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Atmospheric Pressure Chemical Vapor Deposition Of Functional Oxide Materials For Crystalline Silicon Solar Cells, Kristopher Davis Jan 2015

Atmospheric Pressure Chemical Vapor Deposition Of Functional Oxide Materials For Crystalline Silicon Solar Cells, Kristopher Davis

Electronic Theses and Dissertations

Functional oxides are versatile materials that can simultaneously enable efficiency gains and cost reductions in crystalline silicon (c-Si) solar cells. In this work, the deposition of functional oxide materials using atmospheric pressure chemical vapor deposition (APCVD) and the integration of these materials into c-Si solar cells are explored. Specifically, thin oxide films and multi-layer film stacks are utilized for the following purposes: (1) to minimize front surface reflectance without increasing parasitic absorption within the anti-reflection coating(s); (2) to maximize internal back reflectance of rear passivated cells, thereby increasing optical absorption of weakly absorbed long wavelength photons (? > 900 nm); (3) …

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Assessing Biofiltration Pretreatment For Ultrafiltration Membrane Processes, Andrea Cumming Jan 2015

Assessing Biofiltration Pretreatment For Ultrafiltration Membrane Processes, Andrea Cumming

Electronic Theses and Dissertations

An engineered biological filtration (biofiltration) process treating a nutrient-enriched, low-alkalinity, organic-laden surface water downstream of conventional coagulation-clarification and upstream of an ultrafiltration (UF) membrane process was assessed for its treatment effectiveness. The impact of biofiltration pretreatment on UF membrane performance was evaluated holistically by investigating the native source water chemistry and extending the analysis into the drinking water distribution system. The biofiltration process was also compared in treatment performance to two alternative pretreatment technologies, including magnetic ion exchange (MIEX®) and granular activated carbon (GAC) adsorption. The MIEX®, GAC adsorption, and biologically active carbon (BAC) filtration pretreatments were integrated with conventional …

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Calibration Of Option Pricing In Reproducing Kernel Hilbert Space, Lei Ge Jan 2015

Calibration Of Option Pricing In Reproducing Kernel Hilbert Space, Lei Ge

Electronic Theses and Dissertations

A parameter used in the Black-Scholes equation, volatility, is a measure for variation of the price of a financial instrument over time. Determining volatility is a fundamental issue in the valuation of financial instruments. This gives rise to an inverse problem known as the calibration problem for option pricing. This problem is shown to be ill-posed. We propose a regularization method and reformulate our calibration problem as a problem of finding the local volatility in a reproducing kernel Hilbert space. We defined a new volatility function which allows us to embrace both the financial and time factors of the options. …

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Modeling And Analysis Of Automated Storage And Retrievals System With Multiple In-The-Aisle Pick Positions, Faraz Ramtin Jan 2015

Modeling And Analysis Of Automated Storage And Retrievals System With Multiple In-The-Aisle Pick Positions, Faraz Ramtin

Electronic Theses and Dissertations

This dissertation focuses on developing analytical models for automated storage and retrieval system with multiple in-the-aisle pick positions (MIAPP-AS/RS). Specifically, our first contribution develops an expected travel time model for different pick positions and different physical configurations for a random storage policy. This contribution has been accepted for publication in IIE Transactions (Ramtin & Pazour, 2014) and was the featured article in the IE Magazine (Askin & Nussbaum, 2014). The second contribution addresses an important design question associated with MIAPP-AS/RS, which is the assignment of items to pick positions in an MIAPP-AS/RS. This contribution has been accepted for publication in …

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The Influence Of Trait Anxiety On Information Processing: An Elaboration Likelihood Study, Michael Appelbaum Jan 2015

The Influence Of Trait Anxiety On Information Processing: An Elaboration Likelihood Study, Michael Appelbaum

Electronic Theses and Dissertations

This study explored the influence of trait anxiety on information processing in persuasive situations, and investigated cognitive load as a mediator of this relationship. The research presented was based off DeBono and McDermott's (1994) framework for exploring trait anxiety and persuasion. The theoretical lens used to explore information processing, the elaboration likelihood model (Petty & Cacioppo, 1986) posits that motivation and ability are necessary components to elaborate on a message. However, very little research has addressed ability variables like trait anxiety. I predicted that students high in trait anxiety would be persuaded by the attractiveness of the source (peripherally) whereas …

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White Light Continuum For Broadband Nonlinear Spectroscopy, Trenton Ensley Jan 2015

White Light Continuum For Broadband Nonlinear Spectroscopy, Trenton Ensley

Electronic Theses and Dissertations

Supercontinuum (SC) generation, oftentimes referred to as white-light continuum (WLC), has been a subject of interest for more than 40 years. From the first observation of WLC in condensed media in the early 1970s to the first observation of WLC in gases in the mid-1980s, much work has been devoted to developing a framework for understanding the complex nature of this phenomenon as well as discovering its utility in various applications. The main effort of this dissertation is to develop a WLC for the purpose of broadband nonlinear spectroscopy and use it in spectroscopic measurements. The ability to generate a …

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The Impact Of User-Generated Interfaces On The Participation Of Users With A Disability In Virtual Environments: Blizzard Entertainment's World Of Warcraft Model, Donald Merritt Jan 2015

The Impact Of User-Generated Interfaces On The Participation Of Users With A Disability In Virtual Environments: Blizzard Entertainment's World Of Warcraft Model, Donald Merritt

Electronic Theses and Dissertations

When discussing games and the experience of gamers those with disabilities are often overlooked. This has left a gap in our understanding of the experience of players with disabilities in virtual game worlds. However there are examples of players with disabilities being very successful in the virtual world video game World of Warcraft, suggesting that there is an opportunity to study the game for usability insight in creating other virtual world environments. This study surveyed World of Warcraft players with disabilities online for insight into how they used interface addons to manage their experience and identity performance in the game. …

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A Study Of The Impact Of Brevard Public School's Peer Coaching Model On Student Achievement Outcomes And Teacher Evaluation Results, Debra Pace Jan 2015

A Study Of The Impact Of Brevard Public School's Peer Coaching Model On Student Achievement Outcomes And Teacher Evaluation Results, Debra Pace

Electronic Theses and Dissertations

This study investigated the effectiveness of a sustained professional development initiative, Brevard's Peer Coaching Model, on improving teacher performance and student achievement in a large Central Florida school district. The study analyzed professional practices scores and value-added scores for teachers who participated in a minimum of six of nine days of professional learning before the study, after year one of the training, and after year two of the training to evaluate growth in professional practices and student achievement, and also compared the scores of BPCM participants to the scores of teachers who did not participate in the study. The findings …

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Two-Photon Absorption In Bulk Semiconductors And Quantum Well Structures And Its Applications, Himansu Pattanaik Jan 2015

Two-Photon Absorption In Bulk Semiconductors And Quantum Well Structures And Its Applications, Himansu Pattanaik

Electronic Theses and Dissertations

The purpose of this dissertation is to provide a study and possible applications of two-photon absorption (2PA), in direct-gap semiconductors and quantum-well (QW) semiconductor structures. One application uses extremely nondegenerate (END) 2PA, for mid-infrared (mid-IR) detection in uncooled semiconductors. The use of END, where the two photons have very different energies gives strong enhancement comapared to degenerate 2PA. This END-2PA enhanced detection is also applied to mid-IR imaging and light detection and ranging (LIDAR) in uncooled direct-gap photodiodes. A theoretical study of degenerate 2PA (D-2PA) in quantum wells, QWs, is presented, along with a new theory of ND 2PA in …

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Principals' Lived Experiences In Childhood Poverty Impacting Resiliency Of Students In Poverty, Jonathan Rasmussen Jan 2015

Principals' Lived Experiences In Childhood Poverty Impacting Resiliency Of Students In Poverty, Jonathan Rasmussen

Electronic Theses and Dissertations

The number of children living in poverty within the United States is on the rise, which translates to more public school students experiencing those risk factors associated with poverty. Given the severity of the negative effect living in poverty has on the likelihood of academic success, paired with the current climate of accountability in U.S. public schools, it is imperative that educational leaders understand how to create a school culture that fosters resilience in students from poverty. The purpose of this study was to examine principals' lived experiences in childhood poverty impacts the decisions they make. More precisely, it examines …

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The Effects Of The Marzano Observation System Training On The Self-Efficacy Of Teacher Observers, Samuel Ashley Jan 2015

The Effects Of The Marzano Observation System Training On The Self-Efficacy Of Teacher Observers, Samuel Ashley

Electronic Theses and Dissertations

This research analyzed the effects of the Marzano Teacher Observation training on the self-efficacy of teacher observers. In this study, seventy-four teacher observers reported their self-efficacy in the areas of evaluating student engagement, evaluating classroom management, and evaluating instructional strategies in pre and post surveys. The results of the surveys were analyzed with a paired samples t-test. This study found that the Marzano Teacher Observation system increases the self-efficacy of teacher observers. This study was delimited to participants of a Marzano Teacher Observation training conducted in the fall of 2014. The findings of this study will inform executive school leaders …

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Aggregation Of Squaraine Dye Derivatives In Solid State Spin-Coated Thin Films, Mohammed Daoudi Jan 2015

Aggregation Of Squaraine Dye Derivatives In Solid State Spin-Coated Thin Films, Mohammed Daoudi

Electronic Theses and Dissertations

Squaraine dyes have been the subject of intensive studies due their unusual electronic properties that make them good candidates for a wide range of applications in various technological fields. They are particularly promising in nonlinear optics, bioimaging for labeling and sensing of biomolecules, as sensitizers for solar energy harvesting in solar cells and organic photovoltaics, two-photon absorbing materials, near-infrared (NIR) emitting fluorescent probes, second harmonic generation organic dyes, and sensitizers for photodynamic therapy among others. In this dissertation, the aggregation behaviors and features of several squaraine dye derivatives in solid state thin films were studied and reported. In the first …

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Chemical Analysis, Databasing, And Statistical Analysis Of Smokeless Powders For Forensic Application, Dana-Marie Dennis Jan 2015

Chemical Analysis, Databasing, And Statistical Analysis Of Smokeless Powders For Forensic Application, Dana-Marie Dennis

Electronic Theses and Dissertations

Smokeless powders are a set of energetic materials, known as low explosives, which are typically utilized for reloading ammunition. There are three types which differ in their primary energetic materials; where single base powders contain nitrocellulose as their primary energetic material, double and triple base powders contain nitroglycerin in addition to nitrocellulose, and triple base powders also contain nitroguanidine. Additional organic compounds, while not proprietary to specific manufacturers, are added to the powders in varied ratios during the manufacturing process to optimize the ballistic performance of the powders. The additional compounds function as stabilizers, plasticizers, flash suppressants, deterrents, and opacifiers. …

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Examining The Social Interactions Of Young Adults With Autism Spectrum Disorders In A Virtual Environment, Jennifer Gallup Jan 2015

Examining The Social Interactions Of Young Adults With Autism Spectrum Disorders In A Virtual Environment, Jennifer Gallup

Electronic Theses and Dissertations

This phenomenological study examined the social interactions during online game play in a virtual environment for five young adults with an autism spectrum disorder (ASD) who attended a large metropolitan university, enrolled in the first 60 credits of a science, technology, engineering, or mathematics (STEM) field of study. Given the evolution of technology and opportunities to socialize in virtual communities, it is becoming increasingly important to understand how young adults with ASD assimilate into new social opportunities that provide supports for extraneous variables such as face-to-face situations. As research begins to emerge on virtual environments there is little research addressed …

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Propagation Failure In Discrete Inhomogeneous Medium Using A Caricature Of The Cubic, Elizabeth Lydon Jan 2015

Propagation Failure In Discrete Inhomogeneous Medium Using A Caricature Of The Cubic, Elizabeth Lydon

Electronic Theses and Dissertations

Spatially discrete Nagumo equations have widespread physical applications, including modeling electrical impulses traveling through a demyelinated axon, an environment typical in multiple scle- rosis. We construct steady-state, single front solutions by employing a piecewise linear reaction term. Using a combination of Jacobi-Operator theory and the Sherman-Morrison formula we de- rive exact solutions in the cases of homogeneous and inhomogeneous diffusion. Solutions exist only under certain conditions outlined in their construction. The range of parameter values that satisfy these conditions constitutes the interval of propagation failure, determining under what circumstances a front becomes pinned in the media. Our exact solutions represent …

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A Study On The Relationships Between Participation In Tutoring And Accountability Measures In One Urban High School, Hector Maestre Jan 2015

A Study On The Relationships Between Participation In Tutoring And Accountability Measures In One Urban High School, Hector Maestre

Electronic Theses and Dissertations

The purpose of this study was to identify relationships between an urban high school*s student participation in an after-school tutoring program and its relationship to accountability measures on the Florida Comprehensive Assessment Test (FCAT) Reading and End of Course (EOC) exams in the 2013-2014 school year. The research aimed to determine the influence of tutoring participation for urban high school students. Participants included students enrolled in one urban high school who participated in the FCAT Reading and EOC assessments and is was identified if they participated in the school tutoring program or not. Quantitative results revealed the relationship between students* …

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Selective Electro-Magnetic Absorbers Based On Metal-Dielectric-Metal Thin-Film Cavities, Janardan Nath Jan 2015

Selective Electro-Magnetic Absorbers Based On Metal-Dielectric-Metal Thin-Film Cavities, Janardan Nath

Electronic Theses and Dissertations

Efficient absorption of light is required for a large number of applications such as thermo-photovoltaics,thermal imaging, bio-sensing, thermal emitters, astronomy, and stealth technology. Strong light absorbers found in nature with high intrinsic losses such as carbon black, metal-black, and carbon nano-tubes etc. are bulky, not design-tunable and are hard to pattern for micro- and nano- devices. We developed thin-film, high performance absorbers in the visible, near-, mid-, long-wave - and far-IR region based on a 3 layer metal-dielectric-metal (MDM) structure. We fabricated a 3-layerMDMabsorber with large band-widths in the visible and near IR spectral range without any lithographic patterning. This …

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Theoretical Study Of Laser Beam Quality And Pulse Shaping By Volume Bragg Gratings, Sergiy Kaim Jan 2015

Theoretical Study Of Laser Beam Quality And Pulse Shaping By Volume Bragg Gratings, Sergiy Kaim

Electronic Theses and Dissertations

The theory of stretching and compressing of short light pulses by the chirped volume Bragg gratings (CBG) is reviewed based on spectral decomposition of short pulses and on the wavelength-dependent coupled wave equations. The analytic theory of diffraction efficiency of a CBG with constant chirp and approximate theory of time delay dispersion are presented. Based on those, we performed comparison of the approximate analytic results with the exact numeric coupled-wave modeling. We also study theoretically various definitions of laser beam width in a given cross-section. Quality of the beam is characterized by the dimensionless beam propagation products (?x???_x)?? , which …

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Five School District Mentor Models For Secondary Mathematics And Science Teachers In A Job Embedded University Teacher Preparation Program, Lisa Karcinski Jan 2015

Five School District Mentor Models For Secondary Mathematics And Science Teachers In A Job Embedded University Teacher Preparation Program, Lisa Karcinski

Electronic Theses and Dissertations

Mentoring was a component of the Resident Teacher Professional Preparation Program (RTP3), a Race to the Top (RTTT) program funded project. RTTT funded efforts reward states that have demonstrated success in raising student achievement and have the best plans to accelerate learning in the future (U.S. Department of Education, 2014). Five Florida school districts implemented different variations of the RTP3 mentor model and due to the unique needs of each school district, context differences in effectiveness may have emerged. The purpose of the study was to determine the differences among the five mentor models, the extent to which these differences …

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Thinking Fast And Missing The Opportunity: An Investigation Into Cognitive Processing Style And Opportunity Recognition, Chaim Letwin Jan 2015

Thinking Fast And Missing The Opportunity: An Investigation Into Cognitive Processing Style And Opportunity Recognition, Chaim Letwin

Electronic Theses and Dissertations

Research on opportunity recognition and entrepreneurial cognition suggests that entrepreneurs are likely to use and potentially benefit from heuristics (Baron, 1998, 2004; Busenitz & Barney, 1997). Some heuristics, particularly well-refined and accurate prototypes, may be valuable to entrepreneurs in recognizing opportunities (Baron, 2004). I seek, however, to consider how other types of heuristics that lead to irrational, biased, and inaccurate judgments (e.g., the betrayal heuristic) relate to opportunity recognition (Baron, 2004; Kahneman & Lovallo, 1993). I specifically consider the underlying causal process through which the use of these types of heuristics diminishes the ability to recognize opportunities. I posit that …

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Spectral Study Of Asteroids And Laboratory Simulation Of Asteroid Organics, Kelsey Hargrove Jan 2015

Spectral Study Of Asteroids And Laboratory Simulation Of Asteroid Organics, Kelsey Hargrove

Electronic Theses and Dissertations

We investigate the spectra of asteroids at near- and mid-infrared wavelengths. In 2010 and 2011 we reported the detection of 3 ?m and 3.2-3.6 ?m signatures on (24) Themis and (65) Cybele indicative of water-ice and complex organics [1] [2] [3]. We further probed other primitive asteroids in the Cybele dynamical group and Themis family, finding diversity in the shape of their 3 ?m [4] [5] [6] and 10 ?m spectral features [4]. These differences indicated mineralogical and compositional variations within these asteroid populations. Also in the mid-infrared region we studied a larger population of asteroids belonging to the Bus …

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Math Remediation For High School Freshmen, Kambiz Borhon Jan 2015

Math Remediation For High School Freshmen, Kambiz Borhon

Electronic Theses and Dissertations

This study is an attempt to address the problem associated with a high percentage of freshman students, at a private Christian high school in Florida, who either fail Algebra 1 or pass with a low percentage rate. As a result, these students either retake Algebra 1 or continue on—being inadequately prepared to successfully pass Geometry and Algebra 2. This study concentrates on the student background knowledge of mathematics, which is among the causes associated with this problem, and proposes remediation. As such, a mathematics remediation course is designed and implemented for a select number of incoming freshmen. This study includes …

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Synthesis Of Fluorene-Based Derivatives, Characterization Of Optical Properties And Their Applications In Two-Photon Fluorescence Imaging And Photocatalysis, Grace Githaiga Jan 2015

Synthesis Of Fluorene-Based Derivatives, Characterization Of Optical Properties And Their Applications In Two-Photon Fluorescence Imaging And Photocatalysis, Grace Githaiga

Electronic Theses and Dissertations

The two-photon absorption (2PA) phenomenon has attracted attention from various fields ranging from chemistry and biology to optics and engineering. Two of the common NLO applications in which organic materials have been used are three-dimensional (3D) fluorescence imaging and optical power limiting. Two-photon absorbing materials are, therefore, in great demand to meet the needs of emerging technologies. Organic molecules show great promise to meet this need as they can be customized through molecular engineering, and as the development of two-photon materials that suit practical application intensifies, so does research to meet this need. However, there remains some uncertainty in the …

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Conservation Laws And Electromagnetic Interactions, Veerachart Kajorndejnukul Jan 2015

Conservation Laws And Electromagnetic Interactions, Veerachart Kajorndejnukul

Electronic Theses and Dissertations

Aside from energy, light carries linear and angular momenta that can be transferred to matter. The interaction between light and matter is governed by conservation laws that can manifest themselves as mechanical effects acting on both matter and light waves. This interaction permits remote, precise, and noninvasive manipulation and sensing at microscopic levels. In this dissertation, we demonstrated for the first time a complete set of opto-mechanical effects that are based on nonconservative forces and act at the interface between dielectric media. Without structuring the light field, forward action is provided by the conventional radiation pressure while a backward movement …

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Fostering College Student Success: An Analysis Of The Educational Outcomes Of Florida College Students Utilizing Relative Caregiver, Road-To-Independence, And Adoption Tuition Exemptions, Lauren Murray Jan 2015

Fostering College Student Success: An Analysis Of The Educational Outcomes Of Florida College Students Utilizing Relative Caregiver, Road-To-Independence, And Adoption Tuition Exemptions, Lauren Murray

Electronic Theses and Dissertations

This study investigated the educational outcomes of foster care youth utilizing the Road to Independence, Adopted from DCF, and Relative Caregiver tuition exemptions to pursue enrollment in Florida's state college system during the 2012-2013 academic year. An extensive literature review was conducted to examine the history of foster care, examine a contemporary portrait of the American foster care system, and the adult outcomes of former foster care. Federal and state policies impacting the population, campus support initiatives at colleges nationwide and the concept of resilience were also explored. In conjunction with the Florida Department of Education's Division of Accountability, Research …

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A Theoretical And Experimental Investigation Of The Physical And Chemical Properties Of Solid Nanoscale Interfaces, Jeronimo Matos Jan 2015

A Theoretical And Experimental Investigation Of The Physical And Chemical Properties Of Solid Nanoscale Interfaces, Jeronimo Matos

Electronic Theses and Dissertations

With the emerging interest in nanoscale materials, the fascinating field of surface science is rapidly growing and presenting challenges to the design of both experimental and theoretical studies. The primary aim of this dissertation is to shed some light on the physical and chemical properties of selected nanoscale materials at the interface. Furthermore, we will discuss the effective application of cutting edge theoretical and experimental techniques that are invaluable tools for understanding the systems at hand. To this effect, we use density functional theory (DFT) with the inclusion of van der Waals (vdW) interactions to study the effect of long-range …

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Vanadium Oxide Microbolometers With Patterned Gold Black Or Plasmonic Resonant Absorbers, Evan Smith Jan 2015

Vanadium Oxide Microbolometers With Patterned Gold Black Or Plasmonic Resonant Absorbers, Evan Smith

Electronic Theses and Dissertations

High sensitivity uncooled microbolometers are necessary to meet the needs of the next generation of infrared detectors, which seek low power consumption and production cost without sacrificing performance. Presented here is the design, fabrication, and characterization of a microbolometer with responsivity enhanced by novel highly absorptive coatings. The device utilizes a gold-doped vanadium oxide film in a standard air bridge design. Performance estimations are calculated from current theory, and efforts to maximize signal to noise ratio are shown and evaluated. Most notably, presented are the experimental results and analysis from the integration of two different absorptive coatings: a patterned gold …

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Tiling With Polyominoes, Polycubes, And Rectangles, Michael Saxton Jan 2015

Tiling With Polyominoes, Polycubes, And Rectangles, Michael Saxton

Electronic Theses and Dissertations

In this paper we study the hierarchical structure of the 2-d polyominoes. We introduce a new infinite family of polyominoes which we prove tiles a strip. We discuss applications of algebra to tiling. We discuss the algorithmic decidability of tiling the infinite plane Z x Z given a finite set of polyominoes. We will then discuss tiling with rectangles. We will then get some new, and some analogous results concerning the possible hierarchical structure for the 3-d polycubes.

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Translocation Of A Semiflexible Polymer Through A Nanopore, Ramesh Adhikari Jan 2015

Translocation Of A Semiflexible Polymer Through A Nanopore, Ramesh Adhikari

Electronic Theses and Dissertations

The transport of a biomolecule through a nanopore occurs in many biological functions such as, DNA or RNA transport across nuclear pores and the translocation of proteins across the eukaryotic endoplasmic reticulum. In addition to the biological processes, it has potential applications in technology such as, drug delivery, gene therapy, and single molecule sensing. The DNA translocation through a synthetic nanopore device is considered as the basis for cheap and fast sequencing technology. Motivated by the experimental advances, many theoretical models have been developed. In this thesis, we explore the dynamics of driven translocation of a semiflexible polymer through a …

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Photon Statistics In Disordered Lattices, Hasan Kondakci Jan 2015

Photon Statistics In Disordered Lattices, Hasan Kondakci

Electronic Theses and Dissertations

Propagation of coherent waves through disordered media, whether optical, acoustic, or radio waves, results in a spatially redistributed random intensity pattern known as speckle -- a statistical phenomenon. The subject of this dissertation is the statistics of monochromatic coherent light traversing disordered photonic lattices and its dependence on the disorder class, the level of disorder and the excitation configuration at the input. Throughout the dissertation, two disorder classes are considered, namely, diagonal and off-diagonal disorders. The latter exhibits disorder-immune chiral symmetry -- the appearance of the eigenmodes in skew-symmetric pairs and the corresponding eigenvalues in opposite signs. When a disordered …

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