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Electronic Theses and Dissertations

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Instrumented Nanoindentation Studies Of Deformation In Shape Memory Alloys, Sudhir Rajagopalan Jan 2005

Instrumented Nanoindentation Studies Of Deformation In Shape Memory Alloys, Sudhir Rajagopalan

Electronic Theses and Dissertations

Near equi-atomic nickel titanium (NiTi) shape memory alloys (SMAs) are a class of materials characterized by their unique deformation behavior. In these alloys, deformation mechanisms such as mechanical twinning and stress induced phase transformation between a high symmetry phase (austenite) and a low symmetry phase (martensite) additionally occur and influence mechanical behavior and thus their functionality. Consequently, applications of SMAs usually call for precise phase transformation temperatures, which depend on the thermomechanical history and the composition of the alloy. Instrumented indentation, inherently a mechanical characterization technique for small sampling volumes, offers a cost effective means of empirically testing SMAs in …

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Evaluation Of Toxic Cyanobacteria In Central Florida Stormwater Ponds, Robert Miller Jan 2005

Evaluation Of Toxic Cyanobacteria In Central Florida Stormwater Ponds, Robert Miller

Electronic Theses and Dissertations

Algal blooms are a common occurrence in water bodies of all shapes and sizes throughout the United States and countries around the world. The State of Florida is no exception to this phenomenon. Cyanobacteria, or blue-green algae, have proven to be of special concern due to its proliferation and potential to produce toxins that are harmful to humans, livestock and wildlife. A casual drive along the roads and in the neighborhoods of central Florida will confirm algal conditions in many areas. The potential for exposure to harmful and possibly fatal toxins associated with these algal blooms are becoming more evident …

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Finite Element Evaluation Of The Effects Of Lateral Anchorage Strips On The Behavior Of Cfrp-Strengthened Rc Beams, Jose Javier Perez Jan 2005

Finite Element Evaluation Of The Effects Of Lateral Anchorage Strips On The Behavior Of Cfrp-Strengthened Rc Beams, Jose Javier Perez

Electronic Theses and Dissertations

In this thesis, a fully nonlinear finite element study of the flexural behavior of doubly reinforced concrete beams strengthened using different Carbon Fiber Reinforced Polymer (CFRP) composite strengthening configurations has been carried out. Prior to the study, a total of six beams were constructed, pre-cracked, strengthened and tested to failure under a four-point loading condition (Zhao and O'Riordan-Adjah, 2004). Then, for the purpose of this thesis work, detailed three dimensional finite element models were created not only to correlate the results obtained from the experiments, but also to predict the load capacity, failure modes and crack pattern of reinforced concrete …

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Planning And Scheduling For Large-Scaledistributed Systems, Han Yu Jan 2005

Planning And Scheduling For Large-Scaledistributed Systems, Han Yu

Electronic Theses and Dissertations

Many applications require computing resources well beyond those available on any single system. Simulations of atomic and subatomic systems with application to material science, computations related to study of natural sciences, and computer-aided design are examples of applications that can benefit from the resource-rich environment provided by a large collection of autonomous systems interconnected by high-speed networks. To transform such a collection of systems into a user's virtual machine, we have to develop new algorithms for coordination, planning, scheduling, resource discovery, and other functions that can be automated. Then we can develop societal services based upon these algorithms, which hide …

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Studies Of Liquid Crystal Response Time, Haiying Wang Jan 2005

Studies Of Liquid Crystal Response Time, Haiying Wang

Electronic Theses and Dissertations

In this dissertation, the response time issue of the liquid crystal (LC) devices is investigated in meeting the challenges for display and photonic applications. The correlation between the LC director response time and the optical response time is derived theoretically and confirmed experimentally. A major contribution of this thesis is that, based on the small angle approximation, we derive rigorous analytical solutions for correlating the LC director response time to its consequent optical response times (both rise and decay) of a vertical-aligned nematic LC cell. This work successfully fills the gap in the literature of LCD switching dynamics. An important …

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Graph-Theoretic Approach To Modeling Propagation And Control Of Network Worms, Zoran Nikoloski Jan 2005

Graph-Theoretic Approach To Modeling Propagation And Control Of Network Worms, Zoran Nikoloski

Electronic Theses and Dissertations

In today's network-dependent society, cyber attacks with network worms have become the predominant threat to confidentiality, integrity, and availability of network computing resources. Despite ongoing research efforts, there is still no comprehensive network-security solution aimed at controling large-scale worm propagation. The aim of this work is fivefold: (1) Developing an accurate combinatorial model of worm propagation that can facilitate the analysis of worm control strategies, (2) Building an accurate epidemiological model for the propagation of a worm employing local strategies, (3) Devising distributed architecture and algorithms for detection of worm scanning activities, (4) Designing effective control strategies against the worm, …

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The Effect Of Tidal Inlets On Open Coast Storm Surge Hydrographs: A Case Study Of Hurricane Ivan (2004), Michael Salisbury Jan 2005

The Effect Of Tidal Inlets On Open Coast Storm Surge Hydrographs: A Case Study Of Hurricane Ivan (2004), Michael Salisbury

Electronic Theses and Dissertations

Florida's Department of Transportation requires design storm tide hydrographs for coastal waters surrounding tidal inlets along the coast of Florida. These hydrographs are used as open ocean boundary conditions for local bridge scour models. At present, very little information is available on the effect that tidal inlets have on these open coast storm tide hydrographs. Furthermore, current modeling practice enforces a single design hydrograph along the open coast boundary for bridge scour models. This thesis expands on these concepts and provides a more fundamental understanding on both of these modeling areas. A numerical parameter study is undertaken to elucidate the …

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Super High-Speed Miniaturized Permanent Magnet Synchronous Motor, Liping Zheng Jan 2005

Super High-Speed Miniaturized Permanent Magnet Synchronous Motor, Liping Zheng

Electronic Theses and Dissertations

This dissertation is concerned with the design of permanent magnet synchronous motors (PMSM) to operate at super-high speed with high efficiency. The designed and fabricated PMSM was successfully tested to run upto 210,000 rpm The designed PMSM has 2000 W shaft output power at 200,000 rpm and at the cryogenic temperature of 77 K. The test results showed the motor to have an efficiency reaching above 92%. This achieved efficiency indicated a significant improvement compared to commercial motors with similar ratings. This dissertation first discusses the basic concept of electrical machines. After that, the modeling of PMSM for dynamic simulation …

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Adapting The Modified Cam Clay Constitutive Model To The Computational Analysis Of Dense Granular Soils, Jose Arvelo Jan 2005

Adapting The Modified Cam Clay Constitutive Model To The Computational Analysis Of Dense Granular Soils, Jose Arvelo

Electronic Theses and Dissertations

The computational constitutive Modified Cam Clay Model (MCCM) was developed at Cambridge to study the behavior of clays and has been proven to be effective. In this study, this model is extended to the case of dense sands to analyze the accuracy of the stress-strain behavior. This analysis is based on triaxial test data applied to remolded and compacted sand samples under drained conditions. The laboratory triaxial tests were performed by the Florida Department of Transportation to research the permeability effect in sandy soils compacted up to 95% of maximum unit weight at the optimum moisture content. Each soil sample …

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Contributions To Automatic Particle Identification In Electron Micrographs: Algorithms, Implementation, And Applications, Vivek Singh Jan 2005

Contributions To Automatic Particle Identification In Electron Micrographs: Algorithms, Implementation, And Applications, Vivek Singh

Electronic Theses and Dissertations

Three dimensional reconstruction of large macromolecules like viruses at resolutions below 8 Ã… - 10 Ã… requires a large set of projection images and the particle identification step becomes a bottleneck. Several automatic and semi-automatic particle detection algorithms have been developed along the years. We present a general technique designed to automatically identify the projection images of particles. The method utilizes Markov random field modelling of the projected images and involves a preprocessing of electron micrographs followed by image segmentation and post processing for boxing of the particle projections. Due to the typically extensive computational requirements for extracting hundreds of …

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Multizoom Activity Recognition Using Machine Learning, Raymond Smith Jan 2005

Multizoom Activity Recognition Using Machine Learning, Raymond Smith

Electronic Theses and Dissertations

In this thesis we present a system for detection of events in video. First a multiview approach to automatically detect and track heads and hands in a scene is described. Then, by making use of epipolar, spatial, trajectory, and appearance constraints, objects are labeled consistently across cameras (zooms). Finally, we demonstrate a new machine learning paradigm, TemporalBoost, that can recognize events in video. One aspect of any machine learning algorithm is in the feature set used. The approach taken here is to build a large set of activity features, though TemporalBoost itself is able to work with any feature set …

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Vibration Analysis Of Carbon Nanotube Using Continuum Model And Finite Element Model, Hari Subramaniam Jan 2005

Vibration Analysis Of Carbon Nanotube Using Continuum Model And Finite Element Model, Hari Subramaniam

Electronic Theses and Dissertations

The main objective of the thesis is to propose the methods of determining vibration behavior of carbon nanotubes (CNTs) using continuum models and finite element models. Secondary objective is to find the effect of van der Waals force on vibration of multiwalled carbon nanotubes . The study of vibration behavior of CNTs is important because of their potential engineering applications such as nano-mechanical resonators and tips of scanning probe instruments where they are subjected to mechanical vibrations. Continuum modeling is based on an elastic beam model. The interlayer van der Waals interactions are represented by Lennard-Jones potential. In finite element …

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Rr Interval Estimation From An Ecg Using A Linear Discrete Kalman Filter, Arun Janapala Jan 2005

Rr Interval Estimation From An Ecg Using A Linear Discrete Kalman Filter, Arun Janapala

Electronic Theses and Dissertations

An electrocardiogram (ECG) is used to monitor the activity of the heart. The human heart beats seventy times on an average per minute. The rate at which a human heart beats can exhibit a periodic variation. This is known as heart rate variability (HRV). Heart rate variability is an important measurement that can predict the survival after a heart attack. Studies have shown that reduced HRV predicts sudden death in patients with Myocardial Infarction (MI). The time interval between each beat is called an RR interval, where the heart rate is given by the reciprocal of the RR interval expressed …

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Speedes: A Case Study Of Space Operations, Amith Paruchuri Jan 2005

Speedes: A Case Study Of Space Operations, Amith Paruchuri

Electronic Theses and Dissertations

This thesis describes the application of parallel simulation techniques to represent the structured functional parallelism present within the Space Shuttle Operations Flow using the Synchronous Parallel Environment for Emulation and Discrete-Event Simulation (SPEEDES), an object-oriented multi-computing architecture. SPEEDES is a unified parallel simulation environment, which allocates events over multiple processors to get simulation speed up. Its optimistic processing capability minimizes simulation lag time behind wall clock time, or multiples of real-time. SPEEDES accommodates an increase in process complexity with additional parallel computing nodes to allow sharing of processing loads. This thesis focuses on the process of translating a model of …

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Oceanic Rain Identification Using Multifractal Analysis Of Quikscat Sigma-0, Vasud Ganesh Torsekar Jan 2005

Oceanic Rain Identification Using Multifractal Analysis Of Quikscat Sigma-0, Vasud Ganesh Torsekar

Electronic Theses and Dissertations

The presence of rain over oceans interferes with the measurement of sea surface wind speed and direction from the Sea Winds scatterometer and as a result wind measurements contain biases in rain regions. In past research at the Central Florida Remote Sensing Lab, it has been observed that rain has multi-fractal behavior. In this report we present an algorithm to detect the presence of rain so that rain regions are flagged. The forward and aft views of the horizontal polarization σ0 are used for the extraction of textural information with the help of multi-fractals. A single negated multi-fractal exponent is …

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Effects Of Transport Properties And Flame Unsteadiness On Nitrogen Oxides Emissions From Laminar Hydrogen Jet Diffusion Flames, Doyoub Park Jan 2005

Effects Of Transport Properties And Flame Unsteadiness On Nitrogen Oxides Emissions From Laminar Hydrogen Jet Diffusion Flames, Doyoub Park

Electronic Theses and Dissertations

Experimental studies on the coupled effects of transport properties and unsteady fluid dynamics have been conducted on laminar, acoustically forced, hydrogen jet diffusion flames diluted by argon and helium. The primary purpose of this research is to determine how the fuel Lewis number and the flow unsteadiness play a combined role in maximum flame temperature and affect NOx emission from jet diffusion flame. The fuel Lewis number is varied by increasing/decreasing the mole fraction of diluents in the fuel stream. Therefore, maximum flame temperatures and then NOx emission levels were expected to differ for Ar- and He-diluted flames. In an …

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Structural Condition Assessment Of Prestressed Concrete Transit Guideways, Robert Zachary Shmerling Jan 2005

Structural Condition Assessment Of Prestressed Concrete Transit Guideways, Robert Zachary Shmerling

Electronic Theses and Dissertations

Objective condition assessment is essential to make better decisions for safety and serviceability of existing civil infrastructure systems. This study explores the condition of an existing transit guideway system that has been in service for thirty-five years. The structural system is composed of six-span continuous prestressed concrete bridge segments. The overall transit system incorporates a number of continuous bridges which share common design details, geometries, and loading conditions. The original analysis is based on certain simplifying assumptions such as rigid behavior over supports and simplified tendon/concrete/steel plate interaction. The current objective is to conduct a representative study for a more …

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Right Turn Split: A New Design To Alleviate Weaving On Arterial Streets, Khaled Shaaban Jan 2005

Right Turn Split: A New Design To Alleviate Weaving On Arterial Streets, Khaled Shaaban

Electronic Theses and Dissertations

While weaving maneuvers occur on every type of roadway, most studies have focused on freeway maneuvers. Weaving occurring on non-freeway facilities, such as arterial streets, can cause significant operational problems. Arterial streets weaving typically occur when vehicles coming from a side street at an upstream intersection attempt to enter the main street from one side to reach access points on the opposite site at a downstream intersection by crossing one or more lanes. This dissertation investigates the type of problems occurring on arterial streets due to the weaving movements and recommends a new design to alleviate weaving on arterial streets. …

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A Nostalgic Reconsideration Of The Sublime In Aesthetics, Katherine Rhodes Fields Jan 2005

A Nostalgic Reconsideration Of The Sublime In Aesthetics, Katherine Rhodes Fields

Electronic Theses and Dissertations

No abstract provided.

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The Effect Of Timber Harvesting On Soil Biogeochemical And Physical Properties : Resilience Studies On Disturbed Forests And Their Associated Wetlands, Bikash Rajkarnikar Jan 2005

The Effect Of Timber Harvesting On Soil Biogeochemical And Physical Properties : Resilience Studies On Disturbed Forests And Their Associated Wetlands, Bikash Rajkarnikar

Electronic Theses and Dissertations

No abstract provided.

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Generic And Professional Health Care Beliefs, Expressions And Practices Of Syrian Muslims Living In The Midwestern United States, Hiba Wehbe-Alamah Jan 2005

Generic And Professional Health Care Beliefs, Expressions And Practices Of Syrian Muslims Living In The Midwestern United States, Hiba Wehbe-Alamah

Electronic Theses and Dissertations

The purpose of this ethnonursing study was to discover the generic and professional health care beliefs, expressions, and practices of Syrian Muslims living in the Midwestern United States and to describe the influence of worldview, cultural context, and social structure, such as technological, religious, political, educational, and economical factors on their folk care beliefs and practices. Leininger's Culture Care Theory was used as an orientational framework for this study. Ten key and twenty general informants participated in this study. Several qualitative enablers were used to assist with the collection and analysis of data. QSR NUD*IST 4, a qualitative research software …

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A Comparison Of Decontextualized And Contextualized Reading Skills In Persons With Severe Aphasia, Carey Smith Jan 2005

A Comparison Of Decontextualized And Contextualized Reading Skills In Persons With Severe Aphasia, Carey Smith

Electronic Theses and Dissertations

A repeated measures comparative design compared the reading comprehension accuracy scores of three participants across two conditions: Condition A -- Decontextualized Stimulus Reading Task (DSRT), resembling traditional reading therapy, and Condition B -- Contextual Choice Reading Conversation (CCRC) with a communication partner. In the DSRT condition, participants read a sentence-length question prior to selecting one of 3-to-5 printed responses with no supports. In CCRC, partners presented graphic sentence stimuli representing conversational questions and response choices with the following supports: simultaneous auditory input, supplemental drawings or gestures, natural repetitions, consistent topic, and conversational order. Experimental conditions were administered in counterbalanced order …

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Games People Play: Identity And Relationships In An Online Role-Playing Game, Jennifer Bortle Jan 2005

Games People Play: Identity And Relationships In An Online Role-Playing Game, Jennifer Bortle

Electronic Theses and Dissertations

The following is a study of online relationships and identity formation in Everquest, a multiplayer online role-playing game. Using a phenomenological and reflexive approach, the study seeks to explicate the attractions of this type of online forum, which draws hundreds of thousands of players who spend many hours each week playing the game. Three Everquest players' experiences are considered in light of literature from mainstream psychological, social constructionist, psychodynamic, and cyborg theory, with special focus on the players' reports of the dialogue between player and character, and of the nature of their relationships in Everquest. Subjects participated in a non-directive, …

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Healing Violence In South Africa: A Textual Reading Of Kentridge's 'Drawings For Projection', Vanessa Thompson Jan 2005

Healing Violence In South Africa: A Textual Reading Of Kentridge's 'Drawings For Projection', Vanessa Thompson

Electronic Theses and Dissertations

While the literature appears to understand trauma and violence as experienced singularly, and as effecting intrapsychic changes or reactions, latterly there has been a recognition that this understanding of the term 'trauma' may not be adequate to describe violence suffered over a prolonged period of time. Further, psychology tends to avert our attention from healing by attending to symptomatology. In South Africa, during the apartheid years (1948-1994), violence was constituted by an extraordinary threat to ongoing being and was informed by a totalitarian prejudice. Creative texts, unlike traumatic texts, show how many artists have worked with South African traumas in …

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Eyes In The Text: Surveying The Ocular Aesthetic In Pat Barker's War Trilogy, James Hammond Jan 2005

Eyes In The Text: Surveying The Ocular Aesthetic In Pat Barker's War Trilogy, James Hammond

Electronic Theses and Dissertations

In 1991, British novelist Patricia Barker published Regeneration, the first of three novels that portrayed the exploits of both factual and fictional characters during the darkest days of WWI. Barker's Eye in the Door (1993), followed by The Ghost Road (1995) for which she won the Booker Prize for Fiction, completed the series that explored the effects of combat on the human psyche. What emerges as a dominant feature of Barker's war novels is her depiction of the ocular sense. Reminiscent of Orwellianism, Barker's texts contain a seemingly ubiquitous ocular presence. For example, neurasthenic patients are scrutinized by army psychiatrists, …

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Variability In Detection Of Fecal Coliforms And Escherichia Coli Through American Public Health Association Standard Methods Of Mfc, Mug And Verification Methods And The Differentiation Of Escherichia Coli Through Substrate Utilization Kinetics, Misty Schaubhut Jan 2005

Variability In Detection Of Fecal Coliforms And Escherichia Coli Through American Public Health Association Standard Methods Of Mfc, Mug And Verification Methods And The Differentiation Of Escherichia Coli Through Substrate Utilization Kinetics, Misty Schaubhut

Electronic Theses and Dissertations

No abstract provided.

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Deep Play, Sean Ennis Jan 2005

Deep Play, Sean Ennis

Electronic Theses and Dissertations

No abstract provided.

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Beyond The Death Of The Subject : Suicide In The Works Of Dostoevsky, Camus And Hemingway, William Jared Hogue Jan 2005

Beyond The Death Of The Subject : Suicide In The Works Of Dostoevsky, Camus And Hemingway, William Jared Hogue

Electronic Theses and Dissertations

No abstract provided.

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Honor, Commerce, Suffrage, And Civil Rights, Sean Hughes Jan 2005

Honor, Commerce, Suffrage, And Civil Rights, Sean Hughes

Electronic Theses and Dissertations

No abstract provided.

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New York City Police Officers' Experiences Of The September 11, 2001 Terrorist Attacks: An Existential Psychological Study, Cecile S. Irvine Jan 2005

New York City Police Officers' Experiences Of The September 11, 2001 Terrorist Attacks: An Existential Psychological Study, Cecile S. Irvine

Electronic Theses and Dissertations

The police officers of the NYPD who responded to the scene of the terrorist attacks on the World Trade Center on September 11, 2001 faced a sudden and large-scale catastrophe that caused the deaths of many innocent civilians and threatened their own lives. The present study examines the lived meanings of this experience for three police officers who survived the collapse of the Twin Towers while acting in the performance of their duty. Although a great deal of research has been conducted in the field of psychological trauma, the existential meaning of traumatic events for those that live through them …

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