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Theoretical Studies Of Nanostructure Formation And Transport On Surfaces, Maral Aminpour Jan 2013

Theoretical Studies Of Nanostructure Formation And Transport On Surfaces, Maral Aminpour

Electronic Theses and Dissertations

This dissertation undertakes theoretical and computational research to characterize and understand in detail atomic configurations and electronic structural properties of surfaces and interfaces at the nano-scale, with particular emphasis on identifying the factors that control atomic-scale diffusion and transport properties. The overarching goal is to outline, with examples, a predictive modeling procedure of stable structures of novel materials that, on the one hand, facilitates a better understanding of experimental results, and on the other hand, provide guidelines for future experimental work. The results of this dissertation are useful in future miniaturization of electronic devices, predicting and engineering functional novel nanostructures. …

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Solid Phase Extraction Room Temperature Fluorescence Spectroscopy For The Direct Quantification Of Monohydroxy Metabolites Of Polycyclic Aromatic Hydrocarbons In Urine Samples, Korina Jesusa Calimag Jan 2013

Solid Phase Extraction Room Temperature Fluorescence Spectroscopy For The Direct Quantification Of Monohydroxy Metabolites Of Polycyclic Aromatic Hydrocarbons In Urine Samples, Korina Jesusa Calimag

Electronic Theses and Dissertations

Polycyclic aromatic hydrocarbons (PAH) are important environmental pollutants generally formed during incomplete combustion of organic matter containing carbon and hydrogen. Introduced into the human body by adsorption through the skin, ingestion or inhalation, the biotransformation processes of PAH lead to the formation of multiple metabolites. Due to the short elimination lifetime from the body, the quantitative determination of monohydroxy-PAH (OH-PAH) in urine samples provides accurate information on recent exposure to environmental PAH. Urine analysis of OH-PAH with established methodology relies on sample clean-up and pre-concentration followed by chromatographic separation and quantification. Although chromatographic techniques provide reliable results in the analysis …

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Remediation Of Polychlorinated Biphenyl (Pcb) Contaminated Building Materials Using Non-Metal And Activated Metal Treatment Systems, Tamra Legron-Rodriguez Jan 2013

Remediation Of Polychlorinated Biphenyl (Pcb) Contaminated Building Materials Using Non-Metal And Activated Metal Treatment Systems, Tamra Legron-Rodriguez

Electronic Theses and Dissertations

PCBs are recalcitrant compounds of no known natural origin that persist in the environment despite their ban by the United States Environmental Protection Agency in 1979 due to negative health effects. Transport of PCBs from elastic sealants into concrete, brick, and granite structures has resulted in the need for a technology capable of removing these PCBs from the materials. This research investigated the use of a nonmetal treatment system (NMTS) and an activated metal treatment system (AMTS) for the remediation and degradation of PCBs from concrete, brick, and granite affixed with PCB-laden caulking. The adsorption of PCBs onto the components …

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Enhanced Two-Photon Absorption In A Squaraine-Fluorene-Squaraine Dye: Design, Synthesis, Photophysical Properties, And Solvatochromic Behavior, William Moreshead Jan 2013

Enhanced Two-Photon Absorption In A Squaraine-Fluorene-Squaraine Dye: Design, Synthesis, Photophysical Properties, And Solvatochromic Behavior, William Moreshead

Electronic Theses and Dissertations

The discovery of any new technology is usually accompanied by a need for new or improved materials which make that technology useful in practical applications. In the case of two-photon absorption (2PA) this has truly been the case. Since its first demonstration in 1961, there has been an ever increasing quest to understand the relationships between two-photon absorption and the structure of two-photon absorbing materials. This quest has been motivated by the many applications for 2PA which have been reported, including fluorescence bioimaging, 3D microfabrication, 3D optical data storage, upconverted lasing, and photodynamic therapy. The work presented in this dissertation …

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Development Of Micro Volume Dna And Rna Profiling Assays To Identify The Donor And Tissue Source Of Origin Of Trace Forensic Biological Evidence, Brittany Morgan Jan 2013

Development Of Micro Volume Dna And Rna Profiling Assays To Identify The Donor And Tissue Source Of Origin Of Trace Forensic Biological Evidence, Brittany Morgan

Electronic Theses and Dissertations

In forensic casework analysis it is necessary to obtain genetic profiles from increasingly smaller amounts of biological material left behind by perpetrators of crime. The ability to obtain profiles from trace biological evidence is demonstrated with so-called ‘touch DNA evidence’ which is perceived to be the result of DNA obtained from shed skin cells transferred from donor to an object or person during physical contact. However, the current method of recovery of trace DNA involves cotton swabs or adhesive tape to sample an area of interest. This "blindswabbing" approach may result in the recovery of biological material from different individuals …

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Squaraine Dyes, Design And Synthesis For Various Functional Materials Applications, Yuanwei Zhang Jan 2013

Squaraine Dyes, Design And Synthesis For Various Functional Materials Applications, Yuanwei Zhang

Electronic Theses and Dissertations

This dissertation contains the synthesis and characterization of squaraine based new functional materials. In the first part of this thesis work, a water soluble benzothiazolium squaraine dye was synthesized with pyridium pendents, and controlled aggregation properties were achieved. After formation of partially reversible J-aggregation on a polyelectrolyte (poly(acryl acid) sodium salt) template, the nonlinear, two-photon absorption cross section per repeat unit was found to be above 30-fold enhanced compared with nonaggregate and/or low aggregates. Using a similar strategy, sulfonate anions were introduced into the squaraine structure, and the resulting compounds exhibited good water solubilities. A ‘turn on’ fluorescence was discovered …

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Quasi-Experimental Study: The Effects Of Virtual Covert Audio Coaching On Teachers' Transfer Of Knowledge From Professional Development To Classroom Practice, Marilyn Jackson-Lee Jan 2013

Quasi-Experimental Study: The Effects Of Virtual Covert Audio Coaching On Teachers' Transfer Of Knowledge From Professional Development To Classroom Practice, Marilyn Jackson-Lee

Electronic Theses and Dissertations

A quasi-experimental multiple time series design was used to analyze and compare the impact of two types of instructional coaching, face-to-face and virtual covert audio provided with Bluetooth technology, on teacher transfer of knowledge learned in professional development into classroom practice. Teacher transfer across baseline, intervention, and maintenance phases was analyzed. The study was conducted at a public elementary school in a Florida suburban school district with approximately 750 students. Twelve teachers were randomly selected from teachers who volunteered to attend professional development. Six teachers (one from each grade level K-5) in the treatment group received virtual covert audio coaching. …

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Deconstructing Differences In Effectiveness Of Reading Teachers Of Ninth Grade Non-Proficient Readers In One Florida School District, Jason Wysong Jan 2013

Deconstructing Differences In Effectiveness Of Reading Teachers Of Ninth Grade Non-Proficient Readers In One Florida School District, Jason Wysong

Electronic Theses and Dissertations

This study was undertaken to identify specific instructional and professional differences between the most effective and least effective teachers of ninth grade students enrolled in intensive reading courses in one Florida school district. Teachers from eleven schools were invited to complete a survey that included categorical, Likert, and openended response items. Principals and assistant principals at these schools were also invited to complete a similar survey. Teacher respondents were then divided into three effectiveness groups based on the percentage of their students who met 2011-2012 FCAT performance targets established by Florida’s value-added learning growth model. Inferential statistics were used to …

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Numerical Simulations For The Flow Of Rocket Exhaust Through A Granular Medium, Kristina Kraakmo Jan 2013

Numerical Simulations For The Flow Of Rocket Exhaust Through A Granular Medium, Kristina Kraakmo

Electronic Theses and Dissertations

Physical lab experiments have shown that the pressure caused by an impinging jet on a granular bed has the potential to form craters. This poses a danger to landing success and nearby spacecraft for future rocket missions. Current numerical simulations for this process do not accurately reproduce experimental results. Our goal is to produce improved simulations to more accurately and effi- ciently model the changes in pressure as gas flows through a porous medium. A two-dimensional model in space known as the nonlinear Porous Medium Equation as it is derived from Darcy’s law is used. An Alternating-Direction Implicit (ADI) temporal …

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Engineering And Application Of Ultrafast Laser Pulses And Filamentation In Air, Nicholas Barbieri Jan 2013

Engineering And Application Of Ultrafast Laser Pulses And Filamentation In Air, Nicholas Barbieri

Electronic Theses and Dissertations

Continuing advances in laser and photonic technology has seen the development of lasers with increasing power and increasingly short pulsewidths, which have become available over an increasing range of wavelengths. As the availability of laser sources grow, so do their applications. To make better use of this improving technology, understanding and controlling laser propagation in free space is critical, as is understanding the interaction between laser light and matter. The need to better control the light obtained from increasingly advanced laser sources leads to the emergence of beam engineering, the systematic understanding and control of light through refractive media and …

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Terrorism: The Effect Of Positive Social Sanctions, Curtis Hibbert Jan 2013

Terrorism: The Effect Of Positive Social Sanctions, Curtis Hibbert

Electronic Theses and Dissertations

Research shows that relative deprivation, mental illness, culture, ideology, and various forms of social learning are often identified as factors that can lead an individual to terrorism. However, understanding the value of influences in the form of positive social sanctions through social contact has not been fully explored throughout terrorist studies. In regards to influencing behavior, positive social sanctions elicit a desired behavior which is reinforced through praise or rewards. By utilizing a case study approach, this thesis looks to determine the significance of positive social sanctions through social contact on select individuals who have committed an act of terror …

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Ytterbium-Doped Fiber-Seeded Thin-Disk Master Oscillator Power Amplifier Laser System, Christina Willis-Ott Jan 2013

Ytterbium-Doped Fiber-Seeded Thin-Disk Master Oscillator Power Amplifier Laser System, Christina Willis-Ott

Electronic Theses and Dissertations

Lasers which operate at both high average power and energy are in demand for a wide range of applications such as materials processing, directed energy and EUV generation. Presented in this dissertation is a high-power 1 μm ytterbium-based hybrid laser system with temporally tailored pulse shaping capability and up to 62 mJ pulses, with the expectation the system can scale to higher pulse energies. This hybrid system consists of a low power fiber seed and pre-amplifier, and a solid state thin-disk regenerative amplifier. This system has been designed to generate high power temporally tailored pulses on the nanosecond time scale. …

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High Energy, High Average Power, Picosecond Laser Systems To Drive Few-Cycle Opcpa, Andreas Vaupel Jan 2013

High Energy, High Average Power, Picosecond Laser Systems To Drive Few-Cycle Opcpa, Andreas Vaupel

Electronic Theses and Dissertations

The invention of chirped-pulse amplification (CPA) in 1985 led to a tremendous increase in obtainable laser pulse peak intensities. Since then, several table-top, Ti:sapphire-based CPA systems exceeding the 100 TW-level with more than 10 W average power have been developed and several systems are now commercially available. Over the last decade, the complementary technology of optical parametric chirped-pulse amplification (OPCPA) has improved in its performance to a competitive level. OPCPA allows direct amplification of an almost-octave spanning bandwidth supporting few-cycle pulse durations at center wavelengths ranging from the visible to the mid-IR. The current record in peak power from a …

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Pulsed Tm-Fiber Laser For Mid-Ir Generation, Pankaj Kadwani Jan 2013

Pulsed Tm-Fiber Laser For Mid-Ir Generation, Pankaj Kadwani

Electronic Theses and Dissertations

The thulium fiber laser has gained interest due to its long emission wavelength, large bandwidth (~1.8 – 2.1 µm), high efficiencies (~60 %), and high output power levels both in cw as well as pulsed regimes. Applications like remote sensing, machining, medical tissue ablation, and mid-infrared generation benefit from high peak power thulium laser sources. Pulsed thulium fiber laser systems are advancing rapidly towards higher peak power levels and are becoming the preferred sources for these applications. This dissertation work describes the development of novel nanosecond pulsed thulium fiber laser systems with record high peak power levels targeting mid-infrared generation. …

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Attention Must Be Paid: A Critical Study Of The Non-Traditional Leading Man In Twentieth Century Drama, Trevin Cooper Jan 2013

Attention Must Be Paid: A Critical Study Of The Non-Traditional Leading Man In Twentieth Century Drama, Trevin Cooper

Electronic Theses and Dissertations

The role of the non-traditional leading man has painted a strong image which mirrors the cultural development of our identities; we turn to these men/characters to understand who, or why, we are. Their contributions require acknowledgement. This thesis is a study of the vital role the non-traditional leading man has played in the evolution of twentieth-century theatre. It will examine, through the use of ten plays, one from every decade of the twentieth century, and twelve male roles, the theory that some of the greatest leading male characters in modern theatre are not epitomized by the qualities identified with the …

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Can One Hear...? An Exploration Into Inverse Eigenvalue Problems Related To Musical Instruments, Christine Adams Jan 2013

Can One Hear...? An Exploration Into Inverse Eigenvalue Problems Related To Musical Instruments, Christine Adams

Electronic Theses and Dissertations

The central theme of this thesis deals with problems related to the question, “Can one hear the shape of a drum?” first posed formally by Mark Kac in 1966. More precisely, can one determine the shape of a membrane with fixed boundary from the spectrum of the associated differential operator? For this paper, Kac received both the Lester Ford Award and the Chauvant Prize of the Mathematical Association of America. This problem has received a great deal of attention in the past forty years and has led to similar questions in completely different contexts such as “Can one hear the …

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Dynamical Invariants And The Fluid Impulse In Plasma Models, Martin Michalak Jan 2013

Dynamical Invariants And The Fluid Impulse In Plasma Models, Martin Michalak

Electronic Theses and Dissertations

Much progress has been made in understanding of plasmas through the use of the MHD equations and newer models such as Hall MHD and electron MHD. As with most equations of fluid behavior, these equations are nonlinear, and no general solutions can be found. The use of invariant structures allows limited predictions of fluid behavior without requiring a full solution of the underlying equations. The use of gauge transformation can allow the creation of new invariants, while differential geometry offers useful tools for constructing additional invariants from those that are already known. Using these techniques, new geometric, integral and topological …

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Who Are We Educating? Why Undergraduate Students Choose To Major In Communication, Christopher J. Carpenter, Bree Mcewan Jan 2013

Who Are We Educating? Why Undergraduate Students Choose To Major In Communication, Christopher J. Carpenter, Bree Mcewan

Journal of the Association for Communication Administration

This study examined student traits and major characteristics that might lead students to choose communication as a major by collecting survey responses from 476 undergraduate students. Attitudes about the major and potential jobs, expected norms from parents, and areas of perceived behavioral control based on student anxieties were analyzed as predictors of choosing the communication major. Short term benefits of taking communication classes as well as the long-term benefits predicted students’ intention of graduating with a communication major. The perception that the major required little math was associated with choosing the major for those higher in math anxiety.

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Complete Issue Volume 32 Issue 1 Jan 2013

Complete Issue Volume 32 Issue 1

Journal of the Association for Communication Administration

This is the complete issue for Volume 32, Issue 1 of the Journal of the Association for Communication Administration.

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Iterative Adaptive Solar Tracking Having Variable Step Size, Wasfy Mikhael, Issa Batarseh, Nasser Kutkut, Raghuram Ranganathan Dec 2012

Iterative Adaptive Solar Tracking Having Variable Step Size, Wasfy Mikhael, Issa Batarseh, Nasser Kutkut, Raghuram Ranganathan

UCF Patents

A system controller for position controlling a photovoltaic (PV) panel in a PV system including a power sensor sensing output power (P), and a motor for positioning the PV panel. The system controller includes a computing device having memory that provides motor control signal and implements an iterative adaptive control (IAC) algorithm stored in the memory for adjusting an angle of the PV panel. The IAC algorithm includes an iterative relation that relates P at current time k (P(k)), its elevation angle at k (?s(k)), P after a next step (P(k+1)) and its elevation angle at k+1(?s(k+1)). The IAV algorithm …

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Systems And Method For Performing Gabor-Domain Optical Coherence Microscopy, Jannick Rolland, Panomsak Meemon Dec 2012

Systems And Method For Performing Gabor-Domain Optical Coherence Microscopy, Jannick Rolland, Panomsak Meemon

UCF Patents

In one embodiment, imaging a medium under evaluation includes generating acquired images of the medium, each acquired image comprising a cross-sectional image along a lateral and a depth direction of the medium that results from scanning the medium at a different depths, filtering each acquired image to remove out-of-focus portions of the images and generate filtered images, and merging the filtered images to form a high-resolution fused image.

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Electronic Compensation Of Impairments Using Wavelet Filters For Backward Propagation, Guifang Li, Gilad Goldfarb Dec 2012

Electronic Compensation Of Impairments Using Wavelet Filters For Backward Propagation, Guifang Li, Gilad Goldfarb

UCF Patents

With the goal of reducing the number of operations required for digital backward-propagation used for fiber impairment compensation, wavelets-based filtering in digital backward-propagation is presented. The wavelets-based design relies on signal decomposition using time-limited functions and hence is more compatible with the dispersion operator, which is also time-limited. This is in comparison with inverse-Fourier filter design which by definition is not time-limited due to the use of harmonic functions for signal decomposition. Artificial, after-the-fact windowing may be employed in this case; however only a limited amount of saving in number of operations is achieved, compared to the wavelets-base filter design. …

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Perceptions Of Preservice Teacher Candidates Towards Gifted Education Training And Obtaining The Gifted Education Endorsement Certificate In Florida, Zachary Laschober Dec 2012

Perceptions Of Preservice Teacher Candidates Towards Gifted Education Training And Obtaining The Gifted Education Endorsement Certificate In Florida, Zachary Laschober

HIM 1990-2015

According to the Institute for Research and Policy on Acceleration, training in gifted education is inaccessible by teacher candidates in colleges of education in the United States. This study involved the use of questionnaires with 100 teacher candidates enrolled on an introductory course on diversity in education in a Florida university. Teacher candidates responded to a series of items to identify beliefs about giftedness within and outside the context of education as well as the value of training in gifted education for educators. Of the 100 respondents, 79% agreed or strongly agreed with the need for specialized training for educators …

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Art As A Questioning Process, Elizabeth Perez Dec 2012

Art As A Questioning Process, Elizabeth Perez

HIM 1990-2015

The topic of this thesis is, broadly, the crisis of postmodernity and the solution that French rhetorician, Michel Meyer, presents in his theory “problematology.” Meyer looks to relocate the focus of philosophical attention on the question as opposed to the answer. Meyer calls preoccupation with answers “propositionalism.” Propositionalism can be likened to the looming scientism that threatens philosophy in general. Meyer shows, through an examination of questioning, how philosophy can be rescued from obsolescence without being detracted to scientism. Although Meyer’s philosophy is promising, it could not be considered thorough if it did not address art. Using Gilles Deleuze and …

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Imitating Individualized Facial Expressions In A Human-Like Avatar Through A Hybrid Particle Swarm Optimization - Tabu Search Algorithm, Evan Husk Dec 2012

Imitating Individualized Facial Expressions In A Human-Like Avatar Through A Hybrid Particle Swarm Optimization - Tabu Search Algorithm, Evan Husk

HIM 1990-2015

This thesis describes a machine learning method for automatically imitating a particular person's facial expressions in a human-like avatar through a hybrid Particle Swarm Optimization - Tabu Search algorithm. The muscular structures of the facial expressions are measured by Ekman and Friesen's Facial Action Coding System (FACS). Using a neutral face as a reference, the minute movements of the Action Units, used in FACS, are automatically tracked and mapped onto the avatar using a hybrid method. The hybrid algorithm is composed of Kennedy and Eberhart's Particle Swarm Optimization algorithm (PSO) and Glover's Tabu Search (TS). Distinguishable features portrayed on the …

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Humanities, Sciences Must Be United -- For Our Collective Success, Carla Poindexter Nov 2012

Humanities, Sciences Must Be United -- For Our Collective Success, Carla Poindexter

UCF Forum

When Pablo Picasso presented his first cubist paintings to the world, even most educated people thought them hideous and irrational, yet his peers saw them to be ingenious.

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Sandspur, Vol 119, No 05, October 18, 2012, Rollins College Oct 2012

Sandspur, Vol 119, No 05, October 18, 2012, Rollins College

The Rollins Sandspur

Rollins College student newspaper, written by the students and published at Rollins College. The Sandspur started as a literary journal.

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Building Collections In Irs From External Data Sources, Sai Deng, Susan Matveyeva Oct 2012

Building Collections In Irs From External Data Sources, Sai Deng, Susan Matveyeva

Faculty Scholarship and Creative Works

This presentation will address the experiments of building research publication collections from external data sources such as PubMed, IEEE Xplore and Web of Science in the DSpace based institutional repository (IR). To get data from other sources is an alternative way to develop collections for different disciplines since author self-deposit has not become a common practice for institutional repositories. This is also an effort in line with the current metadata cataloging trend of moving from item by item cataloging to batch processing of metadata, repurposing of metadata between different systems and communities, and providing value-added data services to students and …

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The Learning Marketspace, October 2012, Bob Heterick, Carol Twigg Oct 2012

The Learning Marketspace, October 2012, Bob Heterick, Carol Twigg

The Learning MarketSpace (4/03 - 4/14)

No abstract provided.

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Sandspur, Vol 119, No 04, September 27, 2012, Rollins College Sep 2012

Sandspur, Vol 119, No 04, September 27, 2012, Rollins College

The Rollins Sandspur

Rollins College student newspaper, written by the students and published at Rollins College. The Sandspur started as a literary journal.

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