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Theses/Dissertations

2009

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Voltage Stability Indices Based On Active Power Transfer Using Synchronized Phasor Measurements, Rui Sun Dec 2009

Voltage Stability Indices Based On Active Power Transfer Using Synchronized Phasor Measurements, Rui Sun

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In recent years and in the foreseeable future, power demands generally around the world and particularly in North America will experience rapid increases due to the increase of customers' requirements, while the development of transmission systems in North America is rather slow. Voltage stability assessment becomes one of the highest priorities to power utilities in North America. Voltage stability index is a feature for solving voltage stability problems. It is generated from the basic power flow equations and/or energy functions. The mathematical expression of a VSI is often written as a polynomial containing the systems real-time measurements such as voltage …

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Modeling The Cooling Phase Of The Lens Molding Process, Saravanan Kannan Dec 2009

Modeling The Cooling Phase Of The Lens Molding Process, Saravanan Kannan

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The lens molding process is a relatively new technique used to manufacture lenses, in particular, high precision aspheric lenses. In order to achieve the desired size and shape of the lens, the cooling process after pressing must be controlled precisely because of the time and temperature dependent viscoelastic behavior of glass near and below the molding temperature. This thesis gives a detailed description of a three-dimensional computational model for analyzing the cooling phase of the lens molding process. Conduction, convection and radiation are considered in the model by coupling a computational fluid dynamics analysis of the flow of nitrogen through …

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Molecular Analysis Of Split Hand/Foot Malformation (Shfm) At The Shfm3 And Shfm5 Loci, Megan Chryst-Ladd Dec 2009

Molecular Analysis Of Split Hand/Foot Malformation (Shfm) At The Shfm3 And Shfm5 Loci, Megan Chryst-Ladd

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Split hand/foot malformation (SHFM) is a congenital limb malformation observed in humans characterized by a reduction or loss of the central digits of the hands and/or feet. The condition affects one in every 8,500 to 25,000 births, accounting for 8-17% of all limb reduction defects. A tandem duplication of approximately 500 Kb has been determined to be the causative mutation at the SHFM3 locus. Patients that are heterozygous for this duplication have three copies of the genes BTRC, POLL, and DPCD as well as an extra copy of exons 6-9 of FBXW4. The SHFM3 critical region also contains the FGF8 …

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Interactive Perception For Cluttered Environments, Robert Willimon Dec 2009

Interactive Perception For Cluttered Environments, Robert Willimon

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Robotics research tends to focus upon either non-contact sensing or machine manipulation, but not both. This paper explores the benefits of combining the two by addressing the problem of extracting and classifying unknown objects within a cluttered environment, such as found in recycling and service robot applications. In the proposed approach, a pile of objects lies on a flat background, and the goal of the robot is to sift through the pile and classify each object so that it can be studied further. One object should be removed at a time with minimal disturbance to the other objects. We propose …

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Erk 1/2 And P38 Mapk Pathways Are Both Invovled In The Expression Of Interleukin-6, -8, And Cyclooxygenase-2 In Thrombocytes Stimulated With Lipopolysaccharide, Candace Hitchcock Dec 2009

Erk 1/2 And P38 Mapk Pathways Are Both Invovled In The Expression Of Interleukin-6, -8, And Cyclooxygenase-2 In Thrombocytes Stimulated With Lipopolysaccharide, Candace Hitchcock

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This study was conducted to determine if the p38 and ERK1/2 MAPK pathways are involved in transcription of IL-6, IL-8, and COX-2 in the chicken thrombocyte response to ligation of Toll-like receptor 4 (TLR4) by Salmonella minnesota lipopolysaccharide (LPS). Thrombocytes were isolated and subsequently treated with either p38 MAPK or ERK inhibitor, and then with LPS during in vitro cell culture. Transcription of IL-6, IL-8, and COX-2 mRNA was determined using real-time PCR. The experiments were repeated using pM, nM and μM concentrations of both inhibitors to test cell sensitivity. Stimulation with LPS induced expression of IL-6, IL-8 and COX-2 …

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A Voltage Flicker Suppression Device For Residential Air Conditioners And Heat Pumps, John Fox Dec 2009

A Voltage Flicker Suppression Device For Residential Air Conditioners And Heat Pumps, John Fox

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In some circumstances, voltage flicker due to the inrush current of residential heat pump can be a fairly visible to the residents as a slight flashing of the household's lights during the compressor starting event. The voltage flicker problem is caused by a variable contribution from sizable equivalent power system impedances and considerable inrush currents drawn by compressors. While this is not a new problem, and there are technologies on the market that attempt to alleviate the voltage flicker issue, no current solution attempts to correct for the problem at its root cause.
This thesis presents a device designed to …

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Identifying The Optimum Process Parameters Of Precision Glass Molding For Aspherical Lenses, Waqas Iqbal Dec 2009

Identifying The Optimum Process Parameters Of Precision Glass Molding For Aspherical Lenses, Waqas Iqbal

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The purpose of this research is to determine the optimum process parameters for the Precision Glass Molding (PGM) Process using Manufacturing Design, Design of Experiments and Metrology (for measuring the geometry of lenses). First, a custom machine is designed and manufactured which can carry out Precision Glass Lens Molding Experiments. This machine is then modified to improve temperature, position and force control. A literature review is performed to obtain data for process parameters that have been used in previous PGM studies. The collected data is then used in Design of Experiments to create twenty seven experiments that determine the optimum …

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Identifying And Comparing Key Process Attributes For Sustainable Building Delivery In India And The U.S., Prashanth Palanisamy Dec 2009

Identifying And Comparing Key Process Attributes For Sustainable Building Delivery In India And The U.S., Prashanth Palanisamy

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India is a rapidly developing nation with the associated brisk pace of construction. More sustainable building practices for construction in India would have social, environmental, and economic benefits. However, the key process attributes for successfully planning, designing, and constructing sustainable buildings in India are largely undefined. Other projects in India would benefit from a rigorous identification of these key process attributes which could help leapfrogging the sustainable building delivery in India to the best available practices.
Sustainable buildings require different delivery processes than traditional buildings; this can lead to process wastes due to unfamiliarity or incompatibility of the processes. These …

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Margaret Fuller's Lost Legacy: Literary Criticism, Donna Needham Dec 2009

Margaret Fuller's Lost Legacy: Literary Criticism, Donna Needham

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Margaret Fuller (1810-1850) is best known as a Transcendentalist, a friend of Ralph Waldo Emerson, and first editor of the Transcendentalist publication, The Dial. She is considered a feminist by those familiar with her early work, Woman in the Nineteenth Century. Fuller was also a literary critic and author of 'A Short Essay on Critics' the seminal American work on literary criticism. Her theory of criticism, like the criticism of Matthew Arnold twenty years later, was based on the philosophy of Goethe.
After stepping down as editor in 1842, Fuller continued to contribute criticisms and essays to The Dial until …

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Evaluation Of An Online Intelligent Transportation System (Its) Asset Management System, Tahera Anjuman Dec 2009

Evaluation Of An Online Intelligent Transportation System (Its) Asset Management System, Tahera Anjuman

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Intelligent Transportation System (ITS) enhances the performance of modern transportation systems by improving the reliability of travel times and reducing the risk of collisions and injuries. Recently, many public agencies have expressed a need for an ITS asset management system that will effectively and efficiently meet their requirements of managing associated resources, which often includes technologically sophisticated devices, computer hardware and software, and communications infrastructure. To address this need, the author evaluated different asset management systems for their potential efficacy to support public agencies requirements for an ITS asset management system. These requirements were identified through a nationwide survey of …

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'Light, More Light': The 'Light' Newspaper, Spiritualism, And British Society, 1881 - 1920., Brian Glenney Dec 2009

'Light, More Light': The 'Light' Newspaper, Spiritualism, And British Society, 1881 - 1920., Brian Glenney

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This thesis looks at the spiritualist weekly Light through Late Victorian, Edwardian, and World War I Britain. Light has never received any extended coverage or historical treatment yet it was one of the major spiritualist newspapers during this part of British history. This thesis diagrams the lives of Light's first four major editors from 1881 till the end of World War I and their views on the growth of science, God, Christ, evolution, and morality. By focusing on one major spiritualist newspaper from 1881 till 1920, this thesis attempts to bridge the gap in spiritualist historiography that marks World War …

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Vibrations Of Thin Plate With Piezoelectric Actuator: Theory And Experiments, Parikshit Mehta Dec 2009

Vibrations Of Thin Plate With Piezoelectric Actuator: Theory And Experiments, Parikshit Mehta

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Vibrations of flexible structures have been an important engineering study owing to its both deprecating and complimentary traits. These flexible structures are generally modeled as strings, bars, shafts and beams (one dimensional), membranes and plate (two dimensional) or shell (three dimensional). Structures in many engineering applications, such as building floors, aircraft wings, automobile hoods or pressure vessel end-caps, can be modeled as plates. Undesirable vibrations of any of these engineering structures can lead to catastrophic results. It is important to know the fundamental frequencies of these structures in response to simple or complex excitations or boundary conditions.
After their discovery …

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Charging Kinetics Of Electric Double Layer Capacitors, Clint Cagle Dec 2009

Charging Kinetics Of Electric Double Layer Capacitors, Clint Cagle

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A recent increase in the popularity of EDLCs and AC-EOF has necessitated a deeper understanding of the structure and charging kinetics of electrical double layers (EDLs) at electrode-electrolyte interfaces. Here, the charging kinetics of EDLs in nanoscale EDLCs is studied by a circuit model, a Poisson-Nernst-Planck (PNP) mo del, and molecular dynamics (MD) simulations. The results of the MD simulations demonstrate a linear charging behavior of EDLs near planar electrodes for both aqueous and organic electrolytes at charging below 90% and time larger than tens of picoseconds. Additionally, we will show that the circuit and PNP models are capable of …

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Structures Serving The Visibly Homeless: An Emergency Shelter Response In Charleston, South Carolina, Ellen Martin Dec 2009

Structures Serving The Visibly Homeless: An Emergency Shelter Response In Charleston, South Carolina, Ellen Martin

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This thesis is an architectural exploration into how to partially address the housing crisis affecting the visibly homeless population of Charleston, South Carolina. Thousands of men, women, and children in the United States are homeless in Charleston there is a significant and increasing number of visibly homeless. Those who sleep outside shelters are generally known as the 'visibly homeless' or street homeless. The visibly homeless is the most underserved group within the entire homeless population and is composed of those who sleep in places not intended for human habitation, such as bus stations, subway trains, automobiles, doorways, and abandoned buildings. …

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The Development Of A Mechatronics And Material Handling Course: Laboratory Experiments And Projects, James Shirley Dec 2009

The Development Of A Mechatronics And Material Handling Course: Laboratory Experiments And Projects, James Shirley

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Mechatronic systems integrate technologies from a variety of engineering disciplines to create solutions to challenging industrial problems. The material handling industry utilizes mechatronics to move, track, and manipulate items in factories and distribution centers. Material handling systems, because of their use of programmable logic controllers (PLC), PLC networks, industrial robotics, and other mechatronic elements, are a natural choice for a college instructional environment. This thesis offers insight and guidance for mechatronic activities introduced in a laboratory setting. A series of eight laboratory experiments have been created to introduce PLCs, robotics, electric circuits, and data acquisition fundamentals. In-depth case studies synthesize …

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An Examination Of The Night Hiking Experience In Parks And Protected Areas, John Beeco Dec 2009

An Examination Of The Night Hiking Experience In Parks And Protected Areas, John Beeco

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Many protected areas offer night programs for visitors; however, night hours have not been fully recognized as a potential resource in these areas. Night hours in protected areas could provide visitors with experiences unique to these times of the day. Also, typically low levels of visitation during night hours could provide visitors with additional or better suited opportunities to fulfill motivations and benefits sought during daytime activities. Furthermore, night hours could be used by managers to increase or temporally disperse use. The National Park Service's Natural Sounds and Natural Lightscapes programs provide a direction for the protection of this resource; …

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The Design Of An Ic Half Precision Floating Point Arithmetic Logic Unit, Balaji Kannan Dec 2009

The Design Of An Ic Half Precision Floating Point Arithmetic Logic Unit, Balaji Kannan

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A 16 bit floating point (FP) Arithmetic Logic Unit (ALU) was designed and implemented in 0.35µm CMOS technology. Typical uses of the 16 bit FP ALU include graphics processors and embedded multimedia applications.
The ALU of the modern microprocessors use a fused multiply add (FMA) design technique. An advantage of the FMA is to remove the need for a comparator which is required for a normal FP adder. The FMA consists of a multiplier, shifters, adders and rounding circuit. A fast multiplier based on the Wallace tree configuration was designed. The number of partial products was greatly reduced by the …

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Position Value And Wage Determinants In The Nhl, Sean Watterson Dec 2009

Position Value And Wage Determinants In The Nhl, Sean Watterson

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The landscape of the NHL has changed significantly following the lockout season that began in 2004. This paper studies the effects of the rule changes that followed the lockout, the rule changes effect on the documented discrimination against French Canadian players, and models the determinants of wage in the NHL for the three positions in the NHL: forward, defenseman, and goaltender.
The rule changes and stricter enforcement of existing rules resulted in an increase in average scoring by all teams. The rule changes caused the value of scoring to decrease, and they increased the value of skilled defensemen, particularly those …

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Digital Social Imagery In Silhouette, Ashley Triplett Dec 2009

Digital Social Imagery In Silhouette, Ashley Triplett

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Society places an extreme emphasis on outward appearance and beauty that is often unattainable. The short film, Silhouette, reminds audiences of the dangers that can result from society's infatuation with physical perfection, and the film's production is the focus of this thesis. The goal of the film is to effectively communicate the impact of society on an individual's self-worth and self-image and to illustrate the consequences that result when trying to attain physical perfection. An integral part of this project is an examination of how women have been portrayed in art historically as compared to present day. To visualize …

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An Animation Framework For Improving The Comprehension Of Tinyos Programs, Sravanthi Dandamudi Dec 2009

An Animation Framework For Improving The Comprehension Of Tinyos Programs, Sravanthi Dandamudi

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To meet the increasing demand for monitoring of the physical world, there has been an increase in the development of wireless sensor network applications. The TinyOS platform has emerged as a de facto standard for developing these applications. The platform offers a number of advantages, with its support for concurrency, power-efficient operation, and resource-constrained hardware chief among them. However, the benefits come at a price. Even without the TinyOS platform, the inherent parallel and distributed nature of these applications makes it difficult for developers to reason about program behavior. Further, the TinyOS programming model adopts
asynchronous, split-phase execution semantics. Developers …

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Low-Dose Of Sodium Arsenite Causes Delayed Differentiation In C2c12 Mouse Myoblast Cells Through The Repression Of The Transcription Factor Myogenin, Amanda Steffens Dec 2009

Low-Dose Of Sodium Arsenite Causes Delayed Differentiation In C2c12 Mouse Myoblast Cells Through The Repression Of The Transcription Factor Myogenin, Amanda Steffens

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A number of epidemiological studies have correlated arsenic exposurwith cancer, skin diseases, cardiovascular diseases, and adverse developmental outcomes such as stillbirths, spontaneous abortions, neonatal mortality, low birth weight, and delays in the use of musculature. The current study used C2C12 mouse myoblast cells to examine whether low concentrations of arsenic could alter their differentiation into myotubes, which would indicate that arsenic has the ability to act as a developmental toxicant. Myoblast cells were exposed to 20nM sodium arsenite and allowed to differentiate into myotubes and expression of the muscle-specific transcription factor myogenin, along with the expression of myosin light chain …

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Relationships Between Lane Change Performance And Open-Loop Handling Metrics, Robert Powell Dec 2009

Relationships Between Lane Change Performance And Open-Loop Handling Metrics, Robert Powell

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This work deals with the question of relating open-loop handling metrics to driver-in-the-loop performance (closed-loop). The goal is to allow manufacturers to reduce cost and time associated with vehicle handling development. A vehicle model was built in the CarSim environment using kinematics and compliance, geometrical, and flat track tire data. This model was then compared and validated to testing done at Michelin's Laurens Proving Grounds using open-loop handling metrics. The open-loop tests conducted for model validation were an understeer test and swept sine or random steer test. Four commonly used handling metrics (steady state yaw rate gain, yaw rate damping …

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Friction Stir Welding Process And Material Microstructure Evolution Modeling In 2000 And 5000 Series Of Aluminum Alloys, Harshavardhan Yalavarthy Dec 2009

Friction Stir Welding Process And Material Microstructure Evolution Modeling In 2000 And 5000 Series Of Aluminum Alloys, Harshavardhan Yalavarthy

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Interactions between the rotating and advancing pin-shaped tool (terminated at one end with a circular-cylindrical shoulder) with the clamped welding-plates and the associated material and heat transport during a Friction Stir Welding (FSW) process are studied computationally using a fully-coupled thermo-mechanical finite-element analysis. To surmount potential numerical problems associated with extensive mesh distortions/entanglement, an Arbitrary Lagrangian Eulerian (ALE) formulation was used which enabled adaptive re-meshing (to ensure the continuing presence of a high-quality mesh) while allowing full tracking of the material free surfaces. To demonstrate the utility of the present computational approach, the analysis is applied to the cases of …

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Effect Of Oscillating And Static Retort Thermal Processing Technology Using An Institutional Size Pouch, Judith Trevino Dec 2009

Effect Of Oscillating And Static Retort Thermal Processing Technology Using An Institutional Size Pouch, Judith Trevino

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The effects of oscillating and static retort thermal processing on heat penetration using an institutional size pouch were evaluated. A literature review of general information on retort thermal processing, process modes, processing mediums, retort pouches and starch was presented.
Frigex-W starch (National Starch Food Innovation) and water mixtures were prepared at three different concentrations (1%, 3% and 5%). Five replications of starch and water mixtures were processed using water spray as the processing medium in institutional size retort pouches (29.2 cm. x 38.1 cm.) using both oscillating and static processing modes.
Viscosity (by Brookfield viscometer and Bostwick consistometer), residual air …

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Using A Multimedia Assessment Tool To Impact Evolution Education Strategies In South Carolina's Public High Schools, Matthew Johnson Dec 2009

Using A Multimedia Assessment Tool To Impact Evolution Education Strategies In South Carolina's Public High Schools, Matthew Johnson

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The theory of evolution is widely accepted as one of the fundamental disciplines of modern science. Evolution provides a foundation for all aspects of biology, and thus it is essential that present and future biologists have a detailed understanding of evolutionary principles. However, since the famous Scopes trial in 1925, the teaching of evolutionary theory in the public school system has been under attack. Though several court cases over the last 85 years have continually supported evolution and discredited creationism (the idea that evolution cannot explain the diversity of life on earth and therefore must have arisen through the influence …

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A Study Of The Mesosphere-Lower Thermosphere: Noctilucent Cloud Observations And Rocket Borne Density Measurements, Shelton Simmons Dec 2009

A Study Of The Mesosphere-Lower Thermosphere: Noctilucent Cloud Observations And Rocket Borne Density Measurements, Shelton Simmons

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Herein, a study of a noctilucent cloud, NLC, display from 17 July 2007 is analyzed. A photogrammetric analysis was applied to time lapsed photographs taken from two observation sites, RŸgen and KŸhlungsborn, Germany. Both Kelvin-Helmholtz instabilities and internal gravity waves were identified during the NLC display based on the typical characteristics of such waves in the mesopause region. With the two observation sites, the location of details can be identified with an accuracy of ±0.125¡ longitude and ±0.5¡ latitude. A gravity wave with a wavelength of 50km and Kelvin-Helmholtz instability or gravity wave of wavelength 16.5km were observed. The 16.5km …

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Principal Component Thermography For Steady Thermal Perturbation Scenarios, Rohit Parvataneni Dec 2009

Principal Component Thermography For Steady Thermal Perturbation Scenarios, Rohit Parvataneni

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The work focuses on the qualitative enhancement of Thermographic Inspection data using Principal Component Analysis technique. A new processing tool named Economical Singular Value Decomposition (SVD) is proposed for analyzing the infrared image sequences acquired from the test specimen.
Experiments are carried out on test sample using thermal excitation modalities such as flash, halogen and induction to create temperature variations. The infrared (IR) image sequence containing the information about the sample is captured using IR cameras. The acquired IR image sequences are processed using the proposed Economical SVD which projects the matrix of raw pixel values of image sequence into …

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Measuring Freedom: An Analysis Of The Economic Freedom Index, Derek Mcafee Dec 2009

Measuring Freedom: An Analysis Of The Economic Freedom Index, Derek Mcafee

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The creation and empirical use of economic freedom indices has produced a growing amount of literature over the last decade. A survey of this literature is provided, and the difficulty of measuring this concept, as well as the usefulness and limits of the various indices are discussed. The indices are reduced to their components, and testable models are used in order to determine which components are most important. Secure property rights are found to be the most important component driving the results. The results are consistent with previous studies, which indicate that greater economic freedom is related to greater growth …

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Neomycin Enhances Glutaraldehyde Crosslinking And Glycosaminoglycan Stability In Bioprosthetic Heart Valves, Vincent Friebe Dec 2009

Neomycin Enhances Glutaraldehyde Crosslinking And Glycosaminoglycan Stability In Bioprosthetic Heart Valves, Vincent Friebe

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The native heart valve will open and close an astonishing 3 billion times in the average lifetime, implicating immense biomechanical ramifications that necessitate near-flawless structure and functional behavior. Deviations from this idyllic function as a result of heart valve disease (HVD) affect millions of individuals worldwide and result in over 275,000 heart valve replacements worldwide every year. Glutaraldehyde (GLUT) cross-linked porcine aortic heart valves, a common type of bioprosthetic heart valve (BHV), are used frequently in these valve replacement surgeries. The native valve leaflets entail a tri-composite design of type I collagen, elastin and glycosaminoglycans (GAGs), each of which are …

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The Effect Of Moderate Exercise On Folliculogenesis, Cortisol, Estradiol And Luteinizing Hormone In Mares, Dale Kelley Dec 2009

The Effect Of Moderate Exercise On Folliculogenesis, Cortisol, Estradiol And Luteinizing Hormone In Mares, Dale Kelley

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Assisted reproductive technologies allow mares to remain in training and produce offspring; however, limited data regarding the impact of exercise on folliculogenesis exists. Mares in training are reported to have reduced embryo recovery rates and ovulated smaller follicles. The objectives of this study are to evaluate the effect of exercise on folliculogenesis using ultrasound technology. Additionally, cortisol, luteinizing hormone (LH), follicle stimulating hormone (FSH) and estradiol concentrations in mares were evaluated. The exercise period was from April to September 2008 at Latitude: 34¡ 41' 1' N. Thirteen horses were assigned to Exercise (n=6) or Control group (n=7). Mares were exercised …

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