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USF Tampa Graduate Theses and Dissertations

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Full-Text Articles in Physical Sciences and Mathematics

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 …


Automatic Macro- And Micro-Facial Expression Spotting And Applications, Matthew Adam Shreve Jan 2013

Automatic Macro- And Micro-Facial Expression Spotting And Applications, Matthew Adam Shreve

USF Tampa Graduate Theses and Dissertations

Automatically determining the temporal characteristics of facial expressions has extensive application domains such as human-machine interfaces for emotion recognition, face identification, as well as medical analysis. However, many papers in the literature have not addressed the step of determining when such expressions occur. This dissertation is focused on the problem of automatically segmenting macro- and micro-expressions frames (or retrieving the expression intervals) in video sequences, without the need for training a model on a specific subset of such expressions. The proposed method exploits the non-rigid facial motion that occurs during facial expressions by modeling the strain observed during the elastic …


A Monte Carlo Approach To Change Point Detection In A Liver Transplant, Alexia Melissa Makris Jan 2013

A Monte Carlo Approach To Change Point Detection In A Liver Transplant, Alexia Melissa Makris

USF Tampa Graduate Theses and Dissertations

Patient survival post liver transplant (LT) is important to both the patient and the center's accreditation, but over the years physicians have noticed that distant patients struggle with post LT care. I hypothesized that patient's distance from the transplant center had a detrimental effect on post LT survival. I suspected Hepatitis C (HCV) and Hepatocellular Carcinoma (HCC) patients would deteriorate due to their recurrent disease and there is a need for close monitoring post LT. From the current literature it was not clear if patients' distance from a transplant center affects outcomes post LT. Firozvi et al. (Firozvi AA, 2008) …


Age Dependent Analysis And Modeling Of Prostate Cancer Data, Nana Osei Mensa Bonsu Jan 2013

Age Dependent Analysis And Modeling Of Prostate Cancer Data, Nana Osei Mensa Bonsu

USF Tampa Graduate Theses and Dissertations

Growth rate of prostate cancer tumor is an important aspect of understanding the natural history of prostate cancer. Using real prostate cancer data from the SEER database with tumor size as a response variable, we have clustered the cancerous tumor sizes into age groups to enhance its analytical behavior. The rate of change of the response variable as a function of age is given for each cluster. Residual analysis attests to the quality of the analytical model and the subject estimates. In addition, we have identified the probability distribution that characterize the behavior of the response variable and proceeded with …


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 …


Cultivating Local: Building A Local Food System In Western North Carolina, Allison S. Perrett Jan 2013

Cultivating Local: Building A Local Food System In Western North Carolina, Allison S. Perrett

USF Tampa Graduate Theses and Dissertations

This dissertation examines a movement in Western North Carolina to build a local food system, one grounded in the conditions and relationships of place. In 2000, Mountain Family Farms launched the Local Food Campaign to raise public awareness about the region's farms and farming heritage, to educate consumers about the benefits of buying food grown by local farms, and, ultimately, to build markets for locally grown food to sustain the region's farms. The campaign sparked a social movement and over a decade later local farms and locally grown food are a palpable feature of life in the mountains of Western …


Statistical Analysis And Modeling Of Prostate Cancer, Yiu Ming Chan Jan 2013

Statistical Analysis And Modeling Of Prostate Cancer, Yiu Ming Chan

USF Tampa Graduate Theses and Dissertations

The objective of the present study is to address some important questions related to prostate cancer treatments and survivorship among White and African American men. It is commonly understood that the risk of developing prostate cancer is higher in African American men than the other races. However, using parametric analysis, this study demonstrates that this perception is a "myth" not a "reality". The study further identifies the existence of racial/ethnic disparities by comparing the average mean tumor size, the median of survival time, and the survival function between White and African American men. These results underline the necessity of understanding …


Modeling Potential Chemical Environments: Implications For Astrobiology, Brian Craig Szenay Jan 2013

Modeling Potential Chemical Environments: Implications For Astrobiology, Brian Craig Szenay

USF Tampa Graduate Theses and Dissertations

Modeling chemical environments is an important step to understanding the diversity of prebiotic systems that may have formed on the early earth or potentially can occur on other worlds. By using the modern Earth as a test case, these models predict scenarios with systems more conducive to the formation of the organic molecules that are important to life. Here we use the equilibrium thermodynamic modeling program HSC Chem to investigate prebiotic environments. This program uses the raw material that the user inputs into the system in order to calculate the change in amounts of chemical species forming as a function …


Human Intention Recognition Based Assisted Telerobotic Grasping Of Objects In An Unstructured Environment, Karan Hariharan Khokar Jan 2013

Human Intention Recognition Based Assisted Telerobotic Grasping Of Objects In An Unstructured Environment, Karan Hariharan Khokar

USF Tampa Graduate Theses and Dissertations

In this dissertation work, a methodology is proposed to enable a robot to identify an object to be grasped and its intended grasp configuration while a human is teleoperating a robot towards the desired object. Based on the detected object and grasp configuration, the human is assisted in the teleoperation task. The environment is unstructured and consists of a number of objects, each with various possible grasp configurations. The identification of the object and the grasp configuration is carried out in real time, by recognizing the intention of the human motion. Simultaneously, the human user is assisted to preshape over …


Evaluating Habitat Vulnerability And Sustainability Of Urban Seagrass Resources To Sea Level Rise, Cynthia A. Meyer Jan 2013

Evaluating Habitat Vulnerability And Sustainability Of Urban Seagrass Resources To Sea Level Rise, Cynthia A. Meyer

USF Tampa Graduate Theses and Dissertations

The seagrass resource provides essential ecosystem functions for many marine species. This research evaluated the vulnerability and sustainability of the seagrass resource in an urbanized area to the effects of sea level rise. The assessment required analysis of information regarding the biogeography of the seagrass resource, and developing a method to model the spatial extent of the suitable habitat for seagrass, and applying the model to predict the implications of simulated sea level rise scenarios on the seagrass resource.

Examining the biogeography of the seagrass resource required the development of a seagrass monitoring and assessment field survey and a comprehensive …


Investigation Of Mercury Use, Release, Deposition, And Exposures In The Tampa Bay Area, Ryan Algernon Michael Jan 2013

Investigation Of Mercury Use, Release, Deposition, And Exposures In The Tampa Bay Area, Ryan Algernon Michael

USF Tampa Graduate Theses and Dissertations

I investigate the links between mercury use, release, deposition, and population exposure in Tampa Bay, with the focus of identifying levers for reducing population mercury exposures. To achieve this, I investigated the trends in mercury use and release by products and processes in the Tampa Bay area using a Material Flow Analysis. Analysis of USEPA National Emissions Inventory data over time (1999 - 2008) identified relevant air source emission categories, and explored and compared state and regional trends in mercury emissions. To understand source contributions to wet deposited mercury in the Tampa Bay area, I analyzed trends in mercury deposition …


Relative Survival Of Gags Mycteroperca Microlepis Released Within A Recreational Hook-And-Line Fishery: Application Of The Cox Regression Model To Control For Heterogeneity In A Large-Scale Mark-Recapture Study, Beverly J. Sauls Jan 2013

Relative Survival Of Gags Mycteroperca Microlepis Released Within A Recreational Hook-And-Line Fishery: Application Of The Cox Regression Model To Control For Heterogeneity In A Large-Scale Mark-Recapture Study, Beverly J. Sauls

USF Tampa Graduate Theses and Dissertations

The objectives of this study were to measure injuries and impairments directly observed from gags Mycteroperca microlepis caught and released within a large-scale recreational fishery, develop methods that may be used to rapidly assess the condition of reef fish discards, and estimate the total portion of discards in the fishery that suffer latent mortality. Fishery observers were placed on for-hire charter and headboat vessels operating in the Gulf of Mexico from June 2009 through December 2012 to directly observe reef fishes as they were caught by recreational anglers fishing with hook-and-line gear. Fish that were not retained by anglers were …


The Extent Of Phosporus Redox Chemistry In West Central Florida Waters, Jacqueline Marie Sampson Jan 2013

The Extent Of Phosporus Redox Chemistry In West Central Florida Waters, Jacqueline Marie Sampson

USF Tampa Graduate Theses and Dissertations

Phosphorus (P) has long been acknowledged as a vital nutrient for living organisms and is a key factor responsible for the fresh water eutrophication. Our understanding of the phosphorus cycle has been limited by: (1) the common assumption that all P in the environment occurs primarily as phosphates and (2) by the limited analytical methods available to identify P speciation. In an attempt to understand the distribution and chemistry of phosphorus within a freshwater system we must be able to identify individual P species. To this end, we used a coupled High Performance Liquid Chromatograph (HPLC) - Inductively Coupled Plasma …


Improving Implementation Of A Regional In-Line Chlorinator In Rural Panama Through Development Of A Regionally Appropriate Field Guide, Benjamin A. Yoakum Jan 2013

Improving Implementation Of A Regional In-Line Chlorinator In Rural Panama Through Development Of A Regionally Appropriate Field Guide, Benjamin A. Yoakum

USF Tampa Graduate Theses and Dissertations

Access to safe drinking water has a direct effect on improving human health and their quality of life. One country still struggling with providing access to safe drinking water to all of its population is Panama. Panama's largest indigenous group, the Ngöbe people, is disproportionately affected by lack of access to safe drinking water. One way Panama's Ministry of Health (MINSA) is attempting to increase access to safe drinking water to the Ngöbe people is by disinfecting the water already captured by rural gravity fed water systems constructed within in the Ngöbe-Bugle reservation. This is accomplished using an in-line chlorinator …


Novel Models And Algorithms For Uncertainty Management In Power Systems, Long Zhao Jan 2013

Novel Models And Algorithms For Uncertainty Management In Power Systems, Long Zhao

USF Tampa Graduate Theses and Dissertations

This dissertation is a collection of previously-published manuscript and conference papers. In this dissertation, we will deal with a stochastic unit commitment problem with cooling systems for gas generators, a robust unit commitment problem with demand response and uncertain wind generation, and a power grid vulnerability analysis with transmission line switching. The latter two problems correspond to our theoretical contributions in two-stage robust optimization, i.e., how to efficiently solve a two-stage robust optimization, and how to deal with mixed-integer recourse in robust optimization. Due to copyright issue, this dissertation does not include any methodology papers written by the author during …


Measuring Technical Efficiency Of The Japanese Professional Football (Soccer) League (J1 And J2), Dan Zhao Jan 2013

Measuring Technical Efficiency Of The Japanese Professional Football (Soccer) League (J1 And J2), Dan Zhao

USF Tampa Graduate Theses and Dissertations

This is the first paper to measure the efficiency of the Japan Professional Football League clubs both the first and the second divisions. In Chapter 1, a non-parametric method Data Envelopment Development (DEA) is used and the data covers six seasons from 2005 to 2010. The input variables are payroll, cost besides payroll, and total assets. The output variables are attendance, revenue, and points awarded. I use different output combinations in order to check the sensitivity of the efficiency of the clubs after the original composition. This is also the first research to include more than one division of the …


Topological Degree And Variational Inequality Theories For Pseudomonotone Perturbations Of Maximal Monotone Operators, Teffera Mekonnen Asfaw Jan 2013

Topological Degree And Variational Inequality Theories For Pseudomonotone Perturbations Of Maximal Monotone Operators, Teffera Mekonnen Asfaw

USF Tampa Graduate Theses and Dissertations

Let X be a real reflexive locally uniformly convex

Banach space with locally uniformly convex dual space X*

. Let G be a

bounded open subset of X. Let T:X⊃ D(T)⇒ 2X*

be maximal

monotone and S: X ⇒ 2X*

be bounded

pseudomonotone and such that 0 notin cl((T+S)(D(T)∩partG)). Chapter 1 gives general introduction and mathematical prerequisites. In

Chapter 2 we develop a homotopy invariance and uniqueness results for the degree theory constructed by Zhang and Chen for multivalued (S+) perturbations of

maximal monotone operators. Chapter 3 is devoted to the construction of a new …


Magnetism In Complex Oxides Probed By Magnetocaloric Effect And Transverse Susceptibility, Nicholas Steven Bingham Jan 2013

Magnetism In Complex Oxides Probed By Magnetocaloric Effect And Transverse Susceptibility, Nicholas Steven Bingham

USF Tampa Graduate Theses and Dissertations

Magnetic oxides exhibit rich complexity in their fundamental physical properties determined by the intricate interplay between structural, electronic and magnetic degrees of freedom. The common themes that are often present in these systems are the phase coexistence, strong magnetostructural coupling, and possible spin frustration induced by lattice geometry. While a complete understanding of the ground state magnetic properties and cooperative phenomena in this class of compounds is key to manipulating their functionality for applications, it remains among the most challenging problems facing condensed-matter physics today. To address these outstanding issues, it is essential to employ experimental methods that allow for …


Development Of Novel Nano-Composite Membranes As Introduction Systems For Mass Spectrometers: Contrasting Nano-Composite Membranes And Conventional Inlet Systems, Luis Miranda Jan 2013

Development Of Novel Nano-Composite Membranes As Introduction Systems For Mass Spectrometers: Contrasting Nano-Composite Membranes And Conventional Inlet Systems, Luis Miranda

USF Tampa Graduate Theses and Dissertations

This dissertation presents the development of novel nano-composite membranes as introduction systems for mass spectrometers. These nano-composite membranes incorporate anodic aluminum oxide (AAO) membranes as templates that can be used by themselves or modified by a variety of chemical deposition processes. Two types of nano-composite membranes are presented. The first nano-composite membrane has carbon deposited within the pores of an AAO membrane. The second nano-composite membrane is made by coating an AAO membrane with a thin polymer film. The following chapters describe the transmission properties these nano-composite membranes and compare them to conventional mass spectrometry introduction systems. The nano- composite …


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 …


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 …


Accelerated Fuzzy Clustering, Jonathon Karl Parker Jan 2013

Accelerated Fuzzy Clustering, Jonathon Karl Parker

USF Tampa Graduate Theses and Dissertations

Clustering algorithms are a primary tool in data analysis, facilitating the discovery of groups and structure in unlabeled data. They are used in a wide variety of industries and applications. Despite their ubiquity, clustering algorithms have a flaw: they take an unacceptable amount of time to run as the number of data objects increases. The need to compensate for this flaw has led to the development of a large number of techniques intended to accelerate their performance. This need grows greater every day, as collections of unlabeled data grow larger and larger. How does one increase the speed of a …


Towards Interference-Immune And Channel-Aware Multicarrier Schemes: Filters, Lattices, And Interference Issues, Alphan Sahin Jan 2013

Towards Interference-Immune And Channel-Aware Multicarrier Schemes: Filters, Lattices, And Interference Issues, Alphan Sahin

USF Tampa Graduate Theses and Dissertations

In this dissertation, multicarrier schemes are reviewed within the framework of Gabor Systems. Their fundamental elements; what to transmit, i.e., symbols, how to transmit, i.e., filters or pulse shape, and where/when to transmit, i.e., lattices are investigated extensively. The relations between different types of multicarrier schemes are discussed.

Within the framework of Gabor systems, a new windowing approach, edge windowing, is developed to address the out-of-band (OOB) radiation problem of orthogonal frequency division multiplexing (OFDM) based multicarrier schemes. To the best of our knowledge, for the first time, the diversity on the range of the users is exploited to suppress …


Prevention And Detection Of Intrusions In Wireless Sensor Networks, Ismail Butun Jan 2013

Prevention And Detection Of Intrusions In Wireless Sensor Networks, Ismail Butun

USF Tampa Graduate Theses and Dissertations

Wireless Sensor Networks (WSNs) continue to grow as one of the most exciting and challenging research areas of engineering. They are characterized by severely constrained computational and energy

resources and also restricted by the ad-hoc network operational

environment. They pose unique challenges, due to limited power

supplies, low transmission bandwidth, small memory sizes and limited energy. Therefore, security techniques used in traditional networks cannot be directly adopted. So, new ideas and approaches are needed, in order to increase the overall security of the network. Security applications in such resource constrained WSNs with minimum overhead provides significant challenges, and is the …


Refinement, Application, And Evaluation Of Cognitive And Affective Chemistry Measures For College Students, Keily Heredia Jan 2013

Refinement, Application, And Evaluation Of Cognitive And Affective Chemistry Measures For College Students, Keily Heredia

USF Tampa Graduate Theses and Dissertations

This work describes three case studies conducted to address two major problems in the area of chemistry education research, the lack of reported psychometrics regarding instrument scores, and the need for well-characterized assessments to evaluate college chemistry curricula.

The first case study describes a psychometric evaluation of the Colorado Learning Attitudes about Science Survey (CLASS), an instrument designed to assess student beliefs about the learning of chemistry. Results from this work suggest that the CLASS instrument provides fertile ground for short instruments with reasonable psychometric properties. Responses to a single scale instrument, created from CLASS, showed that students in an …


A Study On The Optimization Of Dye-Sensitized Solar Cells, Md Imran Khan Jan 2013

A Study On The Optimization Of Dye-Sensitized Solar Cells, Md Imran Khan

USF Tampa Graduate Theses and Dissertations

Considering biocompatibility, the Dye Sensitized Solar Cell (DSC) based on titanium dioxide should play a major role in the future of solar energy. In this ongoing study, different components and ambient process conditions for the fabrication of were investigated. Titanium dioxide substrate thickness and morphology was found to have a direct impact on the cell efficiency. Scanning Electron Microscopy (SEM) was used to investigate the TiO2 nanostructure. Different chemical treatments and electrolytes were also explored towards optimizing the cell performance. A group of porphyrin based organic dyes were synthesized and evaluated. Standard solar cell characterization techniques such as current-voltage and …


Effect Of Solids Retention Time On The Denitrification Potential Of Anaerobically Digested Swine Waste, Maureen Njoki Kinyua Jan 2013

Effect Of Solids Retention Time On The Denitrification Potential Of Anaerobically Digested Swine Waste, Maureen Njoki Kinyua

USF Tampa Graduate Theses and Dissertations

Three continuously stirred tank reactors (CSTR) were operated in semi continuous mode treating swine waste using anaerobic digestion. The reactors were used to test the effect of solid retention time (SRT) on CH4 yield, total ammonia nitrogen (TAN) concentrations, % volatile solids (VS), chemical oxygen demand (COD) and volatile fatty acids (VFA) removal, readily biodegradable COD concentration and the denitrification potential for the effluent in a biological nutrient removal (BNR) system. During Phase I of the study, the three reactors were operated at the same 28 day SRT for 16 weeks. SRTs were then changed during the 12 week Phase …


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 …


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 …


Packet Coalescing And Server Substitution For Energy-Proportional Operation Of Network Links And Data Servers, Mehrgan Mostowfi Jan 2013

Packet Coalescing And Server Substitution For Energy-Proportional Operation Of Network Links And Data Servers, Mehrgan Mostowfi

USF Tampa Graduate Theses and Dissertations

Electricity generation for Information and Communications Technology (ICT) contributes over 2% of the human-generated CO2 to the atmosphere. Energy costs are rapidly becoming the major operational expense for ICT and may soon dwarf capital expenses as software and hardware continue to drop in price. In this dissertation, three new approaches to achieving energy-proportional operation of network links and data servers are explored.

Ethernet is the dominant wireline communications technology for Internet connectivity. IEEE 802.3az Energy Efficient Ethernet (EEE) describes a Low Power Idle (LPI) mechanism for allowing Ethernet links to sleep. A method of coalescing packets to consolidate link idle …