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Articles 3121 - 3150 of 3529
Full-Text Articles in Physical Sciences and Mathematics
Building A Model Of Campus Diversity: An Organization-As-The-Individual Based Approach, Ian Spencer Ray
Building A Model Of Campus Diversity: An Organization-As-The-Individual Based Approach, Ian Spencer Ray
Electronic Theses and Dissertations
Diversity is a vital concept when engaging with modern social science research and among higher education practitioners. Despite the pervasive discourse surrounding diversity, equity, and inclusion (DEI) initiatives, quantification of diversity remains a challenge across the social sciences. This study proposes a new conceptual framework, applies the framework to the quantification of diversity and measurement of its impacts. Further, this study demonstrates the robustness of the new conceptual framework alongside the positive impacts of diversity on institutional outcomes.
The Organization-As-The-Individual (OATI) framework arises from an integration of the social and biological sciences. The framework argues that humans, as biological organisms, …
Using The Em Algorithm To Estimate The Difference In Dependent Proportions In A 2 X 2 Table With Missing Data., Alain Duclaux Talla Souop
Using The Em Algorithm To Estimate The Difference In Dependent Proportions In A 2 X 2 Table With Missing Data., Alain Duclaux Talla Souop
Electronic Theses and Dissertations
In this thesis, I am interested in estimating the difference between dependent proportions from a 2 × 2 contingency table when there are missing data. The Expectation-Maximization (EM) algorithm is used to obtain an estimate for the difference between correlated proportions. To obtain the standard error of this difference I employ a resampling technique known as bootstrapping. The performance of the bootstrap standard error is evaluated for different sample sizes and different fractions of missing information. Finally, a 100(1-α)% bootstrap confidence interval is proposed and its coverage is evaluated through simulation.
A Vulnerability Assessment Of The East Tennessee State University Administrative Computer Network., James Patrick Ashe
A Vulnerability Assessment Of The East Tennessee State University Administrative Computer Network., James Patrick Ashe
Electronic Theses and Dissertations
A three phase audit of East Tennessee State University's administrative computer network was conducted during Fall 2001, Spring 2002, and January 2004. Nmap and Nessus were used to collect the vulnerability data. Analysis discovered an average of 3.065 critical vulnerabilities per host with a low of 2.377 in Spring 2001 to a high of 3.694 in Fall 2001. The number of unpatched Windows operating system vulnerabilities, which accounted for over 75% of these critical vulnerabilities, strongly argues for the need of an automated patch deployment system for the approximately 3,000 Windows-based systems at ETSU.
Locating And Total Dominating Sets In Trees., Jamie Marie Howard
Locating And Total Dominating Sets In Trees., Jamie Marie Howard
Electronic Theses and Dissertations
A set S of vertices in a graph G=(V,E) is a total dominating set of G if every vertex of V is adjacent to some vertex in S. In this thesis, we consider total dominating sets of minimum cardinality which have the additional property that distinct vertices of V are totally dominated by distinct subsets of the total dominating set.
Differentials Of Graphs., Jason Robert Lewis
Differentials Of Graphs., Jason Robert Lewis
Electronic Theses and Dissertations
Let G=(V,E) be an arbitrary graph, and consider the following game. You are allowed to buy as many tokens from a bank as you like, at a cost of $1 each. For example, suppose you buy k tokens. You then place the tokens on some subset of k vertices of V. For each vertex of G which has no token on it, but is adjacent to a vertex with a token on it, you receive $1 from the bank. Your objective is to maximize your profit, that is, the total value received from the …
Determination Of Lactose By Reversed-Phase High Performance Liquid Chromatography., Danessa Leann Sexton
Determination Of Lactose By Reversed-Phase High Performance Liquid Chromatography., Danessa Leann Sexton
Electronic Theses and Dissertations
Lactose is the common disaccharide found in dairy products. It can, however, be a source of discomfort for those whom are lactose intolerant. Therefore, it is necessary to accurately, reliably, and efficiently determine the lactose content of foods. The goal of this research was to develop a reversed-phase HPLC method with UV detection for the determination of lactose. Aminobenzoic acid was used to prepare a derivative, making detection possible in the 300-360 nm region. The stationary phase is a C8 column, with 85% methanol 15% water mixture at pH 5 as the mobile phase. A linear response of peak area …
Study Of The Excited-State Absorption Properties Of Polymethine Molecules, Richard Stanley Lepkowicz
Study Of The Excited-State Absorption Properties Of Polymethine Molecules, Richard Stanley Lepkowicz
Electronic Theses and Dissertations
This dissertation investigates excited-state nonlinearities in a series of polymethine dyes for the application of nanosecond optical limiting. Optical limiters are devices that for low intensity light exhibit a high linear transmittance, but for high intensity light strongly attenuate the incident radiation. These devices would serve to protect optical sensors from intense laser radiation by clamping the maximum energy allowed through an optical system below the damage threshold of the sensor. The search is ongoing for optical materials that are both broadband and have high damage thresholds to be effective materials for limiting applications. Polymethine dyes are promising compounds due …
The Use Of Filters In Topology, Abdellatif Dasser
The Use Of Filters In Topology, Abdellatif Dasser
Electronic Theses and Dissertations
Sequences are sufficient to describe topological properties in metric spaces or, more generally, topological spaces having a countable base for the topology. However, filters or nets are needed in more abstract spaces. Nets are more natural extension of sequences but are generally less friendly to work with since quite often two nets have distinct directed sets for domains. Operations involving filters are set theoretic and generally certain to filters on the same set. The concept of a filter was introduced by H. Cartan in 1937 and an excellent treatment of the subject can be found in N. Bourbaki (1940).
Macmahon's Master Theorem And Infinite Dimensional Matrix Inversion, Vivian Lola Wong
Macmahon's Master Theorem And Infinite Dimensional Matrix Inversion, Vivian Lola Wong
Electronic Theses and Dissertations
MacMahon's Master Theorem is an important result in the theory of algebraic combinatorics. It gives a precise connection between coefficients of certain power series defined by linear relations. We give a complete proof of MacMahon's Master Theorem based on MacMahon's original 1960 proof. We also study a specific infinite dimensional matrix inverse due to C. Krattenthaler.
Neural Networks Satisfying Stone-Weiestrass Theorem And Approximating, Pinal Thakkar
Neural Networks Satisfying Stone-Weiestrass Theorem And Approximating, Pinal Thakkar
Electronic Theses and Dissertations
Neural networks are an attempt to build computer networks called artificial neurons, which imitate the activities of the human brain. Its origin dates back to 1943 when neurophysiologist Warren Me Cello and logician Walter Pits produced the first artificial neuron. Since then there has been tremendous development of neural networks and their applications to pattern and optical character recognition, speech processing, time series prediction, image processing and scattered data approximation. Since it has been shown that neural nets can approximate all but pathological functions, Neil Cotter considered neural network architecture based on Stone-Weierstrass Theorem. Using exponential functions, polynomials, rational functions …
New Organic/Inorganic Hybrid Sol-Gel Nanocomposite Materials For Raman Gain In Fiber Optics, Stephen James Andrasik
New Organic/Inorganic Hybrid Sol-Gel Nanocomposite Materials For Raman Gain In Fiber Optics, Stephen James Andrasik
Electronic Theses and Dissertations
The recent increased availability of additional wavelengths in the telecommunications window of about 1300-1600 nm has generated an interest in new optical materials and devices that can operate outside the normally used regions of 840 nm, 1310 nm, and 1550 nm. Specifically, methods to amplify fiber optical data transmission in the regions where there is limited or no existing methods to achieve amplification is of interest in the chemistry and photonic communities. Raman gain is one method that has been proposed to passively amplify optical data transmission through a distributed process. Amplification is obtained through a nonlinear light scattering process …
Adaptive Intelligent User Interfaces With Emotion Recognition, Fatma Nasoz
Adaptive Intelligent User Interfaces With Emotion Recognition, Fatma Nasoz
Electronic Theses and Dissertations
The focus of this dissertation is on creating Adaptive Intelligent User Interfaces to facilitate enhanced natural communication during the Human-Computer Interaction by recognizing users' affective states (i.e., emotions experienced by the users) and responding to those emotions by adapting to the current situation via an affective user model created for each user. Controlled experiments were designed and conducted in a laboratory environment and in a Virtual Reality environment to collect physiological data signals from participants experiencing specific emotions. Algorithms (k-Nearest Neighbor [KNN], Discriminant Function Analysis [DFA], Marquardt-Backpropagation [MBP], and Resilient Backpropagation [RBP]) were implemented to analyze the collected data signals …
Thermal Management, Beam Control,And Packaging Designs For High Power, Te-Yuan Chung
Thermal Management, Beam Control,And Packaging Designs For High Power, Te-Yuan Chung
Electronic Theses and Dissertations
Several novel techniques for controlling, managing and utilizing high power diode lasers are described. Low pressure water spray cooling for a high heat flux system is developed and proven to be an ideal cooling method for high power diode laser arrays. In order to enable better thermal and optical performance of diode laser arrays, a new and simple optical element, the beam control prism, is invented. It provides the ability to accomplish beam shaping and beam tilting at the same time. Several low thermal resistance diode packaging designs using beam control prisms are proposed, studied and produced. Two pump cavity …
Part I: Evaluation Of Russian Synthetic Compounds As A Potential Source Of New Drug Leads Agains Breast And Colon Cancer Part Ii: Isolation Of Beta-Amyrin Formate From Eucalyptus Viminalis Labill And Investigation Of Its Colon Cancer Activity, Mihaela Cohanoschi
Electronic Theses and Dissertations
Although modern medicine made great steps toward curing most diseases considered deadliest, yet cancer remains one of the major public health problems. The first part of this thesis investigates a new source of selective compounds that are potential candidates against cancer. Fifteen Russian compounds were tested in order to establish their efficiency against two types of cancer: human breast SK-Br-3 and colorectal carcinoma HT-29. The bioassay results show that seven of the new synthetic Russian compounds can be considered new drug leads, based upon their low toxicity and efficacy in slowing the growth of human breast cancer and colon cancer …
Demographics Of Western South Dakota Wetlands And Basins, Bryan A. Rieger
Demographics Of Western South Dakota Wetlands And Basins, Bryan A. Rieger
Electronic Theses and Dissertations
Wetlands, whether natural or man-made in origin, are an important feature of the semiarid landscape of western South Dakota. These wetlands have numerous social and economic values and functions for both landowners and non-owners, as well as for fish and wildlife species. For this reason, accurate information about wetland abundance, characteristics and distribution is important. These demographic summaries of wetland resources of western South Dakota were based on digital wetland data, as delineated by the U.S. Fish and Wildlife Service’s National Wetlands Inventory (NWI) office. Surface water covers approximately 257,006 ha or about 2.4% of the 10,810,700 ha of western …
Factors Influencing A Declining Pronghorn Population In Wind Cave National Park, South Dakota, Jaret D. Sievers
Factors Influencing A Declining Pronghorn Population In Wind Cave National Park, South Dakota, Jaret D. Sievers
Electronic Theses and Dissertations
Pronghorn (Antilocapra americana) were reintroduced into Wind Cave National Park (WCNP) in 1914 and thus, have inhabited the park for almost a century. A decline in the population has raised concern for the continued existence of pronghorn inside the park. Historically, pronghorn numbers reached greater than 300 individuals but were estimated to be less than 50 individuals during this study. Knowledge of food habits, genetic structure, causes of mortality, survival rates, and information related to movements were important to developing an understanding of factors contributing to this decline. Past studies have described spatial relationships and breeding behavior of adults and …
Effects Of Fire On The Nutritional Ecology Of Selected Ungulates In The Southern Black Hills, South Dakota, Teresa J. Zimmerman
Effects Of Fire On The Nutritional Ecology Of Selected Ungulates In The Southern Black Hills, South Dakota, Teresa J. Zimmerman
Electronic Theses and Dissertations
Research in the 1990s indicated that populations of white-tailed deer (Odocoileus virginianus) in the northern and central Black Hills had declined since the late 1970s likely due to habitat deterioration. In August 2000, the Jasper fire consumed nearly 35,000 ha of ponderosa pine (Pinus ponderosa) forest in the southern Black Hills. To ascertain the nutritional condition of white-tailed deer and mule deer (O. hemionus) and their response to fire, 5 adult white-tailed deer and 5 adult mule deer were collected in burned and unburned habitat, in February and August, 2002 and 2003. Collected deer were weighed and necropsied at a …
Evaluation Of The Photo-Induced Structural Mechanisms In Chalcogenide, Cedric Lopez
Evaluation Of The Photo-Induced Structural Mechanisms In Chalcogenide, Cedric Lopez
Electronic Theses and Dissertations
Chalcogenide glasses and their use in a wide range of optical, electronic and memory applications, has created a need for a more thorough understanding of material property variation as a function of composition and in geometries representative of actual devices. This study evaluates compositional dependencies and photo-induced structural mechanisms in As-S-Se chalcogenide glasses. An effective fabrication method for the reproducible processing of bulk chalcogenide materials has been demonstrated and an array of tools developed, for the systematic characterization of the resulting material's physical and optical properties. The influence of compositional variation on the physical properties of 13 glasses within the …
Camera System Support For Highway Transportation Using Mobile Devices, Le Minh
Camera System Support For Highway Transportation Using Mobile Devices, Le Minh
Electronic Theses and Dissertations
With the very fast growing technology in wireless, advancement in hardware and the dramatically falling cost of mobile computing devices such as PDA, handheld device, People nowadays can have a personal device that fits in their hand but has computing power as a desktop did few years ago. The same device now is able to communicate over a wireless network and view office document at the same time. The combination of size, power and flexibility makes the personal devices increasingly appear in many aspects of life. In this proposal, we focus on a simple yet useful application of mobile devices …
The Use Of Pyrosequencing For The Analysis Of Y Chromosome Single Nucleotide Polymorphisms, Jeremy Charles Fletcher
The Use Of Pyrosequencing For The Analysis Of Y Chromosome Single Nucleotide Polymorphisms, Jeremy Charles Fletcher
Electronic Theses and Dissertations
The potential value of the Y chromosome for forensic applications has been recognized for some time with the current work dedicated to Short Tandem Repeat analysis and Single Nucleotide Polymorphism (SNP) discovery. This study examined the ability of two different SNP analysis methods to determine if they could be utilized in forensic applications and ultimately be developed into an established system for Y chromosome SNP analysis. This study examined two principle SNP analysis systems: single base extension and Pyrosequencing. Pyrosequencing was determined to be superior to single base extension, due to the wealth of information provided with sequencing and the …
The Wave Structure Function And Temporal Frequency Spread In Weak To Strong Optical Turbulence, Aaron J. Masino
The Wave Structure Function And Temporal Frequency Spread In Weak To Strong Optical Turbulence, Aaron J. Masino
Electronic Theses and Dissertations
This paper presents analytic expressions for the wave structure function, frequency spread of the temporal frequency spectrum, and the temporal frequency spectrum of optical signals propagating through a random medium, specifically the Earth’s atmosphere. The results are believed to be valid for all optical turbulence conditions. These expressions are developed using the Rytov approximation method. Generally, the validity of statistical quantities obtained via this method is restricted to conditions of weak optical turbulence. However, in this work, by using a modification of the effective atmospheric spectral model presented by Andrews et al. for scintillation index, wave structure function expressions have …
Method For Determination Of Singlet Oxygen Quantum Yields For New Fluorene-Based Photosensitizers In Aqueous Media For The Advancement Of Photodynamic Therapy, Wade William Grabow
Method For Determination Of Singlet Oxygen Quantum Yields For New Fluorene-Based Photosensitizers In Aqueous Media For The Advancement Of Photodynamic Therapy, Wade William Grabow
Electronic Theses and Dissertations
Photodynamic therapy (PDT) has been investigated over the past three decades and is currently an approved therapeutic modality for skin cancer, the treatment of superficial bladder, early lung and advanced esophageal cancers, and age-related macular degeneration in a number of countries. In PDT, the absorption of light by a chromophore generates cytotoxic species such as reactive singlet oxygen, leading to irreversible destruction of the treated tissue. The measurement of the singlet oxygen quantum yield is an important determinant used to evaluate the efficiency of new photodynamic therapy agents developed in the laboratory, to screen potential photosensitizers in aqueous media.The singlet …
Chemical Structure - Nonlinear Optical Property Relationships For A Series Of Two-Photon Absorbing Fluorene Molecules, Joel Mccajah Hales
Chemical Structure - Nonlinear Optical Property Relationships For A Series Of Two-Photon Absorbing Fluorene Molecules, Joel Mccajah Hales
Electronic Theses and Dissertations
This dissertation reports on the investigation of two-photon absorption (2PA) in a series of fluorenyl molecules. Several current and emerging technologies exploit this optical nonlinearity including two-photon fluorescence imaging, three-dimensional microfabrication, site-specific photodynamic cancer therapy and biological caging studies. The two key features of this nonlinearity which make it an ideal candidate for the above applications are its quadratic dependence on the incident irradiance and the improved penetration into absorbing media that it affords. As a consequence of the burgeoning field which exploits 2PA, it is a goal to find materials that exhibit strong two-photon absorbing capabilities. Organic materials are …
Partitioning A Graph In Alliances And Its Application To Data Clustering, Khurram Hassan-Shafique
Partitioning A Graph In Alliances And Its Application To Data Clustering, Khurram Hassan-Shafique
Electronic Theses and Dissertations
Any reasonably large group of individuals, families, states, and parties exhibits the phenomenon of subgroup formations within the group such that the members of each group have a strong connection or bonding between each other. The reasons of the formation of these subgroups that we call alliances differ in different situations, such as, kinship and friendship (in the case of individuals), common economic interests (for both individuals and states), common political interests, and geographical proximity. This structure of alliances is not only prevalent in social networks, but it is also an important characteristic of similarity networks of natural and unnatural …
Selective Mode Excitation In Specialty Waveguides Using Micro Optical, Waleed Mohammed
Selective Mode Excitation In Specialty Waveguides Using Micro Optical, Waleed Mohammed
Electronic Theses and Dissertations
Although optical fibers and specialty waveguides are the base of majority of today's telecom and light delivery applications, fabrication deformation, nonlinearity and attenuation limit the bandwidth of the data being transmitted or the amount of power carried by these systems. One-way to overcome these limitations without changing the fibers design or fabrication is to engineer the input light in order to excite a certain mode or a group of modes with unique optical properties. Diffractive and micro optics are highly effective for selectively coupling light to specific modes. Using micro optics, mode selective coupling can be achieved through several matching …
Discrete Nonlinear Wave Propagation In Kerr Nonlinear Media, Joachim Meier
Discrete Nonlinear Wave Propagation In Kerr Nonlinear Media, Joachim Meier
Electronic Theses and Dissertations
Discrete optical systems are a subgroup of periodic structures in which the evolution of a continuous electromagnetic field can be described by a discrete model. In this model, the total field is the sum of localized, discrete modes. Weakly coupled arrays of single mode channel waveguides have been known to fall into this class of systems since the late 1960's. Nonlinear discrete optics has received a considerable amount of interest in the last few years, triggered by the experimental realization of discrete solitons in a Kerr nonlinear AlGaAs waveguide array by H. Eisenberg and coworkers in 1998. In this work …
Sinbad Automation Of Scientific Process: From Hidden Factor Analysis To Theory Synthesis, Olcay Kursun
Sinbad Automation Of Scientific Process: From Hidden Factor Analysis To Theory Synthesis, Olcay Kursun
Electronic Theses and Dissertations
Modern science is turning to progressively more complex and data-rich subjects, which challenges the existing methods of data analysis and interpretation. Consequently, there is a pressing need for development of ever more powerful methods of extracting order from complex data and for automation of all steps of the scientific process. Virtual Scientist is a set of computational procedures that automate the method of inductive inference to derive a theory from observational data dominated by nonlinear regularities. The procedures utilize SINBAD – a novel computational method of nonlinear factor analysis that is based on the principle of maximization of mutual information …
The Proteomics Approach To Evolutionary Computation: An Analysis Of Pr, Ivan Garibay
The Proteomics Approach To Evolutionary Computation: An Analysis Of Pr, Ivan Garibay
Electronic Theses and Dissertations
As the complexity of our society and computational resources increases, so does the complexity of the problems that we approach using evolutionary search techniques. There are recent approaches to deal with the problem of scaling evolutionary methods to cope with highly complex difficult problems. Many of these approaches are biologically inspired and share an underlying principle: a problem representation based on basic representational building blocks that interact and self-organize into complex functions or designs. The observation from the central dogma of molecular biology that proteins are the basic building blocks of life and the recent advances in proteomics on analysis …
High Performance Data Mining Techniques For Intrusion Detection, Muazzam Ahmed Siddiqui
High Performance Data Mining Techniques For Intrusion Detection, Muazzam Ahmed Siddiqui
Electronic Theses and Dissertations
The rapid growth of computers transformed the way in which information and data was stored. With this new paradigm of data access, comes the threat of this information being exposed to unauthorized and unintended users. Many systems have been developed which scrutinize the data for a deviation from the normal behavior of a user or system, or search for a known signature within the data. These systems are termed as Intrusion Detection Systems (IDS). These systems employ different techniques varying from statistical methods to machine learning algorithms. Intrusion detection systems use audit data generated by operating systems, application softwares or …
Dynamic Shared State Maintenance In Distributed Virtual Environments, Felix George Hamza-Lup
Dynamic Shared State Maintenance In Distributed Virtual Environments, Felix George Hamza-Lup
Electronic Theses and Dissertations
Advances in computer networks and rendering systems facilitate the creation of distributed collaborative environments in which the distribution of information at remote locations allows efficient communication. Particularly challenging are distributed interactive Virtual Environments (VE) that allow knowledge sharing through 3D information. In a distributed interactive VE the dynamic shared state represents the changing information that multiple machines must maintain about the shared virtual components. One of the challenges in such environments is maintaining a consistent view of the dynamic shared state in the presence of inevitable network latency and jitter. A consistent view of the shared scene will significantly increase …