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2025

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Examining The Relationship Between Organizational Citizenship Behaviors (Ocb) And Student Achievement In K-12 High Poverty Schools, Trayvonia S. Duhe Dec 2025

Examining The Relationship Between Organizational Citizenship Behaviors (Ocb) And Student Achievement In K-12 High Poverty Schools, Trayvonia S. Duhe

LSU New Orleans Theses and Dissertations

This quantitative correlational study examined the relationship between teacher OCB and student achievement in high-poverty public and charter schools in Louisiana, where 71% of students are economically disadvantaged. 96 ELA and math teachers participated, completing the Organizational Citizenship Behavior Scale alongside their classroom-level LEAP 2025 results. Guided by Social Exchange Theory, the study also explored the association between OCB and teachers’ perceptions of organizational justice. Findings indicated that teachers reported moderate engagement in OCB; however, the relationship between OCB and student achievement was weak, positive, and non-significant. This suggests that while teachers consistently engage in discretionary behaviors that support school …


Dynamic Response Control And Vibration Mitigation Of Two-Degree-Of-Freedom Structures Using Combined Variable Inertia Rotational Mechanism And Tuned Mass Damper System, Marah Abedel Majid Dec 2025

Dynamic Response Control And Vibration Mitigation Of Two-Degree-Of-Freedom Structures Using Combined Variable Inertia Rotational Mechanism And Tuned Mass Damper System, Marah Abedel Majid

LSU New Orleans Theses and Dissertations

Dynamic Response Control and Vibration Mitigation of Two-Degree-of-Freedom Structures Using Combined Variable Inertia Rotational Mechanism and Tuned Mass Damper System Rotational inertia mechanisms provide innovative methods to develop vibration response for structures subjected to dynamic loads. This study investigates a two-degree-of-freedom (2DOF) structural system with Variable Inertia Rotational Mechanisms (VIRMs) and a Tuned Mass Damper (TMD) as a combined passive control system. The governing nonlinear equations of motion were developed using a mathematical modeling framework and numerically solved for free, harmonic, and broadband excitation. Comparative assessments between Fixed Inertia Rotational Mechanisms (FIRM), VIRM, and combined VIRM–TMD configurations demonstrate that the …


Applications Of Machine Learning In Gravitational-Wave Research With Current Interferometric Detectors, Elena Cuoco, Marco Cavaglià, Ik Siong Heng, David Keitel, Christopher Messenger Dec 2025

Applications Of Machine Learning In Gravitational-Wave Research With Current Interferometric Detectors, Elena Cuoco, Marco Cavaglià, Ik Siong Heng, David Keitel, Christopher Messenger

Physics Faculty Research & Creative Works

This article provides an overview of the current state of machine learning in gravitational-wave research with interferometric detectors. Such applications are often still in their early days but have reached sufficient popularity to warrant an assessment of their impact across various domains, including detector studies, noise and signal simulations, and the detection and interpretation of astrophysical signals. In detector studies, machine learning could be useful to optimize instruments like LIGO, Virgo, KAGRA, and future detectors. Algorithms could predict and help in mitigating environmental disturbances in real time, ensuring detectors operate at peak performance. Furthermore, machine-learning tools for characterizing and cleaning …


Characterizing Stellar Flares On Low-Mass Stars Tic 144217628 And Proxima Centauri Using Transiting Exoplanet Space Satellite (Tess) Optical Data, Charles Edward Holloway Dec 2025

Characterizing Stellar Flares On Low-Mass Stars Tic 144217628 And Proxima Centauri Using Transiting Exoplanet Space Satellite (Tess) Optical Data, Charles Edward Holloway

Graduate Theses and Dissertations

Low-mass stars account for more than 70% of stars within our galaxy. Their ob?servational interest can be attributed to their smaller radius and luminosity, making them ideal for detecting terrestrial planets inside their habitable zones. These magnetically active stars produce frequent stellar flaring events that can impact the atmospheric composition of nearby planets and interfere with the prebiotic processes for carbon-based life. Using TESS optical data, I have detected, measured astrophysical properties, and modeled the behavior of 44 flares from two low-mass stars: TIC 144217628 and Proxima Centuari. Given similar observational periods, Proxima Cen has shown to produce larger amplitudes …


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 …


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 …


Design And Optimization Of High-Frequency Medium-Voltage Dual Active Bridge Dc/Dc Converter Using Sic Device, Hui Cao Dec 2025

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 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 …


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 …


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 …


Automation And Upgrading Of Custom Cold Wall Uhv-Cvd Reactor For Group Iv Material Development, Alexander Golden Dec 2025

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 …


Evidence Of Backwater Morphodynamics In Stratigraphy On Earth And Mars: Implications For Ancient Mars, Cory Mitchell Hughes Dec 2025

Evidence Of Backwater Morphodynamics In Stratigraphy On Earth And Mars: Implications For Ancient Mars, Cory Mitchell Hughes

Graduate Theses and Dissertations

Geologic evidence indicates that liquid water once flowed in abundance across the martian surface. For this reason, in the search for evidence of extraterrestrial life, Mars represents a prime target for scientific inquiry. River systems encode climatic and environmental signals in their deposits on Earth and Mars, often in fan-shaped landforms (e.g., alluvial fans, river deltas, etc.). Distal fan-shaped deposits (i.e., river deltas), in particular, act as a relatively high-fidelity record of dynamic geologic processes. As such, NASA frequently sends rovers to locations on Mars’ surface with hypothesized river deltas (e.g., Perseverance and Jezero crater). Problematically, there are many different …


Solar Powered Conservation: The Effects Of Solar Photovoltaic Facilities On Avian Community Composition, Michael Christopher Ferrara Dec 2025

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 …


Study And Simulation Of Model-Reference Adaptive Control Via The Heffron-Philips Model For Enhanced Power System Stability, Laila Ayman Dallol Dec 2025

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 …


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 …


Novel Radical Chemistry Of Electron-Rich Double Bonds, Claire Allyson Beard Dec 2025

Novel Radical Chemistry Of Electron-Rich Double Bonds, Claire Allyson Beard

Graduate Theses and Dissertations

This work delves into the reactivity of nucleophilic N-heterocyclic carbenes (NHCs) and their ability to form electron-rich alkene intermediates, which can undergo various chemical transformations depending on the nature of the electrophile. Initial reports by Hahn disclosed the NHC promoted radical nature of electron-rich N,N’-benzyltetraazafulvalenes, which led to 2,2’- biimidazoles. We found that N-aryl substituted pyridinium salts also underwent rapid a similar NHC promoted dimerization when exposed to a base, producing 2,2’-bipyridyls. This is likely due to the adept radical nature of the bipyridinylidene intermediate for C-Naryl bond scission. We have also uncovered an unprecedented C-N bond scission of Breslow-like …


Multiple Aspects Of Environmental Temperature Have Complex Interactions With Avian Parental Behavior To Influence Offspring Outcomes, William H. Kirkpatrick Dec 2025

Multiple Aspects Of Environmental Temperature Have Complex Interactions With Avian Parental Behavior To Influence Offspring Outcomes, William H. Kirkpatrick

Graduate Theses and Dissertations

Anthropogenic climate change is projected to shift not only average temperatures across the globe, but also the amount of thermal variation experienced in the natural environment. Exposure to shifts in averages and a wider range of thermal experiences will cause shifts in wildlife behavior. In avian species, behaviors exhibited during reproduction have implications for the well-being of their offspring. Here, I explore specific incubation behaviors in four species: Scaled Quail (Callipepla squamata), Northern Bobwhite Quail (Colinus virginianus), Tree Swallows (Tachycineta bicolor), and Eastern Bluebirds (Sialia sialis). I examined constancy, or the percentage of time on the nest, and off-bout duration, …


Ring-Opening And Monofunctionalization Study On Spiro Cyclic Aminals And N, O-Acetals System Via Nitrogen-Centered Radical Intermediates, Chujun Zhou Dec 2025

Ring-Opening And Monofunctionalization Study On Spiro Cyclic Aminals And N, O-Acetals System Via Nitrogen-Centered Radical Intermediates, Chujun Zhou

Graduate Theses and Dissertations

The nitrogen-centered radical has been drawing increasing attention among researchers. Radical polarity is one of the key factors in studying nitrogen-centered radicals’ reactivity, and the functional groups attached to the nitrogen atom are of vital importance. Among different types of nitrogen-centered radicals, aminium radical and metal aminium radical are electrophilic due to the positive charge on the intermediate. The sulfonamide radical, amidyl radical, and cyanide amine radical are also electrophilic since the nitrogen is adjacent to electron electron-withdrawing group. The neutral amino radical, iminyl radical, masked nitrogen radical are nucleophilic because of the electron-donating groups. After classifying the nitrogen-centered radical, …


Expression, Purification And Characterization Of Full Length Tdp-43, Danya Abouzaid Dec 2025

Expression, Purification And Characterization Of Full Length Tdp-43, Danya Abouzaid

Honors Theses

TAR DNA-binding protein 43 (TDP-43) is a 43 kDa RNA-binding protein linked to several neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD), and Alzheimer’s disease. 5-7,28,30,33 Studying full-length TDP-43 has been difficult because of its intrinsic instability and tendency to aggregate.19,25,28,33,36 In this study, we focused on overcoming the difficulties to express full-length TDP-43 in E. coli recombinantly. We focused on expressing full-length TDP-43 as a fusion construct with a maltose-binding protein (MBP) to improve solubility and stability. Our strategy was to purify TDP-43-MBP fusion and make biomolecular condensates with RNA before cleaving the tag with thrombin protease. …


Dolphins ‘Orient-Against-Current’: Foraging In Dredged Channels, Eliza M.M. Mills, Sarah Piwetz, Dara N. Orbach Dec 2025

Dolphins ‘Orient-Against-Current’: Foraging In Dredged Channels, Eliza M.M. Mills, Sarah Piwetz, Dara N. Orbach

Marine Science

Bottlenose dolphins (Tursiops sp.) are opportunistic foragers with global distributions that utilize diverse feeding tactics based on environmental factors, habitat features, prey behavior, group dynamics, and genetics. We describe a unique foraging tactic regularly observed in the confluence of dredged shipping channels with high anthropogenic disturbance, and explore potential abiotic (temporal, tidal, habitat) drivers of the behavior. A shore-based digital theodolite was used from 2021 to 2022 to observe common bottlenose dolphins (T. truncatus) foraging within a current in a technique we term Orient-Against-Current (OAC). During OAC, dolphins position themselves facing into the flow of a current, swimming at a …


Exploring The Relationship Between Secondary Student Perceptions Of Teacher Involvement And Student Academic Success In Online Social Studies Courses, Thomas Matthew Herrington Dec 2025

Exploring The Relationship Between Secondary Student Perceptions Of Teacher Involvement And Student Academic Success In Online Social Studies Courses, Thomas Matthew Herrington

Electronic Theses and Dissertations

The rapid growth of online learning in secondary education has highlighted the need to better understand factors that contribute to student success. While considerable research has examined online learning at the postsecondary level and in state-tested subjects, little attention has been given to social studies courses. This qualitative study explored the relationship between secondary students’ perceptions of teacher involvement and their academic success in asynchronous online social studies courses. Participants included 22 students from two accredited high schools in Mississippi, one fully online and one traditional brick-and-mortar school, both of which offered asynchronous social studies courses approved by the state …


The Impact Of State-Mandated High-Stakes Standardized Testing On The Job Satisfaction Of Third-Grade Reading Teachers In Mississippi, Jenny Kate Ernst Dec 2025

The Impact Of State-Mandated High-Stakes Standardized Testing On The Job Satisfaction Of Third-Grade Reading Teachers In Mississippi, Jenny Kate Ernst

Electronic Theses and Dissertations

This qualitative study examined how state-mandated standardized testing influences the job satisfaction of current and former third-grade reading teachers in Mississippi. Guided by Self-Determination Theory, Herzberg’s Two-Factor Theory, and the Job Demands-Resources Model, the research explored how accountability pressures shape teachers’ motivation, emotional well-being, and instructional autonomy. Data were collected through an open-ended online survey of current and former Mississippi third-grade reading teachers. Analysis of responses revealed four central themes: emotional strain and burnout, loss of autonomy and creativity, impact on instructional practices, and student impact. Findings indicated that teachers perceive standardized testing as a major source of stress that …


Design And Prototyping Of An Acoustic Positioning System For Gps-Denied Environment, Harley Hogan Garrett Dec 2025

Design And Prototyping Of An Acoustic Positioning System For Gps-Denied Environment, Harley Hogan Garrett

Electronic Theses and Dissertations

Finding the placement of sensors is known as sensor localization, and is a necessary task to ensure that a network is capable of array processing operations, such as direction of arrival measurements. This thesis proposes a method to perform sensor localization for a wireless sensor network using acoustics. Each sensor is equipped with a microphone, speaker, and processor. Using these, the proposed system is able to find the distance between each sensor and later the geometry of the network. A series of optimizations help reduce error and improve the final accuracy of the system to within 6.5 cm. The proposed …


Observations And Analyses Of Heptane Fuel Jets Under Supercritical Conditions In Microgravity, Zoë Isabella Alexander Dec 2025

Observations And Analyses Of Heptane Fuel Jets Under Supercritical Conditions In Microgravity, Zoë Isabella Alexander

All Theses

Advanced combustion engines are trending towards high-pressure operations to increase the efficiency and power of the engines. Injecting liquid fuel at subcritical temperature into a supercritical ambient temperature and pressure environment is a key challenge in many practical combustion engines. This process involves fuel transitioning from subcritical to supercritical conditions, leading to combustion through jet atomization and droplet formation. Due to the complexity of this problem, the current research divided the process into two areas focused on the combustion of a single droplet and the fundamentals of the liquid transition in a jet stream in an inert environment at supercritical …


Stochastic Functional Data-Driven Models For Real-Time Battery Health Forecasting Under Dynamic Operating Conditions, Joshua Owusu Dec 2025

Stochastic Functional Data-Driven Models For Real-Time Battery Health Forecasting Under Dynamic Operating Conditions, Joshua Owusu

Electronic Theses and Dissertations

This thesis provides an effective statistical model to predict the real-time state of lithium-ion batteries for reliable Battery Management Systems (BMS). It highlights battery data (voltage, current, temperature) as smooth functional curves. The principal method demonstrates diminishing trends to health outcomes like State of Health (SoH) and Remaining Useful Life (RUL) by employing Functional Principal Component Analysis (FPCA) and Bayesian Functional Linear Models (FLMs). The primary objective is to figure out how uncertain forecasts are. Simulations demonstrate that the highest accuracy (lowest MSE) is achieved through low noise levels along with large sample sizes. The final system provides a highly …


Soil Characterization With Proximal Geophysics, Sophia M. Becker Dec 2025

Soil Characterization With Proximal Geophysics, Sophia M. Becker

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

High quality soil data is crucial for addressing numerous threats to human well-being such as water scarcity, food insecurity, and intensified natural disasters. True soil property values are determined by analyzing soil samples in a laboratory, but soil sampling is often expensive and time-consuming. Some in-field point sensors and remote sensing products are available to measure soil properties, but they have inherent limitations in measurement extent and resolution. Geophysical methods can fill the measurement scale gap between point measurements and remote sensing products, but various research questions remain open. This dissertation aims to advance understanding of geophysics-derived soil property measurements …


An Integrated Modeling Framework To Evaluate Circularity Of The Corn–Water–Ethanol–Beef Nexus, Heydi Han Dec 2025

An Integrated Modeling Framework To Evaluate Circularity Of The Corn–Water–Ethanol–Beef Nexus, Heydi Han

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This dissertation examines the transition from conventional linear agricultural and food bioenergy systems toward more circular, resilient, and resource-efficient configurations. Prior research indicates that spatial and temporal variability in soil, weather, animal biological responses, and management decisions strongly influences productivity, nutrient-use efficiency, and profitability. Studies have also shown that a diversified circular system can buffer these sources of variability, improving stability and adaptive capacity. Building on these insights, the central focus of this work is to develop an integrated modeling framework to evaluate circularity within the Corn-Water-Ethanol-Beef (CWEB) nexus and explore how climate variability and management choices shape system-wide performance. …


Investigating Molecular Rotation And Vibration With Ultrafast Electron Diffraction, Haoran Zhao Dec 2025

Investigating Molecular Rotation And Vibration With Ultrafast Electron Diffraction, Haoran Zhao

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Ultrafast electron diffraction (UED) has emerged since the late 20th century as a powerful technique for resolving molecular dynamics. With its high spatial and temporal resolution, UED can now measure rotational motion induced by linearly polarized, nonresonant, nonadiabatic laser pulses—one of the fundamental molecular degrees of freedom with broad applications. By combining laser-induced alignment with UED, new capabilities such as three-dimensional structural retrieval and isotope detection have been demonstrated, as discussed in Chapter 2.

In Chapter 3, three symmetry relations in the coefficients of rotational wave packets are identified and derived, reducing the computational cost of simulating asymmetric-top molecular alignment …


Electrical And Magnetic Properties Of Ferroic Oxide Thin Films And Free-Standing Membranes, Qiuchen Wu Dec 2025

Electrical And Magnetic Properties Of Ferroic Oxide Thin Films And Free-Standing Membranes, Qiuchen Wu

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This dissertation presents a comprehensive study of the electrical, magnetic, and transport properties of epitaxial ferroic oxide thin films and free-standing membranes, including ferroelectric PbZr0.2Ti0.8O3 (PZT) and ferrimagnetic NiCo2O4 (NCO).

We evaluate the effects of electrostatic and mechanical boundary conditions on the ferroelectric properties of free-standing PZT membranes by transferring them on three types of base layers: the metallic Au, strongly correlated oxide La0.67Sr0.33MnO3 (LSMO), and 2D semiconductor MoS2. The coercive field and domain wall roughness depend sensitively on the metallicity and surface roughness of …


Ai-Enabled Robotic Nitrogen Management, Ankita Kalra Dec 2025

Ai-Enabled Robotic Nitrogen Management, Ankita Kalra

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Nitrogen management in corn agriculture faces economic and environmental challenges, motivating development of precision, site-specific solutions. This dissertation presents AIR-N (AI-Enabled Robotic Nitrogen Management), a novel system that integrates cloud-based artificial intelligence with an autonomous field robot (Flex-Ro) to optimize nitrogen fertilizer application in real time. The research is driven by the need to improve nitrogen use efficiency while reducing leaching and emissions.

Comprehensive architecture (Cloud-E) was designed using Amazon Web Services to ingest multi-modal agronomic data (soil sensors, crop reflectance, weather) and host machine learning models. A Random Forest-based model was trained on historical field data to predict spatially …