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Articles 3151 - 3180 of 3529
Full-Text Articles in Physical Sciences and Mathematics
Depth From Defocused Motion, Zarina Myles
Depth From Defocused Motion, Zarina Myles
Electronic Theses and Dissertations
Motion in depth and/or zooming causes defocus blur. This work presents a solution to the problem of using defocus blur and optical flow information to compute depth at points that defocus when they move. We first formulate a novel algorithm which recovers defocus blur and affine parameters simultaneously. Next we formulate a novel relationship (the blur-depth relationship) between defocus blur, relative object depth and three parameters based on camera motion and intrinsic camera parameters. We can handle the situation where a single image has points which have defocused, got sharper or are focally unperturbed. Moreover, our formulation is valid regardless …
Synthesis And Polymerization Of Bifunctional Five-Membered Cyclic Dithiocarbonates And Their Use As Stabilizers For Magnetic Nan, Mohammed Daoudi
Synthesis And Polymerization Of Bifunctional Five-Membered Cyclic Dithiocarbonates And Their Use As Stabilizers For Magnetic Nan, Mohammed Daoudi
Electronic Theses and Dissertations
Novel bifunctional five-membered cyclic dithiocarbonates (1,3-oxathiolane-2-thione)s were synthesized by the reactions of the corresponding bifunctional oxiranes (epoxides) with carbon disulfide at room temperature with lithium bromide as catalyst. Full characterization of these monomers was performed including elemental analysis, proton and carbon nuclear magnetic resonance (NMR) spectroscopy, gas chromatography-mass spectroscopy, and Fourier transmission infrared (FTIR) spectroscopy. The polyaddition polymerization of 1,3-oxathiolane-2-thione with 1,4-diaminobutane at room temperature resulted in a poly(thiourethane) material. The latter undergoes crosslinking due probably to the autooxidation of the product and formation of disulfide linkages. The five-membered cyclic dithiocarbonate, 5-decyl-1,3-oxathiolane-2-thione, was used a model to demonstrate the usefulness …
Synthesis Of A Novel Family Of Amide Derivatives Of Podocarpic Acid, Dao Nguyen
Synthesis Of A Novel Family Of Amide Derivatives Of Podocarpic Acid, Dao Nguyen
Electronic Theses and Dissertations
As a class, amides are of great interest in biological studies and pharmaceutical application. In this work, podocarpic acid, a natural tricyclic diterpene, derived from Podocarpus species, has been employed to form a novel family of amide derivatives which will later be studied for their potential as new drug leads. Novel amide derivatives of podocarpic acid were synthesized from podocarpic acid in three steps. The first step involved methylation with dimethylsulfate to form methyl-O-methylpodocarpate. This step was followed by iodination with iodine to give iodomethyl-O-methylpodocarpate. Finally amidation with various aliphatic amides using a copper catalyst yielded four amide derivatives of …
Fast Algorithms For Fragment Based Completion In Images Of Natural Scenes, Siddharth Rajkumar Borikar
Fast Algorithms For Fragment Based Completion In Images Of Natural Scenes, Siddharth Rajkumar Borikar
Electronic Theses and Dissertations
Textures are used widely in computer graphics to represent fine visual details and produce realistic looking images. Often it is necessary to remove some foreground object from the scene. Removal of the portion creates one or more holes in the texture image. These holes need to be filled to complete the image. Various methods like clone brush strokes and compositing processes are used to carry out this completion. User skill is required in such methods. Texture synthesis can also be used to complete regions where the texture is stationary or structured. Reconstructing methods can be used to fill in large-scale …
Monolithic Integration Of Dual Optical Elements On High Power Semicond, Laurent Vaissie
Monolithic Integration Of Dual Optical Elements On High Power Semicond, Laurent Vaissie
Electronic Theses and Dissertations
This dissertation investigates the monolithic integration of dual optical elements on high power semiconductor lasers for emission around 980nm wavelength. In the proposed configuration, light is coupled out of the AlGaAs/GaAs waveguide by a low reflectivity grating coupler towards the substrate where a second monolithic optical element is integrated to improve the device performance or functionality. A fabrication process based on electron beam lithography and plasma etching was developed to control the grating coupler duty cycle and shape. The near-field intensity profile outcoupled by the grating is modeled using a combination of finite-difference time domain (FDTD) analysis of the nonuniform …
Block Copolymer Stabilized Self-Assembled Magnetic Nanoparticles, Li Zhang
Block Copolymer Stabilized Self-Assembled Magnetic Nanoparticles, Li Zhang
Electronic Theses and Dissertations
Magnetic materials are currently being developed in the areas of pharmacology and medicinal chemistry for use in applications such as drug delivery and magnetic resonance imaging. Magnetic fluids are being used in audio equipment and hard disk drives. Their suspension in a particular fluid is promoted by the adsorption or reaction of steric or electrostatic stabilizers, which are appropriate for the particular medium. Critical to the success of these magnetic fluids is the development of the steric stabilizers, which must prevent the coagulation of the metal particles. Polymeric materials are one of the most suitable nonmagnetic media to disperse the …
Multiple Scattering Of Light In Inhomogeneous Media And Applications, Claudia Mujat
Multiple Scattering Of Light In Inhomogeneous Media And Applications, Claudia Mujat
Electronic Theses and Dissertations
Light scattering-based techniques are being developed for non-invasive diagnostics of inhomogeneous media in various fields, such as medicine, biology, and material characterization. However, as most media of interest are highly scattering and have a complex structure, it is difficult to obtain a full analytical solution of the scattering problem without introducing approximations and assumptions about the properties of the system under consideration. Moreover, most of the previous studies deal with idealized scattering situations, rarely encountered in practice. This dissertation provides new analytical, numerical, and experimental solutions to describe subtle effects introduced by the properties of the light sources, and by …
The Design And Development Of A Comprehensive 49 Locus Y-Str Database For Major U.S. Populations, Paulina Niki Berdos
The Design And Development Of A Comprehensive 49 Locus Y-Str Database For Major U.S. Populations, Paulina Niki Berdos
Electronic Theses and Dissertations
The establishment of a U.S. National Y-STR reference database from a variety of geographically and ethically diverse populations is essential to facilitate the generation of reliable estimates of Y-STR haplotype frequencies. Such multi-locus haplotype frequencies are required to provide a statistical estimate of the significance of a match. Y-STR loci, unlike traditional STR markers, are not independent of one another and are co-inherited as extended haplotypes of linked markers. The estimation of the frequency of occurrence of a particular haplotype therefore necessitates the use of a counting method, which means that the significance of many matches is dependent upon the …
Object Tracking And Activity Recognition In Video Acquired Using Mobile Cameras, Alper Yilmaz
Object Tracking And Activity Recognition In Video Acquired Using Mobile Cameras, Alper Yilmaz
Electronic Theses and Dissertations
Due to increasing demand on deployable surveillance systems in recent years, object tracking and activity recognition are receiving considerable attention in the research community. This thesis contributes to both the tracking and the activity recognition components of a surveillance system. In particular, for the tracking component, we propose two different approaches for tracking objects in video acquired by mobile cameras, each of which uses a different object shape representation. The first approach tracks the centroids of the objects in Forward Looking Infrared Imagery (FLIR) and is suitable for tracking objects that appear small in airborne video. The second approach tracks …
Electron Injection-Induced Effects In Iii-Nitrides: Physics And Applications, William Charles Burdett
Electron Injection-Induced Effects In Iii-Nitrides: Physics And Applications, William Charles Burdett
Electronic Theses and Dissertations
This research investigated the effect of electron injection in III-Nitrides. The combination of electron beam induced current and cathodoluminescence measurements was used to understand the impact of electron injection on the minority carrier transport and optical properties. In addition, the application of the electron injection effect in optoelectronic devices was investigated. The impact of electron injection on the minority carrier diffusion length was studied at various temperatures in Mg-doped p-GaN, p-Al[subscript x]Ga[subscript 1-x]N, and p-Al[subscript x]Ga[subscript 1-x] N/GaN superlattices. It was found that Lsubscript n] experienced a multi-fold linear increase and that the rate of change of L[subscript n] decreased …
Interactivity And User-Heterogeneity In On Demand Broadcast Video, Mounir Tantaoui El Araki
Interactivity And User-Heterogeneity In On Demand Broadcast Video, Mounir Tantaoui El Araki
Electronic Theses and Dissertations
Video-On-Demand (VOD) has appeared as an important technology for many multimedia applications such as news on demand, digital libraries, home entertainment, and distance learning. In its simplest form, delivery of a video stream requires a dedicated channel for each video session. This scheme is very expensive and non-scalable. To preserve server bandwidth, many users can share a channel using multicast. Two types of multicast have been considered. In a non-periodic multicast setting, users make video requests to the server; and it serves them according to some scheduling policy. In a periodic broadcast environment, the server does not wait for service …
Mitochondrial Dna Analysis By Pyrosequencing, Patsy-Ann Susan Hastings
Mitochondrial Dna Analysis By Pyrosequencing, Patsy-Ann Susan Hastings
Electronic Theses and Dissertations
Mitochondrial DNA (deoxyribo nucleic acid) is typically used in forensic casework when small quantities of high molecular weight quality DNA is not expected to be present thus negating the chances of obtaining usable nuclear DNA. Typical samples that utilized mitochondrial DNA analysis are: hair, bones, teeth, ancient remains (samples or remains that are at least 100 years old) or very old samples (samples that are less than 100 but greater than 10 years old). The current method used to evaluate mitochondrial DNA is Sanger sequencing. Although robust, it is also time consuming and labor intensive, on the other hand pyrosequencing …
Smoothing Parameter Selection In Nonparametric Functional Estimation, Mohamed Amezziane
Smoothing Parameter Selection In Nonparametric Functional Estimation, Mohamed Amezziane
Electronic Theses and Dissertations
This study intends to build up new techniques for how to obtain completely data-driven choices of the smoothing parameter in functional estimation, within the confines of minimal assumptions. The focus of the study will be within the framework of the estimation of the distribution function, the density function and their multivariable extensions along with some of their functionals such as the location and the integrated squared derivatives.
Individual Carbon Nanotube Probes And Field Emitters Fabrication And T, Guangyu Chai
Individual Carbon Nanotube Probes And Field Emitters Fabrication And T, Guangyu Chai
Electronic Theses and Dissertations
Since the discovery of carbon nanotubes (CNT) in 1999, they have attracted much attention due to their unique mechanical and electrical properties and potential applications. Yet their nanosize makes the study of individual CNTs easier said than done. In our laboratory, carbon fibers with nanotube cores have been synthesized with conventional chemical vapor deposition (CVD) method. The single multiwall carbon nanotube (MWNT) sticks out as a tip of the carbon fiber. In order to pick up the individual CNT tips, focused ion beam (FIB) technique is applied to cut and adhere the samples. The carbon fiber with nanotube tip was …
Measures Of Concordance Of Polynomial Type, Heather Edwards
Measures Of Concordance Of Polynomial Type, Heather Edwards
Electronic Theses and Dissertations
A measure of concordance, $\kappa$, is of polynomial type if and only if $\kappa (tA+(1-t)B)$ is a polynomial in $t$ where $A$ and $B$ are 2-copulas. The degree of such a type of measure of concordance is simply the highest degree of the polynomial associated with $\kappa$. In previous work [2], [3], properties of measures of concordance preserving convex sums (equivalently measures of concordance of polynomial type degree one) were established; however, a characterization was not made. Here a characterization is made using approximations involving doubly stochastic matrices. Other representations are provided from this characterization leading naturally to two interpretations …
Asymptotic Formulas For Large Arguments Of Hypergeometric-Type Functio, Adam Heck
Asymptotic Formulas For Large Arguments Of Hypergeometric-Type Functio, Adam Heck
Electronic Theses and Dissertations
Hypergeometric type functions have a long list of applications in the field of sciences. A brief history is given of Hypergeometric functions including some of their applications. A development of a new method for finding asymptotic formulas for large arguments is given. This new method is applied to Bessel functions. Results are compared with previously known methods.
Automatic Annotation Of Database Images For Query-By-Concept, Nualsawat Hiransakolwong
Automatic Annotation Of Database Images For Query-By-Concept, Nualsawat Hiransakolwong
Electronic Theses and Dissertations
As digital images become ubiquitous in many applications, the need for efficient and effective retrieval techniques is more demanding than ever. Query by Example (QBE) and Query by Concept (QBC) are among the most popular query models. The former model accepts example images as queries and searches for similar ones based on low-level features such as colors and textures. The latter model allows queries to be expressed in the form of high-level semantics or concept words, such as "boat" or "car," and finds images that match the specified concepts. Recent research has focused on the connections between these two models …
Toward Building A Social Robot With An Emotion-Based Internal Control, Andreas Marpaung
Toward Building A Social Robot With An Emotion-Based Internal Control, Andreas Marpaung
Electronic Theses and Dissertations
In this thesis, we aim at modeling some aspects of the functional role of emotions on an autonomous embodied agent. We begin by describing our robotic prototype, Cherry--a robot with the task of being a tour guide and an office assistant for the Computer Science Department at the University of Central Florida. Cherry did not have a formal emotion representation of internal states, but did have the ability to express emotions through her multimodal interface. The thesis presents the results of a survey we performed via our social informatics approach where we found that: (1) the idea of having emotions …
Image Based View Synthesis, Jiangjian Xiao
Image Based View Synthesis, Jiangjian Xiao
Electronic Theses and Dissertations
This dissertation deals with the image-based approach to synthesize a virtual scene using sparse images or a video sequence without the use of 3D models. In our scenario, a real dynamic or static scene is captured by a set of un-calibrated images from different viewpoints. After automatically recovering the geometric transformations between these images, a series of photo-realistic virtual views can be rendered and a virtual environment covered by these several static cameras can be synthesized. This image-based approach has applications in object recognition, object transfer, video synthesis and video compression. In this dissertation, I have contributed to several sub-problems …
Polarimetric Characterization Of Random Electromagnetic Beams And Applications, Mircea Mujat
Polarimetric Characterization Of Random Electromagnetic Beams And Applications, Mircea Mujat
Electronic Theses and Dissertations
Polarimetry is one of the principal means of investigating the interaction of light with matter. Theoretical models and experimental techniques are presented in this dissertation for polarimetric characterization of random electromagnetic beams and of signatures of random media in different scattering regimes and configurations. The degree of polarization rather than the full description of the state of polarization is of interest in multiple scattering and free space propagation where the statistical nature and not the deterministic component of light bears the relevant information. A new interferometric technique for determining the degree of polarization by measuring the intensity fluctuations in a …
Quadratic Spatial Soliton Interactions, Ladislav Jankovic
Quadratic Spatial Soliton Interactions, Ladislav Jankovic
Electronic Theses and Dissertations
Quadratic spatial soliton interactions were investigated in this Dissertation. The first part deals with characterizing the principal features of multi-soliton generation and soliton self-reflection. The second deals with two beam processes leading to soliton interactions and collisions. These subjects were investigated both theoretically and experimentally. The experiments were performed by using potassium niobate (KNBO3) and periodically poled potassium titanyl phosphate (KTP) crystals. These particular crystals were desirable for these experiments because of their large nonlinear coefficients and, more importantly, because the experiments could be performed under non-critical-phase-matching (NCPM) conditions. The single soliton generation measurements, performed on KNBO3 by launching the …
Stability And Recovery Of Rna In Biological Stains, Mindy Eileen Setzer
Stability And Recovery Of Rna In Biological Stains, Mindy Eileen Setzer
Electronic Theses and Dissertations
In theory, RNA expression patterns, including the presence and relative abundance of particular RNA species, provide cell and tissue specific information that could be of use to forensic scientists. An mRNA based approach could allow the facile identification of the tissue components present in a body fluid stain and conceivably could supplant the battery of serological and biochemical tests currently employed in the forensic serology laboratory. Some of the potential advantages include greater test specificity, and the ability to perform simultaneous analysis using a common assay format for the presence of all body fluids of forensic interest. In this report, …
Stable Spatial Solitons In Semiconductor Optical Amplifiers, Erdem Ultanir
Stable Spatial Solitons In Semiconductor Optical Amplifiers, Erdem Ultanir
Electronic Theses and Dissertations
A spatial soliton is a shape invariant self guided beam of light or a self induced waveguide. Spatial solitons appear as a result of the balance of diffraction and nonlinear focusing in a system. They have been observed in many different conservative media in the last couple of years. Solitons are ubiquitous, because of the probability of using their interactions in optical data processing, communications etc. Up to now due to the power required to generate the solitons, and the response times of the soliton supporting media, these special waves of nature could not penetrate the applications arena. Semiconductors, with …
Dispersion-Managed Breathing-Mode Semiconductor Mode-Locked Ring Laser, Bojan Resan
Dispersion-Managed Breathing-Mode Semiconductor Mode-Locked Ring Laser, Bojan Resan
Electronic Theses and Dissertations
A novel dispersion-managed breathing-mode semiconductor mode-locked ring laser is developed. The "breathing-mode" designation derives from the fact that intracavity pulses are alternately stretched and compressed as they circulate around the ring resonator. The pulses are stretched before entering the semiconductor gain medium to minimize the detrimental strong integrating self-phase modulation and to enable efficient pulse amplification. Subsequently compressed pulses facilitate bleaching the semiconductor saturable absorber. The intracavity pulse compression ratio is higher than 50. Down chirping when compared to up chirping allows broader mode-locked spectra and shorter pulse generation owing to temporal and spectral semiconductor gain dynamics. Pulses as short …
Towards Direct Writing Of 3-D Photonic Circuits Using Ultrafast Lasers, Arnaud Zoubir
Towards Direct Writing Of 3-D Photonic Circuits Using Ultrafast Lasers, Arnaud Zoubir
Electronic Theses and Dissertations
The advent of ultrafast lasers has enabled micromachining schemes that cannot be achieved by other current techniques. Laser direct writing has emerged as one of the possible routes for fabrication of optical waveguides in transparent materials. In this thesis, the advantages and limitations of this technique are explored. Two extended-cavity ultrafast lasers were built and characterized as the laser sources for this study, with improved performance over existing systems. Waveguides are fabricated in oxide glass, chalcogenide glass, and polymers, these being the three major classes of materials for the telecommunication industry. Standard waveguide metrology is performed on the fabricated waveguides, …
The Use Of Selected Water Quality Parameters To Identify Fecal Coliform Sources In Support Of The Sinking Creek Total Maximum Daily Load., Susana Maria Floresguerra
The Use Of Selected Water Quality Parameters To Identify Fecal Coliform Sources In Support Of The Sinking Creek Total Maximum Daily Load., Susana Maria Floresguerra
Electronic Theses and Dissertations
Sinking Creek, located in upper east Tennessee, is on the 303(d) list for not meeting minimum water quality standards for recreation. A Total Maximum Daily Load (TMDL) for fecal coliforms was developed. The purpose of this study was to investigate the use of water quality parameters to identify areas that contribute to the fecal coliform loading. Concentrations of nitrate-N, orthophosphates, BOD, alkalinity, hardness, and optical brighteners (OB) were monitored at fourteen stations monthly for one year. Site 3 (agricultural region) exhibited the highest average nitrate-N loadings (627.34 mg/sec) and orthophosphate (as PO43-) loadings (84.83 mg/sec). Alkalinity loadings …
Towards A Taxonomy Of Aspect-Oriented Programming., Mario Bernard Hankerson
Towards A Taxonomy Of Aspect-Oriented Programming., Mario Bernard Hankerson
Electronic Theses and Dissertations
As programs continue to increase in size, it has become increasingly difficult to separate concerns into well localized modules, which leads to code tangling- crosscutting code spread throughout several modules. Thus, Aspect-Oriented Programming (AOP) offers a solution to creating modules with little or no crosscutting concerns. AOP presents the notion of aspects, and demonstrates how crosscutting concerns can be taken out of modules and placed into a centralized location.
In this paper, a taxonomy of aspect-oriented programming, as well as a basic overview and introduction of AOP, will be presented in order to assist future researchers in getting started on …
Interworking Methodologies For Dcom And Corba., Edwin Kraus
Interworking Methodologies For Dcom And Corba., Edwin Kraus
Electronic Theses and Dissertations
The DCOM and CORBA standards provide location-transparent access to network-resident software through language independent object interfaces. Although the two standards address similar problems, they do so in incompatible ways: DCOM clients cannot use CORBA objects, and CORBA clients cannot utilize DCOM objects, due to incompatible object system infrastructures.
This thesis investigates the performance of bridging tools to resolve the incompatibilities between DCOM and CORBA, in ways that allow clients to cross object system boundaries. Two kinds of tools were constructed and studied: tools that bind clients to services at compile time, and tools that support dynamic client-server bindings. Data developed …
Towards A Connection Between Linear Embedding And The Poincaré Functional Equation., Tara Marie Michels
Towards A Connection Between Linear Embedding And The Poincaré Functional Equation., Tara Marie Michels
Electronic Theses and Dissertations
Several linear embeddings of the logistic equation, xn+1=axn(1-xn) are considered, the goal being to establish a connection between linear embedding and the Poincaré Functional Equation. In particular, we consider linear embedding schemes in a classical Hardy space.
Survey Of Health Effects Among Residents Adjacent To A National Priority List Site In Ssouthwest Virginia., Danette Haywood
Survey Of Health Effects Among Residents Adjacent To A National Priority List Site In Ssouthwest Virginia., Danette Haywood
Electronic Theses and Dissertations
The Saltville Waste Disposal Site is a National Priority List site used during the 77- year operation (1895–1972) of an electrolytic chlorine and caustic soda plant. A cross-sectional study was conducted to determine disease prevalence among Saltville Medical Center (SMC) patients. Diseases associated with chronic exposures to mercury, arsenic, and lead were reviewed in patient records and these data were analyzed. Ratios of illness observed at the SMC were compared to health studies of similar environmental exposures and disease prevalence among residents of neighboring communities. Prevalence ratios were calculated for residents and non-residents of Saltville who were SMC patients. Saltville …