Physical Sciences and Mathematics Commons^™

Explainable And Cooperative Autonomy Across Networks Of Distributed Systems, Peter Joseph Jorgensen

USF Tampa Graduate Theses and Dissertations

Large networks of complex systems-of-systems are commonplace and evermore present in both mundane and extraordinary facets of human existence. From the exponential growth of connectivity via the internet and other information networks, to the miniaturization of computers and sensors, to cross-domain sensor and communication networks, these networks of distributed systems-of-systems (NDSS) present incredible benefits and challenges. Autonomy is perhaps the most important and most difficult to achieve enabling technology for efficient performance of the NDSS. Giving each individual agent in a network the ability to manage its internal state in dynamic operating environments and in pursuit of multiple complex and …

Methods In Discrete Mathematics To Study Dna Rearrangement Processes, Lina Fajardo Gómez

USF Tampa Graduate Theses and Dissertations

In this work, we introduce novel tools to study DNA recombination pathways and measure their complexity. Genome rearrangement in some ciliate species can be modeled by subword pattern deletions in double-occurrence words (DOWs), words where each symbol appears exactly twice. The iterated deletions can be represented by a graph whose vertices are DOWs connected by an edge if one word can be obtained from the other through a pattern deletion. On this graph, called the “word graph”, we build a complex comprised of cells defined by Cartesian products of simplicial digraphs where we define a boundary operator and compute homology …

Data-Driven Analytical Predictive Modeling For Pancreatic Cancer, Financial & Social Systems, Aditya Chakraborty

USF Tampa Graduate Theses and Dissertations

Pancreatic cancer is one of the most deathly disease and becoming an increasingly commoncause of cancer mortality. It continues giving rise to massive challenges to clinicians and cancer researchers. The combined five-year survival rate for pancreatic cancer is extremely low, about 5 to 10 percent, owing to the fact that a large number of the patients are diagnosed at stage IV when the disease has metastasized. Our study investigates if there exists any statistical significant difference between the median survival times and also the survival probabilities of male and female pancreatic cancer patients at different cancer stages, and irrespective of …

Ice Deposits In Lava Tubes From West-Central New Mexico As Archives Of Past Volcanic Eruptions And Climate Change, Quinton Z. Vitelli-Hawkins

USF Tampa Graduate Theses and Dissertations

The Southwest of the United States is currently in a megadrought phase. Recent studies have shown that three of the most severe droughts of the last two millennia have occurred in the last 120 years, while geo-archaeological evidence suggests there were five megadroughts just from 150 to 950 CE. To try to better understand the causes of the droughts across the Southwest, a 110-cm long ice core was drilled from an ice deposit in a lava tube (Cave 29) from El Malpais National Monument in west-central New Mexico. The δ18O values in the ice core (ranging from −11.78 to −3.54‰) …

Assessing Environmental Sensitivity In San Diego County, California, For Bird Species Of Special Concern, Eda Okan Kilic

USF Tampa Graduate Theses and Dissertations

It is widely recognized that desertification constitutes one of the biggest environmental problems on Earth. Desertification negatively impacts the future of humans and other living things all over the globe. Therefore, the assessment of desertification is essential to both monitor and combat desertification. A number of models are routinely applied to assess desertification. The MEDALUS model is one of the most popular approaches, identifying desertification risk based on an environmentally sensitive area index (ESAI) that integrates climate, vegetation, soils, groundwater, and socio-economic factors to obtain an overall rating. The goal of this study was to measure the potential impacts of …

Nonparametric Estimation Of Transition Probabilities In Illness-Death Model Based On Ranked Set Sampling, Ying Ma

USF Tampa Graduate Theses and Dissertations

The ranked set sampling (RSS) design is applied widely in agriculture, environmental science, and medical research where the exact measurements of sampling units is costly, but sampling units can be ranked by a correlated concomitant variable. RSS is usually a cost-efficient alternate to simple random sampling (SRS) for selecting more representative samples. This study presents a novel methodology to investigate the nonparametric estimation of transition probabilities in illness-death model using the RSS design. We study the Aalen–Johansen estimator of transition probabilities in illness-death Markov model based on RSS design under random right censoring time and propose nonparametric estimators of the …

Antibiotic-Resistant Escherichia Coli And EnterococcusSpp. In Sand And Water At Tampa Bay Beaches, Jennifer K. Sabater

USF Tampa Graduate Theses and Dissertations

As antibiotic resistance in the environment continues to rise there is an increased concern that infections may become harder to treat as bacteria acquire genes for multidrug resistance. Recreational beach waters in the Tampa Bay area are routinely monitored by the Florida Department of Environmental Protection for the presence of fecal indicator bacteria (FIB) such as Escherichia coli and enterococci. Exceedances of beach action values (BAV) 235 CFU/100 mL (E. coli) and 70 CFU/100 mL (enterococci) indicate the presence of fecal contamination which is associated with an increased risk of disease for beachgoers. Antibiotic-resistant E. coli and Enterococcus spp. have …

Improved Performance Of Silica-Supported La0.5Ba0.5Feo3 In The Reverse Water Gas Shift - Chemical Looping Process For Carbon Dioxide Reduction – A Density Functional Theory Study, Jiawei Guo

USF Tampa Graduate Theses and Dissertations

Global warming is increasingly obvious, and the reduction of greenhouse gases is an effective way to heal. Increasing the efficiency of catalysts that is applied in the industry can significantly reduce the emission of greenhouse gases. Reverse water gas shift chemical looping (RWGS-CL) is a promising reaction to convert CO2 to CO. La0.5Ba0.5FeO3 (LBF) is a good candidate for RWGS-CL, which shows increased conversion yield when supported on silica. This research focuses on identifying the mechanism of RWGS-CL via silica-supported LBF by exploring the oxygen vacancy formation energy (EO-vac). Density Functional Theory (DFT) is a powerful computational method to solve …

New Developments In Statistical Optimal Designs For Physical And Computer Experiments, Damola M. Akinlana

USF Tampa Graduate Theses and Dissertations

Statistical design of experiments allows for multiple factors influencing a process to be systematically manipulated in an experiment, and their effects on the output of the process to be studied via statistical modeling and analysis. Classical designs offer general nice performance but have limited applications due to restricted design size, region, and randomization structure. Computer generated optimal designs become more popular in recent decades due to the rapid growth in computing power. Most existing work in optimal design of experiments involves designing experiments with optimal performance on a single chosen objective or a single response. However, with the increasing limitation …

A Technique-Based Approach To Structure-From-Motion: Applications To Human-Coastal Environments, Robert Van Alphen

USF Tampa Graduate Theses and Dissertations

Photogrammetry is a method by which physical information can be extracted from thecorrespondence of 2-dimensional images. In the geosciences, Structure-from-Motion (SfM) photogrammetry is a technique that has seen considerable interest in the past decade of research. Here I present three case studies of various scope and methodologies which can inform the use of SfM in the geosciences. First, I discuss the theoretical and algorithmic basis of SfM photogrammetry and its uses thus far in the geosciences. Chapters two through four show specific studies which highlight several approaches to SfM and the data which can be produced. Chapter five then concludes …

Chronological Accumulation Of Microplastics In The Gulf Of Mexico And Their Acute Effects On Coral Bleaching, Martina M. Plafcan

USF Tampa Graduate Theses and Dissertations

Microplastics have accumulated in the environment since plastic production began. They have spread to all areas of the globe from marine trenches to mountains and they can be harmful to organisms. However, research on microplastics has only recently begun so it is unclear how they have changed over time in many regions of the ocean and how current oceanic concentrations might affect marine life. Additionally, organisms such as corals are under stress and have been declining due to climate change, so it is not yet known if microplastics exacerbate these threats. My thesis addressed these gaps in the literature by …

Determining Depth Of Closure Based On Time-Series Beach Profiles And Empirical Formulas: A Case Study Along The Florida Coast, Elizabeth Royer

USF Tampa Graduate Theses and Dissertations

Depth of closure (DOC) is defined as the most landward depth seaward of which there is no significant change in bed elevation and no significant net sediment exchange between the nearshore and the offshore over a certain period of time, such as 5 to 20 years. DOC is an essential parameter used in beach and shore protection, sediment management, and many other aspects of coastal studies. Taking advantage of advancements in wave hindcast and bathymetry measurement in the past 20 years (2000-2019), this study determined the DOC at 12 locations along the Florida coast, including three from the northwest Gulf …

On Simultaneous Similarity Of D-Tuples Of Commuting Square Matrices, Corey Connelly

USF Tampa Graduate Theses and Dissertations

It has been shown by B. Shekhtman that when any d-tuple A of pairwise commuting N × N matrices with complex entries is cyclic, then A is simultaneously similar to the d-tuple of commuting N × N matrices B if and only if B is cyclic, and the sets of polynomials in d variables which annihilate A and B are equivalent.

This thesis offers a further generalization of this result, demonstrating the necessary and sufficient conditions for the simultaneous similarity of n-cyclic d-tuples of commuting square complex-valued matrices.

Securing Critical Cyber Infrastructures And Functionalities Via Machine Learning Empowered Strategies, Tao Hou

USF Tampa Graduate Theses and Dissertations

Machine learning plays a vital role in understanding threats, vulnerabilities, and security policies. In this dissertation, two machine learning empowered approaches on improving the security of critical cyber infrastructures and functionalities will be discussed.

The first work focuses on preventing attacks that use adversarial, active end-to-end topology inference to obtain the topology information of a target network. The topology of a network is fundamental for building network infrastructure functionalities. In many scenarios, enterprise networks may have no desire to disclose their topology information. To this end, we propose a Proactive Topology Obfuscation (ProTO) system that adopts a detect-then-obfuscate framework: (i) …

Metabolomic Analysis, Identification And Antimicrobial Assay Of Two Mangrove Endophytes, Stephen Thompson

USF Tampa Graduate Theses and Dissertations

Natural products have played major roles in drug discovery and provided sources for many new drugs. Secondary metabolites, also called natural products, are organic compounds that are produced from fungi, bacteria, and other living organisms. Secondary metabolites produced by endophytic fungi include alkaloids, phenols, peptides, enzymes, polyketides, and terpenes. Endophytic fungi are rich sources of secondary metabolites and demonstrate bioactivity against many human pathogens including the ESKAPE pathogens. This thesis explores the diverse roles of endophytic fungi and their production of unique secondary metabolites for potential drug discovery and development. Secondary metabolites from two endophytic fungi (EG10-21E-2-HDAC & TAP14-34A-2-HDAC), collected …

Video Anomaly Detection: Practical Challenges For Learning Algorithms, Keval Doshi

USF Tampa Graduate Theses and Dissertations

Anomaly detection in surveillance videos is attracting an increasing amount of attention. Despite the competitive performance of several existing methods, they lack theoretical performance analysis, particularly due to the complex deep neural network architectures used in decision making. Additionally, real-time decision making is an important but mostly neglected factor in this domain. Much of the existing methods that claim to be online, depend on batch or offline processing in practice. Furthermore, several critical tasks such as continual learning, model interpretability and cross-domain adaptability are completely neglected in existing works. Motivated by these research gaps, in this dissertation we discuss our …

Synthesis And Antibacterial Testing Of Novel Thiosulfonate Compounds, Lindsay I. Blume

USF Tampa Graduate Theses and Dissertations

Methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Staphylococcus aureus (VRSA) are increasing concerns in the medical community. In addition to the threat of Staphylococcus aureus, the increase in number and severity of infections caused by other antibiotic-resistant bacteria is problematic to human health, particularly among the ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter). The antibiotics like the penicillins and cephalosporins used commonly to treat MRSA, VRSA, and ESKAPE pathogens have continued to decline in the effectiveness. Our laboratory has developed a number of new families of anti-MRSA and anti-VRSA antibacterial compounds. In this thesis, …

Integration Of Sustainability Into Higher Education Policies: A Case Study Of The University Of South Florida, Mehmet Z. Apaydin

USF Tampa Graduate Theses and Dissertations

Sustainability and the United Nations Sustainable Development Goals (SDGs) are not new notions for higher education institutions (HEIs). However, well-organized efforts to make campuses "sustainable" are not common, and the efforts are modest compared to the institutional capabilities. This thesis, a case study of the University of South Florida (USF), was designed to explore how sustainability values and SDGs are incorporated into higher education policies. To accomplish this, the study employed a mixed method design that includes a literature review, an overview of policies and implementations, document content analysis, a program and course inventory, a keyword analysis, and semi-structured interviews. …

Determinations Of Chemical Equilibria In Natural Waters Using Spectrophotometric Techniques, Katelyn M. Schockman

USF Tampa Graduate Theses and Dissertations

Accurate characterizations of chemical equilibria and thermodynamic processes in natural waters are key components for assessing the current state of our global climate and predicting future changes, especially for observations of small rates of change over long time scales. One of the most important chemical systems in natural waters is the system of inorganic carbon species comprised of carbon dioxide (CO2), bicarbonate, and carbonate. The bicarbonate dissociation constant, K2, describes the relationship between pH and the relative concentrations of bicarbonate and carbonate ions at thermodynamic equilibrium. The carbonate/bicarbonate equilibrium quotient is required in nearly all CO2 system calculations relevant to …

Data-Driven Design And Analysis Of Next Generation Mobile Networks For Anomaly Detection And Signal Classification With Fast, Robust And Light Machine Learning, Muhammed Furkan Küçük

USF Tampa Graduate Theses and Dissertations

This research focuses on machine (and deep) learning applications (including clustering,anomaly detection and signal classification) for self-organizing and next generation mobile networks in wireless communications. Specifically, this dissertation document will address the three different topics.

First, in the study titled “Performance analysis of neural network topologies and hyperparameters for deep clustering”, we explore the relationship between the clustering performance and network complexity. Deep learning found its initial footing in supervised applications such as image and voice recognition successes of which were followed by deep generative models across similar domains. In recent years, researchers have proposed creative learning representations to utilize …

Stability Analysis Of Delay-Driven Coupled Cantilevers Using The Lambert W-Function, Daniel Siebel-Cortopassi

USF Tampa Graduate Theses and Dissertations

A coupled delay-feedback system of two cantilevers can yield greater sensitivity than that of asingle cantilever system, with potential applications in atomic force microscopy. The Lambert W-function analysis concept for delay differential equations is used to more accurately model the behavior of specific configurations of these cantilever systems. We also use this analysis concept to find parameters which yield stability for greater parameter ranges, of the delay differential equations. The Q factor, or quality factor, is the ratio of energy stored in the system, to the energy lost per fixed oscillation/movement cycle. Having stability of the cantilevers corresponds to the …

A Functional Optimization Approach To Stochastic Process Sampling, Ryan Matthew Thurman

USF Tampa Graduate Theses and Dissertations

The goal of the current research project is the formulation of a method for the estimation and modeling of additive stochastic processes with both linear- and cycle-type trend components as well as a relatively robust noise component in the form of Levy processes. Most of the research in stochastic processes tends to focus on cases where the process is stationary, a condition that cannot be assumed for the model above due to the presence of the cyclical sub-component in the overall additive process. As such, we outline a number of relevant theoretical and applied topics, such as stochastic processes and …

Isotopic Study Of The Waters From The Sulphur Springs Catchment, Tampa, Florida, Esra Zengin

USF Tampa Graduate Theses and Dissertations

A stable isotope study was carried out using precipitation, spring water, groundwater well sample, and a seawater sample during the wet season in the Sulphur Springs watershed in Tampa, Florida. Studies that track long term isotopic variation over wet seasons are limited in the region. To fill this knowledge gap, this study aims to quantify the contributions of precipitation and diffuse sources to discharge in Sulphur Springs. A three-component mixing model was applied using δ18O and δ2H values to determine different source water contributions to spring water discharge. The three-component mixing model calculations suggest spring water consists mainly of diffuse …

An Investigation Into The Protein Dynamics And Proton Transfer Mechanism Of Class-A Β-Lactamase (Ctx-Ms) By Nmr Spectroscopy, Radwan Ebna Noor

USF Tampa Graduate Theses and Dissertations

Extended-spectrum β-lactamases (ESBLs) of different Enterobacteriaceae (e.g. Escherichia coli, Klebsiella pneumoniae) have developed significant resistance mechanisms against antibiotics. ESBLs, like class A CTX-Ms (cefotaximases) enzymes hydrolyze the β-lactam ring of different antibiotics such as penicillins and third-generation oxyimino-cephalosporins. Although CTX-Ms are repeatedly found in many clinical and community settings, molecular-level information on their function/activity is currently limited to structural studies performed by X-ray crystallography. In order to gain further insights into the structure and functions of this class of proteins, it is also essential to fully understand their dynamic and chemical properties in solution. In order to better understand the …

Measuring Sustainable Development Through Tax Increment Financed Brownfield Redevelopment Statutes: A Florida Case Study, Jeff Burton

USF Tampa Graduate Theses and Dissertations

This research measures the theoretically sustainable development synergy of United States’ redevelopment, tax increment, and brownfield statutes and questions local redevelopment professionals on this combination’s implementation. This policy’s integration and application measurements guide increased knowledge and best practice methods in the path of America’s population migration into urbanized areas, thus managing the economic, environmental, and social impacts for future generations.

This examination used a pragmatic, qualitative, and quantitative mixed-method approach to identify, collect, code, and analyze redevelopment, tax increment, and state brownfields laws. An exhaustive literature review of the laws’ histories explained when and why they exist. In addition, a …

Desertification Risk Analysis For Wildlife In The Desert Renewable Energy Conversation Plan Area Of California, Serdar Sagdic

USF Tampa Graduate Theses and Dissertations

Desertification is one of the primary threats facing the sustainability of the Earths’s natural resources. Desertification it is an outcome of human impacts to ecosystems and alterations of climate patterns resulting in land degradation and adverse effect on natural resources, vegetation loss, soil infertility, and water scarcity. These changes influence the existence and distribution of wildlife by reducing the availability and quality of habitat that provides food, water, cover, and other life requisites. Therefore, this study aimed at evaluation of potential desertification risks on wildlife species in the Desert Renewable Energy and Conservation Plan (DRECP) area of California.

The DRECP …

Bioactivity Of Suberitenones A And B, Jared G. Waters

USF Tampa Graduate Theses and Dissertations

Throughout human history, natural products have formed the foundation of medicine. In ancient times, a myriad of herbs and fungi have been attributed properties of healing and rejuvenation. Today, that foundation still very much exists, as natural product chemists isolate bioactive compounds from plants, fungi, animals, and microorganisms alike. As more of these secondary metabolites are discovered, scientists pursue more and more sources of biodiversity that may yield new and unprecedented compounds. To this end, Antarctica has become of particular note, as its unique environmental conditions and highly isolated nature make for rare and unusual adaptations in its native wildlife. …

Advances And Applications Of Optimal Polynomial Approximants, Raymond Centner

USF Tampa Graduate Theses and Dissertations

The history of optimal polynomial approximants (OPAs) dates back to the engineering literature of the 1970s. Here, these polynomials were studied in the context of the Hardy space H^2(X), where X denotes the open unit disk D or the bidisk D^2. Under certain conditions, it was thought that these polynomials had all of their zeros outside the closure of X. Hence, it was suggested that these polynomials could be used to design a stable digital filter. In recent mathematics literature, OPAs have been studied in many different function spaces. In these settings, numerous papers have been devoted to studying the …

Block Copolymer Directed Self-Assembly: Exploring The Efficacy Of Applications In Semiconductor Fabrication, Jakin Bryce Delony

USF Tampa Graduate Theses and Dissertations

Over the course of the past 80 years, semiconductor devices have become increasingly ubiquitous in everyday life.From constructing mainframes that encompassed entire rooms during the 1940s, to inventing personal computers in the 1980s, to developing progressively faster smartphones and wearable technology in the 2010s, the primary driving force behind the Digital Revolution has been increasing transistor counts, and thus computing power, via incremental improvements in optical lithography. In 1965, Intel co-founder Gordon Moore boldly predicted that the transistor density of semiconductor devices would double approximately every 18-24 months. While this prediction -- now colloquially referred to as Moore's Law -- …

Relationships Among The Community Of Inquiry, Achievement Emotions, And Academic Achievement In Asynchronous Online Learning In Higher Education, David H. Tai

USF Tampa Graduate Theses and Dissertations

This research aimed to investigate how achievement emotions predict, mediate, and affect academic achievement in online learning. Online learning has been proliferating, but little is known about how emotion mediates cognition in the Community of Inquiry framework. Recent progress in cognitive neuroscience provided the theoretical foundation for researchers to investigate emotion's role in online learning, especially academic achievement. The researcher of this study adopted a quantitative non-experimental research design to investigate how achievement emotions mediated, predicted, and affected academic achievement in the Community of Inquiry framework. The Partial Least Square Structure Equation Modeling (PLS- SEM) method was adopted for statistical …