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Electronic Theses and Dissertations

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Leadership Orientations Of Senior Administrators At American Metropolitan Universities, Diane Trees Jan 2006

Leadership Orientations Of Senior Administrators At American Metropolitan Universities, Diane Trees

Electronic Theses and Dissertations

Universities in the United States continue to evolve far beyond traditional concepts. While problems of an academic, economic, governmental, and educational nature beset any university, the metropolitan institution must grapple with these issues not as an individual entity but as a partner in a group of many players. Educational leadership for the American metropolitan university necessitates distinct and unique skills. This study sought to explore leadership behaviors of senior administrators at American metropolitan universities as conceptualized by Bolman and Deal's Four-Frame Model of Leadership (1991). Using Bolman and Deal's (1990) Leadership Orientations Survey (Self) instrument with an additional Respondent Information …


A Fluid Structure Interaction Model Of Intracoronary Atherosclerotic Plaque Rupture, Eric Teuma-Melago Jan 2006

A Fluid Structure Interaction Model Of Intracoronary Atherosclerotic Plaque Rupture, Eric Teuma-Melago

Electronic Theses and Dissertations

Plaque rupture with superimposed thrombosis is the primary cause of acute coronary syndromes of unstable angina, myocardial infarction and sudden death. Although intensive studies in the past decade have shed light on the mechanism that causes unstable atheroma, none has directly addressed the clinical observation that most myocardial infarction (MI) patients have moderate stenoses (less than 50%). Considering the important role the arterial wall compliance and pulsitile blood flow play in atheroma rupture, fluid-structure interaction (FSI) phenomenon has been of interest in recent studies. In this thesis, the impact is investigated numerically of coupled blood flow and structural dynamics on …


The Relationship Between Self-Reported Chronic Stress And Divided Attention Performance, Diane Petrac Jan 2006

The Relationship Between Self-Reported Chronic Stress And Divided Attention Performance, Diane Petrac

Electronic Theses and Dissertations

While previous research has extensively examined the effect of acute stress on cognitive performance, relatively little research has explored the relationship between chronic stress and cognitive performance. The current study aimed to control for current state anxiety to better isolate more chronic stress, when examining the relationship with performance on divided attention tasks. Fifty-four university undergraduates, who self-reported a wide range of perceived chronic stress (10-item Perceived Stress Scale), completed the Trail-Making Test and a dual (auditory and visual) Continuous Performance Test (CPT). Hierarchical regressions were performed to explore cognitive predictors of chronic perceived stress. After covarying for state anxiety …


New Developments On High-Resolution Luminescence Spectroscopy And Their Application To The Direct Analysis Of Organic Pollutants, Shenjiang Yu Jan 2006

New Developments On High-Resolution Luminescence Spectroscopy And Their Application To The Direct Analysis Of Organic Pollutants, Shenjiang Yu

Electronic Theses and Dissertations

Polycyclic aromatic compounds (PACs), which comprise a complex class of condensed multi-ring benzenoid compounds, are important environmental pollutants originating from a wide variety of natural and anthropogenic sources. PACs are generally formed during incomplete combustion of pyrolisis of organic matter containing carbon and hydrogen. Because combustion of organic materials is involved in countless natural processes or human activities, PACs are omnipresent and abundant pollutants in air, soil, and water. Chemical analysis of PACs is of great environmental and toxicological importance. Many of them are highly suspect as etiological agents in human cancer. Because PACs carcinogenic properties strongly depend on molecular …


Image-Based Material Editing, Erum Khan Jan 2006

Image-Based Material Editing, Erum Khan

Electronic Theses and Dissertations

Photo editing software allows digital images to be blurred, warped or re-colored at the touch of a button. However, it is not currently possible to change the material appearance of an object except by painstakingly painting over the appropriate pixels. Here we present a set of methods for automatically replacing one material with another, completely different material, starting with only a single high dynamic range image, and an alpha matte specifying the object. Our approach exploits the fact that human vision is surprisingly tolerant of certain (sometimes enormous) physical inaccuracies. Thus, it may be possible to produce a visually compelling …


Decoherence In Quantum Dot Charge Qubits: The Role Of Electromagnetic Fluctuations, James Mccracken Jan 2006

Decoherence In Quantum Dot Charge Qubits: The Role Of Electromagnetic Fluctuations, James Mccracken

Electronic Theses and Dissertations

Lateral semiconductor quantum dot structures have been proposed as an effective quantum bit (qubit) for quantum computation. A single excess electron with the freedom to move between two capacitively coupled quantum dots creates a `pseudo'-spin system with the same qubit behavior as the more natural two level system of a single electron spin. The excess electron in the double dot system is restricted to one of the two dots, thereby creating two separate and distinct states (usually referred to as |L> and |R>). The benefit of these charge qubits lie in the relative ease with which they can be …


An Evaluation Of The Effects Of A Leisure Education Curriculum On Deliquents' Motivation, Knowledge, And Behavior Changes Related To Boredom, Paul Finn Jr. Jan 2006

An Evaluation Of The Effects Of A Leisure Education Curriculum On Deliquents' Motivation, Knowledge, And Behavior Changes Related To Boredom, Paul Finn Jr.

Electronic Theses and Dissertations

Adolescents today have more unsupervised and unstructured free time than ever before. Poor decisions by youth during periods of free time may lead to substance abuse, teen pregnancy and juvenile delinquency. The highest frequency of juvenile crime, a major social problem, occurs during the 2-4 hours following the end of the school day. Research has demonstrated the benefits of engaging adolecents in prosocial leisure activity. However, no research has studied the issues of free time and leisure education with a delinquent population. This paper documents the impact of a leisure education curriculum on a population of delinquent youth in a …


Student Disability Services Within The 28 Florida Community Colleges, Alice Godbey Jan 2006

Student Disability Services Within The 28 Florida Community Colleges, Alice Godbey

Electronic Theses and Dissertations

The purpose of this research study was to investigate perceptions and activities of disability support program administrators in Florida community colleges regarding program administration and evaluation. The study further sought to document if any relationships existed between selected organizational and staffing characteristics and the program's ability to follow an established set of standards for program administration and evaluation. A total of 25 disability support administrators (89.3% response rate) completed a phone survey designed for this study. The study revealed that there were many inconsistencies among the higher education disability support programs in regard to programming, staffing and data collecting activities. …


Experiments In Pool Boiling Heat Transfer And Nucleationdynamics Of High Pressure Refrigerants, Daniel Joo Jan 2006

Experiments In Pool Boiling Heat Transfer And Nucleationdynamics Of High Pressure Refrigerants, Daniel Joo

Electronic Theses and Dissertations

A high pressure pool boiling experiment of pressurized R134a is designed and built, utilizing thermochromatic liquid crystal techniques. Liquid crystals thermo-chromatography uses encapsulated liquid crystals that are sensitive to temperature. When exposed to hot temperatures the crystal reflect a blue/violet color, and when exposed to cooler temperatures it reflects a red/orange color. The color value or hue is proportional to its temperature. Using this technique this experiment is capable of studying the physics and thermodynamics of refrigerants under nucleate pool boiling. The main objective of this experiment was the design of the experimental setup. Various designs were tested and validated, …


Reduction Of Vortex-Driven Oscillations In A Solid Rocket Motor Cold Flow Simulation Through Active Control, Jami Ward Jan 2006

Reduction Of Vortex-Driven Oscillations In A Solid Rocket Motor Cold Flow Simulation Through Active Control, Jami Ward

Electronic Theses and Dissertations

Control of vortex-driven instabilities was demonstrated via a scaled-down, cold-flow simulation that modeled closed-end acoustics. When vortex shedding frequencies couple with the natural acoustic modes of a choked chamber, potentially damaging low-frequency instabilities may arise. Although passive solutions can be effective, an active control solution is preferable. An experiment was performed to demonstrate an active control scheme for the reduction of vortex-driven oscillations. A non-reacting experiment using a primary flow of air, where both the duct exit and inlet are choked, simulated the closed-end acoustics. Two plates, separated by 1.27 cm, produced the vortex shedding phenomenon at the chamber's first …


Trends In The Selection, Evaluation, And Compensation Of University Presidents In The Florida State University System, Nancy L. Marshall Jan 2006

Trends In The Selection, Evaluation, And Compensation Of University Presidents In The Florida State University System, Nancy L. Marshall

Electronic Theses and Dissertations

Recent literature suggested that while the discussion of presidential selection, evaluation, and compensation was common to both private and public institutions, special attention was paid to public university presidents. They and their presidencies were subject to intense public debate and scrutiny. Florida's public university presidents have contended with the same issues as their counterparts in other states. However, the 2001 changes in the state's higher education governance created distinct challenges and opportunities for the 11 presidents in the Florida State University System. The purpose of this study was to analyze the trends in the selection, evaluation, and compensation of the …


Electrical Properties Of Reactive Magnetron Sputtered Vanadium Oxide Thin Films, Vu Huynh Lam Jan 2006

Electrical Properties Of Reactive Magnetron Sputtered Vanadium Oxide Thin Films, Vu Huynh Lam

Electronic Theses and Dissertations

It is well known that vanadium oxide can take many different forms. However for this study, only the amorphous phase was investigated. Amorphous vanadium oxide (VOx) thin films were deposited on thermally grown silicon dioxide by DC magnetron sputtering using a vanadium metal target in an argon / oxygen atmosphere. The driving force of this study was to investigate the temperature coefficient of resistance (TCR) and low resistivity in the amorphous films. Sheet resistance is very sensitive to small changes in temperature, making amorphous VOx very attractive to thermal sensor applications such as infrared detectors. To form the vanadium oxide, …


Sarp Net: A Secure, Anonymous, Reputation-Based, Peer-To-Peer Network, Sean Mondesire Jan 2006

Sarp Net: A Secure, Anonymous, Reputation-Based, Peer-To-Peer Network, Sean Mondesire

Electronic Theses and Dissertations

Since the advent of Napster, the idea of peer-to-peer (P2P) architectures being applied to file-sharing applications has become popular, spawning other P2P networks like Gnutella, Morpheus, Kazaa, and BitTorrent. This growth in P2P development has nearly eradicated the idea of the traditional client-server structure in the file-sharing model, now placing emphasizes on faster query processing, deeper levels of decentralism, and methods to protect against copyright law violation. SARP Net is a secure, anonymous, decentralized, P2P overlay network that is designed to protect the activity of its users in its own file-sharing community. It is secure in the fact that public-key …


A Comparative Study Of Ant Colony Optimization, Matthew Becker Jan 2006

A Comparative Study Of Ant Colony Optimization, Matthew Becker

Electronic Theses and Dissertations

Ant Colony Optimization (ACO) belongs to a class of biologically-motivated approaches to computing that includes such metaheuristics as artificial neural networks, evolutionary algorithms, and artificial immune systems, among others. Emulating to varying degrees the particular biological phenomena from which their inspiration is drawn, these alternative computational systems have succeeded in finding solutions to complex problems that had heretofore eluded more traditional techniques. Often, the resulting algorithm bears little resemblance to its biological progenitor, evolving instead into a mathematical abstraction of a singularly useful quality of the phenomenon. In such cases, these abstract computational models may be termed biological metaphors. Mindful …


Pharmacological Characterization Of Brain Angiotensin Ii Receptor Function And Ligand Binding, Surinder Kaur Jan 2006

Pharmacological Characterization Of Brain Angiotensin Ii Receptor Function And Ligand Binding, Surinder Kaur

Electronic Theses and Dissertations

No abstract provided.


Disillusionment, Kimberly Lockhart Noll Jan 2006

Disillusionment, Kimberly Lockhart Noll

Electronic Theses and Dissertations

No abstract provided.


Use Of Portable Falling Weight Deflectometer For Estimating Resilient Modulus Of Subgrade, Biplab Bhushan Bhattacharya Jan 2006

Use Of Portable Falling Weight Deflectometer For Estimating Resilient Modulus Of Subgrade, Biplab Bhushan Bhattacharya

Electronic Theses and Dissertations

No abstract provided.


Design And Performance Evaluation Of An Integrated Miniature Single Stage Centrifugal Compressor And Permanent Magnet Synchronous Motor, Dipjyoti Acharya Jan 2006

Design And Performance Evaluation Of An Integrated Miniature Single Stage Centrifugal Compressor And Permanent Magnet Synchronous Motor, Dipjyoti Acharya

Electronic Theses and Dissertations

An attempt has been made in this present work to design, fabricate and performance evaluate an integrated single stage centrifugal compressor and permanent magnet synchronous motor which is a key component of the reverse brayton cycle cryocooler. An off the shelf compressor – the driven and electric motor – the driver was not available commercially to suffice the requirements of the reverse brayton cryocooler. The integrated compressor-motor system was designed and tested with air as the working fluid at mass flow rate of 7.3 grams per sec, with a compression ratio of 1.58 and driven by a 2 KW permanent …


Effectiveness And Kinetics Of Ferrate As A Disinfectant For Ballast Water, Andrea L. Jessen Jan 2006

Effectiveness And Kinetics Of Ferrate As A Disinfectant For Ballast Water, Andrea L. Jessen

Electronic Theses and Dissertations

The introduction of aquatic nuisance species (ANS) and bacterial pathogens from discharge of ballast water by sea-faring vessels is an ongoing problem that threatens ecosystems and human health. This study investigates the disinfecting capability of ferrate in a marine environment on several organisms listed in international standards for ballast water management. Organisms were grown in a saline solution and were treated with dosages of ferrate ranging from 0.25-5.0 mg/l. A ferrate dose of 5 mg/l resulted in almost complete kill for all organisms tested. Smaller dosages have also been very effective, particularly if all organic material from the nutrient broth …


Commissioning Of A Dynamic Mechanical Analyzerfor The Characterization Of Low Temperature Nitife Shape Memory Alloys, Maruthi Diwakar Nandiraju Jan 2006

Commissioning Of A Dynamic Mechanical Analyzerfor The Characterization Of Low Temperature Nitife Shape Memory Alloys, Maruthi Diwakar Nandiraju

Electronic Theses and Dissertations

NiTiFe shape memory alloys can undergo transformations between cubic, trigonal and monoclinic phases at low temperatures. The low hysteresis associated with the trigonal R-phase transformation make them candidates for actuator applications at low temperatures. However, the literature available on these alloys is limited and there is a need to establish processing structure-property correlations. This study was undertaken with the objective of determining and understanding such correlations in a Ni46.8Ti50Fe3.2 alloy. First, a dynamic mechanical analyzer (DMA) was successfully commissioned to facilitate mechanical testing between -150 and 600ºC. The experiments performed over selected ranges of stress and temperature probed a range …


Developing Emergency Preparedness Plans For Orlando International Airport (Mco) Using Microscopic Simulator Watsim, Daniel Dawson Jan 2006

Developing Emergency Preparedness Plans For Orlando International Airport (Mco) Using Microscopic Simulator Watsim, Daniel Dawson

Electronic Theses and Dissertations

Emergency preparedness typically involves the preparation of detailed plans that can be implemented in response to a variety of possible emergencies or disruptions to the transportation system. One shortcoming of past response plans was that they were based on only rudimentary traffic analysis or in many cases none at all. With the advances in traffic simulation during the last decade, it is now possible to model many traffic problems, such as emergency management, signal control and testing of Intelligent Transportation System technologies. These problems are difficult to solve using the traditional tools, which are based on analytical methods. Therefore, emergency …


Analysis, Modeling, And Simulation Of The Tides In The Loxahatchee River Estuary (Southeastern Florida)., Peter Bacopoulos Jan 2006

Analysis, Modeling, And Simulation Of The Tides In The Loxahatchee River Estuary (Southeastern Florida)., Peter Bacopoulos

Electronic Theses and Dissertations

Recent cooperative efforts between the University of Central Florida, the Florida Department of Environmental Protection, and the South Florida Water Management District explore the development of a two-dimensional, depth-integrated tidal model for the Loxahatchee River estuary (Southeastern Florida). Employing a large-domain approach (i.e., the Western North Atlantic Tidal model domain), two-dimensional tidal flows within the Loxahatchee River estuary are reproduced to provide: 1) recommendations for the domain extent of an integrated, surface/groundwater, three-dimensional model; 2) nearshore, harmonically decomposed, tidal elevation boundary conditions. Tidal simulations are performed using a two-dimensional, depth-integrated, finite element-based code for coastal and ocean circulation, ADCIRC-2DDI. Multiple …


Dsp Implementation Of Dc Voltage Regulation Using Adaptive Control For 200 Kw 62000 Rpm Induction Generator, Othman Elkhomri Jan 2006

Dsp Implementation Of Dc Voltage Regulation Using Adaptive Control For 200 Kw 62000 Rpm Induction Generator, Othman Elkhomri

Electronic Theses and Dissertations

The thesis discusses the development of closed loop system to control the DC voltage for 200 kW induction generator rated at a speed of 62000 RPM under different load conditions. The voltage regulation has been implemented using PI controller. A gain scheduling control algorithm has been developed to select the appropriate controller gains with respect to the generator load. Further, a relationship between the generator loads and the controller gains has been established. This relationship has been modeled using adaptive control technique to vary the gains automatically at any load condition. The adaptive control technique has been successfully generalized for …


Genetically Engineered Adaptive Resonance Theory (Art) Neural Network Architectures, Ahmad Al-Daraiseh Jan 2006

Genetically Engineered Adaptive Resonance Theory (Art) Neural Network Architectures, Ahmad Al-Daraiseh

Electronic Theses and Dissertations

Fuzzy ARTMAP (FAM) is currently considered to be one of the premier neural network architectures in solving classification problems. One of the limitations of Fuzzy ARTMAP that has been extensively reported in the literature is the category proliferation problem. That is Fuzzy ARTMAP has the tendency of increasing its network size, as it is confronted with more and more data, especially if the data is of noisy and/or overlapping nature. To remedy this problem a number of researchers have designed modifications to the training phase of Fuzzy ARTMAP that had the beneficial effect of reducing this phenomenon. In this thesis …


Evaluation Of Space Shuttle Tile Subnominal Bonds, Cooper Snapp Jan 2006

Evaluation Of Space Shuttle Tile Subnominal Bonds, Cooper Snapp

Electronic Theses and Dissertations

This study researched the history of Space Shuttle Reusable Surface Insulation which was designed and developed for use on the United States Orbiter fleet to protect from the high heating experienced during reentry through Earth's atmosphere. Specifically the tile system which is attached to the structure by the means of an RTV adhesive has experienced situations where the bonds are identified as subnominal. The history of these subnominal conditions is presented along with a recent identification of a subnominal bond between the Strain Isolation Pad and the tile substrate itself. Tests were run to identify the cause of these subnominal …


A Methodology For Instrumented Indentation Studies Of Deformation In Bulk Metallic Glasses, Subhaashree Sridharan Jan 2006

A Methodology For Instrumented Indentation Studies Of Deformation In Bulk Metallic Glasses, Subhaashree Sridharan

Electronic Theses and Dissertations

Bulk Metallic Glasses (BMGs), also known as amorphous metals, are of considerable scientific and commercial interest due to their random or chaotic structure. Given their potential use as engineering materials, there is a concomitant need to establish their mechanical properties. However, BMGs are not conveniently available in sufficient volumes (especially experimental and combinatorial compositions), making property determination via conventional tensile or compression testing problematic. Instrumented indentation is ideally suited for this purpose because the testing requires only small sampling volumes and can probe multiaxial deformation characteristics at various length scales. In this technique, conducted generally on a sub-micron regime, the …


The Effect Of Hot Carrier Stress On Low Noise Amplifier Radio Frequency Performance Under Weak And Strong Inversion, Lin Shen Jan 2006

The Effect Of Hot Carrier Stress On Low Noise Amplifier Radio Frequency Performance Under Weak And Strong Inversion, Lin Shen

Electronic Theses and Dissertations

This thesis work is mainly focused on studying RF performance degradation of a low noise amplifier (LNA) circuit due to hot carrier effect (HCE) in both the weak and strong inversion regions. Since the figures of merit for the RF circuit characterization are gain, noise figure, input, and output matching, the LNA RF performance drift is evaluated in a Cadence SpectreRF simulator subject to these features. This thesis presents hot carrier induced degradation results of an LNA to show that the HCE phenomenon is one of the serious reliability issues in the aggressively scaled RF CMOS design, especially for long-term …


Modeling And Optimization Of Body Diode Reverse Recovery Characteristics Of Ldmos Transistors, Wesley Deschaine Jan 2006

Modeling And Optimization Of Body Diode Reverse Recovery Characteristics Of Ldmos Transistors, Wesley Deschaine

Electronic Theses and Dissertations

As switching speeds for DC-DC converter applications keep becoming faster and faster and voltage requirements become smaller and smaller, the need for new device structures becomes more prevalent. Designers of these new structures will need to make sure they take into consideration the different power losses associated with the different structures and make modifications to reduce or if possible eliminate them. A new 30V LDMOS device has been created and is being implemented into a synchronous buck converter for future DC-DC conversions. This new lateral device has a Figure of Merit of 80mÙ*nC, representing a 50% reduction from the conventional …


Lattice Vibration Study Of Silica Nanoparticle In Suspension, Parveen Sachdeva Jan 2006

Lattice Vibration Study Of Silica Nanoparticle In Suspension, Parveen Sachdeva

Electronic Theses and Dissertations

In recent years considerable research has been done in the area of "nanofluids". Nanofluids are colloidal suspensions of nanometer size metallic or oxide particles in a base fluid such as water, ethylene glycol. Nanofluids show enhanced heat transfer characteristics compared to the base fluid. The thermal transport properties of nanofluids depend on various parameters e.g. interfacial resistance, Brownian motion of particles, liquid layering at the solid-liquid interface and clustering of nanoparticles. In this work atomic scale simulation has been used to study possible mechanisms affecting the heat transfer characteristics of nanofluids. Molecular dynamics simulation for a single silica nanoparticle surrounded …


Oscillatory Flow As A Means Of Enhanced Species Separation: A Three Dimensional Time-Accurate Cfd Analysis, Jennifer Crain Jan 2006

Oscillatory Flow As A Means Of Enhanced Species Separation: A Three Dimensional Time-Accurate Cfd Analysis, Jennifer Crain

Electronic Theses and Dissertations

A fluid that contains species in the presence of a concentration gradient generates unusual phenomena when it is forced into pulsatile motion. For example, each species in the fluid has an enhanced mass transport due to pure molecular diffusion. This enhancement takes place even if there is no net total flow over a cycle of the pulsatile motion. When more than one species in dilute amounts is present in an otherwise pure fluid, called a carrier, each species is transported at a different rate thereby causing a partial separation of the species. This idea traces back to hyperventilation studies done …