Physical Sciences and Mathematics Commons^™

Soil Characteristics Associated With Horse Cases Of Eastern Equine Encephalitis Virus In Florida, Fulya Guzelkucuk

USF Tampa Graduate Theses and Dissertations

Eastern Equine Encephalitis virus (EEEV) is a mosquito-borne virus found in Florida that affects humans and horses. Also, EEEV is an agricultural land management issue in Florida, as it causes mortality in large numbers of horses each year and sometimes humans. This study investigates the characteristics of soils associated with horse cases of EEEV in the State of Florida, focusing on differences in soil characteristics between summer and winter cases. This study analyzed a total of 676 EEEV cases during 2005-2018, including 611 summer cases and 65 winter cases. Soil characteristics that were examined include: soil texture, drainage class, hydrology …

Geophysical And Social Influences On Evacuation Decision-Making: The Case Of Hurricane Irma, Robin Ersing, Christianne Pearce, Jennifer M. Collins, Michelle E. Saunders, Amy Polen

School of Geosciences Faculty and Staff Publications

Understanding the factors that influence evacuation decision-making among local residents is of critical importance to those involved in monitoring and managing weather-related hazards. This study examined both geophysical and social variables that we believe influenced individual decision-making on whether to stay home, seek out a public shelter, or leave the area entirely during Hurricane Irma. A 23-item survey was administered to a convenience sample of adults (n = 234) who resided within a coastal Florida county that received an evacuation warning during Hurricane Irma in 2017. Results suggested sources of information relied on through media, government, family, and social networks …

Black Lives Matter In Engineering, Too! An Environmental Justice Approach Towards Equitable Decision-Making For Stormwater Management In African American Communities, Maya Elizabeth Carrasquillo

USF Tampa Graduate Theses and Dissertations

The United States and the world have recently been challenged with the disparate effects of COVID-19 and the continual killings of unarmed Black men and women across the nation. A history of anti-black racism has led to systemic structures of inequity that thread throughout institutions and communities across the nation. This environmental engineering research comes at a time when understanding how to effectively engage in, and with Black communities is at the forefront of discourse in academia, utilities and private sector.

In 2018 the Brookings Institute published a report on workforce in the water sector demonstrating the lack of diversity …

Chemical Investigation Of Floridian Mangrove Endophytes And Antarctic Marine Organisms, Bingjie Yang

USF Tampa Graduate Theses and Dissertations

Nature creates diseases and illnesses for mankind, however, nature also provides therapeutics by making biological systems produce secondary metabolites. Although the secondary metabolites originally play roles in chemical defense or evolution, researchers have been working on them for drug discovery. Plants, fungi and marine organisms have been mostly explored by natural products chemists over the century and contributed most drugs to the market. With the increasing need of new drugs resulting from drug resistance and pathogen evolution, the natural products area has been focused on developing innovative methodologies to achieve higher efficiency of isolating new bioactive compounds.

This dissertation herein …

A Chemical Investigation Of Three Antarctic Tunicates Of The Genus Synoicum, Sofia Kokkaliari

USF Tampa Graduate Theses and Dissertations

Marine invertebrates, mainly sponges, tunicates and corals, have in the past few decades attracted the interest of the scientific community in regard to their secondary metabolites and their potential as leads in drug discovery. The genus Synoicum is comprised of multiple organisms found in both deep and shallow waters, tropical and cold environments around the world. The majority of the members of this genus that have been investigated can be found in shallow tropical waters due to the ease of accessing and collecting them. Of the cold environments, Antarctica is a representative of the environments where members of the Synoicum …

Deep Learning Predictive Modeling With Data Challenges (Small, Big, Or Imbalanced), Renhao Liu

USF Tampa Graduate Theses and Dissertations

In the real world, data used to build machine learning models always has different sizes and characteristics. These size and characteristic features, including small datasets, big datasets, imbalanced datasets, often lead to different challenges when training machine learning models. Models trained on a small number of observations tend to overfit the training data and produce inaccurate results. When it comes to big data, efficiently learning from "huge" size data in a short time becomes important. With an imbalanced dataset, learning is usually biased towards the majority class in the data and appropriate measurements are needed to check model performance.

As …

An Ethnography Of Wash Infrastructures And Governance In Sulphur Springs, Florida, Mathews Jackon Wakhungu

USF Tampa Graduate Theses and Dissertations

This dissertation describes the forces that shape the perceptions and practices in Water, Sanitation, and Hygiene (WaSH) services in the community of Sulphur Springs, Tampa, Florida. It also explores how these forces, perceptions, and practices produce adverse experiences and inequalities in water, sewer, drainage, and laundry services. This ethnographic study combines participant observation, ethnographic interviewing, freelisting, oral history, and GIS to uncover the context, experiences, and perceptions about WaSH in Sulphur Springs. The study finds that the present conditions and perceptions about WaSH are embedded into the historical contexts—especially racial segregation, the construction of the interstate, and multiple economic downturns …

Beyond The Hype: Challenges Of Neural Networks As Applied To Social Networks, Anthony Hernandez

USF Tampa Graduate Theses and Dissertations

Recent advances in neural network-based machine learning algorithms promise a rev-olution in prediction tasks across a variety of domains. Of these, forecasting user activity insocial media is particularly relevant for problems such as modeling and predicting informa-tion diffusion and designing intervention techniques to mitigate disinformation campaigns.Another potential task is anonymizing social network datasets to facilitate their distributionand promote research. Given the success of deep generative models, it may be possible touse them for anonymization. Social media seems an ideal context for applying neural net-work techniques, as they provide large data sets and challenging prediction objectives. Yet,our experiments find a number …

Distributed Control Of Multiagent Systems Under Heterogeneity, Selahattin Burak Sarsilmaz

USF Tampa Graduate Theses and Dissertations

The overarching objective of this work is to propose solutions to quite a few distributed control problems arising from networks of heterogeneous agents or the heterogeneous nature of multiagent systems. Each problem with its solutions is concisely summarized below.

We consider the cooperative output regulation problem of heterogeneous linear multiagent systems over fixed directed communication graphs. The purpose of this problem is to design a distributed control law such that the overall closed-loop stability is ensured and the tracking error of each agent converges to zero asymptotically for a class of reference inputs and disturbances generated by a so-called exosystem. …

A Process-Based Approach To Evaluating The Role Of Organic Ligands In Trace Metal Cycling In The Marine Environment, Travis Mellett

USF Tampa Graduate Theses and Dissertations

In addition to control by major nutrient elements (nitrogen, phosphorous, and silicon) growth and community composition of marine phytoplankton is also regulated by trace element nutrients (iron, copper, manganese, zinc, cobalt, nickel, and cadmium). Of these, iron is the most influential in the modern ocean, regulating phytoplankton growth and carbon export in high-nutrient low-chlorophyll regimes and exerting an important control on the marine nitrogen cycle through its role in di-nitrogen fixation. The distributions of these metals has the capacity to control primary production and phytoplankton community composition through differences in cellular quotas or metal sensitivities amongst species. The relationship between …

The Perceived Usefulness Of A Weather Radar Display By Tampa Bay Residents, Michelle E. Saunders

USF Tampa Graduate Theses and Dissertations

A weather radar display is a tool that provides spatially oriented, timely information about an impending weather event. While radar is frequently used by meteorologists, emergency managers, and pilots, this tool is now readily available for individuals to use on a variety of platforms including television, computer/laptop, smartphones and tablets. Most importantly, there are hundreds of mobile weather applications available as well as online sources that provide a weather radar display. However, little is known about how individuals use a weather radar display. Therefore, the purpose of this dissertation is to understand why radar is sought out as a tool …

Efficient Viewshed Computation Algorithms On Gpus And Cpus, Faisal F. Qarah

USF Tampa Graduate Theses and Dissertations

Nowadays with the advance in managing and collecting large data, GIS is one of the applications that suffer from lack of efficient data management methods. GIS data often come in form of maps with different types of data such as temperature, topology, and population.

This dissertation focuses on exact-viewsheds computation for large terrains, and due to the poor performance of current exact-viewshed algorithms that may need several hours to process a midsize map, we found the need for new algorithms that are capable of efficiently computing viewshed for large size maps. This work presents a highly-efficient exact-viewshed computation algorithm based …

Dynamics And Impacts Of The May 8th, 1902 Pyroclastic Current At Mount Pelée (Martinique): New Insights From Numerical Modeling, Valentin Gueugneau, Karim Kelfoun, Sylvain J. Charbonnier, Aurelie Germa, Guillaume Carazzo

School of Geosciences Faculty and Staff Publications

The Mount Pelée May 8th, 1902 eruption is responsible for the deaths of more than 29,000 people, as well as the nearly-complete destruction of the city of Saint Pierre by a single pyroclastic current, and is, sadly, the deadliest eruption of the 20th century. Despite intensive field studies on the associated deposit, two conflicting interpretations of the pyroclastic current dynamics (either a blast or a simple ash-cloud surge) emerged in the 90’s and have been paralyzing research ever since, leaving numerous unknowns (i.e., source conditions, volume). This study is the first to investigate numerically the May 8th, 1902 pyroclastic …

Socio-Technical Transitions In The Water Sector: Emerging Boundaries For Utility Resilience In Barbados, Wainella N. Isaacs

USF Tampa Graduate Theses and Dissertations

Resilience is gaining popularity in the water sector where it described as contributing to reduced vulnerability to water-related risks and hazards including climate change. Unfortunately, literature in this area, contributed mainly from North America and Europe, is fragmented with a concentration on engineering resilience in water supply infrastructure. The absence of any scholarship on resilience for a small island nation, coupled with the absence of sociological contributors to building resilience in this sector motivated this research.

The goal of this research was to understand and evaluate how resilience is characterized and operationalized in the Barbados water and wastewater infrastructure system, …

Machine Learning For The Internet Of Things: Applications, Implementation, And Security, Vishalini Laguduva Ramnath

USF Tampa Graduate Theses and Dissertations

Artificial intelligence and ubiquitous sensor systems have seen tremendous advances in recent times, resulting in groundbreaking impact across domains such as healthcare, entertainment, and transportation through a collective ecosystem called the Internet of Things. The advent of 5G and improved wireless networks will further accelerate the research and development of tools in deep learning, sensor systems, and computing platforms by providing improved network latency and bandwidth. While tremendous progress has been made in the Internet of Things, current work has largely focused on building robust applications that leverage the data collected through ubiquitous sensor nodes to provide actionable rules and …

Pystprism: Tools For Voxel-Based Space–Time Prisms, Rebecca Loraamm, Joni A. Downs, James Anderson, David S. Lamb

School of Geosciences Faculty and Staff Publications

The observed movements of humans and animals are realizations of complex spatiotemporal processes. Recent advances in location-aware technologies have rendered trajectory data ubiquitous. Examining the sequenced, instantaneous locations found in movement trajectory data for information reconstructing the location or state of the mover between observed points comprises a primary focus in Time Geography and related disciplines. The PySTPrism toolbox introduced in this paper provides a straightforward and open-source implementation of the Probabilistic Space Time Prism, in addition to related tools from Time Geography. PySTPrism is implemented in Python using the ArcPy module in ArcGIS Pro Desktop.

Novel Quantification Of Shallow Sediment Compaction By Gps Interferometric Reflectometry And Implications For Flood Susceptibility, Makan A. Karegar, Kristine M. Larson, Jurgen Kusche, Timothy H. Dixon

School of Geosciences Faculty and Staff Publications

Estimates of flood susceptibility and land loss in the world's coastal regions depend on our knowledge of sea level rise (SLR) from increases in ocean mass and volume, as well as knowledge of vertical land motion. Conventional approaches to the latter include tide‐gauge and Global Positioning System (GPS) measurements relative to well‐anchored monuments few meters below the surface. However, in regions of rapid Holocene sedimentation, compaction of this material can add a significant component to the surface lowering. Unfortunately, this process has been difficult to quantify, especially for the shallowest material above the monument. Here we use a new technique, …

Construction Of Giant 2d And 3d Metallo-Supramolecules Based On Pyrylium Salts Chemistry, Yiming Li

USF Tampa Graduate Theses and Dissertations

Pyrylium salts are a type of six-membered cationic heterocycles with one positively charged oxygen atom. Since the discovery of pyrylium salts in 1911, such salts have been underappreciated for a long time. Until 1960s, the importance of pyrylium salts has been realized as versatile precursors in a variety of organic syntheses. Due to their high reactivity towards various nucleophiles, pyrylium salts were widely used for the convenient synthesis of diverse heterocyclic compounds. Starting from 1980s, the high reactive feature of pyrylium salts were further utilized to synthesize viologen polymers with pyridinium salts in the backbones. During the past two decades, …

Relational Joins On Gpus For In-Memory Database Query Processing, Ran Rui

USF Tampa Graduate Theses and Dissertations

Relational join processing is one of the core functionalities in database management systems. Implementing join algorithms on parallel platforms, especially modern GPUs, has gain a lot of momentum in the past decade. This dissertation addresses the following issues on GPU join algorithms. First, we present empirical evaluations of a state-of-the-art work on GPU-based join processing. Since 2008, the compute capabilities of GPUs have increased following a pace faster than that of the multi-core CPUs. We run a comprehensive set of experiments to study how join operations can benefit from such rapid expansion of GPU capabilities. We also present improved GPU …

Active Deep Learning Method To Automate Unbiased Stereology Cell Counting, Saeed Alahmari

USF Tampa Graduate Theses and Dissertations

Cell quantification in histopathology images plays a significant role in understanding and diagnosing diseases such as cancer and Alzheimers. The gold-standard for quantifying cells in tissue sections is the unbiased stereology approach. Unfortunately, in unbiased stereology current practices rely on a well-trained human to manually count hundreds of cells in microscopy images. However, this human-based manual approach is time-consuming, labor-intensive, subject to human errors, recognition bias, fatigue, variable training, poor reproducibility, and inter-observer error. Thus, the lack of high-throughput technology for automating unbiased stereology analyses remains a major obstacle to further progress in a wide range of neuroscience and cancer …

Next-Generation Self-Organizing Communications Networks: Synergistic Application Of Machine Learning And User-Centric Technologies, Chetana V. Murudkar

USF Tampa Graduate Theses and Dissertations

The telecommunications industry is going through a metamorphic journey where the 5G and 6G technologies will be deeply rooted in the society forever altering how people access and use information. In support of this transformation, this dissertation proposes a fundamental paradigm shift in the design, performance assessment, and optimization of wireless communications networks developing the next-generation self-organizing communications networks with the synergistic application of machine learning and user-centric technologies.

This dissertation gives an overview of the concept of self-organizing networks (SONs), provides insight into the “hot” technology of machine learning (ML), and offers an intuitive understanding of the user-centric (UC) …

The Effects Of Surface-Water Flow On The Quality Of Groundwater And Surface-Water Systems, Quanghee Yi

USF Tampa Graduate Theses and Dissertations

My research has focused on the effects of surface-water flow on the quality of groundwater and surfacewater systems. For the first part of my research (Chapter 2 ), I s tudied the effects of s urface flow system changes in the water-conservation areas and canals in southeast Florida on the quality of groundwater in the surficial aquifer system.

For the second part of my research, by developing analytical models using the superposition method, I investigated the effects of bidirectional surface-water flow on the conservative contaminant concentrations (Chapter 4) and mean residence time (Chapter 5) in streams and rivers as well …

Structural And Agricultural Value At Risk In Florida From Flooding During Hurricane Irma, Alexander J. Miller

USF Tampa Graduate Theses and Dissertations

Flooding is the most costly type of natural disaster, as well as the most frequent. To provide risk-based flood insurance, providers such as FEMA must be able to accurately determine an asset’s risk of flooding. Additionally, after a flooding event, providers need to quickly determine the direct damages that occurred to verify insurance claims and provide assistance to the affected communities. Many current approaches to flood risk and flood damage estimation involve the use of data or statistical extrapolation that can add various sources of uncertainty into the final damage estimate. In order to reduce uncertainties in flood risk analyses, …

Van Der Waals Epitaxy Of Ultrathin Early Transition Metal (Ti & V) (Di)Selenides: Charge And Magnetic Order In The Ultrathin Limit, Manuel Bonilla Lopez

USF Tampa Graduate Theses and Dissertations

Since the isolation of graphene in 2004, two-dimensional (2D) layered materials, specially the transition metal dichalcogenides (TMDs), have attracted immense interest from theoreticians and experimentalist due to the diversity of properties presented in this family of materials. The main reason for the interest in such materials has been the observation of emergent properties as a consequence of the reduced dimensions, i.e. the monolayer regime. Initially the monolayer regime was obtained via the scotch-tape method. The implementation of exfoliation techniques was successful since layered 2D materials are composed of stacked layers held together by weak van der Walls forces that permits …

Biogeochemical Cycling Of Nutrients And Carbon In Subtropical Wetlands, Lauren N. Griffiths

USF Tampa Graduate Theses and Dissertations

As human development intensifies, ecosystems around the word are being exponentially destroyed and degraded. Wetlands have the capacity to mitigate some of the possible problems by retaining nutrients and carbon, keeping them from harming downstream ecosystems or being released into the atmosphere. This project focuses on the processes that make wetlands successful by studying two unique ecosystems: 1) a created urban stormwater treatment wetland and 2) mangrove wetlands in Florida and Puerto Rico that were affected by hurricanes in 2017.

The first phase of this study investigates the role of sedimentation and vegetative and algal uptake of nutrients to retain …

Using Geophysical And Geodetic Data To Improve Natural And Human-Induced Hazard Assessments, Fanghui Deng

USF Tampa Graduate Theses and Dissertations

I use geophysical and geodetic data to study dynamics of the Earth System, including volcanoes and induced seismicity, aiming to improve related hazard assessment at different time and space scales. My dissertation consists of the following three projects: 1) Geophysical model for the origin of volcano vent clusters (Deng et al., 2017). We developed a conceptual model to simulate long-term magma transport to explain the origin of volcanic vent clusters in Quaternary Colorado Plateau volcanic fields. We used density contrast inverted from gravity data to constrain the magma transport model. The development of vent clusters appears to be influenced by …

Development Of A Benthic Foraminifera Based Marine Biotic Index (Foram-Ambi) For The Gulf Of Mexico: A Decision Support Tool, Bryan O'Malley

USF Tampa Graduate Theses and Dissertations

The Gulf of Mexico (GoM) is an economically important region (e.g. oil and gas, fisheries) and with the expansion of oil drilling, harmful algal bloom events, oil blowouts, dead zones, anthropogenic eutrophication and contaminant loading, it is important that the ecological quality statuses (EcoQS) of different localities in the Gulf are closely monitored. The EcoQS, as implemented by the European Water Framework Directive, is an effective tool for monitoring ecological health and developing reference conditions. One such index used to define EcoQS is the AZTI Marine Biotic Index (AMBI), which pairs species abundance with environmental stressors. Benthic foraminifera are ideal …

Bayesian Reliability Analysis For Optical Media Using Accelerated Degradation Test Data, Kun Bu

USF Tampa Graduate Theses and Dissertations

ISO (the International Organization for Standardization) 10995:2011 is the inter-national standard providing guidelines for assessing the reliability and service life of optical media, which is designed to be highly reliable and possesses a long lifetime. A well-known challenge of reliability analysis for highly reliable devices is that it is hard to obtain sufficient failure data under their normal use conditions. Accelerated degradation tests (ADTs) are commonly used to quickly obtain physical degradation data under elevated stress conditions, which are then extrapolated to predict reliability under the normal use condition. This standard achieves the estimation of the lifetime of recordable media, …

Investigating The Isotope Signatures Of Dissolved Iron In The Southern Atlantic Ocean, Brent A. Summers

USF Tampa Graduate Theses and Dissertations

Iron (Fe), used as a cofactor in nitrogen fixation and photosynthesis by oceanic microorganisms, has extremely low dissolved concentrations in the surface ocean, leading to widespread limitation of phytoplankton growth. Dissolved Fe isotope ratios (δ56Fe) have been shown to be useful in helping to quantify the sources and cycling of Fe in the oceans if Fe source signatures and fractionation processes are well understood. Here, this thesis presents data from GEOTRACES section GA10W, and investigate the isotopic signature of sediment-derived dissolved Fe from the South Atlantic margins. My results show that there are both shallow (δ56Fe of -0.2‰) and deep …

Action Recognition Using The Motion Taxonomy, Maxat Alibayev

USF Tampa Graduate Theses and Dissertations

In the last years, modern action recognition frameworks with deep architectures have achieved impressive results on the large-scale activity datasets. All state-of-the-art models share one common attribute: two-stream architectures. One deep model takes RGB frames, while the other model is fed with pre-computed optical flow vectors. The outputs of both models are combined to be used as a final probability distribution for the action classes. When comparing the results of individual models with the fused model, it is common to see that that latter method is more superior. Researchers explain that phenomena with the fact that optical flow vectors serve …