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Graduate Theses, Dissertations, and Problem Reports (ETD)

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Numerical Simulation Of Continuous Miner Rock Cutting Process, Bo Yu May 2005

Numerical Simulation Of Continuous Miner Rock Cutting Process, Bo Yu

Graduate Theses, Dissertations, and Problem Reports (ETD)

Usually, parametric analysis of the continuous miner cutting process is studied by experimental tests. In this dissertation, the need for numerical simulation of the continuous miner rock cutting process is established. In order to fulfill this need, four major numerical methods, namely the Finite Difference Method, the Finite Element Method, the Boundary Element Method, and the Discrete Element Method, are reviewed. The Finite Element Method is then chosen as the simulation tool because it is more advanced and versatile than the other methods.;The rotation and advance of a continuous miner cutter head is simulated by the Finite Element Method with …

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Localized Double-Quantum Filtered Correlated Spectroscopy On 3t Mri/Mrs Scanner, Senthil Ramamurthy May 2005

Localized Double-Quantum Filtered Correlated Spectroscopy On 3t Mri/Mrs Scanner, Senthil Ramamurthy

Graduate Theses, Dissertations, and Problem Reports (ETD)

Standard localized magnetic resonance spectroscopic sequences employ single quantum coherences for excitation and detection. This results in a complex spectra containing large number of resonances. In this thesis we have developed a novel volume localized spectroscopic technique that excites multiple quantum coherences in coupled spin clusters (metabolites) and then reconvert them into single quantum coherences for detection. This results in filtering of uncoupled resonances and also suppresses water with high efficiency. The resulting spectra is reduced in complexity due to the absence of uncoupled resonances.;The technique has been developed in volume localized mode and implemented on a 3T scanner. The …

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Analysis And Synthesis Of Iris Images, Sarvesh Makthal May 2005

Analysis And Synthesis Of Iris Images, Sarvesh Makthal

Graduate Theses, Dissertations, and Problem Reports (ETD)

Of all the physiological traits of the human body that help in personal identification, the iris is probably the most robust and accurate. Although numerous iris recognition algorithms have been proposed, the underlying processes that define the texture of irises have not been extensively studied. In this thesis, multiple pair-wise pixel interactions have been used to describe the textural content of the iris image thereby resulting in a Markov Random Field (MRF) model for the iris image. This information is expected to be useful for the development of user-specific models for iris images, i.e. the matcher could be tuned to …

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Preparation Of Acoustic Emission Data For Neural Network Analysis Using Awk And C Programs, Avinash Kaza May 2005

Preparation Of Acoustic Emission Data For Neural Network Analysis Using Awk And C Programs, Avinash Kaza

Graduate Theses, Dissertations, and Problem Reports (ETD)

Fiber Reinforced Polymer composites are relatively new to the bridge construction industry. One of the challenges to greater usage is the lack of a real-time nondestructive method to accurately evaluate them. A Neural Network program can be used to predict the status of a structure by analyzing summarized Acoustic Emission data from the structure in real-time.;Existing methods use tools such as MS Excel to extract the Neural Network input matrix from raw data having more than 30,000 rows of Acoustic Emission data for a simple three point bending test. This manual data extraction process is very time consuming. Therefore, application …

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Noise And Error Propagation In Diffusion Tensor Imaging, Shital Bipin Desai May 2005

Noise And Error Propagation In Diffusion Tensor Imaging, Shital Bipin Desai

Graduate Theses, Dissertations, and Problem Reports (ETD)

Diffusion Tensor Imaging (DTI) is the in vivo visualization and analysis of white matter fiber tracts by measuring the anisotropy of water molecule diffusion in the brain tissue. DTI has been increasingly used in clinical imaging. Diffusion weighted images are affected by noise from the human subject and the MRI scanner. This thesis studies the error propagation in the calculation of the DTI invariant anisotropy, mainly the Fractional Anisotropy (FA) using four methods and their comparison in terms of error, filtering and computational efficiency using simulated and human brain data. These methods were Diffusion Tensor, Diffusion Ellipsoid, Hasan and Platonic …

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Computer-Assisted Learning Of Japanese Kanji, Adam D. Horne May 2005

Computer-Assisted Learning Of Japanese Kanji, Adam D. Horne

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of the program described in this problem report is to assist learners of Japanese kanji in remembering the order, direction, and number of strokes for a given kanji. Using OpenGL and the Open Haptics toolkit, the program allows the user to both see and feel the kanji. Using a PHANTOM haptic device, the user can trace the different strokes using a height map of the kanji or following arrows that show the direction and order of strokes.

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Text-Independent Speaker Recognition, Smitha Gangisetty May 2005

Text-Independent Speaker Recognition, Smitha Gangisetty

Graduate Theses, Dissertations, and Problem Reports (ETD)

This research presents new text-independent speaker recognition system with multivariate tools such as Principal Component Analysis (PCA) and Independent Component Analysis (ICA) embedded into the recognition system after the feature extraction step. The proposed approach evaluates the performance of such a recognition system when trained and used in clean and noisy environments. Additive white Gaussian noise and convolutive noise are added. Experiments were carried out to investigate the robust ability of PCA and ICA using the designed approach. The application of ICA improved the performance of the speaker recognition model when compared to PCA. Experimental results show that use of …

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Design, Construction And Initial Testing Of Experimental Test Package For Convective Spray Cooling In Terrestrial Gravity Conditions, Charles Andy Hunnell May 2005

Design, Construction And Initial Testing Of Experimental Test Package For Convective Spray Cooling In Terrestrial Gravity Conditions, Charles Andy Hunnell

Graduate Theses, Dissertations, and Problem Reports (ETD)

The design and construction of an apparatus for spray cooling tests was completed to better understand the effects of spray cooling with different geometries at varied flow rates and different spray orientations. Three different geometries were studied at four different spray volumetric flow rates varying from 9.3 GPH to 4.6 GPH. At each spray flow rate the heat flux of the small heated pedestal located in the spray chamber was increased from 5 W/cm2 to 32.24 W/cm2. During these tests the spray orientation was changed from a vertical downward spray to a horizontal spray. The convective heat transfer coefficient and …

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Forced Vibration And Hygrothermal Analysis Of Composite Laminated Beams Under The Action Of Moving Loads, Praveen Kumar Kavipurapu May 2005

Forced Vibration And Hygrothermal Analysis Of Composite Laminated Beams Under The Action Of Moving Loads, Praveen Kumar Kavipurapu

Graduate Theses, Dissertations, and Problem Reports (ETD)

The dynamic response of simply supported glass/epoxy composite beams subjected to moving loads in a hygrothermal environment is carried out using the general purpose finite element program ANSYS. The moving load model and the hygrothermal incorporation are validated separately by reproducing results available in the literature. The hygrothermal effect is introduced by using empirical relations for degrading the material stiffness properties of the matrix. The corresponding ply properties are calculated using the rule of mixtures. A parametric study is conducted by varying the fiber volume fraction and the fiber orientation of the angle plies in the laminate. The results indicate …

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Effect Of Opening Size On The Effectiveness Of A Noise Enclosure On The Side Facing The Opening, Amit Damodar Hegde May 2005

Effect Of Opening Size On The Effectiveness Of A Noise Enclosure On The Side Facing The Opening, Amit Damodar Hegde

Graduate Theses, Dissertations, and Problem Reports (ETD)

Noise enclosures are an important tool in reducing noise exposures. Holes in enclosures are known to reduce the effectiveness of such enclosures. There are methods to predict the effects of openings, but those methods are largely untested in real enclosures. This study investigated the effects of hole size (0%, 0.024%, 0.379%, 0.675%, 1.492%,and 5.063%) at a distance of 5 feet (1.524 m) in a 96 inch (2.46 m) x 37 inch (0.94 m) x 31 inch (0.79 m), 3/4 inch plywood enclosure with a noise source centered in the box and the openings centered on one long face of the …

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Methodology To Determine Post Yield Material Mechanical Properties From Spherical Indentation, Bharath Konda May 2005

Methodology To Determine Post Yield Material Mechanical Properties From Spherical Indentation, Bharath Konda

Graduate Theses, Dissertations, and Problem Reports (ETD)

Conventional material testing methods, such as tensile tests require the preparation of specimens and is not applicable for small-size coupons or on-site, in-situ testing. In this research, a method of determining material stress-strain curve based on spherical indentation is studied. Spherical-indentation process is analyzed by finite element (FE) method and a systematic analysis of relationships between indentation parameters and true stress/plastic-strain (sigmat- epsilonp) curve is performed for a range of material properties. A detailed methodology based on Tabor's empirical formula and Meyer's law is developed to determine the material strain hardening properties, Young's modulus and yield strength. It is noticed …

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Schemas, Jennifer G. Yerdon May 2005

Schemas, Jennifer G. Yerdon

Graduate Theses, Dissertations, and Problem Reports (ETD)

The work included in my MFA thesis exhibition entitled Schemas, represent the relationship that objects have to the body via perception. They become a map of understanding that is at once the object and the experience of that things objectness. Strategically composed this experience is translated into texture, color, and pattern. In this thesis statement I will address how we understand objects in the world and the importance of our interaction with said objects. In addition I will discuss the map like processes that I employ to create these works. I will also discuss the influential artists and writing that …

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Measurement And Evaluation Of The Performance Of An Integral Abutment Bridge Deck, Kenneth Mcgowan May 2005

Measurement And Evaluation Of The Performance Of An Integral Abutment Bridge Deck, Kenneth Mcgowan

Graduate Theses, Dissertations, and Problem Reports (ETD)

This thesis is based upon the instrumentation of an integral abutment bridge, with a reinforced concrete deck on 3-span, continuous steel girders. The bridge is located in Evansville, West Virginia, at the intersection of WV Route 92 South and US Route 50 East. An instrumentation system was developed to measure the performance of the bridge, including a system of 30 crack meters installed in the deck to detect cracks, strain gages on the girders and embedded in the deck, whose readings can be utilized to determine the degree of composite action of the deck and girders, and sister bars to …

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Multi-Resolution Dental Image Registration Based On Genetic Algorithm, Mythili Ogirala May 2005

Multi-Resolution Dental Image Registration Based On Genetic Algorithm, Mythili Ogirala

Graduate Theses, Dissertations, and Problem Reports (ETD)

The Automated Dental Identification System (ADIS) is a Post Mortem Dental Identification System. This thesis presents dental image registration, required for the preprocessing steps of the image comparison component of ADIS. We proposed a multi resolution dental image registration based on genetic algorithms. The main objective of this research is to develop techniques for registration of extracted subject regions of interest with corresponding reference regions of interest.;We investigated and implemented registration using two multi resolution techniques namely image sub sampling and wavelet decomposition. Multi resolution techniques help in the reduction of search data since initial registration is carried at lower …

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Evaluation Of Superpave Mixtures In West Virginia Using The Asphalt Pavement Analyzer, Gabriel E. Patino May 2005

Evaluation Of Superpave Mixtures In West Virginia Using The Asphalt Pavement Analyzer, Gabriel E. Patino

Graduate Theses, Dissertations, and Problem Reports (ETD)

The Superpave mix design method is widely implemented in the Unites States. Fundamental tests have been developed to assess a pavement's distress; however, those tests are time-consuming and require special equipment. Simpler tests, such as wheel tracking devices, have been developed. The most common is the Asphalt Pavement Analyzer, APA, a loaded wheel tester method to evaluate rutting, moisture susceptibility, and fatigue cracking.;This research focused on establishing whether there are relationships between the APA rutting potential and field performance. The APA was used to measure the rutting potential of Superpave mixes constructed throughout the state. Then the WVDOH provided rutting …

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Analysis Of Red Spruce (Picea Rubens) Regeneration In Pocahontas, Randolph, And Tucker Counties, West Virginia, Adam W. Rollins May 2005

Analysis Of Red Spruce (Picea Rubens) Regeneration In Pocahontas, Randolph, And Tucker Counties, West Virginia, Adam W. Rollins

Graduate Theses, Dissertations, and Problem Reports (ETD)

Three red spruce communities in the Central Appalachians of West Virginia were accessed temporally over a period of 10 to 11 years and by forest zones (i.e. hardwood, ecotone, red spruce zones). These communities experienced an increasing density of red spruce over time across all forest zones. Red spruce was successfully establishing and expanding across the ecotone into the hardwood forest zone. The greatest increase of red spruce was seen in the more disturbed and earlier successional sites, whereas the less disturbed red spruce community experienced the least change. The red spruce populations in this study were thriving and increasing …

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Investigation Of Fabrication Process Development For Integrated Optical Grating Structures, Divya Pisharoty May 2005

Investigation Of Fabrication Process Development For Integrated Optical Grating Structures, Divya Pisharoty

Graduate Theses, Dissertations, and Problem Reports (ETD)

Sub-micron optical gratings are essential integrated elements to couple light into waveguides and for optical monitoring of microfluidic channels or MEMS devices. Since the required features in the sub-micron regime are difficult to achieve by mechanical ruling and photolithography, alternate fabrication techniques are investigated. Exposure by e-beam and laser are two direct write methods which are used. These methods preclude the need of a mask, require few processing steps, and can be used to write features of sizes desired for optical gratings. In this research, we explore and develop processes to create sub-micron gratings by both these methods. A resist …

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Fingerprint Testing Protocols For Optical Sensors, Travis W. Rosiek May 2005

Fingerprint Testing Protocols For Optical Sensors, Travis W. Rosiek

Graduate Theses, Dissertations, and Problem Reports (ETD)

Currently there is a variety of conflicting and contradictory testing protocols for biometric technologies. There is currently no biometrics testing standard, which allows vendors to skew their test results in their favor. The research discussed in this thesis aims to address these issues by developing and validating testing protocols for optical fingerprint sensors. Angle of rotation, translation, lighting, and device placement have been identified in this work as variables potentially affecting system performance and protocols were developed to evaluate their effects on optical fingerprint sensor performance. Testing was done by capturing raw images under different scenarios, then offline analysis of …

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Unbalanced Frame: A Content Analysis Of Four Main American Newspapers And Their Coverage Of Colombia And The Drug Issue., Olga Elena Velez Galvis Jan 2005

Unbalanced Frame: A Content Analysis Of Four Main American Newspapers And Their Coverage Of Colombia And The Drug Issue., Olga Elena Velez Galvis

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study used content analysis of The New York Times, Los Angeles Times, Miami Herald and Dallas Morning news and analyzed their coverage of Colombia and the drug issue during 1993, 1998 and 2003. The main purpose was to observe how these publications reported on this topic over that specific period of time. Findings showed prevalence of episodic stories over the thematic ones. These papers primarily presented episodic news coverage on Colombia and their drugs, which exhibited mainly a negative tone. On the other hand, thematic news coverage on Colombia and its drugs were more positive than the episodic, since …

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Hall Effect And Photoconductivity Lifetime Studies Of Gallium Nitride, Indium Nitride, And Mercury Cadmium Telluride., Craig H. Swartz Jan 2005

Hall Effect And Photoconductivity Lifetime Studies Of Gallium Nitride, Indium Nitride, And Mercury Cadmium Telluride., Craig H. Swartz

Graduate Theses, Dissertations, and Problem Reports (ETD)

A deep understanding of both carrier recombination and transport is necessary for semiconductor engineering, particularly in defining the ultimate limits of performance for a given device before spending the resources to perfect its fabrication. Hall effect measurements utilizing a variable magnetic field are necessary to discriminate between conduction in epitaxial layers and conduction originating at the surface or at an interfacial layer. For thick hydride vapor phase epitaxy (HVPE) grown GaN, variable field Hall measurements revealed the presence of small but significant lower mobility surface and interface electrons which would otherwise lead to errors in interpreting the electrical properties. In …

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A National Survey Of College Level Percussion Teachers Regarding The Importance Of Certain Characteristics Of Percussion Materials In Beginning Instrumental Methods., Ronald George Horner Jan 2005

A National Survey Of College Level Percussion Teachers Regarding The Importance Of Certain Characteristics Of Percussion Materials In Beginning Instrumental Methods., Ronald George Horner

Graduate Theses, Dissertations, and Problem Reports (ETD)

Teaching percussion instruments in elementary school settings presents unique challenges. Development of reading skills, musicality, technique, and listening skills are often cited as concerns. Materials selected by educators can facilitate or encumber the process. This study examined the characteristics of beginning methods materials from the perspective of college level percussion teachers. 269 teachers participated in a researcher-developed survey as a representative cross-section of institutions of higher learning including community colleges, baccalaureate institutions, and institutions with graduate programs. Results were analyzed from frequency distributions and manually generated stem-and-leaf plots. The survey examined respondent background and teaching experience, institutional information, and professional …

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The Efficient Dissemination Of Information In Highly Mobile Ad Hoc Networks., Michael Gorden Kirkpatrick Jan 2005

The Efficient Dissemination Of Information In Highly Mobile Ad Hoc Networks., Michael Gorden Kirkpatrick

Graduate Theses, Dissertations, and Problem Reports (ETD)

With the proliferation of wireless networked computing devices in recent years, the importance of communication between nodes in these networks has increased greatly. The mobility of these nodes complicates the problem because a given node's connections to the network are likely to change over time with the result that communication paths are established ad hoc. As the speed of the nodes increases or the computing power available to them is reduced, many standard techniques for predicting available message pathways no longer work. In these highly mobile ad hoc networks, the links between nodes can change between the time they are …

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Cytochrome P450 1a-Substrate Interactions: Determinants Of Substrate Selectivity And Stereo- And Regiospecificity Of Oxidation., Spencer Snyder Ericksen Jan 2005

Cytochrome P450 1a-Substrate Interactions: Determinants Of Substrate Selectivity And Stereo- And Regiospecificity Of Oxidation., Spencer Snyder Ericksen

Graduate Theses, Dissertations, and Problem Reports (ETD)

Cytochromes P450 comprise a ubiquitous superfamily of heme-thiolate enzymes, considered among the most versatile biological catalysts known. Structure-function relationships of P450s are of particular interest to those attempting to elucidate such aspects of xenobiotic metabolism as substrate selectivity and regiospecific oxidations. We studied two members of the P450 1A subfamily, P450 1A1 and 1A2, found in highest abundance in lung and liver tissues, respectively. These enzymes may have an important link to cancer, as both are known to regiospecifically activate procarcinogenic substrates. To gain a better understanding of structure-function relationships in these enzymes, we applied a combination of site-directed mutagenesis, …

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A Study Of Persuasion, Propaganda And The Effectiveness Of Messages., Kelly M. Saunders Jan 2005

A Study Of Persuasion, Propaganda And The Effectiveness Of Messages., Kelly M. Saunders

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study of persuasive and propagandistic messages explores the differences and similarities among the two, as well as elements necessary for success, using previous research in the field. In addition, this report includes an analysis of the diffusion, framing, placement within newspaper articles, and effects of news content relating to the Swift Boat Veterans for Truth disseminated during the 2004 Presidential campaign. The results of this study suggest a need for greater scrutiny among reporters regarding messages distributed by interest groups.

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An Attack-Resistant Approach To Vulnerability Scanner Design., David Phillip Shaver Jan 2005

An Attack-Resistant Approach To Vulnerability Scanner Design., David Phillip Shaver

Graduate Theses, Dissertations, and Problem Reports (ETD)

Vulnerability scanners are used to scan and detect known vulnerabilities in computer systems. An attacker can exploit these vulnerabilities to compromise the security of a system and potentially cause harm. Thus, it is vital to detect and repair any vulnerabilities that exist. Vulnerability scanners, however, are themselves susceptible to attack. If an attacker were to compromise a scanner, they could force it ignore the vulnerabilities of other systems. They could then compromise these other computers by exploiting the undetected vulnerabilities. Due to the importance of preventing such false positives in scan results, this research proposes a new approach to vulnerability …

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Assessment Of Nitrogen Oxide Destruction In Heavy-Duty Diesel Engines By Injecting Nitric Oxide Into The Intake., Ramprabhu Vellaisamy Jan 2005

Assessment Of Nitrogen Oxide Destruction In Heavy-Duty Diesel Engines By Injecting Nitric Oxide Into The Intake., Ramprabhu Vellaisamy

Graduate Theses, Dissertations, and Problem Reports (ETD)

Emissions from diesel engines, particularly oxides of nitrogen (NOx) and total particulate matter (TPM) emissions are harmful to the environment. Reduction of NOx emissions from diesel engines is of increasing concern. In 1998, a novel approach called Selective NOx Recirculation (SNR) was used to reduce NOx emissions in diesel engines. The SNR concept relies on two major parts, one to collect the NOx emissions from the exhaust using an adsorber, and another to decompose NOx using the in-cylinder combustion process by injecting the collected NOx emissions into the intake manifold at an elevated concentration. This research assesses the decomposition percentage …

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The Organ Music Of Robert Hebble (B.1934), John Paul Cappa Jan 2005

The Organ Music Of Robert Hebble (B.1934), John Paul Cappa

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this research project is to provide a stylistic and quasi-theoretical study of Robert Hebble's compositions for organ as a performer's guide. Hebble presently resides in Lake Worth, Florida. He is still composing, accepting commissions, writing articles, playing recitals, and giving workshops.;The organ music of Robert Hebble is a significant contribution to twentieth-century American organ literature. He has composed in various genres, from simple church service music to solo concert pieces. His organ compositions span his entire career and make use of a wide variety of techniques and styles.;Part I provides information about the composer's life. It discusses …

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Dynamics And Mechanism Studies Of Nonlinear Chemical Systems, Tabitha R. Chigwada-Razunguzwa Jan 2005

Dynamics And Mechanism Studies Of Nonlinear Chemical Systems, Tabitha R. Chigwada-Razunguzwa

Graduate Theses, Dissertations, and Problem Reports (ETD)

The kinetics and mechanisms of oxidation of selected thiocarbamides (tetra-methylthiourea, trimethylthiourea, phenylthiourea, and 2-aminoethanethiolsulfuric acid) by chlorite in aqueous acidic media are investigated using UV/Vis, NMR, Stopped-flow techniques, and qualitative analysis. The reactions were extremely complex, with reaction dynamics strongly influenced by the pH of the reaction medium and formation of stable intermediates (sulfonic acids). Results revealed that oxidations of substituted thioureas do not always proceed via a stepwise oxidation of the sulfur center. Instead, reactions occurred in two stages: S-oxygenation of the sulfur center to yield the sulfinic acid, which then reacts in the second phase predominantly through an …

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Measurements Based Performance Analysis Of Web Services, Venu Datla Jan 2005

Measurements Based Performance Analysis Of Web Services, Venu Datla

Graduate Theses, Dissertations, and Problem Reports (ETD)

Web services are increasingly used to enable interoperability and flexible integration of software systems. In this thesis we focus on measurement-based performance analysis of an e-commerce application which uses Web services components to execute business operations. In our experiments we use a session-oriented workload generated by a tool developed accordingly to TPC-W specification. The empirical results are obtained for two different user profiles, Browsing and Ordering, under different workload intensities. In addition to variation in workloads we also study the applications performance when Web services are implemented using .NET and J2EE. Unlike the previous work which was focused on the …

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Energy-Sensitive Machining Parameter Optimization Model, Deepak Prakash Gupta Jan 2005

Energy-Sensitive Machining Parameter Optimization Model, Deepak Prakash Gupta

Graduate Theses, Dissertations, and Problem Reports (ETD)

Manufacturing industries are one of the most important elements in the economic growth and stability of any country. It is very important that the process parameters are given proper attention to maximize the value addition and increased profits for these industries. Parameter optimization for different manufacturing processes has been a challenging and interesting problem in the past. Many researchers have studied the problem of optimizing the process parameters for the turning process. In all the cases studied so far, no one has considered the significance of energy required and its cost for the machining process as an integral part of …

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