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Graduate Theses and Dissertations

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Series Resonant Converters With Medium Voltage Sic Mosfets For Electric Aircraft Applications, Xinyuan Du Dec 2025

Series Resonant Converters With Medium Voltage Sic Mosfets For Electric Aircraft Applications, Xinyuan Du

Graduate Theses and Dissertations

To develop high-performance high- power-density MV power converters, the emerging silicon carbide (SiC) devices are more attractive than their silicon (Si) counterparts, since the fast switch frequency brought by the SiC can effectively reduce the volume and weight of the filter components and thus increase the converter power density. From the converter topology perspective, with the MV dc distribution, the single stage isolated dc/dc converter are suitable for next-generation electric aircraft system due to soft switching and high power density. In this work, comprehensive static and dynamic characterizations were conducted for the latest 6.5 kV silicon carbide (SiC) MOSFETs from …


Synthetic Dataset For Understanding Negation In Text-Guided Image Editing, Nhat-Tan Bui Dec 2025

Synthetic Dataset For Understanding Negation In Text-Guided Image Editing, Nhat-Tan Bui

Graduate Theses and Dissertations

Negation is a fundamental linguistic concept used by humans to convey information that they do not desire. Despite this, minimal research has focused on negation within text-guided image editing. This lack of research means that vision-language models (VLMs) for image editing may struggle to understand negation, implying that they struggle to provide accurate results. One barrier to achieving human-level intelligence is the lack of a standard collection by which research into negation can be evaluated. This thesis presents the first large-scale dataset, Negative Instruction (NeIn), for studying negation within instruction-based image editing. Our dataset comprises 366,957 quintuplets, i.e., source image, …


Implementation Of A Three-Port Solar Converter With A Battery Energy Storage System, Maison Christopher Phipps Dec 2025

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™ …


Programmable Network Approaches To Resilience And Security In Phasor Measurement Unit Networks, Zhiyao He Dec 2025

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 …


Discriminative And Generative Video Modeling, Anh Pha Nguyen Dec 2025

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 …


Increasing Soil Health In Zero-Grade, Flood-Irrigated Rice In Eastern Arkansas, Hannah Elizabeth Vickmark Dec 2025

Increasing Soil Health In Zero-Grade, Flood-Irrigated Rice In Eastern Arkansas, Hannah Elizabeth Vickmark

Graduate Theses and Dissertations

In an effort to build and maintain soil health and sequester soil C, many producers and researchers are turning towards regenerative management practices in agricultural systems, such as reduced tillage or no-tillage (NT), the implementation of winter cover crops (CC), and the use of organic or green manures, such as biochar. However, little research is being conducted on the long-term soil health and agronomic benefits of these practices in a flood-irrigated rice (Oryza sativa L.) production system. Three replications of seven treatment combinations were applied to 6.1 x 30.5 m rice plots. Baseline soil health properties were quantified at six …


Optical Characterization Of Ge And Gesn Grown In Aspect Ratio Trapping Structures For Enhanced Emitter Performance, Abdulla Said Ali Dec 2025

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 …


Privacy Protection In Cloud-Based Biometric Systems, Yatish Reddy Dubasi Dec 2025

Privacy Protection In Cloud-Based Biometric Systems, Yatish Reddy Dubasi

Graduate Theses and Dissertations

The widespread adoption of server-based biometric authentication systems, often hosted in the cloud, has introduced significant privacy risks. While these systems offer convenience, they require storing sensitive biometric templates on remote servers, creating a high-value target for adversaries. Unlike passwords, compromised biometric data is immutable and cannot be reissued, leading to an irreversible loss of privacy. This threat is exacerbated by template inversion attacks, which can reconstruct a user's original biometric trait (e.g., a face image) from its stored feature vector. This dissertation addresses these critical privacy challenges by designing, implementing, and evaluating a suite of novel frameworks for privacy-preserving …


Ecological Elemental Homeostasis And Stoichiometric Shifts: Biotic Responses To Ionic And Viral Stress, Samuel Anthony Tooru Dias Dec 2025

Ecological Elemental Homeostasis And Stoichiometric Shifts: Biotic Responses To Ionic And Viral Stress, Samuel Anthony Tooru Dias

Graduate Theses and Dissertations

Anthropogenic activities are reshaping the elemental composition of freshwater ecosystems, often creating stoichiometric imbalances that influence the growth, physiology and interactions of aquatic organisms. Ecological stoichiometric theory (EST) provides a framework for examining these changes by linking organismal elemental regulation to broader ecosystem processes. While traditionally focused on elements, such as carbon (C), nitrogen (N), and phosphorus (P), emerging stressors highlight the need to expand this framework to be more elementally inclusive for the examination of novel interactions. My dissertation integrates abiotic (salinization) and biotic stressors (viral infection) into an EST framework to evaluate how these factors alter elemental regulation …


Establishment Of Native Warm-Season Forages Using Organic Practices, Kolten Ray Wright Dec 2025

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 …


Contextual Embedding Using Machine Learning For Cybersecurity: Access Control And Application, Thanh Bui Dec 2025

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. …


Unraveling Nucleation Mechanisms In Membrane Distillation: A Molecular Dynamics And Enhanced Sampling Approach, Nazanin Abbasi Dec 2025

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 …


Advanced Membrane Methods For Treatment Of Toxic Contaminants And Education Of Early-Career Researchers, Thomas Mckean Iii Dec 2025

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 …


Effect Of Peracetic Acid Dip Frequency On The Quality And Functional Properties Of Non-Marinated And Marinated Broiler Tenderloins, Joaquin Jose Esquivel Vergara Dec 2025

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 Dec 2025

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 Dec 2025

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 Dec 2025

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 …


Design Of Phase Shifter And True Time Delay Gan Mmics For High-Temperature Ku-Band Applications, Michael Lee Thompson Dec 2025

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 …


Next-Generation Salmonella Inactivated Vaccine Platforms And Phytobiotic-Modulated Immune Responses In Poultry, Santiago Uribe Diaz Dec 2025

Next-Generation Salmonella Inactivated Vaccine Platforms And Phytobiotic-Modulated Immune Responses In Poultry, Santiago Uribe Diaz

Graduate Theses and Dissertations

Here, a comprehensive understanding of immune responses triggered by either a multimeric CD40 receptor-agonistic DNA aptamer-based or mannosylated chitosan-based Salmonella Enteritidis inactivated vaccine platforms, along with phytobiotic supplementation as an immune modulatory strategy in response to Salmonella lipopolysaccharides, is presented. This dissertation supports the development of next-generation Salmonella vaccine platforms that simultaneously stimulate both protective cell-mediated and humoral immune responses, while indicating the potential immunomodulatory effects of phytobiotics supplementation to reduce the immunological impact of Salmonella lipopolysaccharides in chickens. The first chapter describes that both vaccine platforms administered in broiler chickens initiated local inflammatory responses, recruiting heterophils and macrophages from …


Micro-Greens, Not Micro-Yellows: Evaluating Dehydration-Based Preservation Techniques For Reducing Foodborne Pathogens And Quality Preservation On Microgreens, Travis S. Sananikone Dec 2025

Micro-Greens, Not Micro-Yellows: Evaluating Dehydration-Based Preservation Techniques For Reducing Foodborne Pathogens And Quality Preservation On Microgreens, Travis S. Sananikone

Graduate Theses and Dissertations

Microgreens are increasingly popular among consumers due to their high nutritional value. However, their limited shelf-life remains a significant challenge. To extend their usability, small-scale growers increasingly apply home preservation methods like warm air drying or freeze-drying. However, the effects of these methods on common foodborne pathogens are not well understood. Radish and alfalfa microgreens were inoculated with cocktails of Salmonella enterica, Escherichia coli O157:H7, and Listeria monocytogenes 4b (ca. 8.0 log CFU/g). Treatments included dehydration in a commercial dehydrator, freeze-drying (-20°C, 24 h), and convective drying in an oven (60°C for 4 h), and convective drying in an oven …


Effects Of Injectable Trace Mineral Timing On Calf Performance And Health Indicators, Marie E. Goulais Dec 2025

Effects Of Injectable Trace Mineral Timing On Calf Performance And Health Indicators, Marie E. Goulais

Graduate Theses and Dissertations

One hundred and fourteen calves (average BW= 224kg ± 89kg) were utilized to evaluate the effects of injectable trace mineral (ITM) administration on calf performance and health when administered pre-weaning and at weaning. Calves were blocked by sex, stratified by age, and randomly assigned to one of the following treatment groups: 1) no ITM injection (CON), 2) ITM administered 28 d before weaning (PW), or 3) ITM administration at weaning (WEAN). Calves were vaccinated against respiratory pathogens on D-28 and D0. At weaning, cattle were transported to a local auction market, held overnight and returned the following morning. Body weight …


Just Because They Can, Doesn’T Mean They Will: College Students’ Use And Non-Use Of Alcohol Protective Behavioral Strategies, Patrick Walter Mcclain Dec 2025

Just Because They Can, Doesn’T Mean They Will: College Students’ Use And Non-Use Of Alcohol Protective Behavioral Strategies, Patrick Walter Mcclain

Graduate Theses and Dissertations

College students engage in high levels of alcohol consumption, which can increase their risk of alcohol-related negative consequences. To address this, researchers developed Alcohol Protective Behavioral Strategies (APBS), which are actions that students can take before or while drinking to limit their alcohol use and/or reduce their likelihood of experiencing drinking harms. However, students’ APBS use could depend on their perceived usefulness of these strategies, whether they engage in high-risk drinking, or both. Therefore, the present study aims to investigate: (1) what percentage of students (a) perceive each APBS as useful and (b) implement the APBS they find useful, (2) …


Understanding Outer Solar System Ice Composition Through Impact Processes: Simulations And Hydrates, Jill Rebecca Mcdonald Dec 2025

Understanding Outer Solar System Ice Composition Through Impact Processes: Simulations And Hydrates, Jill Rebecca Mcdonald

Graduate Theses and Dissertations

This work concerns solar system ices, particularly water ice and clathrate hydrates. Water ice is abundant as a mineral in the outer parts of the solar system, providing source material for the formation of clathrates. We explored constituents through a combination of numerical modeling and laboratory experiments. Understanding the differences and similarities between these materials can shed light on planetary habitability, composition, and evolution. Chapter one contains relevant background information. This chapter introduces the ices that will be studied and gives insight into the locations of interest within our solar system. It also explains the mechanics of impact cratering processes …


Fungicidal Management Of Spring Dead Spot Using Improved Modeling And Application Strategies, Michael Vincent Battaglia Dec 2025

Fungicidal Management Of Spring Dead Spot Using Improved Modeling And Application Strategies, Michael Vincent Battaglia

Graduate Theses and Dissertations

Spring dead spot (SDS) is a destructive disease of bermudagrass (Cynodon Rich. spp.) in parts of the world that experience winter dormancy. Fungicides are often necessary to properly manage SDS, and significant research has been conducted to improve fungicidal effectiveness. Several studies were conducted with the objectives of improving fungicide application timing, method of fungicide application, and long-term fungicidal efficiency. In the fungicide application study, a cooling degree-day (CDD) model based on soil temperatures was developed. The CDD model showed that isofetamid was highly effective against SDS during a wide application window in autumn, while tebuconazole was inconsistently effective and …


Assessing Native Tallgrass Prairie Species As Main Roadside Vegetation In Arkansas, Sarah Paschal Dec 2025

Assessing Native Tallgrass Prairie Species As Main Roadside Vegetation In Arkansas, Sarah Paschal

Graduate Theses and Dissertations

Tallgrass prairies are among the most endangered ecosystems in North America, with Arkansas having lost over 99% of its native grasslands. This research evaluated the potential for using native tallgrass prairie species in Arkansas roadside vegetation. Two field experiments were conducted from 2022 to 2024. The first assessed seven native seed mixtures at three roadside locations (Clarksville, Huntsville, and Newport). Seed mixture composition significantly influenced establishment outcomes, with early-establishing forbs such as black-eyed Susan, partridge pea, and Illinois bundleflower performing well, though establishment varied by location. A second trial compared planting date (Autumn, Winter, Spring) and planting method (broadcast, drill …


Supporting At-Risk Students Through Alternative Education: A Case Study On Reintegration, Behavior, And Stakeholder Perceptions At Sharpie Academy, Bryan O'Neal Dec 2025

Supporting At-Risk Students Through Alternative Education: A Case Study On Reintegration, Behavior, And Stakeholder Perceptions At Sharpie Academy, Bryan O'Neal

Graduate Theses and Dissertations

This dissertation presents a mixed-methods case study examining the effectiveness of Sharpie Academy, an alternative education program within the Chalkboard Champions School District. The study investigated three central research questions: (1) How does participation in the alternative learning environment at Sharpie Academy influence students' behavior upon reintegration into the traditional education setting? (2) What are the perceptions of parents, teachers, and community members regarding the program's outcomes? (3) How do these perceptions influence stakeholder support for the academy? Data was collected from 121 participants, including 43 students and 78 adult stakeholders, using participant observation, semi-structured interviews, surveys, and document analysis. …


Bridging The Gap: Enhancing Institutional Support For Adjunct Faculty In Rural Community Colleges, Emily Joleen Mason Dec 2025

Bridging The Gap: Enhancing Institutional Support For Adjunct Faculty In Rural Community Colleges, Emily Joleen Mason

Graduate Theses and Dissertations

Adjunct faculty constitute approximately 70% of the academic workforce in U.S. higher education, yet they often face challenges related to professional isolation, limited institutional support, and insufficient onboarding. This qualitative study explores how institutional connectedness influences adjunct faculty retention at a rural community college in the Midwest. Using a phenomenological approach, the research investigates the lived experiences of adjunct faculty, focusing on onboarding processes, professional development opportunities, and institutional culture. Findings highlight the critical role of structured onboarding, mentorship, and continuous professional development in fostering engagement and retention among adjunct faculty. The study underscores the importance of inclusive institutional practices …


Free Radical Reactions Of Electron Rich Alkenes, David A. May Jr Dec 2025

Free Radical Reactions Of Electron Rich Alkenes, David A. May Jr

Graduate Theses and Dissertations

Radical reactions have known for over a century but have only been thought of as useful synthetic strategies for the last 70 years. During this period, much work has been done to develop theoretical explanations for their reactivity and modes of termination, resulting in them becoming a fundamental type of organic reaction in academia and industry. Previous studies by the McIntosh group have shown that a radical [1,3]-Rearrangement occurs when N-substituted pyridines are heated. Here, the scope of this new reaction is expanded to include polycyclic pyridines including neocuproine (2,9-dimethylphenanthroline) and 2-methylquinoline while also expanding the range of reactions available …


Emotion Analysis And Neural Language Models For Classification, Andrew Mackey Dec 2025

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 Dec 2025

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 …