Digital Commons Network^™

Public Opinion And The Introduction Of Congressional Environmental Legislation, 1973-2002, Hugh Eugene Jarvis

USF Tampa Graduate Theses and Dissertations

This study examines the relationship between public opinion about the environment and the introduction of congressional legislation on environmental issues. Using public opinion data gathered by the General Social Survey from 1977 to 2002, this work examines correlations between how the public views the environment in each and the number of bills introduced in the U.S. House and Senate addressing environmental issues. The findings indicate that there is a correlation between overall concern felt in the public and congressional action on certain aspects of environmental protection. The results also highlight the potentially disturbing finding that the race and economic class …

U.S. Based Business Needs For Technical/Occupational Employees With International Skills: Considerations For Community College And Sub-Baccalaureate Programs In The Tampa Bay Economic Zone., Ronald L. Olney

USF Tampa Graduate Theses and Dissertations

Significance: This study provides the first systematic needs assessment of a U.S. business region to determine if businesses want international skills taught in community college technical and occupational programs. Without this assessment, community college leaders and faculty are not able to determine whether they are adequately preparing students in these skills to be successful in tomorrow's fast paced, mobile and integrated global workforce.

Research Aims:

1. Conduct a needs assessment to determine whether international skills were considered important for employment entry or movement

2. Determine where businesses obtain international skills training.

3. Garner business recommendations for the improvement of international …

Development Of Thin Cshso4 Membrane Electrode Assemblies For Electrolysis And Fuel Cell Applications, Lars E. Ecklund-Mitchell

USF Tampa Graduate Theses and Dissertations

In this work the use of the solid acid CsHSO₄ as an electrolyte in a hydrogen/oxygen fuel cell or the disassociation of water into hydrogen and oxygen has been investigated. Several issues have been cited in literature regarding the use of CsHSO₄ as a solid electrolyte; these include: difficulty interpreting proton conductivity profiles of real membranes, high permeability of the membrane to fuel and product gases, and low mechanical strength. In an attempt to improve our understanding and possibly eliminate these issues, performance characteristics of prepared CsHSO₄ membranes have been investigated utilizing various methods of synthesis and …

Resonance Ultrasonic Vibrations And Photoluminescence Mapping For Crack Detection In Crystalline Silicon Wafers And Solar Cells, Andrii Monastyrskyi

USF Tampa Graduate Theses and Dissertations

The solar energy, or photovoltaic (PV) industry, driven by economic competition with traditional fossil energy sources, strives to produce solar panels of the highest conversion efficiency and best reliability at the lowest production cost. Solar cells based on crystalline silicon are currently the dominant commercial PV technology by a large margin, and they are likely to remain dominant for at least one decade. The problem of improvement mechanical stability of silicon wafers and finished solar cell is one of the most critical for entire PV industry. Mechanical defects in wafer and cells in the form of periphery or internal cracks …

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 …

Statistical Profile Generation Of Real-Time Uav-Based Traffic Data, Anuj Puri

USF Tampa Graduate Theses and Dissertations

Small unmanned vehicles are used to provide the eye-in-the-sky alternative to monitoring and regulating traffic dynamically. Spatial-temporal visual data are collected in real-time and they are used to generate traffic-related statistical profiles, serving as inputs to traffic simulation models. Generated profiles, which are continuously updated, are used to calibrate traffic model parameters, to obtain more accurate and reliable simulation models, and for model modifications. This method overcomes limitations of existing traffic simulation models, which suffer from outdated data, poorly calibrated parameters, questionable accuracy and poor predictions of traffic patterns.

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 …

The Effect Of Hydrogen On The Optical, Structural Properties And The Crystallization Of Gete2 Thin Films Prepared By Rf Magnetron Sputtering, Ke Cao

USF Tampa Graduate Theses and Dissertations

Thin films of GeTe₂ were deposited on glass substrates using RF magnetron sputtering with various hydrogen flow rates in the growth chamber. Transmission data of deposited films were taken and used to determine optical constants: refractive index (n), extinction coefficient (κ), and absorption coefficient (α)) and the energies: E₀₄, E₀₃, Tauc band gap E[subscript]Tauc and Urbach energy E[subscript]U. An increase of these energies was observed with increasing hydrogen flow rate. This increase is interpreted on the basis of the density of state model proposed by Mott and Davis. An increase of network disorder due to the inclusion of hydrogen into …

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 …

Active And Passive Microwave Radiometry For Transcutaneous Measurements Of Temperature And Oxygen Saturation, Thomas A. Ricard

USF Tampa Graduate Theses and Dissertations

In this work we explore two novel uses of microwave technology in biomedical applications. Introductory material on the electrical properties of biological tissues is presented to form the groundwork for the basic theory behind both techniques.

First, we develop a technique that uses 60 GHz signals to detect changes in blood oxidation levels. Several atmospheric propagation models are adapted to predict oxygen resonance spectra near this frequency. We are able to predict and observe the changes in these levels as the blood ages up to 48 hours. Identical testing procedures performed using arterial blood gas (ABG) calibration samples with controlled …

Fate Of Volatile Chemicals During Accretion On Wet-Growing Hail, Ryan A. Michael

USF Tampa Graduate Theses and Dissertations

Phase partitioning during freezing of hydrometeors affects the transport and distribution of volatile chemical species in convective clouds. Here, the development, evaluation, and application of a mechanistic model for the study and prediction of partitioning of volatile chemical during steady-state hailstone growth are discussed. The model estimates the fraction of a chemical species retained in a two-phase growing hailstone. It is based upon mass rate balances over water and solute for constant accretion under wet-growth conditions. Expressions for the calculation of model components, including the rates of super-cooled drop collection, shedding, evaporation, and hail growth were developed and implemented based …

The Channel For Gay America? A Cultural Criticism Of The Logo Channel’S Commercial Success On American Cable Television, Michael Johnson Jr.

USF Tampa Graduate Theses and Dissertations

Logo currently holds a self-described monopoly as the "Gay Channel for America." Logo stands alone as the single most concentrated national-level vehicle of LGBT (Lesbian, Gay, Bisexual and Transgendered) visibility in the post millennial television era. The Logo Channel has reaped financial rewards from its strategy as a business entity, as LGBT American television viewers embraced its presence as a signifier to America that gays and lesbians have finally "made it".

First, any claim to a monopoly deserves critical attention for its place in mainstream television, for its business practices, and for the power it holds in representing and targeting …

The Effect Of Multidimensional Information Presentation On The Effectiveness And Efficiency Of A Spatial Accounting Judgment, John K. Tan

USF Tampa Graduate Theses and Dissertations

This study is the first in a series of planned studies on the application of multidimensional visualization of business information and data within the context of accounting. The study's research question is: When is multidimensional visualization of information a better problem representation, improving both the effectiveness and efficiency of a spatial accounting judgment?

To examine when multidimensional visualization can assist auditors in configural cue pattern recognition, the study employs the traditional DuPont analysis as the three pieces of key information to be represented on the X, Y, and Z axes of a single 3-D perspective display. To help determine when …

Directed Self-Assembly Of Gold Nanorods Using Surface Modification, David A. Walker

USF Tampa Graduate Theses and Dissertations

Metallic nanoparticles are unique materials for optical, electronic, catalytic, and sensing applications. Due to the vast flexibility in controlling the surface chemistry of these particles through functionalization there is a great deal of interest in using metallic nanoparticles as building blocks in the development of more complex nanostructures through the use of a 'bottom-up' approach. Using self assembly techniques, one can exploit spontaneous chemical interactions to build complex constructs on the nanometer scale.

Towards this end, gold nanorods have been synthesized and modified with various polymers, inorganic oxides and organic ligands to establish principles for self-assembly of these unique nanomaterials. …

A Biomechanical Evaluation Of A Novel Surgical Reconstruction Technique Of The Ulnar Collateral Ligament Of The Elbow Joint, Nicole Williams

USF Tampa Graduate Theses and Dissertations

The objective of this thesis is to biomechanically evaluate a novel Double bundle technique for UCL reconstruction designed to accelerate recovery time and minimize gap formation. Excluding UCL surgery, ligament reconstruction procedures typically require an average of 6 months of recovery time. UCL reconstructive surgery requires approximately 1-2 years of recovery time. Valgus instability of the elbow is characterized by attenuation, or frank rupture of the UCL from repetitive and excessive valgus loads. This research compared the valgus stability, gap formation, and ultimate strength that resulted from the cyclic valgus loading at 30 ° of flexion of 3 techniques for …

Role Of Foxo Factors As The Nuclear Mediator For Pten-Ar Antagonism In Prostate Cancer Cells, Qiuping Ma

USF Tampa Graduate Theses and Dissertations

FoxO proteins are transcriptional factors acting downstream of the tumor suppressor PTEN. Their activity is negatively regulated by AKT-mediated phosphorylation. Our previous studies showed a mutual suppression between PTEN and the androgen receptor (AR) in regulating growth and apoptosis in prostate cancer (PCa) cells. We hypothesize that nuclear FoxO proteins are involved in mediating this mutual antagonism. In this dissertation, we report that PTEN inhibits AR activity through FoxO1 and provide evidence for the involvement of FoxO factors in the androgen-mediated suppression of PTEN-induced apoptosis. Our studies identify a novel mechanism for AR inhibition by FoxO1 and demonstrated the participation …

Structural Diversity In Metal-Organic Materials, Gregory J. Mcmanus

USF Tampa Graduate Theses and Dissertations

The interest in metal-organic materials namely, coordination polymers and metal-organic frameworks has risen dramatically over the past few years. To a certain extent this interest is a consequence of the realization chemists have discovered how to play a form of molecular Lego® in which metal cations or metal clusters represent the bricks (or nodes) and organic ligands such as 4,4-bipyridine (bipy) or benzene-dicarboxylate represents the glue (or spacers). The "node-and-spacer" approach to self-assembly can be invoked in such a manner that a plethora of infinite architectures and discrete polyhedra can be generated from geometric principles, some of which are unprecedented …

Mechanical Properties Of Particulate-Reinforced Boron Carbide Composites, Lorenzo W. Hankla

USF Tampa Graduate Theses and Dissertations

The mechanical properties of boron carbide (B₄C) with 10 and 20 vol% particulate inclusions of commercially available nano-sized alpha-phase silicon carbide (a-SiC) or micron-sized titanium diboride (TiB₂) were investigated so as to produce a fine-grained material with high hardness, toughness, and overall strength in order to increase the effectiveness of B₄C as a structural ceramic, whose use in the field has been limited because of the extreme brittle nature of the material.

Full density sintering of the ceramics (≥99% theoretical) was completed using the novel Plasma Pressure Compaction (P²C®) technique, which limited grain growth …

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 …

Sustainable Control Of Ascaris Lumbricoides (Worms) In A Rural, Disease Endemic And Developing Community: A Systems Approach, Monica Annmarie Gray

USF Tampa Graduate Theses and Dissertations

Parasitic infections, inadequate sanitation, and poor nutrition represent major etiologies that operate in synergy to cause some of the world's most disabling diseases. Citizens of developing nations, especially children living in rural areas, are the most affected. Current research and subsequent interventions have attempted to solve these issues using vertical interventions aimed at minimizing specific health outcomes. This approach does not consider the interaction among causes and the interrelationship between human beings and their environment. Challenges solved in this manner often fail to produce sustainable results or worse, create new problems.

This project proposed the systems approach framework to address …

Background Subtraction Using Ensembles Of Classifiers With An Extended Feature Set, Brendan F. Klare

USF Tampa Graduate Theses and Dissertations

The limitations of foreground segmentation in difficult environments using standard color space features often result in poor performance during autonomous tracking. This work presents a new approach for classification of foreground and background pixels in image sequences by employing an ensemble of classifiers, each operating on a different feature type such as the three RGB features, gradient magnitude and orientation features, and eight Haar features. These thirteen features are used in an ensemble classifier where each classifier operates on a single image feature. Each classifier implements a Mixture of Gaussians-based unsupervised background classification algorithm. The non-thresholded, classification decision score of …

A Stressor-Strain Model Of Organizational Citizenship Behavior And Counterproductive Work Behavior, Kimberly E. O'Brien

USF Tampa Graduate Theses and Dissertations

Prior research has attempted to develop a model of organizational citizenship behaviors (OCB) and counterproductive work behaviors (CWB), but limited testing remains a problem. The purpose of the current study is to examine OCB and CWB from a job stressor-strain approach. The sample consisted of 235 employees throughout the United States and their supervisors. Results of the study suggested OCB and CWB are affected by stressors (including interpersonal conflict, low interactional justice, job demands, and organizational constraints). Additionally, trait emotion and attributional styles affect the amount of stressors perceived. The implications as well as limitations of the study are discussed.

Orbital- To Millennial-Scale Variability In Gulf Of Mexico Sea Surface Temperature And Salinity During The Late Pleistocene, Jessica L. Whitaker

USF Tampa Graduate Theses and Dissertations

Sea surface temperature (SST) reconstructions from the low latitudes indicate the tropics/subtropics warmed significantly before glacial-interglacial decreases in global ice volume, suggesting the importance of tropical and subtropical climate in driving glacial terminations.

ODP Site 625, drilled at a water depth of 889 m near De Soto Canyon in the Gulf of Mexico (GOM), provides continuous records of marine isotope stages (MIS) 1-6 sampled at a mean temporal resolution of 400 years. Age control is based on 8 AMS radiocarbon dates, marine isotope stratigraphy, and Foraminifera datum levels. Results from Globigerinoides ruber (white variety) Mg/Ca-SST indicate a rise of 4.4 …

Remote Monitoring Systems For Substructural Health Monitoring, Jonathan D. Collins

USF Tampa Graduate Theses and Dissertations

Remote Wireless Monitoring Systems have made a large impact in the area of Structural Health Monitoring. However in the specialized sub-field of Substructural Health Monitoring, remote monitoring techniques have not made as much headway. First, monitoring systems are often retrofitted onto a structure. Therefore it is much harder to retrofit the substructure of a bridge or building. Second, many foundation elements such as driven piles or auger-cast piles are constructed in a way that makes installation difficult or can severely damage the sensing materials.

This thesis presents two case studies of Remote Monitoring Systems for Substructural Health Monitoring applications 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 …

Location Awareness In Cognitive Radio Networks, Hasari Celebi

USF Tampa Graduate Theses and Dissertations

Cognitive radio is a recent novel approach for the realization of intelligent and sophisticated wireless systems. Although the research and development on cognitive radio is still in the stage of infancy, there are significant interests and efforts towards realization of cognitive radio. Cognitive radio systems are envisioned to support context awareness and related systems. The context can be spectrum, environment, location, waveform, power and other radio resources. Significant amount of the studies related to cognitive radio in the literature focuses on the spectrum awareness since it is one of the most crucial features of cognitive radio systems. However, the rest …

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 …

A 1400 Year Multi-Proxy Record Of Hydrologic Variability In The Gulf Of Mexico: Exploring Ocean-Continent Linkages During The Late Holocene, Jennifer A. Flannery

USF Tampa Graduate Theses and Dissertations

Late Holocene climate variability includes the Little Ice Age (LIA, 450-150 BP) and the Medieval Warm Period (MWP, 1100-700 BP) that are characterized by contrasting hydrologic and thermal regimes. The degree of interaction between the North American continent and the ocean during these two abrupt climate events is not well known. Marine sedimentary records from basins proximal to major rivers integrate climate signals across large spatial scales and can provide a coherent, high-resolution assessment of the oceanic and continental responses to changing climate and hydrologic conditions. The Pigmy Basin in the northern Gulf of Mexico is ideally situated to record …