Digital Commons Network^™

Comparative Mechanical Property Evaluation Of Ultra-High-Performance Concrete Reinforced With High-Strength Steel Straight And Hooked Fibers, Sujan Kumar Singh

Civil Engineering Theses - Archive

This study investigates the tensile properties and ductility of ultra-high-performance concrete (UHPC) reinforced with high-strength steel hooked fibers with a tensile strength of 445 ksi (3,070 MPa) and compares its tensile performance to that of UHPC reinforced with commonly used high-strength smooth steel microfibers with a tensile strength of 2,160 MPa (313 ksi). The research is based on a proprietary mix developed at the University of Texas at Arlington and investigates the mechanical properties of UHPC with varying fiber volume fractions of 1.5%, 2%, 2.25%, and 2.4%. The experimental results indicate that UHPC reinforced with high strength hooked fibers generally …

Top Management Team Functional Diversity And Firm Performance: A Mediation Analysis, Tsung Hsuan Yang

Accounting Dissertations - Archive

In my dissertation, I study whether the top management team (TMT) between-member and within-member functional diversities affect firm performance. Between-member functional diversity, known as Dominant Functional Diversity (DFD), refers to the heterogeneity of functional experts on a TMT, and within-member functional diversity, known as Intrapersonal Functional Diversity (IFD), refers to the aggregate functional breadth of TMT members. My analysis indicates that IFD is positively and significantly associated with firm performance. The relationship between DFD and firm performance is also positive but not statistically significant. In the second analysis, I perform a mediation analysis to explore plausible mechanisms through which TMT …

A Machine Learning Approach To Constructing Ramsey Graphs Leads To The Trahtenbrot-Zykov Problem., Emily Hawboldt

Electronic Theses and Dissertations

Attempts at approaching the well-known and difficult problem of constructing Ramsey graphs via machine learning lead to another difficult problem posed by Zykov in 1963 (now commonly referred to as the Trahtenbrot-Zykov problem): For which graphs F does there exist some graph G such that the neighborhood of every vertex in G induces a subgraph isomorphic to F? Chapter 1 provides a brief introduction to graph theory. Chapter 2 introduces Ramsey theory for graphs. Chapter 3 details a reinforcement learning implementation for Ramsey graph construction. The implementation is based on board game software, specifically the AlphaZero program and its …

Evaluating Chatgpt For Recommendation: How Does The Ability To Converse Impact Recommendation?, Kyle Spurlock

Electronic Theses and Dissertations

Recommendation algorithms have become an absolute necessity in the modern world to avoid information overload. However, the interaction between the human and the system is largely superficial and without any real contact. If you are given poor recommendations, you have no choice but to sift through mountains of content on your own until the model learns to accommodate your tastes more. This is bad for business as well as the consumer. Recently, large language models like ChatGPT have seen a significant rise in popularity due to their ease of use and wide range of knowledge. It has now become nearly …

Development And Application Of A Microfluidic Platform For Quantifying Intra-Tumoral Compressive Stress., Zachary P. Fowler

Electronic Theses and Dissertations

Cancer progression is linked to the emergence of aberrant mechanical signaling in the tumor microenvironment. Modulation of extrinsic signals, such as ECM stiffness and composition, have been thoroughly explored. However, the development of solid stresses within the tumor remains poorly understood. To address this, we have developed a microfluidic platform that generates deformable alginate microbeads that allow for the quantification of compressive stresses generated within a growing glioblastoma (GBM) tumorsphere. PDMS microfluidic devices were fabricated via SU-8 mold with channels ranging from 10µm-40µm in diameter. Fluorescently labeled sodium alginate underwent a cross-linking reaction within the device to generate monodisperse beads …

Investigation Of Possible Inflammatory Response After Ultrasound And Microbubble Procedure In The Spinal Cord., Jenna Wilkerson

Electronic Theses and Dissertations

The purpose of this experiment is to explore the inflammatory effects of focused ultrasound paired with intravenously delivered microbubbles when used in the lumbar spinal cord. There are currently very few pharmaceuticals that can successfully enter the blood spinal cord barrier (BSCB). This technique used at the lumbar enlargement might allow targeted treatment of pathologies involving the spinal cord.

To test the possible inflammatory response of this technique, an animal experiment was performed. 15 animals were given a T12 laminectomy and allowed to fully recover. Once recovered, all animals received FUS+MB at L2 and were euthanized in groups of five …

Addition Of Process Control Experiment To Unit Operations Ii Laboratory., Bradley Esselman

Electronic Theses and Dissertations

Process control is an essential aspect of manufacturing, contributing to improved process safety, efficiency, product consistency, and energy optimization. Chemical engineers are often responsible for ensuring the safe, efficient, and cost-effective operation of industrial processes, and process control plays a pivotal role in accomplishing this.

Chemical engineering students at the University of Louisville complete the course, Elements of Process Control, during the second semester of their fourth year. This lecture-based course offers limited hands-on, practical experience. To supplement the lack of hands-on experience in the classroom, a new process control experiment was designed and implemented into the Unit Operations …

Influence Of Hydrologic History On Nitrogen Cycling In Lake Sediments, Emily Jainarain

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Water quality is declining in freshwater lakes around the world due to environmental change and anthropogenic activities that threaten the physical, ecological, and geochemical integrity of freshwater ecosystems. Excess N and P in lakes can cause eutrophication, a major driver of water quality impairment that leads to excessive algal growth, or harmful algal blooms (HABs), and poses risks to recreation, fisheries, and public drinking water. Water level fluctuations in lakes are expected to become more frequent and intense as climate change increases periods of drought and alters precipitation patterns, and fluctuations may stimulate biogeochemical reactions in littoral sediments that add …

Using Computational Fluid Dynamics For Predicting Hydraulic Performance Of Arced Labyrinth Weirs, Shelby J. Koldewyn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Our world is dynamic and as hydrologic research continues, the magnitude of flood estimates used in hydraulic design for reservoirs has increased. Consequently, many existing spillways are now undersized and unable to meet discharge requirements. These spillways often have a fixed footprint, so nonlinear weirs (e.g., labyrinth weirs) are often a viable solution. For reservoir applications, arcing labyrinth weirs in plan view increases hydraulic efficiency because of better cycle orientation to the approaching flow from the reservoir. This study supplements available physical arced labyrinth weir hydraulic data by observing flow characteristics of two numerical models (α=16°; θ=10° …

Public Space And Well-Being: An Empirical Study Of Central Park In Old Louisville., Maryam Entezam

Electronic Theses and Dissertations

Urban green spaces have been receiving attention in urban planning and the health profession in the 21^st century as environmental elements that contribute to well-being. This dissertation explored the relationship between green space usage and individuals’ physical, mental, and social well-being. This empirical research focused on Central Park in Old Louisville to examine how residents use the park and whether it contributes to the well-being of residents. After exploring the existing literature, I identified four well-being indices: (1) perceived health (PHI), (2) health outcome (HOI), (3) mental well-being (MWI), and (4) social well-being (SWI). Frequent Park usage is expected …

Applications Of Probability Of Success In The Well Delivery Process To Improve Risk, Opportunity, And Cost Assurance, Romar Alexandra Gonzalez Luis

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Oil and Gas (O&G) well drilling is risky and expensive. The cost of drilling is typically underestimated, and there is little understanding of the certainty or Probability of Success (POS) of achieving the well objectives within the estimated cost. This dissertation presents, for the first time, a publicly available POS Cost method/tool that enables O&G operators to estimate the cost of well drilling substantially more accurately and improve the POS of accomplishing the drilling for the estimated cost. This POS Cost method employs a comprehensive, expert-based assessment of risks and risk mitigations that are incorporated into a Monte-Carlo-based simulation of …

Glass Bubbles Grafted With Polymer Brushes For Liquid Hydrocarbon Fire Extinguishment, Randall Snipes

All Dissertations

The current most efficient solution to fighting liquid pool fires involves the use of firefighting foams containing fluorinated surfactants. The physiochemical properties of these foams are considerably different to all other currently available firefighting foams. Fluorinated surfactants lower the surface tension to a point where the foam solution draining from the foam structure forms a continuous aqueous film on the surface of a volatile hydrocarbon fuel, adding an additional barrier to fuel vapor diffusion to the burning fire. For this reason, these foams qualify as aqueous film forming foams (AFFFs). However, fluorinated compounds are extremely harmful for the environment due …

Microstructural Characterization Of High-Protein Dairy Powders, Prafulla Salunke, Athira Syamala, Lloyd Metzger

Dairy Science and Food Science Faculty Publications: 2022 to Present

Dairy proteins are potential and multipurpose ingredients used to prepare various food products. It exhibits many beneficial functionalities and bioactivities in the processing of food products. All the functionalities of different dairy proteins depend on their peculiar structural characteristics. So, the present study aimed to characterize high-protein powders with different matrices (milk protein concentrate (MPC), rennet casein (RCN), micellar casein concentrate (MCC), whey protein isolate (WPI), and native whey concentrate (NWC)) for their composition, handling, and reconstitution properties, and microstructure and compared them with whole milk powder (WMP) and skim milk powder (SMP). The bulk density of the high-protein powders …

Cobalt Nanowire Catalyst For Fischer-Tropsch Reaction, Jordan Gates

Master's Theses

The Fischer Tropsch reaction is a long-standing chemical reaction that enables the generation of hydrocarbons from hydrogen and carbon monoxide. Funding for research in this field has varied over the years due to the economics of producing synthetic fuel versus processing crude oil. The development of new reactors and catalysts has increased the viability of this process, but it still isn’t enough. Presented in this thesis is a novel nanowire catalyst that is not structured in the same manner as conventional catalysts. In this work it is our goal to compare the nanowire catalyst with a traditional catalyst on the …

Reentry Services In Non-Urban Counties In Texas: A Directed Content Analysis Of Reentry Provider Websites, Monica Canizares

Social Work Theses - Archive

Health, social, and justice outcomes for returning residents after incarceration are concerning, with implications for service providers, especially in non-urban areas. Texas has made efforts to reduce its incarcerated population, but more attention is necessary to improve outcomes for returning residents. The state is only able to offer services to a small number of returning residents, and non-profit organizations are filling the gap of reentry service provision. This study aimed to understand what services are being offered by non-governmental reentry providers in non-urban areas of Texas through a mixed-methods, directed content analysis of reentry providers' websites. The results summarize features …

Preliminary Evaluation For Lean Implementation In A Small Manufacturing Company, Ronald Lynch

Masters Theses & Specialist Projects

Lean management and tools have many positive effects on a company including increased profitability, and efficiency. Lean tools can be implemented in any type of company with a proper evaluation through the creation of Value Stream Map. This paper will demonstrate how a Value Stream Map (VSM) will provide an easier transition to a lean environment. A local company of about 100 employees will be analyzed to create a current and a future VSM. The areas of opportunity for improvement in a lean environment includes recommended lean implementations and the future VSM. Functions of the company that will be analyzed …

Understanding The Role Of Interactivity And Explanation In Adaptive Experiences, Lijie Guo

All Dissertations

Adaptive experiences have been an active area of research in the past few decades, accompanied by advances in technology such as machine learning and artificial intelligence. Whether the currently ongoing research on adaptive experiences has focused on personalization algorithms, explainability, user engagement, or privacy and security, there is growing interest and resources in developing and improving these research focuses. Even though the research on adaptive experiences has been dynamic and rapidly evolving, achieving a high level of user engagement in adaptive experiences remains a challenge. %????? This dissertation aims to uncover ways to engage users in adaptive experiences by incorporating …

Hybridly Integrated Semiconductor Lasers And Amplifiers On Iii-V/Si3n4 Platform For Beam Combining And Other Advanced Applications, Siwei Zeng

All Dissertations

Photonic integrated circuits (PICs) are devices that integrate multiple photonic functions on a small chip and allow for accurate dimension control and massive production. Similar to electronic integrated circuits, PICs can significantly reduce the system cost, size, weight, and operation power (CSWaP). Recently, the PIC technology has transformed many optical technologies which traditionally rely on tabletop systems and bulky components, such as optical interconnects, nonlinear optics, and quantum photonics, into a chip-scale platform. This device and system miniaturization has successfully led to a wide range of practical applications in computing, sensing, spectroscopy, and communication. However, the traditional passive PIC platform …

"A Show That Proves The Worst Monsters Are Real": Media And Social Media Impact On Criminal Trials And Post-Conviction Guilt As Perceived By Criminal Justice Students., Jennifer Leigh Patterson

Criminology & Criminal Justice Theses - Archive

This study, using survey data collected in 2022, investigates how consuming true crime media, from media such as podcasts, influences fear and anxiety among criminal justice students. In addition, the relationship between viewing criminal trials in real time and forming opinions different from the sentencing juries is assessed. Results suggest that there is no significant relationship between the consumption of true crime media and fear or anxiety. Moreover, viewing criminal trials in real time does not have a signficant effect on the formation of opinons that differ from criminal juries. Limitations, implications, and directions for future research are discussed.

Increasing The Safety Of Bicyclists Using A Cyclist Behavior Questionnaire And A Smartphone Based Application, Anika Jannat Rimu

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

ABSTRACT: Bicycling is beneficial for health, the environment, road users’ flexibility, and personal expenses. Compared to motor vehicles, they are an active mode of transport, cause minimum pollution, are affordable, and can easily navigate through the increasing traffic all over the world. This increase in traffic, however, also increases the possibility of crashes with motor vehicles. Bicyclists, being more exposed to traffic than drivers, suffer fatal consequences from a crash. Therefore, a standard tool is required to understand bicyclist behavior on the road. This tool can provide insights into bicyclists’ behavior so that appropriate infrastructure or policy changes can be …

Identification Of Acidic Residues In Proteins By Selective Chemical Labeling And Tandem Mass Spectrometry, Fnu Ashima

Chemistry & Biochemistry Theses - Archive

Proteins play important role in carrying out a wide range of cellular activities. They are subjected to various post-translational modifications (PTMs) by the addition of functional groups such as acetyl, phosphoryl, and methyl which leads to changes in their biological functions, localization, activity, and structure. The growth of MS technology has immensely facilitated the identification of PTMs comprehensively. This dissertation focuses on mapping these changes using covalent labeling techniques by tagging carboxylic acid residues, which undergo various kinds of PTMs. The second chapter focuses on the methods designed for Affinity Purification Mass Spectrometry (AP-MS) chemical cross-linking (CXL) of protein complexes. …

Determining How Anthropogenic Change Filters Biological Communities And How Species Modify Their Traits In Response To Urbanization, Kristopher Warren Row

Biology Dissertations - Archive

Humans are significantly altering the environment at an alarming pace, leading to a reduction in species diversity. This transformation has created modified habitats where some species struggle to survive, while a few others not only manage to survive but thrive. One of the most drastic forms of habitat modification is urbanization, which is spreading worldwide and contributing to the decline of biodiversity. Urbanization has given rise to urban-tolerant species that differ ecologically from species that avoid urban areas across various niche dimensions. These urban-tolerant species must adapt to changes in food sources, microhabitat conditions, and alterations in physical habitat structures. …

Computational Comparison Of Medializing Tibial Tubercle Osteotomy And Trochleoplasty In Patients With Trochlear Dysplasia, Clare K. Fitzpatrick, Robert N. Steensen, Oliver Alvarez, Amy E. Holcomb, Paul J. Rullkoetter

Mechanical and Biomedical Engineering Faculty Publications and Presentations

Medial patellofemoral ligament reconstruction (MPFLR) has emerged as the procedure of choice for recurrent patellar dislocation. This addresses soft tissue injury but does not address underlying anatomic factors, including trochlear dysplasia, that are commonly present and increase risk of dislocation. Quantification of the stability offered by other surgical interventions, namely, medializing tibial tubercle osteotomy (mTTO) and trochleoplasty, with and without MPFLR, may provide insight for surgical choices in patients with trochlear dysplasia. We developed subject-specific finite element models based on magnetic resonance scans from a cohort of 20 patients with trochlear dysplasia and recurrent patellar dislocation. The objectives of this …

Towards Nuclei Segmentation With Limited Annotations, Mohammad Minhazul Haq

Computer Science and Engineering Dissertations - Archive

Nuclei segmentation is a fundamental but challenging task in histopathology image analysis. For semantic segmentation of nuclei, Convolutional Neural Network (CNN), and Vision Transformer (VT) models give very promising results. However, to successfully train fully-supervised CNN and VT models we need significant amount of annotated data which is highly rare in biomedical domain. Also, collecting an unannotated histopathology dataset first, and then manually doing pixel-level labeling is expensive, time-consuming and tedious process. Therefore, we require to discover a way for training nuclei segmentation models with unlabeled datasets. In this thesis, I present my work towards solving this critical problem by …

Investigating The Effect Of Peephole Optimizations On Binary Code Differences, Xiaolei Ren

Computer Science and Engineering Dissertations - Archive

ABSTRACT: Binary diffing is a technique used to compare and identify differences or similarities in executable files without access to source code. The potential applications of binary diffing in various software security tasks, such as vulnerability search, code clone detection, and malware analysis, have generated a vast body of literature in recent years. One of the recurring themes in binary diffing research is the evaluation of its resilience against the impact of compiler optimization, which is the most common source of syntactic differences in binary code. Despite that most binary diffing tools claim that they are immune to compiler optimization, …

On-Line Environment Adaptation For User Performance Optimization, Subharag Sarkar

Computer Science and Engineering Dissertations - Archive

In today’s fast-paced and globally connected world, businesses are creating products with more significance to user personalization and customization. This has amplified the importance of capturing and learning user preferences as more information from users can lead to the designing and development of products that will improve user engagement and performance. Numerous algorithms based on collaborative filtering and recommender systems have been used to learn user preferences, but almost all of them require big datasets to train on. This creates a dependency on collecting more and more user information which might lead to ethical considerations and privacy concerns. To solve …

Book Review: Philip Ball. The Water Kingdom: A Secret History Of China, Robert Bedeski

Comparative Civilizations Review

Over centuries scores of sinologists have sought to define the essence of China. Philip Ball addresses and goes well beyond the materialist paradigm of Karl Wittfogel’s hydraulic thesis, which described the role of water management in China as stimulating state development. In his theory, government emerged as the central institution to manage transportation, flood control and irrigation. Ball also sees water management as critical in Chinese civilization and injects his description with spiritual and moral content, drawing on poetry, art, biography and extensive reference to historical events. His book is an exploration of the role of water in China’s culture, …

Prevention And Reversal Of Elastin-Associated And Phosphate-Dependent Arterial Calcification Using Targeted Nanotherapeutics In Pre-Clinical Models, Fatema Tuj Zohora

All Dissertations

Vascular calcification can be life-threatening, involving calcium phosphate crystal deposits in the blood vessels. The calcification in the intimal layer of the arterial wall is usually associated with atherosclerotic plaque build-up that, in the advanced stage, harbors ‘dispersed’ and ‘spotty’ deposits of calcium phosphate crystals in the necrotic core of the plaque. In contrast, medial arterial calcification (MAC) can form independently of atherosclerosis and appears as ‘Railroad-like’ calcific deposits along degraded elastin lamellae in the medial layer of arteries. The mechanisms of such elastin-associated medial arterial calcification and potential therapies are the key concerns of this dissertation. MAC is common …

The Economic Impact Of Oil And Gas Production In The Permian Basin, Aditi Sarkar

Economics ETDs

The dissertation aims to analyze the economic and social consequences of unconventional oil and gas (UO&G) production in the Permian Basin, located in southeastern New Mexico and West Texas. The first paper focuses on the effect of methane reduction regulations imposed by the United States (US) government on the production of natural gas and the drilling of new wells. Specifically, the question asked is “what is the impact of methane reduction regulations on the drilling of new wells and the production of natural gas over a 40-year time horizon?” I develop dynamic optimization in a system dynamic setting to assess …

Distinguishing Servant Leadership From Transactional And Transformational Leadership, Seth-Aaron Martinez, Nahari Leija

Organizational Performance and Workplace Learning Faculty Publications and Presentations

Problem

The scholarship of leadership abounds with the affordances, limitations, antecedents, and outcomes associated with the different theories in Human Resource Development (HRD) literature. However, a clear delineation between the host of individual leadership theories does not exist. Absent is a nuanced view of the similarities, differences, and any overlap between the various leadership theories. Without a clear understanding of the relationships between leadership theories, knowing when to apply which theories and when becomes difficult.

Solution

A systematic review of the literature surrounding servant leadership (SL) through 2022 was conducted to position SL among the more extensively researched transactional and …