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Discriminative And Generative Video Modeling, Anh Pha Nguyen
Discriminative And Generative Video Modeling, Anh Pha Nguyen
Graduate Theses and Dissertations
Video modeling stands at the core of modern computer vision, enabling progress in domains such as surveillance, autonomous driving, and instructional assistance. Yet the complexity of spatiotemporal dynamics, multimodal integration, and the need for scalable and generalizable models present significant challenges. This dissertation addresses these issues from three complementary perspectives: discriminative modeling, multimodal (vision + language) alignment, and generative approaches, contributing new methods, datasets, and paradigms for advancing video understanding. In the discriminative setting, we propose a domain-adaptive framework for crowd counting that employs entropy minimization and adversarial learning to improve cross-domain generalization, and introduce a single-stage global association method …
Optimizing Cobb Mx X 500 Broiler Diets Through The Investigation Of Lysine And Energy Synergies, Soybean Processing “Add-Backs” Ingredients, And Soybean Genotype Amino Acid Selection, Savannah Caroline Wells
Optimizing Cobb Mx X 500 Broiler Diets Through The Investigation Of Lysine And Energy Synergies, Soybean Processing “Add-Backs” Ingredients, And Soybean Genotype Amino Acid Selection, Savannah Caroline Wells
Graduate Theses and Dissertations
This dissertation explored strategies to optimize Cobb MX x 500 broiler chicken nutrition by investigating lysine and energy synergies, the utilization of soybean processing by-products (“add-backs”), and soybean genotype selection for enhanced amino acid composition. Three independent but complementary research objectives were pursued to improve feed efficiency, sustainability, and cost-effectiveness in modern broiler production. The first objective assessed the interactive effects of dietary lysine and metabolizable energy (ME) on the performance and carcass traits of Cobb MX × 500 broilers. Using a central composite design, nine dietary treatments were formulated across multiple feeding phases. Results demonstrated that broiler performance responded …
Implementation Of A Three-Port Solar Converter With A Battery Energy Storage System, Maison Christopher Phipps
Implementation Of A Three-Port Solar Converter With A Battery Energy Storage System, Maison Christopher Phipps
Graduate Theses and Dissertations
The increasing deployment of distributed solar and energy storage systems has created the need for integrated power converters that can efficiently manage photovoltaic (PV) generation, battery energy storage, and grid-tied AC output. This thesis presents the implementation and validation of a 5kW non-isolated Three-Port Converter (TPC) adapted for residential solar applications. The converter consolidates three power stage into a high-frequency, compact architecture: a unidirectional boost converter for PV input, a bidirectional interleaved buck-boost converter for battery energy storage, and a configurable DC/AC inverter for 120Vac single-phase output. The system is controlled using a central controller implemented on a TI C2000™ …
Design And Optimization Of High-Frequency Medium-Voltage Dual Active Bridge Dc/Dc Converter Using Sic Device, Hui Cao
Graduate Theses and Dissertations
High frequency Dual Active Bridge (DAB) converters have become a key enabling technology in medium- and high-power applications such as renewable energy integration, electric vehicle fast charging, and emerging DC power distribution systems. However, when operating at high power and high frequency, DAB converters face critical challenges including limited soft-switching range, uneven semiconductor loss distribution, deadtime-induced resonance, switching-frequency constraints of wide-bandgap (WBG) devices, and transformer DC bias during dynamic transitions. This dissertation addresses these challenges through advancements in modulation strategies and converter architecture. First, an enhanced triple-phase-shift (E-TPS) modulation scheme is proposed to achieve balanced switching and conduction losses across …
Programmable Network Approaches To Resilience And Security In Phasor Measurement Unit Networks, Zhiyao He
Programmable Network Approaches To Resilience And Security In Phasor Measurement Unit Networks, Zhiyao He
Graduate Theses and Dissertations
The security and resilience of smart grids are critical for ensuring reliable and stable power delivery. As modern power systems evolve to incorporate more advanced sensing and control capabilities, Phasor Measurement Units (PMUs) have become an important source of high-frequency, time-synchronized measurements that support wide-area monitoring, control, and protection. However, the growing complexity of smart grids and their reliance on real-time communication expose them to a range of cyber threats, including data loss, tampering, and coordinated attacks. This dissertation explores the use of programmable network technologies, particularly P4-based programmable switches, to provide in-network solutions that enhance the reliability and security …
Optimal Network Maintenance And Restoration: Applications And Algorithms, Nayan Chakrabarty
Optimal Network Maintenance And Restoration: Applications And Algorithms, Nayan Chakrabarty
Graduate Theses and Dissertations
In this dissertation, we consider three types of network optimization problems. In Chapter 1, we consider a network maintenance problem which focuses on time-based redeployment of multi-class nodes for reliable wireless sensor network coverage. Whereas previous research on time-based node redeployment assumes nodes are identical with respect to time to failure, we use multiple classes of sensor nodes to represent a scenario where nodes’ times to failure are dependent on positioning in the network. We propose a partial survival signature (PSS) approach for estimating area coverage reliability under a given time-based redeployment policy, where the PSS is estimated by Monte …
Artificial Intelligence For Reliability: Predictive Health Maintenance And Geolocation In Gps-Denied Environments, Rafael Toche Pizano
Artificial Intelligence For Reliability: Predictive Health Maintenance And Geolocation In Gps-Denied Environments, Rafael Toche Pizano
Graduate Theses and Dissertations
In this dissertation, we explore the potential of machine learning and deep learning techniques to enhance the performance and robustness of applications across two major domains. By addressing the challenges within these fields, we demonstrate that we can leverage learning algorithms to obtain substantial improvements in accuracy and robustness. First, we tackle a problem in the field of predictive health maintenance. We propose a novel auto encoder and neural network based methodology to predict failure times in complex aviation systems to learn to distinguish between normal and abnormal operational behavior, and use this information to inform the neural network to …
Design And Testing Of A Gallium Nitride Power Amplifier For High-Temperature Radar Applications, Walker Landry Harbison
Design And Testing Of A Gallium Nitride Power Amplifier For High-Temperature Radar Applications, Walker Landry Harbison
Graduate Theses and Dissertations
This thesis offers the design, fabrication, and evaluation of a gallium nitride (GaN) power amplifier integrated circuit (IC) intended for high-temperature radar applications. Radar systems are used in many different applications, such as defense, aerospace, and weather. For their function, these systems require high power, efficiency, and reliability under a wide range of operating conditions. Taking advantage of the material properties of GaN, including its high breakdown voltage, wide bandgap, and thermal conductivity bolstered by the use of silicon carbide in the substrate, this work focuses on examining amplifier performance in both ambient and elevated temperature conditions. The PA was …
Emotion Analysis And Neural Language Models For Classification, Andrew Mackey
Emotion Analysis And Neural Language Models For Classification, Andrew Mackey
Graduate Theses and Dissertations
Emotion analysis is a branch of artificial intelligence and natural language processing focused on recognizing emotions hidden throughout various forms of digital data, including text, images, and multi-modal representations. In this dissertation, we present four published and planned works that investigate different methodologies for natural language analysis tasks using deep learning techniques. The first published work we present considers the task of identifying fake news using various text and emotion representations. We demonstrate that emotion representations combined with word embedding techniques can improve the accuracy of fake news classification. Our second published work further investigates the fake news classification task …
Hyperspectral Indicators And Characterization Of Glyphosate-Induced Stress In Common Lambsquarters (Chenopodium Album L.), Mario Andrés Soto Valencia
Hyperspectral Indicators And Characterization Of Glyphosate-Induced Stress In Common Lambsquarters (Chenopodium Album L.), Mario Andrés Soto Valencia
Graduate Theses and Dissertations
Hyperspectral sensing enables detection of herbicide stress in weeds, but practical use requires strategies for redundancy control, rating variability management, and evaluator bias mitigation. This thesis evaluates common lambsquarters (Chenopodium album) under glyphosate exposure, aiming to identify key wavelengths, construct vegetation indices, and improve injury modeling. Greenhouse experiments used dimensionality reduction methods (principal component analysis, Relief F, Bayesian discriminant analysis) to isolate 34 unique wavelengths from about 3,200 bands. Calibration data were collected 14 days after treatment (DAT) to support wavelength selection and model development, while data from 27 DAT were used for independent validation. Class comparisons across six statistically …
Beam Steering Control For A Small-Scale 5g Antenna Array, Omar Wagih Elkalesh
Beam Steering Control For A Small-Scale 5g Antenna Array, Omar Wagih Elkalesh
Graduate Theses and Dissertations
This thesis demonstrates the design, development, and validation of a full-scale adaptive beam steering control system of a small-scale 5G antenna array, designed and thoroughly evaluated with MATLAB Simulink. Overcoming the significant challenge of establishing strong wireless links in dynamic environments, the new system uses a new closed-loop control framework that can automatically detect the signal sources and automatically change the beam direction in real-time. The use of the adaptation is necessary to combat tracking errors that are caused by the mobility of the mobile users, environmental variations, as well as channel estimation errors, widespread in future wireless communication systems. …
Predicting Stock Price Movement With Llm-Enhanced Tweet Emotion Analysis, An Vuong
Predicting Stock Price Movement With Llm-Enhanced Tweet Emotion Analysis, An Vuong
Graduate Theses and Dissertations
Accurately predicting short-term stock price movement remains a challenging task due to the market’s inherent volatility and sensitivity to investor sentiment. In this thesis, we present a published paper that discusses a deep learning framework integrating emo- tion features extracted from tweet data with historical stock price information to forecast significant price changes on the following day. We utilize Meta’s LLaMA 3.1-8B-Instruct model to preprocess tweet data, thereby enhancing the quality of emotion features derived from three emotion analysis approaches: a transformer-based DistilRoBERTa classifier from the Hugging Face library and two lexicon-based methods using National Research Council Canada (NRC) resources. …
Optical Characterization Of Ge And Gesn Grown In Aspect Ratio Trapping Structures For Enhanced Emitter Performance, Abdulla Said Ali
Optical Characterization Of Ge And Gesn Grown In Aspect Ratio Trapping Structures For Enhanced Emitter Performance, Abdulla Said Ali
Graduate Theses and Dissertations
Silicon (Si) began dominating the electronics industry since 1960s, the dominance came due to its affordability and well developed fabrication processes. But when it comes to light emitting devices and photonics devices in general, the indirect bandgap of Si has caused many scientists to search for alternative semiconductor materials that can deliver better light emission, materials that can also improve wavelengths detection which is also very limited when it comes to Si, reduce losses and greater light amplification, all this while still being affordable. Despite these limitations, Si has been widely used in Complementary Metal Oxide Semiconductor (CMOS) manufacturing and …
Novel Approaches To Disinfecting Poultry Processing Wastewater For Reuse, Seth Olorunmijuwonlo Adesope
Novel Approaches To Disinfecting Poultry Processing Wastewater For Reuse, Seth Olorunmijuwonlo Adesope
Graduate Theses and Dissertations
Water is an essential resource used in poultry processing, generating large volumes of foodborne pathogen-rich wastewater posing treats to public health. Treating poultry processing wastewater (PPW) is crucial for safe water reuse and sustainable development. Conventional disinfection methods like aerobic digestion and chlorination, although effective, impose considerable operational cost and generate harmful by-products. Integrated recycling systems such as advanced oxidation processes (AOPs) which destroy micro-organisms through the generation of reactive oxygen species (ROS) present a promising opportunity for enhancing resources and sustainability. This study investigated the use of photo-electrochemical (PEC), specifically by combining electrochemical (EC) and photochemical (PC; Photosensitizer and …
Design And Development Of A Multi-Port Solid State Circuit Breaker Based On Half Bridge Sic Mosfets, Yannal Nawafleh
Design And Development Of A Multi-Port Solid State Circuit Breaker Based On Half Bridge Sic Mosfets, Yannal Nawafleh
Graduate Theses and Dissertations
This thesis investigates multi-port solid-state circuit breaker (M-SSCB) architectures that reduce steady-state conduction losses while preserving microsecond-class DC fault interruption and per-port selectivity. The proposed M-SSCB consolidates protection for several node interfaces into a single assembly with shared sensing, control, and a common energy-absorption branch. In normal operation, two electrically symmetric parallel semiconductor paths are established so each port’s current divides approximately in half; because conduction loss scales with current squared, the M-SSCB achieves ≈75% reduction in on-state loss relative to a conventional anti-series SiC path without increasing device count. During fault handling, the coordinated controller detects the local over-current, …
Automation And Upgrading Of Custom Cold Wall Uhv-Cvd Reactor For Group Iv Material Development, Alexander Golden
Automation And Upgrading Of Custom Cold Wall Uhv-Cvd Reactor For Group Iv Material Development, Alexander Golden
Graduate Theses and Dissertations
Group IV alloys have shown promising results for infrared optoelectronic applications where III-V materials are currently dominant. The III-V material system has vacancies that Group IV materials can fill, most importantly complementary metal oxide semiconductor (CMOS) process compatibility making quality devices much cheaper and widely available compared to the current state of the art. Silicon, being an indirect band gap Group IV material, has poor performance in optoelectronic applications but is the dominant material for most of the electronic industry. However, when silicon is alloyed or substituted with other group IV materials, these optoelectronic properties can be enhanced and, in …
Solar Powered Conservation: The Effects Of Solar Photovoltaic Facilities On Avian Community Composition, Michael Christopher Ferrara
Solar Powered Conservation: The Effects Of Solar Photovoltaic Facilities On Avian Community Composition, Michael Christopher Ferrara
Graduate Theses and Dissertations
The expansion of solar photovoltaic energy infrastructure is transforming landscapes worldwide. Increasingly, facilities are planted with native vegetation, yet how vegetation characteristics and landscape variables shape wildlife communities in solar facilities remains poorly understood. Because avian populations have been in decline and are sensitive to habitat changes, understanding how solar facilities influence avian communities is important. In Chapter 1, we used autonomous recording units, local vegetation measurements, and land use and land cover data to quantify how avian community occupancy is influenced by solar cover in solar facilities and comparable reference sites. We used a Bayesian multi-species occupancy model to …
Establishment Of Native Warm-Season Forages Using Organic Practices, Kolten Ray Wright
Establishment Of Native Warm-Season Forages Using Organic Practices, Kolten Ray Wright
Graduate Theses and Dissertations
Abstract Grassland agriculture is seen as a particularly sustainable form of agriculture. Many opportunities are known to use organic production methods or incorporate native warm-season grasses (NWSG) to accomplish both production goals and environmental or social outcomes. Environmental concerns have led some practitioners to question the use of organic methods to establish NWSG. As limited work has been accomplished in the northern bermudagrass belt, this project sought to compare organic establishment strategies for common NWSG species. A field trial conducted at the USDA ARS Dale Bumpers Small Farms Research Center in Booneville, AR found that NWSG establishment success in the …
Towards Vision-Brain Understanding At Scales: From Classical To Quantum Machine Learning Approaches, Xuan-Bac Nguyen
Towards Vision-Brain Understanding At Scales: From Classical To Quantum Machine Learning Approaches, Xuan-Bac Nguyen
Graduate Theses and Dissertations
In recent years, large-scale learning approaches such as unsupervised and self-supervised learning have revolutionized artificial intelligence. These methods enable machines to learn high-level representations without explicit human supervision, achieving remarkable success across vision, language, and multimodal tasks. However, such advances come at a cost—they rely on massive datasets, billions of parameters, and extensive computational resources. Despite these achievements, artificial systems still fall short of the remarkable learning efficiency of the human brain, which can infer, adapt, and generalize from limited experiences. This gap motivates a deeper exploration of how biological intelligence acquires knowledge and how these principles can inspire the …
Study And Simulation Of Model-Reference Adaptive Control Via The Heffron-Philips Model For Enhanced Power System Stability, Laila Ayman Dallol
Study And Simulation Of Model-Reference Adaptive Control Via The Heffron-Philips Model For Enhanced Power System Stability, Laila Ayman Dallol
Graduate Theses and Dissertations
Improving power transmission and quality has been an area of research interest over the past decades and was improved using renewable energy resources, mainly wind, and solar generation. Renewable energy penetration into power grids aims to replace some traditional synchronous generators, affecting the overall power system with reduced gas emissions that help with climate change and pollution issues. However, renewable generation in power systems ranging from microgrids to national grids is subjected to large disturbances that affect its transient stability, which is measured by its critical clearing time. As increased amounts of renewable generation connected to power systems have resulted …
Advanced Membrane Methods For Treatment Of Toxic Contaminants And Education Of Early-Career Researchers, Thomas Mckean Iii
Advanced Membrane Methods For Treatment Of Toxic Contaminants And Education Of Early-Career Researchers, Thomas Mckean Iii
Graduate Theses and Dissertations
Membrane technologies are attractive as they are linearly scalable and often require lower operating costs compared to other technologies. One area where they are particularly effective is the treatment of water contaminated with toxic substances. The simplicity of this removal mechanism provides reliable performance capable of meeting stringent removal requirements. However, membrane fouling is a major challenge that often limits their commercial viability. This research sought to investigate novel approaches to pretreatment and membrane modification to overcome fouling and high operating pressures. In addition, membrane separation processes can often be developed into simple yet educational experiments that are ideal for …
Unraveling Nucleation Mechanisms In Membrane Distillation: A Molecular Dynamics And Enhanced Sampling Approach, Nazanin Abbasi
Unraveling Nucleation Mechanisms In Membrane Distillation: A Molecular Dynamics And Enhanced Sampling Approach, Nazanin Abbasi
Graduate Theses and Dissertations
Membrane distillation offers a promising route for desalination but remains limited by salt scaling, where mineral crystals nucleate and grow in concentrated brines. To inform strategies that mitigate scaling, this thesis investigates homogeneous nucleation in supersaturated aqueous NaCl solutions using molecular dynamics and enhanced sampling techniques. Several collective variables (CVs) are tested to capture the early stages of ion aggregation and crystal formation, including ion–ion coordination number, dehydration, and bond orientational order parameters Q₄ and Q₆. Enhanced sampling techniques, such as metadynamics and umbrella sampling, are employed to overcome the high free energy barriers associated with the formation of critical …
Contextual Embedding Using Machine Learning For Cybersecurity: Access Control And Application, Thanh Bui
Contextual Embedding Using Machine Learning For Cybersecurity: Access Control And Application, Thanh Bui
Graduate Theses and Dissertations
Access control is a well-established challenge in cybersecurity, with significant research focused on enhancing system autonomy and accuracy across various scenarios. Access control rules can be designed based on users’ roles, attributes, or relationships requesting access to specific resources. However, despite their benefits, these models still require human oversight. As systems expand and grow, it becomes increasingly complex for administrators to maintain precise access control rules, often necessitating extensive system updates or even a complete overhaul. This dissertation introduces a novel approach that leverages contextual embedding for user information to enable the system to autonomously authorize user requests for resources. …
Effect Of Peracetic Acid Dip Frequency On The Quality And Functional Properties Of Non-Marinated And Marinated Broiler Tenderloins, Joaquin Jose Esquivel Vergara
Effect Of Peracetic Acid Dip Frequency On The Quality And Functional Properties Of Non-Marinated And Marinated Broiler Tenderloins, Joaquin Jose Esquivel Vergara
Graduate Theses and Dissertations
The poultry industry continues to balance the need for effective antimicrobial interventions with the preservation of meat quality. Among the most widely used antimicrobial agents, peracetic acid (PAA) has proven effective for reducing foodborne pathogens in poultry products. However, excessive or repeated exposure to PAA can influence meat functionality by altering protein structure, color, and water-holding capacity. Therefore, the broad objective of this study was to evaluate the effect of PAA dip frequency and post-treatment marination timing on the physicochemical and functional quality of broiler tenderloins (Pectoralis minor), in order to provide processing insights that optimize both microbial safety and …
Using Color And Fluorescent Spectrometry As A New Rapid Cleaning Verification Method In Poultry Processing Plants, Clark Griscom
Using Color And Fluorescent Spectrometry As A New Rapid Cleaning Verification Method In Poultry Processing Plants, Clark Griscom
Graduate Theses and Dissertations
The poultry industry is expected to be growing at 3% in the total global market with the U.S. being the largest producer of poultry meat. Poultry processing plants are expected to produce 140 birds per minute with the potential of up to 175 birds per minute to meet the market demand. With the growing market and need for faster production, maintaining food safety needs to be a priority to ensure the safety of consumers. Over 9.9 million foodborne illness cases are reported each year in the United States. A change in food safety is needed, and one area lacking is …
When The Grid Goes Dark: A Digital Forensics Study Of Industrial Control System Cyberattacks, Katie Kettler
When The Grid Goes Dark: A Digital Forensics Study Of Industrial Control System Cyberattacks, Katie Kettler
Graduate Theses and Dissertations
Industrial Control Systems (ICS) and Operational Technology (OT) maintain the grid, ensure water safety, and keep transportation running. Because they influence nearly every aspect of daily life, these systems have become prime targets for cyberattacks. The need for this research arises from the fact that when ICS and OT systems are compromised, the consequences go beyond data loss, and they can directly disrupt communities and endanger public safety. This thesis introduces digital forensics fundamentals and explains how investigations in ICS environments differ from those in traditional IT environments. This work then examines major attacks, including Stuxnet, the Ukrainian Grid Attacks …
Volume Status Detection With Integral Pulse Frequency Modulation Model Of Peripheral Venous Pressure, Jeremiah Rhys Wimer
Volume Status Detection With Integral Pulse Frequency Modulation Model Of Peripheral Venous Pressure, Jeremiah Rhys Wimer
Graduate Theses and Dissertations
This thesis studies the effectiveness of utilizing a modified integral pulse frequency modulation (IPFM) algorithm to synthesize peripheral venous pressure (PVP) waveforms for the detection of several physiological conditions using logistic regression. PVP waveforms are collected from 18 human patients and 4 porcine subjects. Human data are used to train models for determining the hypovolemic status of the patient, while the porcine data are used to train models for determining level of anesthesia and detecting internal hemorrhaging. In the human dataset, the waveforms collected from the 18 patients are classified into two groups according to serum chloride levels: resuscitated (≥100 …
Two Topics In Survival Analysis: Restricted Distance Covariance Test For Non-Proportional Hazard And A New Estimation For Dropout Rate, Ruizhe Yin
Graduate Theses and Dissertations
When treatment effects change over time, standard statistical methods, such as the log-rank test and the Cox proportional hazards model, may give misleading results. This dissertation presents the restricted distance covariance (rdcov) test, a nonparametric method that compares survival curves between groups within a chosen study period [0, τ] using right censored data. The statistic measures the dependence between pre-specified group labels and survival times using pairwise distances from Kaplan-Meier estimates. Our method does not rely on the proportional hazards assumption, and it equals zero only when survival functions are identical across groups. Thus, this test can be applied to …
Design Of Phase Shifter And True Time Delay Gan Mmics For High-Temperature Ku-Band Applications, Michael Lee Thompson
Design Of Phase Shifter And True Time Delay Gan Mmics For High-Temperature Ku-Band Applications, Michael Lee Thompson
Graduate Theses and Dissertations
This thesis presents the design, implementation, and high-temperature characterization of Gallium Nitride (GaN) monolithic microwave integrated circuits (MMICs) developed for beamforming and phased-array systems operating in the Ku-band (12-14 GHz). Two integrated circuits were designed: a 3-bit digital phase shifter and a 3-bit true time delay (TTD), both optimized for high linearity, low insertion loss, low phase error, and stable operation at elevated temperatures up to 300°C. Developing both a phase shifter and a TTD enabled a direct comparison of their beamforming performance and the evaluation of beam squint effects over frequency, a critical factor in wideband array design. The …
Extending Touch: Investigating Sensorimotor Integration, Cognitive Workload, And Presence With Neuro-Haptic Feedback In Virtual Reality, Aliyah Khadijah Shell
Extending Touch: Investigating Sensorimotor Integration, Cognitive Workload, And Presence With Neuro-Haptic Feedback In Virtual Reality, Aliyah Khadijah Shell
Graduate Theses and Dissertations
Sensory feedback from the hand is fundamental for the coordination of fine motor skills and overall sensorimotor function. Impaired somatosensation during task execution has been associated with the development of inaccurate motor plans, which can hinder motor learning. Virtual Reality (VR) has emerged as a promising tool for motor rehabilitation; however, most VR-based interventions overlook the critical role of tactile feedback in motor control. The absence of touch feedback, which is integral to conventional rehabilitation and training, may limit the full therapeutic potential of VR. Integrating functionally relevant neurostimulation based haptic feedback (neuro-haptic feedback) into VR-based interventions may enhance functional …