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A Pseudo-Rigid-Body Model For Spherical Mechanisms: The Kinematics And Elasticity Of A Curved Compliant Beam, Alejandro Leã³N

USF Tampa Graduate Theses and Dissertations

This thesis improves a previous kinematic analysis and develops the elastic portion of the analysis of a curved compliant beam. This analysis is used to develop a Pseudo-Rigid-Body Model for the curved compliant beam. The Pseudo-Rigid-Body Model consist of kinematic and elastic parameters which can be used to simplify the computation of the large deflections of the beam as it undergoes spherical motion. The kinematic parameters that are developed are the characteristic radius, Gamma*length, the parametric angle coefficient, c_theta, and the kinematic parametrization limit, Capital_theta_max(Gamma). The elastic parameters developed are the stiffness coefficient, K_theta, and the elastic parameterization limit, Capital_theta_max(K). …

Transient Fluorescence Spectroscopy And Laser Induced Fluorescence Lifetimes Of Terbium Doped Dipicolinic Acid, Anali Makoui

USF Tampa Graduate Theses and Dissertations

We have investigated the use of deep UV laser induced fluorescence for the sensitive detection and spectroscopic lifetime studies of terbium doped dipicolinic acid (DPA-Tb) and used this to study the optical characteristics of DPA which is a chemical surrounding most bacterial spores. Background absorption spectra, fluorescence spectra, and Excitation Emission Matrix (EEM) spectra were made of the DPA-Tb complex, using both fixed 266 nm wavelength and tunable (220 nm --

280 nm) UV laser excitations. Of importance, the fluorescence lifetimes of the four main fluorescence peaks (488 nm, 543 nm, 581 nm, and 618 nm) of the DPA-Tb complex …

Getting It Right: A Story Of Truth In Music Performance, Christopher Mcrae

USF Tampa Graduate Theses and Dissertations

This project looks at the relationship between music performance and truth in narrative. Music performance is a fluid and dynamic process with complex and multiple relationships among musician, audience, text, and production. The five sections of this thesis discuss five different musical performances that address different aspects of this dynamic process. I look at the relationship between music performance and Performance Studies, issues of personae and presence, questions of identity and masculinity, pedagogy and performance, and the intersections of writing and performance. The five musical performances in this project are written to not only discuss important aspects of music and …

Self Assembly Of Complex Structures, Michael Nellis

USF Tampa Graduate Theses and Dissertations

The state of the art in artificial micro self assembly concepts are reviewed. The history of assembly is presented with a comparison to macro assembly, which has been widely studied, and micro self assembly. Criteria were developed and tested to show that macro assembly is more complex in ways that micro self assembly is not. Self assembly requirements for successful and complex self assembly, which evolved from the macro and micro comparison, are also established and tested. A method to assemble complex structures in the micro scale is proposed and demonstrated at the meso scale. The basic concepts of self …

Effects Of Corrosion On Steel Reinforcement, David Ostrofsky

USF Tampa Graduate Theses and Dissertations

Corroded steel in concrete is a structural issue that plaques concrete structures in coastal regions. Traditionally corroded steel strength is calculated from a distributed area loss due to corrosion over the entire surface of the steel and reducing the capacity accordingly. In reality, corrosion attacks localized regions creating pits and reducing the cross section in a small region which amplifies the effects of corrosion. Stress concentrations at the corrosion pitting damage may further reduce the tensile capacity of the steel. A study of corrosion damage and strength associated with pitting damage can assist in understanding the ultimate tensile capacity of …

Safety Impacts Of Right Turns Followed By U-Turns, Fatih Pirinccioglu

USF Tampa Graduate Theses and Dissertations

The objective of this study was to determine the safety impacts of right turn followed by U-turn movements (RTUT) at signalized intersections as well as median openings. RTUT movements are the most common alternatives to direct DLT movements(DLT). In order to achieve such data in a shorter amount of time, conflict analysis was chosen to be useful in this study as opposed to crash analysis. Additionally, data collection sites were divided dependent on certain geometric criterion and conflict data was recorded by the use of video recording equipment. Seven out the eleven conflict types used during the study were related …

Factors Perceived To Contribute To Mathematics Avoidance Or Mathematics Confidence In Non-Traditional Age Women Attending A Community College, Jo Ann K Rawley

USF Tampa Graduate Theses and Dissertations

Over the past decade, the number of students entering postsecondary institutions immediately after high school has been decreasing, while the number of non-traditional aged students, defined as adults over 25, has substantially increased, with women making up the majority of this adult student group. Mathematics education is an area where non-traditional age women tend to have difficulty. Fifteen individual interviews were conducted with non-traditional age women enrolled in a community college, 10 identifying mathematics as the subject they would least enjoy and 5 identifying mathematics as the subject they would most enjoy. Data were analyzed by comparing the women's stories …

Manifestations Of Ebenezer Howard On Disneyland, Michelle M. Rowland

USF Tampa Graduate Theses and Dissertations

While political praise and condemnation of Disney is commonplace in the literature, my research will focus instead on the origination of Disney's design plan for Disneyland and the theoretical and physical connections between key historical figures and the finished product. I will not consider what Disneyland means to the world today---that is a subject many others have covered, some even brilliantly; instead, I will consider what social concepts contributed to the initial design in an attempt to see the underlying values at work in this post-modern utopia. In this thesis, I intend to show that Walt Disney's initial design for …

Credibility Perceptions Of Television And Online News, Charmy G. Sabigan

USF Tampa Graduate Theses and Dissertations

Three major factors influence audience's credibility perception of mediated news on television and on the internet. This study found that reporters' credibility, media credibility, and news credibility had direct influence to the credibility of news presented on both media. Reporters' credibility on both media could be measured by their expertise, intelligence, education, trustworthiness, and authoritativeness. Television and the internet were evaluated differently. Television was measured by its comprehensiveness, concern for the interest of the public, and fairness. The internet was assessed on its trustworthiness, consideration of public interest, and objectivity. News credibility for both media, however, could be evaluated using …

In-Vivo Radiation Diode Dosimetry For Therapeutic Photon Beams, Amarjit Singh Saini

USF Tampa Graduate Theses and Dissertations

In-vivo dosimetry with diode detectors is used in radiation therapy as a quality assurance tool. The diode sensitivity under radiation depends upon temperature, dose rate and SDD (source-to-detector distance), field size, beam angle, and energy. This dissertation presents the first systematic and quantitative study of dosimetric characteristics for most of the commercial radiation diodes (n-type and p-type) under different radiation beams.In the temperature dependence study, the systematic study on the dose rate dependence of svwt (sensitivity variation with temperature) was performed. It was concluded that sufficient preirradiation can eliminate dose rate dependence of svwt. However, preirradiation cannot eliminate dose rate …

Methods To Improve Bond On Frp Wrapped Piles, Andy Schrader

USF Tampa Graduate Theses and Dissertations

Fiber Reinforced Polymer (FRP) sheets can provide incredible structural strength while weighing only a fraction as much as steel. When applied to piles the FRP provides strengthening through both concrete confinement and tensile reinforcement. Mainly used in structural repair, its application is relatively simple in theory. However, many factors(some avoidable, some not) can interfere with the bond between FRP and concrete. When this bond is interrupted the strength of the repair becomes compromised.This thesis examines 2 new methods of improving FRP bond to concrete piles during the time the resin is curing. These methods are compared using 3 types of …

Vadose Zone Processes Affecting Water Fluctuations: Conceptualization And Modeling Considerations, Nirjhar Shah

USF Tampa Graduate Theses and Dissertations

This dissertation focuses on a variety of vadose zone processes that impact water table fluctuations. The development of vadose zone process conceptualization has been limited due to both the lack of recognition of the importance of the vadose zone and the absence of suitable field data. Recent studies have, however, shown that vadose zone soil moisture dynamics, especially in shallow water table environments, can have a significant effect on processes such as infiltration, recharge to the water table, and evapotranspiration. This dissertation, hence, attempts to elucidate approaches for modeling vadose zone soil moisture dynamics. The ultimate objective is to predict …

Changes In Abundance And Distribution Of Humpback Whales, Megaptera Novaeangliae, In Hervey Bay Marine Park, Australia, Based On Aerial Surveys Conducted In 1992 And 2004, Lucã­A De La Paz Suzacq

USF Tampa Graduate Theses and Dissertations

Aerial surveys were conducted throughout Hervey Bay Marine Park between August and October 1992 and 2004 to determine changes in abundance and distribution of the Eastern Australia humpback whale population in this area. Due to concerns about possible effects of boat traffic on whale distributions associated with a growing whale watching industry, the number and location of vessels were also recorded during these surveys. Throughout the 1992 season, 17 flights were conducted and a total of 41.93 surveys hours were completed, recording 186 pods, and a total of 320 animals. In addition, 392 boats were spotted in the area. During …

Assessing The Reproducibility Of Skeletal Geochemistry Records In Atlantic Corals Using Montastraea Annularis Coral Heads From The Dry Tortugas, Florida, Kristine L. Stair

USF Tampa Graduate Theses and Dissertations

Core samples were collected in September 1995 from live coral heads of Montastraea annularis at Bird Key reef in the Dry Tortugas, Florida (24 degrees 55 minutes N, 82 degrees 92 minutes W). Four 4 mm-thick coral slabs from two cores were continuously sampled at 12 samples per year (0.025 cm per sample for Core 31, 0.023 cm per sample for Core 35). Visual inspection of X-radiographs indicates an average skeletal extension rate of about 3 mm per year in Bird Key corals. The goal of this study was to perform a replication test in Montastraea annularis by using elemental …

Cellular Electrofusion Utilizing Corona Fields And Dc Pulse Technology, Joshua Stein

USF Tampa Graduate Theses and Dissertations

Cell fusion is an important technique that is used in the field of medicine and biomedical research. For instance, fusion can be used to create hybridomas and novel types of secretory hybrid cells. It may also be used to engineer cultured insulin-secreting pancreatic B-cell lines for the treatment of diabetes. Historically, the applications listed above have been accomplished by a number of methodologies including dielectrophoresis, centrifugation, polyethylene glycol (PEG) and viral fusion proteins. However, these approaches often fail to produce the desired results due to poor cell viability, lack of 1:1 fusion, and use of non-physiological environments. It is proposed …

Technology And Older Faculty: A Descriptive Study Of Older Florida Community College Faculty, Christopher D. Van Der Kaay

USF Tampa Graduate Theses and Dissertations

Institutions of higher learning across the United States are experiencing an aging faculty population. A significant proportion of college and university faculty are over 55, a growth expected to continue in future years. Parallel to this growth and change has been an expanding use of technology in higher education. Despite this trend and potential implications, few studies have provided in-depth insight into older faculty and technology. The study used a quantitative descriptive design to provide a comprehensive look at older community college faculty and various aspects of technology. Areas examined included older faculty's perceptions of technology, their attitudes toward institutional …

Experimental And Analytical Modeling Of The In Vivo And In Vitro Biomechanical Behavior Of The Human Lumbar Spine, Tov I. Vestgaarden

USF Tampa Graduate Theses and Dissertations

This dissertation has two major parts; Analytical and Experimental. The analytical section contains a study using Finite Element Analysis of dynamic instrumentation to demonstrate stress reduction in adjacent level discs. The experimental section contains biomechanical testing of facet fusion allograft technique and finally a comparison between In Vivo and In Vitro intradiscal pressures to determine forces acting on Lumbar spine segment L4-L5. A comprehensive study of available data, technology and literature was done. Conventional fusion instrumentation is believed to accelerate the degeneration of adjacent discs due to the increased stresses caused by motion discontinuity. A three dimensional finite element model …

Pneumatic Tool Hand-Arm Vibration And Posture Characterization Involving U.S. Navy Shipboard Personnel, Charles R. Wilhite

USF Tampa Graduate Theses and Dissertations

The United States Navy incorporates many different occupations to ensure it achieves its overall mission. These occupations are extremely diversified and present a wide spectrum of occupational exposures. Many of these exposures have been well studied and documented. However, shipboard pneumatic tool hand-arm vibration, (HAV) and how it relates to different body postures is an area of occupational exposure that has received little attention. The chief objective of this study was to assess whether there is a difference in hand-arm vibration levels, while working on one of two surface orientations (e.g., horizontal and vertical) among distinctly different pneumatic tools while …

Graduate Students/Mothers Negotiating Academia And Family Life: Discourses, Experiences, And Alternatives, Shirlan A. Williams

USF Tampa Graduate Theses and Dissertations

This study examines the experiences and perceptions of graduate students who are mothers. Based on discourse analysis, one-on-one interviews, and focus groups, this study argues that institutional discourses and practices place graduate students who are mothers in untenable and irreconcilable positions between "mom" and "student," between "family" and "the academy," between "self" and "success." These irreconcilable differences are created in discourse, enacted in institutional policies, and lived by the participants. The study offers action-based alternatives to the status quo policies of the university based on the self-described needs of these women. It reveals that support from all fronts--the home, the …

Modeling Considerations For Vadose Zone Soil Moisture Dynamics, Jing Zhang

USF Tampa Graduate Theses and Dissertations

Reproducing moisture retention behavior of the upper and lower vadose zone in shallow water table settings provides unique challenges for integrated (combined surface and groundwater) hydrological models. Field studies indicate that moisture retention in shallow water table settings is highly variably affected by antecedent state and air entrapment. The theory and vertical behavior of a recently developed integrated surface and groundwater model (IHM) is examined through comparisons to collected field data in West-Central Florida. The objectives of this study were to (1) Identify important considerations and behavior of the vadose zone for reproducing runoff, ET and recharge in shallow water …

Awakening Days At Dead River, Edward Curry Woodward

USF Tampa Graduate Theses and Dissertations

Awakening Days at Dead River traces the history of a remote public park in north Hillsborough County that was once a privately-owned riverside enclave with modest cabins, and home to a popular fish camp on the Hillsborough River. The timeframe focuses on the mid-twentieth century to present, with a contextual background of earlier history in the immediate area. The story recounts the adventures and challenges of a select group of homeowners and visitors who experienced life on the Hillsborough and Dead Rivers during that timeframe. It also shows how the area evolved into a public property when regional flood control …

Design Of Metal-Organic Framework Materials Based Upon Inorganic Clusters And Polycarboxylates, Zhenqiang Wang

USF Tampa Graduate Theses and Dissertations

Network structures based upon metal-organic backbones represent a new class of functional materials that can be rationally constructed by employing the concepts of supramolecular chemistry and crystal engineering. The modularity of design strategies, the diversity of prototypal structures, and the dynamic features of networks have afforded great advantages over traditional materials syntheses. The research presented in this dissertation is primarily concerned with developing an in-depth understanding of the basic principles that govern the supramolecular behaviors of metal-organic frameworks and gaining an experimental control over the structure and function of these new classes of hybrid materials.

The use of rigid and …

Low Voltage Electrochemical Hydrogen Production, Eric P. Weaver

USF Tampa Graduate Theses and Dissertations

Hydrogen production is dependent on natural gas, 90% in the U.S. and 48% of the world’s production. Natural gas supply is dwindling and it’s price is increasing. Greenhouse gases and air pollutants are emitted when natural gas is used. In a single product production facility, coal is not competitive with natural gas for hydrogen production at current prices. Hydrogen production by direct electrochemical dissociation of water requires a relatively high voltage.

Techniques have been developed for manufacturing hydrogen as a lucrative byproduct of IGCC electric power generation, refinery sulfur production and sulfuric acid production for fertilizer production. Laboratory experiments have …

A Comparison Of The Perceived Performance Of Mentoring Functions Of National Boardcertified And Non-National Board-Certified Teachers With Their Protégés, Amy Jo Smith Wilson

USF Tampa Graduate Theses and Dissertations

National Board-certified (NBC) teachers are recognized as accomplished teachers who have met the National Board’s stringent standards. These teachers are encouraged to serve as mentors to novice teachers and veteran teachers in candidacy for National Board Certification. This study identified and compared the career and psychosocial mentoring functions that NBC teacher mentors and non-NBC teacher mentors perceived they provided to their protégés at the elementary grade levels. National Board-certified protégés’ perceptions of having the functions provided were compared with those of their teacher mentors and with the protégés of non-NBC teacher mentors.

The research was conducted in a large urban …

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 …

Hydrogen Isotopic Ratios Of Algal And Terrestrial Organic Matter In Lake Tulane, Florida: From A Modern Calibration To The Reconstruction Of Paleoclimatic And Paleohydrologic Conditions, Eric Charles Cross

USF Tampa Graduate Theses and Dissertations

Recent sedimentary records have indicated that climate in low latitude, continental environments have varied significantly throughout the mid to late Holocene. In subtropical North America, major climatic phenomena such as the migration of the Intertropical Convergence Zone (ITCZ) and the Bermuda High have been shown to play a major role in this variability. Specifically, the northward migration of the ITCZ and the eastward position of the Bermuda High during summer months leads to warmer and wetter conditions over subtropical North America, and vice versa. A quantitative approach to understanding hydrologic dynamics (i.e. atmospheric circulation patterns, relative humidity) associated with these …

Development Of An End-Effector Sensory Suite For A Rehabilitation Robot, Stephanie A. Stiber

USF Tampa Graduate Theses and Dissertations

This research presents an approach in assisting the control and operation of a rehabilitation robot manipulator to execute simple grasping tasks for persons with severe disabilities. It outlines the development of an end-effector sensory suite that includes the BarrettHand end-effector, laser range finder, and a low cost camera.

The approach taken in this research differs greatly from the currently available rehabilitation robot arms in that it requires minimal user instruction, it is easy to operate and more effective for persons severely disabled. A thorough study of the currently available systems; Manus, Raptor and Kares II arm, is also presented.

In …

Electrical Characterization Of Metal-To-Insulator Transition In Iron Silicide Thin Films On Silicon Substrates, Hasitha C. Weerasinghe

USF Tampa Graduate Theses and Dissertations

Iron Silicide (FeSi) films deposited on silicon substrates with the native SiO₂ layer have shown a Metal-to-Insulator Transition (MIT) of more than four order of magnitude change in resistance. Modification of the SiO2/Si interface due to Fe diffusion has been attributed to the formation of this effect. In this research a systematic experimental investigation has been carried out to study the effect of the growth parameters and substrate doping type in the transition. In addition, transport properties of continuous and discontinuous films have been investigated to understand the mechanism of this metal-to-insulator transition.

Four probe measurements of films deposited …

Assessment Of Occupational Heat Strain, Margaret Wan

USF Tampa Graduate Theses and Dissertations

Assessment of heat strain considers an individual’s tolerance and indicates the risk and physiological cost of working in hot environments. This study evaluated the discrimination ability of metrics of heat strain. The null hypotheses were that (1) the metrics individually could not discriminate between acceptable and unacceptable heat strain, (2) there were no significant differences among these metrics, and (3) there were no significant differences in the applicability of the metrics due to clothing or heat stress level.

The experimental design was a case crossover. Clothing and heat stress level were potential confounders. Two clothing ensembles were work clothes and …

Knowledge-Based Video Compression For Robots And Sensor Networks, Chris Williams Williams

USF Tampa Graduate Theses and Dissertations

Robot and sensor networks are needed for safety, security, and rescue applicationssuch as port security and reconnaissance during a disaster. These applications rely on realtimetransmission of images, which generally saturate the available wireless networkinfrastructure. Knowledge-based Compression is a strategy for reducing the video frametransmission rate between robots or sensors and remote operators. Because images mayneed to be archived as evidence and/or distributed to multiple applications with differentpost processing needs, lossy compression schemes, such as MPEG, H.26x, etc., are notacceptable. This work proposes a lossless video server system consisting of three classesof filters (redundancy, task, and priority) which use different levels …