Digital Commons Network^™

Bench- And Pilot-Scale Corrosion Control Inhibitor Effectiveness Studies For A Community's Blended Surficial And Brackish Groundwater Supply, Paula Campesino

Electronic Theses and Dissertations, 2020-2023

The United States Environmental Protection Agency regulates the lead and copper content of a public water system's finished water at the consumer's tap, through the Safe Drinking Water Act's Lead and Copper Rule (LCR), promulgated in 1991. This rule was recently changed through the LCR Revisions (LCRR), that took effect in 2021. The more stringent requirements of the LCRR motivated the City of Sarasota, Florida (City), to work with the University of Central Florida (UCF) on a study of the municipality's finished water corrosivity. Initially, this evaluation investigated the City's existing finished water corrosivity using linear polarization resistance (LPR) measurements …

The Development Of Computational Models For Melting-Solidification Applications Using The Volume-Of-Fluid Method, Brendon Cavainolo

Electronic Theses and Dissertations, 2020-2023

Fluids-related issues in the Aerospace industry are often multiphase in scope. Numerical modeling, such as computational fluid dynamics, is used to describe these problems, as they are difficult or impossible to describe analytically. This research uses computational fluid dynamics to describe multiphase problems related to melting-solidification and particle impingement. Firstly, a numerical model was established that uses the Volume-of-Fluid method to resolve a melting/solidifying particle. This model was verified against experiments and simplified analytical models, and a mesh independence study was done to ensure the results were independent of the mesh sizing. Next, the model was applied to two separate …

Understanding, Modeling, And Simulating The Discrepancy Between Intended And Perceived Image Appearance On Optical See-Through Augmented Reality Displays, Austin Erickson

Electronic Theses and Dissertations, 2020-2023

Augmented reality (AR) displays are transitioning from being primarily used in research and development settings, to being used by the general public. With this transition, these displays will be used by more people, in many different environments, and in many different contexts. Like other displays, the user's perception of virtual imagery is influenced by the characteristics of the user's environment, creating a discrepancy between the intended appearance and the perceived appearance of virtual imagery shown on the display. However, this problem is much more apparent for optical see-through AR displays, such as the HoloLens. For these displays, imagery is superimposed …

High-Dynamic-Range And High-Efficiency Near-Eye Display Systems, En-Lin Hsiang

Electronic Theses and Dissertations, 2020-2023

Near-eye display systems, which project digital information directly into the human visual system, are expected to revolutionize the interface between digital information and physical world. However, the image quality of most near-eye displays is still far inferior to that of direct-view displays. Both light engine and imaging optics of near-eye display systems play important roles to the degraded image quality. In addition, near-eye displays also suffer from a relatively low optical efficiency, which severely limits the device operation time. Such an efficiency loss originates from both light engines and projection processes. This dissertation is devoted to addressing these two critical …

A Framework To Define And Quantify Leadership Styles Within Navy Engineering Units, Megan Praschak

Electronic Theses and Dissertations, 2020-2023

This study aimed to develop a framework for the U.S. Navy's leadership styles by assessing self-perceived leadership styles in a sample of reserve Engineering Duty Officers (EDOs) and the Senior Enlisted Leaders (SELs) in these technical units. Transformational and transactional leadership styles were examined using the Multifactor Leadership Questionnaire (MLQ) Form (Avolio & Bass, 2004), while the servant leadership style was analyzed using the Servant Leadership Self-Assessment Questionnaire (SLSQ) (Sandling, 2021). The effect of rank and the triad leadership position on leadership style was explored in this study. The survey was made available to all EDOs and SELs (n = …

Design And Control Of A Dual Active Bridge Converter For Electric Vehicle (Ev) And Photovoltaic (Pv) Applications, Md Safayatullah

Electronic Theses and Dissertations, 2020-2023

With the growing concerns of climate change due to fossil fuel-based electricity generation, solar integration to the grid is swiftly increasing. However, the intermittency of solar power is a major obstacle to harness it efficiently. Energy storage system (ESS) with its declining price over the last few years is a viable solution to address this issue. Another source of greenhouse gas emission is fossil fuel-based transportation system which is likely to be replaced by electric vehicles (EVs) in near future. To match the driving range of EVs with the internal combustion engine-based vehicle, fast and extreme fast charging infrastructure in …

Leveraging Signal Transfer Characteristics And Parasitics Of Spintronic Circuits For Area And Energy-Optimized Hybrid Digital And Analog Arithmetic, Adrian Tatulian

Electronic Theses and Dissertations, 2020-2023

While Internet of Things (IoT) sensors offer numerous benefits in diverse applications, they are limited by stringent constraints in energy, processing area and memory. These constraints are especially challenging within applications such as Compressive Sensing (CS) and Machine Learning (ML) via Deep Neural Networks (DNNs), which require dot product computations on large data sets. A solution to these challenges has been offered by the development of crossbar array architectures, enabled by recent advances in spintronic devices such as Magnetic Tunnel Junctions (MTJs). Crossbar arrays offer a compact, low-energy and in-memory approach to dot product computation in the analog domain by …

Determining The Influence Of Kids Building For Kids Workshops On Attitudes And Beliefs Of General Education Middle School Teachers Toward Students With Disabilities, Jennifer Tucker

Electronic Theses and Dissertations, 2020-2023

Children with disabilities experience barriers to meaningful engagement in science, technology, mathematics, and engineering (STEM) learning activities and course options. While inclusion is widely professed, general education teachers report being uncomfortable in adapting coursework or including children with disabilities. However, informal professional development opportunities could potentially impact general education teachers' attitudes and dispositions towards including children with disabilities. The UCF Go Baby Go Kids Building for Kids workshops offers a one-time informal professional development experience that incorporates STEM content along with concepts of disability awareness and social justice. Little to no research exists on the impact of this type of …

An Exploration Of K-8 Classroom-Based Mathematics Teacher Leader Development, Treshonda Rutledge

Electronic Theses and Dissertations, 2020-2023

This study investigated classroom-based mathematics teacher leader (CBMTL) development through analysis of interview and focus group transcripts, results from a Mathematics Teacher Leadership Experiences survey, application materials, and an evaluation report for an equity-focused, research-to-practice doctoral program centered on developing CBMTLs. A multiple case study was conducted to interpret and understand how K-8 mathematics teachers identified and described ways in which their participation in the program developed them as CBMTLs. Findings suggest that mathematics teachers develop as mathematics teacher leaders in stages and highlight the effectiveness of the research-to-practice partnership model as an impactful pathway for developing CBMTLs. Themes from …

Examining Direct Load Control Within Demand Response Programs, Maria Bonina Zimath

Honors Undergraduate Theses

The power system is a complex entity with unique plant designs, control systems, and market strategies. For many years, engineers have developed advanced technology to keep the grid efficient and balanced. With the rise of renewable sources, some new technology and programs must be developed to keep the quality of the power system. Unlike traditional power plants, renewable energy is highly dependent on environmental factors, such as sunlight and wind, meaning the generation depends on an unpredictable source of fuel. As the grid moves to more sustainable sources, the power market faces a growing challenge of less control over the …

Biomarker Identification For Breast Cancer Types Using Feature Selection And Explainable Ai Methods, David E. La Rosa Giraud

Honors Undergraduate Theses

This paper investigates the impact the LASSO, mRMR, SHAP, and Reinforcement Feature Selection techniques on random forest models for the breast cancer subtypes markers ER, HER2, PR, and TN as well as identifying a small subset of biomarkers that could potentially cause the disease and explain them using explainable AI techniques. This is important because in areas such as healthcare understanding why the model makes a specific decision is important it is a diagnostic of an individual which requires reliable AI. Another contribution is using feature selection methods to identify a small subset of biomarkers capable of predicting if a …

Understanding Changes In Land Use Patterns At A Parcel Level In Central Florida Counties (Orange, Seminole, Osceola), Youssef Mohamed Abdelaziz Elsebaie

Electronic Theses and Dissertations, 2020-2023

In Florida, a state with significant population growth, it is essential to understand how land use change and transportation interact. Understanding these interactions between land use and transport is useful for transportation planners and land use modelers. Hence, in this research, we attempt to quantify the impact of the transportation system on land use and vice-versa. The research, using high-resolution land use data from 2011 to 2019, builds a binary logistic regression model of land use change. The model accounts for various independent variables, including socio-demographic attributes, built environment characteristics, and transportation network variables. The data set covers GIS data …

Detonability Of A Rotating Detonation Combustor Seeded With Carbon/Hydrocarbon Particles At Fringe Operating Conditions, Matthew Hopwood

Electronic Theses and Dissertations, 2020-2023

The Rotating Detonation Combustor (RDC) has, in recent years, been a subject of great interest in the pressure-gain combustion research community. Researchers have been investigating the RDC as a potential improvement over current combustors in today's turbomachinery-based power generation systems. With the theoretical efficiency boost that detonations provide over deflagrating combustors, RDCs have the promise to be a next step in fuel/cost savings in the power generation industry. One mode of research to push an RDCs capabilities is the potential use of combustible carbon/hydrocarbon solid particles in addition to liquid or gaseous fuels. These particles are a source of high …

The Role Of Oxygen Impurities In Γ-Phase Calcium Lanthanum Sulfide For Infrared Applications, Alexandros Kostogiannes

Graduate Thesis and Dissertation 2023-2024

Calcium lanthanum sulfide (CLS) has been identified as a candidate material for various optical applications due to its wide transmission range, high refractive index, desirable thermo-optic properties, and refractory behavior. Implementation of CLS in optical systems has remained unrealized due to various difficulties in the synthesis and bulk fabrication of this material. The key challenge facing the development of CLS is the incorporation of oxygen and the presence of unwanted secondary phases related to the lack of control of stoichiometric variations across the ternary phase diagram. Though these difficulties have been previously discussed in the processing of CLS, the exact …

A Generalized Accelerated Failure Time Model To Predict Restoration Time From Power Outages, Tasnuba Binte Jamal

Graduate Thesis and Dissertation 2023-2024

Major disasters such as wildfire, tornado, hurricane, tropical storm, flooding cause disruptions in infrastructure systems such as power outage, disruption to water supply system, wastewater management, telecommunication failures, and transportation facilities. Disruptions in electricity infrastructures have negative impacts on sectors throughout a region, including education, medical services, financial, and recreation sectors. In this study, we introduce a novel approach to investigate the factors which can be associated with longer restoration time of power service after a hurricane. Considering restoration time as the dependent variable and utilizing a comprehensive set of county-level data, we have estimated a Generalized Accelerated Failure Time …

Enabling Large-Scale Transportation Electrification For Shared And Connected Mobility Systems, Md Rakibul Alam

Graduate Thesis and Dissertation 2023-2024

Owing to advancements in technology, substantial investments within the automotive industry, and the formulation of supportive state policies, the future landscape of the transportation sector is poised to witness a shift from traditional internal combustion engine vehicles (ICEVs) to electric vehicles (EVs). While EVs have made inroads in the market, they still face significant hurdles in the form of range anxiety and prolonged charging durations, inhibiting their widespread adoption. To tackle these challenges, a comprehensive approach to smart transportation electrification is proposed, emphasizing the pivotal roles of infrastructure development, particularly in the allocation of charging stations, and strategic operational decisions, …

Optimizing Biomechanical Models: Estimation Of Muscle Tendon Parameters And Ankle Foot Orthosis Stiffness, Sepehr Ramezani

Electronic Theses and Dissertations, 2020-2023

The complexity of the human musculoskeletal system presents challenges in accurately identifying its characteristics, particularly due to the presence of redundant actuators on a single joint. Non-invasive measures are necessary to overcome these challenges. Optimization algorithms have emerged as a crucial tool to advance subject-specific musculoskeletal modeling allows a more realistic representation of biomechanical behaviors, enhancing our understanding of human movement and enabling better clinical decision-making. Furthermore, optimization algorithms play a vital role in customizing rehabilitation and assistive devices, such as orthoses and prostheses. The current ankle-foot orthosis (AFO) stiffness measurement methods require bulky, complex designs, and often permanent modification …

Assessment Of Midblock Pedestrian Crossing Facilities Using Surrogate Safety Measures And Vehicle Delay, Nafis Anwari

Graduate Thesis and Dissertation 2023-2024

This dissertation has contributed to the pedestrian safety literature by assessing and comparing safety benefits and traffic efficiency among midblock Rectangular Rapid Flashing Beacon (RRFB) and Pedestrian Hybrid Beacon (PHB) sites. Video trajectory data were used to calculate pedestrian Surrogate Safety Measures (SSMs) and vehicles' delay. Regression models of SSMs and vehicles' delay revealed that PHB sites offer more safety benefits, at the expense of increased vehicles' delay, compared to RRFB sites. The presence of the PHB, weekday, signal activation, lane count, pedestrian speed, vehicle speed, land use mix, traffic flow, time of day, and pedestrian starting position from the …

Material Appearance Modeling For Physically Based Rendering, Alexis Benamira

Graduate Thesis and Dissertation 2023-2024

Photorealistic rendering focuses on creating images with a computer that imitates pictures of reallife scenes as faithfully as possible. To achieve this, rendering algorithms require incorporating accurate modeling of how light interacts with various types of matter. For most objects, this model needs to account for the scattering of the light rays. However, this model falls short when rendering objects of sizes smaller or comparable to the wavelength of the incident light. In this case, new phenomena such as diffraction or interference are observed and have been characterized in optics. Digital rendering of those phenomena involve different light representations than …

Modeling Behavior And Vaccine Hesitancy For Predicting Daily Vaccination Inoculations Using Trends, Case, Death, And Twitter Sentiment Data, Talal Daghriri

Electronic Theses and Dissertations, 2020-2023

Over the past 100 years, epidemiological models have evolved to incorporate greater facets of the process. With the advent of social networking, massive computational power, population sentiment analysis can now be added to the epidemiological modeling process. Sentiment analysis is greater understanding of the fears, uncertainties, motivation, and trends of the public with respect to vaccination and associated events. Lack of public confidence in the efficacy of models, safety of vaccines, and appropriateness of policies confounds vaccine inoculation prediction. Sentiment analysis of social media is a seminal technique that accesses shared users' contents and tweets on the Twitter platform for …

Machine Learning Algorithms For Molecular Signature Identification With High-Throughput Genome Sequencing Data, Jiao Sun

Electronic Theses and Dissertations, 2020-2023

Powered by the high-throughput genomic technologies, the RNA sequencing (RNA-Seq) method is capable of measuring transcriptome-wide mRNA expressions and molecular activities in cells. Elucidation of gene expressions at the isoform resolution enables the detection of better molecular signatures for phenotype prediction, and the identified biomarkers may provide insights into the functional consequences of disease. This dissertation research focuses on developing advanced machine learning algorithms for mining large-scale RNA-Seq data in cancer transcriptome analysis. A platform-integrated model for transcript quantification (IntMTQ) is developed to improve the performance of RNA-Seq on isoform expression estimation. IntMTQ provides more precise RNA-Seq-based isoform quantification, and …

Heat Release And Flame Scale Effects On Turbulence Dynamics In Confined Premixed Flows, Max Fortin

Electronic Theses and Dissertations, 2020-2023

As industry transitions to a net-zero carbon future, turbulent premixed combustion will remain an integral process for power generating gas turbines and are also desired for aviation engines due to their ability to minimize pollutant emissions. However, accurately predicting the behavior of a turbulent reacting flow field remains a challenge. To better understand the dynamics of premixed reacting flows, this study experimentally investigates the evolution of turbulence in a high-speed bluff-body combustor. The combustor is operated across a range of equivalence ratios from 0.7-1 to quantify the role of heat release and flame scales on the evolution of turbulence as …

An Experimental Mixed Methods Pilot Study For U.S. Army Infantry Soldiers - Higher Levels Of Combined Immersion And Embodiment In Simulation-Based Training Capabilities Show Positive Effects On Emotional Impact And Relationships To Learning Outcomes, Fred Martin, Jr

Electronic Theses and Dissertations, 2020-2023

This pilot study examines the impact of combined immersion and embodiment on learning and emotional outcomes. The results are intended to better enable U.S. Army senior leaders to decide if dismounted infantry Soldiers would benefit from a more immersive simulation-based training capability. The experiment's between-subject design included a sample of 15 participants randomly assigned to one of three system configurations representing different levels of combined immersion and embodiment. The control group was a typical desktop, and the two experimental groups were a typical configuration of a Virtual Reality headset (VR) and a novel configuration using VR supported by an omnidirectional …

Process Optimization And Characterization Of P-Type Copper Indium Oxide And Copper Chromium Oxide Transparent Conducting Thin Films And Its Applications, Fnu Sreeram Sundaresh

Electronic Theses and Dissertations, 2020-2023

Transparent conducting oxides (TCO) are a unique class of compounds that combine the properties of being optically transparent but at the same time are electrically conductive. TCOs are used in a variety of applications such as transparent contacts for solar cells, electrochromic windows, low-e windows, optoelectronic devices, light-emitting diodes, optical displays, UV sensors, defrosting windows, etc. By controlling doping and by adjusting the donor/acceptor levels, the conductivity of TCOs can be tuned from insulating via semiconducting to conducting. Various properties of TCOs such as optical transparency, bandgap, and electrical conductivity can be controlled using the aforementioned process. This concept paved …

Activist-Casual Game Design: Iterating Serious Games Through Research-Creation, Daniel J. King

Graduate Thesis and Dissertation 2023-2024

How can activists and scholars design serious game projects that attract and engage people, that are inviting for many types of players, and that empower players to create positive change? My hypothesis was that the Activist-Casual Game Design Framework I published in 2021 could facilitate this work. I took a design-based research approach to answer my research question by way of demonstration and self-reflection through a creative case study of the production of an activist-casual game called Climate Somnia. Chapter 1 explains the literature review and synthesis behind the creation of the original framework, and Chapter 2 reviews the …

Beyond Local Food Consumption: The Impact Of Local Food Consumption Experience On Cultural Competence, Eudaimonia And Behavioral Intention, Bingna Lin, Saerom Wang, Xiaoxiao Fu, Xiaoli Yi

Faculty Scholarship and Creative Works

Purpose: This paper aims to explore the relationships among local food consumption experience, cultural competence, eudaimonia, and behavioral intention. Building upon acculturation theory, need hierarchy theory and self-determination theory, the current study develops a conceptual model of local food consumption as international tourists' acculturation process.

Design/methodology/approach: This study collects data from 305 Chinese outbound tourists and uses partial least squares-structural equation modeling to examine the developed model.

Findings: The findings reveal a significant effect of the local food consumption experience, consisting of novel, authentic, sensory and social dimensions, on cultural competence, which subsequently evokes eudaimonia and behavioral response toward local …

War On The Bay: Determining The Existence Of Watershed Moments Within The Shipyards In Tampa, Florida During World War Ii, Connor E. Farley

Graduate Thesis and Dissertation 2023-2024

With the Great Depression on one side and prosperity on the other, historians of World War II have debated its effects on American society and have asked if it represented a watershed moment. While the war clearly disrupted American life and opened new opportunities for many, its role as a transformative event remains contested. This examination of the Tampa shipyards utilizes the theoretical and methodological lenses of social history to facilitate an analysis based on a chronological approach. This analysis centers on the situation in Tampa before, during, and after World War II, and in doing so it assesses the …

Chatgpt Assignments To Use In Your Classroom Today, Kevin Yee, Kirby Whittington, Erin Doggette, Laurie Uttich

UCF Created OER Works

No abstract provided.

Time-Specific Safety Performance Functions For Different Advanced Traffic Management Strategies, Jingwan Fu

Electronic Theses and Dissertations, 2020-2023

Time-specific Safety Performance Functions (SPFs) were proposed to achieve accurate and dynamic crash frequency predictions and bridge the gap between annual crash frequency prediction and real-time crash likelihood prediction. This research proposed time-specific SPFs considering the temporal variation in crashes and traffic characteristics. Firstly, the developed time-specific SPFs that include different ATM strategies (i.e., HOV, merge, diverge and reversible lanes segments) were investigated in this study. The results indicate that the traffic turbulence during specific hours would relate to crash occurrence. Further, the variables that represent the speed and occupancy differences between the HOV lanes/reversible lanes and general-purpose lanes were …

Radioprotectant Ceria Nanoparticles Drug Delivery System To Reduce Reactive Oxygen Species Levels And Mitigate Spaceflight Osteopenia, Balaashwin Babu

Electronic Theses and Dissertations, 2020-2023

In the extreme environment of space, radiation induced health issues is a major concern. The ability to induce higher levels of free radicals and reactive oxidative species (ROS) are factors to be addressed. Ceria nanoparticles (CNPs) can provide a means to scavenge ROS through regenerative redox coupling that occurs on the surface and acts as a radioprotectant. Additionally, the defect levels in CNP can be categorized by the Ce3+/Ce4+ ratio with a high ratio indicating superoxide scavenging, a radical species with high oxidative potential. However, engineering a specialized Ce3+ NP often requires a harsh reducing agent. We hypothesized a wet-chemical …