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Electronic Theses and Dissertations

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Articles 3541 - 3570 of 4194

Full-Text Articles in Physical Sciences and Mathematics

A Sparse Program Dependence Graph For Object Oriented Programming Languages, Keith Garfield Jan 2006

A Sparse Program Dependence Graph For Object Oriented Programming Languages, Keith Garfield

Electronic Theses and Dissertations

The Program Dependence Graph (PDG) has achieved widespread acceptance as a useful tool for software engineering, program analysis, and automated compiler optimizations. This thesis presents the Sparse Object Oriented Program Dependence Graph (SOOPDG), a formalism that contains elements of traditional PDG's adapted to compactly represent programs written in object-oriented languages such as Java. This formalism is called sparse because, in contrast to other OO and Java-specific adaptations of PDG's, it introduces few node types and no new edge types beyond those used in traditional dependence-based representations. This results in correct program representations using smaller graph structures and simpler semantics when …


Polarimetry Of Random Fields, Jeremy Ellis Jan 2006

Polarimetry Of Random Fields, Jeremy Ellis

Electronic Theses and Dissertations

On temporal, spatial and spectral scales which are small enough, all fields are fully polarized. In the optical regime, however, instantaneous fields can rarely be examined, and, instead, only average quantities are accessible. The study of polarimetry is concerned with both the description of electromagnetic fields and the characterization of media a field has interacted with. The polarimetric information is conventionally presented in terms of second order field correlations which are averaged over the ensemble of field realizations. Motivated by the deficiencies of classical polarimetry in dealing with specific practical situations, this dissertation expands the traditional polarimetric approaches to include …


Fast Response Liquid Crystal Devices, Yung-Hsun Wu Jan 2006

Fast Response Liquid Crystal Devices, Yung-Hsun Wu

Electronic Theses and Dissertations

Liquid crystal (LC) has been widely used for displays, spatial light modulators, variable optical attenuators (VOAs) and other tunable photonic devices. The response time of these devices is mainly determined by the employed liquid crystal material. How to obtain fast response for the LC devices is a fundamentally important and technically challenging task. In this dissertation, we investigate several methods to improve liquid crystal response time, for examples, using dual-frequency liquid crystals, polymer stabilized liquid crystals, and sheared polymer network liquid crystals. We discover a new class of material, denoted as sheared polymer network liquid crystal (SPNLC) which exhibits a …


Modeling And Characterizations Of New Notions In Life Testing With Statistical Applications, Mohammad Sepehrifar Jan 2006

Modeling And Characterizations Of New Notions In Life Testing With Statistical Applications, Mohammad Sepehrifar

Electronic Theses and Dissertations

Knowing the class to which a life distribution belongs gives us an idea about the aging of the device or system the life distribution represents, and enables us to compare the aging properties of different systems. This research intends to establish several new nonparametric classes of life distributions defined by the concept of inactivity time of a unit with a guaranteed minimum life length. These classes play an important role in the study of reliability theory, survival analysis, maintenance policies, economics, actuarial sciences and many other applied areas.


Modeling, Simulation, And Visualization Of 3d Lung Dynamics, Anand Santhanam Jan 2006

Modeling, Simulation, And Visualization Of 3d Lung Dynamics, Anand Santhanam

Electronic Theses and Dissertations

Medical simulation has facilitated the understanding of complex biological phenomenon through its inherent explanatory power. It is a critical component for planning clinical interventions and analyzing its effect on a human subject. The success of medical simulation is evidenced by the fact that over one third of all medical schools in the United States augment their teaching curricula using patient simulators. Medical simulators present combat medics and emergency providers with video-based descriptions of patient symptoms along with step-by-step instructions on clinical procedures that alleviate the patient's condition. Recent advances in clinical imaging technology have led to an effective medical visualization …


Polarization-Independent Liquid Crystal Devices, Yi-Hsin Lin Jan 2006

Polarization-Independent Liquid Crystal Devices, Yi-Hsin Lin

Electronic Theses and Dissertations

Liquid crystal (LC) devices can be operated as amplitude modulators and phase modulators. LC amplitude modulation is commonly used in liquid crystal display (LCD) while phase-only modulation is useful for laser beam steering, tunable grating, prism, lens, and other photonic devices. Most LC devices are polarization dependent and require at least one polarizer. As a result, the optical efficiency is low. To enhance display brightness, a power hungry backlight has to be used leading to a high power consumption and short battery life. In a LC phase modulator, the polarization dependent property complicates the laser beam steering system. It is …


Experimental Techniques For Nonlinear Material Characterization: A Nonlinear Spectrometer Using A White-Light Continuum Z-Scan, Mihaela Balu Jan 2006

Experimental Techniques For Nonlinear Material Characterization: A Nonlinear Spectrometer Using A White-Light Continuum Z-Scan, Mihaela Balu

Electronic Theses and Dissertations

The main goal of this dissertation is to introduce and demonstrate a new method for the rapid determination of the nonlinear absorption spectra and the dispersion of the nonlinear refraction of optical materials in the visible and near IR spectral regions. However, conventional methods like, white-light continuum pump-probe and Z-scan techniques were used to measure the peak 2PA cross-sections for a number of commercially available photoinitiators. In the new method mentioned above, a high energy, broadband femtosecond white-light continuum is used to replace the single wavelength source conventionally used in a Z-scan experiment. In a Z-scan experiment, the transmittance of …


Video Content Extraction: Scene Segmentation, Linking And Attention Detection, Yun Zhai Jan 2006

Video Content Extraction: Scene Segmentation, Linking And Attention Detection, Yun Zhai

Electronic Theses and Dissertations

In this fast paced digital age, a vast amount of videos are produced every day, such as movies, TV programs, personal home videos, surveillance video, etc. This places a high demand for effective video data analysis and management techniques. In this dissertation, we have developed new techniques for segmentation, linking and understanding of video scenes. Firstly, we have developed a video scene segmentation framework that segments the video content into story units. Then, a linking method is designed to find the semantic correlation between video scenes/stories. Finally, to better understand the video content, we have developed a spatiotemporal attention detection …


Real-Time Monocular Vision-Based Tracking For Interactive Augmented Reality, Lisa Spencer Jan 2006

Real-Time Monocular Vision-Based Tracking For Interactive Augmented Reality, Lisa Spencer

Electronic Theses and Dissertations

The need for real-time video analysis is rapidly increasing in today's world. The decreasing cost of powerful processors and the proliferation of affordable cameras, combined with needs for security, methods for searching the growing collection of video data, and an appetite for high-tech entertainment, have produced an environment where video processing is utilized for a wide variety of applications. Tracking is an element in many of these applications, for purposes like detecting anomalous behavior, classifying video clips, and measuring athletic performance. In this dissertation we focus on augmented reality, but the methods and conclusions are applicable to a wide variety …


Sources And Deposition Processes Linking Atmospheric Chemistry And Firn Records From Four Glacier Accumulation Zones In The Mcmurdo Dry Valleys, Antarctica, Bruce R. Williamson Jan 2006

Sources And Deposition Processes Linking Atmospheric Chemistry And Firn Records From Four Glacier Accumulation Zones In The Mcmurdo Dry Valleys, Antarctica, Bruce R. Williamson

Electronic Theses and Dissertations

Samples of snow and firn from accumulation zones on the Victoria Upper Glacier, the Clark Glacier, the Commonwealth Glacier and the Blue Glacier in the McMurdo Dry Valleys (~77 to 78º S and 161 to 164º E), Antarctica, are evaluated chemically and isotopically to determine the relative importance of local (site-specific) factors versus regional-scale climatic influences in defining regional glaciochemistry. Two approaches for distinguishing these controls are examined: comparing chemical concentrations using multivariate statistical analysis, and examining the effect of physical filtration (capturing particulate material largely originating in close proximity to each site) on sample values. These techniques provide constraints …


The Geoarchaeological Setting Of The Sebasticook Lake Fish Weir Newport, Maine, Christopher Evan Miller Jan 2006

The Geoarchaeological Setting Of The Sebasticook Lake Fish Weir Newport, Maine, Christopher Evan Miller

Electronic Theses and Dissertations

A geophysical and coring survey of Sebasticook Lake, Newport, Maine, provides evidence of past human-landscape interactions associated with construction and use of a Middle Archaic to Middle Woodland period fish weir, located at the lake inlet. Geophysical methods employed included Seismic Reflection Profiling (SRP) and Sidescan Sonar (SSS) survey of the Sebasticook Lake basin, and Ground Penetrating Radar (GPR) survey of the fish weir site and lake inlet. Three cores were collected using a modified, square-rod Wright piston corer in the lake basin. The Sebasticook fish weir complex consists of >630 stone-tool-modified wooden stakes, driven into stiff underlying glacial mud …


Monitoring Pc Hardware Sounds In Linux Systems Using The Daubechies D4 Wavelet., Robert Karns Henry Dec 2005

Monitoring Pc Hardware Sounds In Linux Systems Using The Daubechies D4 Wavelet., Robert Karns Henry

Electronic Theses and Dissertations

Users of high availability (HA) computing require systems that run continuously, with little or no downtime. Modern PCs address HA needs by monitoring operating system parameters such as voltage, temperature, and hard drive status in order to anticipate possible system failure. However, one modality for PC monitoring that has been underutilized is sound. The application described here uses wavelet theory to analyze sounds produced by PC hard drives during standard operation. When twenty-nine hard drives were tested with the application and the results compared with the drives' Self-Monitoring, Analysis, and Reporting Technology (S.M.A.R.T.) data, the binomial distribution's low p-value of …


A Microreactor System For Measuring Size Selectivity In Porous Wo3 Sensor Materials, Meng Lu Dec 2005

A Microreactor System For Measuring Size Selectivity In Porous Wo3 Sensor Materials, Meng Lu

Electronic Theses and Dissertations

Our interest in studying reactions catalyzed by high surface area W03 powders is based on their potential application as the active material in sensors for low level (ppb) detection of flammable or toxic gases. A series of porous W03 powders with both meso- and micro-porosity have been synthesized by Waghe and Tripp. Preliminary results of the response of sensors fabricated from these materials indicated the possibility of size selectivity on the molecular scale. To provide support for the hypothesis of size selectivity and understand the reaction kinetics of alcohols over the new porous W03 powders for sensor …


Extensions Of The Cayley-Hamilton Theorem With Applications To Elliptic Operators And Frames., Alberto Mokak Teguia Aug 2005

Extensions Of The Cayley-Hamilton Theorem With Applications To Elliptic Operators And Frames., Alberto Mokak Teguia

Electronic Theses and Dissertations

The Cayley-Hamilton Theorem is an important result in the study of linear transformations over finite dimensional vector spaces. In this thesis, we show that the Cayley-Hamilton Theorem can be extended to self-adjoint trace-class operators and to closed self-adjoint operators with trace-class resolvent over a separable Hilbert space. Applications of these results include calculating operators resolvents and finding the inverse of a frame operator.


Cell Toxicity And Uptake Of Rrr-Alpha-Tocopheryl Polyethylene Glycol 1000 Succinate (Tpgs) By Various Cell Ines In Vitro., Christelle Komguem Kamga Aug 2005

Cell Toxicity And Uptake Of Rrr-Alpha-Tocopheryl Polyethylene Glycol 1000 Succinate (Tpgs) By Various Cell Ines In Vitro., Christelle Komguem Kamga

Electronic Theses and Dissertations

This research focused on investigating and comparing the cytotoxicity and cellular uptake of RRR-alpha-tocopheryl polyethylene glycol succinate (TPGS, with that of alpha-tocopheryl succinate (α-TS). Both TPGS and α-TS are water-soluble forms of vitamin E with important clinical applications. Cytotoxicity assays with RAW 264.7 and LNCaP cells incubated overnight with TPGS or α-TS at concentrations ≥ 12.4 μM suggest that α-TS is more cytotoxic than TPGS. Macrophages were found to be more sensitive than LNCaP cells when treated with similar concentrations of α-TS. For both cell lines, most of the TPGS or α-TS taken up remained esterified after 24 hours. Our …


The Interquartile Range: Theory And Estimation., Dewey Lonzo Whaley Aug 2005

The Interquartile Range: Theory And Estimation., Dewey Lonzo Whaley

Electronic Theses and Dissertations

The interquartile range (IQR) is used to describe the spread of a distribution. In an introductory statistics course, the IQR might be introduced as simply the “range within which the middle half of the data points lie.” In other words, it is the distance between the two quartiles, IQR = Q3 - Q1. We will compute the population IQR, the expected value, and the variance of the sample IQR for various continuous distributions. In addition, a bootstrap confidence interval for the population IQR will be evaluated.


Evaluating The Effectiveness Of A Company's Online Health And Safety Training Program By Assessing Its Employees Perceptions And Knowledge., Jo Nell Maynard Mullins Aug 2005

Evaluating The Effectiveness Of A Company's Online Health And Safety Training Program By Assessing Its Employees Perceptions And Knowledge., Jo Nell Maynard Mullins

Electronic Theses and Dissertations

A cross-sectional study was conducted to evaluate a company’s online H & S training program. The ABC Company’s online 8-hr HAZWOPER refresher course is based on current OSHA standard topics required for certification and principles flexible to fit site- or task-specific situations and conditions.

An 18-question survey was used to evaluate employee perceptions of online training compared to traditional classroom training. Perceptions were compared by demographic variables (e.g. gender, position, race, age and longevity with the ABC Company), which suggested that only age had an influence on employee response. Fifty-five percent of the employees surveyed preferred online training as compared …


Potential Energy Surface Around The Tropylium Ion., Kenneth Wayne Bullins Aug 2005

Potential Energy Surface Around The Tropylium Ion., Kenneth Wayne Bullins

Electronic Theses and Dissertations

The formation of the tropylium ion, C7H7+, in the mass spectrum of toluene is a chemical process that has been studied extensively in the past. The advances in computational power of personal computers have made the investigation of the pathway to form this ion and its subsequent decomposition feasible at a fairly high level of theory. The calculations that we performed were at the HF/6-31G (d, p) and the B3LYP/6-311++G (2d) levels. This work will show areas of the potential energy surface around the highly symmetric tropylium ion to give a glance of possible mechanisms …


A Limit Theorem In Cryptography., Kevin Lynch Aug 2005

A Limit Theorem In Cryptography., Kevin Lynch

Electronic Theses and Dissertations

Cryptography is the study of encryptying and decrypting messages and deciphering encrypted messages when the code is unknown. We consider Λπx, Δy) which is a count of how many ways a permutation satisfies a certain property. According to Hawkes and O'Connor, the distribution of Λπx, Δy) tends to a Poisson distribution with parameter ½ as m → ∞ for all Δxy ∈ (Z/qZ)m - 0. We give a proof of this theorem using the Stein-Chen method: As qm …


Cell Toxicology Study Of Rrr-Alpha-Tocopheryl Polyethylene Glycol 1000 Succinate (Tpgs)., Clarisse Sornsay Muenyi Aug 2005

Cell Toxicology Study Of Rrr-Alpha-Tocopheryl Polyethylene Glycol 1000 Succinate (Tpgs)., Clarisse Sornsay Muenyi

Electronic Theses and Dissertations

This research focused on the cytotoxic properties of RRR-alpha-tocopheryl polyethylene glycol 1000 succinate (TPGS) in transformed and cancerous cell lines. We used RAW264.7 macrophage and prostate cancer (LNCaP) cell lines in this study. TPGS caused cell death and decreased cell viability in a dose and time dependent manner. Cell death was evaluated fluorimetrically by employing the nucleic acid-binding fluorophore; propidium iodide. A colorimetric 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay was used to evaluate cell viability. Cell death can occur through necrosis or apoptosis. Our results suggested that TPGS triggered apoptotic cell death. Induction of apoptosis, as measured by caspase …


Paired And Total Domination On The Queen's Graph., Paul Asa Burchett Aug 2005

Paired And Total Domination On The Queen's Graph., Paul Asa Burchett

Electronic Theses and Dissertations

The Queen’s domination problem has a long and rich history. The problem can be simply stated as: What is the minimum number of queens that can be placed on a chessboard so that all squares are attacked or occupied by a queen? The problem has been expanded to include not only the standard 8x8 board, but any rectangular m×n sized board. In this thesis, we consider both paired and total domination versions of this renowned problem.


Electrochemical Remedy And Analysis For The Environment Based On The New Polymer-Dna Composite Material., Noor Feuza Hussain Aug 2005

Electrochemical Remedy And Analysis For The Environment Based On The New Polymer-Dna Composite Material., Noor Feuza Hussain

Electronic Theses and Dissertations

In this work a new material, the conducting polymer-DNA composite, has been reported for the first time due to its promise in micro extraction, transfer, and release of cations under controlled potential conditions by using electrochemically assisted solid phase micro extraction (SPME). The Polypyrrole/DNA composite can be formed easily by oxidation of pyrrole monomers in the presence of chromosomal DNA by electropolymerization. Environmental significant pollutants such as Cd, Pb, Hg, Co, Zn, Cu, and Bi metal ions can be extracted from the aqueous solution and are able to be transferred to another medium defined as the release solution where the …


Bicyclic Mixed Triple Systems., Benkam Benedict Bobga Aug 2005

Bicyclic Mixed Triple Systems., Benkam Benedict Bobga

Electronic Theses and Dissertations

In the study of triple systems, one question faced is that of finding for what order a decomposition exists. We state and prove a necessary and sufficient condition for the existence of a bicyclic mixed triple system based on the three possible partial orientations of the 3-cycle with twice as many arcs as edges. We also explore the existence of rotational and reverse mixed triple systems. Our principal proof technique applied is the difference method. Finally, this work contains a result on packing of complete mixed graphs on v vertices, Mv, with isomorphic copies of two …


Rocket Powered Flight As A Perturbation To The Two-Body Problem., Clayton Jeremiah Clark Aug 2005

Rocket Powered Flight As A Perturbation To The Two-Body Problem., Clayton Jeremiah Clark

Electronic Theses and Dissertations

The two body problem and the rocket equation + ∊ α + k/r3r = 0 have been expressed in numerous ways. However, the combination of the rocket equation with the two-body problem has not been studied to any degree of depth due to the intractability of the resulting non-linear, non-homogeneous equations. The goal is to use perturbation techniques to approximate solutions to the combined two-body and rocket equations.


Implications Of Spatial Autocorrelation And Dispersal For The Modeling Of Species Distributions, Volker Bahn Aug 2005

Implications Of Spatial Autocorrelation And Dispersal For The Modeling Of Species Distributions, Volker Bahn

Electronic Theses and Dissertations

Modeling the geographical distributions of wildlife species is important for ecology and conservation biology. Spatial autocorrelation in species distributions poses a problem for distribution modeling because it invalidates the assumption of independence among sample locations. I explored the prevalence and causes of spatial autocorrelation in data from the Breeding Bird Survey, covering the conterminous United States, using Regression Trees, Conditional Autoregressive Regressions (CAR), and the partitioning of variance. I also constructed a simulation model to investigate dispersal as a process contributing to spatial autocorrelation, and attempted to verify the connection between dispersal and spatial autocorrelation in species' distributions in empirical …


Survival Model And Estimation For Lung Cancer Patients., Xingchen Yuan May 2005

Survival Model And Estimation For Lung Cancer Patients., Xingchen Yuan

Electronic Theses and Dissertations

Lung cancer is the most frequent fatal cancer in the United States. Following the notion in actuarial math analysis, we assume an exponential form for the baseline hazard function and combine Cox proportional hazard regression for the survival study of a group of lung cancer patients. The covariates in the hazard function are estimated by maximum likelihood estimation following the proportional hazards regression analysis. Although the proportional hazards model does not give an explicit baseline hazard function, the baseline hazard function can be estimated by fitting the data with a non-linear least square technique. The survival model is then examined …


Graph Theory For The Secondary School Classroom., Dayna Brown Smithers May 2005

Graph Theory For The Secondary School Classroom., Dayna Brown Smithers

Electronic Theses and Dissertations

After recognizing the beauty and the utility of Graph Theory in solving a variety of problems, the author decided that it would be a good idea to make the subject available for students earlier in their educational experience. In this thesis, the author developed four units in Graph Theory, namely Vertex Coloring, Minimum Spanning Tree, Domination, and Hamiltonian Paths and Cycles, which are appropriate for high school level.


Extending The Abstract Data Model., Matthew Bryston Winegar May 2005

Extending The Abstract Data Model., Matthew Bryston Winegar

Electronic Theses and Dissertations

The Abstract Data Model (ADM) was developed by Sanderson [19] to model and predict semantic loss in data translation between computer languages. In this work, the ADM was applied to eight languages that were not considered as part of the original work. Some of the languages were found to support semantic features, such as the restriction semantics for inheritance found in languages like XML Schemas and Java, which could not be represented in the ADM. A proposal was made to extend the ADM to support these semantic features, and the requirements and implications of implementing that proposal were considered.


Using Domination To Analyze Rna Structures., Travis Reves Coake May 2005

Using Domination To Analyze Rna Structures., Travis Reves Coake

Electronic Theses and Dissertations

Understanding RNA molecules is important to genomics research. Recently researchers at the Courant Institute of Mathematical Sciences used graph theory to model RNA molecules and provided a database of trees representing possible secondary RNA structures. In this thesis we use domination parameters to predict which trees are more likely to exist in nature as RNA structures. This approach appears to have promise in graph theory applications in genomics research.


The Challenges Of Network Security Remediation At A Regional University., William R. Simons May 2005

The Challenges Of Network Security Remediation At A Regional University., William R. Simons

Electronic Theses and Dissertations

This thesis describes challenges encountered during a year-long effort to improve the security of the 3,300 node administrative computer network at East Tennessee State University. The key remediation strategies used included employing the vulnerability scanner Nessus to profile the network, analyzing the scan results, and attempting to remove the most critical vulnerabilities found. The project succeeded in decreasing known “high” criticality vulnerabilities on campus by 26.1%, and confirmed four standard observations about the challenges of network administration:

  • Vulnerability scanning is a lengthy task best performed in parallel and supported by automated data analysis.
  • Securing a network is like trying to …