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Salinity- And Temperature-Dependent Groundwater Flow In The Floridan Aquifer System Of South Florida, Joseph D. Hughes

USF Tampa Graduate Theses and Dissertations

Density-dependent groundwater flow in the Floridan aquifer system (FAS) depends on chloride concentrations and fluid temperature. Previous studies addressing the role of chloride concentration and temperatures on groundwater flow in the FAS have relied on observation data or simplified two-dimensional numerical models. A three-dimensional hydrologic analysis of FAS in peninsular Florida was performed using a modified version of SUTRA (SUTRA-MS) capable of simulating multi-species solute and heat transport. SUTRA-MS was developed during this investigation and is capable of reproducing results for several problems with known solutions.The model was developed using available geometric and hydraulic parameter data and calibrated using hydraulic …

Hollow-Electrode Pulsed Plasma Deposition Of Titanium And Carbon Thin Films, Robert H. Hyde

USF Tampa Graduate Theses and Dissertations

This thesis presents a study of a pulsed distributed arc plasma deposition method that has been developed to produce highly ionized pulsed plasma plumes of metallic species in the presence of a low-pressure inert or reactive gas glow discharge. A pulse-forming network (PFN) is used to form a transient electrical discharge in a hollow electrode which is triggered by two different methods; a pulsed CO2 laser or a pulsed high voltage glow discharge. With the PFN charged to a voltage of 70 - 100 VDC, current pulses with peak currents up to 3 kA and pulse widths as long 3.7 …

Kinematics Of Curved Flexible Beam, Saurabh Jagirdar

USF Tampa Graduate Theses and Dissertations

Compliant mechanism theory permits a procedure called rigidbody replacement, in which two or more rigid links of the mechanism are replaced by a compliant flexure with equivalent motion. Methods for designing flexure with equivalent motion to replace rigid links are detailed in Pseudo-Rigid-Body Models (PRBMs). Such models have previously been developed for planar mechanisms. This thesis develops the first PRBM for spherical mechanisms. In formulating this PRBM for a spherical mechanism, we begin by applying displacements are applied to a curved beam that cause it todeflect in a manner consistent with spherical kinematics. The motion of the beam is calculated …

Tampa’S Lafayette Street Bridge: Building A New South City, Lucy D. Jones

USF Tampa Graduate Theses and Dissertations

The late nineteenth and early twentieth century was a time of dynamic social and political change for Tampa, a growing city on Florida's west coast. These changes led Tampa's commercial-civic elite to look beyond the law, the militia, and the church for ways to maintain their sense of order. This thesis illustrates non-violent enforcement of the status quo via public works, specifically bridge construction over the Hillsborough River. Over a period of three decades, three different bridges were built at the same place, at Lafayette Street. Each time the bridge was built or replaced, it was ostensibly for a different …

A Comparability Analysis Of The National Nurse Aide Assessment Program, Peggy K. Jones

USF Tampa Graduate Theses and Dissertations

When an exam is administered across dual platforms, such as paper-and-pencil and computer-based testing simultaneously, individual items may become more or less difficult in the computer version (CBT) as compared to the paper-and-pencil (P&P) version, possibly resulting in a shift in the overall difficulty of the test (Mazzeo & Harvey, 1988). Using 38,955 examinees' response data across five forms of the National Nurse Aide Assessment Program (NNAAP) administered in both the CBT and P&P mode, three methods of differential item functioning (DIF) detection were used to detect item DIF across platforms. The three methods were Mantel-Haenszel (MH), Logistic Regression (LR), …

Spring Break: Image, Identity, And Consumer Culture In A Florida Rite Of Passage, Meeghan Kane

USF Tampa Graduate Theses and Dissertations

This thesis is a social history of spring break, examining the economic and social aspects of this youth culture phenomenon in Florida. Spring break follows the evolution of youth culture's increasingly complex relationship with an expanding consumer culture. I am exploring its many manifestations in music, film, and popular fiction, but also its rebellious expressions in the riots and arrests on Florida's beaches. I intend to focus on the small beach communities that were transformed by spring break, particularly Fort Lauderdale.Spring break in Florida dates back to the late 1920s in Palm Beach. Wealthy New England families spent their winters …

Practical Applications Of Molecular Dynamics Techniques And Time Correlation Function Theories, Christina Ridley Kasprzyk

USF Tampa Graduate Theses and Dissertations

The original research outlined in this dissertation involves the use of novel theoretical and computational methods in the calculation of molecular volume changes and non-linear spectroscopic signals, specifically two-dimensional infrared (2D-IR) spectroscopy. These techniques were designed and implemented to be computationally affordable, while still providing a reliable picture of the phenomena of interest. The computational results presented demonstrate the potential of these methods to accurately describe chemically interesting systems on a molecular level. Extended system isobaric-isothermal (NPT) molecular dynamics techniques were employed to calculate the thermodynamic volumes of several simple model systems, as well as the volume change associated with …

Investigations Of Fiber Optic Temperature Sensors Based On Yb:Y3Al5O12, Jermaine L. Kennedy

USF Tampa Graduate Theses and Dissertations

This dissertation presents the development of temperature sensors which employ a fiber-optic probe consisting of single crystal YB3BAlB5BOB12B (YAG) fiber with a phosphor of short length grown directly onto one end using the laser heated pedestal growth method. The response of all the crystalline temperature sensors derives from the temperature-dependent decay time of fluorescence. Yb3+P ions served as the fluorescer, while the addition of various rare-earth codopants (i.e., NdP3+ and ErP3+) with YbP3+ provided an additional path in the form of phonon assisted energy transfer. With the additional nonradiative decay path, the temperature sensors exhibited a more desirable response. A …

Tropical Atlantic And Caribbean Climate Variations During The Past Eight Centuries, Kelly Halimeda Kilbourne

USF Tampa Graduate Theses and Dissertations

The Caribbean Sea is a key region from which to generate paleoclimate records because instrumental temperature data indicate that surface temperatures in the Caribbean region are correlated with global surface temperature. Heat and salt fluxes in the Caribbean have been implicated in major reorganizations in Atlantic Meridional Overturning Circulation on glacial time scales [Schmidt et al., 2004] and it has been proposed that the Tropical Atlantic (including the Caribbean Sea) may play a role in smaller-scale changes in the Atlantic basin [Vellinga and Wu, 2004]. A theme of past Caribbean paleoclimate research has been to hypothesize about the interaction between …

Structured Light For Three-Dimensional Microscopy, Leo G. Krzewina

USF Tampa Graduate Theses and Dissertations

The conventional light microscope is an indispensable tool for many physical and life science applications, but is of limited usefulness for three-dimensional imaging due to its increasingly narrow depth of field at high magnifications. Focused regions may be obscured by defocused neighbors or noise from extraneous light sources and subsurface scattering. By rejecting light originating from outside the depth of focus it is possible to minimize these problems. When a contiguous series of such focused slices, or optical sections, are obtained along an axis of an extended object they may be combined to form a complete, focused three-dimensional surface image. …

Part-Time Faculty Job Satisfaction: A Study Of The Influence Of Instructional Technology On Part-Time Faculty In Post-Secondary Institutions, John P. Kurnik

USF Tampa Graduate Theses and Dissertations

In 1990, two-year colleges nationwide reported that approximately 38% of their faculty were part-time. According to the National Center for Educational Statistics' (NCES) 1999 National Study of Post-Secondary Faculty (NSOPF), this percentage continues to rise, and currently exists at 40% or more in some two-year and four-year institutions. To retain competent, qualified, and successful teachers, it is critical for higher education administrators to determine factors that may contribute to part-time faculty's job satisfaction. This study investigated whether the use of instructional technology for curriculum delivery affected part-time faculty job satisfaction by investigating four specific areas that may be affected. The …

Variation In Pediatric Gastroenteritis Admissions Among Florida Counties, 1995-2002, Jean Lee

USF Tampa Graduate Theses and Dissertations

Background: Hospitalizations for pediatric gastroenteritis are considered potentially avoidable and are used to monitor access and quality of primary care for children. Previous reports have found pediatric gastroenteritis admissions higher in Florida compared to the South and the nation.Purpose: The purpose of this project was to explore variation in county admission rates for pediatric gastroenteritis related to non-clinical factors in Florida during 1995-2002. Specific aims included identifying the unique contributions of county socioeconomic characteristics and availability of primary care resources to annual county pediatric gastroenteritis hospital admission rates. Method: The study was retrospective and longitudinal assessing variation in annual county …

Measuring Social Stressors In Organizations: The Development Of The Interpersonal Conflict In Organizations Scale (Icos), Valentina Bruk Lee

USF Tampa Graduate Theses and Dissertations

Interpersonal conflict in organizations has been recognized as a leading social stressor across occupations with detrimental effects on employee well-being and organizational outcomes. However, reliable and valid measures of conflict are scarce and even the most widely used scales are limited by weaknesses in construct definition. In order to address the need for an improved measurement tool, the 63-item Interpersonal Conflict in Organizations Scale (ICOS) was developed. The ICOS was based on a comprehensive conceptualization of conflict that defines the construct on the basis of three definitional components: disagreement, interference, and negative emotion (Barki & Hartwick, 2004). In addition, the …

The Signature Poetics Of Sharon Olds And John Cage, Walter E. Lewallen

USF Tampa Graduate Theses and Dissertations

This dissertation studies and applies the signature theory of Jacques Derrida to two American poets, Sharon Olds and John Cage. I begin by looking at the two texts by Derrida that most closely apply signature theory to poetics: Glas and Signsponge. Along the way, I narrow the scope of Derrida's writing somewhat by focusing on psychoanalytic aspects that relate to Jacques Lacan's ideas and to the concept of the superego. From this work I isolate some protocols for reading, which are then used to study Olds and Cage, two poets who have clearly developed their own signature styles. Here are …

Saharan Dust And Phosphatic Fidelity: A Three Dimensional Biogeochemical Model Of Trichodesmium On The West Florida Shelf, Jason M. Lenes

USF Tampa Graduate Theses and Dissertations

The availability of iron within the surface waters of the broad, oligotrophic West Florida shelf (WFS) controls periodic blooms of the pelagic marine cyanobacterium Trichodesmium. Summer delivery of iron (Fe), in the form of Saharan dust, alleviates this growth constraint, shifting limitation to the efficiency of phosphorus (P) cycles. Florida's rivers drain Miocene phosphorus deposits to supply the WFS with freshwater nutrient supplies at molar dissolved inorganic nitrogen/phosphate (DIN/PO4) ratios of less than 6. These diazotrophs draw upon ubiquitous stocks of dissolved nitrogen gas, once stimulated by Fe-deposition within P-replete waters of the West Florida shelf. An extensive in situ …

Evaluation Of The Operational Effects Of U-Turn Movement, Pan Liu

USF Tampa Graduate Theses and Dissertations

In Florida, the increased installation of non-traversable medians and directional median opening has produced an increased number of U-turns on multilane highways. Arguments have been advanced by some opponents of median modification projects that the increased numbers of U-turns may result in safety and operational problems on multilane highways. The primary objective of this study is to evaluate the operational effects of U-turn movement on multilane roadways. To achieve this research objective, extensive data were collected. Field measurements were conducted at 40 sites in the Tampa Bay area of Florida to collect traffic operations data. Besides, the crash histories of …

Electrically Charged Sol-Gel Coatings For On-Line Preconcentration And Analysis Of Zwitterionic Biomolecules By Capillary Electrophoresis, Wen Li

USF Tampa Graduate Theses and Dissertations

Novel on-line methods are presented for the extraction, preconcentration and analysis of zwitterionic biomolecules using sol-gel-coated columns coupled to a conventional UV/visible detector. The presented approaches do not require any additional modification of the commercially available standard CE instrument. Extraction, stacking, and focusing techniques were used in the preconcentration procedures. The positively charged sol-gel coatings were created using N-octadecyldimethyl[3-(trimethoxysilyl) proply]ammonium chloride (C18-TMS) in the coating sol solutions. Due to the presence of a positively charged quaternary ammonium moiety in C18-TMS, the resulting sol-gel coating carried a positive charge. The negatively charged sol-gel coatings were due to the presence of sulfonate …

Copper And Iron Complexes Of Linear And Crosslinked Polymers As Catalysts For Phosphoester Hydrolysis And Oxidative Transformation Of Phenolic And Catecholic Substrates, Vasiliki Lykourinou

USF Tampa Graduate Theses and Dissertations

The goal of this study is to utilize polymers as macromolecular ligands for the construction of catalysts by formation of coordination complexes with transition metals with the main focus on complexes of Cu(II) and Fe(III) and further determine (a) their catalytic efficiency (b) mechanism of action (c) similarities to enzymatic systems and synthetic metal complexes. The reactions of interest are (1) hydrolytic cleavage of a series of phosphoesters(2) oxidation of catechol type of substrates (3) hydroxylation of phenolic substrates and chlorinated phenols (4) activation of molecular oxygen and/ or hydrogen peroxide (5)oxidative cleavage of DNA plasmid.

The major premise of …

The Role Of The Home Literacy Environment In The Development Of Early Literacy Skills And School Readiness In Kindergarten Children From Low Socioeconomic And Minority Families, Nicole R. Martin

USF Tampa Graduate Theses and Dissertations

The present study investigated the relationship between two predictor variables and children's Dynamic Indicators of Basic Literacy Initial Sound Fluency (ISF) and Letter Naming Fluency (LNF) scores, as well as Early Screening Inventory-Kindergarten (ESI-K) scores. The two predictor variables were 1) parents' perception of their home literacy environment, and 2) parental beliefs about the importance of literacy (race had to be dropped out of the study due to the limited amount of participants per race variable). The participants were 68 kindergarten students and their parents from two schools in a school district in West Central Florida. Results showed that the …

Quantitative Biological Microscopy By Digital Holography, Christopher J. Mann

USF Tampa Graduate Theses and Dissertations

In this dissertation, improved techniques in digital holography, that have produced high-resolution, high-fidelity images, are discussed. In particular, the angular spectrum method of calculating holographic optical field is noted to have several advantages over the more commonly used Fresnel transformation or Huygens convolution method. It is observed that spurious noise and interference components can be tightly controlled through the analysis and filtering of the angular spectrum. In the angular spectrum method, the reconstruction distance does not have a lower limit, and the off-axis angle between the object and reference waves can be lower than that of the Fresnel requirement, while …

Examining The Characteristics Of Teachers In A Master Of Arts In Teaching (Mat) Program In Varying Exceptionalities: Responding To The “Highly Qualified” Teacher Mandate, Erica Djuan Mccray

USF Tampa Graduate Theses and Dissertations

The No Child Left Behind Act of 2001 (2002) mandated that every teacher be highly qualified by the close of the 2005-2006 school year. However, the means by which newly certified teachers are prepared has been questioned. In addition to understanding how teachers enter the field, researchers have indicated a vested interest in examining who comes into the field. More specifically, the characteristics and experiences of pre-service and in-service special educators are of great interest (McKlesky & Ross, 2003; Rosenberg & Sindelar, 2001). The present study examined the characteristics of six teachers in the final internship phase of a Master …

The Effects Of American Diabetes Association (Ada) Diabetes Self-Management Education And Continuous Glucose Monitoring On Diabetes Health Beliefs, Behaviors And Metabolic Control, Jodee Meisenhelder-Smith

USF Tampa Graduate Theses and Dissertations

The purpose of this study was to determine whether adults with type 2 diabetes participating in American Diabetes Association (ADA) diabetes self-management education (DSME) randomly assigned to an intensive follow-up group (IFG), utilizing continuous glucose monitoring system (CGMS), or a standard follow-up group (SFG) have any significant differences in mean HgbA1c values and health belief scores over time. Baseline HgbA1c values and health beliefs were measured using the revised Expanded Health Belief Model (HBM) questionnaire. The questionnaire measured the 8 HBM domains: perceived susceptibility; severity; treatment benefit; cues to action; motivation; barriers; self-efficacy and structural elements. Twelve weeks after DSME, …

Molecular Simulations Of Pd Based Hydrogen Sensing Materials, Ling Miao

USF Tampa Graduate Theses and Dissertations

Hydrogen sensor technology is a crucial component for safety and many other practical concerns in the hydrogen economy. To achieve a desired sensor performance, proper choice of sensing material is critical, because it directly affects the main features of a sensor, such as response time, sensitivity, and selectivity. Palladium is well-known for its ability to sorb a large amount of hydrogen. Most hydrogen sensors use Pd-based sensing materials. Since hydrogen sensing is based on surface and interfacial interactions between the sensing material and hydrogen molecules, nanomaterials, a group of low dimensional systems with large surface to volume ratio, have become …

Goal Conflicts, Self-Regulation, And Course Completion: A Comparison Of Web-Based Learners To Traditional Classroom Learners, Barbara Moore

USF Tampa Graduate Theses and Dissertations

The purpose of this study was to examine the goal conflicts, self-regulation, and course completion of post-secondary learners and to compare these factors in distance and traditional learners. Participants completed a self-report survey given on-line to those who had Internet access and administered in paper format to students in traditional classrooms. Procrastination, socializing, and employment were the most common goal conflicts reported by participants. Significantly more web-based students than traditional students were employed and were employed more average hours. Web-based students also had more children under the age of 12 than did traditional students. A significantly greater percentage of web-based …

Regression Approach To Software Reliability Models, Abdelelah M. Mostafa

USF Tampa Graduate Theses and Dissertations

Many software reliability growth models have beenanalyzed for measuring the growth of software reliability. In this dissertation, regression methods are explored to study software reliability models. First, two parametric linear models are proposed and analyzed, the simple linear regression and transformed linearregression corresponding to a power law process. Some software failure data sets do not follow the linear pattern. Analysis of popular real life data showed that these contain outliers andleverage values. Linear regression methods based on least squares are sensitive to outliers and leverage values. Even though the parametric regression methods give good results in terms of error measurement …

Generalized Non-Dimensional Depth-Discharge Rating Curves Tested On Florida Streamflow, Auristela Mueses-Pã©Rez

USF Tampa Graduate Theses and Dissertations

A generalized non-dimensional mathematical expression has been developed to describe the rating relation of depth and discharge for intermediate and high streamflow of natural and controlled streams. The expressions have been tested against observations from forty-three stations in West-Central Florida. The intermediate-flow region model has also been validated using data from thirty additional stations in the study area. The proposed model for the intermediate flow is a log-linear equation with zero intercept and the proposed model for the high-flow region is a log-linear equation with a variable intercept. The models are normalized by the depth and discharge values at 10 …

Thermal Analyses Of Hydrophilic Polymers Used In Nanocomposites And Biocompatible Coatings, Kadine Mohomed

USF Tampa Graduate Theses and Dissertations

ABSRACT: This research focuses on two hydrophilic polymers that form hydrogels when they sorb water: Poly(2-hydroxyethyl methacrylate) (PHEMA) and Poly(2,3-dihydroxypropyl methacrylate) (PDHPMA). Present work in the field obviated the need to properly characterize the thermal and dielectric properties of these materials.The dielectric permittivity, e', and the loss factor, e", of dry poly(2-hydroxyethyl methacrylate) and poly(2,3-dihydroxypropyl methacrylate) were measured using a dielectric analyzer in the frequency range of 0.1Hz to 100 kHz and between the temperature range of -150 °C to 275°C. The dielectric response of the sub-Tg gamma transition of PHEMA has been widely studied before but little to no …

The Contribution Of The Neighborhood Context To Social Disparities In Access To Health Care Among Sexually Experienced Adolescent Females, Jodi Nearns

USF Tampa Graduate Theses and Dissertations

Access to health care is an important resource for sexually experienced adolescent females in the prevention of unintended pregnancy and sexually transmitted infections, including HIV. However, a paucity of research exists regarding the extent to which social disparities in access to health care exist among this vulnerable population of adolescents, including the potential contribution of the neighborhood context. Therefore, the primary aims of this dissertation were to examine (1) the extent to which racial and socioeconomic disparities in access to health care exist among sexually experienced adolescent females, (2) the extent to which access to health care among sexually experienced …

A Design Of Experiments Study Of Procedure For Assembling Bascule Bridge Fulcrum, Cuong Q. Nguyen

USF Tampa Graduate Theses and Dissertations

A bascule bridge is a type of movable bridge that can be opened or closed to facilitate the movement of water-borne traffic such as ships and yachts. Trunnion-Hub-Girder (THG) assembly plays a role as a fulcrum in the bascule bridge. To make the fulcrum, the trunnion is shrink-fitted into the hub, and then the trunnion-hub assembly is shrink-fitted into the girder. Hundreds of thousands of dollars could be lost due to failures during this step. Crack formations in the hubs of various Florida bascule bridges during assembly led the Florida Department of Transportation to commission a project with USF professors …

The Information Technology Professional’S Psychological Contract Viewed Through Their Employment Arrangement And The Relationship To Organizational Behaviors, Sandra Kay Newton

USF Tampa Graduate Theses and Dissertations

Information technology (IT) professionals are continually placed in diverse employment arrangements as organizations continually look for ways to cut costs, enhance performance and maximize organizational goals. Organizations are using strategies beyond hiring permanent employees to achieve objectives in alternative sourcing. Even though the cost differential is positive when employing non-permanent individuals instead of permanent employees, little is known about the effects on the IT professional.This field study was designed to test the effects of employment arrangements on the IT professional's psychological contract and the effects of the level of fulfillment of their psychological contract on their organizational citizenship and innovative …