Digital Commons Network^™

A Dynamic Inventory/Maintenance Model, Jonathan J. Bates

USF Tampa Graduate Theses and Dissertations

A model is proposed to provide inventory and maintenance guidance for a system of operating parts. This model is capable of handling a system with multiple operating components, unknown part lifetime failure distribution, and separately maintained parts. In this model, part reliability characteristics are used along with system costs to predict the required stocking levels and part replacement times. Two maintenance strategies are presented that have the unique characteristic of allowing flexible scheduling of replacements. A case study is completed comparing developed stocking policies to an existing policy. An estimation selection method is introduced and fit into the model for …

Cooperative Localization In Wireless Networked Systems, Mauricio Castillo-Effen

USF Tampa Graduate Theses and Dissertations

A novel solution for the localization of wireless networked systems is presented. The solution is based on cooperative estimation, inter-node ranging and strap-down inertial navigation. This approach overrides limitations that are commonly found in currently available localization/positioning solutions. Some solutions, such as GPS, make use of previously deployed infrastructure. In other methods, computations are performed in a central fusion center. In the robotics field, current localization techniques rely on a simultaneous localization and mapping, (SLAM), process, which is slow and requires sensors such as laser range finders or cameras.

One of the main attributes of this research is the holistic …

Silicon Carbide Biocompatibility, Surface Control And Electronic Cellular Interaction For Biosensing Applications, Camilla Coletti

USF Tampa Graduate Theses and Dissertations

Cell-semiconductor hybrid systems are a potential centerpiece in the scenery of biotechnological applications. The selection and study of promising crystalline semiconductor materials for bio-sensing applications is at the basis of the development of such hybrid systems. In this work we introduce crystalline SiC as an extremely appealing material for bio-applications. For the first time we report biocompatibility studies of different SiC polytypes whose results document the biocompatibility of this material and its capability of directly interfacing cells without the need of surface functionalization. Since the successful implementation of biosensors requires a good understanding and versatile control of the semiconductor surface …

The Effects Of Mentoring On The Elementary Special Education Mentor, Maria Angeliadis

USF Tampa Graduate Theses and Dissertations

Increasingly, mentor programs are being developed in teacher education programs to assist novice teachers. The focus in most of the literature on mentoring is on the new teacher being mentored. While the mentor teacher appears to be the most crucial element in mentoring programs (Feinman-Nemser, 1992; Little, 1990; White, 1995), there is not much information about how a teacher experiences being a mentor or the perceived benefits to a mentor.

The purpose of this present study was to examine the effects of mentoring on mentors in order to: (a) address the gap in the literature by exploring the effects of …

Evaluation Of The Supply Chain Of Key Industrial Sectors And Its Impact On The Electricity Demand For A Regional Distribution Company, Thiago Arruda Mariotoni

USF Tampa Graduate Theses and Dissertations

Considering the international scenario, in a recent past, the electrical industry was based on the concepts of monopolistic concessions and vertical utilities structures. In Brazil, until recently, the electricity companies were all governmental properties that served restricted monopolized areas. In a similar manner, in the United States, monopolies for certain concession areas were assigned to vertically integrated electric utilities. This monopolistic portfolio brought to the industry, in a generic sense, a lack in the interface between companies and consumers. This fact established a low capacity of obtaining consumer's information and consequently, a low capacity of developing precise demand forecasts.

Lately, …

Cost/Effectiveness Analysis Of Obtaining Operational Estimates Of Reference Evapotranspiration, Peninsular Florida, Usa, Michael G. Kittridge

USF Tampa Graduate Theses and Dissertations

The objective of this study is to conduct a cost/effectiveness analysis of the computation of reference evapotranspiration (ETo) in the peninsular of Florida. A meteorological station on the Fort Meade Mine in Polk County, Florida was used to provide data for the calculation of ETo. Five ETo equations were tested to determine the accuracy and cost/effectiveness to the fully measured ASCE Penman-Monteith (Full ASCE-PM) equation on daily, monthly, and annually time steps. The ETo equations ranged in amounts of parameters from the Full ASCE-PM to the Hargreaves. The energy terms accounted for approximately 90% of the total ETo flux. Solar …

The Effects Of Decision-Making And Leadership Styles On Relationships And Perceived Effectiveness In The University Development Context, Rachael K. Van Loveren

USF Tampa Graduate Theses and Dissertations

This study examined how employees' perceptions of leadership, decision-making, and relationships are associated with their perception of a development operations' effectiveness. Deans, development officers, central development staff, and unit development staff at the University of South Florida were surveyed via email. The results indicated that employees' perceptions of leadership, decision-making, and relationships are strongly related to their perceived job satisfaction, trust, commitment, and control mutuality and consequently their perception of the development operation's effectiveness.

Improving Pediatric Cardiology Consultation Methods By Introducing Digital Interactive 3-D Heart Models: A Proof Of Concept Study, Adam Verigan

USF Tampa Graduate Theses and Dissertations

The purpose of a pediatric cardiology consultation is to inform, or educate, the patient and family of all aspects surrounding a certain congenital heart defect. Consultation education methods and materials may include verbal descriptions, two-dimensional (2-D) heart diagrams, and take-home pamphlets. Because the human heart is a complex three-dimensional (3-D) object, the problem lies within the clarity to which these methods are performed by the doctors and understood by the patients and families. Therefore, during a consultation the cardiologist must a) possess the ability to describe a defect visually as well as verbally and b) ensure that the patient and …

Operational And Safety Effects Of Signage And Lighting Configurations For Public Transit Buses In Florida, Stephanie Antoinette Bromfield

USF Tampa Graduate Theses and Dissertations

Although public transit bus accounts for only a small percentage of the mode share for transportation in Florida, the annual passenger miles were over 1 billion with over 200 million passenger trips in 2005. These numbers warrant close attention to be paid to the safety of public transit vehicles. Despite the relatively low occurrence of fatalities and bus crashes, each crash of a high occupancy vehicle such as a public transit bus could expose more people to injury than a private automobile crash. Bus crashes also have a significant impact on the automobiles that are involved. Since a high percentage …

Wheelchair Positioning And Pulmonary Function In Children With Cerebral Palsy, Lee Barks

USF Tampa Graduate Theses and Dissertations

Background: In children with cerebral palsy (CP), poor trunk control fosters spinal deformity, pulmonary compromise (Canet, et al., 1998), increased health risks, and costs of long-term care (Braddock, 2001). Evidence links posture and pulmonary function, but influence of wheelchair parameters on pulmonary mechanics is unknown.

Objectives: 1) Determine relative contribution of five wheelchair configuration parameters to improvement in pulmonary mechanics--total airway resistance (RAW), tidal volume, minute ventilation (MV), and deadspace to tidal volume ratio; 2) Describe recruitment and retention of school-aged children with CP; and 3) Discuss response of the participants to the protocol.

Method: This within-subjects, descriptive study employed …

Cellmap: An Automated Multielectrode Array Cell Culture Analysis System Based On Electrochemical Impedance Spectroscopy, Abdur Rub Abdur Rahman

USF Tampa Graduate Theses and Dissertations

The objective of this research is to develop fundamental understanding of cell-substrate (CS) and cell-cell (CC) interactions in the culture space for time evolving cell cultures. Space resolved CC and CS interactions are important indicators of cell-density distribution, localized cellular behavior, and multiple cell-layers which are differentiators of normal and abnormal cell behavior. In this research, CS and CC interactions and the variations therein due to a) Cell growth, 2) cell-drug interaction, and 3) effect of Cytotoxin were studied using multielectrode, multi-frequency Electrochemical Impedance Spectroscopy (EIS). Contemporary impedance based methods sense either CC or CS interaction as a space averaged …

Electrochemical Behavior Of Aluminized Steel Type 2 In Scale-Forming Waters, Leonardo Caseres

USF Tampa Graduate Theses and Dissertations

Aluminized steel Type 2 (AST2), often used for culvert pipes, is subject to corrosion which is the most important durability limitation factor. It was desired to determine if the outer aluminized layer will retain passivity and if protective galvanic action will develop. Thus, corrosion of unblemished and blemished AST2 surfaces was investigated in simulated natural waters.

Experiments with unblemished specimens showed passive corrosion rates (~0.06 µm/yr) in scale-forming, 0.01 M Cl- solutions but sustained corrosion in other less protective media (with rates 3~10 µm/yr). Corrosion was manifested macroscopically by discoloration and few macro pits, but it likely proceeded also microscopically …

The Tip Of The Blade: Self-Injury Among Early Adolescents, Moya L. Alfonso

USF Tampa Graduate Theses and Dissertations

This study described self-injury within a general adolescent population. This study involved secondary analysis of data gathered using the middle school Youth Risk Behavior Survey (YRBS) from 1,748 sixth- and eighth-grade students in eight middle schools in a large, southeastern county in Florida. A substantial percentage of students surveyed (28.4%) had tried self-injury. The prevalence of having ever tried self-injury did not vary by race or ethnicity, grade, school attended, or age but did differ by gender. When controlling for all other variables in the multivariate model including suicide, having ever tried self-injury was associated with peer self-injury, inhalant use, …

Gate Level Dynamic Energy Estimation In Asynchronous Circuits Using Petri Nets, Ryan Mabry

USF Tampa Graduate Theses and Dissertations

This thesis introduces a new methodology for energy estimation in asynchronous circuits. Unlike existing probabilistic methods, this is the first simulative work for energy estimation in all types of asynchronous circuits.

The new simulative methodology is based on Petri net modeling. A real delay model is incorporated to capture both gate delays and interconnect delays. The switching activity at each gate is captured to measure the average dynamic energy consumed per request/acknowledge handshaking pair. The new type of Petri net is called Hierarchical Colored Asynchronous Hardware Petri net (HCAHPN). The HCAHPN is able to capture the temporal and spatial correlations …

“Girls Play With Dolls And Boys Play With Soldiers”: Examining Teachers And Parents' Gender Beliefs And The Gender Identity Of 8-10 Year Old Jamaican Boys, Christopher Carlyle Clarke

USF Tampa Graduate Theses and Dissertations

This multi-case ethnographic study examined the gender beliefs of two teachers and 12 parents and the gender identity of thirty 8-10 year old boys in two primary schools in Jamaica. The study was conducted against the background of gross underachievement among Jamaican boys and the research literature pointing to gender socialization as a factor in the declining results and interest in academic studies. Through 10 weeks of observations, interviews and focus group discussions answers were sought for the following questions:

1. What beliefs do teachers hold about gender?

2. What beliefs do parents hold about gender?

3. What are boys' …

Communication For Planetary Transformation And The Drag Of Public Conversations: The Case Of Landmark Education Corporation, Patrick Owen Cannon

USF Tampa Graduate Theses and Dissertations

This study employs qualitative methods to: (1) compare and contrast public conversations about a complex social phenomenon with my experience of that phenomenon, and (2) explore the nature of those public conversations and their impact on planetary transformation.

This study is divided into two parts.

Part One of this dissertation compares my personal experience with Landmark Education Corporation, a private personal development company, with how it is characterized in public conversations. The public conversations chosen for analysis include: (1) an episode of the television show, Law and Order: Criminal Intent (Balcer, et al., 2003), (2) a Time Magazine article about …

Development Of Research Platform For Unmanned Vehicle Controller Design, Evaluation, And Implementation System: From Matlab To Hardware Based Embedded System, Daniel Ernst

USF Tampa Graduate Theses and Dissertations

Unmanned aerial vehicles and unmanned ground vehicles, or UAVs and UGVs respectively, currently perform a large variety of missions usually centered around reconnaissance. Because the platforms may vary for a particular type of mission--everything from small unmanned airplanes and remote control vehicles to large vehicles such as the Yamaha R-MAX helicopter and Hummer--flight and navigation controllers must be changed to allow proper control of the selected platform. Currently, controllers are designed and tested in MATLAB/SIMULINK, but then rewritten in C or Assembly for a specific target platform. When designing controllers in a programming language, changes are often tedious, so …

The Validation Of A Methodology For Assessing The Impact Of Hybrid Simulation Training In The Minimization Of Adverse Outcomes In Surgery, Peter J. Fabri

USF Tampa Graduate Theses and Dissertations

The Institute of Medicine report "To Err is Human," released in late 1999, raised the issue of human error in medicine to a new level of attention. This study examines the frequency, severity, and type (FST) of errors associated with postoperative surgical complications at a tertiary care, university-based medical center, addressing the intersection of three domains: patient safety, graduate medical education, and simulation-based training. The study develops and validates a classification system for medical error that is specific to surgery, affirming reliability internally and externally. Baseline data on the FST of errors is collected over a 12-month period. A hybrid, …

Low Temperature Hermetically Sealed 3-D Mems Device For Wireless Optical Communication, Rahul Agarwal

USF Tampa Graduate Theses and Dissertations

Novel processes were developed that resulted in a self-packaged device during the system integration, along with a transparent lid for inspection or optical probing. A new process was developed for improving the verticality in Micro Electro Mechanical Systems (MEMS) structures using Deep Reactive Ion Etching (DRIE). A self-pattered, mask-less photolithography technique was developed to metallize these vertical structures while maintaining a transparent window, for packaging of various MEMS devices. The verticality and metallization coverage were evaluated by incorporating the MEMS structures into an optical Corner Cube Retroreflector (CCR). A low temperature, hermetic sealing technique was also developed using In-Au thermo-compression …

Florida's College Placement Test Reading Scores As An Essential Indicator For Successful Completion Of The Highest College Preparatory Course In Reading, Laura Dandar Smith

USF Tampa Graduate Theses and Dissertations

The purpose of this study was to examine the predictive validity of several variables to determine if the Florida Computerized Placement Test - Reading (CPT-R) score alone, or other variables, could determine whether or not a student would successfully pass the highest level college preparatory reading course. The study examined fall sessions 1997-2004 (n=276,079) reading scores for all forms of the CPT to determine at what standard deviation below the cutoff score of 83 a student could still successfully complete the highest level college preparatory reading course.

According to the College Board, the 83 scaled score, which exempts a student …

The Historical Production Of Elemental Phosphorus In Pinellas County, Florida: An Environmental Assessment, Stephen D. Robinson

USF Tampa Graduate Theses and Dissertations

This thesis was completed in order to assess and document the environmental effects that are the result of elemental phosphorus production in Pinellas County Florida. The study utilized a collection of information resources that included: personal interviews, technical references, historical documents, legal documents and field observations. By utilizing five different sources of information a broad understanding of the problem was developed.

Pinellas County and Tarpon Springs officials were interested in creating a more diversified economy in the years following World War-II. The Victor Chemical Works Company responded to the interest in economic diversity by proposing to build an elemental phosphorus …

Modeling Three-Dimensional Shape Of Sand Grains Using Discrete Element Method, Nivedita Das

USF Tampa Graduate Theses and Dissertations

The study of particle morphology plays an important role in understanding the micromechanical behavior of cohesionless soil. Shear strength and liquefaction characteristics of granular soil depend on various morphological characteristics of soil grains such as their particle size, shape and surface texture. Therefore, accurate characterization and quantification of particle shape is necessary to study the effect of grain shape on mechanical behavior of granular assembly. However, the theoretical and practical developments of quantification of particle morphology and its influence on the mechanical response of granular assemblies has been very limited due to the lack of quantitative information about particle geometries, …

Learning On Complex Simulations, Robert E. Banfield

USF Tampa Graduate Theses and Dissertations

This dissertation explores Machine Learning in the context of computationally intensive simulations. Complex simulations such as those performed at Sandia National Laboratories for the Advanced Strategic Computing program may contain multiple terabytes of data. The amount of data is so large that it is computationally infeasible to transfer between nodes on a supercomputer. In order to create the simulation, data is distributed spatially. For example, if this dissertation was to be broken apart spatially, the binding might be one partition, the first fifty pages another partition, the top three inches of every remaining page another partition, and the remainder confined …

Novel Polymer-Metal Nanocomposites For Applications In Detection And Sensing, Dayling L. Chaparro

USF Tampa Graduate Theses and Dissertations

Detection of trace elements such as organic contaminants, explosive residues, and metal ions is an intellectually challenging task in science and engineering. It is also a topic of increasing importance due to its impact on society and the environment. Designing molecularly imprinted materials is one of the most promising approaches to explore sensing and detection applications. “Stimuli-sensitive” polymer materials are ideal candidates for these imprinted sensors as they are able to respond to changes in their environment and can be tailored by cross-linking the polymer chains. The responses can be amplified and transduced into measurable signals due to macromolecular properties …

Growth Factor-Mediated Telomerase Activity In Ovarian Cancer Cells, Yira Bermudez

USF Tampa Graduate Theses and Dissertations

Ovarian cancer is the leading cause of gynecological cancer death in the United States. Even though no single genetic alteration can be attributed to all ovarian cancers, 90% of ovarian tumors express telomerase, a ribonucleoprotein that elongates telomeric (TTAGGG)n repeats de novo. In normal somatic cells, telomerase is absent. In cancer cells, the re-expression of telomerase allows senescence to be bypassed contributing to cellular immortalization, a key step for cellular transformation, making telomerase a potentially important target for therapeutic intervention.

Ovarian cancer cells secrete vascular endothelial growth factor (VEGF) and lysophosphatidic acid (LPA) that feedback through their receptors present …

Evanescent Field Absorption Sensing Using Sapphire Fibers, Michael Grossman

USF Tampa Graduate Theses and Dissertations

This thesis explores the application of coiled sapphire multimode optical fibers for evanescent wave chemical sensing in both the visible spectrum and the near infrared. As has been suggested in the literature pertaining to silica fibers, bending converts low-order modes to high order ones, which leads to more evanescent absorption and thus a more sensitive chemical detector. By coiling the fiber many times, it was expected that even greater sensitivity would be attained.

Experiments were performed to investigate the sensor response to different solutions and to characterize this response. In the first of three experiments, the large absorption peak of …

Influence Of Evapotranspiration On Patterns Of Ground-Water Conductivity In Small Basins, Ana Jiménez

USF Tampa Graduate Theses and Dissertations

Ground-water conductivity data were obtained from shallow wells in a 12 km2 stream-basin along a 400 m transect, extending from the divide to the stream. The stream, Pringle Branch, is a second-order perennial stream in Hillsborough County, Florida. The shallow stratigraphy consists of 2-3 m of fine sand over a layer of clayey silt and silty clay. Vegetation cover includes grasses on the upper and middle slope, and riparian woodlands on the foot slope and floodplain. Precipitation is about 1.3 m per year. Shallow ground-water conductivity is about 50 uS/cm at the divide. It increases moderately along the mid slope, …

Glyconanobiotics: Novel Carbohydrated Nanoparticle Polymers, Thotaha Wijayahewage Sampath Chrysantha Abeylath

USF Tampa Graduate Theses and Dissertations

Carbohydrates on the cell surface conjugates to proteins and lipids and participates in biological processes as glycoconjugates. Carbohydrate functionalized nanoparticles (glyconanoparticles) constitute a good bio-mimetic model of carbohydrate presentation at the cell surface and are currently centered on many glycobiological and biomedical applications. The most of the applications have been reported using gold glyconanoparticles. A brief review of gold glyconanoparticles and some of their applications will be discussed in Chapter I. Although metallic, semiconductor and magnetic glyconanoparticles have been reported, no polyacrylate glyconanoparticles have yet to be described.

Chapter II describes the first preparation of carbohydrate functionalized polymer nanoparticles by …

Fabrication And Analysis Of Poly(3-Hexylthiophene) Interfaces Using Electrospray Deposition And Photoemission Spectroscopy, John Lyon

USF Tampa Graduate Theses and Dissertations

P3HT (Poly(3-hexylthiophene)) is an organic polymer that shows promise as an active material in semiconducting electronics. It is important to study the electronic properties of this material in order to determine its efficacy in such devices. However, many current studies of thiophene only examine the oligomer, since it is a simpler material to investigate.

In this study, several P3HT interfaces were analyzed to determine their electronic properties. The P3HT was deposited on Au, highly-ordered pyrolitic graphite (HOPG), and indium tin oxide (ITO) substrates via electrospray deposition. The depositions were performed in several steps, with x-ray photoemission spectroscopy (XPS) and ultraviolet …

On Comparison Of Indentation Models, John Louis Daly Jr.

USF Tampa Graduate Theses and Dissertations

Thin films that are functionally gradient improve the mechanical properties

of film-substrate layered materials. Mechanical properties of such materials are

found by using indentation tests. In this study, finite element models are

developed to simulate the indentation test. The models are based on an

axisymmetric half space of a specimen subjected to spherical indentation. The

film layer through the thickness is modeled to have either homogeneous material

properties or nonhomogeneous material properties that vary linearly.

Maximum indenter displacement, and maximum normal and shear

stresses at the interface are compared between the homogeneous model and

the nonhomogeneous model for pragmatic contact …