Digital Commons Network^™

Sparse Neural Network To Enhance Performance Under Limited Parameter Constraints., Nailah Rawnaq

Graduate Theses and Dissertations

Over the past decade, the widespread adoption of deep neural networks has been a breakthrough driven by significant computational advancements. Additionally, the number of parameters of those models is exponentially increasing for performing complex tasks and achieving better performance. However, in most practical cases, often there are constraints in the number of parameters due to limited resources in storage size and computational cost. Network pruning can lead to an optimal solution to this problem. In this thesis, I present supporting evidence to the hypothesis that higher sparsity leads to better performance for a convolution-based neural network. I perform performance studies …

Hierarchical Spatial Abundance Models For Migratory Shorebirds, Md Shahbaz Alam

Graduate Theses and Dissertations

Predicting the distribution and abundance of migratory shorebirds is crucial for effective conservation planning. This research applies hierarchical spatial models to predict counts and spatial variations of three shorebird species: Semipalmated sandpiper (sesa), Ruddy turnstone (rutu), and Whimbrel (whim). Different versions of the Poisson, Negative Binomial, and Hurdle regression models are employed to tackle specific data characteristics, such as overdispersion and excess zeros. Model comparisons are performed in terms of likelihood measures and cross-validation. The Hurdle model for sesa and rutu and the Negative Binomial model for whim effectively captured spatial patterns, highlighting potential hotspots. Mean predictive count further emphasized …

The Effects Of Grading Equity Practices On Students: Do Student Perceptions Of And Teachers’ Exposure To Grading Equity Practices Matter?, Sarah Ruth Morris

Graduate Theses and Dissertations

This dissertation critically examines grading practices within schools, tracing the evolution from traditional to modern approaches and highlighting the social dimensions and debates surrounding grading. Through a mixed-methods study spanning three empirical chapters, it explores students' and teachers' perceptions of grading practices, the impact of professional development (PD) on teachers' approaches to grading equity, and the resultant effects on student outcomes. Chapter Two reveals students' preferences for practices that recognize effort and support academic growth, alongside a tension between Pre-AP students' resistance and the support from students under high stress. Chapter Three finds that while PD can shift teachers' views …

Gan With Skip Patch Discriminator For Biological Electron Microscopy Image Generation, Nishith Ranjon Roy

Graduate Theses and Dissertations

GAN models have been successfully used for image generation in various sections such as real-life objects like human faces, cars, animal faces, landscapes, etc. This work focuses on biological electron microscopy (EM) image generation. Unlike other real-life objects, biological EM images are obtained through electron microscopy techniques to study biological specimens. Electron microscopy offers high resolution and magnification capabilities, making it a powerful tool for visualizing biological structures at the nanoscale. However, using GAN models for biological EM image generation poses challenges due to the complex and unique arrangements of biological structures and the sparse and asymmetrical patterns in EM …

Feasibility Assessment And Container Traffic Forecasting Of Inland Waterway Container On Barge Transportation, Fan Bu

Graduate Theses and Dissertations

Container on Barge (COB) transportation is an intermodal freight transport mode that moves shipping containers via barges on navigable inland and intracoastal waterways. During the past twenty years, COB has been a growing mode of container shipping globally due to its low-cost, eco-friendly, and congestion-reducing characteristics. Europe and China are currently leading global COB transportation, and the United States (U.S.) may have the potential to achieve economic benefits through the implementation of COB within its intermodal transportation system. To explore this potential, this dissertation investigates the implementation feasibility of COB transportation within the U.S. intermodal freight transportation system. Three contributions …

A Grounded Theory Study Of White Educators' Conceptualizations And Negotiations Of Culturally Centered Practices In Colleges Of Agriculture And Related Sciences, Isabel M. Whitehead-Adams

Graduate Theses and Dissertations

The racial and ethnic demographics of higher education are becoming increasingly diverse; however, faculty demographics remain predominantly White. With agriculture being one of the largest economic sectors, often with many roles to fill, recruiting and retaining racially and ethnically diverse students into agricultural and related science post-secondary programs, hereby referred to as agricultural programs, is crucial to drawing talent into the agricultural workforce. However, racial and ethnic demographics among students in post-secondary agricultural programs also remain predominantly White. Established pedagogical approaches for supporting culturally diverse have been established, such as Culturally Responsive Teaching. There is little to no research exploring …

Quantifying Physical Function: Moving Towards A New Definition And Better Assessment, Anthony Campitelli

Graduate Theses and Dissertations

Though poor physical function (PF) and disability are two of the most impactful problems facing older adults today, the field of kinesiology has not yet devised a method of measuring PF, thus limiting investigations with the potential to lead to improved PF interventions and assessments. This dissertation aimed to develop a single, continuous measure of PF using a latent variable modeling approach, and then use the generated scores to evaluate the role of lower body muscular power in PF assessment and to construct an improved PF assessment battery for predicting overall PF. Each aim of this dissertation was addressed through …

Student Perceptions And Academic Performance When Taught With Multiple Active Learning Methods In A High Enrollment Undergraduate Human Physiology Course, Kate Ireton Walker

Graduate Theses and Dissertations

When instructing very large groups of students in science, it can be difficult to engage all students in the content and measure their understanding. A major unaddressed challenge in science instruction is how specifically to design and implement strategies that engender active learning particularly in high-enrollment undergraduate courses. Active learning, which represents a diverse set of strategies, may include student engagement as part of instruction through discussions, active movement, and application (Bernstein, 2018; Cavanagh, et al. 2016; Michael, 2006 & Wilke, 2003). This study was designed to provide data addressing the gap in the literature regarding how the continual implementation …

Understanding And Control Of Frustration And Topological Defects In Ferroic Matter, Suyash Rijal

Graduate Theses and Dissertations

Ferroic matter are of great importance as they provide a platform to extend the understanding of many-body physics and also for their amazing functional properties relevant for technological advancements. The work in this dissertation is dedicated to two of such ferroic materials.

First is CrGeTe₃ (CGT), a two dimensional (2D) magnet discovered in 2017. The discovery of two-dimensional magnetism has invigorated the research community as their low dimensionality offers a unique avenue to understand and investigate the origin of magnetism in these atomically thin systems and harvest diverse application such as information processing, storage and transfer using their magnetic …

Exploring Telehealth Utilization Through Data Analytics, Statistical Analyses, And Machine Learning Techniques, Aysenur Betul Cengil

Graduate Theses and Dissertations

This dissertation investigates the utilization of telehealth services, initially focusing on the Arkansas healthcare system and then extending the analysis nationwide. It aims to understand the factors influencing telehealth adoption and its impact on healthcare delivery. After examining telehealth utilization in Arkansas from 2018 to 2022, the research utilizes a comprehensive dataset from Epic Cosmos, which includes a wide range of patient and visit data from multiple healthcare facilities across the United States from 2018 to 2023. This timeframe allows for a detailed analysis of telehealth trends before, during, and after the COVID-19 pandemic. In Chapter 2, we analyze key …

Quantum Modeling & Experimental Studies Of Radical Chemistry, Justin Michael Barrett

Graduate Theses and Dissertations

This work describes two projects centered around radical chemical mechanisms. The first investigation generalized the utility of a C-N bond homolysis followed by a [1,3] – rearrangement synthetic strategy found possible in N-alkylated thiazole & benzothiazole species onto analogous systems. Computational investigation guided the inquiry on structurally analogous systems that would favor a radical, [1,3] – rearrangement. Herein, we describe the implementation of that mechanism to transform Breslow Intermediate-like substrates into tertiary alcohol and amide products under facile conditions. We confer on the proficiency of this strategy with 2-pyridinemethanol and the problematic implementation with 2-(aminomethyl)pyridine. The second investigation solved a …

Computational Models That Exploit Spatial, Temporal, And Voltage-Current Relationships In The Electrochemical Generation-Collection Of Redox-Active Molecules, Miguel Angel Abrego Tello

Graduate Theses and Dissertations

The numerical studies in this dissertation explore the application of redox cycling, an advanced electrochemical technique, for analyzing bioelectrochemical systems with a particular focus on small-volume samples and involves electrodes that can be activated to oxidize and reduce, separated by varying distances and featuring different geometries. The redox cycling approach facilitates the spatio-temporal interrogation of kinetics, mass transport, and the quantification and identification of chemical systems. We optimize a previously fabricated neural probe design on an SU-8 substrate, featuring coplanar arrays of nine microband electrodes suited for in vivo applications. Through comprehensive in situ and in silico redox cycling studies …

Impacts Of High-Frequency Operation On Magnetics And Performance On Isolated Power Electronic Converter Design, David Arturo Porras Fernandez

Graduate Theses and Dissertations

The pursuit of high-power density and high switching frequency is a central theme in the advancement of power electronic converters. While these parameters offer significant benefits in terms of compactness and performance, they also introduce challenges related to efficiency and thermal management. This doctoral dissertation aims to provides a design framework to analyze the implications of high-frequency operation (> 100 kHz) on magnetics design and performance in power electronic converters, particularly when integrating silicon carbide (SiC) power modules. It examines the advantages and disadvantages of high-frequency operation and delves into its effects on the performance of the converter, focusing on …

Proton-Coupled Electron Transfer To Drive Biomass Conversion, Cody Canote

Graduate Theses and Dissertations

Meeting rising demands for commodity chemicals while simultaneously easing reliance on fossil fuels presents one of the most substantial challenges for chemistry to date. Biomass has emerged as a sustainable precursor to commodity chemicals but requires substantial deoxygenation to displace petrochemicals. Development of efficient catalysts to achieve these transformations remains one of the central goals of inorganic and organometallic chemistry. Electrochemical strategies to propel biomass conversion are attractive, providing the driving force for reactivity and insights into catalyst mechanism. This work focuses on proton-coupled electron transfer (PCET) to facilitate redox catalysis in biomass up conversion and homolytic bond cleavage in …

Modeling, Optimization, And Characterization For Choke Horn Antennas, Ibrahim Nasser I Alquaydheb

Graduate Theses and Dissertations

This dissertation presents a comprehensive study focusing on the modeling, optimization, and characterization of choke horn antennas (CHAs). An analytical model designed to capture the parameters of CHA and derive the total radiated fields from the choke and waveguide elements is primarily focused on in this work. Compared to the use of simulation software, such as ANSYS HFSS (High Frequency Structure Simulator) or CST Studio, which employs numerical methods to simulate and calculate antenna performance, numerous advantages are offered by the analytical model. Analytical models provide deeper insight into electromagnetic interactions and the principles governing antenna behavior, leading to a …

Investigating The Applications Of Peps To The Measurement Of The Stabilities Of Staphylococcal Nuclease (Stw) And Human Acidic Fibroblast Growth Factor (Hfgf1), Motolani Omolade Matthew

Graduate Theses and Dissertations

This dissertation presents a detailed investigation into the applications of Protein Equilibrium Population Snapshot H/D Exchange Electrospray Ionization Mass Spectrometry (PEPS-H/D exchange or PEPS) method. This method is based on protein equilibrium unfolding, and its fundamental capability is to capture a "snapshot" of the protein's state, allowing us to monitor the ratio of the unfolded to folded populations at different chemical denaturant concentrations. First, to increase the accuracy of PEPS data analysis for assessing protein stability, the traditional linear extrapolation method (LEM) was replaced. Instead of using LEM, which calculates free energy change based on the peak ratio of unfolded …

Effects Of Measurement Error In Student Pre-Post Test Score On The Recovery Of The Estimates Of Teachers Value-Added Scores, Merlin J. Kamgue

Graduate Theses and Dissertations

Abstract Background: Value-added models (VAMs) are statistical tools used to gauge a teacher’s impact on student performance by analyzing standardized test scores. These models project students’ future performance based on past scores and compare the projection to actual outcomes, accounting for differences in student backgrounds. However, the standard error of measurement (SEM) inherent in all measurement tools is often overlooked in VAMs. Aims and Objectives: This study aims to investigate the impact of test reliability on teacher and school score estimates within a Bayesian framework. We will precisely manipulate the reliability of standardized tests by adjusting the standard error of …

Advancing Prediction And Decision Analytics Techniques To Improve Treatment Of Tuberculosis, Maryam Kheirandish Borujeni

Graduate Theses and Dissertations

Tuberculosis (TB) remains a global health challenge, significantly impacting morbidity and mortality rates worldwide. Despite advancements in diagnosis and treatment, TB continues to pose substantial challenges, particularly in low-resource settings. This dissertation aims to develop a robust treatment monitoring framework for TB patients to ensure personalized and effective treatment using demographic and clinical information. The current standard TB treatment framework, recommended by the World Health Organization (WHO), involves monitoring patients through laboratory tests such as smear and culture sputum tests at specific time points during treatment. These tests, however, are not fast and accurate enough to determine the severity of …

Leveraging Machine Learning And Stochastic Programming To Address Vaccine Hesitancy In Public Health Resource Allocation, Hieu Trung Bui

Graduate Theses and Dissertations

Infectious disease outbreaks highlight the urgent need for effective strategies to distribute vaccines and allocate critical healthcare resources to contain the disease and reduce its negative impacts on the population. Managing these allocations is a significant challenge, especially in marginalized communities facing uncertainty in healthcare demand and logistical constraints. This dissertation addresses these challenges by investigating factors that influence dynamic changes in vaccine hesitancy (VH) and its implications for disease spread and healthcare resource demand. It develops optimization models for vaccine distribution and resource allocation under uncertainty, validated with data from the COVID-19 pandemic in the U.S. The first study …

Evaluating Margin Protection (Mp) Crop Insurance As A Risk Management Tool For Rice Producers In Arkansas, Kaleem Azmat Chattha

Graduate Theses and Dissertations

Agricultural producers bear many risks, including production risks stemming from uncertainty in weather and pest pressure and price risks arising from market volatility. Federal Crop Insurance has become one of the most popular tools to manage these risks. While yield and revenue crop insurance tend to be the most popular production and price risk management tools provided by the government, participation in Margin Protection insurance lags far behind despite providing production, crop price, and input price risk protection. This study aims to uncover whether Margin Protection crop insurance is an effective risk management tool by estimating the optimal coverage level …

On Laudenbach-Type Exact Sequences, Jorge Andres Robinson Arrieta

Graduate Theses and Dissertations

Laudenbach proved that the mapping class group of the connected sum of $n$ copies of $S^2 \times S^1$ is an extension of $\text{Out}(F_n)$ by a finite group. Brendle, Broaddus and Putman proved that this exact sequence splits. We provide an explicit section $s$ of this split exact sequence. Given a locally finite graph $\Gamma$, Udall proved that the mapping class group of the doubled handlebody associated to $\Gamma$ is an extension of $\map(\Gamma)$ by a possibly infinite direct product of $\Z_2$, and proved that this exact sequence splits. We provide an explicit formula for this section $s$ of $\Psi$ restricted …

Green At Eye Level: From Measurement Approaches To Simulated Models And Inequality Assessments In U.S. Major Cities, Jingjing Yan

Graduate Theses and Dissertations

This dissertation delves into the multifaceted dynamics of urban greenness, addressing critical aspects of sustainable urban development. Providing urban green spaces has been widely acknowledged to offer numerous benefits to individuals and communities. Recently, there has been a growing recognition of the importance of evaluating urban greenness from a human-centered perspective, partly due to the rapid development of eye-level greenness measurement. First, to provide a comprehensive overview of measurement approaches and topics related to eye-level urban greenness, a systematic review of 77 papers was conducted in this research. This review revealed that street view images are the primarily utilized data …

Passages, Arden Carlson

Graduate Theses and Dissertations

Passages is a collection of wood sculptures and drawings by Arden Carlson, exploring a mesh of southern intimacies and queer musings; underpinned by the logics of belief, grief, and love. The result is a tender field of angelic birds fixed in flight over gnawed surfaces of grain and graphite. The following dissertation details the artist’s logic during the construction of the visual art thesis exhibition, Passages. The writing is composed in an autoethnographic format, backed by supporting anecdotes and creative methodologies that help to route the operational modes used. Near the end of this writing, you’ll find an additional addendum …

Addressing Data Limitations Of Commercial Waterways Via Machine Learning And Stochastic Optimization, Sanjeev Bhurtyal

Graduate Theses and Dissertations

Freight transportation is a crucial component of the US economy, with truck, rail, and water contributing significantly to the Gross Domestic Product (GDP). However, challenges arise in maintaining infrastructure capacity to accommodate the growing tonnage and value of freight transportation. Waterways offer high efficiency and environmental friendliness, with the capacity to transport substantial cargo volumes. Utilizing waterways can alleviate bottlenecks in landside transportation, accommodating the rising tonnage of commodity flow in the US. Despite the advantages of waterway transportation, the data limitations hinder informed decision-making regarding port operation and infrastructure investment. The lack of granularity and timeliness in available data …

The Ai Effect: Rethinking Design Workflows For Enhanced Productivity And Creativity, Israel Adeleye

Graduate Theses and Dissertations

Advancements in artificial intelligence and machine learning are transforming how designers work with computers. This thesis explores the developing relationship between artificial intelligence (AI) and design processes, focusing on how it impacts the creation of digital experiences. This study examines the impact of AI on design, highlighting how AI can improve efficiency and creativity alongside ethical challenges and the need to preserve human uniqueness in digital creations. It investigates AI's effects on design workflows, creativity, and the designer's evolving role through interviews, content analysis, case studies, and surveys. The aim is to understand AI's influence on designer productivity, innovation, and …

Characterizing The Role Of Chemo-Mechanical Couplings In The Activation Process Of Proteins That Undergo Conformational Changes, Ugochi Isu

Graduate Theses and Dissertations

Proteins are not static entities; rather, they are dynamic macromolecules that undergo conformational changes to perform their biological functions. These structural transitions are often coupled to chemical events such as lipid interactions, or changes in the cellular environment. Understanding the intricate interplay between chemical perturbations and the resulting mechanical response is crucial for elucidating the activation mechanisms of proteins. This dissertation aims to characterize the role of chemo-mechanical couplings in the activation process of two G protein-coupled receptors (GPCRs): Cannabinoid Receptor 1 (CB1) and Metabotropic Glutamate Receptor 1 (mGluR1). We employ molecular dynamics simulations to investigate the conformational landscapes of …

Analysis And Construction Of Artificial Neural Networks For The Heat Equations, And Their Associated Parameters, Depths, And Accuracies., Shakil Ahmed Rafi

Graduate Theses and Dissertations

This dissertation seeks to explore a certain calculus for artificial neural networks. Specifically we will be looking at versions of the heat equation, and exploring strategies on how to approximate them.

Our strategy towards the beginning will be to take a technique called Multi-Level Picard (MLP), and present a simplified version of it showing that it converges to a solution of the equation (^∂/_∂t u_d ) (t, x) = (∇² _x u_d)(t, x).

We will then take a small detour exploring the viscosity super-solution properties of solutions to such …

Investigations Into The Expansion Of Breslow-Type Intermediate Reactivity Via Radical C-N Bond Homolysis, Jacklyn J. Kubik

Graduate Theses and Dissertations

The Breslow intermediate is a key intermediate in catalytic transformations like the benzoin condensation and Stetter reaction. These intermediates were first postulated by Ronald Breslow in 1958. Since then, a number of researchers have sought to prove their existence and expand upon the reactions possible using these intermediates. In the sixty plus years since this intermediate was first postulated the reaction scope has expanded significantly, Breslow and breslow-type intermediates have expanded to encompass benzothiazoles, imidazoles, benzoimidazoles, triazoles, thiadiazoles, diamino type structures, and most recently pyridine structures. The expansion of these reactions has opened up new avenues of exploration and previously …

Geochemical Analysis Of Basement Rock As A Potential Metal Source In Mississippi Valley-Type Ores, Southern Midcontinent U.S.A., Mackenzie Moorhead

Graduate Theses and Dissertations

Mississippi Valley-Type (MVT) ores are epigenetic, sedimentary hydrothermal base metal deposits that exist worldwide with type localities in the midcontinent United States. These Permian-aged sulfide ores represent an extraordinary concentration of economic metals, Pb and Zn. Ore deposits occur in vast districts that have a rich mining history. The Pb and Zn from these deposits account for 24% of worldwide reserves. The geologic processes responsible for MVT ore genesis are not fully understood, especially the sourcing of ore constituents. In the midcontinent, the Ouachita Orogeny expelled saline hydrothermal brines in response to high rates of subsidence. These fluids migrated through …

Towards Side-Channel Infrastructure For Software Implementations Of Pqc Algorithms, Tristen Teague

Graduate Theses and Dissertations

Post-Quantum Cryptography (PQC) is a new class of asymmetric cryptography algorithms that are supposed to be secure against both classical computers and quantum computers through Shor’s algorithm. Since PQC algorithms are currently being standardized, they will replace older standardized asymmetric algorithms (such as RSA) and will be deployed within the digital infrastructure. Before implementations of the PQC algorithms are placed into the infrastructure, they must undergo evaluation of both performance and security. One such security issue that needs large investigation before deployment are side-channels. Side-channel attacks (SCA) are a method of gathering information from the implementation, such as power-consumption and …