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Full-Text Articles in Physical Sciences and Mathematics

Environmental And Energy Saving Technologies Of Vinyl Chloride Production, Mykola Kurta Feb 2013

Environmental And Energy Saving Technologies Of Vinyl Chloride Production, Mykola Kurta

USF Tampa Graduate Theses and Dissertations

Recently, because of the increase of environmental concerns in process design, the need to enhance conversion to product and prevent generation of wasteful byproducts in the reactor network has become urgent. This prevents high cost treatment and separation costs downstream in the process. Therefore, in this thesis I focus on making production of vinyl chloride monomer (VCM) more efficient and on possible ways of industrial organochlorine waste (OCW) recycling. In particular, in the first experiment, we investigate how catalyst and its structure can affect product output.

Infrared spectroscopy and X-ray diffraction analysis were utilized to investigate the structure of the …


Location And Capacity Modeling Of Network Interchanges, Aldo D. Fabregas Feb 2013

Location And Capacity Modeling Of Network Interchanges, Aldo D. Fabregas

USF Tampa Graduate Theses and Dissertations

Network design decisions, especially those pertaining to urban infrastructure, are made by a central authority or network leader, and taking into consideration the network users or followers. These network decision problems are formulated as non-linear bi-level programming problems. In this work, a continuous network design problem (CNDP) and discrete network design problem (DNDP) bi-level optimization programs are proposed and solved in the context of transportation planning. The solution strategy involved reformulation and linearization as a single-level program by introducing the optimality conditions of the lower level problem into the upper level problem. For the CNDP, an alternative linearization algorithm (modified …


Uncontrolled Hypertension And Associated Factors In Hypertensive Patients At The Primary Healthcare Center Luis H. Moreno, Panama: A Feasibility Study, Roderick Ramon Chen Camano Jan 2013

Uncontrolled Hypertension And Associated Factors In Hypertensive Patients At The Primary Healthcare Center Luis H. Moreno, Panama: A Feasibility Study, Roderick Ramon Chen Camano

USF Tampa Graduate Theses and Dissertations

Background: According to the World Health Organization (WHO), hypertension is a major risk factor for cardiovascular disease (CVD), renal impairment, peripheral vascular disease, and blindness. In Panama, a recent study estimated the prevalence of hypertension at 38.5% in the two main provinces of the country, with a rate of uncontrolled hypertension of 47.2%.

Objectives: The aims of this study were to assess the feasibility of the study design and to describe the characteristics of the hypertensive population and the physician's adherence to Panamanian antihypertensive protocols and their relationship with uncontrolled hypertension.

Methods: This is a cross-sectional study of adult hypertensive …


Virtual Screening For Inhibitors Of Anti-Apoptotic Proteins: Dck, Bcl-Xl, Mcl-1, Mdmx, And Mdm2, Courtney Jerome Du Boulay Jan 2013

Virtual Screening For Inhibitors Of Anti-Apoptotic Proteins: Dck, Bcl-Xl, Mcl-1, Mdmx, And Mdm2, Courtney Jerome Du Boulay

USF Tampa Graduate Theses and Dissertations

←Within this dissertation the topic of virtual screening is discussed with regard to three different cancer targets and also a brief introduction of the tools used in virtual screening. In Chapter 1, the reader will be introduced to virtual screening and the programs that are used in virtual screening. In Chapter 2, the first of three projects are discussed. This project consists of the work that was done to find inhibitors of the P53 binding domain of MDMX. In this project the mobility of residues within the binding site of MDMX are discussed and the ways in which we attempted …


Analytic Functions With Real Boundary Values In Smirnov Classes EP, Lisa De Castro Jan 2013

Analytic Functions With Real Boundary Values In Smirnov Classes EP, Lisa De Castro

USF Tampa Graduate Theses and Dissertations

This thesis concerns the classes of analytic functions on bounded, n-connected domains known as the Smirnov classes Ep, where p > 0. Functions in these classes satisfy a certain growth condition and have a relationship to the more well known classes of functions known as the Hardy classes Hp. In this thesis I will show how the geometry of a given domain will determine the existence of non-constant analytic functions in Smirnov classes that possess real boundary values. This is a phenomenon that does not occur among functions in the Hardy classes.

The preliminary and background information …


The Spectrophotometric Analysis Of Lead Carbonate Complexation And Carbonate Saturation States In Seawater, Regina Anita Easley Jan 2013

The Spectrophotometric Analysis Of Lead Carbonate Complexation And Carbonate Saturation States In Seawater, Regina Anita Easley

USF Tampa Graduate Theses and Dissertations

The carbon dioxide (CO2) system is the primary buffer in seawater which controls oceanic pH. Changes in the marine CO2 system affect a number of processes such as metal speciation, mineral saturation states, auditory responses in fish, and primary productivity rates. Increased atmospheric concentrations of CO2 from human activities (e.g. burning of fossil fuels, deforestation, and cement production) has led to a global decrease in surface ocean pH termed anthropogenic ocean acidification. One particular concern in response to increased oceanic CO2 is a substantial decrease in the calcium carbonate (CaCO3) saturation states, Ω …


The Water Culture Beliefs Of Embera Communities And Maternal And Child Health In The Republic Of Panama, Ilenia Anneth Forero Jan 2013

The Water Culture Beliefs Of Embera Communities And Maternal And Child Health In The Republic Of Panama, Ilenia Anneth Forero

USF Tampa Graduate Theses and Dissertations

Water has cultural and spiritual values to indigenous people. These beliefs expose them to unsafe water sources and make them vulnerable to waterborne diseases. This background is not taken into account when countries write their water legislations, therefor imposing a management of water not readily accepted by them. The Embera group is one of the indigenous groups from the Republic of Panama, who have strong water beliefs. They live along the shore of rivers in houses built on high stilts away from urban areas. The purpose of this cross-sectional community based study is to describe through a survey the relation …


Hearing And Echolocation In Stranded And Captive Odontocete Cetaceans, Danielle Greenhow Jan 2013

Hearing And Echolocation In Stranded And Captive Odontocete Cetaceans, Danielle Greenhow

USF Tampa Graduate Theses and Dissertations

Odontocetes use echolocation to detect, track, and discriminate their prey, as well as negotiate their environment. Their hearing abilities match the frequency of greatest sensitivity to the higher frequencies used for foraging and navigation. Hearing and echolocation together provide odontocetes with a highly developed biosonar system. This dissertation examines the hearing ability of several odontocete species to understand what signals they can perceive during echolocation. The variability in hearing ranges between species is examined in the context of phylogenetic and ecological differences among taxa. An autonomous hydrophone array is also developed that could be used in an expanded form in …


Multiple Calibrations In Integrative Data Analysis: A Simulation Study And Application To Multidimensional Family Therapy, Kristin Wynn Hall Jan 2013

Multiple Calibrations In Integrative Data Analysis: A Simulation Study And Application To Multidimensional Family Therapy, Kristin Wynn Hall

USF Tampa Graduate Theses and Dissertations

A recent advancement in statistical methodology, Integrative Data Analyses (IDA Curran & Hussong, 2009) has led researchers to employ a calibration technique as to not violate an independence assumption. This technique uses a randomly selected, simplified correlational structured subset, or calibration, of a whole data set in a preliminary stage of analysis. However, a single calibration estimator suffers from instability, low precision and loss of power. To overcome this limitation, a multiple calibration (MC; Greenbaum et al., 2013; Wang et al., 2013) approach has been developed to produce better estimators, while still removing a level of dependency in the data …


A Latent Mixture Approach To Modeling Zero-Inflated Bivariate Ordinal Data, Rajendra Kadel Jan 2013

A Latent Mixture Approach To Modeling Zero-Inflated Bivariate Ordinal Data, Rajendra Kadel

USF Tampa Graduate Theses and Dissertations

Multivariate ordinal response data, such as severity of pain, degree of disability, and satisfaction with a healthcare provider, are prevalent in many areas of research including public health, biomedical, and social science research. Ignoring the multivariate features of the response variables, that is, by not taking the correlation between the errors across models into account, may lead to substantially biased estimates and inference. In addition, such multivariate ordinal outcomes frequently exhibit a high percentage of zeros (zero inflation) at the lower end of the ordinal scales, as compared to what is expected under a multivariate ordinal distribution. Thus, zero inflation …


Optimized Correlation Of Geophysical And Geotechnical Methods In Sinkhole Investigations: Emphasizing On Spatial Variations In West-Central Florida, Henok Gidey Kiflu Jan 2013

Optimized Correlation Of Geophysical And Geotechnical Methods In Sinkhole Investigations: Emphasizing On Spatial Variations In West-Central Florida, Henok Gidey Kiflu

USF Tampa Graduate Theses and Dissertations

Abstract

Sinkholes and sinkhole-related features in West-Central Florida (WCF) are commonly identified using geotechnical investigations such as standard penetration test (SPT) borings and geophysical methods such as ground penetrating radar (GPR) and electrical resistivity tomography (ERT). Geophysical investigation results can be used to locate drilling and field testing sites while geotechnical investigation can be used to ground truth geophysical results. Both methods can yield complementary information. Geotechnical investigations give important information about the type of soil, groundwater level and presence of low-density soils or voids at the test location, while geophysical investigations like GPR surveys have better spatial coverage and …


Argumentation As A Lens To Examine Student Discourse In Peer-Led Guided Inquiry For College General Chemistry, Ushiri Kumarihamy Kulatunga Jan 2013

Argumentation As A Lens To Examine Student Discourse In Peer-Led Guided Inquiry For College General Chemistry, Ushiri Kumarihamy Kulatunga

USF Tampa Graduate Theses and Dissertations

This dissertation work entails three related studies on the investigation of Peer-Led Guided Inquiry student discourse in a General Chemistry I course through argumentation. The first study, Argumentation and participation patterns in general chemistry peer-led sessions, is focused on examining arguments and participation patterns in small student groups without peer leader intervention. The findings of this study revealed that students were mostly engaged in co-constructed arguments, that a discrepancy in the participation of the group members existed, and students were able to correct most of the incorrect claims on their own via argumentation.

The second study, Exploration of peer leader …


Delta Encoding Based Methods To Reduce The Size Of Smartphone Application Updates, Nikolai Samteladze Jan 2013

Delta Encoding Based Methods To Reduce The Size Of Smartphone Application Updates, Nikolai Samteladze

USF Tampa Graduate Theses and Dissertations

In 2012 the two biggest smartphone application markets - the Google Play store and the Apple App Store - each had close to 700 thousand applications with approximately 2 billion downloads happening every month. The introduction of new features and correction of bugs and security vulnerabilities make it usual for mobile application developers to release new version of an application every month. Combined with the great smartphone popularity, it leads to approximately 400 PB annual traffic generated by app updates in the U.S. wireless networks alone. Being partially transmitted through cellular networks, mobile application updates traffic accounts to up to …


Consumer Acceptance Of Mobile Payments In Restaurants, Anna Shatskikh Jan 2013

Consumer Acceptance Of Mobile Payments In Restaurants, Anna Shatskikh

USF Tampa Graduate Theses and Dissertations

Regardless all the advantages of MPs, it has not reach the sizable customer base. In this paper, we examined the core drivers of using mobile payments (MPs) in restaurant industry from the consumers' perspective. Based on the Technology Acceptance Model (TAM), we developed a six factor model to reveal the determinants of consumers' intention to use MPs in restaurant. Security, subjective norm, compatibility with lifestyle, and previous experience with MPs were added to the traditional two factor TAM model (usefulness and ease of use). 300 respondents were recruited from an online survey agency and 258 valid responses were included in …


Turning Water Into Wine: The Political Economy Of The Environment In Southern California's Wine Country, Jason Simms Jan 2013

Turning Water Into Wine: The Political Economy Of The Environment In Southern California's Wine Country, Jason Simms

USF Tampa Graduate Theses and Dissertations

This dissertation examines questions of water sustainability in contexts of wine production and state-led neoliberal development in the Temecula Valley, southern California, where wine tourism is at present being harnessed as an engine of economic growth. Natural and anthropogenic forces, such as global climate change, desertification, urban development, and the marketization and commodification of natural resources, affect the distribution and availability of water throughout the globe. As a result, the use of water, and associated political and environmental processes and consequences, in the production of global commodities, including wheat, citrus, and coffee, recently have come under increased scrutiny. Given wine's …


Robotic Swarming Without Inter-Agent Communication, Daniel Jonathan Standish Jan 2013

Robotic Swarming Without Inter-Agent Communication, Daniel Jonathan Standish

USF Tampa Graduate Theses and Dissertations

Many physical and algorithmic swarms utilize inter-agent communication to achieve advanced swarming behaviors. These swarms are inspired by biological swarms that can be seen throughout nature and include bee swarms, ant colonies, fish schools, and bird flocks. These biological swarms do not utilize inter-agent communication like their physical and algorithmic counterparts. Instead, organisms in nature rely on a local awareness of other swarm members that facilitates proper swarm motion and behavior. This research aims to pursue an effective swarm algorithm using only line-of-sight proximity information and no inter-agent communication. It is expected that the swarm performance will be lower than …


Non-Equilibrium Melting And Sublimation Of Graphene Simulated With Two Interatomic Potentials, Brad Steele Jan 2013

Non-Equilibrium Melting And Sublimation Of Graphene Simulated With Two Interatomic Potentials, Brad Steele

USF Tampa Graduate Theses and Dissertations

The mechanisms of the sublimation of graphene at zero pressure and the condensation of carbon vapor is investigated by molecular dynamics (MD) simulations. The interatomic interactions are described by the Reactive Empirical Bond Order potential (REBO). It is found that graphene sublimates at a temperature of 5,200 K. At the onset of sublimation, defects that contain several pentagons and heptagons are formed, that are shown to evolve from double vacancies and stone wales defects. These defects consisting of pentagons and heptagons act as nucleation sites for the gaseous phase. The influence of the interatomic interactions on the sublimation process are …


Synthesis And Properties Of Polymer Nanocomposites With Tunable Electromagnetic Response, Kristen Lee Stojak Jan 2013

Synthesis And Properties Of Polymer Nanocomposites With Tunable Electromagnetic Response, Kristen Lee Stojak

USF Tampa Graduate Theses and Dissertations

Multifunctional polymer nanocomposites (PNCs) are attractive for the design of tunable RF and microwave components such as flexible electronics, attenuators, and antennas due to cost-effectiveness and durability of polymeric matrices. In this work, three separate PNCs were synthesized. Magnetite (Fe3O4) and cobalt ferrite (CFO) nanoparticles, synthesized by thermal decomposition, were used as PNC fillers. Polymers used in this work were a commercial polymer provided by the Rogers Corporation (RP) and polyvinylidene fluoride (PVDF). PNCs in this thesis consist of Fe3O4 in RP, CFO in RP, and Fe3O4 in PVDF. Characterization techniques for determining morphology of the nanoparticles, and their resulting …


Investigations For Utilizing Pteropods As Bioindicators Of Environmental Change Along The Western Antarctic Peninsula, Paul Mark Suprenand Jan 2013

Investigations For Utilizing Pteropods As Bioindicators Of Environmental Change Along The Western Antarctic Peninsula, Paul Mark Suprenand

USF Tampa Graduate Theses and Dissertations

Pteropods are holoplanktonic gastropod molluscs found globally. Although species diversity is greater at lower latitudes, species abundance is greater at temperate and polar latitudes. Declines in pteropod populations have not only been correlated to declines of their major predators, but pteropods have also been used as bioindicators of global environmental changes such as ocean acidification. With high latitude abundances, pteropods provide significant sustenance for species such as the Atlantic salmon in the Atlantic Ocean and Pleuragramma antarcticum in the Southern Ocean. Because pteropods eat phytoplankton and other pteropods, factors that affect pteropod abundance influence many trophic levels. This dissertation explores …


Asymmetric Nitrene Transfer Reactions With Azides Via Co(Ii)-Based Metalloradical Catalysis (Mrc), Jingran Tao Jan 2013

Asymmetric Nitrene Transfer Reactions With Azides Via Co(Ii)-Based Metalloradical Catalysis (Mrc), Jingran Tao

USF Tampa Graduate Theses and Dissertations

Asymmetric nitrene transfer reactions via metalloradical catalysis (MRC) with

azides has attracted research interest because of its fundamental and practical importance.

The resulting nitrogen-containing units are recurrent motifs in biologically important

molecules and can serve as versatile precursors in organic synthesis.

The [Co(D2-Por*)] have emerged as a new class of catalysts for asymmetric

aziridination and C-H amination. These metalloradical catalysts have been shown to be

highly effective for the asymmetric intermolecular aziridination of a broad scope of

substrates with different classes of azides with excellent to good enantioselectivity. The

intramolecular C-H amination utilizing various azides can allow for the construction …


Automatic Identification Of Points Of Interest In Global Navigation Satellite System Data: A Spatial Temporal Approach, Khoa Anh Tran Jan 2013

Automatic Identification Of Points Of Interest In Global Navigation Satellite System Data: A Spatial Temporal Approach, Khoa Anh Tran

USF Tampa Graduate Theses and Dissertations

In addition to the emergence of smartphones and tablets in recent years, the rise of Global Navigation Satellite Systems (GNSS) has allowed mobile tracking applications to become popular and be put into many uses. Analyzing tracking records to identify points of interest (POIs) is useful for both prediction applications and research such as human behavior analysis, transportation planning, and especially travel surveys. Past research in travel surveys has shown that a GPS mobile phone-based survey is a useful tool for collecting information about individuals. Moreover, a passive travel survey collection is preferred to an active travel survey method by the …


Boolean Partition Algebras, Joseph Anthony Van Name Jan 2013

Boolean Partition Algebras, Joseph Anthony Van Name

USF Tampa Graduate Theses and Dissertations

A Boolean partition algebra is a pair $(B,F)$ where $B$ is a Boolean

algebra and $F$ is a filter on the semilattice of partitions of $B$ where $\bigcup F=B\setminus\{0\}$. In this dissertation, we shall investigate the algebraic theory of Boolean partition algebras and their connection with uniform spaces. In particular, we shall show that the category of complete non-Archimedean uniform spaces

is equivalent to a subcategory of the category of Boolean partition algebras, and notions such as supercompleteness

of non-Archimedean uniform spaces can be formulated in terms of Boolean partition algebras.


Flexible Urban Water Distribution Systems, Seneshaw Amare Tsegaye Jan 2013

Flexible Urban Water Distribution Systems, Seneshaw Amare Tsegaye

USF Tampa Graduate Theses and Dissertations

With increasing global change pressures such as urbanization and climate change, cities of the future will experience difficulties in efficiently managing scarcer and less reliable water resources. However, projections of future global change pressures are plagued with uncertainties. This increases the difficulty in developing urban water systems that are adaptable to future uncertainty.

A major component of an urban water system is the distribution system, which constitutes approximately 80-85% of the total cost of the water supply system (Swamee and Sharma, 2008). Traditionally, water distribution systems (WDS) are designed using deterministic assumptions of main model input variables such as water …


Computational Approaches For Structure Based Drug Design And Protein Structure-Function Prediction, Sai Lakshmana Kumar Vankayala Jan 2013

Computational Approaches For Structure Based Drug Design And Protein Structure-Function Prediction, Sai Lakshmana Kumar Vankayala

USF Tampa Graduate Theses and Dissertations

This dissertation thesis consists of a series of chapters that are interwoven by solving interesting biological problems, employing various computational methodologies. These techniques provide meaningful physical insights to promote the scientific fields of interest. Focus of chapter 1 concerns, the importance of computational tools like docking studies in advancing structure based drug design processes. This chapter also addresses the prime concerns like scoring functions, sampling algorithms and flexible docking studies that hamper the docking successes. Information about the different kinds of flexible dockings in terms of accuracy, time limitations and success studies are presented. Later the importance of Induced fit …


Assessing Hurricane Preparedness Among Residential Staff At Louisiana State University: A Case Study On Hurricane Isaac, Ashley Marie Weatherall Jan 2013

Assessing Hurricane Preparedness Among Residential Staff At Louisiana State University: A Case Study On Hurricane Isaac, Ashley Marie Weatherall

USF Tampa Graduate Theses and Dissertations

Studying hurricane preparedness among the Resident Assistants (RAs) and Residence Life Coordinators (RLCs) at Louisiana State University (LSU) is imperative to assure that the university housing staff is fully equipped when faced with an oncoming threat. This study seeks to fill a gap in research by investigating the influences of preparedness on student housing employees. A survey was developed and the measures were found to be coherent and internally reliable through the use of factor analysis. Based on theory and previous literature, a linear regression model was developed that quantified the relationship between the independent variable of preparedness and general …


An Application Developed For Simulation Of Electrical Excitation And Conduction In A 3d Human Heart, Di Yu Jan 2013

An Application Developed For Simulation Of Electrical Excitation And Conduction In A 3d Human Heart, Di Yu

USF Tampa Graduate Theses and Dissertations

This thesis first reviews the history of General Purpose computing Graphic Processing Unit (GPGPU) and then introduces the fundamental problems that are suitable for GPGPU algorithm. The architecture of GPGPU is compared against modern CPU architecture, and the fundamental difference is outlined. The programming challenges faced by GPGPU and the techniques utilized to overcome these issues are evaluated and discussed.

The second part of the thesis presents an application developed with GPGPU technology to simulate the electrical excitation and conduction in a 3D human heart model based on cellular automata model. The algorithm and implementation are discussed in detail and …


Algorithms And Data Structures For Efficient Timing Analysis Of Asynchronous Real-Time Systems, Yingying Zhang Jan 2013

Algorithms And Data Structures For Efficient Timing Analysis Of Asynchronous Real-Time Systems, Yingying Zhang

USF Tampa Graduate Theses and Dissertations

This thesis presents a framework to verify asynchronous real-time systems based on model checking. These systems are modeled by using a common modeling formalism named Labeled Petri-nets(LPNs).

In order to verify the real-time systems algorithmically, the zone-based timing analysis method is used for LPNs. It searches the state space with timing information (represented by zones). When there is a high degree of concurrency in the model, firing concurrent enabled transitions in different order may result in different zones, and these zones may be combined without affecting the verification result. Since the zone-based method could not deal with this problem efficiently, …


Statistical Topics Applied To Pressure And Temperature Readings In The Gulf Of Mexico, Malena Kathleen Allison Jan 2013

Statistical Topics Applied To Pressure And Temperature Readings In The Gulf Of Mexico, Malena Kathleen Allison

USF Tampa Graduate Theses and Dissertations

The field of statistical research in weather allows for the application of old and new methods, some of which may describe relationships between certain variables better such as temperatures and pressure. The objective of this study was to apply a variety of traditional and novel statistical methods to analyze data from the National Data Buoy Center, which records among other variables barometric pressure, atmospheric temperature, water temperature and dew point temperature. The analysis included attempts to better describe and model the data as well as to make estimations for certain variables. The following statistical methods were utilized: linear regression, non-response …


Exploring Local Food System Practices And Perceptions: Insights From Florida's Snap-Authorized Farmers' Markets, Leslie Babiak Jan 2013

Exploring Local Food System Practices And Perceptions: Insights From Florida's Snap-Authorized Farmers' Markets, Leslie Babiak

USF Tampa Graduate Theses and Dissertations

Despite heightened interest in creating local food systems that enhance health of ecologies, economies, and all members of communities, the public space of farmers' markets is far less than inherently equitable. This is particularly concerning given America's unprecedented crisis of food hardship and related disease, which disproportionately affects lower income populations. This research addresses the social justice implications of SNAP (food stamp) operations for locally oriented food systems. Pioneering practices of three of Florida's SNAP-authorized farmers' markets, and the attitudes and behaviors of one-hundred-seventy-six market patrons, were explored through customer surveys, market manager interviews, and environmental assessments. Qualitative and quantitative …


Effectiveness Of Propensity Score Methods In A Multilevel Framework: A Monte Carlo Study, Aarti P. Bellara Jan 2013

Effectiveness Of Propensity Score Methods In A Multilevel Framework: A Monte Carlo Study, Aarti P. Bellara

USF Tampa Graduate Theses and Dissertations

Propensity score analysis has been used to minimize the selection bias in observational studies to identify causal relationships. A propensity score is an estimate of an individual's probability of being placed in a treatment group given a set of covariates. Propensity score analysis aims to use the estimate to create balanced groups, akin to a randomized experiment. This study used Monte Carlo methods to examine the appropriateness of using propensity score methods to achieve balance between groups on observed covariates and reproduce treatment effect estimates in multilevel studies. Specifically, this study examined the extent to which four different propensity score …