficial by enhancing mixing in microchannels where diffusion is slow, but it can also be detrimental by disrupting stable sample transport, focusing, and separation. EKI has been widely studied in Newtonian fluids, and the electric Rayleigh number is known to govern the onset of this instability. However, very few studies have examined its behavior in non-Newtonian fluids, despite their prevalence in biological, chemical, and industrial applications. 

This thesis …


Drones In Wildfire Airspace Management: Developing A Scalable Framework For Mid-Sized Cities, Victoria Denise Tanner Williamson Aug 2026

Drones In Wildfire Airspace Management: Developing A Scalable Framework For Mid-Sized Cities, Victoria Denise Tanner Williamson

Engineering Management & Systems Engineering Theses & Dissertations

Wildfires are becoming increasingly frequent and severe, creating growing risks for mid-sized communities with limited emergency response resources. The January 2025 Los Angeles wildfires—which burned more than 57,000 acres and destroyed over 18,000 structures—underscore the urgent need to strengthen wildfire response strategies through the integration of unmanned aerial systems (UAS) (Hardy, 2025).

This study develops a scalable framework for drone-assisted wildfire response in resource-constrained environments. Using the city of Waynesboro, Virginia, as a case study, the research examines how mid-sized jurisdictions can integrate unmanned aerial vehicles (UAVs) to improve preparedness, response, and recovery. A three-round, mixed-methods Delphi study engages emergency …


Enhancing Stem Education With Modeling, Simulation, And Ai Technologies: From Virtual Laboratories To Intelligent Teaching Assistants, Yiyang Li Aug 2026

Enhancing Stem Education With Modeling, Simulation, And Ai Technologies: From Virtual Laboratories To Intelligent Teaching Assistants, Yiyang Li

Electrical & Computer Engineering Theses & Dissertations

Rapid advancements in modeling and simulation (M&S) and artificial intelligence (AI) present new opportunities to enhance various aspects of STEM education, from virtual laboratories that simulate physical lab environments in software to intelligent teaching assistants that provide on-demand, curriculum-aligned instructional support. Virtual laboratories offer a potential solution to the access and scalability challenges of laboratory courses by allowing students to conduct experiments without physical equipment or geographical constraints. AI-powered teaching assistants, particularly those grounded in course-specific materials, can help mitigate the instructional support gap that arises when students work independently in digital learning environments. This dissertation presents three-phase research into …


Experimental Investigation Of The Discharge Modes Of Nanosecond Pulsed Plasmas At Atmospheric Pressure, Md Ziaur Rahman Aug 2026

Experimental Investigation Of The Discharge Modes Of Nanosecond Pulsed Plasmas At Atmospheric Pressure, Md Ziaur Rahman

Electrical & Computer Engineering Theses & Dissertations

The generation of repeatable and stable nanosecond pulsed atmospheric pressure plasmas is important to non-thermal plasma applications in various fields including medicine, material processing, food processing, and plasma ignition for combustion. This dissertation investigates the atmospheric pressure plasma initiation and formation under 10 – 200 ns pulsed power for electrode configurations applicable for transient plasma ignition (TPI) for combustion. The impacts of pulsed power parameters, gas condition, and electrode geometry on the discharge initiation and modes (i.e., streamer, transient spark and spark) are systematically evaluated for applying TPI for combustion. We evaluated the discharge modes driven by both longer and …


Towards More Realistic And Practical Graph Backdoor Attacks, Jiawei Chen Aug 2026

Towards More Realistic And Practical Graph Backdoor Attacks, Jiawei Chen

Computer Science Theses & Dissertations

Graph Neural Networks (GNNs) have demonstrated remarkable performance on graph-based learning tasks and are increasingly deployed in security-critical applications. However, recent studies have shown that they are highly vulnerable to graph backdoor attacks (GBAs), where adversaries implant malicious triggers to induce targeted misclassification during inference. Despite their effectiveness, existing GBAs are often developed under unrealistic assumptions, such as focusing exclusively on simple homogeneous graphs or assuming the adversary possesses privileged access to target nodes during inference. This dissertation aims to systematically investigate and design graph backdoor attacks under significantly more realistic graph settings and adversarial constraints.

First, we investigate the …