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Full-Text Articles in Physical Sciences and Mathematics

Discrete Mathematics With Proof Second Edition, Eric Gossett Jan 2009

Discrete Mathematics With Proof Second Edition, Eric Gossett

Faculty Books

Discrete mathematics has become increasingly popular in recent years due to its growing applications in the field of computer science. Discrete Mathematics with Proof, Second Edition continues to facilitate an up-to-date understanding of this important topic, exposing readers to a wide range of modern and technological applications. The book begins with an introductory chapter that provides an accessible explanation of discrete mathematics. Subsequent chapters explore additional related topics including counting, finite probability theory, recursion, formal models in computer science, graph theory, trees, the concepts of functions, and relations.

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A Privacy Enhanced Situation-Aware Middleware Framework For Ubiquitous Computing Environments, Gautham V. Pallapa Jan 2009

A Privacy Enhanced Situation-Aware Middleware Framework For Ubiquitous Computing Environments, Gautham V. Pallapa

Computer Science and Engineering Dissertations - Archive

The Ubiquitous Computing paradigm integrates myriads of small, inexpensive, heterogeneous networked devices, including sensors, distributed throughout the environment, with the intent of enabling context awareness in systems deployed to monitor the environment. This is accomplished by monitoring events, such as access, or utilization of resources, and obtaining knowledge about user activities, and interactions with other entities in the environment. Existing context-aware systems predominantly encapsulate the occurred activities either by using Event-Condition-Action rules, where an instance of the event performs as a trigger, or by prediction mechanisms, such as Dynamic Bayesian Networks, which compute decisions, based on the information obtained. However, …

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Attributes Selection And Package Design To Maximize Visibility Of Objects, Md Zahiduzzaman Miah Jan 2009

Attributes Selection And Package Design To Maximize Visibility Of Objects, Md Zahiduzzaman Miah

Computer Science and Engineering Dissertations - Archive

In recent years, there has been significant interest in the development of ranking functions and efficient top-k retrieval algorithms to help users in ad-hoc search and retrieval in databases (e.g., buyers searching for products in a catalog). We introduce a complementary problem: how to guide a seller in selecting the best attributes of a new tuple (e.g., a new product) to highlight so that it stands out in the crowd of existing competitive products and is widely visible to the pool of potential buyers. For example, assume one wants to sell an iPod in e-commerce site, but the title allows …

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A Study Of Ejection Times Of Terrestrial Planets From The Habitable Zones Of The Solar Twins Hd 20782 And Hd 188015, Katherine Elizabeth Yeager Jan 2009

A Study Of Ejection Times Of Terrestrial Planets From The Habitable Zones Of The Solar Twins Hd 20782 And Hd 188015, Katherine Elizabeth Yeager

Physics Theses - Archive

We provide a detailed statistical study of the ejection of Earth-mass planets from the habitable zones of the solar twins HD 20782 and HD 188015. These systems possess a giant planet that crosses into the stellar habitable zone, thus effectively thwarting the possibility of habitable Earth-mass planets. In the case of HD 188015, the orbit of the giant planet is essentially circular, whereas in the case of HD 20782, it is extremely elliptical. As starting positions for the giant planets, we consider both the apogee and perigee position, whereas the starting positions of the Earth-mass planets are widely varied. For …

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Analysis Of Calorimeter/Itc Cosmic Ray Data From The Atlas Detector, And Preparation For Supersymmetry Searches, Carlos Francisco Medina Hernandez Jan 2009

Analysis Of Calorimeter/Itc Cosmic Ray Data From The Atlas Detector, And Preparation For Supersymmetry Searches, Carlos Francisco Medina Hernandez

Physics Theses - Archive

The Large Hadron Collider is the largest most ambitious experiment in high energy physics history. It involves the greatest number of scientists from around the world. The first collisions will start being produced in late 2009 and we expect that the information collected will help us understand the physics behind the standard model such as higgs physics and the supersymmetric theories. The Department of Physics at University of Texas at Arlington, and more specifically the high energy physics group is actively involved with the design, construction and commissioning process of the ATLAS Tile Calorimeter. The group is also participating in …

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Mixed Lineage Leukemia Histone Methylases In Gene Expresion And Cancer, Bibhu Prasad Mishra Jan 2009

Mixed Lineage Leukemia Histone Methylases In Gene Expresion And Cancer, Bibhu Prasad Mishra

Chemistry & Biochemistry Dissertations - Archive

Histone methyl-transferases (HMTs) are key enzymes that post-translationally methylate nuclear histone proteins and play critical roles in gene expression, epigenetic regulation and diseases in eukaryotic organisms. Mixed lineage leukemias (MLLs) are human HMTs that specifically methylate histone H3 at lyisine-4 and regulate gene activation. MLLs are also well known to undergo rearrangement often in acute myeloid and lymphoid leukemias. Human encodes several histone H3 lysine-4 (H3K4) specific methyl-transferases (HMTs) such as MLL1 (mixed lineage leukemia gene 1), MLL2, MLL3, hSet1 etc, which play critical roles in gene expression. These HMTs are present as distinct multi-protein complexes with several proteins in …

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Design And Synthesis Of A High Potential Ruthenium (Ii) Tetraazatetrapyridopentaphene Complex Capable Of Two-Electron Reduction, Nancy Ruth G. Diaz Jan 2009

Design And Synthesis Of A High Potential Ruthenium (Ii) Tetraazatetrapyridopentaphene Complex Capable Of Two-Electron Reduction, Nancy Ruth G. Diaz

Chemistry & Biochemistry Theses - Archive

We report the synthesis of a complex, [(phen)₂Ru(tatpph)Ru(phen)₂]⁴⁺ (Ph⁴⁺), which like its predecessor compound, [(phen)₂Ru(tatppc)Ru(phen)₂]⁴⁺ (Pc ⁴⁺), can undergo two sequential 1-electron photoreductions in MeCN in the presence of a sacrificial reductant. The initial complex, Ph ⁴⁺, can be completely regenerated from the singly and doubly reduced forms by exposure to air, although the rate of regeneration for the second photoreduction is much slower than the first. Electrochemical studies have shown that this complex is not only capable of storing multiple reducing equivalents but these equivalents have stored potentials that are significantly higher than the complex Pc ⁴⁺ and are …

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On The Sensitivity Of Ocean Circulation To Arctic Freshwater Pulses During The Paleocene/Eocene Thermal Maximum, Jesse Tiner Cope Jan 2009

On The Sensitivity Of Ocean Circulation To Arctic Freshwater Pulses During The Paleocene/Eocene Thermal Maximum, Jesse Tiner Cope

Earth & Environmental Sciences Theses - Archive

The Paleocene/Eocene Thermal Maximum (PETM) corresponds to a period characterized by extreme global warming caused by a massive carbon input into the ocean and atmosphere. Approximately 55 Ma in the early Cenozoic, evidence suggests an ice-free Arctic exchanged relatively fresh water with the remainder of the global ocean. In this study we use the Community Climate Systems Model version 3 (CCSM-3), including a carbon cycle model, to examine the sensitivity of deep-water formation and circulation within the global ocean to freshwater exchange from the Arctic Ocean during the PETM. Past modeling experiments show how alterations to seaway exchanges can have …

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Seismic Inversion In Fluvial Reservoirs: Building A Geologic Model-Based Inversion For The Stratton Field 3d Survey, Richard Charles Odom Jan 2009

Seismic Inversion In Fluvial Reservoirs: Building A Geologic Model-Based Inversion For The Stratton Field 3d Survey, Richard Charles Odom

Earth & Environmental Sciences Theses - Archive

Seismic surveys, in particular 3-D surveys, are an important tool for imaging geologic structure in the subsurface; they are routinely applied to map structural trends and geometry to define the reservoir structure. Many of the world's oil and gas reservoirs are sands deposited by river systems but the scales of fluvial architectural elements challenge the resolution of the seismic method. One such challenging field is the Stratton field in the FR-4 Gas Play of south Texas; the reservoir is Frio formation, a thick collection (greater than 3000 feet) of stacked fluvial deposits consisting of thin channels and splays of reservoir …

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High-Order Numerical Schemes For High-Speed Flows, Maria Luisa Bambozzi Oliveira Jan 2009

High-Order Numerical Schemes For High-Speed Flows, Maria Luisa Bambozzi Oliveira

Mathematics Dissertations - Archive

A numerical scheme with high order of accuracy is necessary to resolve small length scales in flow transition and turbulence processes. However, numerical simulation for shock-boundary layer interaction, shock-acoustic interaction, porous media flow and multiple phase flow, among others, also require a numerical scheme that can successfully capture discontinuities. To accomplish this, it is essential that an effective shock/discontinuity detector is implemented to reduce damping of physically important high-frequency waves.In this work, two high-order shock capturing schemes - the Weighted Essentially Non-Oscillatory (WENO) scheme and the Weighted Compact Scheme (WCS) - are investigated. Based on this analysis, a shock/discontinuity detector …

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Energy Efficient Routing Structures And Wakeup Schemes For Wireless Sensor Networks, Byoung Lee Jan 2009

Energy Efficient Routing Structures And Wakeup Schemes For Wireless Sensor Networks, Byoung Lee

Computer Science and Engineering Dissertations - Archive

Wireless sensor networks, which consist of a large number of sensor nodes and a base station, are used for many applications aimed at collecting information. Each sensor node is equipped with a small amount of battery, limited memory, finite radio range and small CPU. It gathers required information and it sends the information to the base station. The large number of sensors can cover a large area by cooperating with each other to build a multi-hop wireless network. However, the small amount of battery is one of the critical concerns because sensor network life time depends on battery longevity. It …

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A Simple Sn2 Reaction For The Undergraduate Organic Laboratory, John J. Esteb Jan 2009

A Simple Sn2 Reaction For The Undergraduate Organic Laboratory, John J. Esteb

Scholarship and Professional Work - LAS

A simple procedure for the synthesis of n-butyl naphthyl ether is presented. This procedure represents an easy method for the production of an aryl ether by an SN2 reaction, uses ethanol as an environmentally friendly solvent, and does not require the use of a lachrymator. Product isolation is done by pouring the reaction mixture over ice and collecting the solid by suction filtration. Students typically recover from 7–95% of the ether.

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A Flexible Solvolysis Experiment For The Undergraduate Organic Laboratory, John J. Esteb, John R. Magers, Luanne M. Mcnulty, Paul Morgan Jan 2009

A Flexible Solvolysis Experiment For The Undergraduate Organic Laboratory, John J. Esteb, John R. Magers, Luanne M. Mcnulty, Paul Morgan

Scholarship and Professional Work - LAS

A simple SN1 reaction is presented that uses bromotriphenylmethane and a range of oxygen-based nucleophiles including water and various alcohols. This procedure represents a process that affords easy isolation of solid products. Typical student yields ranged from 17–128% with the average yield of 50%. Students obtained products with a melting point range of 140 to 164 °C. This procedure offers multiple ways to adapt this experiment from a straight solvolysis reaction to a discovery-based experiment that explores the effect of nucleophile (for a more advanced group) or the method of product isolation.

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Multiple Linear Regression Model Of Visceral Leishmaniasis In Bihar, India, Darren Sheets Jan 2009

Multiple Linear Regression Model Of Visceral Leishmaniasis In Bihar, India, Darren Sheets

Mathematics Theses - Archive

Visceral Leishmaniasis (VL) is one of the world's worst parasitic killers, second only to Malaria, claiming nearly 500,000 lives each year. The disease attacks the spleen, liver, and bone marrow, and if left untreated is nearly always fatal. Whilst the disease is found all around the world, it is primarily prevalent in developing countries, in particular India. The most affected state in India is Bihar, where the disease is endemic. While other research has been conducted with emphasis on the effect of climate variables on the disease incidence rate, this analysis focuses on socio-economic variables such as literacy rate, housing …

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Enabling Context-Aware Applications In Smart Environments‏, Roman Arora Jan 2009

Enabling Context-Aware Applications In Smart Environments‏, Roman Arora

Computer Science and Engineering Theses - Archive

Recognizing human activities is an important feature for the development of contextaware applications that are so fundamental to enabling assistive environments. Only once these applications are able to determine the activities that their inhabitants are performing can they assist the individuals and their special needs. In order to do this, it is necessary to build models that can accurately capture and recognize the observed patterns. Equally important is the need to manage and distribute the information that has been inferred, and to provide Quality of Service (QoS) guarantees so that context-aware applications can react effectively to emergent situations. In this …

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Query Auditing Against Partial Disclosure, Mayur Motgi Jan 2009

Query Auditing Against Partial Disclosure, Mayur Motgi

Computer Science and Engineering Theses - Archive

Many government agencies, businesses, and nonprofit organizations need to collect, analyze, and report data about individuals in order to support their short-term and long-term planning activities. Statistical Databases therefore contain confidential information such as income, credit ratings, type of disease, or test scores of individuals. Such data are typically stored online and analyzed using sophisticated database management systems (DBMS) and software packages. On one hand, such database systems are expected to satisfy user requests of aggregate statistics related to non-confidential and confidential attributes. On the other hand, the system should be secure enough to guard against a user's ability to …

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Peon: Privacy-Enhanced Opportunistic Networks With Applications In Assistive Environments, Gauri Vakde Jan 2009

Peon: Privacy-Enhanced Opportunistic Networks With Applications In Assistive Environments, Gauri Vakde

Computer Science and Engineering Theses - Archive

Opportunistic Networking holds a great deal of potential for making communications easier and more flexible in pervasive assistive environments. However, security and privacy must be addressed to make these communications acceptable with respect to protecting patient privacy. We propose Privacy-Enhanced Opportunistic Networking (PEON), a system for using opportunistic networking in privacy-preserving way. PEON uses concepts from anonymous communications, re-routing messages through groups of peer nodes to hide the relation between the sources and destinations. We describe a set of protocols that explore a practical range of trade-offs between privacy and communication costs by modifying how closely the protocol adheres to …

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Web Application Integration Using Mashups, Ronda Hilton Jan 2009

Web Application Integration Using Mashups, Ronda Hilton

Computer Science and Engineering Theses - Archive

The HTML DOM is the W3C standard data model for HTML documents. A web page may be viewed as a tree structure with data nodes at each level, according to the HTML DOM, to enable web applications to access it dynamically. If a web page mashes up more than one web application, the data from one web application may flow as input into another. The user may manually transfer such data piecemeal by using the mouse to cut and paste the displayed text. Instead of this tedious and error-prone repetitious method of data transfer, the mashup may contain a software …

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Pseudo-Hierarchical Ant-Based Clustering Using A Heterogeneous Agent Hierarchy And Automatic Boundary Formation, Jeremy Bernard Brown Jan 2009

Pseudo-Hierarchical Ant-Based Clustering Using A Heterogeneous Agent Hierarchy And Automatic Boundary Formation, Jeremy Bernard Brown

Computer Science and Engineering Theses - Archive

The behavior and self-organization of ant colonies has been widely studied and served as the inspiration and source of many swarm intelligence models and related clustering algorithms. Unfortunately, most models that directly mimic ants produce too many clusters and converge too slowly. A wide range of research has attempted to address this issue through various means, but a number of problems remain: 1) Ants must still physically move from one cluster to another through intermediate locations, 2) current methods for remote relocation of an item only consider one movement at time to a particular location and do not consider patterns …

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An Auction Mechanism For Grid Scheduling And Resource Allocation In The Context Of Atlas, Tengkok Aaron Thor Jan 2009

An Auction Mechanism For Grid Scheduling And Resource Allocation In The Context Of Atlas, Tengkok Aaron Thor

Computer Science and Engineering Dissertations - Archive

The technological advancements in the areas of computing and networking over the recent years have led to an emerging infrastructure known as Computational Grids, which provides users with the flexibility of pervasive access to enormous computational resources hosted at remote locations. Effective resource management and job scheduling poses a challenge when constraints such as resource utilization, response time, global and local policies need to be taken into account, while dealing with potentially independent sources of jobs, computational, and storage resources. It must be ensured that scheduling decisions made are still valid by the time a job is to be executed, …

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Design And Analysis Of Application Architecture For Opportunistic Networks Using Ad Hoc Wi-Fi, Sankalp Vinod Shere Jan 2009

Design And Analysis Of Application Architecture For Opportunistic Networks Using Ad Hoc Wi-Fi, Sankalp Vinod Shere

Computer Science and Engineering Theses - Archive

In recent years, the number of smartphone users has increased by many folds. In fact, it is estimated to reach 100 million by 2013. Current generation of smartphones has better storage, battery, computing capabilities and they come equipped with short range communication technologies like Bluetooth and Wi-Fi. These improved capabilities coupled with staggering rise in number of users, has prompted growing interest in smartphone applications that help users to communicate with each other directly and over the internet. In particular as a result, when a large number of mobile users can communicate directly with each other during opportunistic contacts when …

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Reactive Control Composition For Mobile Manipulators, Binu George Mathew Jan 2009

Reactive Control Composition For Mobile Manipulators, Binu George Mathew

Computer Science and Engineering Theses - Archive

A mobile manipulator is a manipulator mounted on a mobile platform. Due to this combination it has increased mobility compared to a fixed manipulator and increased dexterity compared to a mobile platform. At the same time it has a significantly higher number of degrees of freedom than fixed manipulators or mobile platforms and an increased task and workspace. In particular, the size of the workspace of the manipulator is restricted only by the workspace limitations of the mobile platform and the obstacles around the goal location. In addition, the extra degrees of freedom increase the number of ways in which …

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Design And Analysis Of A Mobile File Sharing System For Opportunistic Networks, Gautam Ravendra Chavan Jan 2009

Design And Analysis Of A Mobile File Sharing System For Opportunistic Networks, Gautam Ravendra Chavan

Computer Science and Engineering Theses - Archive

In the past several years, wireless mobile devices with advanced computing, sensing, and storing capabilities have been increasingly developed by handset manufacturers, deployed by wireless carriers, and accepted by consumers. A prominent example is the vast success of Apple's iPhone, which witnessed a sale of 1 million units during the first 3 days of sales for its new version iPhone 3GS. As a result of the increasing popularity of these mobile devices, users can carry, utilize, and exchange information embedded therein, ideally wherever they go and whenever they want. A prominent scenario is where information is exchanged among users when …

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The Reputation System For Robust, Structured P2p Systems, Apurv Ashok Dhadphale Jan 2009

The Reputation System For Robust, Structured P2p Systems, Apurv Ashok Dhadphale

Computer Science and Engineering Theses - Archive

Structured peer-to-peer systems are distributed communication systems that typically use Distributed Hash Table (DHT) indexing to efficiently locate the resources. These networks are highly scalable and can route the messages correctly even for the extremely dynamic environment. But these networks are vulnerable; even a small fraction of malicious nodes can bias the lookup results when they are present on a lookup path. In our thesis, we address this problem of reliably searching the insecure p2p networks. We propose a reputation system to reduce the number of failed lookups and make the networks more robust. For our study, the concept is …

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Liquid: A Detection Resistant Covert Timing Channel Based On Ipd Shaping, Robert J. Walls Jan 2009

Liquid: A Detection Resistant Covert Timing Channel Based On Ipd Shaping, Robert J. Walls

Computer Science and Engineering Theses - Archive

Covert timing channels provide a way to surreptitiously leak information from an entity in a higher-security level to an entity in a lower level. The difficulty of detecting or eliminating such channels makes them a desirable choice for adversaries that value stealth over throughput. When one considers the possibility of such channels transmitting information across network boundaries, the threat becomes even more acute. A promising technique for detecting covert timing channels focuses on using entropy-based tests. This method is able to reliably detect known covert timing channels by using a combination of entropy and conditional entropy to detect anomalies in …

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Ionization Competitors Extend The Linear Range Of Electrospray Ionization Mass Spectrometry, Bilal H. Bazzi Jan 2009

Ionization Competitors Extend The Linear Range Of Electrospray Ionization Mass Spectrometry, Bilal H. Bazzi

Chemistry & Biochemistry Theses - Archive

ESI-MS has proven its applicability in quantitative analysis for a wide range of analytes. Its effectiveness relies on achieving sensitivity and linear range, although the latter is known to be limited. ESI-MS response varies among charged species due to differences in analyte structure. The working curve associated with quantitative analysis has a limit of linearity. At high analyte concentration, instrument response plateaus because the surface of the charged droplet reaches saturation. Several studies have proposed to enhance the linear range by enhancing gas-phase analyte charging, by facilitating droplet evaporation, or by improving ion transmission through the mass spectrometer. This thesis …

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A New Method For Non-Rigid Registration Of 3d Images, Mehmet Ali Akinlar Jan 2009

A New Method For Non-Rigid Registration Of 3d Images, Mehmet Ali Akinlar

Mathematics Dissertations - Archive

In this dissertation we present a novel method for the nonrigid registration of 3D images using a well-established mathematical framework mostly known as the deformation based grid generation method. The deformation based grid generation method is able to generate a grid with desired grid density distribution that is free from grid folding. This method gives direct control over the cell size of the adaptive grid and determines the node velocities directly. The adaptive grid system naturally distributes more grids to deprived areas. The positive monitor function disallows grid folding and provides a mean to control the ratio of the areas …

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Non-Traditional Socio-Mathematical Norms In Undergraduate Real Analysis, Paul Christian Dawkins Jan 2009

Non-Traditional Socio-Mathematical Norms In Undergraduate Real Analysis, Paul Christian Dawkins

Mathematics Dissertations - Archive

This study builds upon the framework of classroom norms (Cobb, Wood, & Yackel, 1993) and socio-mathematical norms (Cobb & Yackel, 1996) to understand how non-traditional socio-mathematical norms influence student reasoning and transitions to advanced mathematical thinking in undergraduate real analysis. The research involves a qualitative investigation of classroom instruction and interactions, student and instructor interviews, and class exams. The study explores the roles of each norm as the students constructed understanding of advanced mathematics and transitioned to advanced mathematical thinking. I define "non-traditional" according to research accounts of traditional instruction in proof-based mathematics courses and considerations on the culture of …

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Enantiomeric Separation, Microorganism Studies And Determination Of Binding Constants Using Capillary Electrophoresis, Chunxia Jiang Jan 2009

Enantiomeric Separation, Microorganism Studies And Determination Of Binding Constants Using Capillary Electrophoresis, Chunxia Jiang

Chemistry & Biochemistry Dissertations - Archive

Enantiomeric separation of three series of compounds, including β-lactams, synthetic amino acids and ruthenium(II) polypyridyl complexes using different modes of capillary electrophoresis are discussed in this dissertation. Enantiomeric recognition mechanisms are explored by studying the effect of the structures of chiral selectors and analytes. Results indicated that the size correlation between the analyte and the cyclodextrin cavity size play an important role in enantioseparation. Effects of experimental parameters including chiral selector concentration, buffer additive type and concentration, run buffer pH and applied voltage are studied for optimization of the enantioseparations. A new class of chiral selectors, cyclofructans were developed and …

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Large Deviation Principle For Functional Limit Theorems, Adina Oprisan Jan 2009

Large Deviation Principle For Functional Limit Theorems, Adina Oprisan

Mathematics Dissertations - Archive

We study a family of stochastic additive functionals of Markov processes with locally independent increments switched by jump Markov processes in an asymptotic split phase space. Based on an averaging limit theorem, we obtain a large deviation result for this stochastic evolutionary system using a weak convergence approach. Examples, including compound Poisson processes, illustrate cases in which the rate function is calculated in an explicit form.We prove also a large deviation principle for a class of empirical processes associated with additive functionals of Markov processes that were shown to have a martingale decomposition. Functional almost everywhere central limit theorems are …

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