Physical Sciences and Mathematics Commons^™

A Contrast Pattern Based Clustering Algorithm For Categorical Data, Neil Koberlein Fore

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The data clustering problem has received much attention in the data mining, machine learning, and pattern recognition communities over a long period of time. Many previous approaches to solving this problem require the use of a distance function. However, since clustering is highly explorative and is usually performed on data which are rather new, it is debatable whether users can provide good distance functions for the data. This thesis proposes a Contrast Pattern based Clustering (CPC) algorithm to construct clusters without a distance function, by focusing on the quality and diversity/richness of contrast patterns that contrast the clusters in a …

Biodegradation Of Groundwater Pollutants (Chlorinated Hydrocarbons) In Vegetated Wetlands: Role Of Aerobic Microbes Naturally Associated With Roots Of Common Plants, Christina Lynn Powell

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Chlorinated aliphatic hydrocarbons (CAHs) are often found as groundwater contaminants because of past industrial activities and disposal practices. CAHs pose a threat to human health and thus, create a need to find both natural and engineered processes that can remove these chlorinated compounds from the environment. Natural attenuation by oxidative biodegradation is especially important because it can allow for mineralization to carbon dioxide, a nontoxic end-product. The goal of this research was to evaluate the potential oxidative biodegradation of CAHs by microorganisms that are naturally associated with wetland plant roots. The research was divided into field work and laboratory batch …

Fabrication Of Zinc Oxide Thin Films For Renewable Energy And Sensor Applications, Theresa Y. Hill

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Progress in commercializing renewable energy technologies is being advanced by developments in Zinc Oxide material science. The photovoltaic cell, for example, generates electricity by receiving solar energy into the cell, generating electrons, and simultaneously transporting electrical charge out of the cell. Metals are capable of removing electrical charge but block transmission of sunshine. Glass and plastics are capable of transmitting sunshine but block the removal of electrical charge. Therefore an exterior layer that is both optically transparent and electrically conductive is desirable. Transparent conductive oxides (TCOs) are the ideal material for such applications since they are capable of both functions. …

Routes To Sydno[3,4-A]Quinoxalines, Erik Dihrkop

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In the present work, the reactivity of alkyl and aryl sydnoquinoxalines was studied. Using a previously developed method, triphenylphosphine-2-(3-sydnonyl)phenylimide was prepared in a two-step process via a diazotization / azidation process of 3-(2-aminophenyl)sydnone, followed by treatment with triphenylphosphine. Due to the inability to achieve previously reported yields, a new, one-step method using Mitsunobu conditions was employed to synthesize the iminophosphorane in a good yield. A similar, brominated iminophosphorane was synthesized using the same conditions in a good yield. Treatment of both the brominated and non-brominated iminophosphoranes with alkyl and aryl isocyanates or isothiocyanates in an aza-Wittig process, gave the corresponding …

Conversion Of Carbon Dioxide And Hydrogen Into Methane In Bench-Scale Microcosms And Packed Column Reactors, Brian Alexander Congiu

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Escalating energy demands, rising costs, and increasing awareness of the environmental impacts of current energy sources have created an immediate need for sustainable, alternative energy resources and innovative fuel technologies. It is believed that a potential carbon-neutral fuel source can be generated through the microbial production of methane gas by methanogenic archaea. Carbon dioxide captured from the atmosphere and renewable production of hydrogen can be used to support these microorganisms for the large-scale production of methane. Bench-scale investigations involving 160 mL serum bottle batch experiments and two 11L packed-column reactors were conducted to evaluate the feasibility and efficiency of microbial …

Evolution And Analysis Of Neuromorphic Flapping-Wing Flight Controllers, Sanjay Kumar Boddhu

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The control of insect-sized flapping-wing micro air vehicles is attracting increasing interest. Solution of the problem requires construction of a controller that is physically small, extremely power efficient, and capable. In addition, process variation in the creation of very small wings and armatures as well as the potential for accumulating damage and wear over the course of a vehicle's lifetime suggest that controllers be able to self-adapt to the specific and possibly changing nature of the vehicles in which they are embedded. Previous work with Evolvable Hardware Continuous Time Recurrent Neural Networks (CTRNNs) as applied to adaptive control of walking …

Electrochemical Oxidation Of Ethanol In Ionic Liquids And Its Possible Use In Fuel Cells, Ashley M. Mason

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Electrochemical properties of EtOH in EMImBF4 ionic liquid were investigated and compared to the electrochemical properties of EtOH in 0.1M HClO4/H2O. As was shown earlier, oxidation of EtOH in HClO4/H2O involves formation of PtO on the electrode surface, which makes the electrode poisoned. We have found that the best procedure for removal of PtO from the Pt electrode is heating the electrode in concentrated H2SO4. Cyclic voltammograms obtained after cleaning several Pt electrodes conforms that this treatment gives clean Pt electrodes without any PtO. Electrochemical oxidation of EtOH in EMImBF4 ionic liquid show that is poisoning of Pt electrode by …

Transport Through Georeservoirs: Spatial Entropy In Hydraulic Properties, And Temporal Entropy In Residence Time Distributions, Lumeng Huang

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The general principle of maximum entropy can be used to guide the construction of flow and transport models parameters when are uncertain. The principle states that the model which maximizes the entropy should be chosen so that the full multiplicity or uncertainty is represented in the model outcomes.

In models for flow and transport through georeservoirs, the principle would commonly be applicable to the uncertainty in the model outcome for the time of travel through the system, in order to represent the full range of multiplicity in the distribution of residence times. Importantly, the model which maximizes the entropy in …

A Novel Synergistic Diagnosis Methodology For Identifying Abnormalities In Wireless Capsule Endoscopy Videos, Alexandros Karargyris

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Wireless Capsule Endoscopy (WCE) is a new technology that allows medical personnel to view the gastrointestinal (GI) mucosa. It is a swallowable miniature capsule device the size of a pill that transmits thousands of screenshots of the digestive tract to a wearable receiver. When the procedure finishes the video is uploaded to a workstation for viewing. Capsule Endoscopy has been established as a tool to identify various gastrointestinal (GI) conditions, such as blood-based abnormalities, polyps, ulcers, Crohn's disease in the small intestine, where the classical endoscopy is not regularly used.

As of 2009 the market is dominated by Given Imaging …

Sulfur-Tolerant Catalyst For The Solid Oxide Fuel Cell, Bozeman Joe Frank Iii

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JP-8 fuel is easily accessible, transportable, and has hydrogen content essential to solid oxide fuel cell (SOFC) operation. However, this syngas has sulfur content which results in a poisonous hydrogen sulfide that degrades electrochemical activity and causes complete SOFC failure in some cases. The goal is to synthesize and verify a cost-effective, catalyst supported on cerium oxide that either stabilizes ionic conductivity in the presence of hydrogen sulfide and/or is highly sulfur-resistant. After thorough computational analysis, it was concluded that the platinum-copper skin catalyst was the most cost-effective, sulfur-resistant catalyst. Experimental synthesis of copper, platinum, and platinum-copper skin catalysts supported …

Skeletal Pathology Of Tibiotarsi In Chick Embryos Exposed To Platinum Group Metals By Micro-Raman Spectroscopy, Jennifer L. Monahan

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Platinum group metals (PGMs) have been shown to accumulate in various tissues of organisms but their toxicity is not well-known. Raman spectroscopy is a powerful analytical technique that enables direct and non-destructive chemical characterization of bone tissues. PGMs were injected into chick embryos in the following concentrations: 0.1, 1.0, 5.0, or 10.0 ppm solutions of Pt^(IV), Rh^(III), Pd^(II) or PGMs mixtures (0.1 ppm or 1.0 ppm of each metal). The micro-Raman maps recorded on the paraffin embedded tibiotarsus cross-sections showed significant changes in the chemical composition and structure of the bone tissue as a result …

Semantic Provenance: Modeling, Querying, And Application In Scientific Discovery, Satya Sanket Sahoo

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Provenance metadata, describing the history or lineage of an entity, is essential for ensuring data quality, correctness of process execution, and computing trust values. Traditionally, provenance management issues have been dealt with in the context of workflow or relational database systems. However, existing provenance systems are inadequate to address the requirements of an emerging set of applications in the new eScience or Cyberinfrastructure paradigm and the Semantic Web. Provenance in these applications incorporates complex domain semantics on a large scale with a variety of uses, including accurate interpretation by software agents, trustworthy data integration, reproducibility, attribution for commercial or legal …

Understanding User-Generated Content On Social Media, Bala Meenakshi Nagarajan

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Over the last few years, there has been a growing public and enterprise fascination with 'social media' and its role in modern society. At the heart of this fascination is the ability for users to participate, collaborate, consume, create and share content via a variety of platforms such as blogs, micro-blogs, email, instant messaging services, social network services, collaborative wikis, social bookmarking sites, and multimedia sharing sites.

This dissertation is devoted to understanding informal user-generated textual content on social media platforms and using the results of the analysis to build Social Intelligence Applications.

The body of research presented in this …

Temperature And Ph Responsive Polyethylenimine Systems As Potential Nonviral Gene Vectors, S. Chad Skidmore

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Modified HPEI was used to determine if the LCST could be controlled by varying multiple variables, including: percent modification, pH, salt solution concentration, and weight percent. Two modifications were done with butylene oxide (Butox) and isobutyryl amide (IBAm). Specifically, 100% (HPEI-Butox1.00)butoxylated and 10% (HPEI-IBAm0.10), 54% (HPEI-IBAm0.54), and 70% (HPEI-IBAm0.70) amidated samples were synthesized. Additionally, HPEI-IBAm0.54 was further modified with hydroxyl ethyl groups (HPEI-IBAm0.54 Eox0.46) and ethyl groups (HPEI-IBAm0.54-Et0.44). The LCSTs of all amidated systems were below body temperature, 37 °C, at pH = 7.4. This indicates an ability of these systems to be used as a vector for gene delivery. …

Novel Synthesis Of Polyhydrogenated Fullerenes, Angela Campo

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Hydrogenated fullerenes are of interest as a starting material in metal fulleride synthesis. By reacting C₆₀H₂ with various metals, alloyed metal fullerides could be produced. To achieve this goal, first a reliable synthesis of C₆₀H₂ must be determined. C₆₀H₂ is difficult to synthesis exclusively; C₆₀H₄ and C₆₀H₆ are also produced. Reduction of C₆₀ with NaBH₄ produced a mixture of products as well as excessive unreacted C₆₀. Attempts to modify this reaction to achieve C₆₀H₂ exclusively were unsuccessful. A …

Small Molecule Caspase Inhibitors Using Isatin And Oxindole Scaffolds And A Combinatorial Approach, Hagar Mahmoud Abdallah

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Quinolyl-valyl-O-methylaspartyl-[2,6-difluorophenoxy]-methyl ketone (Q-VD-OPh) is a next generation broad spectrum caspase inhibitor, the effectiveness and reduced toxicity of which can be partially attributable to the carboxyterminal O-phenoxy group as well as the amino terminal quinolyl groups. We seek to incorporate some of these unique recognition elements onto small molecule derived protease inhibitors with drug like properties. Specifically, heterocyclic scaffolds such as isatins and oxindoles. Thus, isatins bearing electron withdrawing groups on C-5 and 2,6-difluorobenzyl moieties have been prepared by analogy to the well studied N-substituted 5-pyrrololidinylsulfonyl isatins. Moreover, 3-benzylidene oxindole derivatives bearing these structural motifs have also been prepared and their …

Temperature And Frequency Dependent Conduction Mechanisms Within Bulk Carbon Nanotube Materials, John Simmons Bulmer

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The resistance of three types of bulk carbon nanotube (CNT) materials (floating catalyst CNT yarn, forest grown CNT yarn, and super acid spun CNT fiber) was measured from room temperature to 900 C. Fitting the curves to established conduction equations for disordered materials, competing conduction mechanisms pertaining to the material could be determined. Floating catalyst CNT yarn displayed both semiconductive and metallic isotropic behavior with a resistance minimum, similar to the behavior of crystalline graphite. It was found that, at room temperature, the semiconducting contribution-most likely junctions between CNTs-accounted for 99.99% of the overall resistance. The resistance of forest grown …

Ostwald Ripening Of Iron (Fe) Catalyst Nanoparticles On Aluminum Oxide Surfaces (Al2O3) For The Growth Of Carbon Nanotubes, Roberto I. Acosta

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Theoretical models have proposed that the nucleation and growth mechanism of carbon nanotubes (CNTs) has been affected by the catalytic activity of transition metals. The catalyst behavior during growth has been mainly associated as the responsible mechanism for the termination of CNT growth. Although several hypotheses have been developed to explain this mechanism, is still today an unresolved phenomenon. It was recently shown that the Ostwald ripening of iron (Fe) nanoparticles played a dominant role in the termination of CNT growth. The Ostwald ripening mechanism was further investigated as a function of thermal annealing in Hydrogen (H₂) for …

Experimental Comparison Of Acr And Icamrl Magnetic Resonance Imaging Accreditation Protocols, Brock Andrew Prater

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Two primary accrediting bodies exist for magnetic resonance imaging systems: the American College of Radiology (ACR) and the Intersocietal Commission for the Accreditation of Magnetic Resonance Laboratories (ICAMRL), each of which defines specific standards for specific image quality criteria at which MRI images must be produced. An MRI clinic that wishes to show a commitment to image quality may do so by becoming accredited by one of these organizations of their choosing. The limits of these image criteria were compared to demonstrate the standards of each accrediting body. Images were produced that fell well within the standards of both accrediting …