Digital Commons Network^™

Interpretable Battery Soh Prediction: A Comparative Interpretability Framework For Multi-Architecture Ml Models, Shafiyee Islam, Gon Namkoong

Electrical & Computer Engineering Faculty Publications

This work introduces a unified interpretability-efficiency framework for lithium-ion battery state of health (SOH) prediction using hybrid deep learning architectures. We comparatively analyze four hybrid models: CNN LSTM MultiHead, CNN Feature Extractor LSTM, DNN LSTM, and DNN BiLSTM to disentangle how network topology, feature composition, and computational design influence both predictive fidelity and physical interpretability. By integrating Monte Carlo Shapley (MC Shapley), background occlusion SHAP (BoSHAP), and ablation analysis, we quantify the contribution and robustness of five electrochemical feature groups: time, capacity, voltage, dQ/dV and peaks of dQ/dV from NASA battery dataset. The results reveal a consistent dominance of differential …

An Explainable Cs-Mitigation Triangular (Ecsmt) Framework To Secure Graph Neural Networks, Sabah Ettahri, Sergio Pallas Enguita, Chung-Hao Chen, Wen-Chao Yang

Electrical & Computer Engineering Faculty Publications

This research addresses cyber risk by defending against backdoor attacks on Graph Neural Networks (GNNs). We propose the Explainable Complex System-Mitigation Triangular (ECSMT) Framework, which integrates Robust Training, Graph Regularization, and Data Sanitization into a lightweight, hardware-efficient defense layer. To evaluate structural generalizability, we conducted empirical evaluations across three distinct benchmark domains (AIDS, MUTAG, and PROTEINS) using a Graph Isomorphism Network (GIN) backbone. Under a baseline 5% backdoor subgraph trigger injection ratio, ECSMT achieves excellent utility retention, securing a Clean Accuracy (CA) of 97.33% (±0.62%) while reducing the Attack Success Rate (ASR) from 97.00% down to 69.45% on the primary …

Dynamic Direct Voltage Control Under Maximum Torque Per Ampere For Interior Pmsms, Mohamad Alzayed, Hicham Chaoui, Alaref Elhaj

Electrical & Computer Engineering Faculty Publications

A novel method for controlling the speed of interior permanent magnet synchronous motors (IPMSMs), known as the current-sensing-based dynamic direct voltage control method under the maximum torque per ampere (MTPA) concept, is introduced. This technique achieves precise tracking of machine velocity by determining the optimal combination of voltage amplitude and angle for each specific motor velocity and current/load condition. Unlike previous studies, this approach takes into account the transient model of the machine, resulting in improved accuracy during dynamic operating conditions compared with existing methods in the literature. Moreover, a comparative analysis is conducted involving different direct voltage MTPA speed …

Generative Ai-Driven Optimization In Flexible And Reconfigurable Manufacturing Systems, Salah Hammedi, Hicham Chaoui, Lotfi Nabli

Electrical & Computer Engineering Faculty Publications

Flexible and Reconfigurable Manufacturing Systems (FRMSs) are essential for coping with variability in modern production environments; however, efficient scheduling and rapid reconfiguration remain challenging. This paper presents a hybrid optimization framework that integrates Colored Petri Net (CPN) modeling with Generative Artificial Intelligence (GenAI) to enhance scheduling performance and system adaptability. The CPN formalism ensures verifiable modeling of system dynamics, while a transformer-based generative model produces candidate scheduling and reconfiguration strategies. Simulation experiments were conducted under static, dynamic, and adaptive scenarios, including machine breakdowns and dynamic job arrivals. Performance was evaluated using makespan, mean flow time, machine utilization, and reconfiguration latency. …

Generalized Inverter Fault Detection Using Normalized Current Features And A Lightweight Bilstm Network, Mohammad Zamani Khaneghah, Mohamad Alzayed, Hicham Chaoui

Electrical & Computer Engineering Faculty Publications

Fault detection and diagnosis of three-phase inverter-fed motor drives is essential for ensuring system reliability, safety, and continuous operation in applications such as electric vehicles and industrial automation. This paper proposes a data-driven fault detection framework based on normalized current features and a lightweight bidirectional long short-term memory (BiLSTM) network which can be generalized to different motor power rating in the same controller system. A compact set of six time-domain features, consisting of the mean and root-mean-square (RMS) values of the phase currents, is extracted and normalized with respect to the average RMS value. This normalization effectively removes dependency on …

Fault Tolerance Of Accelerated Asynchronous Fixed-Point Iterations On Flexible Computing Infrastructure, Evan Coleman, Masha Sosonkina

Electrical & Computer Engineering Faculty Publications

Asynchronous iterative methods tolerate straggling processors by allowing workers to proceed with stale data, but at a cost: the iterates become inconsistent, potentially degrading convergence. We investigate whether convergence accelerators such as Anderson acceleration compensate for this degradation. We experimentally study three fixed-point iterations: the Jacobi method for sparse linear systems, value iteration for the Bellman equation, and the Hartree–Fock self-consistent field (SCF) iteration. The experiments are conducted using a high-performance execution framework, Ray, which abstracts the complexity of distributed systems and enables code parallelization and fault injection with minimal changes.

We establish two main results. First, straggler tolerance is …

Affordable Course Content And Open Education Resources For Undergraduate Courses Teaching Fundamentals Of Wireless Communications And Networking, Dimitrie C. Popescu, Otilia Popescu

Electrical & Computer Engineering Faculty Publications

Wireless communication systems and networks along with the services they provide have become an essential component of the modern 21st century society, fueling job growth in the wireless industry and increasing the need for engineers specialized in wireless communication systems. As a consequence, over the past two decades, undergraduate courses teaching fundamentals of wireless communication systems and networks have become common in electrical and computer engineering and technology programs. At the same time, the number of textbooks dedicated to wireless systems and networks published by mainstream publishers has also grown, with availability in various formats and offerings and a significant …

On Distribution Matching For Probabilistic Constellation Shaping, Dimitrie C. Popescu, Cameron Kowski

Electrical & Computer Engineering Faculty Publications

Distribution matching (DM) transforms a stream of equally likely bits into digital symbols that correspond to a specific digital modulation scheme with probabilities of occurrence following a specified statistical distribution. This technique is referred to as probabilistic constellation shaping (PCS), and using the Maxwell–Boltzmann (MB) distribution improves spectral and energy efficiency of digital modulation schemes by enabling more frequent transmissions of lower energy digital symbols. The background behind PCS is presented in the paper and the two main DM methods widely used in practice are discussed, outlining scenarios in which one DM method may be preferable over the other. For …

A Low-Cost Fourier-Based Dual-Pump Mock Circulatory Loop For Arterial Pressure Waveform Reproduction, Victor K. Tsui, Kouhyar Tavakolian, Daniel Ewert

Electrical & Computer Engineering Faculty Publications

Cardiovascular diseases are among the leading causes of death worldwide, creating a need for reliable hemodynamic testing platforms for cardiovascular device evaluation and therapeutic development. Mock circulatory loops (MCLs) provide effective in vitro platforms for reproducing physiological and pathological pressure conditions; however, many existing systems remain limited in programmability, waveform fidelity, standardization, and affordability. This study presents a cost-effective dual-pump hybrid MCL (hMCL) that independently regulates baseline and pulsatile pressure components using Fourier-based harmonic synthesis. Reference arterial pressure waveforms were decomposed into harmonic components, and their amplitudes, frequencies, and phase shifts were converted into pulse-width-modulation signals for dual-pump actuation. Validation …

Just Okay Is Not Okay, Cam Torrens

Mighty Pen Project Anthology & Archive

A career Air Force commander who's spent thirty years teaching decisive leadership avoids the one confrontation that would complicate his retirement.

Articles, stories, and other compositions in this archive were written by participants in the Mighty Pen Project. The program, developed by author David L. Robbins, and in partnership with Virginia Commonwealth University and the Virginia War Memorial in Richmond, Virginia, offers veterans and their family members a customized twelve-week writing class, free of charge. The program encourages, supports, and assists participants in sharing their stories and experiences of military experience so both writer and audience may benefit.

Letter To The Board, Anonymous Author

Mighty Pen Project Anthology & Archive

A Marine lieutenant colonel challenges the military’s definition of the “ideal” commander, defending a career shaped by family, service, and leadership over tradition.

Articles, stories, and other compositions in this archive were written by participants in the Mighty Pen Project. The program, developed by author David L. Robbins, and in partnership with Virginia Commonwealth University and the Virginia War Memorial in Richmond, Virginia, offers veterans and their family members a customized twelve-week writing class, free of charge. The program encourages, supports, and assists participants in sharing their stories and experiences of military experience so both writer and audience may benefit.

Senescent Fibroblasts In Aging And Pulmonary Fibrosis, Sara B. Palega, Aiwei Y. Borengasser, Yan Y. Sanders

Department of Biomedical and Translational Sciences Faculty Publications

Aging is a major risk factor for many chronic lung diseases, including Idiopathic Pulmonary Fibrosis (IPF), a fatal and incurable disease characterized by progressive fibrotic remodeling. Age-associated structural alterations, impaired regenerative capacity, and dysregulated cellular signaling collectively create a pro-fibrotic microenvironment. A central driver of this pathological shift is the accumulation of senescent cells, which undergo irreversible growth arrest and develop a robust pro-inflammatory senescence-associated secretory phenotype (SASP). Emerging evidence identifies senescent lung fibroblasts as critical mediators of IPF pathogenesis. These cells promote excessive extracellular matrix deposition, myofibroblast differentiation, and tissue stiffening, while simultaneously impairing epithelial regeneration. Together, these effects …

Neighborhood Socioeconomic Deprivation And Physical Activity Associate With Extracellular Vesicle Size And Cargo In A Community-Based Cohort Of Women, Yvonne Baumer, Elizabeth M. Aquino Peterson, Matthew R. Bavuso, Noel Miller, Cristhian A. Gutierrez-Huerta, Nithya P. Vijayakumar, Sam J. Neally, Kaveri Curlin, Valerie M. Mitchell, Billy S. Collins, Neelam R. Redekar, Subrata Paul, Anca D. Dobrian, Tiffany M. Powell-Wiley

Department of Biomedical and Translational Sciences Faculty Publications

African American (AA) women face disproportionate cardiovascular disease (CVD) risk due to adverse social determinants of health (SDoH), including lower socioeconomic status (SES). Physical activity (PA) and plasma extracellular vesicles (EVs) modulate CVD risk, but their relationships with SDoH remain unclear. This study examines associations between SDoH, PA, and plasma EVs in a Washington, DC-based cohort of at-risk AA women. Participants (N = 24, Age: 57 ± 12, BMI: 35 ± 6, ASCVD: 9 ± 5) joined the Step It Up Community-Engaged, Digital Health Physical Activity Intervention pilot study. EVs were isolated from fasting plasma samples. Multivariable regression, adjusted for …

Inhibition Of Histone Demethylase Lsd1 Suppresses Cd47 Expression And Enhances Efficacy Of Cd47 Blockade In Breast Cancer, Fengjie Jiang, Yu Shen, Bing Li, Michael Henry, Nancy Davidson, Yi Huang

Department of Biomedical and Translational Sciences Faculty Publications

Background CD47 functions as a “don’t eat me” checkpoint, inhibiting macrophage-mediated phagocytosis in triple-negative breast cancer (TNBC). While anti-CD47 therapies can restore immune surveillance, their efficacy in TNBC is often limited by immune evasion and drug development challenges.

Methods We investigated the crosstalk between the histone demethylase lysine-specific demethylase 1 (LSD1) and CD47 signaling in TNBC using in silico datasets, isogenic cell lines, conditional BRCA1 knockout models, and syngeneic mouse models. Techniques such as immunohistochemistry, multiplex immunofluorescence, immunoprecipitation, protein ubiquitination, chromatin immunoprecipitation, chemotaxis, flow cytometry, and phagocytosis assays were employed to examine the epigenetic regulation of CD47 by LSD1 and …

The Interplay Between Loneliness, Cortisol, And Nk Cell Function: The Role Of Cortisol In Nk Cell Dysfunction, Abhinav Saurabh, Yvonne Baumer, Laurel G. Mendelsohn, Elizabeth M. Aquino Peterson, Dana Sadler, Shirley J. Lopez De Leon, Ayushi Dave, Andrew S. Baez, Lola R. Ortiz-Whittingham, Mario A. Pita, Manuel A. Cintron, Hannatu A. Tarfa, Sandy T. Reynolds, Shelby R. Hicks, Sonal Sharda, J. Eleanor Seo, Maria Lopez-Ocasio, Pradeep K. Dagur, Skyler A. Kuhn, Neelam R. Redekar, James F. Troendle, Ayanna L. Wells, Marie Marah, Katherine J. Tolentino, Michael J. Corley, Alika K. Maunakea, Lynnette K. Nieman, Marcus R. Andrews, Tiffany M. Powell-Wiley

Department of Biomedical and Translational Sciences Faculty Publications

Chronic psychosocial stressors contribute to cardiovascular disease (CVD) and related risk factors, particularly in under-resourced communities. Psychosocial stressors activate the hypothalamic-pituitary-adrenal (HPA) axis, leading to sustained cortisol action on immune cells. Natural killer (NK) cells are altered in distribution and function in cardio-metabolic diseases; however, pathways linking cortisol as a marker of chronic stress to NK cell dysfunction remain understudied. We recruited 186 African American women from the Step It Up Community-Engaged, Digital Health Physical Activity Intervention study and collected cortisol, NK cell measures, and psychosocial stress measures using validated questionnaires, including chronic stress and loneliness. Plasma cortisol levels were …

Stim1-Dependent Treg Dysfunction Promotes Cardiometabolic Hfpef: Insights From Patients And Animal Studies, Balaji Srinivas, Alluri Kiran, Hongmei Peng, Jiang Xu, Paula Fortuno, Jennifer May, Ismail El Moudden, Nour-Eddine Rhaleb, John M. Herre, Raymond L. Benza, Khalid Matrougui

Department of Biomedical and Translational Sciences Faculty Publications

Background

Heart failure with preserved ejection fraction (HFpEF) arises from chronic cardiometabolic and vascular stress and is increasingly recognized as an inflammatory syndrome with immune dysregulation. Regulatory T cells (Tregs) are critical modulators of cardiovascular inflammation, yet the mechanisms driving Treg dysfunction in HFpEF remain poorly defined. stromal interaction molecule 1 (STIM1)-dependent calcium signaling is a key stress-responsive pathway in immune cells; however, its role in Treg maladaptation during HFpEF remains unknown.

Methods

Circulating Tregs from patients with and without HFpEF were analyzed for abundance, STIM1 expression, and stress-associated signaling pathways. To establish causality, mice with Treg-specific deletion of STIM1 …

When Slides Replace Thinking: How Powerpoint Culture Undermines Conceptual Learning In Engineering Education, Shahin Nayyeri Amiri, Hamid Eisazadeh

Civil & Environmental Engineering Faculty Publications

Engineering education has gradually shifted from deep conceptual teaching to a culture dominated by presentation slides. In many universities today, core courses such as Statics, Dynamics, and Mechanics of Materials are taught through PowerPoint files rather than through reasoning, derivation, and problem solving. While slide-based instruction may appear efficient, it encourages passive learning and has severely weakened students’ ability to think independently and make sound engineering judgments. Traditionally, these fundamental courses were taught by seasoned instructors who had mastered the subjects and took genuine pride in explaining complex ideas with clarity and passion. They guided students through the logic behind …

Flood-Season Surface Water-Groundwater Interactions Across Distinct Geomorphic Units In A Yellow River Great Bend Tributary Basin, Yinlong Wang, Ruizhong Gao, Debin Jia, Xixi Wang, Tingxi Liu, Xiaomin Liu, Shiming Bai

Civil & Environmental Engineering Faculty Publications

Surface water-groundwater interactions are complex in the Great Bend region of the Yellow River. Clarifying water exchange and source differences among geomorphic units is important for understanding regional hydrological processes and improving water resources management. In this study, the Wulanmulun River Basin, a typical tributary of the Yellow River, was selected as the study area. A total of 90 water samples were collected, including 25 river water samples, 43 groundwater samples, and 22 precipitation samples. Gibbs diagrams, multivariate statistical analysis, PMF, and MixSIAR models were used to investigate the hydrochemical and isotopic characteristics, source contributions, and transformation relationships of surface …

Modeling Hepa Filter Media Performance And Evaluation Of Filtration Leak Test Success, Daniel M. Abraham, Steven J. Eckels, Shahin N. Amiri

Civil & Environmental Engineering Faculty Publications

This research presents a cost-effective microscale modeling analysis of high-efficiency particulate air (HEPA) filter media. We analyzed leak-free and leaking media with known leak sizes. A three-dimensional fibrous model with non-homogeneous fiber diameters (0.2–2 µm) and a packing density of 7.5% was developed to replicate a HEPA filter sheet (H14) microstructure. The objective was to simulate and analyze the pressure drop and collection efficiency of nanofibrous media for aerosol particles with a diameter of d_p ≤ 0.5 µm. The results were compared to prior experimental and theoretical models, exhibiting a high level of agreement with pressure drop and efficiency …

Medical Students Report Coherent Ethical Orientations Towards Ai Across Academic And Clinical Domains, With No Clear Association With Perceived Technical Readiness: A Cross-Sectional Pilot Study, Ismail El Moudden, Madison Baldauf, John Millerhagen, Anca Dana Dobrian

Department of Obstetrics & Gynecology Faculty Publications

Background

Whether perceived technical AI competency is associated with greater ethical openness to AI integration, a relationship often assumed in curricular design, remains empirically untested. This pilot study examined relationships between perceived AI readiness, ethical perspectives toward AI integration, and curricular needs among medical students.

Methods

A cross-sectional survey was administered to medical students at a single U.S. institution from September through November 2025. The survey assessed self-reported AI readiness, ethical perspectives across academic and clinical domains, and responses to 22 scenario-based ethical items; all measures were student self-reports, and findings reflect student perceptions. Composite indices were created for Perceived …

Parametric Study Of Yields And Properties Of Corn Stover-Derived Hydrothermal Liquefaction Products By Using Statistical Approaches, Isamu Umeda, Meicen Liu, Jiefu Wang, Yi Zheng, Zhiwu Wang, Jaya Shankar Tumuluru, Sandeep Kumar

Civil & Environmental Engineering Faculty Publications

Hydrothermal liquefaction (HTL) of lignocellulosic biomass produces multiple product fractions, including solid residue (SR), heavy bio-oil (HBO), aqueous phase (AP), and light bio-oil (LBO). This study mainly applied principal component analysis (PCA) and regression modeling to predict AP solution weight, LBO weight and fuel characteristics, and HTL wastewater biodegradability, as well as to improve prediction accuracy for SR and HBO under various operating conditions (temperature: 250–350 °C, residence time: 5–60 min, and the combined solid loading of three batches: 15–45 g). A complementary relationship between SR and AP weights found in PCA enabled the estimation of AP weight based on …

Multi-Isotope Tracing Reveals Nitrate And Sulfate Sources And Fate Across Contrasting Activity Zones In A Semi-Arid Basin Of Northern China, Chang Yue, Ruizhong Gao, Limin Duan, Tianke Su, Xixi Wang, Tingxi Liu, Guoqiang Wang

Civil & Environmental Engineering Faculty Publications

In semi-arid surface water-groundwater systems, nitrate (NO₃^–) and sulfate (SO₄²^–) are jointly influenced by natural processes and anthropogenic activities, yet how their sources, transformations, and export vary across contrasting activity zones remains insufficiently understood. Integrating hydrochemistry, multiple stable isotopes, a Bayesian isotope mixing model, and representative-section flux analysis, this study investigated the source compositions, transformation processes, and export differences of NO₃^– and SO₄²^– in the Dahei River Basin.   New hydrological insights for the region: Results showed greater SO₄²^– enrichment in high-activity zones, whereas NO₃^– exceedance was more prominent in low-activity zones. In …

Resilient Built Environment: An Overview On Design Strategies For Coastal Adaptation To Sea Level Rise, Farzaneh Soflaei, Gelareh Abdolzadeh, Navid Ziaee, Mohammad Amin Jafari, Faeghe Borhani

Civil & Environmental Engineering Faculty Publications

This paper delves into the escalating risks faced by urban coastal communities due to tidal and storm flooding, exacerbated by climate change-induced Sea Level Rise (SLR). Projections indicate a potential increase in sea levels by at least 3 feet by 2100, with historical data revealing an average annual rise of 1.2-1.7 mm since the 1900s. With over 300 million individuals inhabiting coastal areas, low-lying regions emerge as particularly vulnerable to the impacts of SLR. This accelerated rise amplifies the significant challenge of nuisance flooding, a local-scale issue aggravated by high tide and winds, leading to inundation, road closures, infrastructure deterioration, …

Physics-Based Multi-Hazard Fragility Modeling Of Low-Rise Wood-Frame Buildings Under Hurricane-Induced Wind And Surge, Mumtasirun Nahar, Abdullah M. Braik, Mohammad Syed, Maria Koliou, Petros Sideris

Civil & Environmental Engineering Faculty Publications

Coastal buildings are exposed to concurrent hurricane-induced wind and storm surge, yet their vulnerability is commonly assessed using separate single-hazard models that neglect hazard interaction. This study developed a physics-based finite element framework to evaluate the performance of a low-rise light wood-frame building under simultaneous wind and surge-wave loading. A detailed three-dimensional model was constructed using a sub-assembly strategy that explicitly represented framing members, sheathing systems, and critical connections. Structural response was evaluated across a hazard space defined by wind speed, still-water depth, and flow velocity, and component- and system-level fragility functions were derived using Monte Carlo simulation and generalized …

Gain-Delay Decoupling In Human Stimulus Frequency Otoacoustic Emissions Reveals Constraints On Cochlear Nonlinear Amplification, Yoshita Sharma, Arturo Moleti, Renata Sisto, Teresa Botti, Hansapani Rodrigo, Sri Mishra

School of Mathematical & Statistical Sciences Faculty Publications

Purpose: The nonlinear cochlear amplifier, driven by outer hair cells, underlies the remarkable sensitivity and frequency selectivity of the mammalian auditory system. Stimulus frequency otoacoustic emissions (SFOAEs) provide a noninvasive window into these active cochlear processes, yet the relationship between emission gain and delay across stimulus levels remains incompletely understood. This study examined the level dependence of SFOAEs in normal-hearing human listeners to characterize cochlear nonlinear response properties. We tested how emission gain and delay vary with stimulus level and estimated the frequency of the apical–basal transition associated with the breakdown of the approximate local scaling symmetry.

Methods: SFOAEs were …

Good Girl Bootcamp: Performative Femininity, Purity Culture, And Other Things Girls Are Taught, Kiersten Holland

Masters Theses

Performative femininity is a dangerous and controlling idea that subjugates women and places their inherent worth on how well they can conform to societal standards in male dominated spaces. Consequently, the reactionary messaging that surfaced as a result of these social pressures created a series of stereotypical female characterizations often depicted in the material and visual cultures of each period. By comparing contemporary literature with literature from the Victorian time period, it emphasizes the longstanding and controlling gender stereotypes pervasive throughout the past few centuries. This thesis attempts to understand and analyze the way that literature both critiques and supports …

Investigating The Association Between Polycystic Ovary Syndrome (Pcos) And Idiopathic Intracranial Hypertension (Iih): A Cross-Sectional Analysis, Savannah L. Adams

Graduate Studies Theses and Dissertations 2026

Polycystic ovary syndrome (PCOS) and idiopathic intracranial hypertension (IIH) are chronic conditions that disproportionately affect women of reproductive age and share several metabolic risk factors, including obesity, insulin resistance, and hormonal dysregulation. Despite growing clinical interest in a potential relationship between these conditions, limited research has examined awareness, knowledge, symptom presentation, and barriers to healthcare among young adult populations. The purpose of this study was to investigate awareness, knowledge, perceived healthcare barriers, and potential associations between PCOS and IIH among college-aged individuals. A cross-sectional survey was administered to students aged 18-25 at the University of Central Florida through classroom recruitment …

Benchmarking And Advancing Heterogeneous Data Reasoning With Large Language Models, Yebowen Hu

Graduate Studies Theses and Dissertations 2026

Large language models (LLMs) increasingly face complex real-world tasks requiring complex reasoning over heterogeneous inputs, including text, numbers, and structured data. This dissertation first investigates the capability boundaries of LLMs under such scenarios. Through the MeetingBank and SportsMetrics benchmarks, we show that while LLMs exhibit linguistic fluency, they struggle with factual accuracy, information density, and quantitative cross-referencing in meeting summarization and sports analysis. Using DecipherPref, a pair-wise evaluation framework grounded in the Bradley-Terry-Luce model, we further probe LLMs' inherent preferences for information-rich and lengthy inputs, and we identify critical deficiencies in financial decision-making through DeFine, where models lack precise insight …

Investigation Of Bulk And Periodically Stacked X(2) And X(3) Materials Using Mid-Infrared Femtosecond Pulses, Woraprach Kusolthossakul

Graduate Studies Theses and Dissertations 2026

Mid-infrared (MIR) spectral region represents a vital part of the electromagnetic spectrum, offering applications in spectroscopy, biomedicine, and remote sensing. However, there are no direct broadband MIR laser sources. Nonlinear frequency conversion techniques using second-order nonlinear materials, such as optical parametric oscillator (OPO) and intra-pulse difference frequency generator (IDFG), are promising methods for generating a broadband MIR spectrum. To achieve an efficient conversion, the phase matching condition between the interacting waves of the nonlinear process must be satisfied. Quasi-phase matching (QPM) is a special technique that enables efficient nonlinear processes in materials that cannot be conventionally phase matched using birefringence. …

Odd Colorings Of Graphs With Maximum Degree And Surface Conditions, Matthew Kyle

Graduate Studies Theses and Dissertations 2026

A proper vertex coloring of a graph is said to be odd if, for each vertex, there is a color that is present an odd number of times in its neighborhood. Introduced as a softening of other coloring problems, this problem has recently seen much research interest. It has been conjectured that all planar graphs are odd-5-colorable. Further research has suggested bounds for odd coloring numbers of graphs with different maximum degree conditions, different girths, and on different surfaces; we progress results in all of these areas. We improve an upper bound for odd coloring numbers of graphs of maximum …