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Full-Text Articles in Physical Sciences and Mathematics

The Viability Of Is Enhanced Knowledge Sharing In Mission-Critical Command And Control Centers, Sameh A. Sabet Aug 2006

The Viability Of Is Enhanced Knowledge Sharing In Mission-Critical Command And Control Centers, Sameh A. Sabet

Dissertations

Engineering processes such as the maintenance of mission-critical infrastructures are highly unpredictable processes that are vital for everyday life, as well as for national security goals. These processes are categorized as Emergent Knowledge Processes (EKP), organizational processes that are characterized by a changing set of actors, distributed knowledge bases, and emergent knowledge sharing activities where the process itself has no predetermined structure. The research described here utilizes the telecommunications network fault diagnosis process as a specific example of an EKP. The field site chosen for this research is a global undersea telecommunication network where nodes are staffed by trained personnel …


Selected Problems Of Inference On Branching Processes And Poisson Shock Model, Satrajit Roychoudhury Aug 2006

Selected Problems Of Inference On Branching Processes And Poisson Shock Model, Satrajit Roychoudhury

Dissertations

This dissertation explores the development of statistical methodology for some problems of branching processes and poisson shock model.

Branching process methods have become extremely popular in recent days. This dissertation mainly explores two fundamental inference problems of Galton-Watson processes. The first problem is concerned with statistical inference regarding the nature of the process. Two methodologies have been developed to develop a statistical test for the null hypothesis that the process is supercritical versus an alternative hypothesis that the process is non-supercritical. Another problem we investigate involves the estimation of the 'age' of a Galton-Watson Process. Three different methods are discussed …


Feasibility Of Superconductivity In Semiconductor Superlatices, Kenneth P. Walsh Aug 2006

Feasibility Of Superconductivity In Semiconductor Superlatices, Kenneth P. Walsh

Dissertations

The objective of this thesis is to explore superconductivity in semiconductor superlattices of alternating hole and electron layers. The feasibility of superconductivity in semiconductor superlattices is based on a model formulated by Harshrnan and Mills. In this model, a semiconductor superlattice forms the layered electron and hole reservoirs of high transition temperature (high-Tc) superconductors.

A GaAs-A1xGa1-xAs semiconductor structure is proposed which is predicted to superconduct at Tc = 2.0 K and may be analogous to the layered electronic structure of high-Tc superconductors. Formation of an alternating sequence of electron- and hole-populated quantum wells (an electron-hole superlattice) in a modulation-doped GaAs- …


Earthshine : Photometry, Modeling, And Spectral Observations, Jeffrey Patrick Hickey Aug 2006

Earthshine : Photometry, Modeling, And Spectral Observations, Jeffrey Patrick Hickey

Theses

The Earthshine group has been making sustained observations of the Earthshine from Big Bear Solar Observatory in California since late 1998. There have also been intermittent observations from 1994-5. High and low resolution Earthshine spectral observations have also been under taken at Palomar Observatory since 1999. The group has re-invigorated and modernized a nearly forgotten way of measuring the Earth's albedo, and hence its energy balance, previously studied by Danjon (and his followers) for about twenty-five years early in the last century, using their observations of the Earthshine from France. This is an overview paper covering observations, reductions, simulations, and …


Study Of Propagation And Detection Methods Of Terahertz Radiation For Spectroscopy And Imaging, Aparajita Bandyopadhyay May 2006

Study Of Propagation And Detection Methods Of Terahertz Radiation For Spectroscopy And Imaging, Aparajita Bandyopadhyay

Dissertations

The applications of terahertz (THz, 1 THz is 1012 cycles per second or 300 pm in wavelength) radiation are rapidly expanding. In particular, THz imaging is emerging as a powerful technique to spatially map a wide variety of objects with spectral features which are present for many materials in THz region. Objects buried within dielectric structures can also be imaged due to the transparency of most dielectrics in this regime. Unfortunately, the image quality in such applications is inherently influenced by the scattering introduced by the sample inhomogeneities and by the presence of barriers that reduces both the transmitted power …


Linear And Log-Linear Models Based On Generalized Inverse Sampling Scheme, Soumi Lahiri May 2006

Linear And Log-Linear Models Based On Generalized Inverse Sampling Scheme, Soumi Lahiri

Dissertations

This dissertation explores the development of novel statistical techniques and the applications in modeling rare events using generalized inverse sampling scheme. The Poisson model can be used for independent frequency count data. Also negative binomial and negative multinomial (NMn) models are applicable when there is only one rare category in the population. Here, a new model, based on generalized inverse sampling scheme, is introduced to study several rare events simultaneouly. The generalized inverse sampling scheme is used to study several rare categories of a population. Samples are drawn until a predetermined number of the total of the rare events occur. …


Novel Characterization Of Materials Using Thz Spectroscopic Techniques, Amartya Sengupta May 2006

Novel Characterization Of Materials Using Thz Spectroscopic Techniques, Amartya Sengupta

Dissertations

Significant scientific and technical challenges within the terahertz (THz) frequency regime have recently motivated an array of new research activities. This involves numerous applications of this region of the electromagnetic spectrum between approximately 100 GHz (3mm) and 3 THz (100 µm) for both spectroscopy and imaging purposes. THz time domain spectroscopy is unique in that the time domain waveforms are measured and the complex optical constants are deduced directly without resorting to the Kramers-Kronig Analysis.

In this work, THz spectroscopy has been used to characterize different types of materials. Materials investigated consisted of semiconductors, gate dielectric materials, high energetic materials …


Mathematical Problems Arising In Interfacial Electrohydrodynamics, Dmitri Tseluiko May 2006

Mathematical Problems Arising In Interfacial Electrohydrodynamics, Dmitri Tseluiko

Dissertations

In this work we consider the nonlinear stability of thin films in the presence of electric fields. We study a perfectly conducting thin film flow down an inclined plane in the presence of an electric field which is uniform in its undisturbed state, and normal to the plate at infinity. In addition, the effect of normal electric fields on films lying above, or hanging from, horizontal substrates is considered. Systematic asymptotic expansions are used to derive fully nonlinear long wave model equations for the scaled interface motion and corresponding flow fields. For the case of an inclined plane, higher order …


Facial Analysis In Video : Detection And Recognition, Peichung Shih May 2006

Facial Analysis In Video : Detection And Recognition, Peichung Shih

Dissertations

Biometric authentication systems automatically identify or verify individuals using physiological (e.g., face, fingerprint, hand geometry, retina scan) or behavioral (e.g., speaking pattern, signature, keystroke dynamics) characteristics. Among these biometrics, facial patterns have the major advantage of being the least intrusive. Automatic face recognition systems thus have great potential in a wide spectrum of application areas. Focusing on facial analysis, this dissertation presents a face detection method and numerous feature extraction methods for face recognition.

Concerning face detection, a video-based frontal face detection method has been developed using motion analysis and color information to derive field of interests, and distribution-based distance …


Interactions Of Ionic Liquids With Uranium And Its Implications On Biotransformation, Chengdong Zhang May 2006

Interactions Of Ionic Liquids With Uranium And Its Implications On Biotransformation, Chengdong Zhang

Dissertations

Room temperature ionic liquids (ILs) are pure ionic compounds with melting points below 100°C, which have drawn great attention due to their many unique properties. They have been widely used in organic synthesis, analytical chemistry, and biochemistry. Although ionic liquids have been used to extract metals and radionuclides, there is no systematic study on the interactions of ILs with uranium and their effects on the biotransformation of uranium.

My research focused on: (1) the interactions between uranium and ionic liquids in aqueous solution; and (2) biotransformation of uranium in the presence of ILs. The interactions between three representative ionic liquids, …


Enhancing Web Marketing By Using Ontology, Xuan Zhou May 2006

Enhancing Web Marketing By Using Ontology, Xuan Zhou

Dissertations

The existence of the Web has a major impact on people's life styles. Online shopping, online banking, email, instant messenger services, search engines and bulletin boards have gradually become parts of our daily life. All kinds of information can be found on the Web. Web marketing is one of the ways to make use of online information. By extracting demographic information and interest information from the Web, marketing knowledge can be augmented by applying data mining algorithms. Therefore, this knowledge which connects customers to products can be used for marketing purposes and for targeting existing and potential customers. The Web …


Structural Auditing Methodologies For Controlled Terminologies, Hua Min May 2006

Structural Auditing Methodologies For Controlled Terminologies, Hua Min

Dissertations

Several auditing methodologies for large controlled terminologies are developed. These are applied to the Unified Medical Language System XXXX and the National Cancer Institute Thesaurus (NCIT). Structural auditing methodologies are based on the structural aspects such as IS-A hierarchy relationships groups of concepts assigned to semantic types and groups of relationships defined for concepts. Structurally uniform groups of concepts tend to be semantically uniform. Structural auditing methodologies focus on concepts with unlikely or rare configuration. These concepts have a high likelihood for errors.

One of the methodologies is based on comparing hierarchical relationships between the META and SN, two major …


Gas Chromatography On Self Assembled Single Walled Carbon Nanotubes, Mahesh Kumar Karwa May 2006

Gas Chromatography On Self Assembled Single Walled Carbon Nanotubes, Mahesh Kumar Karwa

Dissertations

Carbon nanotubes (CNTs) are nano-sized carbon-based sorbents, which have high surface area, large aspect ratio, can be self-assembled and are known to be stable at high temperatures. It is therefore conceivable that separation techniques, such as, gas chromatography (GC) can benefit from their unique properties and nano-scale interactions. Self-assembly, in-contrast to packing these materials in a tube, prevents them from agglomeration and thus facilitates in retaining their nano-characteristics. In this research, novel substrates, such as, steel tubings, on a scaled-up level have been explored for the self-assembly process of CNTs, for applications such as gas chromatography, where the CNTs served …


Environmental Policy In Jordan : Analysis, Gap Identification, And Strategies For Improvement, Diana Saed May 2006

Environmental Policy In Jordan : Analysis, Gap Identification, And Strategies For Improvement, Diana Saed

Theses

Jordan is a country with a tremendously fragile environment. It faces substantial environmental challenges due to its delicate environmental resources and its limited financial assets. These challenges are aggravated by the scarcity of available water, deterioration of the water resources, land contamination, desertification, mismanagement of land use, and air pollution. Attempting to describe the “State of the Environment” and to provide an informed analysis of the threats to the nation’s environment is a Herculean task. This analysis examines the efforts made by Jordan in regard to protection and management of the environment. This thesis provides a snapshot of the major …


A Data Gathering Toolkit For Biological Information Integration, Munira Lokhandwala May 2006

A Data Gathering Toolkit For Biological Information Integration, Munira Lokhandwala

Theses

SYSTERS is a biological information integration system containing protein sequences from many protein databases such as Swiss-Prot and TrEMBL and also protein sequences from complete genomes available at Ensembl, The Arabidopsis Information Resource, SGD and GeneDB. For some protein sequences their encoding nucleotide sequences can be found in their corresponding websites. However, for some protein sequences their encoding nucleotide sequences are missing.

The goal of this thesis is to. collect all nucleotide sequences for the protein sequences in SYSTERS and store them in a common database. There are two cases. The first case is that if the nucleotide sequences can …


Separation Of Ssl Protocol Phases Across Process Boundaries, Kirthikar Anantharam May 2006

Separation Of Ssl Protocol Phases Across Process Boundaries, Kirthikar Anantharam

Theses

Secure Sockets Layer is the de-facto standard used in the industry today for secure communications through web sites. An SSL connection is established by performing a Handshake, which is followed by the Record phase. While the SSL Handshake is computationally intensive and can cause of bottlenecks on an application server, the Record phase can cause similar bottlenecks while encrypting large volumes of data.

SSL Accelerators have been used to improve the performance of SSL-based application servers. These devices are expensive, complex to configure and inflexible to customizations. By separating the SSL Handshake and the Record phases into separate software processes, …


Network Activity Arising From Optimal Diameters Of Neuronal Processes, Juliane Gansert May 2006

Network Activity Arising From Optimal Diameters Of Neuronal Processes, Juliane Gansert

Theses

Electrical coupling provides an important pathway for signal transmission between neurons. In several regions of the mammalian brain electrical synapses have been detected, and their role in the synchronization of neural networks and the generation of oscillations has been studied theoretically. Recently, it has been found that the amplitude of the postsynaptic potential is maximized for a specific diameter of the postsynaptic fiber.

In this thesis, the impact of the fiber's diameter on the success or failure of the action potential initiation and propagation is studied theoretically. Systems of two coupled neurons, as well as small networks, are investigated. The …


Comparative Analysis Of Parametric, Nonparametric And Permutation Methods For Differential Expression, Rahul Patil May 2006

Comparative Analysis Of Parametric, Nonparametric And Permutation Methods For Differential Expression, Rahul Patil

Theses

DNA microarrays permit us to study the expression of thousands of genes simultaneously. They are now used in many different contexts to compare mRNA levels between two or more samples of cells. Microarray experiments typically give us expression measurements on a large number of genes. Increasing popularity of microarray technology has resulted in a number of tests being proposed to detect differentials expression.

The purpose of study is to compare the parametric, non parametric and permutation tests when applied to microarray data for differential expression analysis. t test (parametric), Mann Whitney test (nonparametric) and Significance of analysis (permutation ) test …


The Effects Of Limited Rebuild Buffer And Track Buffers On Rebuild Time In Raid5, Chintan Shah May 2006

The Effects Of Limited Rebuild Buffer And Track Buffers On Rebuild Time In Raid5, Chintan Shah

Theses

Redundant Arrays of Independent Disks (RAID) are very popular for creating large, reliable storage systems. A RAID array consists of multiple independent disks that achieve fault tolerance by parity coding. The contents on a failed disk can be reconstructed on demand by reading and exciusive-ORing the corresponding blocks on surviving disks. Upon disk failure, the array enters rebuild mode when it begins to systematically reconstruct the data of the failed disk on a spare disk, provided one is available. The fundamental element of rebuild is the Rebuild Unit (RU).

Surviving disks engaged in rebuild, process user requests at a higher …


Dynamic Recomposition Of Documents From Distributed Data Sources, Abhishek Verma May 2006

Dynamic Recomposition Of Documents From Distributed Data Sources, Abhishek Verma

Theses

Dynamic recomposition of documents refers to the process of on-the-fly creation of documents. A document can be generated from several documents that are stored at distributed data sites. The source can be queried and results obtained in the form of XML. These XML documents can be combined after a series of transformation operations to obtain the target document. The resultant document can be stored statically or in the form of a command, which can be invoked later to recompose this document dynamically. Also, in case a change is made to a document, then only the change can be stored, instead …


Smart Home Technology For Aging, Fareedh Meeran May 2006

Smart Home Technology For Aging, Fareedh Meeran

Theses

The majority of the growing population, in the US and the rest of the world requires some degree of formal and or informal care either due to the loss of function or failing health as a result of aging and most of them suffer from chronic disorders. The cost and burden of caring for elders is steadily increasing. This thesis focuses on providing the analysis of the technologies with which a Smart Home is built to improve the quality of life of the elderly. A great deal of emphasis is given to the sensor technologies that are the back bone …


Finding Role Errors Of The Ncit Gene Hierarchy Using The Ncbi, Marc Oren May 2006

Finding Role Errors Of The Ncit Gene Hierarchy Using The Ncbi, Marc Oren

Theses

Due to the knowledge discovery process of gene information, details such as organism and chromosomal location should be known. Furthermore, the extensive biomedical research in genomics led to discovery of processes and diseases in which a gene plays a role. In the Gene hierarchy of the NCI Thesaurus (NCIT) such knowledge is represented by appropriate roles. However, upon review of the Gene hierarchy of the NCIT, many role errors are found. Realizing that such details are provided by another knowledge repository of NIH, the NCBI gene database, a methodology is presented to use NCBI to discover role errors for the …


Text Mining With Exploitation Of User's Background Knowledge : Discovering Novel Association Rules From Text, Xin Chen Jan 2006

Text Mining With Exploitation Of User's Background Knowledge : Discovering Novel Association Rules From Text, Xin Chen

Dissertations

The goal of text mining is to find interesting and non-trivial patterns or knowledge from unstructured documents. Both objective and subjective measures have been proposed in the literature to evaluate the interestingness of discovered patterns. However, objective measures alone are insufficient because such measures do not consider knowledge and interests of the users. Subjective measures require explicit input of user expectations which is difficult or even impossible to obtain in text mining environments.

This study proposes a user-oriented text-mining framework and applies it to the problem of discovering novel association rules from documents. The developed system, uMining, consists of two …


Facial Feature Representation And Recognition, Chao-Fa Chuang Jan 2006

Facial Feature Representation And Recognition, Chao-Fa Chuang

Dissertations

Facial expression provides an important behavioral measure for studies of emotion, cognitive processes, and social interaction. Facial expression representation and recognition have become a promising research area during recent years. Its applications include human-computer interfaces, human emotion analysis, and medical care and cure.

In this dissertation, the fundamental techniques will be first reviewed, and the developments of the novel algorithms and theorems will be presented later. The objective of the proposed algorithm is to provide a reliable, fast, and integrated procedure to recognize either seven prototypical, emotion-specified expressions (e.g., happy, neutral, angry, disgust, fear, sad, and surprise in JAFFE database) …


Color Image Quality Measures And Retrieval, Yan-Yu Fu Jan 2006

Color Image Quality Measures And Retrieval, Yan-Yu Fu

Dissertations

The focus of this dissertation is mainly on color image, especially on the images with lossy compression. Issues related to color quantization, color correction, color image retrieval and color image quality evaluation are addressed. A no-reference color image quality index is proposed. A novel color correction method applied to low bit-rate JPEG image is developed. A novel method for content-based image retrieval based upon combined feature vectors of shape, texture, and color similarities has been suggested. In addition, an image specific color reduction method has been introduced, which allows a 24-bit JPEG image to be shown in the 8-bit color …


Ligand-Based Design Of Dopamine Reuptake Inhibitors : Fuzzy Relational Clustering And 2-D And 3-D Qsar Modleing, Milind Misra Jan 2006

Ligand-Based Design Of Dopamine Reuptake Inhibitors : Fuzzy Relational Clustering And 2-D And 3-D Qsar Modleing, Milind Misra

Dissertations

As the three-dimensional structure of the dopamine transporter (DAT) remains undiscovered, any attempt to model the binding of drug-like ligands to this protein must necessarily include strategies that use ligand information. For flexible ligands that bind to the DAT, the identification of the binding conformation becomes an important but challenging task. In the first part of this work, the selection of a few representative structures as putative binding conformations from a large collection of conformations of a flexible GBR 12909 analogue was demonstrated by cluster analysis. Novel structurebased features that can be easily generalized to other molecules were developed and …


Dynamic Measuring Tools For Online Discourse, Jeffrey S. Saltz Jan 2006

Dynamic Measuring Tools For Online Discourse, Jeffrey S. Saltz

Dissertations

When evaluating participation within an Asynchronous Learning Network (ALN), current best practices include counting messages and reviewing participant surveys. To understand the impact of more advanced dynamic measurement tools for use within an ALN, a web-based tool, known as iPET (the integrated Participation Evaluation Tool), was created. iPET, which leverages Social Network Analysis and Information Visualization techniques, was then evaluated via an empirical study. This research demonstrates that using a tool such as iPET increases participation within an ALN without increasing facilitator workload. Due to the fact that active online discussion is a key factor in the success of an …


Study Of Organic Reactions In Pyridinium-Based Ionic Liquids, Ying Xiao Jan 2006

Study Of Organic Reactions In Pyridinium-Based Ionic Liquids, Ying Xiao

Dissertations

Recently, ionic liquids have attracted a lot of attention as novel materials for organic transformations. This is due to their unique properties, which make them suitable substitutes for organic solvents. Most of the available literature is focused on the application of imidazolium-based ionic liquids for organic reactions, while very limited information is available on the application of pyridinium-based ionic liquids.

In this study, two different ionic liquids, 1 -ethyl-pyridinium tetrafluoroborate ([EtPy]+[BF4]-) and 1 -ethyl-pyridinium trifluoroacetate ([EtPy]+[CF3COO]-) have been investigated. Compared to previous reports, the synthetic technique for preparation …


Quantifying Software Architecture Attributes, Bo Yu Jan 2006

Quantifying Software Architecture Attributes, Bo Yu

Dissertations

Software architecture holds the promise of advancing the state of the art in software engineering. The architecture is emerging as the focal point of many modem reuse/evolutionary paradigms, such as Product Line Engineering, Component Based Software Engineering, and COTS-based software development.

The author focuses his research work on characterizing some properties of a software architecture. He tries to use software metrics to represent the error propagation probabilities, change propagation probabilities, and requirements change propagation probabilities of a software architecture. Error propagation probability reflects the probability that an error that arises in one component of the architecture will propagate to other …


Development Of Environmentally Benign Microencapsulation With Polymer Microspheres And Liposomes, Baohua Yue Jan 2006

Development Of Environmentally Benign Microencapsulation With Polymer Microspheres And Liposomes, Baohua Yue

Dissertations

Microencapsulation means applying a shell-like coating to encapsulate the contents of interest in a particle form with a size range of few micrometers or below. In this work, aqueous liposome systems and polymer based encapsulation of fine particles in supercritical CO2 were studied. Compared to many other microencapsulation methods, these two methodologies feature reduction/prevention of using organic solvents, making them particularly attractive as green technology.

For polymer microencapsulation, a novel in situ polymerization based process to encapsulate various types of fine particles, include drugs, fire retardant, inorganic nanoparticles, and carbon nanotubes, was developed. In the process, host particles, monomers …