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High-Resolution Stratigraphy At A Coastal Drillhole, Beth Wrege May 2007

High-Resolution Stratigraphy At A Coastal Drillhole, Beth Wrege

All Theses

Lithologic descriptions of continuous core interpreted in conjunction with borehole geophysical logs were used to determine thicknesses of hydrologic and geologic units at CR-622 in the coastal plain of North Carolina. Borehole geophysics was used to adjust the position of core loss within each cored interval and to supplement lithology to determine the stratigraphy of missing segments of core. Although some geophysical logs produce non-unique lithologic solutions, a complete normal stratigraphic profile may be obtained with the addition of continuous core. Curve characteristics within geophysical logs provide precise identification of transitional sequences and can be used to calibrate lithostratigraphy. The …

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Optimal Placement Of Metal Foils In Ultrasonic Consolidation Process, Raji Rexavier May 2007

Optimal Placement Of Metal Foils In Ultrasonic Consolidation Process, Raji Rexavier

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Ultrasonic Consolidation is a combination of additive and subtractive
manufacturing processes resulting in considerable material waste. This waste is a
function of the geometry of the part being manufactured and of the relative
placement of the layer with respect to the metal bands. Thus the waste may be
minimized by careful choice of the layer angle and offset from the original
position.
Previous work done in this field had developed an automated algorithm which
optimally places and orients the individual slices of the STL file of the artifact
being manufactured. However, the problem was solved on a 2-D scale and …

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Clemson Commencement Program, May 2007, Clemson University May 2007

Clemson Commencement Program, May 2007, Clemson University

Clemson Commencement Programs

No abstract provided.

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The Glow Discharge - A Multifaceted Optical Emission Source: From Solids Analysis To Metalloproteins, Timothy Brewer May 2007

The Glow Discharge - A Multifaceted Optical Emission Source: From Solids Analysis To Metalloproteins, Timothy Brewer

All Dissertations

Glow discharges (GD) are well known for their application to direct solids elemental analysis of metals and alloys by optical emission spectroscopy (GD-OES). The most successful application of GD-OES has been the analysis of solid materials since the GD provides rapid, direct bulk and depth profiling analysis of solids, metals, powders, polymers, glasses and ceramics. However, solids analysis has typically suffered from the lack of true analytical blanks and the inability to study particulate solids in their native state. An approach for the analysis of solid powdered material entrapped in a sol-gel matrix by radio frequency glow discharge optical emission …

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Analytical And Intelligent Techniques For Dynamically Secure Dispatches, Aftab Alam May 2007

Analytical And Intelligent Techniques For Dynamically Secure Dispatches, Aftab Alam

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The NERC August 14th Blackout report brought out by the task force cited 'failure to ensure operation within secure limits' as one of the main reasons. Many of the numerous recommendations focused on the need for better real-time tools for operators and reliability coordinators. In the absence of such tools the operators are limited to operating in conservative secure operating regions established using offline studies. At the same time, with the fast inception of deregulation, the need to ensure a reliable and secure power system has become all the more vital. The success of a competitive market is dependent upon …

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Domination And Decomposition In Multiobjective Programming, Alexander Engau May 2007

Domination And Decomposition In Multiobjective Programming, Alexander Engau

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During the last few decades, multiobjective programming has received much attention for both its numerous theoretical advances as well as its continued success in modeling and solving real-life decision problems in business and engineering. In extension of the traditionally adopted concept of Pareto optimality, this research investigates the more general notion of domination and establishes various theoretical results that lead to new optimization methods and support decision making.
After a preparatory discussion of some preliminaries and a review of the relevant literature, several new findings are presented that characterize the nondominated set of a general vector optimization problem for which …

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An Infrastructure To Support Interoperability In Reverse Engineering, Nicholas Kraft May 2007

An Infrastructure To Support Interoperability In Reverse Engineering, Nicholas Kraft

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An infrastructure that supports interoperability among reverse engineering tools and other software tools is described. The three major components of the infrastructure are: (1) a hierarchy of schemas for low- and middle-level program representation graphs, (2) g4re, a tool chain for reverse engineering C++ programs, and (3) a repository of reverse engineering artifacts, including the previous two components, a test suite, and tools, GXL instances, and XSLT transformations for graphs at each level of the hierarchy. The results of two case studies that investigated the space and time costs incurred by the infrastructure are provided. The results of two empirical …

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Associations Between Age At School Entry And Academic Performance: Using Data From A Nationally Representative, Longitudinal Sample, Dawn Fleischman May 2007

Associations Between Age At School Entry And Academic Performance: Using Data From A Nationally Representative, Longitudinal Sample, Dawn Fleischman

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The purpose of this study was to examine the associations between age at school entry and academic performance in kindergarten through the fifth grade. The study utilized the Early Childhood Longitudinal Study, Kindergarten Class of 1998-1999 (ECLS-K) dataset that includes a nationally representative sample that was collected over a six year period and compiled by the National Center for Educational Statistics (NCES).
Even when controlling for the variables of gender, race, socioeconomic status, and disability, the analyses revealed that the youngest students did not perform as well in reading and math as their school entry peers through the fifth grade. …

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Models Of Semi-Systematic Visual Search, Sourav Das May 2007

Models Of Semi-Systematic Visual Search, Sourav Das

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Visual search is an important aspect of many examination and monitoring tasks. As a result, visual search performance has been the topic of many empirical investigations. These investigations have reported that individual search performance depends on subject factors such as search behavior, which has motivated the development of models of visual search that incorporate this behavior. Search behavior ranges from random to strictly systematic; variation in behavior is commonly assumed to be caused by differences in memory retrieval and search strategy. Accordingly, a mathematical model of semi-systematic search is proposed here that can account for both memory retrieval and other …

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Adaptive Treatment Of Van Der Waals Interactions In Empirical Bond-Order Potentials With Application To Junction Formation In Carbon Nanotubes, Aibing Liu May 2007

Adaptive Treatment Of Van Der Waals Interactions In Empirical Bond-Order Potentials With Application To Junction Formation In Carbon Nanotubes, Aibing Liu

All Dissertations

Molecular dynamics (MD) simulation of reactive condensed-phase hydrocarbon systems is a challenging research area. The AIREBO potential is particularly useful in this area because it can simulate bond breaking and bond forming during chemical reactions. It also includes non-bonded interactions for systems with significant intermolecular interactions.

The first part of this dissertation describes a method to adaptively incorporate van der Waals interaction of carbon atoms into the AIREBO force field. In bond-order potentials, the covalent bonding interactions adapt to the local chemical environment, allowing bonded interactions to change in response to local chemical changes.
Non-bonded interactions should adjust to their …

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Random Vectors Over Finite Fields, Shannon Lockard May 2007

Random Vectors Over Finite Fields, Shannon Lockard

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The study of random objects is a useful one in many applications and areas of mathematics. The Probabilistic Method, introduced by Paul Erdos and his many collaborators, was first used to study the behavior of random graphs and later to study properties of random objects. It has developed as a powerful tool in combinatorics as well as finding applications in linear algebra, number theory, and many other areas. In this dissertation, we will consider random vectors, in particular, dependency among random vectors. We will randomly choose vectors according to a specified probability distribution. We wish to determine how many vectors …

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Hydrothermal Crystal Growth Of Oxides For Optical Applications, Colin Mcmillen May 2007

Hydrothermal Crystal Growth Of Oxides For Optical Applications, Colin Mcmillen

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There is great interest in obtaining coherent radiation in all regions of the optical spectrum. This dissertation explores the hydrothermal growth of crystals that function in two regions currently inaccessible by solid state devices. The first gap exists in the deep-UV region, particularly below 200 nm. Some materials such as LBO and BBO can generate coherent light at wavelengths as low as 205 nm. The growth of these materials was explored to investigate the feasibility of the hydrothermal method as a new technique for growing these crystals. Particular attention was paid to the descriptive chemistry surrounding these systems, and several …

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Algorithms And Complexity For Alliances And Weighted Alliances Of Various Types, Lindsay Jamieson May 2007

Algorithms And Complexity For Alliances And Weighted Alliances Of Various Types, Lindsay Jamieson

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The concept of alliances was introduced in 2002 in a paper by Kristiansen, Hedetniemi and Hedetniemi. Although research has been published on the mathematical properties of various types of alliances, until recently, no research has been done to develop algorithms or establish the complexity of decision problems for alliances in graphs.
This thesis presents the first algorithmic study of alliances in graphs. We present linear algorithms for finding various alliance numbers in trees and series parallel graphs. These linear algorithms are designed using a new methodology based on the well-established Wimer methodology for designing polynomial algorithms on k-terminal graphs. Linear …

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Functionalized Nanomaterials: Synthesis, Characterization, And Applications, Liangwei Qu May 2007

Functionalized Nanomaterials: Synthesis, Characterization, And Applications, Liangwei Qu

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Due to their unique electronic, optical, catalytic and mechanical properties, nanomaterials (nanoparticles and nanotubes) have been attracting much attention over the past decades. In this dissertation, polymeric nanoparticles bearing derivatized D-mannose and galactose molecules were prepared via dispersion polymerization and their interactions with various bacterial cells were studied. The results show that there are strong adhesin-specific interactions of the nanoparticles with E. coli cells, resulting significant nanoparticles-madiated cell agglutination.
Poly(ethylene glycol)-coated magnetic polymer nanoparticles were synthesized through miniemulsion polymerization by using macromonomer as both a comonomer and a surfactant. The resulting magnetic polymer nanoparticles were successfully used for bio-detection and …

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Extraction Method Development And In Vivo And In Vitro Toxicity Studies Of The Etiologic Agent Of Avian Vacuolar Myelinopathy, Faith Wiley May 2007

Extraction Method Development And In Vivo And In Vitro Toxicity Studies Of The Etiologic Agent Of Avian Vacuolar Myelinopathy, Faith Wiley

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Avian vacuolar myelinopathy (AVM) is a neurological disease affecting birds in the southeastern United States. The cause of the disease has not yet been determined but is believed to be a naturally produced toxin and is associated with aquatic vegetation. Current research on AVM is limited to in vivo studies utilizing whole tissue or vegetative samples. The objectives of this research were to develop extraction methods for isolating the putative AVM toxin from vegetative samples and to develop an in vitro bioassay for detection and study of the toxin. Samples of vegetation were collected from reservoirs known to be affected …

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Raman Spectroscopic Evidence For Anharmonic Phonon Lifetimes And Blueshifts In 1d Structures, Rahul Rao May 2007

Raman Spectroscopic Evidence For Anharmonic Phonon Lifetimes And Blueshifts In 1d Structures, Rahul Rao

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Anharmonic effects in two different quasi-1D systems were probed via micro-Raman spectroscopy. In the first system, we observed upshifts of peaks in the Raman spectra for b-Ga2O3 nanowires grown along the [110] growth direction compared those present in bulk b-Ga2O3. Contrary to our Raman studies on -Ga2O3 nanowires, downshifts in the Raman spectrum for b-Ga2O3 nanowires grown along [401] direction has also been reported by other research groups. We attribute these Raman shifts to the growth direction-induced lattice strains (compressive and tensile) present in the nanowires, and present a model based on the quasi-harmonic density functional theory to support our …

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Journey To Leadership: Women Administrators In Architecture, Margaret Woosnam May 2007

Journey To Leadership: Women Administrators In Architecture, Margaret Woosnam

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Of the 114 accredited architecture programs within colleges and universities across America, only 18 (or 16%) employ females at the highest administrative positions as deans, directors, chairs, or heads. Despite this statistic, nearly 50% of all graduates from architecture programs are female. Little is known about women administrators in architectural education, perhaps because of the fact that there are so few.
The central question that guided this research study is as follows: What personal and professional factors characterize 10 women employed as administrators in nationally accredited architecture programs, departments, schools, and colleges in American institutions of higher education? Additionally, this …

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Three Essays In Political Economy, Melissa Yeoh May 2007

Three Essays In Political Economy, Melissa Yeoh

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The first essay provides a theoretical framework that informs the ongoing debate regarding the effect of conservation easement subsidies on local property tax revenue. Supporters claim that conservation easements increase property tax revenue by providing environmental amenities that increase the value of adjacent properties. Critics argue that they decrease property tax revenue by lowering land values and shrinking the tax base. In instances when local property tax revenue decline due to the income tax deductibility of conservation easements, the decline is larger when the demand for land is more elastic, the proportion of non-agricultural land in the county is larger, …

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Meaningful Learning At A National Historic Site: How Interpretive Tour Message Content Affects Visitor Learning Transfer, Christine Van Winkle May 2007

Meaningful Learning At A National Historic Site: How Interpretive Tour Message Content Affects Visitor Learning Transfer, Christine Van Winkle

All Dissertations

This study examines meaningful learning transfer at a historic site. Transfer is the ability to apply knowledge to a new situation or setting and can be divided into near and far transfer. Near transfer is characterized by the ability to transfer knowledge to a similar situation, whereas far transfer is the ability to transfer knowledge to a different situation. This between-subject post-test only field experiment investigated the effect of interpretive message design on visitors' ability to transfer leaning from an interpretive audio tour at a heritage site. Interpretive messages were designed to examine the effect of message organizers (i.e. presence …

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Analysis Of Nutraceuticals For Toxic Metals: Development And Validation Of Sample Preparation Method, Julia Cooper May 2007

Analysis Of Nutraceuticals For Toxic Metals: Development And Validation Of Sample Preparation Method, Julia Cooper

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With increasing numbers of health-conscious consumers purchasing nutraceutical supplements, total sales in the nutrition industry have soared to over $200 billion in 2006. It is important to assess the safety of these nutraceutical products, with specific regards to toxic metals, including arsenic, cadmium, lead, and mercury. Because species of these metals may be more toxic than others, they can have hazardous health effects if ingested in excess quantities. The work described in this thesis focuses on the development of a sample preparation method for nutraceutical products, specifically ethanolic tinctures and glycerin-based matrices, and analysis of these products by inductively coupled …

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Energy Absorption Of Sine Wave Beams Subjected To Axial Impact Loading, Robert Smith May 2007

Energy Absorption Of Sine Wave Beams Subjected To Axial Impact Loading, Robert Smith

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Energy absorbers ideally remove kinetic energy efficiently and reliably while minimizing force magnitudes felt on the moving body. Until now, energy absorber design has concentrated on thin-walled prismatic tubes and tapered tubes. Sine wave beams (SWB) have been previously investigated as energy absorbers under lateral impacting situations only. This thesis investigates the energy absorption of the SWB under axial impact. FE models simulated the energy absorbing response of the SWB. Parametric analyses were performed using the structure's thickness, the web amplitude, and the period number of the web. The SWB's performance is evaluated and then compared to the prismatic structures. …

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Real Time Prognostic Strategies Application To Gas Turbines, Rajat Sekhon May 2007

Real Time Prognostic Strategies Application To Gas Turbines, Rajat Sekhon

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Gas turbines are increasingly deployed throughout the world to provide electrical and mechanical power in consumer and industrial sectors. The efficiency of these complex multi-domain systems is dependant on the turbine's design, established operating envelope, environmental conditions, and maintenance schedule. A real-time health management strategy can enhance overall plant reliability through the continual monitoring of transient and steady-state system operations. The availability of sensory information for control system needs often allow diagnostic/prognostic algorithms to be executed in a parallel fashion which warn of impending system degradations. Specifically, prognostic strategies estimate the future plant behavior which leads to minimized maintenance costs …

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Limbustrack: Stable Eye-Tracking In Imperfect Light Conditions, Wayne Ryan May 2007

Limbustrack: Stable Eye-Tracking In Imperfect Light Conditions, Wayne Ryan

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We are aware of only one serious effort at development of a cheap, accurate, wearable eye tracker: the open source openEyes project. However, its method of ocular feature detection is such that it is prone to failure in variable lighting conditions. To address this deficiency, we have developed a cheap wearable eye tracker. At the heart of our development are novel techniques that allow operation under variable illumination.

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Linear And Non-Linear Control Of A Quadrotor Uav, Andrew Neff May 2007

Linear And Non-Linear Control Of A Quadrotor Uav, Andrew Neff

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This thesis describes two controllers designed specifically for a quadrotor helicopter unmanned aerial vehicle (UAV). A linear controller and a non-linear controller are discussed for use on the quadrotor helicopter using feedback that is obtained from microelectromechanical systems and GPS.
The linear controller is an orientation based PID controller that controls the angles of the quadrotor UAV. The controller was first simulated and the results displayed graphically using FlightGear. Experiments were conducted using this controller on a DraganFlyer X-Pro quadrotor helicopter to prove the proposed method used for closing the feedback loop.
The non-linear controller is developed using Lyapunov stability …

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Modeling Requirements Propagation To Generate Solutions For Minimizing Mass, Thulasiram Ezhilan May 2007

Modeling Requirements Propagation To Generate Solutions For Minimizing Mass, Thulasiram Ezhilan

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This thesis investigates the issue of weight reduction in moderately complex systems by addressing how to cascade the requirements to the individual components. Though mass can be reduced using different techniques such as material substitution or structural optimization; a systematic method for allocating mass as a function of requirements is necessary to provide novel alternate solutions that enable reduction of mass of the system while satisfying the requirements and tests governing them. Such a method can be developed by exploring different aspects of achieving weight reduction through change propagation in the parameters/elements governing the system. Though efforts have been made …

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Design Of A Controller For A Precision Positioning Machine, Joshua Tarbutton May 2007

Design Of A Controller For A Precision Positioning Machine, Joshua Tarbutton

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System identification was used to build an accurate model of a high-precision measurement system. The model built by system identification was compared to modeling by first laws and showed extremely similar results. Pole-placement control design based on the identified system was used to place the systems' dominant poles. The necessary gains to achieve the desired system response were determined by using the identified model and knowledge of the controller structure. The performance of the model-based controller was compared to actual data of the system and showed that control based on the identified model can be used to accurately control the …

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Isomap Tracking With Particle Filter, Nikhil Rane May 2007

Isomap Tracking With Particle Filter, Nikhil Rane

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The problem of tracking an object in an image sequence involves challenges like translation, rotation, scaling, varying ambient light and occlusions. A model of an object is built off-line by making a training set with images of the object with different poses. A dimensionality reduction technique is used to capture the variations in the training images. This gives a low-dimensional representation of the data. Isometric feature mapping is the dimensionality reduction technique used to capture the true degrees of freedom in the data. Once the data is reduced to low-dimensions it forms a part of the state-vector of the object. …

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The Effects Of Gaze Guidance On Educational Software, Brian Murphy May 2007

The Effects Of Gaze Guidance On Educational Software, Brian Murphy

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There are currently three main kinds of eye tracking applications: gaze-responsive, gaze-aware, and gaze-contingent. A fourth classification, termed gaze-guiding, to our knowledge, coined and implemented for the first time. The gaze-guiding technique is the use of motion, light, color, or other visual stimuli to modify the user's fixation to predetermined locations when the user fixates on specific areas of interest. To test the technique, an education software program that teaches physics through the use of gaze-guidance was developed. It is suggested that a natural mapping exists between gaze-guidance and the software's built-in lesson plan. It is also speculated that gaze-guidance …

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Keck Hires Spectroscopy Of Candidate Post T Tauri Stars, Eric Bubar May 2007

Keck Hires Spectroscopy Of Candidate Post T Tauri Stars, Eric Bubar

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This work utilizes an age-oriented method to identify isolated post T Tauri stars in a 13-star sample of high resolution spectroscopy from the 10-m Keck telescope. This analysis utilizes qualitative age information derived from lithium abundances, chromospheric emission indices and UVW kinematic motions in analyzing positions in the the H-R diagram. Once qualitatively assigned a ``young'' age, pre-main sequence isochrones are utilized to determine stellar mass and age estimates. Through this method, 5 of the 13 stars have been confirmed as being in the post T Tauri class. We also examine irregular photometric variability of PTTs and compare the homology …

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Temperature Control Of An Air Shower, Vedik Bobba May 2007

Temperature Control Of An Air Shower, Vedik Bobba

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Accuracy and repeatability in measurement is a primary concern in improving and maintaining the quality of a product in an industry. In the case of coordinate measuring machines, these factors are affected due to the ambient conditions. Specifically, change in temperature affects machine geometry and causes positioning errors. As a result, temperature and humidity control inside the housing has become an important and integrated concern of measuring machine. This research concentrates on the modeling, design, control and validation of an air shower to meet a 20 ± 0.1 ¼C specification.
The optimum performance of the control of temperature of air …

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