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Architectural Level Risk Assessment, Ahmed E. Hassan
Architectural Level Risk Assessment, Ahmed E. Hassan
Graduate Theses, Dissertations, and Problem Reports (ETD)
Many companies develop and maintain large-scale software systems for public and financial institutions. Should a failure occur in one of these systems, the impact would be enormous. It is therefore essential, in maintaining a system's quality, to identify any defects early on in the development process in order to prevent the occurrence of failures. However, testing all modules of these systems to identify defects can be very expensive. There is therefore a need for methodologies and tools that support software engineers in identifying the defected and complex software components early on in the development process.;Risk assessment is an essential process …
Three Essays On The Profitability, Risk, And Viability Of Family Firms In A Developing Economy, Kamol Khaemasunun
Three Essays On The Profitability, Risk, And Viability Of Family Firms In A Developing Economy, Kamol Khaemasunun
Graduate Theses, Dissertations, and Problem Reports (ETD)
The objective of this dissertation is to examine the family firms in term of profit, risk and the probability of their survival in developing countries. The first chapter gives an introduction to this study. The second chapter provides an analysis of family businesses in regard to their performance, since there have been claims in the popular press that family-centered "crony capitalism" significantly contributed to the Asian financial crisis of 1997. Small, tightly focused firms can, however, be well managed by family hierarchies. As firms grow and diversify, family management is often displaced by diffuse ownership and independent managers. Between these …
Synchronization For Capacity -Approaching Coded Communication Systems, Jian Sun
Synchronization For Capacity -Approaching Coded Communication Systems, Jian Sun
Graduate Theses, Dissertations, and Problem Reports (ETD)
The dissertation concentrates on synchronization of capacity approaching error-correction codes that are deployed in noisy channels with very low signal-to-noise ratio (SNR). The major topics are symbol timing synchronization and frame synchronization.;Capacity-approaching error-correction codes, like turbo codes and low-density parity-check (LDPC) codes, are capable of reaching very low bit error rates and frame error rates in noisy channels by iterative decoding. To fully achieve the potential decoding capability of Turbo codes and LDPC codes, proper symbol timing synchronization, frame synchronization and channel state estimation are required. The dissertation proposes a joint estimator of symbol time delay and channel SNR for …
Development Of A Program To Gather And Process Data From Oil And Gas Fields, Joshua R. Cook
Development Of A Program To Gather And Process Data From Oil And Gas Fields, Joshua R. Cook
Graduate Theses, Dissertations, and Problem Reports (ETD)
In this thesis new software is developed to examine the needs and available options to gather information from oil and gas fields and to analyze data in an efficient manner. The program outlines potential setups as well as practical analysis techniques. The result is a program to store field data and capability to analyze input in different formats.;The developed system uses accounting, economics, engineering, and management concepts to process data. The program uses the relationships between field data gathered in a number of methods. The developed program provides a useful tool for the engineer to gather oil and gas field …
Factors Influencing Basal Area Growth Of Yellow-Poplar ( Liriodendron Tulipifera L.) In Central West Virginia, Christopher T. Crum
Factors Influencing Basal Area Growth Of Yellow-Poplar ( Liriodendron Tulipifera L.) In Central West Virginia, Christopher T. Crum
Graduate Theses, Dissertations, and Problem Reports (ETD)
This paper uses data from continuous forest inventory (CFI) plots to evaluate basal area growth of yellow-poplar (Liriodendron tulipifera L.) as related to four topographic factors (aspect, slope position, steepness, and landform), two competition variables (basal area per acre and trees per acre) and four tree characteristics (age, diameter, total height, and crown diameter). These variables were plotted against basal area growth per year using simple linear regression on 69 yellow-poplar trees. The four tree characteristics all had a highly significant (p < .01) relationship with basal area growth. While the other variables did not exhibit a significant relationship, the two competition variables did have a significant (p < .05) relationship with each other.
Comparison Of Chestnut Canker Treatment Procedures For Hypovirus Introduction, Brian C. Bell
Comparison Of Chestnut Canker Treatment Procedures For Hypovirus Introduction, Brian C. Bell
Graduate Theses, Dissertations, and Problem Reports (ETD)
Historically, hypovirulent strains of Cryphonectria parasitica have been introduced into cankers principally by inoculating wounds made to the margin of cankers. Twelve hypovirus introduction methods were tested. Seventy-two trees were inoculated in June 2002 with an orange-pigmented virulent strain of C. parasitica (two inoculations per tree). After 11 weeks, the resulting cankers were treated with a brown-pigmented hypovirulent C. parasitica isolate using one of the following methods: (1) a non-invasive treatment where the inoculum was painted onto the canker surface; (2) an invasive treatment where the canker face was wounded with a sharp blade prior to the painting application of …
Experimental Validation Of The "Target Hood Static Pressure" Balancing Method For Exhaust Ventilation Systems, Michael Winifred Dodrill
Experimental Validation Of The "Target Hood Static Pressure" Balancing Method For Exhaust Ventilation Systems, Michael Winifred Dodrill
Graduate Theses, Dissertations, and Problem Reports (ETD)
An experimental trial of a new method to balance industrial exhaust ventilation systems was performed. Although balance by design is considered preferable, many ventilation systems incorporate dampers to balance the system to a different airflow distribution after installation. The "target hood static pressure" method aims to minimize the time, effort, frustration and confusion invested in the balancing effort. It requires only one and one-half adjustment rounds, can be prepared as a computerized spreadsheet, and substitutes hood static pressure readings for airflow traverse readings. The method also minimizes the system static pressure to the least possible, thereby keeping friction losses at …
Factors Underlying Stalking And Harassing Behavior In A College Population, Jill Johansson-Love
Factors Underlying Stalking And Harassing Behavior In A College Population, Jill Johansson-Love
Graduate Theses, Dissertations, and Problem Reports (ETD)
At the high end of unwanted pursuit behavior is stalking. This study, using questionnaires, investigated a sample of 48, college females, identified as potential stalkers. Factors examined included: demographic information, social desirability, psychological functioning, attachment, motive, rape myth acceptance, adversarial sexual beliefs, criminal thinking styles, and the actual unwanted pursuit behavior. Hypotheses regarding the criminal thinking styles of the individuals engaging in harassing and stalking behavior were supported at the .05 level. These findings indicate that harassers and stalkers exhibit criminal thinking patterns, such as sacrificing internal control to exert control over the external environment and justifying behavior by externalizing …
Resonant Optical Waveguide Biosensor Characterization, Shantanu Pathak
Resonant Optical Waveguide Biosensor Characterization, Shantanu Pathak
Graduate Theses, Dissertations, and Problem Reports (ETD)
The importance of miniaturized sensors for quick and accurate assessments of a broad spectrum of hazardous biological agents has been highlighted by recent high profile events. Integrated optical devices based on evanescent wave interrogation techniques can register minute refractive index changes enabling detection of bioagents on the sensor surface and providing a potential for compact structure combined with a possibility of detecting several analytes simultaneously by fabricating multiple devices on the same chip. Most commonly integrated optical interrogation techniques suffer from issues of optical alignment and fabrication complexities. In addition the materials used to fabricate integrated optical devices experience drifts …
Multispectral Segmentation Of Whole-Brain Mri, Nitya Krishnan
Multispectral Segmentation Of Whole-Brain Mri, Nitya Krishnan
Graduate Theses, Dissertations, and Problem Reports (ETD)
Magnetic Resonance Imaging (MRI) is a widely used medical technology for diagnosis and detection of various tissue abnormalities, tumor detection, and in evaluation of either residual or recurrent tumors. This thesis work exploits MRI information acquired on brain tumor structure and physiological properties and uses a novel image segmentation technique to better delineate tissue differences.;MR image segmentation will be important in distinguishing between boundaries of different tissues in the brain. A segmentation software tool was developed that combines the different types of clinical MR images and presents them as a single colored image. This technique is based on the fuzzy …
Empirical Assessment Of Architecture-Based Reliability Of Open-Source Software, Ranganath Perugupalli
Empirical Assessment Of Architecture-Based Reliability Of Open-Source Software, Ranganath Perugupalli
Graduate Theses, Dissertations, and Problem Reports (ETD)
A number of analytical models have been proposed earlier for quantifying software reliability. Some of these models estimate the failure behavior of the software using black-box testing, which treats the software as a monolithic whole. With the evolution of component based software development, the necessity to use white-box testing increased. A few architecture-based reliability models, which use white-box approach, were proposed earlier and they have been validated using several small case studies and proved to be correct. However, there is a dearth of large-scale empirical data used for reliability analysis. This thesis enriches the empirical knowledge in software reliability engineering. …
Trace Detection Of Mercury Using Boron-Doped Diamond Electrodes, Latha Ramakrishnan
Trace Detection Of Mercury Using Boron-Doped Diamond Electrodes, Latha Ramakrishnan
Graduate Theses, Dissertations, and Problem Reports (ETD)
This Project was undertaken to develop electrochemical techniques using Boron-doped Diamond (BDD) electrodes for the purpose of detecting mercury in solutions in the ppb-ppt range. Differential Pulse Voltammetry (DPV) was used successfully to develop calibration curves for mercury detection in standard solutions in the ppb-ppt range, followed by using these curves for mercury measurements in unknown samples. DPV experiments were performed in nitrate, thiocyanate and chloride media. Investigation in the chloride medium is important since practical samples always contain chloride impurities. The formation of calomel in chloride medium is avoided on the BDD surface by the co-deposition of 3ppm of …
Forensic Analysis Of Digital Evidence From Palm Personal Digital Assistants, Christopher M. Mcnemar
Forensic Analysis Of Digital Evidence From Palm Personal Digital Assistants, Christopher M. Mcnemar
Graduate Theses, Dissertations, and Problem Reports (ETD)
Personal Digital Assistants are becoming more affordable and commonplace. They provide mobile data storage, computational, and network abilities. When handheld devices are involved in a crime, forensic examiners need tools to properly retrieve and analyze data present on the device. Unfortunately, forensic analysis of handheld devices is not adequately documented and supported.;This report gives an overview of Palm handheld development and current forensic software related to Personal Digital Assistants. Procedures for device seizure, storage, imaging, and analysis are documented. In addition, a tool was developed as part of this work to aid forensic examiners in recovering evidence from memory image …
Real-Time Video Compression Using Dvq And Suffix Trees, Pavan Kumar Vedantam
Real-Time Video Compression Using Dvq And Suffix Trees, Pavan Kumar Vedantam
Graduate Theses, Dissertations, and Problem Reports (ETD)
Video processing is a wide and varied subject area. Video compression is an important but difficult problem in video processing. Several methods and standards exist which address this problem with varying degrees of success depending on the performance measures adopted. The present research work focuses on the real-time aspect of video processing.;In particular we propose a real-time video compression algorithm based on the concept of differential vector quantization and the suffix tree. Differential vector quantization is a relatively new area that focuses on efficient compression of data. The present work integrates the compression provided by Differential vector Quantization and the …
Models Of High-Temperature Desulfurization Using Zinc-Based Sorbents, Yong Zhang
Models Of High-Temperature Desulfurization Using Zinc-Based Sorbents, Yong Zhang
Graduate Theses, Dissertations, and Problem Reports (ETD)
This study focuses on determining models that are currently available to describe gas-solid reactions to predict the observed (experimental) results from a series of TGA experiments. Variations of the GPM (Grainy Pellet Model) were used and shown to give good agreement with experimental conversion histories of zinc oxide particle undergoing sulfidation using H2S at temperature in the range of 482 to 593 degree centigrade.;By using SEM (Scanning Electron Microscope) and Visilog(TM) imaging analysis software, the grain size distribution and grain sphericity can be obtained.;The basic forms of the SCM (Shrinking Core Model) and GPM models could not predict correctly the …
Sensitivity To Molar Contingencies Of Food Presentation, Jeffrey Everly
Sensitivity To Molar Contingencies Of Food Presentation, Jeffrey Everly
Graduate Theses, Dissertations, and Problem Reports (ETD)
Twelve rats were exposed to two variable-time schedules that differed in their rates of food delivery. The "imposed" schedule was normally in effect, but lever pressing occasionally switched to the "alternate" schedule for periods averaging 30 s. Increases in food frequency afforded by switching to the alternate schedule were manipulated across conditions. All rats were exposed to the same absolute food frequency increases, but the programming of these increases was varied among the rats by holding particular food delivery rates constant across conditions. For half of the rats, the schedules were signaled. In general, response rates were directly related to …
Use Of Commercial Cfd Software For Assessing The Performance Of Personal Aerosol Samplers, Aaron J. Bird
Use Of Commercial Cfd Software For Assessing The Performance Of Personal Aerosol Samplers, Aaron J. Bird
Graduate Theses, Dissertations, and Problem Reports (ETD)
Accurate performance of personal aerosol samplers is critical for industrial hygienists' successful efforts to protect workers. Performance assessments of personal samplers are necessarily conducted in controlled environments so unknown sources of variability will not influence the results. This is done in order that samplers may be used with confidence for monitoring workplace air quality. These performance evaluations are usually conducted in wind tunnels. However, recent advances in high-performance cluster computing---together with advanced flow modeling software---have made it possible to evaluate sampler performance with computer simulations. This was done in the current research. Simulations were conducted for air and particle behavior …
Design And Flight Testing Actuator Failure Accommodation Controllers On Wvu Yf-22 Research Uavs, Yu Gu
Design And Flight Testing Actuator Failure Accommodation Controllers On Wvu Yf-22 Research Uavs, Yu Gu
Graduate Theses, Dissertations, and Problem Reports (ETD)
This dissertation describes the design, development, and flight testing of a Neural Network (NN) based Fault Tolerant Flight Control System (FTFCS) with the ability to accommodate for actuator failures. The goal of this research was to demonstrate the ability of a specific set of control laws to maintain aircraft handling qualities in the presence of failures in the actuator channels. In this study, two-failure scenarios have been investigated: aileron failure (locking of the right aileron at a trim position) and elevator failure (locking of the right elevator at a trim position). A fleet of WVU YF-22 research aircraft test-beds were …
K--12 Teachers' Technology Integration In Benedum Collaborative Professional Development Schools, Sabah Karayegen-Giraldo
K--12 Teachers' Technology Integration In Benedum Collaborative Professional Development Schools, Sabah Karayegen-Giraldo
Graduate Theses, Dissertations, and Problem Reports (ETD)
This study investigated how K--12 teachers and interns in West Virginia University's Professional Development Schools (PDS) are using technology as a tool to enhance their students' education. The study addressed the use of technology as a classroom tool for research, communication, productivity, and problem-solving as outlined by the National Technology Standards for students. Eleven research questions framed this study. Comparisons across grade levels (elementary, middle, and high schools) and subject areas (English, mathematics, science, and social studies) were included. Descriptive and inferential statistics were used as quantitative research methods. The study involved 327 teachers and 102 intern students in these …
Evaluation Of Concrete Bridge Deck Overlays, Zhenhua Sun
Evaluation Of Concrete Bridge Deck Overlays, Zhenhua Sun
Graduate Theses, Dissertations, and Problem Reports (ETD)
Overlay systems have been used by many states for the protection of bridge decks, but the premature delaminations and failures have been observed in many cases. A comprehensive study was recently defined to investigate overlay performance in collaboration with the West Virginia Department of Transportation-Division of Highways (WVDOH).;As part of a comprehensive program, the present study is concerned with the properties of several types of overlay mixtures and the interface bond strengths between them and substrate concrete. All the materials used are of interests to WVDOH. Both fresh and hardened concrete properties of seven different overlay types were characterized. Four …
Operant Conditioning In Older Adults With Alzheimer's Disease, Adam P. Spira
Operant Conditioning In Older Adults With Alzheimer's Disease, Adam P. Spira
Graduate Theses, Dissertations, and Problem Reports (ETD)
Behavioral interventions are commonly implemented to manage agitation in older adults with dementia. However, the extent to which operant conditioning can occur in this population is unclear. The present study used a button-pressing task to evaluate the sensitivity of the responding of individuals with probable Alzheimer's disease to changes in schedules of reinforcement. Results indicate that operant conditioning can occur in older adults with AD. Specifically, three participants with AD exhibited responding that was highly sensitive to a transition from a fixed interval schedule to an extinction schedule. One participant's responding was sensitive to a more subtle transition. Comparison data …
Super Resolution Of Fingerprints, Kaustubh R. Deshpande
Super Resolution Of Fingerprints, Kaustubh R. Deshpande
Graduate Theses, Dissertations, and Problem Reports (ETD)
The goal of any biometric recognition algorithm has been to target 100% recognition rate. Even a failure of 0.1% of the cases may be disastrous to the overall performance of the algorithm given the nature of the application. The performance of the recognition module is dependent directly on the quality of the images fed to this algorithm. It is no wonder thus that enhancing these images before they are fed into the recognition algorithm has gained importance in the recent years.;In this work, we develop a super-resolution method with a specific goal to improve the resolution of biometric images. This …
Influence Of A Three-Week Wildlife Education Curriculum On Knowledge And Attitudes Of South Carolina's Marlboro County High School Ninth And Tenth-Grade Biology Students, Diane M. Krishon
Graduate Theses, Dissertations, and Problem Reports (ETD)
The purpose of this study was to assess the influence of a three-week wildlife education curriculum on knowledge and attitudes of ninth and tenth-grade biology students in South Carolina. A three-week wildlife curriculum was incorporated into three high school biology classes in the same semester. The students were pre-tested and post-tested for knowledge and attitudes. The results indicate that the three-week curriculum had a positive influence on knowledge but did not influence wildlife attitudes. However, a substantial correlation occurred between the post-test attitude and knowledge scores, indicating that as students' knowledge increased, their attitudes towards wildlife and environmental education became …
Local And Regional Impairment Of Fish Assemblages In A Mined Appalachian Watershed, Jason Gregory Freund
Local And Regional Impairment Of Fish Assemblages In A Mined Appalachian Watershed, Jason Gregory Freund
Graduate Theses, Dissertations, and Problem Reports (ETD)
I used the Cheat River watershed, West Virginia, as a model system to examine the regional impacts of extensive localized stream impairment. Acid mine drainage (AMD) in the Cheat River watershed provided a unique opportunity to test the hypothesis that regional biological condition can be impacted through multiple local sources of degradation. Acid mine drainage is the result of the interaction among pyrite-rich coal, oxygen, and water. This interaction produces a solution that is generally low in pH and buffering capacity and high in heavy metals and sulfate and is toxic to aquatic life. Acid mine drainage also has the …
Predictability Of Equity Returns And Conditional Asset Pricing, Ou Hu
Predictability Of Equity Returns And Conditional Asset Pricing, Ou Hu
Graduate Theses, Dissertations, and Problem Reports (ETD)
In this dissertation, I investigate the applicability of some asset-pricing models by exploiting the predictive power of structural variables and accommodate the characteristic of predictability of stock returns in a theoretical conditional asset-pricing framework.;In the first chapter of the dissertation, I briefly review the relevant literature on the predictability of stock returns, and discuss the motivations for my research, and finally present my contributions to the existing literature while providing some discussions for future research. Chapter 2 examines the ability of the Fama-French three-factor model and the CAPM in estimating portfolios' returns. Instead of using historical average of risk premiums …
Graph Minor, Jianbing Niu
Graph Minor, Jianbing Niu
Graduate Theses, Dissertations, and Problem Reports (ETD)
In this paper, we present three results: (1) Let G be a (k + 2)-connected non-(k - 3)-apex graph where k ≥ 2. If G contains three k-cliques, say L 1, L2, L3, such that |Li ∩ Lj| ≤ k - 2 (1 ≤ i < j ≤ 3), then G contains a Kk +2 as a minor. (2) Let G be a 6-connected claw-free graph. If delta(G) ≥ 7 and G contains three disjoint 5-cliques, say Ll, L2, L3, then G contains a K7 as a minor. (3) There is a function h : N → N, such that, for every 4-connected graph G with minimum degree at least five embedded in a surface with Euler genus g and face-width at least h(g), every longest circuit of the graph G has a chord.
Three Essays On Trade And *Development, Abhra Roy
Three Essays On Trade And *Development, Abhra Roy
Graduate Theses, Dissertations, and Problem Reports (ETD)
In the first essay of this dissertation, we analyze the role of education subsidies on child labor in a situation where parents choose the quantity of children to have as well as their educational attainment. We find that lump sum education subsidies may increase (decrease) the equilibrium level of education and child labor depending on whether parents attach more weight on education (quality) or on school enrollment. Marginal education subsidies, in general, have the exact opposite effect. Some authors have found that a rise in the cost of schooling decreases child labor in some countries while increasing it in others. …
Control System Design For A C-130 Ro-Ro Sensor Deployment Platform, Robert Paul Hayes
Control System Design For A C-130 Ro-Ro Sensor Deployment Platform, Robert Paul Hayes
Graduate Theses, Dissertations, and Problem Reports (ETD)
A WVU team of engineers designed and built a palletized system that will be used to deploy surveillance sensors from a C-130 cargo airplane. There will be two pallets, one that will house the Operator Station and one that will carry a mechanical arm with a Sensor Pod, where the sensors will reside. This pallet will be placed on the C-130 rear door, which will be opened while in flight. The mechanical arm is designed to rotate the Sensor Pod underneath the door so the sensors can observe the ground.;Computer/Electrical engineers were asked to design the control circuit for the …
Electrochemical Impedance Spectroscopy Of Proton Exchange Membrane Fuel Cell Stacks, Brian J. Hetzer
Electrochemical Impedance Spectroscopy Of Proton Exchange Membrane Fuel Cell Stacks, Brian J. Hetzer
Graduate Theses, Dissertations, and Problem Reports (ETD)
Electrochemical Impedance Spectroscopy (EIS) is applied to a small, four cell Proton Exchange Membrane (PEM) fuel cell stack to examine the stack response as the load current changes. The measured stack response is compared to a simulated response generated by a stack model that has been developed using MATLAB. The results show that the model predicted well the behavior of the VI curve for currents less than 50 Amps. The model also qualitatively predicted the impedance response as a function of current and frequency. Because of apparent model incompleteness, it was not able to predict accurately the shape of the …
Finite Element Modeling Of Crack Detection In Aircraft Structures Using Electrical Current, Ramkumar Kumar Geetha
Finite Element Modeling Of Crack Detection In Aircraft Structures Using Electrical Current, Ramkumar Kumar Geetha
Graduate Theses, Dissertations, and Problem Reports (ETD)
Various non-destructive test methods have been developed for the detection of cracks in metallic structures. Electromagnetic non-destructive testing (NDT) is one of the widely used non-destructive methods used for the detection and characterization of cracks. Utilizing the principle of electromagnetic induction, this technique is used in the areas of nuclear, aerospace, power, transport, petroleum and other industries to inspect defects in metallic sheets, plates and tubes that have good electrical conductivity.;Aircraft structures and wings are made of aluminum sheets riveted together. Cracks are often found emanating from the edge of the rivet holes which are covered by the rivets and …