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Measures Of Concordance Of Polynomial Type, Heather Edwards Jan 2004

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 …


Study Of The Excited-State Absorption Properties Of Polymethine Molecules, Richard Stanley Lepkowicz Jan 2004

Study Of The Excited-State Absorption Properties Of Polymethine Molecules, Richard Stanley Lepkowicz

Electronic Theses and Dissertations

This dissertation investigates excited-state nonlinearities in a series of polymethine dyes for the application of nanosecond optical limiting. Optical limiters are devices that for low intensity light exhibit a high linear transmittance, but for high intensity light strongly attenuate the incident radiation. These devices would serve to protect optical sensors from intense laser radiation by clamping the maximum energy allowed through an optical system below the damage threshold of the sensor. The search is ongoing for optical materials that are both broadband and have high damage thresholds to be effective materials for limiting applications. Polymethine dyes are promising compounds due …


Camera System Support For Highway Transportation Using Mobile Devices, Le Minh Jan 2004

Camera System Support For Highway Transportation Using Mobile Devices, Le Minh

Electronic Theses and Dissertations

With the very fast growing technology in wireless, advancement in hardware and the dramatically falling cost of mobile computing devices such as PDA, handheld device, People nowadays can have a personal device that fits in their hand but has computing power as a desktop did few years ago. The same device now is able to communicate over a wireless network and view office document at the same time. The combination of size, power and flexibility makes the personal devices increasingly appear in many aspects of life. In this proposal, we focus on a simple yet useful application of mobile devices …


Macmahon's Master Theorem And Infinite Dimensional Matrix Inversion, Vivian Lola Wong Jan 2004

Macmahon's Master Theorem And Infinite Dimensional Matrix Inversion, Vivian Lola Wong

Electronic Theses and Dissertations

MacMahon's Master Theorem is an important result in the theory of algebraic combinatorics. It gives a precise connection between coefficients of certain power series defined by linear relations. We give a complete proof of MacMahon's Master Theorem based on MacMahon's original 1960 proof. We also study a specific infinite dimensional matrix inverse due to C. Krattenthaler.


Asymptotic Formulas For Large Arguments Of Hypergeometric-Type Functio, Adam Heck Jan 2004

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.


Smoothing Parameter Selection In Nonparametric Functional Estimation, Mohamed Amezziane Jan 2004

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.


The Wave Structure Function And Temporal Frequency Spread In Weak To Strong Optical Turbulence, Aaron J. Masino Jan 2004

The Wave Structure Function And Temporal Frequency Spread In Weak To Strong Optical Turbulence, Aaron J. Masino

Electronic Theses and Dissertations

This paper presents analytic expressions for the wave structure function, frequency spread of the temporal frequency spectrum, and the temporal frequency spectrum of optical signals propagating through a random medium, specifically the Earth’s atmosphere. The results are believed to be valid for all optical turbulence conditions. These expressions are developed using the Rytov approximation method. Generally, the validity of statistical quantities obtained via this method is restricted to conditions of weak optical turbulence. However, in this work, by using a modification of the effective atmospheric spectral model presented by Andrews et al. for scintillation index, wave structure function expressions have …


Electron Injection-Induced Effects In Iii-Nitrides: Physics And Applications, William Charles Burdett Jan 2004

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 …


Individual Carbon Nanotube Probes And Field Emitters Fabrication And T, Guangyu Chai Jan 2004

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 …


The Use Of Pyrosequencing For The Analysis Of Y Chromosome Single Nucleotide Polymorphisms, Jeremy Charles Fletcher Jan 2004

The Use Of Pyrosequencing For The Analysis Of Y Chromosome Single Nucleotide Polymorphisms, Jeremy Charles Fletcher

Electronic Theses and Dissertations

The potential value of the Y chromosome for forensic applications has been recognized for some time with the current work dedicated to Short Tandem Repeat analysis and Single Nucleotide Polymorphism (SNP) discovery. This study examined the ability of two different SNP analysis methods to determine if they could be utilized in forensic applications and ultimately be developed into an established system for Y chromosome SNP analysis. This study examined two principle SNP analysis systems: single base extension and Pyrosequencing. Pyrosequencing was determined to be superior to single base extension, due to the wealth of information provided with sequencing and the …


The Design And Development Of A Comprehensive 49 Locus Y-Str Database For Major U.S. Populations, Paulina Niki Berdos Jan 2004

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 …


Stability And Recovery Of Rna In Biological Stains, Mindy Eileen Setzer Jan 2004

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, …


New Organic/Inorganic Hybrid Sol-Gel Nanocomposite Materials For Raman Gain In Fiber Optics, Stephen James Andrasik Jan 2004

New Organic/Inorganic Hybrid Sol-Gel Nanocomposite Materials For Raman Gain In Fiber Optics, Stephen James Andrasik

Electronic Theses and Dissertations

The recent increased availability of additional wavelengths in the telecommunications window of about 1300-1600 nm has generated an interest in new optical materials and devices that can operate outside the normally used regions of 840 nm, 1310 nm, and 1550 nm. Specifically, methods to amplify fiber optical data transmission in the regions where there is limited or no existing methods to achieve amplification is of interest in the chemistry and photonic communities. Raman gain is one method that has been proposed to passively amplify optical data transmission through a distributed process. Amplification is obtained through a nonlinear light scattering process …


Block Copolymer Stabilized Self-Assembled Magnetic Nanoparticles, Li Zhang Jan 2004

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 …


Method For Determination Of Singlet Oxygen Quantum Yields For New Fluorene-Based Photosensitizers In Aqueous Media For The Advancement Of Photodynamic Therapy, Wade William Grabow Jan 2004

Method For Determination Of Singlet Oxygen Quantum Yields For New Fluorene-Based Photosensitizers In Aqueous Media For The Advancement Of Photodynamic Therapy, Wade William Grabow

Electronic Theses and Dissertations

Photodynamic therapy (PDT) has been investigated over the past three decades and is currently an approved therapeutic modality for skin cancer, the treatment of superficial bladder, early lung and advanced esophageal cancers, and age-related macular degeneration in a number of countries. In PDT, the absorption of light by a chromophore generates cytotoxic species such as reactive singlet oxygen, leading to irreversible destruction of the treated tissue. The measurement of the singlet oxygen quantum yield is an important determinant used to evaluate the efficiency of new photodynamic therapy agents developed in the laboratory, to screen potential photosensitizers in aqueous media.The singlet …


High Performance Data Mining Techniques For Intrusion Detection, Muazzam Ahmed Siddiqui Jan 2004

High Performance Data Mining Techniques For Intrusion Detection, Muazzam Ahmed Siddiqui

Electronic Theses and Dissertations

The rapid growth of computers transformed the way in which information and data was stored. With this new paradigm of data access, comes the threat of this information being exposed to unauthorized and unintended users. Many systems have been developed which scrutinize the data for a deviation from the normal behavior of a user or system, or search for a known signature within the data. These systems are termed as Intrusion Detection Systems (IDS). These systems employ different techniques varying from statistical methods to machine learning algorithms. Intrusion detection systems use audit data generated by operating systems, application softwares or …


Fast Algorithms For Fragment Based Completion In Images Of Natural Scenes, Siddharth Rajkumar Borikar Jan 2004

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 …


Mitochondrial Dna Analysis By Pyrosequencing, Patsy-Ann Susan Hastings Jan 2004

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 …


The Use Of Filters In Topology, Abdellatif Dasser Jan 2004

The Use Of Filters In Topology, Abdellatif Dasser

Electronic Theses and Dissertations

Sequences are sufficient to describe topological properties in metric spaces or, more generally, topological spaces having a countable base for the topology. However, filters or nets are needed in more abstract spaces. Nets are more natural extension of sequences but are generally less friendly to work with since quite often two nets have distinct directed sets for domains. Operations involving filters are set theoretic and generally certain to filters on the same set. The concept of a filter was introduced by H. Cartan in 1937 and an excellent treatment of the subject can be found in N. Bourbaki (1940).


Synthesis And Polymerization Of Bifunctional Five-Membered Cyclic Dithiocarbonates And Their Use As Stabilizers For Magnetic Nan, Mohammed Daoudi Jan 2004

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 Jan 2004

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 …


Neural Networks Satisfying Stone-Weiestrass Theorem And Approximating, Pinal Thakkar Jan 2004

Neural Networks Satisfying Stone-Weiestrass Theorem And Approximating, Pinal Thakkar

Electronic Theses and Dissertations

Neural networks are an attempt to build computer networks called artificial neurons, which imitate the activities of the human brain. Its origin dates back to 1943 when neurophysiologist Warren Me Cello and logician Walter Pits produced the first artificial neuron. Since then there has been tremendous development of neural networks and their applications to pattern and optical character recognition, speech processing, time series prediction, image processing and scattered data approximation. Since it has been shown that neural nets can approximate all but pathological functions, Neil Cotter considered neural network architecture based on Stone-Weierstrass Theorem. Using exponential functions, polynomials, rational functions …


Interactivity And User-Heterogeneity In On Demand Broadcast Video, Mounir Tantaoui El Araki Jan 2004

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 …


Dynamic Shared State Maintenance In Distributed Virtual Environments, Felix George Hamza-Lup Jan 2004

Dynamic Shared State Maintenance In Distributed Virtual Environments, Felix George Hamza-Lup

Electronic Theses and Dissertations

Advances in computer networks and rendering systems facilitate the creation of distributed collaborative environments in which the distribution of information at remote locations allows efficient communication. Particularly challenging are distributed interactive Virtual Environments (VE) that allow knowledge sharing through 3D information. In a distributed interactive VE the dynamic shared state represents the changing information that multiple machines must maintain about the shared virtual components. One of the challenges in such environments is maintaining a consistent view of the dynamic shared state in the presence of inevitable network latency and jitter. A consistent view of the shared scene will significantly increase …


The Proteomics Approach To Evolutionary Computation: An Analysis Of Pr, Ivan Garibay Jan 2004

The Proteomics Approach To Evolutionary Computation: An Analysis Of Pr, Ivan Garibay

Electronic Theses and Dissertations

As the complexity of our society and computational resources increases, so does the complexity of the problems that we approach using evolutionary search techniques. There are recent approaches to deal with the problem of scaling evolutionary methods to cope with highly complex difficult problems. Many of these approaches are biologically inspired and share an underlying principle: a problem representation based on basic representational building blocks that interact and self-organize into complex functions or designs. The observation from the central dogma of molecular biology that proteins are the basic building blocks of life and the recent advances in proteomics on analysis …


Partitioning A Graph In Alliances And Its Application To Data Clustering, Khurram Hassan-Shafique Jan 2004

Partitioning A Graph In Alliances And Its Application To Data Clustering, Khurram Hassan-Shafique

Electronic Theses and Dissertations

Any reasonably large group of individuals, families, states, and parties exhibits the phenomenon of subgroup formations within the group such that the members of each group have a strong connection or bonding between each other. The reasons of the formation of these subgroups that we call alliances differ in different situations, such as, kinship and friendship (in the case of individuals), common economic interests (for both individuals and states), common political interests, and geographical proximity. This structure of alliances is not only prevalent in social networks, but it is also an important characteristic of similarity networks of natural and unnatural …


Sinbad Automation Of Scientific Process: From Hidden Factor Analysis To Theory Synthesis, Olcay Kursun Jan 2004

Sinbad Automation Of Scientific Process: From Hidden Factor Analysis To Theory Synthesis, Olcay Kursun

Electronic Theses and Dissertations

Modern science is turning to progressively more complex and data-rich subjects, which challenges the existing methods of data analysis and interpretation. Consequently, there is a pressing need for development of ever more powerful methods of extracting order from complex data and for automation of all steps of the scientific process. Virtual Scientist is a set of computational procedures that automate the method of inductive inference to derive a theory from observational data dominated by nonlinear regularities. The procedures utilize SINBAD – a novel computational method of nonlinear factor analysis that is based on the principle of maximization of mutual information …


Depth From Defocused Motion, Zarina Myles Jan 2004

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 …


Directory-Based Cache Coherence In Smtp Machines Without Memory Overhead Using Sparse Directories, Anton Kiriwas Jan 2004

Directory-Based Cache Coherence In Smtp Machines Without Memory Overhead Using Sparse Directories, Anton Kiriwas

HIM 1990-2015

As computing power has increased over the past few decades, science and engineering have found more and more uses for this new found computing power. With the advent of multiprocessor machines, we are achieving MIPS and FLOPS ratings previously unthought-of. Distributed shared-memory machines (DSM) are quickly becoming a powerful tool for computing, and the ability to build them from commodity off-the-shelf parts would be a great benefit to computing in general. In the paper entitled, "SMTp: An Architecture for Next-generation Scalable Multi-threading", Heinrich, et al. presents an architecture for a scalable DSM built from slightly modified machines capable of simultaneous …


Automatic Annotation Of Database Images For Query-By-Concept, Nualsawat Hiransakolwong Jan 2004

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 …