Arts and Humanities Commons^™

Determination Of Ibuprofen Isotherm Using Supercritical Fluid Chromatography, Loi Ho

USF Tampa Graduate Theses and Dissertations

Chromatography is widely used to determine physiochemical properties data including adsorption isotherm. In the separation of enantiomers through sorptive processes, supercritical fluids allow efficient and green alternatives to liquid solvent based systems. The isotherm information is vital in the development of operating policies and design of preparative chromatographic or moving bed separation schemes. Determination of sorption isotherms from experimental chromatographic elution data is automated and compared with different chromatogram model. Procedures were developed and validated for separation of R- and S- ibuprofen with supercritical 〖CO〗_2 and ethanol mixture as the mobile phase over a chiral stationary phase. The isotherms for …

Actualizing Empowerment: Developing A Framework For Partnering With Families In System Level Service Planning And Delivery, Kathleen Ferreira

USF Tampa Graduate Theses and Dissertations

The engagement of families of children and adolescents with Serious Emotional Disturbance (SED) as full partners in individual treatment, organizational, and system level decision making has become an important focus for systems of care (SOCs) serving youth with emotional and behavioral challenges. SOCs typically include cross-agency partnerships with mental health, child welfare, juvenile justice, and education for the purpose of providing services and supports for youth with SED who have multi-agency needs. Implementation of a federal mandate requiring family driven care (FDC) within systems of care funded through the Children's Mental Health Initiative (CMHI) has revealed that most system of …

Asymmetric Passive Dynamic Walker Used To Examine Gait Rehabilitation Methods, John Sushko

USF Tampa Graduate Theses and Dissertations

Testing gait rehabilitation devices on humans can be a difficult task, due to the effects of the neurological controls of the human body. This thesis advances the use of a passive dynamic walker (PDW) tuned to have asymmetric gait patterns similar to those with physical impairments to test rehabilitation devices. A passive dynamic walker is a multipendulum system that has a stable gait pattern when walking down a slope without any energy inputs except the forces due to gravity. A PDW model is better suited for testing rehabilitation devices because it has been shown to resemble human gait and separates …

The Influence Of Daily Social Stimulation In Ameliorating Ptsd-Like Behavioral And Physiological Changes In Rats Exposed To Chronic Psychosocial Stress, Shyam Seetharaman

USF Tampa Graduate Theses and Dissertations

Individuals exposed to life-threatening trauma are at increased risk for developing post-traumatic stress disorder (PTSD). Not all people exposed to trauma, however, go on to develop PTSD. Some evidence suggests that individuals who receive social stimulation, such being involved in supportive social networks, are less likely to develop PTSD compared to those lacking social interactions. Although human research has been effective in demonstrating associations between higher levels of social stimulation and lower incidences of PTSD, there has been a lack of experimental evidence suggesting that social stimulation protects against the onset of the disorder after trauma. Here, we tested the …

The Model-Based Systematic Development Of Logis Online Graphing Instructional Simulator, Darrel R. Davis

USF Tampa Graduate Theses and Dissertations

This Developmental Research study described the development of an interactive online graphing instructional application and the impact of the Analysis Design Development Implementation Evaluation (ADDIE) model on the development process. An optimal learning environment was produced by combining Programmed Instruction and Adaptive Instruction principles with a graphing simulator that implemented guided contingent practice. The development process entailed the creation and validation of three instruments measuring knowledge, skills, and attitudes, which were components of the instruction.

The research questions were focused on the influence of the ADDIE model on the development process and the value of the LOGIS instructional application. The …

Bathymetric Alterations Due To Urbanization And Their Effects On Residual Salinity, Flow Field And Transport Time For Tampa Bay, Florida, Amanda J. Linville

USF Tampa Graduate Theses and Dissertations

Growth and development over the past one hundred years has resulted in the construction of causeways and navigational channels in Tampa Bay. Urbanization has lead to bathymetric alterations of the bay, and thus has effectively changed the residual salinity, flow fields, and transport time in Tampa Bay. In this study a numerical ocean model of Tampa Bay was first used to simulate the circulation for 2001-2003 using present day bathymetry. Then, an identical simulation was performed using the bathymetry generated from 1879 depth soundings. The residual (30-day time average) circulation fields and salinity, along with transport times was intercompared for …

Improved Techniques For Nonlinear Electrothermal Fet Modeling And Measurement Validation, Charles Passant Baylis Ii

USF Tampa Graduate Theses and Dissertations

Accurate transistor models are important in wireless and microwave circuit design. Large-signal field-effect transistor (FET) models are generally extracted from current-voltage (IV) characteristics, small-signal S-parameters, and large-signal measurements. This dissertation describes improved characterization and measurement validation techniques for FET models that correctly account for thermal and trapping effects.

Demonstration of a customized pulsed-bias, pulsed-RF S-parameter system constructed by the author using a traditional vector network analyzer is presented, along with the design of special bias tees to allow pulsing of the bias voltages. Pulsed IV and pulsed-bias S-parameter measurements can provide results that are electrodynamically accurate; that is, thermal and …

Structure And Dynamics Of Heterogeneous Molecular Systems, Alfred B. Roney

USF Tampa Graduate Theses and Dissertations

Although current classical force fields describe homogeneous single-componentsystems fairly well, they do not represent the response of an individual molecule's electronic structure to its local environment with enough detail to reliably predict atomic motions in interfacial regions such as a solvation structure or liquid surface.Since most chemical processes of non-trivial interest involve two or more dissimilar molecules interacting at a short distance, molecular models must accurately simulate the interactions between different molecular species as well as bulk behavior in order to provide useful information. Results from two simulation studies are presented to illustrate both the utility of current point-charge electrostatics …

Development Of A Gis Based Infrastructure Replacement Prioritization System; A Case Study, Brian D. Pickard

USF Tampa Graduate Theses and Dissertations

Maintenance, repair, and replacement of transmission mains and distribution system piping is expected to cost approximately $75 billion over the next two decades to ensure that public water systems are capable of providing the United States with safe drinking water. However, there is a significant gap between the funds available and the projected costs of infrastructure replacement or rehabilitation. Infrastructure Management Systems (IMS) have been developed to assist utilities and decision-makers in determining how to allocate resources for infrastructure. This project utilizes theTampa Water Department (TWD) as a case study to develop a tool for prioritizing infrastructure replacement.

TWD is …

Effects Of Trait Anxiety And Cognitive Appraisals On Emotional Reactions To Psychological And Physical Stressors, Qutayba Abdullatif

USF Tampa Graduate Theses and Dissertations

This study investigated the effects of individual differences in trait anxiety on cognitive appraisals and emotional reactions to stressful situations. Specifically, the effects of trait anxiety on the evaluation of psychological and physical threats to well-being were examined in relation to state-anxiety. To accomplish this goal, a proposed model consisting of elements from the Lazarus and Folkman Stress and Coping Model (1984) and Spielberger's State Trait distinctions is presented. To our knowledge, this is the first proposed model to attempt to combine trait anxiety, primary and secondary appraisals, and state anxiety and to utilize path analytic models in assessing empirical …

Linearity Optimization Of Power Transistors Utilizing Harmonic Terminations, Ravi Kumar Varanasi

USF Tampa Graduate Theses and Dissertations

This thesis focuses on the characterization and optimization of microwave power transistors using a commercial on-wafer harmonic load pull system. Specific attention is paid to the output tuning of the second harmonic impedance presented to the device. The ability to quantify the level of accuracy in a load pull system is explored by using various calibration validation methods, including a method called Delta-Gt. In this work experiments and simulation comparisons are described for three different device technologies, namely GaAs pHEMT, GaAs HJFET and InGaP HBT. Externally supplied non-linear models were used for the simulations and these were exercised and compared …

Technology And Teacher Training: The Systematic Design And Development Of A Framework For Integrating Technology Into Jamaica’S Teacher Training Programs, Carol N. Granston

USF Tampa Graduate Theses and Dissertations

Over the last five years, there has been an increased number of computers in schools and teachers' colleges in Jamaica. In addition, recently revised national policy documents have indicated the need to infuse technology into the curricula of all schools. Despite these investments in computers, however, there has been little corresponding development in training teachers to use computers and emerging technologies as teaching learning tools.

The purposes of the study were three-fold: (a) to describe the current state of technology integration in Jamaica's teacher training programs (b) assess the extent to which teachers' college faculty and pre-service teachers perceived themselves …

Improved 1/F Noise Measurements For Microwave Transistors, Clemente Toro Jr.

USF Tampa Graduate Theses and Dissertations

Minimizing electrical noise is an increasingly important topic. New systems and modulation techniques require a lower noise threshold. Therefore, the design of RF and microwave systems using low noise devices is a consideration that the circuit design engineer must take into account. Properly measuring noise for a given device is also vital for proper characterization and modeling of device noise. In the case of an oscillator, a vital part of a wireless receiver, the phase noise that it produces affects the overall noise of the system. Factors such as biasing, selectivity of the input and output networks, and selectivity of …

Operational Evaluation Of Right Turns Followed By U-Turns At Signalized Intersections As An Alternative To Direct Left Turns, Jingjing Fan

USF Tampa Graduate Theses and Dissertations

Direct left turn (DLT) movements have a lot safety and operation problems. They increase conflicts, delay and reduce capacity of the roadway. Increasing, many states and transportation agencies are considering using right-turns followed by u-turns as an alternative to direct left turns. Recently, Florida state are planning to close median openings in order to reduce the safety and operational problems caused by DLT. The left-turn egress movement would then to be made by turning right to the arterial road and then making a u-turn at an available downstream median opening or a signalized intersection. FDOT sponsored a project in 2001 …

Effects Of Faculty And Peer Mentoring On Perceived Stress And Social Support Of College Student Athletes, Valerie R. Pfister

USF Tampa Graduate Theses and Dissertations

Mentoring programs often focus on assisting students with the transition to college life and encouraging academic success. This study consisted of a quantitative examination of faculty and peer mentoring and freshmen student athletes' perceived transitional stress and social support. Surveys that provided a numerical value to perceived stress and social support supplied a basis for comparison. In addition, a qualitative element, consisting of personal interviews, was used to assess the quality of the mentoring relationships that developed.

Volunteer mentors were trained on mentoring strategies by the researcher. Sixty-one student-athlete volunteers from the sports of baseball, basketball, cheerleading, cross country, competitive …

A Mathematical Model For Colloidal Aggregation, Colleen S. O'Brien

USF Tampa Graduate Theses and Dissertations

The characterization of fine particles is an area of immense significance to many industrial endeavors. It has been estimated that 70% of all industrial processes deal with fine particles at some point in the process. A natural phenomenon occurring in these processes is colloidal aggregation. This study examines aggregation in colloidal systems in order to characterize, examine, and control this occurrence in industrial processes. The study of particle aggregation has been broken into many different areas, such as collision mechanisms, interaction energy etc, but a complete model that integrates these different aspects has never been fully realized. A new model …

Design And Characterization Of Multi-Layer Coplanar Waveguid Baluns And Inductors, Khaled Obeidat

USF Tampa Graduate Theses and Dissertations

This work examined the design and characterization of multilayer coplanar waveguide baluns and inductors. This work derives a design procedure that helps RF engineers design cost effective multilayer coplanar waveguide (CPW) spiral balun that works in the frequency range 1-8 GHz. The accuracy of the developed procedure has been proven by designing two balun circuits of different dimensions and simulating them using available commercial software, Momentum (MoM) and Empire (FDTD). The simulation results have shown good balun performance over the desired frequency range. Furthermore some of the designed balun circuits have been fabricated and measured and the results agree with …