Digital Commons Network^™

Analysis Of Water Seepage Through Earthen Structures Using The Particulate Approach, Kalyani Jeyisanker

USF Tampa Graduate Theses and Dissertations

A particulate model is developed to analyze the effects of steady state and transient seepage of water through a randomly-packed coarse-grained soil as an improvement to conventional seepage analysis based on continuum models. In the new model the soil skeleton and pore water are volumetrically coupled. In the first phase of the study, the concept of relative density has been used to define different compaction levels of the soil layers of a completely saturated pavement filter system and observe the seepage response to compaction. First, Monte-Carlo simulation is used to randomly pack discrete spherical particles from a specified Particle Size …

Chemical Mechanical Planarization: Study Of Conditioner Abrasives And Synthesis Of Nano-Zirconia For Potential Slurry Applications, Chhavi Manocha

USF Tampa Graduate Theses and Dissertations

Chemical Mechanical Planarization (CMP) has emerged as the central technology for polishing wafers in the semiconductor manufacturing industry to make integrated multi-level devices. As the name suggests, both chemical and mechanical processes work simultaneously to achieve local and global planarization. In spite of extensive work done to understand the various components and parameters affecting the performance of this process, many aspects of CMP remain poorly understood. Among these aspects of CMP is the role of abrasives in the processes of conditioning and polishing. These abrasives are present in the chemical slurry between the wafer and the pad for polishing and …

Developments Toward A Micro Bistable Aerial Platform: Analysis Of The Quadrantal Bistable Mechanism, Aaron A. Muñoz

USF Tampa Graduate Theses and Dissertations

The Bistable Aerial Platform (BAP) has been developed in order to further enlarge the repertoire of devices available at the microscale. This novel device functions as a switch in that its platform can lock in two positions, up or down. Herein, it will be examined and explained, but a true understanding of its workings requires a better understanding of its compliant constituent parts. The Helico-Kinematic Platform (HKP), which serves as an actuator for the BAP, is currently under investigation by another researcher and will be merely touched upon here. The focus, therefore, will rest on the analysis of the Quadrantal …

Sequential Quantum-Dot Cellular Automata Design And Analysis Using Dynamic Bayesian Networks, Praveen Venkataramani

USF Tampa Graduate Theses and Dissertations

The increasing need for low power and stunningly fast devices in Complementary Metal Oxide Semiconductor Very large Scale Integration (CMOS VLSI) circuits, directs the stream towards scaling of the same. However scaling at sub-micro level and nano level pose quantum mechanical effects and thereby limits further scaling of CMOS circuits. Researchers look into new aspects in nano regime that could effectively resolve this quandary. One such technology that looks promising at nano-level is the quantum dot cellular automata (QCA). The basic operation of QCA is based on transfer of charge rather than the electrons itself. The wave nature of these …

Resting Oxygen Consumption Rates In Divers Using Diver Propulsion Devices, Adam J. Smith

USF Tampa Graduate Theses and Dissertations

The Marine Corps Systems Command documented mission requirements that cannot be met by current rebreathers. They need to extend dive times without compromising the stealth and compact design of existing devices. This can be accomplished by reducing the fresh gas flow rate. The current flow rate is adequate to support a diver in heavy work. However, the diver will be utilizing a Diver Propulsion Device (DPD) during a large portion of the mission in question. The assumption, then, is that this portion of the mission will not require "hard work". Thus, a new fresh gas flow rate can be established …

Theoretical Modeling Of Cortisol Sensor, Milorad Gordic

USF Tampa Graduate Theses and Dissertations

This thesis describes the theoretical modeling of a response of an electrochemical BioMEMS sensor for detecting small amounts of cortisol hormone. The electrochemical sensor utilizes a catalyst enzyme (3a-HSD) to convert cortisone to cortisol and the Square Wave Voltammetry (SWV) as a preferred method to measure the forward and reverse current of the system. The parameters and equations necessary to estimate the Square Wave Voltammetry (SWV) theoretical response are determined and outlined. The response is modeled and the results are compared to the experimental data. Further, the design of the sensor is analyzed and suggestions are made on how to …

Seepage Rates In Closed Basins, Volha Martysevich

USF Tampa Graduate Theses and Dissertations

Seepage is an important component of the water budget in closed basins that do not have surface water drainage features. In the shallow water table environment of Florida, internal drainage of soil controls flooding. With the recent rapid population growth and urban development in the state, a simple, field-based method is needed to estimate seepage rates. In this study five locations in Hillsborough County, Florida, were instrumented with wells with pressure transducers measuring water level fluctuations at 1 minute resolution. For closed basins with lakes, evaporation (E) rates were determined using data from a weather station and Penman-Monteith FAO56 method, …

The Robustness Of Rasch True Score Preequating To Violations Of Model Assumptions Under Equivalent And Nonequivalent Populations, Garron Gianopulos

USF Tampa Graduate Theses and Dissertations

This study examined the feasibility of using Rasch true score preequating under violated model assumptions and nonequivalent populations. Dichotomous item responses were simulated using a compensatory two dimensional (2D) three parameter logistic (3PL) Item Response Theory (IRT) model. The Rasch model was used to calibrate difficulty parameters using two methods: Fixed Parameter Calibration (FPC) and separate calibration with the Stocking and Lord linking (SCSL) method. A criterion equating function was defined by equating true scores calculated with the generated 2D 3PL IRT item and ability parameters, using random groups equipercentile equating. True score preequating to FPC and SCSL calibrated item …

Developing A School Social Work Model For Predicting Academic Risk: School Factors And Academic Achievement, Robert Lucio

USF Tampa Graduate Theses and Dissertations

The impact of school factors on academic achievement has become an important focus for school social work and revealed the need for a comprehensive school social work model that allows for the identification of critical areas to apply social work services. This study was designed to develop and test a more comprehensive school social work model. Specifically, the relationship between cumulative grade point average (GPA) and the cumulative risk index (CRI) and an additive risk index (ARI) were tested and a comparison of the two models was presented. Over 20,000 abstracts were reviewed in order to create a list of …

Formal Reasoning And Spatial Ability: A Step Towards "Science For All", Bo Jiang

USF Tampa Graduate Theses and Dissertations

This work conducts an evaluation of a non-majors science curriculum named Molecules of Life (MOL) that aims to provide effective science education to undergraduate students who are not majoring in scientific disciplines.

As part of the process of developing an assessment plan for MOL, three related studies were undertaken in order to help us choose assessment instruments for MOL. The first study examined the validity of student evaluations of teaching. The second study investigated the Test of Logical Thinking (TOLT) and Group Assessment of Logical Thinking (GALT), two widely-used instruments for measuring formal reasoning ability. GALT is very similar to …

Genetic Algorithm Based Design And Optimization Of Vlsi Asics And Reconfigurable Hardware, Pradeep Ruben Fernando

USF Tampa Graduate Theses and Dissertations

Rapid advances in integration technology have tremendously increased the design complexity of very large scale integrated (VLSI) circuits, necessitating robust optimization techniques in many stages of VLSI design. A genetic algorithm (GA) is a stochastic optimization technique that uses principles derived from the evolutionary process in nature. In this work, genetic algorithms are used to alleviate the hardware design process of VLSI application specific integrated circuits (ASICs) and reconfigurable hardware.

VLSI ASIC design suffers from high design complexity and a large number of optimization objectives requiring hierarchical design approaches and multi-objective optimization techniques. The floorplanning stage of the design cycle …

Kernel Density Estimation Of Reliability With Applications To Extreme Value Distribution, Branko Miladinovic

USF Tampa Graduate Theses and Dissertations

In the present study, we investigate kernel density estimation (KDE) and its application to the Gumbel probability distribution. We introduce the basic concepts of reliability analysis and estimation in ordinary and Bayesian settings. The robustness of top three kernels used in KDE with respect to three different optimal bandwidths is presented. The parametric, Bayesian, and empirical Bayes estimates of the reliability, failure rate, and cumulative failure rate functions under the Gumbel failure model are derived and compared with the kernel density estimates. We also introduce the concept of target time subject to obtaining a specified reliability. A comparison of the …

Correlates Of Mathematics Achievement In Developed And Developing Countries: An Hlm Analysis Of Timss 2003 Eighth-Grade Mathematics Scores, Ha T. Phan

USF Tampa Graduate Theses and Dissertations

Using eighth-grade mathematics scores from TIMSS 2003, a large-scale international achievement assessment database, this study investigated correlates of math achievement in two developed countries, Canada and the United States and two developing countries, Egypt and South Africa. Variation in math achievement within and between schools for individual countries was accounted for by a series of two-level HLM models. Specifically, there were five sets of HLM models representing student background, home resources, instructional practices, teacher background, and school background related factors. In addition, a final model was built by including all the statistically significant predictors in earlier models to predict math …

Three-Dimensional Microscopy By Laser Scanning And Multi-Wavelength Digital Holography, Alexander Khmaladze

USF Tampa Graduate Theses and Dissertations

This dissertation presents techniques of three-dimensional microscopy. First, an economical method of microscopic image formation that employs a raster-scanning laser beam focused on a sample, while non-imaging detector receives the scattered light is presented. The images produced by this method are analogous to the scanning electron microscopy with visible effects of shadowing and reflection. Compared to a conventional wide-field imaging system, the system allows for a greater flexibility, as the variety of optical detectors, such as PMT and position-sensitive quadrant photodiode can be used to acquire images. The system demonstrates a simple, low-cost method of achieving the resolution on the …

Dynamic Assessment: Towards A Model Of Dialogic Engagement, Robert Summers

USF Tampa Graduate Theses and Dissertations

This study investigated the effects of Dynamic Assessment (DA) training on the mediational strategies of experienced teachers of French as a foreign language. Moreover the strategies that mediators used for students at different levels of language experience were investigated. Last the ways in which mediators manifested mediational sensitivity, reciprocity and management was examined.

Four mediators underwent DA training that exposed them to the theoretical underpinnings of DA as well as sound DA procedures. To determine the effect of this training, the way in which the mediators conducted their mediation was compared from pre-DA training to post-DA training. Three of these …

Spray Deposition Of Biomolecular Thin Films, Mihir K. Rayan

USF Tampa Graduate Theses and Dissertations

In this paper, a parametric study of the airbrush deposition technique was investigated for the deposition biomolecular thin films. The airbrush parameters under investigation were intake valve opening, carrier gas pressure, distance between the airbrush and substrate, concentration of solution, vapor pressure of solvent, and hydrophobic/hydrophilic substrate surface. This study was assessed through the characterization of dried droplet residues of Bovine Serum Albumin (BSA) and of complete films of BSA by means of scanning electron microscopy (SEM) and atomic force microscopy (AFM). It was determined that droplet size was mainly affected by carrier gas pressure and vapor pressure. The parameters …

Control Of Autonomous Robot Teams In Industrial Applications, Athanasios Tsalatsanis

USF Tampa Graduate Theses and Dissertations

The use of teams of coordinated mobile robots in industrial settings such as underground mining, toxic waste cleanup and material storage and handling, is a viable and reliable approach to solving such problems that require or involve automation. In this thesis, abilities a team of mobile robots should demonstrate in order to successfully perform a mission in industrial settings are identified as a set of functional components. These components are related to navigation and obstacle avoidance, localization, task achieving behaviors and mission planning. The thesis focuses on designing and developing functional components applicable to diverse missions involving teams of mobile …

Quantitative Phase Imaging Microscopy With Multi-Wavelength Optical Phase Unwrapping, Nilanthi Warnasooriya

USF Tampa Graduate Theses and Dissertations

This dissertation presents a quantitative phase imaging microscopy technique that combines phase-shifting interferometry with multi-wavelength optical phase unwrapping. The technique consists of a Michelson-type interferometer illuminated with any of three types of light sources; light emitting diodes, laser diodes and a ring dye laser. Interference images are obtained by using a 4-frame phase shifting method, and are combined to calculate the phase of the object surface. The 2π ambiguities are removed by repeating the experiment combining two and three different wavelengths, which yields phase images of effective wavelength much longer than the original. The resulting image is a profile of …

Evaluating The Efficacy Of The Developing Algebraic Literacy Model: Preparing Special Educators To Implement Effective Mathematics Practices, Sharon N. E. Ray

USF Tampa Graduate Theses and Dissertations

For students with learning disabilities, positive academic achievement outcomes are a chief area of concern for educators across the country. This achievement emphasis has become particularly important over the last several years because of the No Child Left Behind legislation. The content area of mathematics, especially in the higher order thinking arena of algebra, has been of particular concern for student progress. While most educational research in algebra has been targeted towards remedial efforts at the high school level, early intervention in the foundational skills of algebraic thinking at the elementary level needs consideration for students who would benefit from …

Three Wittgensteins: Interpreting The Tractatus Logico-Philosophicus, Thomas J. Brommage Jr.

USF Tampa Graduate Theses and Dissertations

There are historically three main trends in understanding Wittgenstein's Tractatus. The first is the interpretation offered by the Vienna Circle. They read Wittgenstein as arguing that neither metaphysical nor normative propositions have any cognitive meaning, and thus are to be considered nonsense. This interpretation understands Wittgenstein as setting the limits of sense, and prescribing that nothing of substantive philosophical importance lies beyond that line. The second way of reading the Tractatus, which has became popular since the 1950s, is the interpretation which most currently accept as the early Wittgenstein's view; for this reason I refer to it …

Benzene Related Hematological Disorders: Evidence For A Threshold In Animals And Humans, James Mccluskey

USF Tampa Graduate Theses and Dissertations

Significant benzene exposure has historically been associated with the development of a host of hematological disorders in humans and animals. In particular, benzene is known to cause disturbances of the peripheral blood, aplastic anemia and cancer of the lymphohematopoietic system. In 1928, the first modern report of an association between cancer and benzene exposure was published. This case report was followed by additional reports from around the world. In most instances, ailments resulted from long term, high level exposure to benzene found in glues, and through accidental industrial spills. Throughout the 1960's and 1970's, case reports accumulated linking benzene exposure …

A Cross-Cultural Transformation That Drew Boundaries: Matteo Ricci And His Mapmaking In Ming China, Suet Yee Shery Chanis

USF Tampa Graduate Theses and Dissertations

This thesis examines the cartographic works of Italian Jesuit Matteo Ricci (1552-1610), who spent his last twenty-seven years in Ming China. In particular, by focusing on Ricci's 1602 map, I examine the broader significance of Ricci's cartographic production to understand how it reflected early modern Chinese-European exchanges. In addition to the 1602 map, I use Ricci's letters to construct a framework for his cartographic involvement. In his writings, Ricci revealed his rationale for mapmaking and explained his collection of information. Only one year after his entry into China, in 1584, Ricci compiled a world map in the Chinese language and …

Kandinsky’S Dissonance And A Schoenbergian View Of Composition Vi, Shannon M. Annis

USF Tampa Graduate Theses and Dissertations

In this study, I clarify the relationship between Wassily Kandinsky's move towards abstraction in painting and his encounters with the music and theory of Arnold Schoenberg. Prior studies have concentrated on the similarities in their theories, but I examine Kandinsky [sic] idiosyncratic understanding of Schoenbergian concepts and the evolution of his engagement with music theory over the period of 1909 to 1914. I identify dissonance as the aspect of Schoenberg's music and theory that Kandinsky found most relevant to his own developing compositional theory for abstract painting. In music, dissonance is commonly considered to be combinations of tones that sound …

Health Decision Behaviors: Appropriateness Of Dietary Choice, Daryle Hermelin Wane

USF Tampa Graduate Theses and Dissertations

Dietary choice is a complex mechanism that is influenced by multiple internal and external factors that impact individuals across the life span. The study was designed to examine how individuals make snack food choices based on integration of food motives (cues), appropriateness (nutritional index) as functions of nutritional knowledge, food-related motives, and information processing styles. Community college students participated in a multi part on line survey that ascertained food motives (FCQ), nutrition knowledge (FNQ), information processing (NFC), food pairing task and demographic background data. The single sided Lens model was used to determine the regression weights of the nine food …

Low Temperature Polymer Electrolyte Fuel Cell Performance Degradation, John Andrew Fedock

USF Tampa Graduate Theses and Dissertations

The goal of this research was to quantify the degradation experienced by a polymer electrolyte fuel cell after storage at subzero temperatures ranging from 0 to -40°C. The performance loss was determined by comparing the polarization and other applicable power curves before and after the subzero storage cycle. The causes of this performance degradation were investigated by the use of Scanning Electron Microscope, Energy Dispersive x-ray Spectroscopy, and porosity scanning technologies. It was found that there are two distinct types of degradation experienced by the membrane. The first type was identified as a variance of the actual voltage - current …

The Efficacy Of Florida’S Approach To In-Service English Speakers Of Other Languages Teacher Training Programs, Ronald D. Simmons Jr.

USF Tampa Graduate Theses and Dissertations

Much of how Florida and other states across the country justify the practice of mainstreaming English language learners into regular content classrooms rests on the premise that with the guidance of state officials, local school districts adequately train content teachers to work with English language learners. Yet little to no research exists that can help identify and analyze the overall efficacy of these programs. Consequently, this study has attempted to determine whether district training sessions in Florida are sufficiently covering the state-mandated content areas that teachers are required to learn and to what extent in-service teachers agree or disagree that …

Morphodynamics Of Two Anthropogenically Altered Tidal Inlets: New Pass And Big Sarasota Pass, West-Central Florida, Tanya M. Beck

USF Tampa Graduate Theses and Dissertations

Time-series aerial photographs from 1943 to 2006, including three bathymetry surveys from 1888, 1953, and 2006, are analyzed and compared. The locations of three morphological features, including that of shoreline, offshore bars, and channel orientation, are delineated over the historical aerial photos in order to examine the morphodynamics of the system. Anthropogenic alteration of the New Pass and Big Sarasota Pass system is a crucial factor in controlling the morphodynamics.

Both New Pass and Big Sarasota Pass are mixed-energy tidal inlets with New Pass illustrating a straight morphology and Big Sarasota Pass a highly offset morphology. The sediment bypassing at …

Detection Of Marine Vehicles In Images And Video Of Open Sea, Sergiy Fefilatyev

USF Tampa Graduate Theses and Dissertations

This work presents a new technique for automatic detection of marine vehicles in images and video of open sea. Users of such system include border guards, military, port safety, flow management, and sanctuary protection personnel. The source of images and video is a digital camera or a camcorder which is placed on a buoy or stationary mounted in a harbor facility. The system is intended to work autonomously, taking images of the surrounding ocean surface and analyzing them for the presence of marine vehicles. The goal of the system is to detect an approximate window around the ship. The proposed …

Maxwell’S Problem On Point Charges In The Plane, Kenneth Killian

USF Tampa Graduate Theses and Dissertations

This paper deals with approximating an upper bound for the number of equilibrium points of a potential field produced by point charges in the plane. This is a simplified form of a problem posed by Maxwell [4], who considered spatial configurations of the point charges. Using algebraic techniques, we will give an upper bound for planar charges that is sharper than the bound given in [6] for most general configurations of charges. Then we will study an example of a configuration of charges that has exactly the number of equilibrium points that Maxwell's conjecture predicts, and we will look into …

Determining The Quality And Impact Of An E-Mentoring Model On At-Risk Youth, Diane W. Culpepper

USF Tampa Graduate Theses and Dissertations

The purpose of this research was twofold. Since e-mentoring is relatively new, there have been very few studies that have explored the impact of an e-mentoring program on both the academic and psychological outcomes of its participants. In addition, there is little research on the quality of implementing, or what we will call the working quality, of an e-mentoring model. This study addressed both.

First, the study examined whether or not e-mentoring had an academic and psychological impact on 32 high school students who were at-risk of dropping out of school. The students were enrolled in a GED Exit Option …