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Visual Contributions To Spatial Perception During A Remote Navigation Task, Candace Lee Eshelman-Haynes

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The purpose of this study was to explore the implications of perception and action coupling for the design of control and display interfaces in remotely piloted vehicles. Three experiments were conducted: spatial arrangement, path perception, and remote navigation. The results showed that panning independent of forward motion gives observers a greater sense of depth in a scene and aides in efficient navigation while rotation during forward motion results in ambiguities during passive observation. This research has implications for the design of control and visualization interfaces for remote navigation.

Ischemic Stroke In Type Ii Diabetic Mice: Deregulation Of Sdf-1a/Cxcr4 Axis, Avik Das

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Type 2 diabetes mellitus is a major risk factor for ischemic stroke. Also diabetes is associated with poor outcome after stroke. Underlying mechanisms are however not fully understood. Alteration in the expression of the SDF-1a/CXCR4 axis, which is important for ischemic tissue repair, can be a probable cause. In this study, we have determined the expression of SDF-1a/CXCR4 in the brains of type II diabetic mice at basal and in response to ischemic stroke and have investigated a method for overexpression of SDF-1a in the brains of the diabetic mice. Adult male C57BLKS/J mice (db/db) of age 8 weeks were …

High Voltage Dc Converter Systems Modeling, Simulation And Analysis, Manish A. Dalal

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The thesis provides insights into important modeling techniques to model the converter system, machine design, control and power stages and integration of the various sub systems to simulate the system level performance. This innovative modeling and simulation project is very relevant to optimizing the system performance, designing the sub circuits, components selection, predicting the system stability and impulse responses. The thesis presents modeling and simulation of three different 270VDC converter systems and comparing their performances against each other. The 270VDC converter system accepts either Generator 3-phase AC voltages or fixed three voltage source followed by single or dual converter stages …

Fuzzy Logic Control Of A Switched-Inductor Pwm Dc-Dc Buck Converter In Ccm, Terry Kolakowski

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Modern electronics are operating at lower voltages with higher currents, requiring power converters to deliver these requirements efficiently. In this thesis, a switch-inductor buck converter is designed for the required specifications; and for the selected design, component losses and efficiency are calculated. A MATLAB/Simulink model is constructed, and tested in the presence of load and source disturbances to show the converter cannot maintain the desired output voltage when the disturbances are applied.

A fuzzy logic PID controller is designed to regulate the duty cycle of the converter to control the output voltage. Control surfaces are designed for proportional, integral, and …

Bench-Scale Conversion Of Carbon Dioxide To A Hydrocarbon Fuel, Melissa L. Kennedy

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There is a growing concern about the effects of global warming that many believe is anthropogenically caused. As such, scientists are trying to uncover a viable alternative fuel source and establish a way to reduce atmospheric carbon dioxide levels. A potential solution that addresses both of these aspects would be to capture atmospheric carbon dioxide and convert it into a natural gas, in particular methane, which could be used as an energy source. A laboratory-scale experiment using 6 160 mL microcosms (3 with anaerobic wetland soil and 3 relatively soil free) and 2 7.2 L bioreactors was conducted to learn …

Error Management Training: Further Tests Of Mediation And Moderation, Zachary T. Kalinoski

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This study investigated an alternative training approach that would improve transfer performance scores above traditional training approaches. Specifically, error-management training was proposed to help trainees learn complex tasks, as opposed to error-avoidant training approaches, which sought to give trainees step-by-step protocols for learning that would minimize the occurrence of errors during training. This study was designed to examine the effects of training type on transfer performance and transfer errors, as well as the effects of meta-cognition, emotion control and cognitive appraisals as mediators of the training type-performance relationship. A third issue of this study investigated the personality-training type interactions from …

Conductance Modulation In Bilayer Graphene Nanoribbons, Kirti Kant Paulla

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Graphene nanoribbons are among the recently discovered carbon nanostructures, with unique characteristics for novel applications. One of the most important features of graphene nanoribbons, from both basic science and application points of view, is their electrical conductivity. In this research, we study the electrical conductance of single and double layer nanoribbons of specified widths and edge geometries. The calculations are carried out using ab initio quantum mechanical simulations for obtaining the optimized atomic configurations of the nanoribbons and their electronic structures. These results are then used to calculate the conductance characteristics via Green's function approach to the Landauer's formalism. We …

Impact Of Diabetes On Ace/Ace2 Balance And Angiotensin Ii Type 1 Receptor Expression In Db/Db Diabetic Mice, Malav Navinchandra Madhu

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Alterations in the renin-angiotensin system (RAS) are considered to be crucial for the development of diabetic complications like hypertension and nephropathy. Our previous work demonstrated role of AT1 receptors (AT1R) in the development of hypertension in db/db diabetic mice. The aim of this study was to test the hypothesis that there is upregulation of renal AT1R and imbalance in renal ACE/ACE2 homeostasis in db/db mice. In addition, we hypothesize that treatment with an anti-hyperglycemic or an AT1R blocker will correct this imbalance. Five week old control and db/db mice were housed in metabolic cages for 24 hour collection of urine. …

New Formic Acid Fuel Cell Orientations To Reduce The Cost Of Cell Components, John Calvin Holtkamp

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Formic acid fuel cells show the potential of outperforming or replacing direct methanol fuel cells. A number of issues need to be overcome in order for fuel cells, specifically formic acid fuel cells, to be seriously considered for use in small electronic devices. One of the largest issues inhibiting the commercial success of fuel cells is the cost of the components. The catalyst and ion-conducting membrane, key components in a fuel cell, are both expensive. With the current amount of costly materials needed to construct a fuel cell, fuel cells will have limited success in becoming mainstream power sources in …

A Morphometric Analysis Of The Highly Variable Clypeasteroid, Periarchus Lyelli, Lauren Elizabeth Williamson

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The Late Eocene echinoid, Periarchus lyelli (Conrad, 1834), known for its wide geographic range, high abundance, and specific stratigraphic range, is an ideal example of a guide fossil. However, due to its highly variable test morphology, many have questioned if, in fact, this sand dollar is actually two or three distinct species that have been misclassified. A preliminary study on this subject has been performed on specimens from Mississippi, North Carolina and South Carolina (Williamson, 2006), showing significant separation in test shapes. Continuing previous research, this study analyzes the test shapes of P. lyelli over its entire North American geographic …

Human Cognitive Biases And Heuristics In Image Analysis, Mary E. Fendley

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Humans often employ cognitive heuristic principles when making decisions. These cognitive heuristic principles allow the human to simplify the decision making task, and can, by their very nature, lead to deviations, referred to as cognitive biases, which influence the quality of the decisions.

While the role of heuristics and biases have been studied in judgmental decision making tasks, very little research on cognitive heuristics and biases has been done on decision making in complex, dynamic tasks. The research undertaken and discussed herein investigates the existence and impact of cognitive biases in time-critical decision making. To do so, this research uses …

Comparison Of The Electrochemical Properties Of Ethanol In Perchloric Acid And Ionic Liquids, Sandra Felix-Balderrama

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1-Ethyl-3-Methylimidazolium Tetrafluroborate (EMImBF₄) and 1-Ethyl-3-Methylimidazlium Bis(trifluoromethanesulfonyl)imide (EMImTFSI) ionic liquids were synthesized and characterized in order to study the electrochemical oxidation of ethanol in these ionic liquids on a platinum surface electrode.

It was found that pure EMImBF₄ exhibits an electrochemical window of 4.4 V,while EMImTFSI exhibits an electrochemical window of 5.0 V.

Electrochemical study of ethanol in perchloric acid showed that the oxidation of ethanol strongly depends on the concentration of ethanol and on the temperature of the solution. The poisoning of the platinum electrode only depends on the concentration of ethanol. At a low concentration of …

Cationic Exchange Reactions Involving Dilithium Phthalocyanine, Morgan M. Hart

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Dilithium phthalocyanine (Li₂Pc) consists of an aromatic macrocycle possessing a doubly negative charge and two Li⁺ counterions. One Li⁺ ion is easily displaceable while the other remains coordinated to the phthalocyanine ring. The displaceable Li⁺ cation can be exchanged with other cations, such as a singly charged tetra-alkyl ammonium cation, by using several variations of a general procedure. It has been demonstrated that tetraalkylammonium lithium phthalocyanines (TAA-LiPcs) can be successfully and reproducibly synthesized with yields ranging from 54.5% up to 64.3%. All TAA-LiPcs demonstrated poor solubilities from approximately <0.2 mg/mL to 5 mg/ml in the solvents tested (with the exception of tetrapropylammonium lithium phthalocyanine and tetrahexylammonium lithium phthalocyanine). All of the TAA-LiPcs synthesized were dark-purple in color, with the exception of tetraheptylammonium lithium phthalocyanine and tetraoctylammonium lithium phthalocyanine. These two compounds were dark - blue in color. Melting points varied greatly from >370.4°C to 157.9°C and depended greatly upon …

A Spectroscopic Investigation Of A Surface-Discharge-Mode, Dielectric Barrier Discharge, Scott Alan Stanfield Ii

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The use of aerodynamic actuators, such as leading edge slats, trailing edge flaps, roughing strips and ailerons interact with the air during flight, providing maneuverability for air vehicles. These mechanical devices have many inherent, detrimental attributes, such as space requirements on the wing, added wing weight, second response times, increased drag, and increased airframe vibration, resulting in the production of noise. The potential to eliminate or improve upon these detrimental attributes may be realizable by replacing the current mechanical actuators with plasma actuators. Specifically, the surface-discharge-mode, dielectric barrier discharge (SDBD), plasma actuator has a response time on the order of …

Fifty Years Of The European Court Of Human Rights Viewed By Its Fellow International Courts, Paolo G. Carozza

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Remarks by Paolo Carozza, President of the Inter-American Commission on Human Rights Strasbourg, January 30, 2009

Type I Error Rates And Power Estimates For Several Item Response Theory Fit Indices, Bradley R. Schlessman

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Despite frequent use of the adjusted chi-square to degrees of freedom ratio (χ2/df) test for Item Response Theory fit (Drasgow, Levine, Tsien, Williams. and Mead, 1995), there remains a lack of empirical testing of the statistic's Type I error rates and power. The present study compared the adjusted χ2/df test to two other commonly used IRT fit statistics. The other fit indices examined were S-χ2 (Orlando and Thissen, 2000) and χ2* (Stone's, 2000). This study also addressed misfit based on the possibility that the item responses analyzed were created based on a different response process than that assumed by the …

A Software Framework For The Design, Testing And Deployment Of Control Systems For Autonomous Robotics, Duane Stanley Bolick Jr.

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Simulation and control of robotic agents are common enough tasks among computer science and engineering researchers that there exists a large variety of software applications, toolkits, and programming frameworks designed to facilitate such research. The intent of this project is to provide an autonomous robotics simulation and control framework with sufficiently useful tools and reference implementations so as to be immediately useful to basic users, as well as easily understood and extended by software developers and robotics researchers.

As such, this document describes the implementation of a general networking toolkit, an autonomous robotics extension framework, and an autonomous robotics simulator …

Using Two Channel Communication To Study Selective Auditory Attention Using Air And Bone Conducted Interfaces, Kutbi Nuruddin Kaliyakuwawala

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The purpose of this study was to evaluate the human capability to use selective auditory attention across the two different hearing pathways, air conduction and bone conduction. Four two channel communication systems were used as a basis for comparison: (1) both channels presented via headphones (left ear and right ear each represent a different channel), (2) two channels presented via loudspeakers placed at 135° and 225°, (3) one channel presented via headphones (both ears) and one channel to bone vibrator (placed at the condoyle), and (4) one channel presented via bone vibrator and one channel via loud speakers (placed at …

Measuring Applicant Faking With Job Desirability: Prevalence, Selection, And Measurement Issues In An Applied Sample, Esteban Tristan

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Research has found that the use of social desirability scales to measure faking is problematic. The current study employed a job desirability scale consisting of job-specific bogus biographical items as an alternative faking measure in an applied setting. Using a 2 (applicants versus incumbents) x 2 (sales versus managers) design, participants (N = 958), participants completed a set of personality, social desirability, and job desirability measures. Results indicated that applicants outscored incumbents on personality measures. However, the effect size for conscientiousness was larger for the manager job whereas the effect size for extraversion was larger for the sales job, indicating …

The Effects Of Depth And Eccentricity On Visual Search In A Depth Display, George Angelo Reis

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The attribute of depth has been shown to provide saliency or conspicuity for items in a visual search task. Novel displays that present information in real physical depth offer potential benefits. Previous research has studied depth in visual search but depth was mostly realized without real physical separation of display elements. This study aimed to better understand the effects of real physical depth and eccentricity on visual search in a depth display. Through this understanding, we can appropriately utilize this new technology. An experiment was conducted to test four hypotheses regarding how depth, eccentricity, target feature, and screen location would …

Graphical User Interface (Gui) To Study Different Reconstruction Algorithms In Computed Tomography, Shital K. Abhange

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Computed tomography (CT) imaging relies on computational algorithms to reconstruct images from projections gathered from the CT scan. Depending on the scanner geometry, different types of reconstruction algorithms can be used. To study these different types of reconstruction algorithms in a user-friendly way, a software tool was built. The aim of the thesis was to provide a software platform to access a number of previously implemented reconstruction algorithms with ease and minimal knowledge of the reconstruction code. The goal was accomplished by building a Graphical User Interface (GUI) using MATLAB 7.7.0 (R2008b). In addition to creating mathematical objects and invoking …

Characterization Of Infectivity And Pathogenesis Of Partially Reconstructed 1918 And Highly Pathogenic Avian Influenza Viruses In The Balb/C Mouse Model, John Allen Pyles

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Influenza viruses are consistently responsible for an average of 20,000 deaths and 114,000 hospitalizations per year. To a great extent, these viruses always stay one step ahead of the available vaccines and people's immunity year after year because they have the ability to either mutate part of their genetic material, or to be transmitted from one species to another. That same genetic variability explains why highly pathogenic influenza viruses emerge that cause great mortality over several countries resulting in pandemics. Highly pathogenic strains of influenza A virus have emerged occasionally in recent history, producing pandemics such as the one in …

A Self-Configuring 3-D Body Scanner, David James Holtkamp

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A flexible, self-configuring body scanner is described that is capable of capturing and merging range data from multiple views into a single coordinate system without the use of registration. The scanner uses two disconnected frames with embedded lights to merge the coordinate systems of multiple cameras. The frame also serves in finding the laser plane as the lasers are swept over the surface from multiple locations. Both hardware and software details are presented as well as techniques for automating most aspects of the scanner. A new implicit surface implementation is also described for processing and triangulating the resulting point clouds …

Localization And Surveillance Using Wireless Sensor Network And Pan/Tilt Camera, Pratikkumar U. Desai

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The ever growing challenges in hostile environments, health care and warzone require accurate indoor localization and surveillance. The de facto localization technique using GPS has poor indoor performance due to the complexity of the indoor environment. Other Radio frequency based indoor localization techniques are unable of accurate localization due to multipath fading.

In this thesis, a system consisting of Cricket wireless sensor motes, a camera and a Pan/Tilt gimbal is proposed to solve the indoor localization and surveillance problems. The system is easy to deploy, is cost effective and gives accurate results. The Crickets motes use the Time Difference of …

Conservation Genetics Of A Near Threatened Freshwater Mussel Species (Lampsilis Cardium) And Improved Prospects For Recovery: How Nuclear And Mitochondrial Dna Analyses Inform Natural History And Conservation, Chad D. Ferguson

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Freshwater mussels (Bivalvia: Unionidae) are among the most imperiled organisms in North America. While there is an urgent need for effective conservation planning and management of these organisms, important basic biological information is lacking. This research characterizes levels of genetic diversity and population structure in the Near Threatened (IUCN) freshwater mussel Lampsilis cardium in populations from Twin Creek (southwest Ohio), Little Darby and Big Darby Creeks (central Ohio), and Little Muskingum River (eastern Ohio) and assesses the extent to which regional geological events explain population structuring. Data from the congener Lampsilis ovata from Clinch River (Tennessee) are included for comparison. …

Attentional Limitations And The Visual Pathways, Satomi Maeda

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The present study tested the hypothesis that three visual pathways (i.e. parvocellular, magnocellular, and koniocellular pathways) may influence the degree of dual-task interference using dual-task methodology. The magnocellular pathway consists of feature-coding mechanisms that are sensitive to transients and motion, and is thought to process information about the locations and movements of objects. The parvocellular pathway consists of feature-coding mechanisms that are sensitive to red-green and brightness information, while the koniocellular pathway consists of feature-coding mechanisms that are sensitive to blue-yellow chromatic information. Both the parvocellular and the koniocellular pathway are thought to process information useful for identifying objects. The …

Using Morphometrics, Phylogenetic Systematics And Parsimony Analysis To Gain Insight Into The Evolutionary Affinities Of The Calymenidae Trilobita, Alex J. Chestnut

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The most common trilobite in the Silurian carbonates of Ohio - especially the Springfield Dolomite - is a species that has been assigned to at least five genera over the past 100 years. This trilobite has been variously referred to as Calymene celebra, Apocalymene celebra, Flexicalymene celebra, Gravicalymene celebra, and Sthenarocalymene celebra. Reexamination of the species "Calymene" celebra through parsimony and morphometric analysis was conducted to properly place this calymenid species within the correct genus. What compounds the confusion is that the characters used to seperate the genera within the family Calymenidae, and therefore create the basis for the argument …

Application Of Modern Principles To Demand Forecasting For Electronics, Domestic Appliances And Accessories, Gregory Daniel Noble

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Royal Philips is a large scale producer of consumer electronics, personal appliances, lighting, and healthcare appliances. Demand data from 12 Business Units (BU) of Royal Philips was examined in the study; four business units from each of three divisions: DAP, PA, and CE. From the data supplied, different forecast techniques were evaluated to determine which procedure produces the highest quality forecasts. Three forecasting techniques were evaluated using the provided data. The three forecasting techniques evaluated are the exponential smoothing forecasting method, the exponential smoothing with a linear trend forecasting method, and the Winters forecasting method.

The Visual Basic for Applications …

Reorganization Of Ia Afferent Synapses On Motoneurons After Peripheral Nerve Injuries, Haley E. Titus

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After peripheral nerve injuries patients lose and do not recover the stretch reflex which leads to altered locomotor function. The focus of this thesis is to investigate the structural integrity of the central connection between Ia afferents and alpha motoneurons that mediate the stretch reflex. The overall hypothesis is that the density and distribution of Ia synapses on motoneurons is altered after peripheral nerve injuries. Analysis of Ia afferent-motoneuron contacts, revealed by vesicular glutamate transporter 1 (VGLUT1) immunoreactivity, on the soma and dendritic arbor of motoneurons after peripheral nerve injuries revealed major reorganizations in the distribution and density of Ia …

Identification Of Potential Protein Biomarkers Of Low Level Kidney Degradation, Christopher Lee Woolard

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The purpose of this research was the identification of potential dose-dependent and time-dependent serum protein biomarkers of low level kidney degradation in a rat model. Potential biomarkers were evaluated based on differential protein expression between control and dosed samples in rat serum. Proteins of interest demonstrated upregulation at a minimum 1.5 fold increase in protein concentration control versus dosed sample. In order to identify common biomarkers of kidney decrement, three nephrotoxins were chosen to target specific locations of the kidney: 1) D-Serine, which causes necrosis of the proximal straight tubules, 2) Puromycin, an antibiotic that degrades the Glomerular Basement Membrane …