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The Effect Of Process Variables On Microstructure In Laser-Deposited Materials, Srikanth Bontha

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The ability to predict and control microstructure in laser deposition processes requires an understanding of the thermal conditions at the onset of solidification. The focus of this work is the development of thermal process maps relating solidification cooling rate and thermal gradient (the key parameters controlling microstructure) to laser deposition process variables (laser power and velocity). The approach employs the well-known Rosenthal solution for a moving point heat source traversing an infinite substrate. Cooling rates and thermal gradients at the onset of solidification are numerically extracted from the Rosenthal solution throughout the depth of the melt pool, and dimensionless process …

A Formal Language Approach For Detecting Texture Paths And Patterns In Images, Prithviraj S. Patil

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This Master thesis considers the use of formal languages representation for image processing, especially texture patterns and determining texture paths in them. The texture paths are detected and extracted by using image processing techniques, such as image segmentation to isolate regions of interest, and then the extraction of repeating textures. The detection of the texture blocks is obtained by recursively using 27 X 27, 9 X 9, and 3 X 3 windows. Predefined repeating texture patterns are also searched for in each of the sets. For each set of texture blocks with similar or same characteristics, curve fitting techniques are …

Exploration Of Iron And Cobalt Core-Shell Nanoparticles Via Thermal And Microwave Polyol Synthesis, Hope M. Klukovich

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Thermal and microwave polyol methods were investigated in the synthesis of various iron and cobalt core-shell nanoparticles. The reaction involved 1 mmol of an Fe⁺² or Co⁺² salt, bis-acetylacetanato [(Acac)2] iron (II), cobalt (Acac)2 or iron (II) acetate along with 1 mmol of a surfactant capping agent. The salt was reduced with 2 mmol of a 1,2 diol. When 1,2-hexadecanediol solid was used as a reducing agent, it was dissolved along with the metal salt and capping agent in octyl ether. When 1,2-hexanediol liquid was used as the reducing agent, it was also the solvent, and octyl ether …

Investigation Into The Behavior Of Bolted Joints, Steven M. Page

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Models to capture the physics of jointed structures have been proposed for over 40 years. These models approximate the behavior of the joint under carefully developed operating conditions. When these conditions change, the model has to be changed. Recent developments in numeric codes like finite elements have created interest in incorporating joint models into the design process but joint models need to represent the joined structure over a broader operating range. This work investigates the dynamic response of a structure with a joint. Isolation of a few dominant effects may give way to a model able to capture a broader …

Feasibility Analysis Of The Strontium Ratio Obtained From Pennsylvanian Chondricthian Dentary, Cullen John Erbacher

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This research was undertaken to determine the amount of time between transgressive and regressive sequences. One of the methods used to determine the amount of missing time in an unconformity is the 87Sr / 86Sr ratio. The 87Sr / 86Sr ratio will be high around brackish and freshwater environments while it will be lower in open marine conditions. Limestones and their constituent parts are susceptible to diagenetic processes that can contaminate or obliterate isotope values contained within the rocks. The purpose of this research was to discover if reliable isotope information could be pulled from Pennsylvanian aged shark teeth. Nine …

Simulation And Analysis Of Rfid Localization Algorithms, Zubin Shah

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Radio frequency identification (RFID) based localization systems provide a unique approach to localize mobile entities equipped with RFID readers or tagged with RFID tags. UHF RFID systems using passive tags are a good choice considering their cost, reading range, and reliability. With global acceptance and deployment of UHF RFID systems using passive tags for tracking and identification, virtually everything around us can be tagged with small and low-cost passive RFID tags. This thesis describes a Monte Carlo Localization based algorithm to localize a mobile RFID reader within a tagged environment. A software tool is developed to validate this localization process, …

Phenotypic Characterization Of Escherichia Coli Strains Taken From Human Intestinal And Urinary Tracts, Kruthi Murthy

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Escherichia coli (E. coli) is a gram negative bacterium commonly found as a commensal in the intestinal tract of humans and other warm blooded animals. The commensal strains of E. coli are non-pathogenic and do not cause an infection in the host. However, some strains of E. coli are pathogenic and can cause several diseases in humans that include neonatal meningitis, intestinal infections and urinary tract infections. Almost 80-85% of the uncomplicated urinary tract infections are caused by uropathogenic E. coli. Our project involved the characterization of 12 strains of E. coli, isolated from humans in health and disease. These …

Models Of Disordered Media And Predictions Of Associated Hydraulic Conductivity, L. Aaron Blank Jr.

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In the late 20th century there was a spill of Technetium in eastern Washington State at the US Department of Energy Hanford site. Resulting contamination of water supplies would raise serious health issues for local residents. Therefore, the ability to predict how these contaminants move through the soil is of great interest. The main contribution to contaminant transport arises from being carried along by flowing water. An important control on the movement of the water through the medium is the hydraulic conductivity, K, which defines the ease of water flow for a given pressure difference (analogous to the electrical conductivity). …

Development Of An Audio Visual Tool For Medical Training At Kennedy Space Center, Rimawi, Nidal El

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As part of an effort to improve efficiency of space-flight medical support at Kennedy Space Center, a training video was created to replace a series of lectures given before a launch or landing of the Space Shuttle. The video was designed to familiarize volunteer physicians from around the country with the specific emergency response protocols for a Space Shuttle launch or landing emergency at Kennedy Space Center. The methods used were consistent with standard film making techniques as outlined in several film making texts. The Production was divided into three phases; A pre-production phase wherein the research, screenwriting and production …

Specification For Visual Requirements Of Work-Centered Software Systems, James Robert Knapp

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Work-centered software systems function as inherent work-aiding systems. Based on the design concept for a work-centered support system (WCSS), these software systems support user tasks and goals through both direct and indirect aiding methods within the interface client. In order to ensure the coherent development and delivery of work-centered software products, WCSS visual interface requirements must be specified in order to capture the cognitive and work-aiding aspects of the user interface design. Without the ability to specify such original requirements, the probability of creating an accurate and effective work-centered software system is significantly reduced. A new visual requirements specification language …

Coronary Heart Disease Risk Stratification In Full-Time Miami Valley Hospital Employees, Vicki K. Streng

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Heart disease is the number one killer in the United States (American Heart Association, 2005). The purpose of this study was to demonstrate the results of a twelve-week exercise program on coronary heart disease risk factors in full-time hospital employees. Methods: The participants were given cardiovascular, weight training, and flexibility recommendations to follow during a twelve-week period. The main heart disease risk factors measured before and after the completion of the exercise program were blood pressure, total cholesterol, HDL-cholesterol, and body mass index. The information was put into the Framingham Heart Score to estimate the participants’ 10-year risk of developing …

Determining The Effect Of Substitutions At Alanine 47 In Synechococcus Pcc6301 Ribulose-1,5-Bisphosphate Carboxylase/Oxygenase (Rubisco), Christopher R. Salyer

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Mutant screening and genetic selection in various organisms have shown that residues far from the active site of ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO) can influence catalytic efficiency and CO2/O2 specificity. Because RubisCO catalyzes the rate-limiting step of photosynthesis, further study of these sites distant from the primary reaction center may provide the necessary information for engineering an increase in primary productivity of crop plants. In a previously described system of random mutagenesis and bioselection (Smith, 2002), the RubisCO genes from the cyanobacterium Synechococcus PCC6301, were randomly mutated and introduced into the photosynthetic bacterium Rhodobacter capsulatus. An A47T substitution resulted in a very …

Robust Estimation Of Reliability In The Presence Of Multiple Failure Modes, Phani R. Adduri

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In structural design, every component or system needs to be tested to ascertain that it satisfies the desired safety levels. Due to the uncertainties associated with the operating conditions, design parameters, and material systems, this task becomes complex and expensive. Typically these uncertainties are defined using random, interval or fuzzy variables, depending on the information available. Analyzing components or systems in the presence of these different forms of uncertainty increases the computational cost considerably due to the iterative nature of these algorithms. Therefore, one of the objectives of this research was to develop methodologies that can efficiently handle multiple forms …

Computational Study Of Ring-Cusp Magnet Configurations That Provide Maximum Electron Confinement, Taiwo A. Ogunjobi

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Enhancing the confinement of primary electrons within the plasma in a discharge chamber of an ion thruster improves plasma ionization and consequently the thruster's performance. This work computationally calculates the location, position, and orientation of the permanent magnets that provide a ring-cusp magnetic field that maximizes electron confinement in an axi-symmetric cylindrical aluminum-wall discharge chamber. Small samarium cobalt magnets are circumferentially arranged in a ring around the front, side, or back wall of the chamber. The generated ring-cusp magnetic field for any specified magnet configuration is calculated using MAXWELL2D, a two dimensional electromagnetic field simulation computer code. For various magnet …

Anti-System Parties:Policy Choices For Democracies A Study Of India's Bharatiya Janata Party And Austria's Freedom Party, Kristina M. Teater

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In the decades following WWII, countries across the globe witnessed the rise of anti-system parties. Political scientists have attributed their success to economic conditions, electoral systems, party systems and the electorate’s disaffection with mainstream parties. The analysis also suggests the influence of global factors. While the causes for success have been examined, effective policy choices for democracies have not been equally explored. This study makes the argument that by including anti-system parties in government, states are able to lessen the threat they pose to democracy. The analysis of India’s Bharatiya Janata Party and Austria’s Freedom party suggest that anti-system parties …

Pyrrole Carboxamides As Potential Carbonic Anhydrase Inhibitors, Nishrin Ismailbhai Marketwala

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Carbonic anhydrases (CAs) are metalloenzymes that catalyze the reversible interconversion of CO2 and bicarbonate. We recently initiated a screen of a broad range of indoles and pyrroles possessing acyl-, carboxyl-, amido-, sulfonyl-, sulfamyl- and oxime- functionalities as potential inhibitors of á-CA II isozyme. As slight inhibition was observed in the case of 2-carboxamido-1-(phenylsulfonyl)pyrrole, and aware that pyrrole carboxamide derived sulfonamides had been previously demonstrated to possess CA inhibition, we sought to prepare a series of 1-(phenylsulfonyl)pyrrole-2-carboxamides but lacking a sulfonamide moiety to ascertain if the activity in our case might be due to a hitherto unrecognized pyrrole pharmacophore. To this …

Geostatistical Characterization Of Heterogeneity In The Aberjona River Aquifer, Woburn, Massachusetts, James Ralph Damico

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Ground water flow and contaminant transport patterns are largely controlled by the distribution of high- and low-permeability sediments. Therefore, an accurate description of the aquifer architecture is paramount to producing a representative ground water model. Models of contaminant fate and transport in the aquifer near Woburn, Massachusetts, have previously been created by others using a deterministic approach. As a complement to these prior studies, the proportions, geometry, and juxtaposition of the different lithofacies of the aquifer were statistically characterized for developing stochastic models for the aquifer system. The descriptions of lithology from boreholes were separated into eleven categories based primarily …

Methodology For Quantifying Biomechanical Bone Movement Of Transtibial Amputations, Johanna C. Bell

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A controversy has long existed about an alternate below knee amputation procedure that may be more beneficial than the traditional transtibial amputation. The proponents of this alternate procedure that stabilizes the distal tibia and fibula claim it reduces excessive movement of the fibula relative to the tibia that occurs with common movements, such as walking. The purpose of this study is to develop a methodology for quantifying excessive movement of the fibula bone relative to the tibia bone in traditional below the knee amputations. The methodology will measure the movement and rotation of the fibula relative to the tibia. These …

A Field Programmable Gate Array Architecture For Two-Dimensional Partial Reconfiguration, Fei Wang

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Reconfigurable machines can accelerate many applications by adapting to their needs through hardware reconfiguration. Partial reconfiguration allows the reconfiguration of a portion of a chip while the rest of the chip is busy working on tasks. Operating system models have been proposed for partially reconfigurable machines to handle the scheduling and placement of tasks. They are called OS4RC in this dissertation. The main goal of this research is to address some problems that come from the gap between OS4RC and existing chip architectures and the gap between OS4RC models and practical applications. Some existing OS4RC models are based on an …

Kinetics And Passive Protection Efficacy Induced By Purified Ava Human Immunoglobulin G In Rabbits Against A Bacillus Anthracis Aerosol Challenge, Jennifer Lee Plahovinsak

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The present study was conducted to determine the half-life, assess the toxicity, and passive protection efficacy of purified immunoglobulin G (IgG) from Anthrax Vaccine Adsorbed (AVA) vaccinated human donors. Half-life determinations were calculated from the reportable values obtained using the anti-PA ELISA assay and the Centers for Disease Control's (CDC) "ELISA for Windows" software. For toxicity evaluations animals were observed clinical for one hour post administration and for 14-days post-treatment. The protection efficacy was determined based upon the mortality results from a lethal Bacillus anthracis aerosol challenge. While no protection was achieved in this delayed exposure scenario, the study yielded …

Active Regulation Of Speed During A Simulated Low-Altitude Flight Task: Altitude Matters!, April M. Bennett

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This study examined active regulation of speed during a low-altitude flight task as a function of global optical flow rate, speed, and the presence or absence of a concurrent altitude disturbance. The results showed that altitude clearly had an impact on speed control; specifically, control of speed was much more difficult when altitude disturbances were present. Even in the no altitude disturbance conditions, performance tended to be best at lower altitudes. Consistent with previous research, the results suggest that speed and altitude changes have additive effects on speed judgments. This is inconsistent with the simple global optical flow rate hypothesis …

Topology Optimization Of Engine Exhaust-Washed Structures, Mark A. Haney

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Aircraft structure subjected to elevated temperature and acoustic loading present a challenging design environment. Thermal stress in a structural component has typically been alleviated by allowing thermal expansion. However, very little work has been done which directly addresses the situation where such a prescription is not possible. When a structural component has failed due to thermally-induced tensile stresses, the answer to the question of how best to stiffen the structure is far from trivial. In this work, we demonstrate that conventional stiffening techniques, for example, those which add material to the thickness of a failing panel, may actually increase the …

Multi-Attribute Optimization Based On Conjoint Analysis, Hemanth K. Amarchinta

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Over the last thirty years, there were tremendous advances in multidisciplinary design optimization in reducing computational cost, developing algorithms for efficient sensitivity analysis in reaching an optimum. Most of these efforts assumed a single objective (attribute) function and a multitude of constraints. Very little work has been done in including the designer's preferences as part of the optimization scheme and in addressing the ability to handle multiple attributes simultaneously. This need to develop a systematic method for including designer's preferences is the main focus of this research work. The concept of modeling preferences among multi-attribute alternatives is prevalent in consumer …

Using In-Situ Error Tracking For Mode Selection In Proper Orthogonal Decomposition Reduced Order Modelling, Michael Richard Maddux

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Proper Orthogonal Decomposition (POD) provides a method of analyzing data and/or creating a Reduced Order Model (ROM). In this thesis, POD is used to create a ROM comprised of basis functions onto which the governing equations of a Computational Fluid Dynamics (CFD) problem are projected via Galerkin's method. The model is of reduced order since the basis functions span a space smaller than the space from which they were created. A full order simulation called the training period is conducted first to obtain data to be used for creating the ROM using POD. The dominant characteristics are extracted from the …

The Modeling Of Solubility, Frank Christopher Campanell

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In this work the solubilities of gases in liquids and liquids in liquids were modeled using both physical properties and topological descriptors of the solutes. Quantitative structure-activity relationship (QSAR) methods were employed to create single-linear regression (SLR) and multiple-linear regression (MLR) models of the solubilities. Factor analysis was employed to determine the number of significant factors present in the solubilities. The solubilities of monoalcohols in water, halogenated alkanes in water, gases in water, gases in alkanes, and gases in alcohols were examined and modeled.

System Analysis And Rf-Floodlight Exploitation Of Short-Range Gotcha Repeaters, Jose A. Montes De Oca

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Emerging wide-area synthetic aperture radar (SAR) system concepts call for a single data collection platform to orbit a large ( e.g., 20-km) spot at a nominal range of 40-km. The large standoff distance and desire for fine resolution, coupled with a need for persistent real-time sensing, pose a significant challenge in terms of clutter-to-noise ratio (CNR) performance and data processing. Increased CNR and reduced processing load can be achieved by decreasing the range of the SAR system and the size of the area of interest. Employing multiple cooperating SAR systems allows the same overall coverage area to be maintained …

Interactive Effects Of Feedback Type And Feedback Propensities On Task Performance, Kristin M. Delgado

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The purpose of the present study was to examine the effects of feedback types (i.e., outcome, process, and task feedback), feedback propensities, and their interactions on task performance in an attempt to determine, first, which types of feedback produced better task performance and, second, how feedback propensities influenced relationships between feedback type and performance. Process feedback and task feedback were expected to interact in their effects on task performance. In addition, I predicted that external feedback propensity would moderate the effects of process feedback on performance and initial task performance would moderate the effects of internal feedback propensity on task …

Review Of Yellow Sky, Michael Adams

Publications and Research

Review of William Wellman's 1948 Western, inspired by Shakespeare's The Tempest.

Review Of I Wake Up Screaming, Michael Adams

Publications and Research

Review of H. Bruce Humberstone's I Wake Up Screaming: http://www.media-party.com/discland/2006/07/i-wake-up-screaming.html

Classical And Quantum Algorithms For Finding Cycles, Jill Cirasella

Publications and Research

Quantum computing—so weird, so wonderful—inspires much speculation about the line between the possible and the impossible. (Of course, there is still unclarity about how “impossible” intractable problems are and about how “possible” quantum computers are.) This thesis takes a slightly different tack: instead of focusing on how to make the impossible possible, it focuses on how to make the possible easier.

More specifically, this paper discusses quantum algorithms for finding cycles in graphs, a problem for which polynomial-time classical algorithms already exist. It explains and compares the classical and quantum algorithms, and it introduces a few new algorithms and observations. …