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A Study Of Ion Acceleration, Asymmetric Optical Pumping And Low Frequency Waves In Two Expanding Helicon Plasmas, Xuan Sun
Graduate Theses, Dissertations, and Problem Reports
This work concerns measurements of parallel ion flow, optical pumping, and low frequency waves in expanding plasmas generated by two different helicon plasma sources. The measurements confirm numerical predictions of the formation of a current-free double layer in a region of diverging magnetic field. With laser-induced fluorescence (LIF), the double layer structure in both helicon plasma sources was investigated through measurements of the bulk parallel ion flow speed. Both double layers have a total potential drop of 3-4 kTe and length scales smaller than ion-neutral mean-free-path. A stronger double layer, with a potential drop of ∼ 6kTe , was created …
Psychological Readiness: Is This Assessment Valuable To Athletic Trainers In Understanding Athletes' Adherence And Compliance, Damien Clement
Psychological Readiness: Is This Assessment Valuable To Athletic Trainers In Understanding Athletes' Adherence And Compliance, Damien Clement
Graduate Theses, Dissertations, and Problem Reports
Despite the many documented psychological reactions athletes experiences as a result of athletic injuries, very little, if any psychological assessment is being done to evaluate their readiness to embark on their rehabilitation. Consequently, the purpose of this study was to determine if psychological readiness influences athletes' adherence and compliance to their rehabilitation programs. A secondary purpose was to determine the impact psychological readiness had on perceived versus actual completion rates of rehabilitation programs. Injured college student athletes' (N=70) psychological readiness were assessed (using the transtheoretical model of behavior change 10) to determine its effect on compliance, adherence rates and perceived …
Small Particle Separation In A Circulating Fluidized Bed Riser System, Robert R. Almond
Small Particle Separation In A Circulating Fluidized Bed Riser System, Robert R. Almond
Graduate Theses, Dissertations, and Problem Reports
Particle separation is an important area of interest in many fields, such as the coal and mineral processing industries. A circulating fluidized bed riser system has been built to investigate the separation processes. The system separated the particles into three streams which lead to the dense bin, the product bin, and the filter chamber. Promising results have been obtained which may lead to a system which is viable for commercial separation. The following categories of separation were investigated: separation based on size difference of the particles, separation based on density difference of the particles, and the practicality of separating mineral …
Laser-Induced Breakdown Spectroscopy As A Diagnostic Tool For Coal Fines, I. Andrew Aurelio
Laser-Induced Breakdown Spectroscopy As A Diagnostic Tool For Coal Fines, I. Andrew Aurelio
Graduate Theses, Dissertations, and Problem Reports
Laser Induced Breakdown Spectroscopy (LIBS) is a technique that uses a laser, to focus down and atomize a sample of desired material. Focusing of the laser onto the material causes a plasma formation, which the material is broken down into excited ionic and atomic states. The atoms then emit characteristic optical radiation. Collection of the emitted light can be used to provide information on the elemental composition of the material. This research investigates a fundamental study of laser-induced breakdown spectroscopy (LIBS) applied to coal samples, coal fines, and fly ash. During this research, apparatus and methodology were developed to quantify …
Effectiveness Of The "Common" Method In Balancing Exhaust Ventilation Systems, Vivek Balasubramanian
Effectiveness Of The "Common" Method In Balancing Exhaust Ventilation Systems, Vivek Balasubramanian
Graduate Theses, Dissertations, and Problem Reports
Dampers are used to adjust the distribution of airflows in duct systems. The "common"(i.e., most commonly used) method is to adjust each damper in turn so that the airflow through its branch equals the desired level. Typically, the airflow through each branch duct is estimated from the centerline velocity pressure. To test the effectiveness of that approach, dampers were adjusted on a seven branch, full-sized experimental duct system. After adjusting the dampers for a given condition, the percent excess airflow (%Qexcess) for the system was estimated as the amount above the ideal fan airflow that would exist if the fan …
Characterization And Investigation Of Molybdenum Carbides On Activated Carbon As Hydrogenation Catalysts, Christopher H. Clark
Characterization And Investigation Of Molybdenum Carbides On Activated Carbon As Hydrogenation Catalysts, Christopher H. Clark
Graduate Theses, Dissertations, and Problem Reports
The formation of Mo2C and MoC supported on activated carbon was investigated in three different flowing reaction gas environments: H2, He, and CO. Additionally, benzene hydrogenation activity was studied for the catalysts reduced in each of these three different gas environments.;It was found through in-situ x-ray diffraction (XRD) that reducing in H2, ammonium heptamolybdate impregnated on activated carbon yielded 1-3 nm Mo2C particles. When the same material was calcinced in inert, 9 nm Mo2C particles were formed. If the reduction gas were CO, MoC particles having size less than 3 nm were formed. In all three reduction environments, the in-situ …
Non-Ideal Iris Recognition, Vivekanand Dorairaj
Non-Ideal Iris Recognition, Vivekanand Dorairaj
Graduate Theses, Dissertations, and Problem Reports
Of the many biometrics that exist, iris recognition is finding more attention than any other due to its potential for improved accuracy, permanence, and acceptance. Current iris recognition systems operate on frontal view images of good quality. Due to the small area of the iris, user co-operation is required. In this work, a new system capable of processing iris images which are not necessarily in frontal view is described. This overcomes one of the major hurdles with current iris recognition systems and enhances user convenience and accuracy. The proposed system is designed to operate in two steps: (i) preprocessing and …
Image Quality Assessment For Iris Biometric, Nathan D. Kalka
Image Quality Assessment For Iris Biometric, Nathan D. Kalka
Graduate Theses, Dissertations, and Problem Reports
Iris recognition, the ability to recognize and distinguish individuals by their iris pattern, is the most reliable biometric in terms of recognition and identification performance. However, performance of these systems is affected by poor quality imaging. In this work, we extend previous research efforts on iris quality assessment by analyzing the effect of seven quality factors: defocus blur, motion blur, off-angle, occlusion, specular reflection, lighting, and pixel-counts on the performance of traditional iris recognition system. We have concluded that defocus blur, motion blur, and off-angle are the factors that affect recognition performance the most. We further designed a fully automated …
Optical Detection Of Multiple Faults Of A Mems Based Linear Comb Resonator, Lakshmi Deepasree Konduparthi
Optical Detection Of Multiple Faults Of A Mems Based Linear Comb Resonator, Lakshmi Deepasree Konduparthi
Graduate Theses, Dissertations, and Problem Reports
Investigating the dynamic behavior of any Micro Electro Mechanical system is critical for better control and fault prediction. Linear Comb Resonator is one such MEMS generic device that exhibits motion parallel to the plane of the chip. The dynamic motion of the Linear Comb Resonator is characterized by various parameters such as mass, force applied and also the stiffness constant of the flexure that holds the device. The aim of the project is to determine the changes caused by the asymmetry in the flexure design and the fluctuations in the behavior of the resonator due to this. The changes in …
Carbon Fuels For The Direct Carbon Fuel Cell, Abha Saddawi
Carbon Fuels For The Direct Carbon Fuel Cell, Abha Saddawi
Graduate Theses, Dissertations, and Problem Reports
This research focuses on using the U.S.' abundant coal reserves to create carbon fuels for the production of energy in a very efficient and environmentally friendly manner via the use of a Direct Carbon Fuel Cell (DCFC). This cell utilizes a process by which carbon is electrochemically converted directly to electricity, allowing theoretical cell efficiency to approach 80%. Using carbon made from the solvent extraction of coal eliminates most of the volatiles, ash, and sulfur from the fuel while most of the remaining NOX, sulfur, and fly-ash byproducts are captured by the cell itself. The aim of this project is …
Error And Attack Tolerance Of Complex Real Networks, Vamsi Salla
Error And Attack Tolerance Of Complex Real Networks, Vamsi Salla
Graduate Theses, Dissertations, and Problem Reports
Real networks are often subjected to failures and attacks. Real networks are found to be robust to errors and vulnerable to attacks. This behavior of real networks is attributed to their non-homogeneous degree distribution. Non-homogenous networks are also known as scale free networks. Real networks along with the scale free property show high modularity.;Many network models have been proposed to model real networks. Erdos-Renyi Random network model is the first attempt, but fails to incorporate both properties - scale free as well as the high modularity of the real networks. Small world model shows high clustering but lacks non-homogeneous distribution. …
Empirical Study Of Error Behavior In Web Servers, Ajay Deep Singh
Empirical Study Of Error Behavior In Web Servers, Ajay Deep Singh
Graduate Theses, Dissertations, and Problem Reports
The World Wide Web has been a huge success, bringing the Internet to widespread popularity. For Web based systems to deal effectively with increasing number of Web clients, it is very important to understand the basic fundamentals of Web workload and error characteristics. In this thesis we focus on detailed empirical analysis of Web server error characteristics and reliability based on the data extracted from eleven different web servers. First, we address the data collection process and describe the methods for extraction of workload and error data from Web logs. Then, we analyze the Web error characteristics which include unique …
Ensemble Learning For Ranking Interesting Attributes, Erik W. Sinsel
Ensemble Learning For Ranking Interesting Attributes, Erik W. Sinsel
Graduate Theses, Dissertations, and Problem Reports
Machine learning knowledge representations, such as decision trees; are often incomprehensible to humans. They can also contain errors specific to the representation type and the data used to generate them. By combining larger; less comprehensible decision trees, it is possible to increase their accuracy as an ensemble compared to the best individual tree. The thesis examines an ensemble learning technique and presents a unique knowledge elicitation technique which produces an ordered ranking of attributes by their importance in leading to more desirable classifications. The technique compares full branches of decision trees, finding the set difference of shared attributes. The combination …
Prosody In Text-To-Speech Synthesis Using Fuzzy Logic, Jonathan Brent Williams
Prosody In Text-To-Speech Synthesis Using Fuzzy Logic, Jonathan Brent Williams
Graduate Theses, Dissertations, and Problem Reports
For over a thousand years, inventors, scientists and researchers have tried to reproduce human speech. Today, the quality of synthesized speech is not equivalent to the quality of real speech. Most research on speech synthesis focuses on improving the quality of the speech produced by Text-to-Speech (TTS) systems. The best TTS systems use unit selection-based concatenation to synthesize speech. However, this method is very timely and the speech database is very large. Diphone concatenated synthesized speech requires less memory, but sounds robotic. This thesis explores the use of fuzzy logic to make diphone concatenated speech sound more natural. A TTS …
Unconstrained Face Recognition For Law Enforcement Applications, Richa Singh
Unconstrained Face Recognition For Law Enforcement Applications, Richa Singh
Graduate Theses, Dissertations, and Problem Reports
This research work simulates the human visual cortex by using 2D log polar Gabor wavelet to extract the facial features. Scale and orientation independent convolution of face image with Gabor wavelet gives the features in the form of amplitude and phase. The proposed face recognition algorithm is invariant to frequency, scale, filter orientation, illumination, and contrast. We evaluated the recognition algorithm on four face databases namely FERET, CMU AMP, CMU PIE and Notre Dame Face databases. Experimental results show that using single image for training, phase feature based face recognition performs approximately 5% better than amplitude feature based face recognition.;Another …
Reducing False Rejection Rate In Iris Recognition By Quality Enhancement And Information Fusion, Mayank Vatsa
Reducing False Rejection Rate In Iris Recognition By Quality Enhancement And Information Fusion, Mayank Vatsa
Graduate Theses, Dissertations, and Problem Reports
In this thesis we propose a set of algorithms to reduce the false rejection rate of iris recognition. Even though high recognition accuracy is claimed for iris recognition algorithms, high false rejection rates cause the impediment in worldwide use of iris biometrics.;A novel iris segmentation algorithm for non-ideal iris images treating iris as an elliptical object is proposed. Further, quality of the extracted iris image is improved using SVM based enhancement algorithm. In this algorithm, selected enhancement algorithms globally enhance the iris image and the learning algorithm synergistically fuses local information from these intermediate enhanced images. 1D log polar Gabor …
Real-Time Measurements Of Space Potential In Magnetized Plasma Using A Baffled Langmuir Probe, Sean M. Finnegan
Real-Time Measurements Of Space Potential In Magnetized Plasma Using A Baffled Langmuir Probe, Sean M. Finnegan
Graduate Theses, Dissertations, and Problem Reports
An electrostatic probe for real-time measurements of space potential in magnetized plasma is tested in fully ionized, barium, Q-machine plasma. The tungsten wire probe tip, oriented perpendicular to the magnetic field, is partially shielded by ceramic baffles (masks). Rotation of the probe about its cylindrical axis, changes the fraction of electrons that can reach the probe tip along the magnetic field, enabling the ratio between the electron and ion saturation currents to be adjusted without changing the probe bias. When optimally shielded, accurate, real-time measurements of space potential can be acquired.
Parents' Perceptions Of The Gluten-Free Casein-Free Diet For Their Children With Autism, Annette Puglisi
Parents' Perceptions Of The Gluten-Free Casein-Free Diet For Their Children With Autism, Annette Puglisi
Graduate Theses, Dissertations, and Problem Reports
This study examined the factors that affected parent's decision for putting their autistic children on a gluten free casein free diet (gfcf diet). Parents completed a fifteen question survey relating to multiple factors affecting their lives while having their children on a gfcf diet. In addition, parents were asked to fill out a three day diet history for their child for a nutrient analysis.;Fifty three surveys (21%) and ten diet histories were returned. The majority of parents first heard of the gfcf diet either on the Internet (28%) or from Parent Magazine (32%). Desperation (25%) was the main reason parents …
Temporal Trends In Consumption, Growth, And Successful Feeding Traits Of A Central Appalachian Brook Trout Population At The Watershed Scale, Ryan Michael Utz
Temporal Trends In Consumption, Growth, And Successful Feeding Traits Of A Central Appalachian Brook Trout Population At The Watershed Scale, Ryan Michael Utz
Graduate Theses, Dissertations, and Problem Reports
Brook trout (Salvelinus fontinalis) in Appalachia frequently experience limitations in food availability. In order to determine temporal variation in consumption, successful feeding, and corresponding population patterns and growth, the feeding dynamics of a population of brook trout were monitored throughout a headwater watershed over the course of two years. The Middle Fork River brook trout experienced food limitation throughout summer and fall, however, mean consumption estimates fell below maintenance ration only during the winter seasons. Consumption estimates were significantly related to watershed position, as fish in low density, downstream reaches consistently consumed significantly more energy than fish upstream during warm …
Factors Affecting Reproductive Efficiency Of Cattle, Melanie J. Starbuck
Factors Affecting Reproductive Efficiency Of Cattle, Melanie J. Starbuck
Graduate Theses, Dissertations, and Problem Reports
Four experiments were conducted to evaluate two measures of reproductive efficiency in cattle, conception rate and retention of pregnancy. In experiment I, the relationship between concentrations of progesterone and retention of pregnancy was examined. The corpus luteum (CL) was removed on day 29 of pregnancy in 40 suckled, beef cows, and pregnancy was supported with exogenous progesterone to day 53. Concentrations of progesterone (1.8 +/- 0.1 ng/mL between days 30 and 38), were below those normally recorded for pregnant cows. Retention of pregnancy (77%) was monitored frequently using ultrasonography until day 53 and was negatively associated with age of cow, …
Synthesis Of Novel Alkaloids Using Squaric Acid Esters, Peter S. Zehr
Synthesis Of Novel Alkaloids Using Squaric Acid Esters, Peter S. Zehr
Graduate Theses, Dissertations, and Problem Reports
A novel route to cyclopenta[b]quinoline-1-ones and -ols has been developed. Substituted cyclopenta[b]quinolin-1-ones were prepared by thermal ring-expansion of substituted N-BOC protected 4-(2-aminophenylethynyl)-4-hydroxy-2-cyclobuten-1-ones forming the corresponding 2-aminophenylmethylidene substituted 4-cyclopentene-1,3-diones. Deprotection of the amine resulted in spontaneous condensation to give cyclopenta[b]quinolin-1-ones. Sodium borohydride reduction of these products produced cyclopenta[b]quinolin-1-ols. The key step in the sequence is a thermally induced ring-expansion of 4-(2-aminophenylethynyl)-4-hydroxy-2-cyclobuten-1-ones. Changing the amino protecting group had no effect on the ring size selectivity of the thermal ring expansion. The thermal ring expansion of the corresponding nitro derivative suggests that electron withdrawing substituents may alter the selectivity of the ring formation. …
Supporting Awareness In Heterogeneous Collaboration Environments, Vijayanand Bharadwaj
Supporting Awareness In Heterogeneous Collaboration Environments, Vijayanand Bharadwaj
Graduate Theses, Dissertations, and Problem Reports
Rapid technological advancements have made it possible for humans to collaborate as never before. However demands of group work necessitate distributed collaboration in very heterogeneous environments. Heterogeneity as in various applications, platforms, hardware and communication infrastructure. User mobility, lack of availability and cost often make imposing a common collaboration environment infeasible. Awareness is essential for successful collaboration. Awareness is a key design criterion in groupware but often collaboration occurs with applications not designed to support useful awareness. This dissertation deals with the issue of effective group awareness support in heterogeneous environments.;Awareness propagation is effective if the appropriate amount of information, …
Three Essays On International Trade And Factor Flows, Ryo Takashima
Three Essays On International Trade And Factor Flows, Ryo Takashima
Graduate Theses, Dissertations, and Problem Reports
The dissertation aims to help us understand the economic mechanism of and the impacts of international trade and factor flows. It comprises three essays, each of which focuses a separate aspect of trade and factor flows.;First essay illuminates the issue of trade policy and illegal immigration in a rigorous theoretical analysis. We emphasize the presence of interrelationship between trade policy and illegal immigration by employing so called the Mead model. First, we present how trade policy influences the amount of illegal immigration. Second, we analyze the economic welfare of complete free trade by incorporating illegal immigration. Third, we illustrate the …
The Influence Of Beaver Impoundments On Vegetative Composition, And Modeling Habitat Suitability As A Tool For Wildlife Management And Conservation, Jerry Leanne Bonner
The Influence Of Beaver Impoundments On Vegetative Composition, And Modeling Habitat Suitability As A Tool For Wildlife Management And Conservation, Jerry Leanne Bonner
Graduate Theses, Dissertations, and Problem Reports
Beavers (Castor canadensis) can have dramatic effects on vegetative communities through impounding streams and wetlands. These alterations may influence rare plant species where beaver create ponds. We found that the youngest and oldest beaver ponds in Canaan Valley, West Virginia, USA had similar species richness. Rare plant species occurred most in oldest ponds, although no significant differences were detected. Species composition around ponds was found to be different between areas influenced by ponds versus those not affected, creating more obligate wetland communities when influenced by beaver. This information should be incorporated into management decisions when rare plant species conservation is …
Three Essays On Migration: Its Interaction With Regional Wage Differentials And Occupational Choice And Its Application In Different Discrete Choice Models, Christiadi
Graduate Theses, Dissertations, and Problem Reports
This dissertation consists of three essays that examine two important roles of migration, promoting regional wage convergence and increasing economic efficiency. The first essay is a survey of the migration and migration-related literatures, examining why migration and regional wage differentials can co-exist over time. The direct reason is that the classical assumptions leading to regional wage convergence are rarely fully applicable in the real world. This essay reveals various real-world conditions violating those assumptions and explains how they can either create or magnify regional wage differentials. The essay also reveals how the difficulty in distinguishing wage differentials from true wage …
The Stability Of The Iodate -Arsenous Acid Reaction Front While Advected By Poiseuille Flow, Robert S. Spangler
The Stability Of The Iodate -Arsenous Acid Reaction Front While Advected By Poiseuille Flow, Robert S. Spangler
Graduate Theses, Dissertations, and Problem Reports
The competition between stabilizing and destabilizing effects is a motif that occurs in every aspect of the human experience. The coupling between the dynamics of chemical reactions and fluids offers a fruitful context in which to examine the patterns that arise in the presence of this competition.;The upward-propagating iodate-arsenous acid front is an example of a system in constant struggle. As it moves upward, it leaves a reacted solution of lesser density behind (and below) it. The system is thus subjected to a Raleigh-Taylor-like instability. On the other hand, the well understood (experimentally and theoretically) relationship between the front speed …
Handcuffed Hegemony: International Restraint In Unbalanced Systems, Mark E. Schaefer
Handcuffed Hegemony: International Restraint In Unbalanced Systems, Mark E. Schaefer
Graduate Theses, Dissertations, and Problem Reports
This work contends that the current systemic view of hegemonic systems is incorrect. On one hand hegemonic actors are conceptualized as omnipotent actors that can mold the system to best reflect its goals. Still, others illustrate that such unipolar systems can never be achieved, or at best exist for a short time as other powers move to rebalance the international system. Mearsheimer illustrates a more realistic approach, that unbalanced multipolar systems can exist, in which a larger state is present in a traditional multipolar system, not a traditional vertical authority structure. He contends that such a system is transient, for …
An Ecological Study Of Panax Quinquefolius In Central Appalachia: Seedling Growth, Harvest Impacts And Geographic Variation In Demography, Martha E. Van Der Voort
An Ecological Study Of Panax Quinquefolius In Central Appalachia: Seedling Growth, Harvest Impacts And Geographic Variation In Demography, Martha E. Van Der Voort
Graduate Theses, Dissertations, and Problem Reports
American ginseng (Panax quinquefolius L.) is a long-lived, slow-maturing understory perennial herb found in eastern North American forests. The economic value of P. quinquefolius on the world market has remained strong for nearly 300 years. It has high economic and social value in the central Appalachians as well. Persistent harvest of ginseng combined with habitat loss has reduced populations in the wild, threatening the future of the species and its continued harvest. American ginseng was placed on the CITES Appendix II list in 1973 due to population declines. These concerns led to a series of studies investigating the population dynamics …
A Web-Based Environment For Automated Dental Identification Research, Satyasrinivas Chekuri
A Web-Based Environment For Automated Dental Identification Research, Satyasrinivas Chekuri
Graduate Theses, Dissertations, and Problem Reports
The Criminal Justice Information Services (CJIS), division of the Federal Bureau of Investigations (FBI), include in its strategic plan the creation of an Automated Dental Identification System (ADIS), a Post Mortem Dental Identification System.;This project aims at designing an end-to-end web-interface to meet the requirements of ADIS like Identification, Maintenance and Bridge Modules. In Identification Mode the subject record will be uploaded by the user and the match list is obtained as result. Maintenance Mode enables uploading of reference records and to populate the database with preprocessing data. Bridge Module enables researchers from other universities to use the database designed …
An Integrated Computer-Based Timber Cruising System For Appalachian Hardwoods, Jingxin Wang
An Integrated Computer-Based Timber Cruising System For Appalachian Hardwoods, Jingxin Wang
Graduate Theses, Dissertations, and Problem Reports
In order to facilitate resource data collection and processing, an integrated computer-based timber cruising system was modeled and developed based on Microsoft Component Object Model (COM) and Objected-Oriented Programming (OOP) techniques. The system consists of three components - handheld data collection system, data transfer, and data analysis, all of which are stand-alone objects. The handheld system, which is Windows CE based, was used to collect overstory and understory tree data in the field. Data transfer and analysis components reside on a desktop PC and were used to synchronize cruising data from handheld PCs, analyze data and generate reports. A relational …