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Geophysical Reconnaissance Of Karst Features Associated With Sinkholes On The Antioch University Campus In Yellow Springs, Ohio: Western Area, Brent Matthew Zerkel Jan 2007

Geophysical Reconnaissance Of Karst Features Associated With Sinkholes On The Antioch University Campus In Yellow Springs, Ohio: Western Area, Brent Matthew Zerkel

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Antioch University is located in Yellow Springs, OH. This study was conducted on the Antioch University Campus in the commons area and is concentrated on the area west of the easternmost sinkhole. The primary purpose of this study is to locate and identify buried anomalous karst features, such as joints and collapses that may be hazardous to nearby buildings on the Antioch University Campus. The secondary purposes of this study are to identify remaining features in the geophysical data that may be related to manmade structures, and to identify areas for future studies. It is known that an 8-inch steel …

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Seasonal Variation In The Redox Zones And Biogeochemical Processes Within The Constructed Wetland, Yussuf Mohamud Jan 2007

Seasonal Variation In The Redox Zones And Biogeochemical Processes Within The Constructed Wetland, Yussuf Mohamud

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This research investigation focuses on the vertical distribution of dissolved inorganic species in the pore-water affected by redox processes and seasonal changes within a small constructed wetland located at the Wright-Patterson Air Force Base. This is a follow up study to an earlier investigation (Lach, 2004) at this site in 2003. Water samples were collected from influent, effluent and three layers of the constructed wetland through a network of nested piezometers in the vertical flow wetland from June 2005 to June 2006. Onsite analysis of temperature, pH and conductivity were carried out onsite. Major anions and cations were measured by …

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Modifiable Poly(Arylene Ether)S And Hyperbranched Poly(Esters), Brian Scott Werry Jan 2007

Modifiable Poly(Arylene Ether)S And Hyperbranched Poly(Esters), Brian Scott Werry

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Two different polymer systems have been studied in regards to their potential for functionalization to introduce new characteristics to the polymer. The first polymer system is a poly(arylene ether) with a truly pendant sulfone group from the monomer 3,5-difluorodiphenylsulfone. The work entails incorporating a bromine moiety onto the monomer for the versatile ability to bring in functional groups prior to or post the polymerization. The introduction of bromine onto the pendant ring had the best results from electrophilic bromine addition using N-bromosuccinimide in a mixture of sulfuric acid and acetic acid (80:20) yielding 76% of the desired material. Incorporation of …

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Laser Induced Fluorescence Spectroscopy Of Molecular Bromine: Observations Of Emission To High Vibrational Levels In The Ground (X) State, David Jonathan Postell Jan 2007

Laser Induced Fluorescence Spectroscopy Of Molecular Bromine: Observations Of Emission To High Vibrational Levels In The Ground (X) State, David Jonathan Postell

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The Laser Induced Fluorescence spectrum of the B - X system of molecular bromine was recorded using a Red and Near Infrared sensitive PMT coupled to a scanning monochromator. A 543 nm HeNe laser was used to excite three resonances. Assignment of those resonances was made. A line narrowed Nd:YAG laser was used to excite eight fluorescence progressions, six from the (79,81) bromine isotopomer and one each from the (79,79) bromine and (81,81) bromine isotopomers. Analysis of the visible bands helped determine the resonances excited by the Nd:YAG laser. Fluorescence in the near infrared region, 9500 - 14000 angstroms, was …

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Distribution Of Ground-Layer Plant Species In A Fragmented Landscape In The Corozal District, Belize, Central America, Divan Catzim Jan 2007

Distribution Of Ground-Layer Plant Species In A Fragmented Landscape In The Corozal District, Belize, Central America, Divan Catzim

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In this study, I specifically looked at three major issues regarding 36 target plant species in a fragmented landscape in the Corozal district, Belize: 1) Determine woodlot characteristics that tend to favor the target species. 2) Determine plant characteristics that tend to favor the target species. 3) Determine whether age and size of a woodlot favors the presence of the target species. The study area was divided into three areas and each area had woodlots varying in sizes and ages. 36 plant species were sampled in all woodlots upon which woodlot characteristics and species characteristics were associated with the number …

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Comparative Investigation Of Dosimetric Tools In Imrt, Aaron Nicholas Garcia Jan 2007

Comparative Investigation Of Dosimetric Tools In Imrt, Aaron Nicholas Garcia

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Verification of the isodose distribution delivered to the planned tumor volume is required for quality assurance in the clinic. Verification in this context means ensuring that the actual dose delivered to a volume matches the dose that a computerized planning system intended that volume to receive. The computerized planning is performed by a Computerized Medical Systems (CMS) Intensity Modulated Radiation Therapy (IMRT) plan. Two methods of measuring the delivered dose are film dosimetry and diode dosimetry. This project will compare the relative isodose distribution profiles of film dosimetry and MapCheck (Sun Nuclear Corporation, a diode-based dosimetry system) to the relative …

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Summaritive Digest For Large Document Repositories With Application To E-Rulemaking, Lijun Chen Jan 2007

Summaritive Digest For Large Document Repositories With Application To E-Rulemaking, Lijun Chen

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Large document repositories need to be organized and summarized to make them more accessible and understandable. Such needs exist in many applications, including web search, e-rulemaking (electronic rulemaking) and document archiving. Even though much has been done in the areas of document clustering and summarization, there are still many new challenges and issues that need to be addressed as the repositories become larger, more prevalent and dynamic. In this dissertation, we investigate more informative ways to organize and summarize large document repositories, especially e-rulemaking feedback repositories (ERFRs), so that the large repositories can be managed and digested more efficiently and …

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Analysis Of Sex Reversal And Tra-2 Nucleotide Variation In Tropical And Temperate Clades Of Caenorhabditis Briggsae, Irene Zelepuhin Jan 2007

Analysis Of Sex Reversal And Tra-2 Nucleotide Variation In Tropical And Temperate Clades Of Caenorhabditis Briggsae, Irene Zelepuhin

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Reproductive isolation results when members of the same species cannot reproduce due to either prezygotic or postzygotic mechanisms, therefore restricting gene flow between populations. A leading model describing reproductive isolation developed by J.B. Haldane (1922) states, "When offspring from two different animal species have one sex that is rare, absent, or sterile, that sex is the heterozygous (XO) or heterogametic (XY) sex". Haldane's rule is illustrated among various animal taxa regardless of which sex is heterogametic. To date, Caenorhabditis mating tests are the only example of Haldane's rule that is caused by sexual transformation and not gender specific lethality or …

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Hydrophobically Modified Polyethyleneimines And Ethoxylated Polyethyleneimines, Michael Joseph Simons Jan 2007

Hydrophobically Modified Polyethyleneimines And Ethoxylated Polyethyleneimines, Michael Joseph Simons

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The modification of the commercially available polymers polyethyleneimines and ethoxylated polyethyleneimines took place with approximately a 3-10% alkylbromide modification followed by, in the case of the polyethyleneimines, a 2-hydroxypropyl modification, using propylene oxide, on the order of 65-70%. The objective was to increase the hydrophobicity of the polymer while keeping the cloud point above 60°C. Another approach taken was to form hydrophobic ethers from ethoxylated polyethyleneimine. We also added a 2-hydroxy ethyl group to a hexylated polyethyleneimine avoiding the use of ethylene oxide or drying EPI.

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Tailoring Branching For Poly (Arylene Ether)S Via Reactivity Ratio Controlled Polymerizations, Amanda Ike Jan 2007

Tailoring Branching For Poly (Arylene Ether)S Via Reactivity Ratio Controlled Polymerizations, Amanda Ike

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The ability to control physical and mechanical properties of polymer systems has become an important aspect of polymer science. In order to tailor the branching in polymer systems, an understanding into the reactivity of the electrophilic sites in the monomer is important. Kinetic methods have been explored in order to determine the reactivity of monomers in preparing poly(arylene ether)s and to predict the degree of branching that will occur in a polymer of this kind. The reactivity of AB2 sulfones and phosphine oxides was explored, along with the reactivity of ABB'B'' sulfones. NMR spectroscopy was used as a probe into …

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Fabrication Of Silver Nanoparticles By Solution Phase Method And Physical Characterization Of Their Arrays, Jaesung Oh Jan 2007

Fabrication Of Silver Nanoparticles By Solution Phase Method And Physical Characterization Of Their Arrays, Jaesung Oh

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Synthesis of silver nanostructures has been an active research area for many decades because of their importance in biological sensing, imaging, electronics, optoelectronics and catalysis. In particular, much effort has been devoted to the controlled synthesis of silver nanowires because of their potential use as interconnects or active components in fabricating nanoscale devices. The solution phase method is used here to form Ag nanoparticles by reducing silver nitrate with ethylene glycol heated to 160°C. The additional presence of polyvinyl pyrrolidone plays a role of stabilizer to prevent an agglomeration and/or a capping agent to produce highly anisotropic nanowires. Silver nanoparticles …

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Impact Of Land Use On Water Quality In The Indian Lake Watershed: An Integrated Geographic Information Systems Approach, Michael Belke Jan 2007

Impact Of Land Use On Water Quality In The Indian Lake Watershed: An Integrated Geographic Information Systems Approach, Michael Belke

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Geology and land use and land cover are the most important factors that influence water quality. The purpose of this study is to investigate how these factors operate in a rural watershed. Specifically, this thesis tests the feasibility of a proposed formula to relate how land use affects surface water quality and to infer hydrogeochemical reactions that control water chemistry through hydrogeochemical speciation and mineral stability relationships. Samples were collected from Indian Lake and its watershed in West-Central Ohio. BASINS, produced by the USEPA, was then used to delineate sub-watersheds and find the land use areas of these watersheds. The …

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Development Of An Intelligent Autonomous Coffee Maker, Nicholas J. Vanderpool Jan 2007

Development Of An Intelligent Autonomous Coffee Maker, Nicholas J. Vanderpool

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Using Intelligent Control Methodology Home coffee machines have improved over time with the addition of features such as self-activating timers and crude temperature controlled heating elements. However, home coffee brewer development has stagnated and has yet to achieve full automation status. Present coffee machines leave the user burdened with the mundane and messy task of preparing the coffee maker every time. Also, should the user decide to prepare less than an entire pot, he/she must estimate the correct amount of water and coffee to add. This can lead to a weak or strong brew, giving undesirable results. In order to …

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Analysis Of Very Large Scale Image Data Using Out-Of-Core Technique And Automated 3d Reconstruction Using Calibrated Images, Chandrashekara Hassan Raju Jan 2007

Analysis Of Very Large Scale Image Data Using Out-Of-Core Technique And Automated 3d Reconstruction Using Calibrated Images, Chandrashekara Hassan Raju

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Analysis of large scale volumetric data sets is very important from the researcher's and technological point of view as it helps in understanding and analyzing the original data. For example, when analyzing volumetric images from cast arteries of pigs, it is essential to apply a suitable segmentation in order to retrieve morphometric data from the scanned image. Due to improved scanning technology, such as MicroCT, these scanned images can get as large as several gigabytes in size. In order to analyze such large scale data sets on common desktop computers is a challenge due to limited main memory. By using …

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Fpga Based Hardware Implementation Of Advanced Encryption Standard, Sowrirajan Sampath Jan 2007

Fpga Based Hardware Implementation Of Advanced Encryption Standard, Sowrirajan Sampath

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On October, 2, 2000, The National Institute of Standards and Technology (NIST) announced Rijndael as the new Advanced Encryption Standard (AES). The other competing algorithms were Mars, RC6, Serpent and Two-fish. The Predecessor to the AES was Data Encryption Standard (DES) which is considered to be insecure because of its vulnerability to brute force attacks. DES was a standard from 1977 and stayed until the mid 1990's. However, by the mid 1990s, it was clear that the DES's 56-bit key was no longer big enough to prevent attacks mounted on contemporary computers, which were thousands of times more powerful than …

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Skin And Proximity Effects In Two Parallel Plates, Hamdi Eltayib Abdelbagi Jan 2007

Skin And Proximity Effects In Two Parallel Plates, Hamdi Eltayib Abdelbagi

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Time varying currents within winding and core conductors induce magnetic fields. When more than one conductor is present the resultant magnetic field can be found by adding the individual magnetic fields by superposition. The resultant magnetic field in turn induces eddy currents within each electrical component within the vicinity of the resultant magnetic field. Eddy currents flow in the opposite direction of the primary current and increase the resistance by reducing the area in which the primary current has to travel. Eddy currents also reduce the effectiveness of the conductors to conductor high frequency currents. Skin and proximity effects were …

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Bezier Surface Generation Of The Patella, Dale A. Patrick Jan 2007

Bezier Surface Generation Of The Patella, Dale A. Patrick

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A method to generate control points for a given collection of data points is developed. The shape characteristics of the patella are used as a case study. The developed computer graphic techniques are demonstrated using the given data of the 3-d patella model. Generation of curved surfaces in drafting has evolved over the years from draftsman who used tools such as French curves to today's drafting being well served by being able to apply numerical analysis on the ever increasing capabilities of computer. As an everyday observed example, nature very rarely produces two shapes that are equal to another. It …

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Polarization Reversal In Potassium Titanyl Phosphate, William D. Mitchell Jan 2007

Polarization Reversal In Potassium Titanyl Phosphate, William D. Mitchell

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Polarization reversal in both hydrothermal and flux grown potassium titanyl phosphate was studied using square pulses at room temperature from 1600 V/mm to 5000 V/mm. Maximum switching current and inverse switching time data is compared to the ferroelectric polarization reversal model developed by Fatuzzo and Merz in the last century. Room temperature calculation of spontaneous polarization is reported and compared to that of potassium titanyl phosphate in the literature.

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Simple Descriptors For Modeling The Solubility Of Gases, Alcohols, And Halogenated Hydrocarbons In Water, Sule Sidigu Jan 2007

Simple Descriptors For Modeling The Solubility Of Gases, Alcohols, And Halogenated Hydrocarbons In Water, Sule Sidigu

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The Statmost, QSARIS, Excel, and SAS programs were used to model the solubility of gases, alcohols, and halogenated hydrocarbons in water using simple physical and topological descriptors. The alcohols were well-modeled using measures of the number of carbons, terminal methyls, and steric hindrance about the hydroxyl group. Molecular mass, boiling point, and critical volume or critical pressure were the best descriptors for the halogenated hydrocarbons. Critical pressure was the most applicable single descriptor for the gases. Molecular mass and boiling point also yielded good results for the gases and halogenated hydrocarbons when regressed together.

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Gpu-Assisted Rendering Of Large Tree-Shaped Data Sets, Pallavi Ramachandra Mangalvedkar Jan 2007

Gpu-Assisted Rendering Of Large Tree-Shaped Data Sets, Pallavi Ramachandra Mangalvedkar

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Due to their complexity, medical data sets can easily comprise of several gigabytes in size. For example, geometric representations of a coronary arterial tree spanning vessels from the large proximal coronary arteries down to the capillary level consist of 6 gigabytes or more of geometry data, depending on the accuracy of the geometric representation. Visualization of such large data sets using the CPU alone can be inefficient and time consuming since they require special out-of-core techniques due to the size of the data set. The usage of the GPU can help render such data sets faster compared to CPU-based implementations …

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Design Of A Controller To Control Light Level In A Commercial Office, Saeid Javidbakht Jan 2007

Design Of A Controller To Control Light Level In A Commercial Office, Saeid Javidbakht

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Proper amount of light in a business office is important for health and productivity of the employees. On a sunny day, there may be more than enough light entering the office from outside to carry out the necessary tasks. Presently, the main source of light in most offices is the fluorescent lamp. Thus, It is possible to save energy by dimming the fluorescent lamp. Dimming of the fluorescent lamp is possible by changing the frequency of the sinusoidal voltage or current. Hence, there is a need of a control system to adjust the light from the fixtures based on the …

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Formation Of A Sydno[3,4- A]Indolone And Reactions Thereof, Ryan Christopher Vikan Jan 2007

Formation Of A Sydno[3,4- A]Indolone And Reactions Thereof, Ryan Christopher Vikan

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In the present work, a synthetic route to the formation of a sydno[3,4- a]indolone was explored in the hope of attaining the first example of a fused-ring sydnone with an sp2-hybridized bridge. Formation of this product and exploration of its chemical behavior was anticipated to be of particular interest to the formation of NO-releasing prodrugs. A direct synthetic pathway to yield the target sydnoindolone starting from 3-(2-methoxycarbonylphenyl)sydnone and reaction with a base was proposed and explored. Attempted formation and isolation of the target sydnoindolone proved impossible under a variety of different conditions, undoubtedly due to the instability of this …

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Design And Implementation Of Timeline Application For News Documents, Mastan Vali Shaik Jan 2007

Design And Implementation Of Timeline Application For News Documents, Mastan Vali Shaik

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The growing News document archive emphasizes the need for efficient techniques to retrieve and visualize its content. We present a timeline based graphical interface for this purpose. The timeline is a graph of number of documents supporting association between entity (event, country, person, etc) etc and event (entity, country, person, etc) with respect to dates. The query is formulated based on entity, event, country, and person metadata extracted from the text of the News documents by analyzing the documents using proprietary name-entity recognizers. The timeline also provides a means to index and access relevant documents. Associations inferred on the basis …

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Fuel Flow Control Issue In Jet Engines: An Evolvable Hardware Approach, Kshitij S. Deshpande Jan 2007

Fuel Flow Control Issue In Jet Engines: An Evolvable Hardware Approach, Kshitij S. Deshpande

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Dealing with unexpected dynamic loads in Jet and Turbine engines have always been a matter of concern and an active area of research. This thesis is an initial attempt to apply Evolvable Hardware methods for augmenting classical control methods in a generic turbine engine model. In this work, the Air Force Research Laboratory Generic Turbine Engine Model was converted into C and interfaced with a simulation of a EH VLSI control chip currently under development. The simulated EH device was allowed to evolve to augment the simulated engine's standard FADEC controller so that the whole system could tolerate unexpected, large …

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Fabrication And Testing Of Scaffolds For Cell Growth From Ionic Liquid Solubilized Fibroin, Maneesh Kumar Gupta Jan 2007

Fabrication And Testing Of Scaffolds For Cell Growth From Ionic Liquid Solubilized Fibroin, Maneesh Kumar Gupta

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The advent of tissue engineering has spurred research into developing materials to act as scaffolds for tissue growth. These scaffolds require materials capable of mimicking the in vivo conditions so that tissues can be grown effectively in vitro. Silk is an attractive biomaterial for use in tissue engineering applications because of its slow degradation, excellent mechanical properties, and biocompatibility. The major objective of the research in this thesis is to demonstrate a simple method to cast films directly from silk fibroin dissolved in an ionic liquid. The films cast from the silk ionic liquid solution were found to support normal …

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High Spurious-Free Dynamic Range Digital Wideband Receiver For Multiple Signal Detection And Tracking, Vivek Sarathy Jan 2007

High Spurious-Free Dynamic Range Digital Wideband Receiver For Multiple Signal Detection And Tracking, Vivek Sarathy

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The advent of field-programmable gate array (FPGA) has provided an excellent platform to market prototyping of full receiver-on-chip designs in a short time. The design of multi-tone wideband receiver has always been a challenge because of the difficulty to detect weak signals in the presence of noise in the frequency spectrum and also the presence of general spurs generated by the receiver. In this research, architecture for a FPGA-based 2.56-GSPS digital wideband receiver with multi-tone signal detection and tracking is designed to demonstrate the capability of replacing more expensive analog components into their cheaper digital design counterparts. Novel hardware implementations …

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Comparative Microarray Data Mining, Shihong Mao Jan 2007

Comparative Microarray Data Mining, Shihong Mao

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As a revolutionary technology, microarrays have great potential to provide genome-wide patterns of gene expression, to make accurate medical diagnosis, and to explore genetic causes underlying diseases. It is commonly believed that suitable analysis of microarray datasets can lead to achieve the above goals. While much has been done in microarray data mining, few previous studies, if any, focused on multiple datasets at the comparative level. This dissertation aims to fill this gap by developing tools and methods for set-based comparative microarray data mining. Specifically, we mine highly differentiative gene groups (HDGGs) from given datasets/classes, evaluate the concordance of datasets …

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Particle Based Plasma Simulation For An Ion Engine Discharge Chamber, Sudhakar Mahalingam Jan 2007

Particle Based Plasma Simulation For An Ion Engine Discharge Chamber, Sudhakar Mahalingam

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Design of the next generation of ion engines can benefit from detailed computer simulations of the plasma in the discharge chamber. In this work a complete particle based approach has been taken to model the discharge chamber plasma.This is the first time that simplifying continuum assumptions on the particle motion have not been made in a discharge chamber model. Because of the long mean free paths of the particles in the discharge chamber continuum models are questionable. The PIC-MCC model developed in this work tracks following particles: neutrals, singly charged ions, doubly charged ions, secondary electrons, and primary electrons. The …

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A Hybrid Approach To Retrieving Web Documents And Semantic Web Data, Trivikram Immaneni Jan 2007

A Hybrid Approach To Retrieving Web Documents And Semantic Web Data, Trivikram Immaneni

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The Semantic Web has been evolving into a property-linked web of RDF data, conceptually divorced from (but physically housed in) the World Wide Web of hyperlinked documents. Data Retrieval techniques are typically used to retrieve data from the Semantic Web while Information Retrieval techniques are used to retrieve documents from the Hypertext Web. Conceptually unifying the two webs enables the exploitation of their interconnections resulting in benefits to both data and document retrieval. Towards this end, we present the Unified Web model that integrates the two webs and formalizes the structure and the semantics of their interconnections. We present a …

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Wsu Research News, Winter 2006, Office Of Research And Sponsored Programs, Wright State University Dec 2006

Wsu Research News, Winter 2006, Office Of Research And Sponsored Programs, Wright State University

WSU Research News

A twelve page newsletter of the WSU Research News. The WSU Research News was published monthly beginning in June of 1968 and issued by the Office of Research Development. This newsletter was created to provide information to the WSU faculty about the availability of outside funds for research and educational programs, new developments that may affect availability of funds, and general information on research and educational activities at Wright State University.

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