Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

USF Tampa Graduate Theses and Dissertations

Discipline
Keyword
Publication Year
File Type

Articles 631 - 660 of 1607

Full-Text Articles in Physical Sciences and Mathematics

Hamiltonian Structures And Riemann-Hilbert Problems Of Integrable Systems, Xiang Gu Jul 2018

Hamiltonian Structures And Riemann-Hilbert Problems Of Integrable Systems, Xiang Gu

USF Tampa Graduate Theses and Dissertations

We begin this dissertation by presenting a brief introduction to the theory of solitons and integrability (plus some classical methods applied in this field) in Chapter 1, mainly using the Korteweg-de Vries equation as a typical model. At the end of this Chapter a mathematical framework of notations and terminologies is established for the whole dissertation.

In Chapter 2, we first introduce two specific matrix spectral problems (with 3 potentials) associated with matrix Lie algebras $\mbox{sl}(2;\mathbb{R})$ and $\mbox{so}(3;\mathbb{R})$, respectively; and then we engender two soliton hierarchies. The computation and analysis of their Hamiltonian structures based on the trace identity affirms …


Human Activity Recognition Based On Transfer Learning, Jinyong Pang Jul 2018

Human Activity Recognition Based On Transfer Learning, Jinyong Pang

USF Tampa Graduate Theses and Dissertations

Human activity recognition (HAR) based on time series data is the problem of classifying various patterns. Its widely applications in health care owns huge commercial benefit. With the increasing spread of smart devices, people have strong desires of customizing services or product adaptive to their features. Deep learning models could handle HAR tasks with a satisfied result. However, training a deep learning model has to consume lots of time and computation resource. Consequently, developing a HAR system effectively becomes a challenging task. In this study, we develop a solid HAR system using Convolutional Neural Network based on transfer learning, which …


Application Of The Fusion Model For Cognitive Diagnostic Assessment With Non-Diagnostic Algebra-Geometry Readiness Test Data, Robert H. Fay Jul 2018

Application Of The Fusion Model For Cognitive Diagnostic Assessment With Non-Diagnostic Algebra-Geometry Readiness Test Data, Robert H. Fay

USF Tampa Graduate Theses and Dissertations

This study retrofitted a Diagnostic Classification Model (DCM) known as the Fusion model onto non-diagnostic test data from of the University of Chicago School Mathematics Project (UCSMP) Algebra and Geometry Readiness test post-test used with Transition Mathematics (Third Edition, Field-Trial Version). The test contained 24 multiple-choice middle school math items, and was originally given to 95 advanced 6th grade and 293 7th grade students. The use of these test answers for this study was an attempt to show that by using cognitive diagnostic analysis techniques on test items not constructed for that purpose, highly predictable multidimensional cognitive attribute profiles for …


Generalizations Of Quandles And Their Cohomologies, Matthew J. Green Jul 2018

Generalizations Of Quandles And Their Cohomologies, Matthew J. Green

USF Tampa Graduate Theses and Dissertations

Quandles are distributive algebraic structures originally introduced independently by David Joyce and Sergei Matveev in 1979, motivated by the study of knots. In this dissertation, we discuss a number of generalizations of the notion of quandles. In the first part of this dissertation we discuss biquandles, in the context of augmented biquandles, a representation of biquandles in terms of actions of a set by an augmentation group. Using this representation we are able to develop a homology and cohomology theory for these structures.

We then introduce an n-ary generalization of the notion of quandles. We discuss a number of properties …


Automatic Multimodal Assessment Of Neonatal Pain, Ghada Zamzmi Jul 2018

Automatic Multimodal Assessment Of Neonatal Pain, Ghada Zamzmi

USF Tampa Graduate Theses and Dissertations

For several decades, pediatricians used to believe that neonates do not feel pain. The American Academy of Pediatrics (AAP) recognized neonates' sense of pain in 1987. Since then, there have been many studies reporting a strong association between repeated pain exposure (under-treatment) and alterations in brain structure and function. This association has led to the increased use of anesthetic medications. However, recent studies found that the excessive use of analgesic medications (over-treatment) can cause many side effects. The current standard for assessing neonatal pain is discontinuous and suffers from inter-observer variations, which can lead to over- or under-treatment. Therefore, it …


Evaluation Of Trace-Metal And Isotopic Records As Techniques For Tracking Lifetime Movement Patterns In Fishes, Jennifer E. Granneman Jul 2018

Evaluation Of Trace-Metal And Isotopic Records As Techniques For Tracking Lifetime Movement Patterns In Fishes, Jennifer E. Granneman

USF Tampa Graduate Theses and Dissertations

The focus of this work was on the use of otolith microchemistry and fish eye lens chemical profiles to measure fish movement and provided indirect support for the use of otolith microchemistry to examine exposure to crude oil. Chapter 1 provides an introduction to the applications of otolith microchemistry and eye lens isotopic profiles. In the second chapter, which examined associations between metal exposure and lesion formation in fishes collected after the Deepwater Horizon (DWH) oil spill, I did not observe any change in oil-associated metal concentrations in otoliths coinciding with the timing of the DWH oil spill. This suggests …


Interrogation Of Protein Function With Peptidomimetics, Olapeju Bolarinwa Jul 2018

Interrogation Of Protein Function With Peptidomimetics, Olapeju Bolarinwa

USF Tampa Graduate Theses and Dissertations

Proteins can be described as the “machineries” responsible for almost all tasks in the levels of organizational complexity in multi-cellular organisms namely: the cells, tissues, organs and systems. Any disorder in the function of a protein at any of these levels could result in disease, and a study of protein function is critical to understanding the pathological features of the disease at the molecular level. A quick glance at these abundantly present proteins reveals two striking features: large diversity of biological function, and the variations in structural complexity, which varies from simple random coils, to turns and helices, and on …


Spatial And Temporal Distributions Of Pelagic Sargassum In The Intra-Americas Sea And Atlantic Ocean, Mengqiu Wang Jul 2018

Spatial And Temporal Distributions Of Pelagic Sargassum In The Intra-Americas Sea And Atlantic Ocean, Mengqiu Wang

USF Tampa Graduate Theses and Dissertations

Pelagic Sargassum is one type of marine macroalgae that is known to be abundant in the Gulf of Mexico and Sargasso Sea. It is also known to serve as a critical habitat for many marine animals. In the past few years, large amounts of Sargassum have been reported in the Tropical Atlantic and Caribbean Sea (CS), causing significant environmental and economic problems. The goal of this study is to improve the understanding of Sargassum distributions, quantity, transport pathways, and bloom mechanisms in the CS and Tropic Atlantic through combining a variety of techniques including satellite remote sensing, field and laboratory …


Analytics For Novel Consumer Insights (A Three Essay Dissertation), Utkarsh Shrivastava Jul 2018

Analytics For Novel Consumer Insights (A Three Essay Dissertation), Utkarsh Shrivastava

USF Tampa Graduate Theses and Dissertations

Both literature and practice have investigated how the vast amount of ever increasing customer information can inform marketing strategy and decision making. However, the customer data is often susceptible to modeling bias and misleading findings due to various factors including sample selection and unobservable variables. The available analytics toolkit has continued to develop but in the age of nearly perfect information, the customer decision making has also evolved. The dissertation addresses some of the challenges in deriving valid and useful consumer insights from customer data in the digital age. The first study addresses the limitations of traditional customer purchase measures …


Machine Learning Methods For Network Intrusion Detection And Intrusion Prevention Systems, Zheni Svetoslavova Stefanova Jul 2018

Machine Learning Methods For Network Intrusion Detection And Intrusion Prevention Systems, Zheni Svetoslavova Stefanova

USF Tampa Graduate Theses and Dissertations

Given the continuing advancement of networking applications and our increased dependence upon software-based systems, there is a pressing need to develop improved security techniques for defending modern information technology (IT) systems from malicious cyber-attacks. Indeed, anyone can be impacted by such activities, including individuals, corporations, and governments. Furthermore, the sustained expansion of the network user base and its associated set of applications is also introducing additional vulnerabilities which can lead to criminal breaches and loss of critical data. As a result, the broader cybersecurity problem area has emerged as a significant concern, with many solution strategies being proposed for both …


Theory And Application Of Geophysical Geodesy For Studying Earth Surface Deformation, Makan A. Karegar Jul 2018

Theory And Application Of Geophysical Geodesy For Studying Earth Surface Deformation, Makan A. Karegar

USF Tampa Graduate Theses and Dissertations

An interdisciplinary approach at the interface between geodesy and geophysics has recently resolved several Earth science problems at regional and global scales. I use the term “geophysical geodesy” to distinguish the technical and theoretical aspect of geodesy from geophysical applications of geodetic techniques. Using a wide range of Earth observation data, I study the spatio-temporal characteristics of Earth surface deformation in the United States associated with several geophysical processes, including natural and anthropogenic subsidence and uplift, regional relative sea-level rise, and continental hydrological loading. The theoretical portion of this dissertation applies loading theory and develops a new hybrid method to …


The Effect Of Processing Conditions On The Energetic Diagram Of Cdte Thin Films Studied By Photoluminescence, Shamara P. Collins Jul 2018

The Effect Of Processing Conditions On The Energetic Diagram Of Cdte Thin Films Studied By Photoluminescence, Shamara P. Collins

USF Tampa Graduate Theses and Dissertations

The photovoltaic properties of CdTe-based thin films depend on recombination levels formed in the CdTe layer and at the heterojunction. The localized states are resultant of structural defects (metal sublattice, chalcogen sublattice, interstitial), controlled doping, deposition process, and/or post-deposition annealing. The photoluminescence study of CdTe thin films, from both the bulk and heterojunction, can reveal radiative states due to different defects or impurities. Identification of defects allows for potential explanation of their roles and influence on solar cell performance. A thorough understanding of the material properties responsible for solar cell performance is critical in further advancing the efficiency of devices. …


An Interdisciplinary Approach To Understanding Predator-Prey Relationships In A Changing Ocean: From System Design To Education, Ileana M. Freytes-Ortiz Jul 2018

An Interdisciplinary Approach To Understanding Predator-Prey Relationships In A Changing Ocean: From System Design To Education, Ileana M. Freytes-Ortiz

USF Tampa Graduate Theses and Dissertations

Climate change is ecologically and socially complex, deemed the most important issue of our generation. Through this dissertation I have approached climate change research through an interdisciplinary perspective, investigating how this phenomenon will affect marine ecological systems, how we can better develop experimental systems to answer ecological questions, and how we can effectively educate about this issue.

In Chapter 2, I provided accessible alternatives for researching the effects of climate change (elevated temperatures and pCO2) on marine ecosystems. I designed, built, and troubleshooted two accurate and inexpensive climate-controlled experimental systems capable of maintaining target conditions: a temperature-controlled system and an …


An Effectual Approach For The Development Of Novel Applications On Digital Platforms, Onkar Shamrao Malgonde Jun 2018

An Effectual Approach For The Development Of Novel Applications On Digital Platforms, Onkar Shamrao Malgonde

USF Tampa Graduate Theses and Dissertations

The development of novel software applications on digital platforms differs from traditional software development and provides unique challenges to the software development manager and team. Application producers must achieve application-platform match, application-market match, value propositions exceeding platform’s core value propositions, and novelty. These desired properties support a new vision of the software development team as entrepreneurs with a goal of developing novel applications on digital platforms. Digital platforms are characterized by an uncertain, risky, and resource-constrained environment, where existing approaches—plan-driven, ad-hoc, and controlled-flexible—have limited applicability. Building on the theoretical basis of the theory of effectuation from the entrepreneurship domain, this …


Offensive And Defensive Security For Everyday Computer Systems, Ian Markwood Jun 2018

Offensive And Defensive Security For Everyday Computer Systems, Ian Markwood

USF Tampa Graduate Theses and Dissertations

This dissertation treats a variety of topics in the computer security domain which have direct impact on everyday life. The first extends false data injection attacks against state estimation in electric power grids and then provides a novel power flow model camouflage method to hamper these attacks. The second deals with automotive theft response, detailing a method for a car to intelligently identify when it has been stolen, based on collected behavioral traits of its driver. The third demonstrates a new attack against the content integrity of the PDF file format, caus- ing humans and computers to see different information …


Towards Fundamental Understanding Of Thermoelectric Properties In Novel Materials Using First Principles Simulations, Artem R. Khabibullin Jun 2018

Towards Fundamental Understanding Of Thermoelectric Properties In Novel Materials Using First Principles Simulations, Artem R. Khabibullin

USF Tampa Graduate Theses and Dissertations

Thermoelectric materials play an important role in energy conversion as they represent environmentally safe and solid state devices with a great potential towards enhancing their efficiency. The ability to generate electric power in a reliable way without using non-renewable resources motivates many experimentalists as well as computational physicists to search and design new thermoelectric materials. Several classes of materials have been identified as good candidates for high efficient thermoelectrics because of their inherently low thermal conductivity. The complex study of the crystal and electronic structures of such materials helps to reveal hidden properties and give fundamental understanding, necessary for the …


Orientation Invariance Methods For Inertial Gait, Ravichandran Subramanian Jun 2018

Orientation Invariance Methods For Inertial Gait, Ravichandran Subramanian

USF Tampa Graduate Theses and Dissertations

Intelligent devices such as smart phones, smart watches, virtual reality (VR) headsets and personal exercise devices have become integral elements of accessories used by many people. The ability of these devices to verify or identify the user could be applied for enhanced security and user experience customization among other things. Almost all these devices have built-in inertial sensors such as accelerometer and gyroscope. These inertial sensors respond to the movements made by the user while performing day to day activities like walking, getting up and sitting down. The response depends on the activity being performed and thus can be used …


Assessing Bald Cypress (Taxodium Distichum) Tree Dynamic Change In Usf Forest Preserve Area Using Mixture-Tuned Matched Filtering And Multitemporal Satellite Imagery, Yujia Wang Jun 2018

Assessing Bald Cypress (Taxodium Distichum) Tree Dynamic Change In Usf Forest Preserve Area Using Mixture-Tuned Matched Filtering And Multitemporal Satellite Imagery, Yujia Wang

USF Tampa Graduate Theses and Dissertations

Wetlands are the most important and valuable ecosystems on Earth. They are called “kidneys of the Earth”. Vegetation change detection is necessary to understand the condition of a wetland and to support ecosystem sustainable management and utilization. It has been a great challenge to estimate vegetation (including bald cypress trees) coverage of the wetland because it is difficult to access directly. Satellite remote sensing technology can be one important feasible method to map and monitor changes of wetland forest vegetation and land cover over large areas. Remote sensing mapping techniques have been applied to detect and map vegetation changes in …


Comparison Of Beach Changes Induced By Two Hurricanes Along The Coast Of West-Central Florida, Ruoshu Zhao Jun 2018

Comparison Of Beach Changes Induced By Two Hurricanes Along The Coast Of West-Central Florida, Ruoshu Zhao

USF Tampa Graduate Theses and Dissertations

The beach profiles pre-and post-the Hurricane Hermine (2016) and Irma (2017) along the Sand Key barrier island were collected to quantify longshore variations in storm induced beach changes as well as to compare the beach changes caused by hydrodynamic conditions of the two different hurricanes.

Cross-shore beach profile are examined in 4 sections including dune field, dry beach, sand bar and whole beach to calculate beach change. The volume change for each section and shoreline contour change before and post the hurricane was computed. Hydrodynamic conditions were obtained from adjacent NOAA’s tide and wave gauges.

Both hurricanes generated high offshore …


Particles In Welding Fumes, Rebecca T. Williams Jun 2018

Particles In Welding Fumes, Rebecca T. Williams

USF Tampa Graduate Theses and Dissertations

The purpose of this study was to investigate whether or not differing base metals and filler wires used during welding processes contributed to differing amounts of ultrafine particles (UFP) and nanoparticles being emitted during the welding procedure. The study was also conducted to determine UFP and nanoparticle exposure in the breathing zones of the welders as well as the breathing zones of pipefitters and fire watchers, who commonly sit 6ft behind the welding arc. In order to determine if UFP and NP exposures differed with base metal and filler wire, all welding processes utilized the same welding machine for metal …


Biosorption Of Cobalt By Using Pseudomonas Aerguinosa Bacterial Strain, Abhaysinh Arvind Dharanguttikar Jun 2018

Biosorption Of Cobalt By Using Pseudomonas Aerguinosa Bacterial Strain, Abhaysinh Arvind Dharanguttikar

USF Tampa Graduate Theses and Dissertations

A study of biosorption of cobalt metal by Pseudomonas Aerguinosa gram-negative bacterial strain is presented. The present study is carried out to determine the optimum conditions of cobalt biosorption at ultra-low concentration (ppb range) in aqueous solutions. The receptiveness of cobalt metal on the extracellular surface of bacterial strain was examined by varying the pH, Initial concentration of metal and treatment time. Experimental data showed that effect of pH and treatment time is prevalent in biosorption of cobalt and by increasing both these parameters resulted in the efficient sorption of cobalt on the extracellular surface of Pseudomonas Aerguinosa. In some …


A Quantitative Analysis Of Shape Characteristics Of Marine Snow Particles With Interactive Visualization: Validation Of Assumptions In Coagulation Models, Palak P. Dave Jun 2018

A Quantitative Analysis Of Shape Characteristics Of Marine Snow Particles With Interactive Visualization: Validation Of Assumptions In Coagulation Models, Palak P. Dave

USF Tampa Graduate Theses and Dissertations

The Deepwater Horizon oil spill that started on April 20, 2010, in the Gulf of Mexico was the largest marine oil spill in the history of the petroleum industry. There was an unexpected and prolonged sedimentation event of oil-associated marine snow to the seafloor due to the oil spill. The sedimentation event occurred because of the coagulation process among oil associated marine particles. Marine scientists are developing models for the coagulation process of marine particles and oil, in order to estimate the amount of oil that may reach the seafloor along with marine particles. These models, used certain assumptions regarding …


Chemical Investigation Of Bioactive Marine Extracts, Selam Hagos Jun 2018

Chemical Investigation Of Bioactive Marine Extracts, Selam Hagos

USF Tampa Graduate Theses and Dissertations

Natural products have been a fundamental source of medicinal scaffolds for decades; with sixty percent of marketed drugs. Many synthetic chemists are focused on synthesizing potent and nontoxic compounds for pharmaceutical targets, however, nature is still proving to be a source of new bioactive compounds. Produced by the host organism for defense, reproduction and communication, secondary metabolites also demonstrate promising bioactivity against human pathogens. Hence, natural product chemists continue their quest for new leads.

As a continuation of these efforts, this thesis attempts to explore fungi and sponges for new chemistry, and ultimately, new drug candidates. Antarctica is largely untapped; …


A Comparative Study On Coastal Zone Changes And Anthropogenic Impacts Between Tampa Bay, Usa, And Xiangshan Harbor, China, During The Last 30 Years, Qiandong Guo Jun 2018

A Comparative Study On Coastal Zone Changes And Anthropogenic Impacts Between Tampa Bay, Usa, And Xiangshan Harbor, China, During The Last 30 Years, Qiandong Guo

USF Tampa Graduate Theses and Dissertations

Currently, the U.S. and China are the two largest national economic entities in the world. However, it is noticeable that the two countries have considerably different strategies for economic development, environmental protection and land supply in coastal zones. In order to understand the coastline dynamics, land use land cover (LULC) changes and land management policies in the U.S. and China, a case study of the Tampa Bay (TB) watershed, Florida, U.S., and Xiangshan Harbor (XH), Zhejiang Province, China was conducted. The two areas possess similar humid subtropical climate and dense population, but experienced different anthropogenic impacts. TB sat at a …


An Evaluation Of Marsh Shoreline Erosion And Sediment Deposition In The Grand Bay National Estuarine Research Reserve, Mississippi, Usa, Joseph Terrano Jun 2018

An Evaluation Of Marsh Shoreline Erosion And Sediment Deposition In The Grand Bay National Estuarine Research Reserve, Mississippi, Usa, Joseph Terrano

USF Tampa Graduate Theses and Dissertations

Coastal marshes serve important ecologic and economic functions, such as providing habitat, absorbing floodwaters and storm surges, and sequestering carbon. Throughout the northern Gulf of Mexico, coastal marshes are disappearing due to wave attack, sea-level rise, sediment export, and subsidence. Marsh area increases when sediments accumulate at the marsh shoreline, accrete vertically, and when non-marsh areas are colonized by marsh vegetation. Marsh shoreline erosion results in net marsh loss when transgression rates at the marsh-water edge exceed upland-marsh migration. The balance between marsh destroying and marsh creating processes determines the long-term survivability of a marsh system. Thus, processes of shoreline …


Diversity Of Ssdna Phages Related To The Family Microviridae Within The Ciona Robusta Gut, Alexandria Creasy Jun 2018

Diversity Of Ssdna Phages Related To The Family Microviridae Within The Ciona Robusta Gut, Alexandria Creasy

USF Tampa Graduate Theses and Dissertations

The gut microbiome is a complex ecosystem of bacteria, viruses, and fungi that strongly influences animal health. The bacterial component, for example, contributes orders of magnitude more gene products to host physiology than the host genome; thus, changes to the composition of these bacterial communities can have profound influences on the health of the animal. By infecting and lysing their hosts, viruses (particularly viruses infecting bacteria or phages) can affect critical functions in these environments, yet the consequences of these infections remain to be fully described. Most studies investigating gut viromes to date have focused on double-stranded DNA (dsDNA) phages …


Environmental Controls On The Geochemistry Of Globorotalia Truncatulinoides In The Gulf Of Mexico: Implications For Paleoceanographic Reconstructions, Caitlin Elizabeth Reynolds Jun 2018

Environmental Controls On The Geochemistry Of Globorotalia Truncatulinoides In The Gulf Of Mexico: Implications For Paleoceanographic Reconstructions, Caitlin Elizabeth Reynolds

USF Tampa Graduate Theses and Dissertations

Modern observations of planktic foraminifera from sediment trap studies help to constrain the regional ecology of paleoceanographically valuable species. Results from a weekly-resolved sediment trap time series (2008–2014) in the northern Gulf of Mexico demonstrate that 92% of Globorotalia truncatulinoides flux occurs in winter (January, February, and March), and that encrusted and non-encrusted individuals represent calcification in distinct depth habitats. We use individual foraminiferal analysis (IFA) of G. truncatulinoides tests to investigate differences in the elemental (Mg/Ca) and isotopic composition (18O and 13C) of the encrusted and non-encrusted ontogenetic forms of G. truncatulinoides, and to estimate their calcification depth in …


Channel Camouflage And Manipulation Techniques In Wireless Networks, Song Fang Jun 2018

Channel Camouflage And Manipulation Techniques In Wireless Networks, Song Fang

USF Tampa Graduate Theses and Dissertations

The security of wireless networks and systems is becoming increasingly important as wireless devices are more and more ubiquitous nowadays. The wireless channel exhibits the spatial uncorrelation property, which is that the characteristics of a wireless channel become uncorrelated every half carrier wavelength over distance. This property has prompted an emerging research area that utilizes wireless channel characteristics to achieve location distinction, to detect location changes or facilitate authentication of wireless users, and to establish shared secret key between legitimate communicators. This dissertation includes two work toward the security improvement of existing wireless networks and systems. With the discovered channel …


Surface And Interface Effects Of Magnetoimpedance Materials At High Frequency, Tatiana M. Eggers Jun 2018

Surface And Interface Effects Of Magnetoimpedance Materials At High Frequency, Tatiana M. Eggers

USF Tampa Graduate Theses and Dissertations

Amorphous and nanocrystalline transition metal magnetic alloys (TMMAs) have been the subjects of fundamental and applied study due to their unique structure. The lack of long-range order in these materials sets the stage for their soft magnetic properties to be tuned for a variety of technological applications, such as sensitive magnetic field sensors, high frequency transformers, and stress sensors. Fundamental investigation of the magnetic and structural properties of these materials is also motivated by their unique amorphous or nanocrystalline-embedded amorphous matrix morphology, which has consequences on both the magnetism seen from both the atomic and macro-scale. The surfaces of these …


Determining Level Of Cognitive Impairment Via Computing Fractals Using A Computer, Kodhanda Karthik Siriyala Jun 2018

Determining Level Of Cognitive Impairment Via Computing Fractals Using A Computer, Kodhanda Karthik Siriyala

USF Tampa Graduate Theses and Dissertations

Mild Cognitive Impairment is a condition that affects an individual's thinking and decision making capabilities. Specifically, it is one where an individual's capabilities of memorizing, thinking and decision making are less efficient when compared to others. In order to diagnose this condition, a conventional method is to provide the subject with a small challenge they should be completed using pen and paper. This thesis focuses on how this method can be converted to a computer based test. A data visualization tool named Processing has been used to develop a system that runs a game-like test, which is completed by individuals …