Physical Sciences and Mathematics Commons^™

Evaporite Karst Geohazards In The Delaware Basin, Texas: Review Of Traditional Karst Studies Coupled With Geophysical And Remote Sensing Characterization, Kevin W. Stafford, Wesley A. Brown, Jon T. Ehrhart, Adam F. Majzoub, Jonathan D. Woodard

International Journal of Speleology

Evaporite karst throughout the Gypsum Plain of west Texas is complex and extensive, including manifestations ranging from intrastratal brecciation and hypogene caves to epigene features and suffosion caves. Recent advances in hydrocarbon exploration and extraction has resulted in increased infrastructure development and utilization in the area; as a result, delineation and characterization of potential karst geohazards throughout the region have become a greater concern. While traditional karst surveys are essential for delineating the subsurface extent and morphology of individual caves for speleogenetic interpretation, these methods tend to underestimate the total extent of karst development and require surficial manifestation of karst …

Complex Electric-Field Induced Phenomena In Ferroelectric/Antiferroelectric Nanowires, Ryan Christopher Herchig

USF Tampa Graduate Theses and Dissertations

Perovskite ferroelectrics and antiferroelectrics have attracted a lot of attention owing to their potential for device applications including THz sensors, solid state cooling, ultra high density computer memory, and electromechanical actuators to name a few. The discovery of ferroelectricity at the nanoscale provides not only new and exciting possibilities for device miniaturization, but also a way to study the fundamental physics of nanoscale phenomena in these materials. Ferroelectric nanowires show a rich variety of physical characteristics which are advantageous to the design of nanoscale ferroelectric devices such as exotic dipole patterns, a strong dependence of the polarization and phonon frequencies …

Semantic Description Of Activities In Videos, Fillipe Dias Moreira De Souza

USF Tampa Graduate Theses and Dissertations

Description of human activities in videos results not only in detection of actions and objects but also in identification of their active semantic relationships in the scene. Towards this broader goal, we present a combinatorial approach that assumes availability of algorithms for detecting and labeling objects and actions, albeit with some errors. Given these uncertain labels and detected objects, we link them into interpretative structures using domain knowledge encoded with concepts of Grenander’s general pattern theory. Here a semantic video description is built using basic units, termed generators, that represent labels of objects or actions. These generators have multiple out-bonds, …

"There Is No Planet B": Frame Disputes Within The Environmental Movement Over Geoengineering, David Russell Zeller Jr.

USF Tampa Graduate Theses and Dissertations

This dissertation examines frame disputes within the environmental movement over geoengineering proposals. Among other core framing tasks, social movement organizations must evaluate solutions and strategies for the social problems they seek to address. These framings are frequently disputed by those within the movement. Recent controversies regarding a set of climate intervention proposals commonly known as geoengineering offer the opportunity to document the ongoing construction of competing visions of environmental sustainability. The nascent quality of these proposals generate dissonant framings—episodes where organizations within the environmental movement exhibit disagreement about one or more core framing tasks—a situation Goffman referred to as a …

Exploring Student Learning In Post-Secondary General Chemistry: Novel Tools For Measuring Linked Concepts And Study Habits, Li Ye

USF Tampa Graduate Theses and Dissertations

This dissertation presents novel tools to help instructors measure students linking of content knowledge and the actions students perform for studying in the context of post-secondary General Chemistry.

The first tool described in this work is Creative Exercises (CEs), an open-ended assessment that has the potential to promote students making connections across the content covered in General Chemistry. Students are given a simple prompt that describes a chemistry situation, and asked to write as many statements as they can that are correct, distinct and relevant to the prompt and the course content. The written responses to CEs from both in-class …

Germania- And Silica-Based Perfluorinated And Non-Fluorinated Sol-Gel Sorbents For Capillary Microextraction In Chromatographic Analysis, Emre Seyyal

USF Tampa Graduate Theses and Dissertations

Sample preparation is the most time-consuming and error-prone step in chemical analysis. Miniaturization and automation of the sample preparation equipment eliminating or reducing the use of hazardous organic solvents, online hyphenation of sample preparation with analytical instruments in a cost-effective way are important factors that need to be considered to design and implement innovative sample preparation techniques and strategies. Solid-phase microextraction (SPME) is a simple, environmentally benign technique well suited for hyphenation with analytical instruments. However, poor coating stability is a significant drawback of SPME employing conventionally prepared coatings. This shortcoming arises from the lack of chemical bonding between the …

The Influence Of Tropical Forests And Climate Change On The Fates Of Select Organic Pollutants In A Jamaican Watershed, Kayon Barrett

USF Tampa Graduate Theses and Dissertations

Many organic compounds, although beneficial, are associated with negative health and ecological impacts. It is therefore imperative to understand the environmental fates of these contaminants. Whereas the fates and health impacts of many persistent organic pollutants have been extensively examined, there is limited research characterizing the fates of these and the less persistent organic compounds in tropical multi-use watersheds. This study therefore aimed to evaluate the roles of forests and climate change on the environmental fates and health impacts of select organic chemicals in the Rio Cobre watershed, a tropical river basin in Jamaica. A total of 16 organic compounds …

Multi-Scale Approaches For Evaluating The Success Of Habitat Restoration In Tampa Bay, Florida, Stephanie Thompson Powers

USF Tampa Graduate Theses and Dissertations

This research aims to further the understanding of ecological restoration success in the Tampa Bay, Florida, region. Although over four hundred restoration projects have been completed in the bay area, knowledge of their success has been hindered by the lack of assessment and transfer of information concerning project outcomes. Without comprehensive project assessment, local science will be limited in its ability to inform practice because we lack the advantage of past knowledge.

Using a multi-scaled approach, a diverse set of restoration projects are evaluated, providing information on how the projects are contributing to defined targets established by the Tampa Bay …

Robustness Of The Within- And Between-Series Estimators To Non-Normal Multiple-Baseline Studies: A Monte Carlo Study, Seang-Hwane Joo

USF Tampa Graduate Theses and Dissertations

In single-case research, multiple-baseline (MB) design is the most widely used design in practical settings. It provides the opportunity to estimate the treatment effect based on not only within-series comparisons of treatment phase to baseline phase observations, but also time-specific between-series comparisons of observations from those that have started treatment to those that are still in the baseline. In MB studies, the average treatment effect and the variation of these effects across multiple participants can be estimated using various statistical modeling methods. Recently, two types of statistical modeling methods were proposed for analyzing MB studies: a) within-series model and b) …

Coherent Response Of Two Dimensional Electron Gas Probed By Two Dimensional Fourier Transform Spectroscopy, Jagannath Paul

USF Tampa Graduate Theses and Dissertations

Advent of ultrashort lasers made it possible to probe various scattering phenomena in materials that occur in a time scale on the order of few femtoseconds to several tens of picoseconds. Nonlinear optical spectroscopy techniques, such as pump-probe, transient four wave mixing (TFWM), etc., are very common to study the carrier dynamics in various material systems. In time domain, the transient FWM uses several ultrashort pulses separated by time delays to obtain the information of dephasing and population relaxation times, which are very important parameters that govern the carrier dynamics of materials. A recently developed multidimensional nonlinear optical spectroscopy is …

Interference Of Light In Multilayer Metasurfaces: Perfect Absorber And Antireflection Coating, Khagendra Prasad Bhattarai

USF Tampa Graduate Theses and Dissertations

We have studied several metamaterials structures with multiple layers by explaining them theoretically and verifying experimentally. The engineered structures we have designed work either as a perfect absorber or antireflection coating. The multilayer model as we call it Three Layer Model (TLM) has been developed, which gives the total reflection and transmission as a function of reflection and transmission of individual layers. By manipulating the amplitude and phase of the reflection and the transmission of the individual layers, we can get the required functionality of the optoelectronic devices. To get zero reflection in the both perfect absorber and the antireflection …

On The Conformational Dynamics Of Dna: A Perspective From Molecular Dynamics Simulations, Ning Ma

USF Tampa Graduate Theses and Dissertations

The main focus of my dissertation is on the conformational motion of DNA, studied by applying tools from the computational chemistry field. In addition, studies of relative α- and 310 helical stabilities in peptides/mini-proteins, and a molecular flooding study of the retinoid X-receptor as part of a continuing drug design effort are presented. In molecular biology, it has been well known that sequence determines structure, and structure controls function. For proteins or DNA to work properly, the correct configuration is required. Mutations may alter the structure, which can cause malfunction. Non-mutational effects, such as a change in environment may also …

Dynamics Of Multicultural Social Networks, Kristina B. Hilton

USF Tampa Graduate Theses and Dissertations

Historically human endeavors around the globe are in search of bilateral relationships. Knowledge and commerce has played a very significant role in increasing the ability for humans to connect for the betterment of the human species. As the means of communication improve, mutual benefits to the community as a whole also increase. Moreover, the benefits are filtered down to members of the overall community. Recent advancement in electronic communication technologies and in knowledge, in particular, physical, chemical, engineering and medical sciences and philosophies, have facilitated nearly instantaneous multi-cultural interactions. Local problems and solutions have become global. This has generated a …

Evolution Characteristics Of Landscape Ecological Risk Patterns In Coastal Zones In Zhejiang Province, China, Jialin Li, Ruiliang Pu, Hongbo Gong, Xu Luo, Mengyao Ye, Baixiang Feng

School of Geosciences Faculty and Staff Publications

Analyzing evolution characteristics of landscape ecological risk patterns would help establish ecological risk early warning mechanism, reduce the ecological risk probability and promote coastal landscape pattern optimization. In this study, landscape pattern indices were first calculated by using multitemporal Landsat TM images acquired in years 1990, 2000 and 2010, then landscape ecological risk pattern evolution models and the spatiotemporal evolutions of ecological risk patterns of coastal zones in Zhejiang province, China were constructed and analyzed. The results demonstrate that (1) greater changes have taken place in landscape structures during the two decades, and (2) the areas of cropland, sea, woodland …

Holocene Winter Climate Variability In Central And Eastern Europe, Aurel Perşoiu, Bogdan P. Onac, Jonathan G. Wynn, Maarten Blaauw, Monica Ionita, Margareta Hansson

School of Geosciences Faculty and Staff Publications

Among abundant reconstructions of Holocene climate in Europe, only a handful has addressed winter conditions, and most of these are restricted in length and/or resolution. Here we present a record of late autumn through early winter air temperature and moisture source changes in East-Central Europe for the Holocene, based on stable isotopic analysis of an ice core recovered from a cave in the Romanian Carpathian Mountains. During the past 10,000 years, reconstructed temperature changes followed insolation, with a minimum in the early Holocene, followed by gradual and continuous increase towards the mid-to-late-Holocene peak (between 4-2 kcal BP), and finally by …

Open Data And Digital Morphology, Thomas G. Davies, Imran A. Rahman, Stephan Lautenschlager, John A. Cunningham, Robert J. Asher, Paul M. Barrett, Karl T. Bates, Stefan Bengtson, Roger B. J. Benson, Doug M. Boyer, José Braga, Jen A. Bright

School of Geosciences Faculty and Staff Publications

Over the past two decades, the development of methods for visualizing and analysing specimens digitally, in three and even four dimensions, has transformed the study of living and fossil organisms. However, the initial promise that the widespread application of such methods would facilitate access to the underlying digital data has not been fully achieved. The underlying datasets for many published studies are not readily or freely available, introducing a barrier to verification and reproducibility, and the reuse of data. There is no current agreement or policy on the amount and type of data that should be made available alongside studies …

Modeling In Finance And Insurance With Levy-It'o Driven Dynamic Processes Under Semi Markov-Type Switching Regimes And Time Domains, Patrick Armand Assonken Tonfack

USF Tampa Graduate Theses and Dissertations

Mathematical and statistical modeling have been at the forefront of many significant advances in many disciplines in both the academic and industry sectors. From behavioral sciences to hard core quantum mechanics in physics, mathematical modeling has made a compelling argument for its usefulness and its necessity in advancing the current state of knowledge in the 21rst century. In Finance and Insurance in particular, stochastic modeling has proven to be an effective approach in accomplishing a vast array of tasks: risk management, leveraging of investments, prediction, hedging, pricing, insurance, and so on. However, the magnitude of the damage incurred in recent …

Optimization And Performance Study Of Select Heating Ventilation And Air Conditioning Technologies For Commercial Buildings, Rajeev Kamal

USF Tampa Graduate Theses and Dissertations

Buildings contribute a significant part to the electricity demand profile and peak demand for the electrical utilities. The addition of renewable energy generation adds additional variability and uncertainty to the power system. Demand side management in the buildings can help improve the demand profile for the utilities by shifting some of the demand from peak to off-peak times.

Heating, ventilation and air-conditioning contribute around 45% to the overall demand of a building. This research studies two strategies for reducing the peak as well as shifting some demand from peak to off-peak periods in commercial buildings:

1. Use of gas heat …

Mitigation Of Insider Attacks For Data Security In Distributed Computing Environments, Santosh Aditham

USF Tampa Graduate Theses and Dissertations

In big data systems, the infrastructure is such that large amounts of data are hosted away from the users. Information security is a major challenge in such systems. From the customer’s perspective, one of the big risks in adopting big data systems is in trusting the service provider who designs and owns the infrastructure, with data security and privacy. However, big data frameworks typically focus on performance and the opportunity for including enhanced security measures is limited. In this dissertation, the problem of mitigating insider attacks is extensively investigated and several static and dynamic run-time techniques are developed. The proposed …

Quantity Trumps Quality: Bayesian Statistical Accumulation Modeling Guides Radiocarbon Measurements To Construct A Chronology In Real-Time, Devon Robert Firesinger

USF Tampa Graduate Theses and Dissertations

The development of an accurate and precise geochronology is imperative to understanding archives containing information about Earth’s past. Unable to date all intervals of an archive, researchers use methods of interpolation to approximate age between dates. Sections of the radiocarbon calibration curve can induce larger chronological uncertainty independent of instrumental precision, meaning even a precise date may carry inflated error in its calibration to a calendar age. Methods of interpolation range from step-wise linear regression to, most recently, Bayesian statistical models. These employ prior knowledge of accumulation rate to provide a more informed interpolation between neighboring dates. This study uses …

Sustainable Development Through Urban Agriculture, Eric R. R. Weaver

USF Tampa Graduate Theses and Dissertations

This document includes three completed publications to represent Urban Agriculture as a ideal solution to meet the UN Sustainable Development Goals. The first publication (Weaver, 2017a) provided in Chapter Two examines the stormwater Best Management Practices (BMP) modelling parameters for the current EPA Stormwater Management Model (SWMM) as the first step to developing Urban Agriculture BMPs. The second publication (Weaver, 2015) provided in Chapter Three highlights how many high-rated scholars have identified agriculture as a critical driver for the planetary systems impacts we find with community development. The third publication (Weaver, 2017b) provided in Chapter Four breaks down a completely …

Scalable Unsupervised Learning With Game Theory, Alireza Chakeri

USF Tampa Graduate Theses and Dissertations

Recently dominant sets, a generalization of the notion of the maximal clique to edge-weighted graphs, have proven to be an effective tool for unsupervised learning and have found applications in different domains. Although, they were initially established using optimization and graph theory concepts, recent work has shown fascinating connections with evolutionary game theory, that leads to the clustering game framework. However, considering size of today's data sets, existing methods need to be modified in order to handle massive data. Hence, in this research work, first we address the limitations of the clustering game framework for large data sets theoretically. We …

Abundance And Habitat Preferences Of Introduced Muscovy Ducks (Cairina Moschata), Jacqueline Marie Perry Cahanin

USF Tampa Graduate Theses and Dissertations

Muscovy ducks are native only to Central and South America, Mexico, and parts of southern Texas and are considered invasive in some areas outside of their native range. Although they have been introduced worldwide, they remain largely unstudied. The primary focus of this study was to relate Muscovy duck abundance to habitat characteristics of wetlands in Tampa, Florida. Muscovy abundance was measured using point count methods at 21 wetland sites that occur within an eight km radius of the University of South Florida’s main campus. Habitat features at these sites were assessed using field methods and Geographic Information Systems (GIS) …

3d Cave And Ice Block Morphology From Integrated Geophysical Methods: A Case Study At Scărişoara Ice Cave, Romania, Jackson Durain Hubbard

USF Tampa Graduate Theses and Dissertations

Scărişoara Ice Cave has been a catalyst of scientific intrigue and effort for over 150 years. These efforts have revealed and described countless natural phenomena – and in the process have made it one of the most studied caves in the world.

Of especial interest is the massive ice block located within its Great Hall and scientific reservations. The ice block, which is the oldest and largest known to exist in a cave, has been the focus of multiple surveying and mapping efforts, typically ones utilizing traditional equipment. In this study, the goals were to reconstruct the ice block/cave floor …

Tradeoffs In Protocol Designs For Collaborative Authentication, Jacob Venne

USF Tampa Graduate Theses and Dissertations

Authentication is a crucial tool used in access control mechanisms to verify a user’s identity. Collaborative Authentication (co-authentication) is a newly proposed authentication scheme designed to improve on traditional token authentication. Co-authentication works by using multiple user devices as tokens to collaborate in a challenge and authenticate a user request on single device.

This thesis adds two contributions to the co-authentication project. First, a detailed survey of applications that are suitable for adopting co-authentication is presented. Second, an analysis of tradeoffs between varying protocol designs of co-authentication is performed to determine whether, and how, any designs are superior to other …

Using Remote Sensing To Evaluate Wetland Recovery In The Northern Tampa Bay Area Following Reduction In Groundwater Withdrawals, Amor Elder

USF Tampa Graduate Theses and Dissertations

In the past, the Northern Tampa Bay Area (NTBA) wetlands saw severe declines in hydrologic conditions due to excessive groundwater withdrawal rates. Eventually these rates were reduced to allow the wetlands to recover. To monitor this recovery, the Southwest Florida Water Management district (SWFWMD) set up a fieldwork based scoring methodology, called the Wetlands Assessment Procedure (WAP). WAP has been used in many studies of the area since groundwater withdrawal reductions; with many of those studies finding the recovery to be mixed at best. However, these studies were very limited in the number of wetlands they could assess due to …

Characterizing The Evolution Of Slab Inputs In The Earliest Stages Of Subduction: Preliminary Evidence From The Fluid-Mobile Element (B, Cs, As, Li) Systematics Of Izu-Bonin Boninitic Glasses Recovered During Iodp Expedition 352, Keir Aavon Sanatan

USF Tampa Graduate Theses and Dissertations

Fluid-mobile elements (FMEs) such as B, Cs, As, Li and Tl can mobilize readily under low P-T conditions (0.2-0.5 GPa). This makes them effective geochemical tracers that can be used as a way of tracking fluid-rock exchanges at the shallow depths encountered in the earliest stages of subduction.

The Izu-Bonin-Mariana (IBM) subduction system is unique in that it preserves a record of the sequences produced from the onset of subduction through the development of arc magmatism. International Ocean Discovery Program (IODP) Expedition 352 recovered >800m of boninite core material from the earliest IBM magmatic events.

Select boninitic glasses from these …

Schreier Graphs Of Thompson's Group T, Allen Pennington

USF Tampa Graduate Theses and Dissertations

Thompson’s groups F, T, and V represent crucial examples of groups in geometric group theory that bridge it with other areas of mathematics such as logic, computer science, analysis, and geometry. One of the ways to study these groups is by understanding the geometric meaning of their actions. In this thesis we deal with Thompson’s group T that acts naturally on the unit circle S¹, that is identified with the segment [0, 1] with the end points glued together. The main result of this work is the explicit construction of the Schreier graph of T with …

Linear Extremal Problems In The Hardy Space HP For 0 < P < 1, Robert Christopher Connelly

USF Tampa Graduate Theses and Dissertations

In this thesis, we consider linear extremal problems in the H^p spaces. For many of these extremal problems, a unique solution can be guaranteed. We will examine some of the classical examples of extremal problems in these spaces. With this framework in place we will then consider a particular problem which does not always have a unique solution.

Forging Blockchains: Spatial Production And Political Economy Of Decentralized Cryptocurrency Code/Spaces, Joe Blankenship

USF Tampa Graduate Theses and Dissertations

Cryptocurrencies and blockchains are increasingly used, implemented and adapted for numerous purposes; people and businesses are integrating these technologies into their practices and strategies, creating new political economies and spaces in and of everyday life. This thesis seeks to develop a foundation of geographic theory for the study of spatial production within and surrounding blockchain technologies focusing on acute studies of Bitcoin as cryptocurrency, Ethereum as digital marketplace, and their conditions of possibility as decentralized autonomous organizations. Utilizing concepts from Henri Lefebvre's Production of Space, this thesis situates blockchain technologies within the wider discussion about the political economy of …