Digital Commons Network^™

Advances In Model Reference Adaptive Control: Exploring Gain Scheduling, Scalability, And Time-Varying Command Following, Jesse Jaramillo

USF Tampa Graduate Theses and Dissertations

Feedback control architectures are fundamental for achieving a desired response in physical systems. A robust and reliable design must account for system uncertainties and exogenous disturbances, which may arise from phenomena such as modeling approximations, nonlinearities, degraded modes of operations, wind gusts, or structural impairments. Two widely recognized methods to mitigate the negative impact of uncertainties and disturbances are robust and adaptive control architectures. Specifically, robust control designs ensure stability by considering a worst-case scenario, which can potentially lead to suboptimal performance or steady-state errors depending on the nature of the uncertainty. In contrast, adaptive control designs offer the capability …

From Graph Theory For Robust Deep Networks To Graph Learning For Multimodal Cancer Analysis, Asim Waqas

USF Tampa Graduate Theses and Dissertations

This dissertation explores the intersection of graph theory and deep learning, focusing on enhancing the robustness of deep neural networks (DNNs) and applying these advancements to complex problems like cancer diagnosis and treatment. We investigate the structural properties of graphs and their influence on neural network performance, particularly in multimodal learning. The work delves into the design space of DNN architectures using graph-theoretic measures, transforming graphs into DNN architectures for various tasks, and examining their robustness against noise and adversarial attacks. The study extends to medical imaging, highlighting advanced DNN architectures like U-Net for brain tumor segmentation. It addresses the …

Investigation Of The Use Of Recycled Concrete Aggregates In Porous Asphalt Mixture, Asad Elmagarhe

USF Tampa Graduate Theses and Dissertations

This study aims to address the national need for using recycled concrete in road pavements. This is especially important in the governmental and corporate sectors, where reducing the cost and carbon footprint of construction projects is a priority. The long-term goal is to meet the public demand for environmentally friendly infrastructure and minimize the harmful effects of waste disposal on humans and the environment.

The project focuses on using recycled concrete aggregate (RCA) in porous asphalt pavement to reduce stormwater runoff, a popular environmentally friendly road design. However, compared to regular dense asphalt mixtures, porous asphalt mixtures (PAM) are more …

Optimizing Cybersecurity Operations Using Data-Driven Intelligence, Jalal Ghadermazi

USF Tampa Graduate Theses and Dissertations

Cybersecurity operations centers (CSOCs) play a crucial role in safeguarding organizations from cyber threats. CSOC operations are divided into two main areas: Intrusion detection systems (IDS) and security response team (SRT) operations. Machine learning (ML) and deep learning (DL) advancements have significantly improved IDSs. IDS can be either flow-based, suitable for offline analysis, or packet-based, which analyze traffic in real-time. However, packet-based IDS often treat packets independently, ignoring the sequential nature of network communication. Additionally, recent ML/DL approaches also struggle with capturing global and structural information and novel attack detection due to their reliance on labeled data. The SRT within …

Transforming Organizational Cyber Security With Artificial Intelligence And Data-Driven Optimization, Soumyadeep Hore

USF Tampa Graduate Theses and Dissertations

This dissertation presents a comprehensive framework for enhancing organizational cybersecurity through data-driven intelligence. The research integrates multiple methodologies to tackle challenges in network intrusion detection and vulnerability management within cybersecurity operations centers (CSOCs). First, the research investigates vulnerability prioritization and mitigation techniques currently employed by CSOCs. To further streamline the vulnerability prioritization and mitigation process a machine learning (ML)-based Vulnerability Priority Scoring System (VPSS) is introduced, significantly improving the prioritization and mitigation of context-sensitive vulnerabilities. The VPSS outperforms traditional methods, reducing the cumulative vulnerability exposure score by up to 30% by considering both organizational context and vulnerability severity. Next, the …

Gender Role Depictions In Arabic Children’S Picture Books, Aljawharah A. Almuqbil

USF Tampa Graduate Theses and Dissertations

This study aimed to explore gender role depictions in children's Arabic picture books. The importance of this study emerged from its focus on young children, where the concept of gender begins to be constructed. This study provided insight into the nature of gender roles in children’s picture books, especially under the remarkable changes that Saudi society is witnessing and the lack of Arab studies in this area. Social cognitive theory, gender schema theory, and critical literacy pedagogy guided the study. A sample of 26 picture books was selected from the Child Book Club at King Abdulaziz Public Library and analyzed …

Mathematical Modeling Of Tumor Response Dynamics To Predict Progression-Free Survival In Patients With Recurrent High-Grade Glioma, Daniel James Glazar

USF Tampa Graduate Theses and Dissertations

In this dissertation, I aim to develop a mathematical model describing tumor volume response dynamics to perform individual dynamic predictions of progression-free survival (PFS) on patients with recurrent high-grade glioma (rHGG).

Patients with rHGG have a dismal prognosis with median overall survival (OS) of <12 months and median PFS of <7 months. However, there is a wide heterogeneity in treatment responses. Therefore, to aid clinicians with making decisions to alter therapeutic protocol, I would like to predict patient-specific PFS.

To perform individual dynamic predictions, I employ the Claret tumor growth inhibition (TGI) model. I further develop this model by coupling it with two different survival models. Inter-patient heterogeneity is also taken into account through mixed effects, including covariate effects. Model PFS predictions were evaluated using receiver operating characteristic (ROC) curve analysis as well as Brier …

Stochastic Analytical Predictive Models For Life Sciences And Crop Production Process, Erasmus Tetteh-Bator

USF Tampa Graduate Theses and Dissertations

Analytical predictive modeling uses algorithm-based mathematical, probabilistic and statistical methods to anticipate future events by identifying patterns in past data. It is a technique for predicting outcomes and a key application of statistical analysis in real-world scenarios. Real data-driven predictive models in various fields, such as life sciences, economics,or production industry, help individuals and institutions make data-driven informed decisions, which is essential for business success, providing companies with a competitive edge.

One of every five adult deaths is caused by heart disease and one person dies every 33 from cardiovascular disease in the United States according to the Center for …

A Robust Data-Driven Framework For Artificial Intelligent Systems, Quoc H. Nguyen

USF Tampa Graduate Theses and Dissertations

Artificial Intelligence (AI) systems have demonstrated remarkable performance across various domains. However, their robustness remains a critical concern, particularly in terms of data and model reliability. This dissertation aims to address the challenges associated with building robust AI systems by focusing on two key aspects: data robustness and model robustness. Data robustness poses significant challenges, including data shift, concept shifting, limited and imbalanced datasets, and interoperability issues in IoT systems for data collection. Existing methods fall short in handling dynamic business objectives and evolving data landscapes effectively. To bridge these gaps, we propose an IoT framework that ensures interoperability, seamless …

Black Holes In Time: The Effect Of Grid Radiation On The Tumor Immune Microenvironment, Rebecca A. Bekker

USF Tampa Graduate Theses and Dissertations

Tumor-immune interactions shape a developing tumor and its tumor immune microenvironment (TIME) resulting in either well-infiltrated, immunologically inflamed ‘hot’ tumor beds, or ‘cold’ immune deserts with low levels of infiltration. The pre-treatment immune state of the TIME is associated with treatment outcome; immunologically hot tumors generally exhibit better responses to radio- and immunotherapy than cold tumors. However, radiotherapy is known to induce opposing immunological consequences, resulting in both immunostimulatory and inhibitory responses. In fact, it is thought that the radiation induced tumoricidal immune response is curtailed by subsequent applications of radiation. Thus, I hypothesize that spatially fractionated radiotherapy (SFRT), administered …

Model-Based Systems Engineering For Engineering Education Systems Simulation, Pallavi Singh

USF Tampa Graduate Theses and Dissertations

As the engineering education system continuously evolves to meet the demands of modern industry and society, there is a need for a methodology that would manage and resolve the complexities inherent in engineering educational systems. Model-based Systems Engineering (MBSE) is a structured approach to system design that utilizes models across all stages of the system's life cycle and supports requirements management, design, analysis, verification, and validation processes. While MBSE has been applied successfully in industries like defense, aerospace, and automotive, its application in engineering educational systems remains unexplored. This dissertation develops a dynamic model of the university-level engineering education system …

Modeling The Development Of Borderline Personality Disorder: A Formal Theory Approach, Alexandria M. Choate

USF Tampa Graduate Theses and Dissertations

Borderline personality disorder (BPD) is a complex disorder characterized by instabilities in emotion regulation, impulse control, and interpersonal relationships. BPD affects adolescent and adult populations at similar rates, with traits often detectable in late childhood or early adolescence. Despite some progress in the understanding of BPD and its development, contemporary theories have yet to address several important questions in the literature. The present study suggests that many limitations associated with current theoretical models of BPD may be attributable to an overdependence on verbally specified, or weak theories. In most cases, weak theories are constructed using vague or imprecisely defined hypotheses …

Anonymized Identity Recognition And Classification Using Privacy Preserving Facial Encoding, Manas Sanjay Pakalapati

USF Tampa Graduate Theses and Dissertations

The need for sharing large-scale datasets to train deep neural network models, particularly in healthcare, raises significant data security and privacy concerns. To address these issues, methods such as data encryption or encoding are utilized. These techniques can encrypt the data and make it unreadable to humans, while still retaining its usefulness for training models.

In this study, we investigate various image encoding techniques designed to protect privacy by making images unrecognizable while still retaining their usefulness for model training. Our investigation utilized publicly available facial databases and focused on evaluating the trade-offs inherent in image encoding techniques, with a …

Optimal Selection Of Good Polynomials And Constructions Of Locally Recoverable Codes Via Galois Theory, Austin Dukes

USF Tampa Graduate Theses and Dissertations

To keep up with the ever-growing demand for reliable and efficient availability of data,locally recoverable codes (LRCs) have been the focus of much study due to their applications in cloud and distributed storage systems. A fundamental construction of LRCs was given in [36] based on polynomials which relied on the existence of r-good polynomials. In the same paper some constructions of good polynomials were given, but these constructions did not cover every configuration of parameters. Naturally this led to research into constructing good polynomials for what was not addressed in [36], but new ponderings were also posed, such as the …

Painting A New Perspective On Ordovician Echinoderm Diversity Patterns, Ohav Barak Harris

USF Tampa Graduate Theses and Dissertations

The Ordovician Period was a time of great biotic and environmental change, encompassing two important biotic events: the Great Ordovician Biodiversification Event (GOBE) and the Late Ordovician Mass Extinction (LOME). The GOBE occurred during the Middle Ordovician and was a period of rapid diversity increase for marine invertebrate groups, as lower-level taxonomic groups like families and genera came into the forefront. The Ordovician ends with the LOME, an extinction event that is thought to have occurred in two phases: an initial glaciation followed by a subsequent warming. Approximately 85% of marine species went extinct during the LOME, making it the …

An Analysis Of (Hu)Manid Using The Usf Donated Skeletal Collection: Estimating Sex And Ancestry For Edentulous Individuals, Natalie S. Wise

USF Tampa Graduate Theses and Dissertations

The Human Mandible Identification program, (hu)MANid©, enables anthropologists to estimate the sex and ancestry of unidentified skeletal remains from metric and morphoscopic variables from the mandible. The program is suitable for a variety of anthropological contexts, including forensic casework and bioarchaeological or paleoanthropological analyses. The purpose of this research project is to test the accuracy and applicability of the (hu)MANid program on edentulous mandibles. While the authors of (hu)MANid warn against data collection for edentulous mandibles, there are many circumstances in applied forensic casework where the unidentified person is edentulous. Edentulous individuals experience alveolar resorption, which is the loss of …

Aligning Clinical Productivity Of Cancer Care Providers: A Simulation-Based Approach, Maile Sinclair-Baxter

USF Tampa Graduate Theses and Dissertations

The growing number of cancer patients over the years has presented many challenges and opportunities for improvement in the healthcare system. These challenges and opportunities have demonstrated the need for a tool that can enhance the clinical productivity of healthcare providers, ultimately impacting patients’ overall experience. We studied the clinical Full Time Equivalency (cFTE) for providers at a cancer research center. cFTE is the percentage of time allocated for clinical work. In this cancer research center, the clinical work of each provider is supposed to match a targeted cFTE. The cancer research center’s concern was that the provider’s clinical productivity …

Using Brain Break® In The Classroom To Increase On-Task Behavior And Decrease Disruptive Behaviors Of Students, Michaela C. Elza

USF Tampa Graduate Theses and Dissertations

Off-task and disruptive behavior are one of the greatest causes to loss of instructional time in the classroom. Teachers spend time addressing student challenging behaviors which consequently cuts time from their academic instruction. Antecedent exercise programs, such as Brain Breaks®, provide teachers with short physical activity videos that provide students a movement break between long periods of academics without the need for expensive equipment. This study evaluated the effects of Brain Breaks® videos to increase students’ on-task and decrease disruptive behaviors in the classroom. Three participants were included in this study, Jordan a 6-year-old male, Andrew an 8-year-old male, and …

Advancing Adversarial Audio: Human-In-The-Loop Black-Box Attacks, Rui Duan

USF Tampa Graduate Theses and Dissertations

Adversarial audio attacks pose significant security challenges to real-world audio applications. Attackers may manipulate speech to impersonate a speaker, gaining access to smart devices like Amazon Echo. In audio applications, there are two key areas: music and speech. In music, most attackers create a small noise-like perturbation on the original signal to evade copyright detection. However, this method degrades music's perceived quality for human listeners. In the speech, creating an adversarial example often requires many queries to the target model, a process too cumbersome for practical use in real-world scenarios, like interacting with smart devices numerous times.

In this dissertation, …

Trajectories Of Well-Being: Results From The Americans’ Changing Lives Study, Cassondra M. Lyman

USF Tampa Graduate Theses and Dissertations

There is considerable interest in elucidating the dynamics of well-being over long periods of time, including how well-being dynamics are influenced by depression. The Americans' Changing Lives (ACL) study has followed the health and well-being of a nationally representative sample of adults in the United States for 25 years (N1986 = 3,617; N1989 = 2,867; N1994 = 2,562; N2002 = 1,787, N2012 = 1,427). Leveraging data from the ACL study, the present investigation employed growth mixture models to identify unobserved subpopulations (i.e., latent classes) typified by change in well-being over time. Three predominant trajectories for well-being were identified: relative stability …

Improving Academic Engagement And Task Completion Using Antecedent Physical Exercise In An Elementary School Classroom, Grace N. Maxwell

USF Tampa Graduate Theses and Dissertations

This study investigated the effectiveness of antecedent physical activity interventions in enhancing academic engagement and task completion among first-grade students displaying off-task behaviors. The research involved three student participants from a first grade general education classroom. An ABAB reversal design was used to assess the impact of the intervention. The intervention, implemented by the classroom teacher, consisted of short, structured physical activities conducted before targeted academic periods. Results revealed significant improvements in both academic engagement and task completion following the implementation of the physical activity interventions. The findings suggest that incorporating brief physical activities into daily classroom routines can lead …

Unveiling Ferroelectric And Multifunctional Insights In Hybrid Formate Perovskites, Abduljelili Popoola

USF Tampa Graduate Theses and Dissertations

Formate perovskites, denoted as AB(HCOO)3, represent a diverse group of hybrid organic-inorganic compounds, renowned for their numerous phase transitions and a wide array of properties. These properties encompass (anti)ferroelectricity, ferroelasticity, (anti)ferromagnetism, and multiferroism. Despite extensive research on these materials, a comprehensive examination of their properties across a substantial number of formate perovskites remains scarce. This scarcity stems from structural complexity of these materials, potential systematic errors arising from different measurement techniques or incomplete data. For instance, data for critical parameters like piezoelectricity, dielectricity, and elasticity tensors have been lacking.

In this study, we address these challenges by employing first-principles density …

Specification, Enforcement, And Measurement Of Integrity Policies, Kevin Dennis

USF Tampa Graduate Theses and Dissertations

The first step to improving an organization's security posture is to define the organization's security goals. At a technical level, these goals are expressed as security policies. Security policies are predicates over programs, that return true or false if the program adheres to the policy. Defining these policies correctly is thus essential to ensuring the overarching security goals are met, but it is often quite difficult to translate human-oriented goals into their technical policy counterparts. In addition, these policies must be specified so that they are enforceable while minimizing false positives and false negatives. Integrity policies, which specify how data …

Investigating The Impact Of Inverter-Based Resources On Power Grid Dynamics, Ratik Mittal

USF Tampa Graduate Theses and Dissertations

This dissertation explores the stability challenges posed by integrating Inverter-Based Resources (IBR) into power grids, particularly focusing on two major scenarios: IBRs connected to weak grid interconnections and their performance in series-compensated networks. With the increasing dependency on renewable energy sources, ensuring the stability of these grids is crucial. A multilayered investigative approach is employed, utilizing Electromagnetic Transient Simulations that model grid systems interfaced with IBRs. These simulations are pivotal as they emulate real-world stability issues and provide a foundational understanding of grid interactions. In this dissertation two major types of IBR control are modeled and analyzed: Grid Following Control …

Exploring The Enlightenment Function Of Thought Experiments: Unveiling An Underdeveloped Dimension Absent In Typologies, Dominique Greene-Sanders

USF Tampa Graduate Theses and Dissertations

Thought experiments (TEs) are imaginative tools used across various fields to explore theoretical and practical issues. This dissertation focuses on the application of TEs in ethics, specifically emphasizing the underdeveloped enlightenment function. The traditional use of TEs in ethics often aims to clarify, support, or refute specific claims through an argumentative structure. However, this work argues that TEs also play a key role in enhancing ethical competence by acknowledging the complexities of ethical dilemmas and fostering moral skills like critical thinking, moral reasoning, and ethical awareness through non-argumentative and non-theory-centric means.

The dissertation begins by explaining the nature and historical …

Evaluation Of Reduced Graphene Oxide For Advanced Thermal Management In Microwave Electronics Packaging, Utkarsh Misra

USF Tampa Graduate Theses and Dissertations

The continuous push towards making electronic devices smaller and denser, largely driven by the demand for higher power capabilities, has led to a critical need for innovative and comprehensive methods for managing the heat these devices generate. Traditional cooling solutions for electronics often rely on methods such as copper-based layers or channels to distribute and dispel heat. However, these conventional methods and materials are becoming increasingly insufficient, especially for Radio Frequency (RF) and millimeter-wave electronics. These components are becoming ever more compact while requiring more power, thus presenting unique challenges for thermal management in their packaging.

In this thesis we …

High-Performance Computing In Next-Generation Sequencing Read Alignment, Minh H. Pham

USF Tampa Graduate Theses and Dissertations

Advancements in Next-Generation Sequencing (NGS) have dramatically reduced the cost and increased the speed of DNA sequencing. However, this rapid influx of data necessitates efficient and robust analysis tools, particularly for the complex task of aligning short NGS reads to reference genomes such as the human genome. We explore groundbreaking computational strategies and hardware acceleration to optimize this critical alignment process. This dissertation is structured around three innovative studies. First, we introduce a novel approach to dynamic memory allocation tailored for massively parallel systems, particularly Graphical Processing Units (GPUs), to support NGS alignment and other applications. Unlike traditional memory allocators …

Quantification And Diversity Of A Ubiquitous Ssdna Phage Group (Gokushovirinae) In The Red Sea Through The Polony Technique, Natalie A. Sawaya

USF Tampa Graduate Theses and Dissertations

With average concentrations of 107 virus-like particles per milliliter of seawater, viruses comprise the second largest biomass in the ocean, where they are a driving force of microbial evolution and constitute important roles in Earth’s biogeochemical cycles. Bacteriophage (phage), viruses that infect bacteria, are of particular importance in the marine ecosystem as they impact the efficiency of the microbial loop, which recycles carbon in surface waters, counteracting vertical export through the biological pump. Although double-stranded DNA phage have been researched extensively, single-stranded DNA (ssDNA) phage remain understudied, mostly due to methodological limitations.

The incorporation of rolling circle amplification (RCA) into …

The Polyaneuploid Cancer Cell State And Therapeutic Resistance: Eco-Evolutionary Dynamics In Structured Populations, Anuraag Bukkuri

USF Tampa Graduate Theses and Dissertations

In this dissertation, I develop and apply eco-evolutionary modeling techniques to understand how the polyaneuploid cancer cell (PACC) state, entered when aneuploid cells exit the cell cycle after S phase and undergo a whole genome duplication, contributes to therapeutic resistance. Since resistance remains one of the primary causes of treatment failure in cancer patients, it is critical to understand how such demographic state transitions allow for acclimatization of cancer cells to therapeutic stressors and how they interact with evolutionary processes to promote irreversible resistance.

In Chapters Two and Three, I lay the foundation for this work. In Chapter Two, I …

Subtropical Estuarine Ecosystems Display Both Long-Term Stability And Change, Garrett L. Miller

USF Tampa Graduate Theses and Dissertations

Subtropical estuaries often support abundant and diverse faunal assemblages, but it is unclear how these productive ecosystems are responding to climate change. In the eastern Gulf of Mexico, estuarine faunal assemblages have been sampled for decades as part of a fisheries-independent long-term monitoring program. I assessed trends in submerged aquatic vegetation, water temperature, and the abundance, richness, and structure of faunal assemblages over more than two decades in four estuarine systems using this dataset. I used both univariate and multivariate analyses to quantify and describe the dynamics of these habitat and faunal variables. Further, I separated my analyses for summer …