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The Effect Of Fixed Time Delays On The Synchronization Phase Transition, Shaizat Bakhytzhan

USF Tampa Graduate Theses and Dissertations

Nature is full of synchronization phenomena, which are essential to many scientific fields like biology, chemistry, physics, and neuroscience. The Kuramoto model is a well-known theoretical model that helps explain the fundamental ideas behind synchronization dynamics [6]. Nevertheless, in practical situations, systems frequently display intrinsic latency, which can greatly impact their behavior during synchronization. This insight inspired our work, which looks at the results of adding temporal delays to the Kuramoto model. In particular, we investigate how the system’s synchronization dynamics are affected by delays. We shed light on the mechanisms underpinning synchronization in the face of temporal delays and …

Context-Aware Affective Behavior Modeling And Analytics, Md Taufeeq Uddin

USF Tampa Graduate Theses and Dissertations

Affective computing (AC) is a sub-domain of AI that has the potential to assist people by assessing mental states and making appropriate recommendations to patients, loved ones, caregivers, and domain experts. Humans usually produce an enormous amount of data (such as face videos) every day. One of the major challenges for affective computer vision is to efficiently deal with high volumes of data to facilitate automated model development. To cope with this challenge, we developed computer vision algorithms that measure the expressivity of the human face from video data. More precisely, the developed algorithms can map complex affect information from …

Quandle Rings, Idempotents And Cocycle Invariants Of Knots, Dipali Swain

USF Tampa Graduate Theses and Dissertations

Quandles are sets with self-distributive binary operations that axiomatize the three Reidemeister movesin classical knot theory. In an attempt to bring ring theoretic techniques to the study of quandles, a theory of quandle rings analogous to the classical theory of group rings where several interconnections between quandles and their associated quandle rings have been explored. Functoriality of the construction implies that morphisms of quandle rings give a natural enhancement of the well-known quandle coloring and quandle 2 cocycle invariant of knots and links.

The dissertation is structured into two main parts. In the first part, we delve into quandle rings …

Beach Processes Controlling Erosional Hotspots And Their Influences On Beach Nourishment Performances: A Case Study Along West-Central Florida Barrier Island Beaches, Sophia Gutierrez

USF Tampa Graduate Theses and Dissertations

This study examines the long-term performance of repeated beach nourishment over an approximately 35-year period at two barrier islands, Sand Key and Treasure Island along the west-central Florida coast, USA. Five cycles of beach nourishment on Sand Key and six on Treasure Island were conducted during the study period. Three erosional hotspots were identified along a combined 14-km stretch of the nourished beach. The processes that cause the erosional hotspot were examined through numerical modeling of nearshore wave and current fields.

The most recent three nourishments since 2006 were monitored systematically by this study. Beach profiles were surveyed bimonthly to …

Comparative Analysis Of Time Series Models On U.S. Stock And Exchange Rates: Bayesian Estimation Of Time Series Error Term Model Versus Machine Learning Approaches, Young Keun Yang

USF Tampa Graduate Theses and Dissertations

This study presents a comparative analysis of contemporary applications of time series models, focusing on the Bayesian approach. In contrast to many nonparametric studies, the Bayesian approach circumvents the common issue of bandwidth selection by offering systematic estimation and avoiding ad hoc methods. Specifically, we delve into the Bayesian approach for estimating the autocovariance function of a time series model’s error term. Traditional time series models often make the unrealistic assumption of a constant error term. Furthermore, models such as autoregressive conditional heteroskedasticity (ARCH) and general autoregressive conditional heteroskedasticity (GARCH) address the limitation of constant variance by assuming an autoregressive …

Iron Isotope Transformations In Saanich Inlet, Claire Onak

USF Tampa Graduate Theses and Dissertations

Iron (Fe) is required for many biogeochemical processes, with Fe bioavailability and chemistry being controlled by redox reactions that transform Fe between oxidation states and dissolved and particulate phases. In oxic seawater, Fe is present in the Fe(III) oxidation state, mainly as Fe oxyhydroxides. Under anoxic marine conditions, such as margin sediments under oxygen minimum zones or restricted basins with anoxic bottom water, Fe(III) is reduced to Fe(II), which is highly soluble and can be present at high concentrations ([Fe]). Fe isotope ratios (δ56Fe relative to IRMM-14) can be used to characterize Fe redox transformations, constrain Fe sources of Fe …

Thermal Ecology And Swimming Performance Of Native Tadpoles Dryophytes Femoralis In Central Florida, Jessalyn Aretz

USF Tampa Graduate Theses and Dissertations

Urbanization and climate warming have contributed to global amphibian declines in recent decades. Amphibians are particularly vulnerable to climate and urban-induced warming because their physiological processes are dependent on temperature across all life stages, but few studies have been done on tadpole responses to warming in comparison to adult responses. The study objective was to determine how the thermal ecology and swimming performance of a native Florida tadpole varied with rearing temperature and urban level, and whether these traits are plastic or adaptive. We collected eggs from wild populations of pine woods treefrog (Dryophytes femoralis) tadpoles at an urban and …

Advancing Depth-Storage-Discharge Modeling In Regional Hydrology, Fahad Alshehri

USF Tampa Graduate Theses and Dissertations

This dissertation presents the development of an innovative approach to populating rating characteristics and supporting hydrologic modeling, designed to simplify complex real-world hydrological systems and accurately estimate their responses to rainfall, runoff, baseflow and evaporation stresses. The core of this research addresses the challenges inherent in characterizing hydrography elements in hydrologic modeling, particularly in regions lacking comprehensive stream reach survey data, flow and stage. This issue is pronounced in areas with extensive wetland hydrography, where traditional modeling requires intensive manual calibration, and course rating data that are often unavailable. To overcome these challenges, this study introduces a novel procedure that …

Individual Behavioral Modeling Across Games Of Strategy, Logan Fields

USF Tampa Graduate Theses and Dissertations

An individual’s actions in a particular environment and with specified resources can reveal their decision-making tendencies and patterns, and by analyzing the variations in cognitive traits among individuals, it may be possible to identify trends that can foretell their future behaviors. This can be a powerful tool in various fields including cognitive modeling, player analytics, computer security, and threat detection. Collectible card games are a fruitful test space for studying cognitive differences in decision-making, as they can have clearly defined and replicable environments and large player bases. As such, in this work, I explore the potential of using two virtual …

Introductory Chemistry Student Success: Evaluating Peer-Led Team Learning And Describing Sense Of Belonging, Jessica D. Young

USF Tampa Graduate Theses and Dissertations

Identifying approaches that make science and engineering education broader and more inclusive is core to discipline based education research. Both fundamental and applied research are important in advancing a STEM education that retains the necessary scientists of the U.S.’s future. Thus, the major goal of this work was to evaluate and describe efforts that promote student success within introductory STEM courses. This began with applied research by utilizing quantitative analyses like case-matching, logistic regression, independent sample t-tests, and repeated measures while evaluating the efficacy of peer-led team learning (PLTL). Later, this work delves into qualitative approaches to answer fundamental research …

Home Is Where The Work Is: How Biases In Managers’ Resource Allocation Decisions Affect Task Performance In Remote Work Environments, Richard D. Mautz Iii

USF Tampa Graduate Theses and Dissertations

As the use of remote and hybrid work arrangements continues to grow, it is important to understand how these arrangements can yield performance. In this paper, I conduct two studies to examine how the remote work environment affects managers’ task assignment decisions across different task types and how those decisions affect workers’ task performance. First, I survey managers, in both a cross-section of industries and specifically in accounting, to study the effect of remote work on their task assignment decisions. Consistent with prior literature and economic theory, I predict and find that managers are more inclined to assign generative tasks …

Explorations On Non-Covalent Interactions: From Supramolecules To Drug-Like Molecules, Zhanpeng Zhang

USF Tampa Graduate Theses and Dissertations

Non-covalent interactions are everywhere in our material world. From the microstructures of organisms to the functional materials used in industrial production, whenever matter exists, there are non-covalent interactions between the molecules that build up the matter.The exploration of non-covalent forces helps people understand the intrinsic principles of life processes, it can be applied to create new supramolecular materials as well. Supramolecular chemistry is a research field focusing on the properties and applications of non-covalent interactions. Various non-covalent interactions, such as hydrogen bonds, metal-ligand coordination, π-π interaction, hydrophobic interaction, etc., are objects of research in supramolecular chemistry.

Not only supramolecular chemists, …

On The Subelliptic And Subparabolic Infinity Laplacian In Grushin-Type Spaces, Zachary Forrest

USF Tampa Graduate Theses and Dissertations

This thesis poses the ∞-Laplace equation in Grushin-type spaces. Grushin-type spaces G are defined by the vector fields which serve as a basis for their tangent spaces; by weighting the canonical (Euclidean) directional vectors {∂/∂x_i}ⁿ_i=1 by functions ρ_i that obey certain technical assumptions, we produce a class of metric spaces in which certain directions may not be accessible at all points in the space. We prove the existence and uniqueness of viscosity solutions to both Dirichlet problems and Cauchy-Dirichlet problems involving the∞-Laplacian over bounded Grushin-type domains. The main tool in proving uniqueness of …

Interfacial Magnetism And Anisotropy In Dirac And Weyl Semimetals, Noah Schulz

USF Tampa Graduate Theses and Dissertations

Semimetals have gained intense interest recently due to their exotic magnetic and electronic properties. One of the most widely studied semimetals is graphene, a Dirac semimetal. The utilization of graphene in devices and sensors requires interfacing it with other materials, which may induce potentially strong interfacial effects. Furthermore, graphene alone does not possess magnetic order. Studying the interfacial effects between graphene and magnetic materials is therefore of great importance in the application of graphene to meet modern technological needs. Furthermore, by understanding the fundamental interfacial physics between graphene and magnetic materials, new properties can be unlocked, broadening the possible applications …

Development And Evaluation Of Novel Applications For The Ethos Cbct-Guided Online Adaptive Radiotherapy System, Nour Nasser

USF Tampa Graduate Theses and Dissertations

Radiation therapy (RT) is an important pillar of modern cancer treatment, in neoadjuvant, curative, adjuvant, and palliative settings. The physics underlying RT is ionizing radiation that produces charged particles, which deposit their energy in the tissues they pass through. This energy results in unrepairable DNA damage resulting in the death of cancer tissue. The aim of RT is to deliver the desired radiation dose to the tumor while maximizing normal tissue sparing. Over the past decades, physics, engineering, and computational improvements has allowed advancement of external beam RT techniques, for example from 2D RT to 3D RT to now intensity …

Dissolved Nitrogen Removal In Biochar Amended, High Permeability Media For Urban Stormwater Treatment, Mark Vicciardo

USF Tampa Graduate Theses and Dissertations

Nutrient pollution in stormwater drives the eutrophication of inland and costal waterbodies which leads to sea grass retreat and the proliferation of harmful algal blooms (HAB). These anthropogenic effects destabilize ecosystems, and some HABs can pose direct human health risk. Bioretention, or the storage and controlled discharge of stormwater run-off in an ecologically engineered setting, is a potential solution to this problem. However, it relies heavily on the settling of particles as a nutrient removal mechanism, and thus struggles with pollutants, such as dissolved nitrogen, which is a particular problem in Florida where the geological prominence of phosphorus leaves nitrogen …

Bird Strike Hazard Assessment For The Tampa International Airport, Florida, Usa, Yakubu Ogwu Isah

USF Tampa Graduate Theses and Dissertations

Managing wildlife at airports poses a challenge for ensuring safety for aviation traffic. Airports, with their surrounding habitats and infrastructure, serve as attractants for avian species. Threats created by these species have led managers to develop management techniques in and around airports (DeVault et al 2013). One approach is the use of geographic information systems (GIS) for analyzing avian strike data and airport bird surveys. Spatial analysis of strike data identifies species of threat by categorizing strike occurrence, species sizes, phase of flight, and risk of damage. In addition, GIS can be used to map hotspots of bird strikes. These …

Semi-Automated Cell Annotation Framework Using Deep Learning, Abhiram Kandiyana

USF Tampa Graduate Theses and Dissertations

Unbiased stereology refers to a field of applied mathematics \cite{intro-to-stereology} focused on accurate (model and assumption-free) quantification of three-dimensional (3D) objects, typically based on their appearance in 2D sections (planes) through the objects. In the biological sciences, these techniques are widely used for making unbiased estimates of arbitrary-shaped (stochastic) objects such as stained cells, blood vessels, region volumes, etc., in tissue sections through a region of interest (ROI).

This fundamental methodology is widely used for evaluating structural changes that occur in diseases, aging, and pharmaceutical interventions, thereby ensuring reliable outcomes. In terms of limitations, stereology is tedious, time- and labor-intensive, …

Automatic Image-Based Nutritional Calculator App, Kejvi Cupa

USF Tampa Graduate Theses and Dissertations

Nutrition plays a pivotal role in shaping an individuals’ health and quality of life, making the evaluation of dietary intake crucial for promoting healthier lifestyle choices. Various solutions, particularly mobile apps, have been developed to facilitate the process of dietary estimation. Accurate nutritional intake assessment relies on two key components: ingredient recognition and food portion estimation. For a mobile app to offer a comprehensive solution for automatic nutritional assessment, it must address both components.

In this work, we focus on a mobile app pipeline: the semi-automatic pipeline which focuses on automatic food ingredient recognition. This pipeline integrates state-of-the-art models for …

Utilizing Machine Learning Techniques For Accurate Diagnosis Of Breast Cancer And Comprehensive Statistical Analysis Of Clinical Data, Myat Ei Ei Phyo

USF Tampa Graduate Theses and Dissertations

Breast cancer represents a formidable malignancy, presenting a substantial threat to global health and individual well-being. Conventionally, it is widely held that the prognosis for breast cancer patients hinges predominantly upon the timing of diagnosis and the extent of cancer progression, typically delineated by its stage. However, emerging evidence from robust regression and machine learning analyses challenges this prevailing notion. The results indicate that survival months cannot be solely attributed to diagnosis and socio-economic factors. Instead, additional variables such as existing diseases and treatment complexities may contribute to the intricate landscape of breast cancer outcomes.

This research aims to delve …

Predicting Gender Of Author Using Large Language Models (Llms), Satya Uday Sanku

USF Tampa Graduate Theses and Dissertations

The advent of text data from social media, blogs, movie reviews, and other textual sources has opened new avenues for research, particularly in the domain of Author Profiling. Author Profiling helps in Capturing the Stylistic features and also useful for analyzing the required elements in the written text. This Study addresses one of the tasks in Author Profiling which is termed as gender detection or Classification of Gender from Text. The main goal of this research is to obtain valuable and relevant gender characteristics that will accurately classify the Author’s gender of a review extracted from an Anime Review website. …

Investigating The Causes Of Lake Level Variability On A Modern Carbonate Platform, Natalie M. Salazar

USF Tampa Graduate Theses and Dissertations

Lakes on carbonate islands are known to reduce freshwater lens volumes and alter freshwater lens distribution; however, the magnitude and controlling factors between lake and freshwater lens interactions remain poorly understood. Since freshwater lenses are thin and can be fragmented by lakes in small carbonate islands, it is important to understand the magnitude of exchange between lakes and the freshwater lens to understand potential groundwater depletion. This study utilized high temporal resolution water levels and meteorological data to quantify monthly water budgets for seven lakes on San Salvador Island, The Bahamas. The monthly water budgets accounted for rainfall, potential evaporation, …

Interrelationships Among Local Values Of Wet Bulb Globe Temperature, Heat Index, And Adjusted Temperature, Andrea Giraldo

USF Tampa Graduate Theses and Dissertations

Occupational heat stress significantly affects outdoor workers who face challenges due to increased heat exposure. Because of the prevalence of heat illness, it is important to measure heat stress for outdoor workers. Monitoring occupational heat stress most often relies on the Wet Bulb Globe Temperature (WBGT) measure. Heat Index (HI) is a widely used measure to account for air temperature and humidity. Adjusted Temperature (Tadj) considers air temperature, humidity and estimates radiant heat. There is interest in predicting WBGT from HI and HI from WBGT. This study builds on previous USF research by Bernard and Iheanacho and Irvin to evaluate …

The Effect Of The Covid-19 Pandemic On The Environmental Perceptions Of College Students, Sydney H. Kaylor

USF Tampa Graduate Theses and Dissertations

In this study, the environmental perception changes in college students during the COVID-19 pandemic were investigated. During the almost worldwide lockdown between March and December 2020, many students experienced dramatic changes in their socioeconomic life that have affected their well-being, ability to learn, and environmental perceptions. Students were sent home from college campuses, many businesses were shut down, and changes were seen in the environment throughout the world. The many industries and businesses that were shut down decreased the pollution that was in the atmosphere, in our water, and on the land. In many places, lockdown policies lead to improved …

Metatranscriptomic Insights Into The Interaction Between Microcystis Blooms And Hydrogen Peroxide, Taylor L. Hancock

USF Tampa Graduate Theses and Dissertations

For this dissertation I studied the interactions of hydrogen peroxide and cyanobacterial harmful algal blooms (cHABs) dominated by Microcystis in the Caloosahatchee River, FL. Specifically, I examined how taxonomic and functional succession relates to both natural hydrogen peroxide dynamics and hydrogen peroxide added to the environment as a cHAB treatment. Chapter 2 investigated how taxonomic succession and gene expression patterns relate to blooms and associated elevated hydrogen peroxide concentrations. The results showed that gene expressions related to cyanobacterial growth were positively correlated with hydrogen peroxide. The genes identified included enzymes capable of hydrogen peroxide generation which were expressed by blooming …

The Role Of Muslim Women In Nigeria’S Socioeconomic Development Through The Implementation Of The United Nations Sustainable Development Goals, Faqiat Afolake Adeaga

USF Tampa Graduate Theses and Dissertations

This research explores the often underestimated yet pivotal role of Muslim women in propelling socio-economic development in Nigeria, specifically focusing on the implementation of the United Nations Sustainable Development Goals (SDGs). The primary research question seeks to comprehend the transformative impact of faith-based women-led NGOs, including Ansar-ud- Deen, Nawair-ud-Deen, FOMWAN, and NASFAT, on Muslim women's empowerment and their contribution to SDG1 (extreme poverty), SDG3 (health), SDG4 (education), and SDG5 (gender equality) in Nigeria. Simultaneously, the secondary research question explores successful strategies employed by these organizations in empowering Muslim women, with a keen focus on potential areas for improvement. Incorporating research …