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Cross-Layer Supervisory Control For Low-Altitude Uav Swarm Networks, Nitin Singh Rathore Jan 2026

Cross-Layer Supervisory Control For Low-Altitude Uav Swarm Networks, Nitin Singh Rathore

Computer Science and Engineering Theses

Low-altitude unmanned aerial vehicle (UAV) swarms are increasingly used in applications such as aerial sensing, disaster response, and communication support, where reliable operation under dynamic and uncertain conditions is essential. In these environments, performance degradation arises from multiple sources, including external disturbances, sensing uncertainty, and communication impairments. Although these effects originate from different layers of the system, such as dynamics, observation, and networking, they often manifest as similar tracking or coordination errors. Conventional control approaches, which rely primarily on error-driven feedback, do not explicitly account for the underlying cause of these deviations, limiting their effectiveness in multi-agent settings. This thesis …


Effects Of Metals On Persulfate Activation For The Decomposition Of Pfas, Malu Deav Devadasan Jan 2026

Effects Of Metals On Persulfate Activation For The Decomposition Of Pfas, Malu Deav Devadasan

Civil Engineering Dissertations

Per- and polyfluoroalkyl substances (PFAS) are persistent environmental contaminants widely used in industrial and consumer products due to their unique physicochemical properties. Their resistance to degradation, potential for bioaccumulation, and associated adverse health effects have prompted increasing regulatory attention, including the establishment of drinking water standards for six PFAS compounds by the U.S. Environmental Protection Agency in 2024.

Current PFAS treatment technologies are often energy-intensive and costly or generate secondary waste streams requiring further management. Meanwhile, this research investigated transition metal-catalyzed advanced oxidation processes for PFAS decomposition in water under ambient conditions. Previous studies demonstrated effective degradation of perfluorocarboxylic acids …


Gaussian Process Regression–Based Uncertainty Quantification For Unmanned Aircraft System Traffic Management And Advanced Air Mobility Applications, Aakarshan Khanal Jan 2026

Gaussian Process Regression–Based Uncertainty Quantification For Unmanned Aircraft System Traffic Management And Advanced Air Mobility Applications, Aakarshan Khanal

Mechanical and Aerospace Engineering Dissertations

Uncertainty quantification has gained significant attention in recent years as a research area in dynamical systems. Mathematical representations of the physical system, combined with an understanding of model uncertainties, enable the propagation of uncertainty in temporal space, which allows us to make informed decisions. However, what if the true dynamics of the system is unknown or too complex to define explicitly? In such cases, the system’s behavior can instead be inferred or learned from observed input–output data rather than from an analytical or physics-based model. To this end, this dissertation focuses on developing a data-driven framework for nonparametric dynamics modeling, …


Anaerobic Digestion Of Food Waste Components: Modeling Biogas Production, Opeyemi E. Adelegan Jan 2026

Anaerobic Digestion Of Food Waste Components: Modeling Biogas Production, Opeyemi E. Adelegan

Civil Engineering Dissertations

Food waste constitutes the single largest component of municipal solid waste landfilled in the United States — approximately 22% of 292.4 million tons generated in 2018 — and its anaerobic decomposition releases methane, a greenhouse gas with global warming potential approximately 27–30 times that of carbon dioxide over a 100-year horizon (IPCC, 2021). Anaerobic digestion (AD) offers an alternative management pathway that recovers energy and produces nutrient-rich digestate, but AD performance varies by as much as five-fold across food waste streams (130–630 m3 CH4 per Mg VS added), and existing predictive tools either treat food waste as a …


Two-Phase Transcritical Carbon Dioxide Flow At The Microscale For Thermal Management Applications, Soroush Niazi Jan 2026

Two-Phase Transcritical Carbon Dioxide Flow At The Microscale For Thermal Management Applications, Soroush Niazi

Graduate Studies Theses and Dissertations 2026

High-power electronic and power-conversion devices now generate heat fluxes that exceed what conventional air- and single-phase-liquid cooling can dissipate, motivating the search for more capable coolants and cooling mechanisms. Carbon dioxide is an attractive candidate for this role: it is inexpensive, non-toxic, and environmentally friendly, and near its critical point its thermophysical properties change rapidly, which raises the heat-transfer coefficient. In addition, a large pressure drop produces strong cooling through the Joule–Thomson effect and phase change, so that the throttling element itself becomes a source of cooling. This dissertation studies the throttling, phase change, and choking of high-pressure carbon dioxide …


Beyond The Square Pulse: Waveform Shape, Eeg Correlates, And The Pursuit Of Natural Sensation In Tens, Jason Whitson Jan 2026

Beyond The Square Pulse: Waveform Shape, Eeg Correlates, And The Pursuit Of Natural Sensation In Tens, Jason Whitson

Honors Undergraduate Theses

This study investigates the relationship between electrical stimulus characteristics of shape and charge on evoked sensations and electroencephalogram (EEG) data during multi-waveform transcutaneous electrical nerve stimulation (TENS) of the median nerve. Neuromodulation methods have traditionally had little control over the location and quality of their associated evoked sensation (e.g., electric, vibration, touch). This experiment utilized five unique stimulus waveforms during TENS stimulation. EEG data were collected concurrently to provide an introductory objective measure of the neural responses underlying these sensory changes. Eleven participants completed three tasks (thresholding, super-threshold stimulation, two-alternative forced choice) using a two-electrode TENS approach. Stimulus waveforms were …


Artificial Intelligence In Cybersecurity: Applications, Threats, And Implications, Brandon A. Rodriguez Jan 2026

Artificial Intelligence In Cybersecurity: Applications, Threats, And Implications, Brandon A. Rodriguez

Honors Undergraduate Theses

The point of this thesis is to analyze the growth of artificial intelligence in the world of cyber security, highlighting the specific impacts it has in the use of defense and offensive misuse. The way that this research was done was by using three main methods, those being interviewing cybersecurity specialists, testing the uses of public AI models and by reviewing peer-reviewed studies. Some of the findings that were discovered with the research were that AI can be a great asset in supporting defensive systems with such things as assisting in the creation of scripts, but there are also negatives …


A Chicken Model For Non-Invasive Diagnosis Of Infant Developmental Dysplasia Of The Hip (Ddh) Using Acoustic Transmission Measurements, Aliza Shah Jan 2026

A Chicken Model For Non-Invasive Diagnosis Of Infant Developmental Dysplasia Of The Hip (Ddh) Using Acoustic Transmission Measurements, Aliza Shah

Honors Undergraduate Theses

Developmental dysplasia of the hip (DDH) is a condition characterized by abnormal development and stability of the hip joint. In a healthy infant, the femoral head (ball) fits securely within the acetabulum (socket of the pelvis), allowing for proper joint function. In DDH, the relationship is disrupted, ranging from mild acetabular dysplasia to partial (subluxation) or complete dislocation of the femoral head. This condition represents a range of structural abnormalities that develop during early growth. The integrity of the hip joint is essential for physical mobility, and disruption of this structure can lead to significant functional impairment. DDH may result …


Evaluating The Brain-Muscle Connectivity Of Cyclic Ankle Pedaling Movement In A Clinical Setting, Matthew K. Shanosky Jan 2026

Evaluating The Brain-Muscle Connectivity Of Cyclic Ankle Pedaling Movement In A Clinical Setting, Matthew K. Shanosky

Graduate Studies Theses and Dissertations 2026

Clinical neurorehabilitation requires objective biomarkers to accurately detect and monitor neuromotor impairments. While traditional metrics are favored for their efficiency and minimal equipment demands, they typically rely on subjective observation and lack physiological resolution. High-resolution electrophysiological technologies, such as electroencephalography (EEG) and electromyography (EMG), offer objective insights into nervous system dynamics; however, prolonged data acquisition times have hindered their translation into frontline clinics. To bridge this translational gap, this study developed a time-efficient experimental paradigm designed for rapid clinical deployment. Healthy participants completed two initial resting baseline trials before performing an externally paced, dynamic, cyclic ankle movement task utilizing simulation …


Feasibility Of Corn Stover For Biogas Production In Northwestern Illinois: A Case Study Of Jo Daviess And Carroll Counties, Anthony Amotoe-Bondzie Jan 2026

Feasibility Of Corn Stover For Biogas Production In Northwestern Illinois: A Case Study Of Jo Daviess And Carroll Counties, Anthony Amotoe-Bondzie

Masters Theses

The growing demand for renewable energy and sustainable waste management has intensified interest in agricultural residues such as bioenergy feedstocks. This study evaluated the feasibility of converting corn stover into biogas through anaerobic digestion (AD) in Jo Daviess and Carroll Counties, Illinois, with consideration of the Savanna Industrial Park as a potential centralized processing hub. Although corn stover represents one of the largest biomass resources in the United States, this research identifies a critical gap between theoretical availability and practically recoverable feedstock. Using a mixed-methods framework, the study integrates biomass quantification, methane yield modeling, economic analysis, and policy assessment. Results …


Lean Service System Optimization In U.S. Automotive Maintenance Centers: A Time Study And Simulation-Based Approach To Reducing Service Cycle Time And Increasing Efficiency, Rakibul Hasan Sarker Jan 2026

Lean Service System Optimization In U.S. Automotive Maintenance Centers: A Time Study And Simulation-Based Approach To Reducing Service Cycle Time And Increasing Efficiency, Rakibul Hasan Sarker

All Graduate Theses, Dissertations, and Other Capstone Projects

The primary objective of this study is to measure the current service time at a U.S. automobile service center, with the aim of reducing waste and optimizing service operations through time study and simulation modeling. Inefficiencies in those service centers increase service time and labor costs, reduce service quality, and reduce workshop productivity, thereby increasing customer waiting time. In this study, real-world shop floor data were collected from a single service center, namely Jiffy Lube. Over the course of ten working days, 205 vehicle data points were acquired. Service time, bay time, and overall process time were computed and examined …


Application Of Diatom Indices To Monitor Environmental Shifts In The Downstream Tuntang River, Central Java, Mirza Hanif Al Falah, Tri Retnaningsih Soeprobowati, Hadiyanto -, Muhammad Isnaini Ibnu Sabil, Marta Wojewódka-Przybył, Łukasz Kruszewski, Paweł Rydelek Jan 2026

Application Of Diatom Indices To Monitor Environmental Shifts In The Downstream Tuntang River, Central Java, Mirza Hanif Al Falah, Tri Retnaningsih Soeprobowati, Hadiyanto -, Muhammad Isnaini Ibnu Sabil, Marta Wojewódka-Przybył, Łukasz Kruszewski, Paweł Rydelek

Applied Environmental Research

Diatoms are widely recognized as sensitive bioindicators for reconstructing past water quality and ecological changes in aquatic ecosystems. In this study, multiple diatom-based indices were applied to sediment cores collected from three downstream stations of the Tuntang River, Central Java, to infer long-term environmental change in a tropical river system. A total of 38 sediment subsamples were analyzed, with dominant taxa including Fragilaria crotonensis (2.4–18.6%), Nitzschia palea (3.1–22.4%), and Aulacoseira granulata (2.0–15.8%), indicating sustained nutrient enrichment. Diatom indices consistently classified conditions as mesotrophic to eutrophic throughout the sediment profiles. The occurrence of the marine diatom Cylindrotheca closterium (up to 6.3%) …


Recycling Waste Polyethylene Terephthalate For Asphalt Modification: A Comprehensive Review On Material Properties, Processing Techniques, And Engineering Applications, Ruizhe Huang, Feng Ma, Ke Shi, Zhen Fu, Jenny Liu Jan 2026

Recycling Waste Polyethylene Terephthalate For Asphalt Modification: A Comprehensive Review On Material Properties, Processing Techniques, And Engineering Applications, Ruizhe Huang, Feng Ma, Ke Shi, Zhen Fu, Jenny Liu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Polyethylene terephthalate (PET) is a thermoplastic polyester widely used in beverage bottles and packaging materials, accounting for approximately 60% of global plastic production. Due to its non-biodegradable nature, the accumulation of waste PET has posed a serious environmental challenge worldwide. In recent years, the recycling of PET for use in road engineering has been considered an effective approach to promote resource circulation and reduce plastic pollution. This paper first reviews the main recycling methods of PET, including mechanical shredding and chemical depolymerization, and analyzes its molecular structure, thermal properties, and reprocessing adaptability. Two typical engineering application paths are then evaluated: …


Toward Neurosymbolic Reinforcement Learning Via Editable Specifications, Vedant Khandelwal, Hong Yung Yip, Amit Sheth Jan 2026

Toward Neurosymbolic Reinforcement Learning Via Editable Specifications, Vedant Khandelwal, Hong Yung Yip, Amit Sheth

Publications

Reinforcement learning systems are commonly adapted to new settings by retraining or fine-tuning policies. This default is costly, difficult to audit, and poorly aligned with structured requirement changes such as revised safety rules, new operational constraints, or updated user preferences. We argue for an alternative abstraction: adaptation via edits to an external, human-readable specification that the agent consults at execution time. We propose conditioning decision-making on an editable knowledge graph encoding (i) rules capturing action applicability and high-level effects, (ii) hard constraints defining feasibility, and (iii) soft preferences shaping tradeoffs among feasible behaviors. Requirement changes become graph edits, not policy …


Implications Of Quantum Computing For Enterprise Cybersecurity And Data Integrity, Manikantha Varaprasad Inakollu Jan 2026

Implications Of Quantum Computing For Enterprise Cybersecurity And Data Integrity, Manikantha Varaprasad Inakollu

Computer Science and Engineering Faculty Publications

Quantum computing represents a paradigm shift in computational capabilities that poses both unprecedented threats and opportunities for enterprise cybersecurity. This research examines the implications of quantum computing advancement on current cryptographic systems, data protection mechanisms, and organizational security frameworks. Through analysis of quantum computing developments from 2019-2024 and surveys of 280 cybersecurity professionals across various industries, this study identifies critical vulnerabilities in existing encryption standards and explores emerging quantum-resistant solutions. The findings reveal that approximately 78% of enterprises remain unprepared for quantum threats, with current RSA and ECC encryption systems facing potential compromise within the next 10-15 years. The research …


Structural Batteries For Aerospace Applications, Tariqullah Wardak Jan 2026

Structural Batteries For Aerospace Applications, Tariqullah Wardak

Honors Undergraduate Theses

There is increasing pressure on the aviation sector to lower carbon emissions and switch to entirely electric and hybrid propulsion systems. However, the feasibility of standard lithium-ion batteries for long-range aircraft is limited, as they add substantial weight and occupy significant volume. Structural batteries, which combine load-bearing capability with energy storage, offer a potential pathway to lighter and more efficient aerospace systems.

This work investigates a carbon-fiber-based structural battery that utilizes carbon fiber as both a current-collecting, load-bearing electrode and a component of the composite structure. In contrast to lithium-ion chemistries, a zinc-based aqueous electrolyte is chosen for better environmental …


Age-Related Hearing Loss Involves Mitochondrial Dna Instability And Copy Number Depletion In The Cochlea: Insights From In Vivo And In Vitro Models, Akil Turner, Bo Ding, Xiaoxia Zhu, Tam Nguyen, Parveen Bazard, Robert D. Frisina Jan 2026

Age-Related Hearing Loss Involves Mitochondrial Dna Instability And Copy Number Depletion In The Cochlea: Insights From In Vivo And In Vitro Models, Akil Turner, Bo Ding, Xiaoxia Zhu, Tam Nguyen, Parveen Bazard, Robert D. Frisina

Chemical and Biochemical Engineering Faculty Research & Creative Works

Age-related hearing loss (ARHL) is a highly prevalent sensory neurodegenerative disorder that involves various molecular mechanisms. The present study investigated if age-related oxidative stress (OS) induces alterations in mitochondrial DNA (mtDNA) copy number and heteroplasmy, using complementary in vivo and in vitro models. Aged (30-month) CBA/CaJ mice have elevated auditory brainstem response (ABR) thresholds amplitudes vs. young (3-month) CBA/CaJ mice, a key physiological characteristic of ARHL The in vitro experiments employed the strial SV-K1 cochlear cell line treated with hydrogen peroxide (H2O2). Both the aged cochleae and H2O2-treated cells exhibited a significant …


Orchestrating Bone Healing: Biomaterial-Driven Immunoengineering Of The Bone Microenvironment For Advanced Regenerative Therapies, Ah Joung Rachel Yu, Mohammad Reza Zare, Edikan Ogunnaike, Mostafa Yazdi Jan 2026

Orchestrating Bone Healing: Biomaterial-Driven Immunoengineering Of The Bone Microenvironment For Advanced Regenerative Therapies, Ah Joung Rachel Yu, Mohammad Reza Zare, Edikan Ogunnaike, Mostafa Yazdi

Chemical and Biochemical Engineering Faculty Research & Creative Works

Bone regeneration is a multistage and tightly regulated process driven by coordinated interactions between the immune and skeletal systems. While inflammation is essential for initiating repair, its dysregulation contributes to delayed union, nonunion, and impaired healing commonly seen in trauma, chronic disease, and aging. Traditional interventions, including autografts and inert biomaterials, provide structural support but fail to engage or modulate the immune microenvironment that governs successful regeneration. Emerging research in osteoimmunology has revealed the centrality of immune cell populations such as macrophages, T regulatory cells, dendritic cells, and myeloid-derived suppressor cells in directing osteogenesis, angiogenesis, and the resolution of inflammation. …


The Role Of User Experience In Virtual Reality Flight Training: A Comparison With Pc-Based Simulation, Tianxin Zhang, Christina M. Frederick, Barbara Chaparro Jan 2026

The Role Of User Experience In Virtual Reality Flight Training: A Comparison With Pc-Based Simulation, Tianxin Zhang, Christina M. Frederick, Barbara Chaparro

Journal of Aviation/Aerospace Education & Research

The current project explores how user experience (UX) in virtual reality (VR) flight simulation influences both cognitive learning outcomes and procedural skill acquisition when compared to traditional desktop-based simulation.. Using a quasi-transfer of training design, 48 student pilots were randomly assigned to VR, Desktop, or Control groups and trained on the Chandelle maneuver. UX was measured with the User Experience Questionnaire (UEQ), while training effectiveness was evaluated through a post-training knowledge test and recorded maneuver performance on a high-fidelity flight training device. Results indicated that the VR group reported significantly higher UX scores in Attractiveness, Stimulation, and Novelty, and showed …


Navigating The Challenges: Preflight Planning With Notam In Australia’S General Aviation Sector, Joshua Chiang, Guido Carim Junior Jan 2026

Navigating The Challenges: Preflight Planning With Notam In Australia’S General Aviation Sector, Joshua Chiang, Guido Carim Junior

Journal of Aviation/Aerospace Education & Research

Notices to Airmen (NOTAMs) are an integral part of a pilot’s preflight navigational briefing, providing pertinent information in textual format. However, significant shortcomings have been found in the NOTAM system and in its use, with many of the shortcomings revolving around the interface. This study aimed to identify and evaluate the challenges general aviation pilots face when interacting with NOTAMs during preflight navigational planning. A thematic analysis study was conducted and included episodic semi-structured interviews with 15 pilots and document analysis. The interview transcription and excerpts of NOTAMs were analyzed following a thematic analysis technique. The findings of this preliminary …


Integrating Stakeholder Priorities Into Resilience Planning And Investment Decision-Making, Victoria Jeaneen Kraemer Jan 2026

Integrating Stakeholder Priorities Into Resilience Planning And Investment Decision-Making, Victoria Jeaneen Kraemer

Doctoral Dissertations

"Resilience is a system’s ability to bounce back from a disruption. However, resilience needs may vary across different stakeholders. To better integrate stakeholder input into resilience planning and investment decision-making, existing frameworks were combined to develop the Integrated Stakeholder-Centered Resilience Framework. This broad framework is tailorable across contexts and stakeholder types. Research results demonstrate the use of this framework to evaluate the effects of disruptions and represent stakeholder preferences for investments. In the first study, participants were randomly assigned to power outage scenarios, which did not affect their criteria priorities. An exploratory factor analysis revealed two main priorities, (1) Absorption …


Enhanced Hydrophilicity And Self-Cleaning Properties Of Tio₂ Thin Films On Glass For Photovoltaic Applications: Influence Of Precursor Concentration And Light Irradiation, Fatma Refaat, Hany Hashem, Mohamed Mahmoud Gouda, Ibrahim Ahmed, Khaled Abdelwahed, Ahmed Bakr El Basaty Jan 2026

Enhanced Hydrophilicity And Self-Cleaning Properties Of Tio₂ Thin Films On Glass For Photovoltaic Applications: Influence Of Precursor Concentration And Light Irradiation, Fatma Refaat, Hany Hashem, Mohamed Mahmoud Gouda, Ibrahim Ahmed, Khaled Abdelwahed, Ahmed Bakr El Basaty

Trends in advanced sciences and technology

This study investigates the modification of glass substrates with TiO₂ thin films to enhance surface hydrophilicity and self-cleaning behavior. The films were deposited on glass by spin coating using different precursor concentrations, followed by thermal treatment. Structural and optical properties were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and UV–Vis spectroscopy, while surface wettability was evaluated through water contact angle measurements. XRD confirmed the formation of pure anatase TiO₂, while FTIR spectra verified the presence of Ti–O and Ti–O–Ti bonds. Wettability analysis showed that films prepared with the lowest precursor concentration exhibited the …


Hybrid Learning And Optimization Methods For Solving Capacitated Vehicle Routing Problem, Monit Sharma, Hoong Chuin Lau Jan 2026

Hybrid Learning And Optimization Methods For Solving Capacitated Vehicle Routing Problem, Monit Sharma, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

We propose a hybrid quantum–classical framework for the Capacitated Vehicle Routing Problem (CVRP) that integrates the Augmented Lagrangian Method (ALM) with deep reinforcement learning (RL). Directly solving CVRP via Variational Quantum Eigensolver (VQE) requires a slack-based QUBO formulation, where converting inequalities to equalities greatly increases the qubit count. To circumvent this, we employ an ALM-based reformulation that enforces constraints through Lagrange terms instead of slack variables, drastically reducing quantum resource demands. An RL agent, trained with Soft Actor–Critic, adaptively tunes the Lagrange penalties to improve convergence and feasibility. Experiments show that RL-Q-ALM outperforms static-penalty and plain VQE baselines in both …


N-Radii Approach For Multi-Scale Characterization Of Graphite Shape In Cast Iron, Simon N. Lekakh, Laura Bartlett Jan 2026

N-Radii Approach For Multi-Scale Characterization Of Graphite Shape In Cast Iron, Simon N. Lekakh, Laura Bartlett

Materials Science and Engineering Faculty Research & Creative Works

Knowledge of multi-scale particle macro-shape and micro-surface topology is critical in many technical disciplines. Specifically, quality assessment of the shape of the graphite phase in cast irons is essential for day-to-day metal casting operations. Common methods for evaluating particle macro-shape have several drawbacks, often resulting in underestimation of sharp corners and surface texture. In this article, a method based on plotting n-radii from the center of mass to the perimeter and computing multi-scale topological characteristics is described and tested. Parametric tests, involving variations in the number of n-radii and image resolution, were performed to optimize the test parameters. The method …


Modeling Of Transformation Temperatures In Cast Martensitic Stainless Steels-Ca6nm: Effects Of Composition, Heating Rate, And Grain Size, Ugochukwu Agbedo, Mario Buchely, Laura Bartlett, Caelan Kennedy Jan 2026

Modeling Of Transformation Temperatures In Cast Martensitic Stainless Steels-Ca6nm: Effects Of Composition, Heating Rate, And Grain Size, Ugochukwu Agbedo, Mario Buchely, Laura Bartlett, Caelan Kennedy

Materials Science and Engineering Faculty Research & Creative Works

Accurate prediction of the critical transformation temperatures Ac1 and Ac3 is one of the essential factors in the heat treatment of CA6NM cast martensitic stainless steel. In this study, the influence of alloy composition, heating rate, and prior austenite grain size on the critical temperatures was quantified using dilatometric measurements and statistical modeling. Six heat treatment conditions produced prior austenite grain sizes ranging from ~75 to 247 µm. Experimental results showed that grain size variations produced only minor changes in Ac1 and Ac3, indicating a weak dependence of transformation temperatures on prior austenite grain size within the investigated range. In …


Multiphysics Simulation And Experimental Validation Of Phase Transformation And Hardness In Jominy End-Quenched Low-Alloy Steels, J. S. Alabi, E. Heidari, M. F. Buchely, K. Chandrashekhara, S. N. Lekakh, R. J. O'Malley, V. A. Athavale, A. Kumar Jan 2026

Multiphysics Simulation And Experimental Validation Of Phase Transformation And Hardness In Jominy End-Quenched Low-Alloy Steels, J. S. Alabi, E. Heidari, M. F. Buchely, K. Chandrashekhara, S. N. Lekakh, R. J. O'Malley, V. A. Athavale, A. Kumar

Materials Science and Engineering Faculty Research & Creative Works

High-volume industrial continuous hot-rolled steel heat treatment processes involve sophisticated multi-phase modeling. The performance of a given process can be optimized by coupling phase transformation kinetics with the cooling conditions of the process. This study develops a multiphysics model to simulate an intensive quenching process for steel, which is inherently transient and highly dependent on numerous parameters. The simulated object was a Jominy end-quenched specimen geometry using two commercial steels, AISI 4130 and AISI 4140, with the goal of transferring a verified methodology to the heat treatment process for industrial heavy-section products (bars, slabs). The simulation employs thermal, mechanical, and …


The Effects Of Membrane Structure And Filtration Conditions On Virus Filtration, Wenbo Xu, Xianghong Qian, Hironobu Shirataki, Daniel Strauss, Sumith R. Wickramasinghe Jan 2026

The Effects Of Membrane Structure And Filtration Conditions On Virus Filtration, Wenbo Xu, Xianghong Qian, Hironobu Shirataki, Daniel Strauss, Sumith R. Wickramasinghe

Biomedical Engineering Faculty Publications and Presentations

Virus filtration is used for validation of virus clearance in the manufacture of monoclonal antibodies. Requirements for this size exclusion process include 10,000-fold reduction of virus particles and at least 95 % recovery of the monoclonal antibody in the permeate. The size difference between the rejected parvovirus particles, 25 nm, and monoclonal antibody, 10-12 nm, is about two. Membranes are designed with pore sizes around the average size of the parvovirus. Given the polydispersity in membrane pore size and virus particles, filter performance is dependent on membrane properties, feed and operating conditions. Compromised performance usually occurs due to product related …


Adaptive Machine Learning Framework For Microstructural Optimization And Mechanical Performance Prediction In Steels, Henry Adekola Haffner Jan 2026

Adaptive Machine Learning Framework For Microstructural Optimization And Mechanical Performance Prediction In Steels, Henry Adekola Haffner

Doctoral Dissertations

Evolution of microstructures, such as polygonal ferrite, acicular ferrite, bainite, and martensite, plays a pivotal role in determining the final microstructural and mechanical properties of steel products. Given the established inter-relationship between processing parameters, microstructure, properties, and performance, precise control of phase transformation is essential to achieve pre-determined properties. To understand transformation routes in different steel grades, time-temperature-transformation (TTT) and continuous-cooling-transformation (CCT) diagrams are necessary and can be described using the Johnson-Mehl-Avrami-Kolmogorov equation and Scheil’s additivity rule. This study presents a comprehensive computational framework for predicting and optimizing microstructure and mechanical properties in advanced high-strength steels (AHSS) using adaptive machine …


Investigations In Hydrogen Ironmaking, Joseph William Govro Jan 2026

Investigations In Hydrogen Ironmaking, Joseph William Govro

Doctoral Dissertations

The purpose of this research is to contribute to the Grid Interactive Steelmaking with Hydrogen (GISH) project. This research investigates the viability of both producing and melting Direct-Reduced Iron (DRI) utilizing hydrogen. Conventional CO reduced DRI will be referred to as “C-DRI” and DRI produced using hydrogen gas will be referred to as “H-DRI”.

An H-DRI pilot plant was constructed in Golden Colorado. The pilot plant was commissioned and successfully operated four campaigns. Process improvements were made throughout the campaigns and the process was optimized. In addition to running the pilot plant in a pure hydrogen condition, the pilot plant …


Zirconium Carbide Based Materials For Extreme Aerospace Environments, Nathaniel Hyman Blatt Jan 2026

Zirconium Carbide Based Materials For Extreme Aerospace Environments, Nathaniel Hyman Blatt

Doctoral Dissertations

This research focuses on the processing and properties of zirconium carbide-based materials to promote their use in extreme environment aerospace applications, including nuclear thermal propulsion and hyper sonics. Several carbide systems including ZrC, ZrC-Mo cermets, (Zr, Nb)C, and a high entropy carbide were developed. The ZrC-Mo cermet was studied extensively to understand the effect of starting carbide grain size on the final microstructure, composition, elastic moduli, hardness, fracture toughness, room and elevated temperature flexural strength, thermal diffusivity, electrical resistivity, thermal expansion coefficient, and thermal conductivity. It was shown that heat transport in the cermets was dominated by the ZrC phase …