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Multi-Time Scales Stochastic Dynamic Processes: Modeling, Methods, Algorithms, Analysis, And Applications, Jean-Claude Pedjeu

USF Tampa Graduate Theses and Dissertations

By introducing a concept of dynamic process operating under multi-time scales in sciences and engineering, a mathematical model is formulated and it leads to a system of multi-time scale stochastic differential equations. The classical Picard-Lindel\"{o}f successive approximations scheme is expended to the model validation problem, namely, existence and uniqueness of solution process. Naturally, this generates to a problem of finding closed form solutions of both linear and nonlinear multi-time scale stochastic differential equations. To illustrate the scope of ideas and presented results, multi-time scale stochastic models for ecological and epidemiological processes in population dynamic are exhibited. Without loss in generality, …

Graphene Casimir Interactions And Some Possible Applications, Anh Duc Phan

USF Tampa Graduate Theses and Dissertations

Scientific development requires profound understandings of micromechanical and nanomechanical systems (MEMS/NEMS) due to their applications not only in the technological world, but also for scientific understanding. At the micro- or nano-scale, when two objects are brought close together, the existence of stiction or adhesion is inevitable and plays an important role in the behavior operation of these systems. Such effects are due to surface dispersion forces, such as the van der Waals or Casimir interactions. The scientific understanding of these forces is particularly important for low-dimensional materials. In addition, the discovery of materials, such as graphitic systems has provided opportunities …

Socioscientific Issues: A Path Towards Advanced Scientificliteracy And Improved Conceptual Understanding Of Socially Controversial Scientific Theories, Dean William Pinzino

USF Tampa Graduate Theses and Dissertations

Abstract

This thesis investigates the use of socioscientific issues (SSI) in the high school science classroom as an introduction to argumentation and socioscientific reasoning, with the goal of improving students' scientific literacy (SL). Current research is reviewed that supports the likelihood of students developing a greater conceptual understanding of scientific theories as well as a deeper understanding of the nature of science (NOS), through participation in informal and formal forms of argumentation in the context of SSI. Significant gains in such understanding may improve a student's ability to recognize the rigor, legitimacy, and veracity of scientific claims and better discern …

Development Of Interatomic Potentials For Large Scale Molecular Dynamics Simulations Of Carbon Materials Under Extreme Conditions, Romain Perriot

USF Tampa Graduate Theses and Dissertations

The goal of this PhD research project is to devise a robust interatomic potential for large scale molecular dynamics simulations of carbon materials under extreme conditions. This screened-environment dependent reactive empirical bond order potential (SED-REBO) is specifically designed to describe carbon materials under extreme compressive or tensile stresses. Based on the original REBO potential by Brenner and co workers, SED-REBO includes reparametrized pairwise interaction terms and a new screening term, which serves the role of a variable cutoff. The SED-REBO potential overcomes the deficiencies found with the most commonly used interatomic potentials for carbon: the appearance of artificial forces due …

Academic Affairs Officers: An Application Of The American Association Of Community Colleges Competencies For Community College Leaders, Misty Renee Price

USF Tampa Graduate Theses and Dissertations

Over the last two decades, several studies have confirmed that there is a leadership crisis among the nation's community colleges. In response to this leadership crisis, the American Association of Community Colleges [AACC] commissioned the development of a leadership competency framework consisting of six leadership competency areas deemed "either `very' or `extremely' essential to the effective performance of community college leaders." Since the release of this framework, limited research has been conducted on the importance of and the preparation in the identified competencies. The majority of research that has been conducted has focused on the position of president, even though …

Sensitivity Of Value Added School Effect Estimates To Different Model Specifications And Outcome Measures, Bryce L. Pride

USF Tampa Graduate Theses and Dissertations

The Adequate Yearly Progress (AYP) Model has been used to make many high-stakes decisions concerning schools, though it does not provide a complete assessment of student academic achievement and school effectiveness. To provide a clearer perspective, many states have implemented various Growth and Value Added Models, in addition to AYP. The purpose of this study was to examine two Value Added Model specifications, the Gain Score Model and the Layered Effects Model, to understand similarities and differences in school effect results. Specifically, this study correlated value added school effect estimates, which were derived from two model specifications and two outcome …

Sustainable Livelihood Analysis Of An Irrigation Project In Ta Haen, Cambodia., Irene Rehberger Bescos

USF Tampa Graduate Theses and Dissertations

This study examines potential livelihood outcomes from a recently established irrigation project in Ta Haen, Cambodia, in a sustainable livelihoods framework. The aim of this SAUCE irrigation project is to provide water for drinking and irrigation purposes with the goal of enhancing food by producing an extra rice harvest, the staple, per year. Field research conducted in December 2011 provided qualitative data from questionnaires, key informant interviews, and participant and direct observation, in addition to quantitative data from water quality analysis focusing on arsenic (a potential risk), pH, EC and temperature. Most of the people in the village did not …

Responses To Chemical Exposure By Foraminifera: Distinguishing Dormancy From Mortality, Benjamin James Ross

USF Tampa Graduate Theses and Dissertations

The Deepwater Horizon blowout in 2010 released an estimated 4.9 million barrels of crude oil into the Gulf of Mexico in the 83 days between the initial explosion and the capping of the well. Response included extensive use of Corexit© oil dispersant. Although South Florida was spared exposure by currents, this event highlights the need for effective bioassay organisms for coral reefs. Amphistegina spp. are benthic foraminifers that host diatom symbionts in a relationship similar to that of coral and their zooxanthellae. Amphistegina spp. occur abundantly in reef communities nearly worldwide, are easily collected and maintained in culture, and are …

Stochastic Hybrid Dynamic Systems: Modeling, Estimation And Simulation, Daniel Siu

USF Tampa Graduate Theses and Dissertations

Stochastic hybrid dynamic systems that incorporate both continuous and discrete dynamics have been an area of great interest over the recent years. In view of applications, stochastic hybrid dynamic systems have been employed to diverse fields of studies, such as communication networks, air traffic management, and insurance risk models. The aim of the present study is to investigate properties of some classes of stochastic hybrid dynamic systems.

The class of stochastic hybrid dynamic systems investigated has random jumps driven by a non-homogeneous Poisson process and deterministic jumps triggered by hitting the boundary. Its real-valued continuous dynamic between jumps is described …

Use And Development Of Computational Tools In Drug Discovery: From Small Molecules To Cyclic Peptides, Daniel Navarrete Santiago

USF Tampa Graduate Theses and Dissertations

The scope of this work focuses on computationally modeling compounds with protein structures. While the impetus of drug discovery is the innovation of new therapeutic molecules, it also involves distinguishing molecules that would not be an effective drug. This can be achieved by inventing new tools or by refining old tools. Virtual screening (VS, also called docking), the computational modeling of a molecule in a receptor structure, is a staple in predicting a molecule's affinity for an intended target. In our Virtual Target Screening system (also called inverse-docking), VS is used to find high-affinity targets, which can potentially explain absorption, …

Properties Of Ferroelectric Perovskite Structures Under Non-Equilibrium Conditions, Qingteng Zhang

USF Tampa Graduate Theses and Dissertations

Ferroelectric materials have received lots of attention thanks to their intriguing properties such as the piezoelectric and pyroelectric effects, as well as the large dielectric constants and the spontaneous polarization which can potentially be used for information storage. In particular, perovskite crystal has a very simple unit cell structure yet a very rich phase transition diagram, which makes it one of the most intensively studied ferroelectric materials. In this dissertation, we use effective Hamiltonian, a first-principles-based computational technique to study the finite-temperature properties of ferroelectric perovskites. We studied temperature-graded

(BaxSr1-x )TiO3 (BST) bulk alloys as well as the dynamics of …

A Phenomenological Study Of Teaching Endangered Languages Online: Perspectives From Nahua And Mayan Educators., Dustin De Felice

USF Tampa Graduate Theses and Dissertations

Language and culture teaching has always been a complex and challenging task. For many educators, their teaching experiences are rooted in their earlier preparation, their classroom situations and their curriculum. In this study, indigenous educators recount their lived experiences with teaching their language and culture at a distance. These educators belong to either Nahua or Mayan speech communities where endangered languages are maintained. Using a transcendental phenomenological approach, my participants described and explained their perspectives and experiences with teaching, studying, and integrating technology. I focused the interviews, the reflective writing tasks and their artifact sharing on their experiences in an …

The Link Between Image Segmentation And Image Recognition, Karan Sharma

Dissertations and Theses

A long standing debate in computer vision community concerns the link between segmentation and recognition. The question I am trying to answer here is, Does image segmentation as a preprocessing step help image recognition? In spite of a plethora of the literature to the contrary, some authors have suggested that recognition driven by high quality segmentation is the most promising approach in image recognition because the recognition system will see only the relevant features on the object and not see redundant features outside the object (Malisiewicz and Efros 2007; Rabinovich, Vedaldi, and Belongie 2007). This thesis explores the following question: …

Understanding The Emission From Semiconductor Nanoparticles, Beth Ann Manhat

Dissertations and Theses

This dissertation describes the synthesis and characterization of fluorescent semiconductor nanoparticles (NPs) in order to optimize their biomedical utility for imaging and sensing applications. While both direct and indirect bandgap semiconductor NPs have been studied, control over their emission properties vary. Quantum confinement (QC), which primarily controls the emission wavelength of nanosized semiconductors, dictates that as the size of semiconductor NPs decrease, the magnitude of the bandgap increases, resulting in changes in the observed emission wavelength: smaller NPs have a larger bandgap, and thus a bluer emission. However, surface, interfacial, or shell defects can act as non-radiative or radiative recombination …

Development And Implementation Of Acoustic Feedback Control For Scanning Probe Microscopy, Rodolfo Fernandez Rodriguez

Dissertations and Theses

A remote-sensing acoustic method for implementing position control feedback in Scanning Probe Microscopy (SPM) is presented. The capabilities of this feedback control using the new Whispering Gallery Acoustic Sensing (WGAS) method is demonstrated in a Shear-force Scanning Probe Microscope that uses a sharp probe attached to a piezoelectric Quartz Tuning Fork (QTF) firmly mounted on the microscope's frame. As the QTF is electrically driven its mechanical response reaches the SPM frame which then acts as a resonant cavity producing acoustic modes measured with an acoustic sensor strategically placed on the SPM head. The novelty of the WGAS resides in using …

A Systems Approach To Ecological Economic Models Developed Progressively In Three Interwoven Articles, Takuro Uehara

Dissertations and Theses

My dissertation develops and analyzes ecological economic models to study the complex dynamics of an ecological economic system (EES) and investigate various conditions and measures which can sustain a developing economy over the long term in view of resilience and sustainability. Because of the intrinsic complexity of the system, I take a systems approach, using economics as the foundation for the basic structure of an ecological economic model, and system dynamics as the method to build and analyze such a complex ecological economic model. Throughout my dissertation, the model developed by Brander and Taylor (1998) is adopted as a baseline …

Climate Change Effects And Water Vulnerability In The Molalla Pudding River Basin, Oregon, Usa, Susan Amelia Wherry

Dissertations and Theses

Water management plans are typically developed using historical data records and historical return periods for extreme events, such as floods or droughts. Since these analyses of return periods typically assume a certain degree of stationarity (constant mean, standard deviation, distribution) in hydrologic variables, the potential future impacts of climate change are excluded. In developing water management plans, predicted changes to climate variables should be considered to evaluate the degree of non-stationarity that may exist in the future. In this way, regions most sensitive to climate change can be identified and managed appropriately. This study performed such a task by using …

Artificial Oyster Reefs In The Northern Gulf Of Mexico: Management, Material, And Faunal Effects, Jessica Nicole Furlong

LSU Master's Theses

Artificial oyster reefs seek to restore reef ecosystem services, such as water filtration, shoreline protection, and habitat for nekton. This study established three objectives to address the dispersed nature of artificial reef information in the Gulf of Mexico (GoM) and lack of post-construction monitoring assessments. First, to document the extent of activities in the GoM, we developed a database of all inshore artificial oyster reefs created for restoration purposes. Of the 422 reefs in the resultant database, a third or less provided records of entities involved (27%), restoration goals (24%), area (20%), monitoring efforts (15%), relief (9%), and costs (8%). …

Carl Schmitt's Radical Democracy: Schmitt, Hobbes And The Return To Political Identity, Ndifreke Ette

LSU Master's Theses

Scholarly treatments of the controversial German jurist Carl tend to be bipolar: His writings are either scrutinized for totalitarian leanings or his flirtations with Nazism excused as unfortunately opportunistic. One of the more fruitful points to begin an exploration of Schmitt’s thought is in his interpretation of Thomas Hobbes. Schmitt criticized Hobbes both for ignoring the historical backdrop to the Leviathan myth, and also for prefiguring liberalism with his distinction between conscience and obedience. In recruiting Hobbes, this paper suggests that though Schmitt’s concern about the technologization of politics through liberalism was paramount, it was in support of a radical …

Design And Analysis Of Cloaked Fluorophores For Rapid Detection And Visualization Of Cancer Cells Containing Nad(P)H:Quinone Oxidoreductase-1, William Silvers

LSU Doctoral Dissertations

The development of fluorogenic substrates for real-time tumor cell detection has led to a vastly expanding field for personal oncology. Fluorophores have been studied as appendages to larger scaffolds leading to accumulation of these dyes in tumor cells or their surrounding environment, taking advantage of tumor anatomy. A new class of fluorophores has been developed in which the dye is an active participant in the mechanism of cancer cell detection. These dyes have been conjugated such that their fluorescence has been eliminated or altered and will undergo a change to reveal their fluorescent signal upon activation by a mechanism that …

Development And Validation Of An Electron Monte Carlo Model For The Elekta Infinity Accelerator, Guy Merritt Harris

LSU Master's Theses

Purpose: The purpose of this work was to create a Monte Carlo BEAMnrc/EGSnrc model of the electron beam delivery system of an Elekta Infinity linear accelerator that could simulate electron percent depth doses and off-axis profiles to within a specified tolerance criteria, ±2% relative quantities (Dmax) or 1 mm distance to agreement (DTA), when compared to a subset of the measured commissioning data for the accelerator’s existing set of scattering foils and applicators. Methods: The model was constructed with the BEAMnrc user code from vendor provided schematics and correspondence with manufacturer engineers under a nondisclosure agreement. The spatial distribution of …

Object Protocols As A Tool For Debugging Method Call Sequencing Constraints, Ronald William Gilkey

LSU Master's Theses

Clearly conveying and enforcing the proper ordering of method calls on objects has become a common problem among developers and interface designers. Without the ability of the compilation environment to enforce these constraints, programmers must rely on clear documentation being provided and diligence in programming to ensure that a proper sequence of operations is performed. Commonly, though, type-checking becomes the only tool to help support the correctness of operation sequences as API documentation rarely describes inter-object communications. Thus, the likeliness of producing erroneous and buggy software increases. Object protocols provide a simple and straight-forward approach to solving this problem. They …

The Context Of Public Acceptance Of Hydraulic Fracturing: Is Louisiana Unique?, Crawford White

LSU Master's Theses

Hydraulic fracturing has received increased attention over the past decade. The rapid adoption of this technique coupled with accurate directional horizontal drilling has unlocked several US shale formations. Amid the possibility of 100% domestically sourced natural gas, public perception varies and opponents question the long-term risks and repercussions of the technique. This thesis will provide context to some of the variation seen in the public perception of hydraulic fracturing among three states: Louisiana, Pennsylvania, and Texas. Two surveys of Louisiana stakeholders were conducted in order to rank the state in terms of acceptance amongst previously conducted surveys of its two …

The Economic Feasibility Of Utilizing Energy Cane In The Cellulosic Production Of Ethanol, Kayla Lynn Brown

LSU Master's Theses

With an overall lack of economic information available on energy cane production, the aim of this research has been to provide some insight on the economic feasibility of producing energy cane in Louisiana as a feedstock for cellulosic ethanol production. When dealing with a non-traditional crop such as energy cane, increased uncertainty surrounding potential costs and returns can make the crop seem much less appealing to potential producers. As a high-fiber hybrid of traditionally produced sugarcane, energy cane production costs have been estimated using a standard enterprise budgeting approach developed for sugarcane, along with actual yield and fiber data from …

Evaluation Of A Proton Pencil Bean Algorithm For Dose Calculations In Heterogenous Media, Nels C. Knutson

LSU Master's Theses

Purpose: To develop an improved nuclear halo dose model of a pencil beam algorithm (PBA) for dose calculation of proton beams in heterogeneous media. Methods: The proton PBA consisted of a central axis term and an off axis term. The central axis term was determined from a central axis depth dose profile of a Monte Carlo simulated proton beam in water and was scaled by a mass stopping power ratio to account for other materials. The off axis term was determined from Fermi-Eyges scattering theory with material-dependent scattering powers to calculate the lateral spread of the proton beam in heterogeneous …

An Experimental And Theoretical Critique Of Flow Model Accuracy, Shannon Ray Chollett

LSU Master's Theses

In today’s exploration and production environment it is required that engineers must collect and use vast amounts of data for flow model construction and calibra- tion, as well as reservoir estimation and optimization. With modern technology, the data volume can be overwhelming. It is necessary that data monitoring and calibration are highly efficient. It is also essential that physical and mathematical models can be tested in repeatable, inexpensive experiments. The experiments described in this thesis will develop and perform verification of algorithms and can generate prior geomodels, collect and process seismic refraction data, collect and process production data, and calibrate …

Focus Question Effect On Dynamic Thinking In A Concept Map, Blake John Orgeron

LSU Master's Theses

A concept map is an educational tool designed to help identify, represent, and categorize relationships between different ideas relating to an overall concept. Relationships or transitions between the ideas are created by students and can either be static or dynamic. Static transitions help to describe, define, and organize knowledge for a given domain. Dynamic transitions show how a change in quantity, quality, or state in one concept causes change in quantity, quality, or state in the other concept. The focus question of the map directs student input of the concepts and ultimately determines what types of transitions are used. The …

Systematic Government Access To Private-Sector Data, Fred H. Cate, James X. Dempsey, Ira S. Rubenstein

Articles by Maurer Faculty

No abstract provided.

Programming And Healing Temperature Effects On The Efficiency Of Confined Self-Healing Polymers, Yves Quentin Yougoubare

LSU Master's Theses

Shape memory polymers are smart materials capable of fixing a temporary shape and returning to their initial shape in response to an external stimulus. Since the discovery and acknowledgment of their importance in 1960s, shape memory polymers have been the subject of tremendous and continuous attention. In a previous study conducted on a biomimetic shape memory polymer (SMP), the ability of a self-healing composite to heal, and to repair and restore structural-length scale damage using a close-then-heal (CTH) self-healing mechanism was examined and validated. The present study is purposed with investigation of the effects on healing efficiencies of the variation …

"Gift Of The Word" Exhibit Catalogue, Katherine Bass, Karena Bennett, Jeffrey Brown, Bronwyn Dorhofer, Normandie Holmes, Denise Loncar, Alexandra Park, Darcie Hart Riedner, Christy Valentine

Gift of the Word

This is the catalogue for the exhibit "Gift of the Word"