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Physical Sciences and Mathematics Commons

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2007

Georgia State University

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Full-Text Articles in Physical Sciences and Mathematics

Distributed Web Service Coordination For Collaboration Applications And Biological Workflows, Janaka Lalith Balasooriya Dec 2007

Distributed Web Service Coordination For Collaboration Applications And Biological Workflows, Janaka Lalith Balasooriya

Computer Science Dissertations

In this dissertation work, we have investigated the main research thrust of decentralized coordination of workflows over web services. To address distributed workflow coordination, first we have developed “Web Coordination Bonds” as a capable set of dependency modeling primitives that enable each web service to manage its own dependencies. Web bond primitives are as powerful as extended Petri nets and have sufficient modeling and expressive capabilities to model workflow dependencies. We have designed and prototyped our “Web Service Coordination Management Middleware” (WSCMM) system that enhances current web services infrastructure to accommodate web bond enabled web services. Finally, based on core …


New Multiwavelength Variability And Optical Microvariability Investigations Of X-Ray And Radio Selected Blazars, Margaret Angela Osterman Dec 2007

New Multiwavelength Variability And Optical Microvariability Investigations Of X-Ray And Radio Selected Blazars, Margaret Angela Osterman

Physics and Astronomy Dissertations

The extreme AGN known as blazars can be classified based on their spectral properties into X-ray and radio selected objects, known as XBLs and RBLs, respectively. In this work, the results of new multiwavelength campaigns are presented for two XBLs and two RBLs. Each campaign contains simultaneous observations in the radio, optical, and X-ray regimes. A campaign on a third RBL was completed using near-simultaneous archival radio, optical/IR, and gamma-ray data. The simultaneous multiwavelength behavior exhibited in each campaign was analyzed by examining the multiwavelength variability and using spectral analysis. Observations of prominent optical microvariability were quantitatively analyzed. Previously published …


Slowmo: A Search For Nearby Stars, Misty Adana Brown Dec 2007

Slowmo: A Search For Nearby Stars, Misty Adana Brown

Physics and Astronomy Theses

I report on suspected nearby stars with proper motions 1.0 arcsec > μ ≥ 0.5 arcsec/yr in the southern sky (DEC = −90° to 00°). This sample of slow-motion (SLOWMO) stars complements the work of Jao (2004), who reported on faster moving stars with μ ≥ 1.0 arcsec/yr in the entire sky for his doctoral dissertation, and the work of Finch (2007), who uncovered stars moving slower than 0.5 arcsec/yr between declinations −90° and −47°. Characterizations of SLOWMO systems include trigonometric parallaxes, optical and infrared photometry. For stars without trigonometric parallaxes, colors and apparent magnitudes are used to calculate photometric distance …


Evaluating Variance Of The Model Credibility Index, Yan Xiao Nov 2007

Evaluating Variance Of The Model Credibility Index, Yan Xiao

Mathematics Theses

Model credibility index is defined to be a sample size under which the power of rejection equals 0.5. It applies goodness-of-fit testing thinking and uses a one-number summary statistic as an assessment tool in a false model world. The estimation of the model credibility index involves a bootstrap resampling technique. To assess the consistency of the estimator of model credibility index, we instead study the variance of the power achieved at a fixed sample size. An improved subsampling method is proposed to obtain an unbiased estimator of the variance of power. We present two examples to interpret the mechanics of …


Selecting The Working Correlation Structure By A New Generalized Aic Index For Longitudinal Data, Wei-Lun Lin Nov 2007

Selecting The Working Correlation Structure By A New Generalized Aic Index For Longitudinal Data, Wei-Lun Lin

Mathematics Theses

The analysis of longitudinal data has been a popular subject for the recent years. The growth of the Generalized Estimating Equation (GEE) Liang & Zeger, 1986) is one of the most influential recent developments in statistical practice for this practice. GEE methods are attractive both from a theoretical and a practical standpoint. In this paper, we are interested in the influence of different "working" correlation structures for modeling the longitudinal data. Furthermore, we propose a new AIC-like method for the model assessment which generalized AIC from the point of view of the data generating. By comparing the difference of the …


The Exponential Function Of Matrices, Nathalie Nicholle Smalls Nov 2007

The Exponential Function Of Matrices, Nathalie Nicholle Smalls

Mathematics Theses

The matrix exponential is a very important subclass of functions of matrices that has been studied extensively in the last 50 years. In this thesis, we discuss some of the more common matrix functions and their general properties, and we specifically explore the matrix exponential. In principle, the matrix exponential could be computed in many ways. In practice, some of the methods are preferable to others, but none are completely satisfactory. Computations of the matrix exponential using Taylor Series, Scaling and Squaring, Eigenvectors, and the Schur Decomposition methods are provided.


Contour Based 3d Biological Image Reconstruction And Partial Retrieval, Yong Li Nov 2007

Contour Based 3d Biological Image Reconstruction And Partial Retrieval, Yong Li

Computer Science Dissertations

Image segmentation is one of the most difficult tasks in image processing. Segmentation algorithms are generally based on searching a region where pixels share similar gray level intensity and satisfy a set of defined criteria. However, the segmented region cannot be used directly for partial image retrieval. In this dissertation, a Contour Based Image Structure (CBIS) model is introduced. In this model, images are divided into several objects defined by their bounding contours. The bounding contour structure allows individual object extraction, and partial object matching and retrieval from a standard CBIS image structure. The CBIS model allows the representation of …


Peer-To-Peer Distributed Syd Directory Synchronization In A Proximity-Based Environment, Sunetri Priyanka Dasari Nov 2007

Peer-To-Peer Distributed Syd Directory Synchronization In A Proximity-Based Environment, Sunetri Priyanka Dasari

Computer Science Theses

Distributed directory services are an evolving paradigm in the distributed computing arena. They are a shift from the centralized directory that causes delay and does not scale well to widespread peer-to-peer networks. With networking becoming more pervasive, there is a need to integrate the heterogeneity of device, data and network with the applications that are built on them. SyD or System on Mobile Devices is a middleware that is being used to implement such a distributed directory service. To provide a persistent global view of data, we serialize and synchronize the distributed directories. The SyD APIs provide a high-level environment …


Empirical Likelihood Based Confidence Intervals For The Difference Between Two Sensitivities Of Continuous-Scale Diagnostic Tests At A Fixed Level Of Specificity, Suqin Yao Nov 2007

Empirical Likelihood Based Confidence Intervals For The Difference Between Two Sensitivities Of Continuous-Scale Diagnostic Tests At A Fixed Level Of Specificity, Suqin Yao

Mathematics Theses

Diagnostic testing is essential to distinguish non-diseased individuals from diseased individuals. The sensitivity and specificity are two important indices for the diagnostic accuracy of continuous-scale diagnostic tests. If we want to compare the effectiveness of two tests, it is of interest to construct a confidence interval for the difference of the two sensitivities at a fixed level of specificity. In this thesis, we propose two empirical likelihood based confidence intervals (HBELI and HBELII) for the difference of two sensitivities at a predetermined specificity level. Simulation studies show that when correlation between the two test results exists, HBELI and HBELII intervals …


Empirical Likelihood Confidence Intervals For Generalized Lorenz Curve, Nelly E. Belinga-Hill Nov 2007

Empirical Likelihood Confidence Intervals For Generalized Lorenz Curve, Nelly E. Belinga-Hill

Mathematics Theses

Lorenz curves are extensively used in economics to analyze income inequality metrics. In this thesis, we discuss confidence interval estimation methods for generalized Lorenz curve. We first obtain normal approximation (NA) and empirical likelihood (EL) based confidence intervals for generalized Lorenz curves. Then we perform simulation studies to compare coverage probabilities and lengths of the proposed EL-based confidence interval with the NA-based confidence interval for generalized Lorenz curve. Simulation results show that the EL-based confidence intervals have better coverage probabilities and shorter lengths than the NA-based intervals at 100p-th percentiles when p is greater than 0.50. Finally, two real examples …


Inference For Cox's Regression Model Via A New Version Of Empirical Likelihood, Ali Jinnah Nov 2007

Inference For Cox's Regression Model Via A New Version Of Empirical Likelihood, Ali Jinnah

Mathematics Theses

Cox Proportional Hazard Model is one of the most popular tools used in the study of Survival Analysis. Empirical Likelihood (EL) method has been used to study the Cox Proportional Hazard Model. In recent work by Qin and Jing (2001), empirical likelihood based confidence region is constructed with the assumption that the baseline hazard function is known. However, in Cox’s regression model the baseline hazard function is unspecified. In this thesis, we re-formulate empirical likelihood for the vector of regression parameters by estimating the baseline hazard function. The EL confidence regions are obtained accordingly. In addition, Adjusted Empirical Likelihood (AEL) …


Individual Growth Models Of Change In Peabody Picture Vocabulary Scores Of Children Treated For Brain Tumors, Ying Shen Nov 2007

Individual Growth Models Of Change In Peabody Picture Vocabulary Scores Of Children Treated For Brain Tumors, Ying Shen

Mathematics Theses

The individual growth model is a relatively new statistical technique. It is now widely used to examine the trajectories of individuals and groups in repeated measures data. This study examines the association of the receptive vocabulary over time and characteristics of children who were treated for brain tumors. The children undertook different types of treatment from one to any combinations of surgery, radiation and chemotherapy. The individual growth model is used to analyze the longitudinal data and to address the issues behind the data. Results of this study present several factors' influences to the rate of change of PPVT scores. …


Intrinsic Absorption With The Far Ultraviolet Spectroscopic Explorer, Jay Patrick Dunn Nov 2007

Intrinsic Absorption With The Far Ultraviolet Spectroscopic Explorer, Jay Patrick Dunn

Physics and Astronomy Dissertations

We present a survey of 72 Seyfert galaxies and quasars observed by the Far Ultraviolet Spectroscopic Explorer (FUSE). Our survey is the largest to date searching for intrinsic UV absorption with high spectral resolution, and is the first step toward a more comprehensive study of intrinsic absorption in low-redshift AGN. We have determined that 72 of 253 available active galactic nuclei (AGN) are viable targets for detection of intrinsic absorption lines. We examined these spectra for signs of intrinsic absorption in the O VI doublet (lambda lamdba 1031.9, 1037.6) and Lyman beta (lambda 1025.7). The fraction of Seyfert 1 galaxies …


Electrokinetic Modeling Of Free Solution Electrophoresis, Yao Xin Nov 2007

Electrokinetic Modeling Of Free Solution Electrophoresis, Yao Xin

Chemistry Dissertations

Modeling electrophoresis of peptides, proteins, DNA, blood cells and colloids is based on classical electrokinetic theory. The coupled field equations-Poisson, Navier-Stokes or Brinkman, and ion transport equations are solved numerically to calculate the electrophoretic mobilities. First, free solution electrophoretic mobility expressions are derived for weakly charged rigid bead arrays. Variables include the number of beads (N), their size (radius), charge, distribution (configuration), salt type, and salt concentration. We apply these mobility expressions to rings, rigid rods, and wormlike chain models and then apply the approach to the electrophoretic mobilities and translational diffusion constants of weakly charged peptides. It is shown …


Exploring The Role Of Calcium Ions In Biological Systems By Computational Prediction And Protein Engineering, Yubin Zhou Nov 2007

Exploring The Role Of Calcium Ions In Biological Systems By Computational Prediction And Protein Engineering, Yubin Zhou

Chemistry Dissertations

Ca2+, a signal for death and life, is closely involved in the regulation of numerous important cellular events. Ca2+ carries out its function through its binding to Ca2+-receptors or Ca2+-binding proteins. The EF-hand protein, with a helix-loop-helix Ca2+-binding motif, constitutes one of the largest protein families. To facilitate our understanding of the role of Ca2+ in biological systems (denoted as calciomics) using genomic information, an improved pattern search method (http://www.chemistry.gsu.edu/faculty/Yang/Calciomics.htm) for the identification of EF-hand and EF-like Ca2+-binding proteins was developed. This fast and robust method allows us to analyze putative EF-hand proteins at the genome-wide level and further visualize …


Ieee 802.15.4 Mac Protocol Study And Improvement, Liang Cheng Nov 2007

Ieee 802.15.4 Mac Protocol Study And Improvement, Liang Cheng

Computer Science Dissertations

IEEE 802.15.4 is a standard used for low rate personal area networks (PANs). It offers device level connectivity in applications with limited ower and relaxed throughput requirements. Devices with IEEE 802.15.4 technology can be used in many potential applications, such as home networking, industry/environments monitoring, healthcare equipments, etc, due to its extremely low power features. Although the superframe beacons play the key role in synchronizing channel access in IEEE 802.15.4, they are sources for energy inefficiency. This research focuses on exploring how to optimize the beacons, and designing novel schemes to distribute the information that are supposed to be delivered …


Computational Intelligence Based Classifier Fusion Models For Biomedical Classification Applications, Xiujuan Chen Nov 2007

Computational Intelligence Based Classifier Fusion Models For Biomedical Classification Applications, Xiujuan Chen

Computer Science Dissertations

The generalization abilities of machine learning algorithms often depend on the algorithms’ initialization, parameter settings, training sets, or feature selections. For instance, SVM classifier performance largely relies on whether the selected kernel functions are suitable for real application data. To enhance the performance of individual classifiers, this dissertation proposes classifier fusion models using computational intelligence knowledge to combine different classifiers. The first fusion model called T1FFSVM combines multiple SVM classifiers through constructing a fuzzy logic system. T1FFSVM can be improved by tuning the fuzzy membership functions of linguistic variables using genetic algorithms. The improved model is called GFFSVM. To better …


A Contextualized Web-Based Learning Environments For Devs Models, Inthira Srivrunyoo Nov 2007

A Contextualized Web-Based Learning Environments For Devs Models, Inthira Srivrunyoo

Computer Science Theses

With the advance in applying technology in education, the traditional lecture-driven teaching style is gradually replaced by a more active teaching style where the students play a more active rule in the learning process. In this paper we introduce a new initiative to provide a suite of online tools for learning DEVS model. The uniqueness of this tutorial project is the integration of information technology and multimedia into education through the development of an interactive tutorial and the characteristic of contextualized learning. The tutorial teaches students about the basic aspects of discrete event system and simulation. The interactive tutorial fully …


Improving Feature Selection Techniques For Machine Learning, Feng Tan Nov 2007

Improving Feature Selection Techniques For Machine Learning, Feng Tan

Computer Science Dissertations

As a commonly used technique in data preprocessing for machine learning, feature selection identifies important features and removes irrelevant, redundant or noise features to reduce the dimensionality of feature space. It improves efficiency, accuracy and comprehensibility of the models built by learning algorithms. Feature selection techniques have been widely employed in a variety of applications, such as genomic analysis, information retrieval, and text categorization. Researchers have introduced many feature selection algorithms with different selection criteria. However, it has been discovered that no single criterion is best for all applications. We proposed a hybrid feature selection framework called based on genetic …


Prediction Of Oxidation States Of Cysteines And Disulphide Connectivity, Aiguo Du Nov 2007

Prediction Of Oxidation States Of Cysteines And Disulphide Connectivity, Aiguo Du

Computer Science Dissertations

Knowledge on cysteine oxidation state and disulfide bond connectivity is of great importance to protein chemistry and 3-D structures. This research is aimed at finding the most relevant features in prediction of cysteines oxidation states and the disulfide bonds connectivity of proteins. Models predicting the oxidation states of cysteines are developed with machine learning techniques such as Support Vector Machines (SVMs) and Associative Neural Networks (ASNNs). A record high prediction accuracy of oxidation state, 95%, is achieved by incorporating the oxidation states of N-terminus cysteines, flanking sequences of cysteines and global information on the protein chain (number of cysteines, length …


Genotype/Haplotype Tagging Methods And Their Validation, Jun Zhang Nov 2007

Genotype/Haplotype Tagging Methods And Their Validation, Jun Zhang

Computer Science Theses

This study focuses how the MLR-tagging for statistical covering, i.e. either maximizing average R2 for certain number of requested tags or minimizing number of tags such that for any non-tag SNP there exists a highly correlated (squared correlation R2 > 0.8) tag SNP. We compare with tagger, a software for selecting tags in hapMap project. MLR-tagging needs less number of tags than tagger in all 6 cases of the given test sets except 2. Meanwhile, Biologists can detect or collect data only from a small set. So, this will bring a problem for scientists that the estimates accuracy of tag SNPs …


Ammp-Extn: A User Privacy And Collaboration Control Framework For A Multi-User Collaboratory Virtual Reality System, Wenjun Ma Oct 2007

Ammp-Extn: A User Privacy And Collaboration Control Framework For A Multi-User Collaboratory Virtual Reality System, Wenjun Ma

Computer Science Theses

In this thesis, we propose a new design of privacy and session control for improving a collaborative molecular modeling CVR system AMMP-VIS [1]. The design mainly addresses the issue of competing user interests and privacy protection coordination. Based on our investigation of AMMP-VIS, we propose a four-level access control structure for collaborative sessions and dynamic action priority specification for manipulations on shared molecular models. Our design allows a single user to participate in multiple simultaneous sessions. Moreover, a messaging system with text chatting and system broadcasting functionality is included. A 2D user interface [2] for easy command invocation is developed …


On Inter-Referential Awareness In Collaborative Augmented Reality, Jeffrey William Chastine Aug 2007

On Inter-Referential Awareness In Collaborative Augmented Reality, Jeffrey William Chastine

Computer Science Dissertations

For successful collaboration to occur, a workspace must support inter-referential awareness - or the ability for one participant to refer to a set of artifacts in the environment, and for that reference to be correctly interpreted by others. While referring to objects in our everyday environment is a straight-forward task, the non-tangible nature of digital artifacts presents us with new interaction challenges. Augmented reality (AR) is inextricably linked to the physical world, and it is natural to believe that the re-integration of physical artifacts into the workspace makes referencing tasks easier; however, we find that these environments combine the referencing …


An Optimal Solution On Screening And Treatment Of Chlamydia Trachomatis And Neisseria Gonorrhoeae, Xin Wei Aug 2007

An Optimal Solution On Screening And Treatment Of Chlamydia Trachomatis And Neisseria Gonorrhoeae, Xin Wei

Mathematics Theses

We propose a resource allocation model for the management of the fund for the screening and treatment of women infected by Chlamydia trachomatis and Neisseria gonorrhoeae. The goal is to maximize the number of infected women cured of Chlamydia trachomatis and Neisseria gonorrhoeae infections. The population going for screening is divided into groups by ages and races. The group number is dynamic. Dierent groups have dierent infection rates. There are four possible test assays and four possible treatments. We employed a two-phase algorithm to solve the problem. The first phase is small so an exhaustive method is applied, while the …


Inspection And Characterization Of Exoplanet Using The Chara Array, Ellyn K. Baines Aug 2007

Inspection And Characterization Of Exoplanet Using The Chara Array, Ellyn K. Baines

Physics and Astronomy Dissertations

Until the last decade or so, our entire knowledge of planets around Sun-like stars consisted of those in our own Solar System. This is no longer the case. Over 200 planets have been discovered through radial velocity surveys and photometric studies, both of which depend on observing the planet's effects on its host star. Much of our knowledge of the planets orbiting these stars is uncertain, based on assumptions about the stars' masses and the planets' orbital inclinations. This dissertation is comprised of two main sections. The first involves measuring the angular diameters for a sample of exoplanet host stars …


Hot Stars With Disks, Erika Dawn Grundstrom Aug 2007

Hot Stars With Disks, Erika Dawn Grundstrom

Physics and Astronomy Dissertations

The evolutionary paths of the massive O and B type stars are often defined by angular momentum transformations that involve circumstellar gas disks. This circumstellar gas is revealed in several kinds of observations, and here I describe a series of investigations of the hydrogen line emission from such disk using detailed studies of five massive binaries and a survey of 128 Be stars. By examining three sets of spectra of the active mass-transfer binary system RY Scuti, I determined masses of 7.1 +/- 1.2 M_sun for the bright supergiant and 30.0 +/- 2.1 M_sun for the massive companion that is …


Dust Within The Central Regions Of Seyfert Galaxies, Rajesh Deo Aug 2007

Dust Within The Central Regions Of Seyfert Galaxies, Rajesh Deo

Physics and Astronomy Dissertations

We present a detailed study of mid-infrared spectroscopy and optical imaging of Seyfert galaxies with the goal of understanding the properties of astronomical dust around the central supermassive black hole and the accretion disk. Specifically, we have studied Spitzer Space Telescope mid-infrared spectra of 12 Seyfert 1.8-1.9s and 58 Seyfert 1s and 2s available in the Spitzer public archive, and the nuclear dust morphology in the central 500 pc of 91 narrow and broad-line Seyfert 1s using optical images from the Hubble Space Telescope. We have also developed visualization software to aid the understanding of the geometry of the central …


Identifying Calcium-Binding Sites And Predicting Disulfide Connectivity, Hai Deng Aug 2007

Identifying Calcium-Binding Sites And Predicting Disulfide Connectivity, Hai Deng

Computer Science Dissertations

Most questions in proteomics require complex answers. Yet graph theory, supervised learning, and statistical model have decomposed complex questions into simple questions with simple answers. The expertise in the field of protein study often address tasks that demand answers as complex as the questions. Such complex answers may consist of multiple factors that must be weighed against each other to arrive at a globally satisfactory and consistent solution to the question. In the prediction of calcium binding in proteins, we construct a global oxygen contact graph of a protein, then apply a graph algorithm to find oxygen clusters with the …


Study Of Factors Of Affecting Recurrence Of Myoma After Myomectomy, Lu Wang Aug 2007

Study Of Factors Of Affecting Recurrence Of Myoma After Myomectomy, Lu Wang

Mathematics Theses

This study is performed to evaluate the factors associated with the recurrence of myoma after Myomectomy. Identifying the factors of myoma recurrence will assist the patient and her gynecologist in deciding the most appropriate method of treatment according to her specific social, medical and emotional needs. Multiple logistic regression is used to determine the factors affecting the recurrence. 'Age of Surgery', 'Tumor Size', 'Pelvic Pain' and the interaction between the 'Age of Surgery' and 'Tumor Size' are significant in the final model. Kaplan-Meier method is used to calculate the cumulative recurrence rate. The 5 year cumulative recurrence rate is 24.32% …


Polynomial Functions Over Rings Of Residue Classes Of Integers, M Brandon Meredith Aug 2007

Polynomial Functions Over Rings Of Residue Classes Of Integers, M Brandon Meredith

Mathematics Theses

In this thesis we discuss how to find equivalent representations of polynomial functions over the ring of integers modulo a power of a prime. Specifically, we look for lower degree representations and representations with fewer variables for which important applications in electrical and computer engineering exist. We present several algorithms for finding these compact formulations.