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Harvested Log Damage And Value Loss Associated With Two Ground-Based Harvesting Systems In Central Appalachia, Michael R. Vanderberg Dec 2002

Harvested Log Damage And Value Loss Associated With Two Ground-Based Harvesting Systems In Central Appalachia, Michael R. Vanderberg

Graduate Theses, Dissertations, and Problem Reports

Damage is often seen as an important consideration when conducting partial harvests in hardwood stands, as excessive damage to residual trees will significantly reduce the potential value of the residual stand. Damage to harvested logs, especially hardwood saw and veneer logs can be an even more important concern relative to value loss associated with log degrade. The log damage and value loss were examined by harvesting system, felling function, species, and damage type in central Appalachia. Observations were made of all grade logs during the felling, skidding, decking/sorting, and loading functions of the harvesting operations. Saw logs or veneer logs …


Electron Transfer Kinetic Studies Of 1-Electron, 1-Proton Redox Couples Attached To Electrodes, Robert M. Haddox Dec 2002

Electron Transfer Kinetic Studies Of 1-Electron, 1-Proton Redox Couples Attached To Electrodes, Robert M. Haddox

Graduate Theses, Dissertations, and Problem Reports

Proton Coupled Electron Transfer (PCET) reactions play a vital rote in a variety of biological and chemical processes. Prior work by E. Laviron developed the theory of proton coupled electron transfer kinetics based on a stepwise mechanism with the transfer coefficient for electron transfer remaining constant at all overpotentials. The present work explores the consequences of a potential-dependent transfer coefficient as applied to redox couples attached to electrodes. Specifically, this work focuses on the 1-electron, 1-proton (1e1H) system. Derivation of the potential-dependence of the transfer coefficient comes from the Marcus density-of-states model of heterogeneous electron transfer. Two 1e1H systems are …


Impact Of Early Childhood Perceptions And Experiences On Oral Health Practices In Later Life, Johnna Marie Guzzi Dec 2002

Impact Of Early Childhood Perceptions And Experiences On Oral Health Practices In Later Life, Johnna Marie Guzzi

Graduate Theses, Dissertations, and Problem Reports

Older adults are at a higher risk for numerous oral and systemic diseases. Oral conditions experienced by the elderly are believed to be cumulative. The purpose of this study was to determine if a relationship exists between early childhood dental care practices/experiences and perceived oral health needs of persons 60 years of age and older who are participants of three West Virginia facilities for the elderly (N = 90). Individuals were interviewed utilizing a two-part 21-item survey. Data analyses, including analysis of variance and tests of chi square, were conducted using the JMP program. Although individuals felt dental health was …


Mode I Fracture And Durability Of The Cfrp -Concrete Interface Bond, David Moses Boyajian Dec 2002

Mode I Fracture And Durability Of The Cfrp -Concrete Interface Bond, David Moses Boyajian

Graduate Theses, Dissertations, and Problem Reports

The continual degradation of civil infrastructures worldwide has prompted the need for effective solutions, posing major challenges to those involved with reinforced concrete structures. Externally bonded fiber reinforced polymer (FRP) composites have proven to be an efficient means of rehabilitation and enhancement to both existing and new structures alike. An important issue regarding this technology that needs further exploration, however, is the strength and integrity of the interface bond---the inadequacy of which can result in premature failure of the reinforced member.;Until now, there were no available methods to rigorously evaluate the interface bond strength and integrity for concrete structures externally …


Automation Of The Superpave Mix Design Process For The West Virginia Division Of Highways, Martin Felix Padula Dec 2002

Automation Of The Superpave Mix Design Process For The West Virginia Division Of Highways, Martin Felix Padula

Graduate Theses, Dissertations, and Problem Reports

During the fifty years between 1940 and 1990, the nation's bituminous roadways were predominantly designed using either the Marshall or Hveem method. The Superior Performing Asphalt Pavements (Superpave)(TM) method was later developed to address the issues of increased traffic volumes and heavier loads on the nation's roadways. This new mix design process relies on volumetric calculations and graphs, which are cumbersome to perform by hand. There is no current public domain Superpave software package available which is independent of any commercial laboratory product and available to an asphalt mix designer. A component of this research project consisted of creating a …


Effects Of Response-Independent Stimulus Delivery And Functional Communication Training, Shannon S. Haag Dec 2002

Effects Of Response-Independent Stimulus Delivery And Functional Communication Training, Shannon S. Haag

Graduate Theses, Dissertations, and Problem Reports

Two individuals with developmental delays with a history of problem behavior participated in this study. Its purpose was to examine the efficacy of combining two treatments demonstrated to reduce problem behavior: response-independent stimulus delivery and differential reinforcement of an alternative behavior. This study examined whether the response-independent delivery of an alternative preferred stimulus and differential reinforcement of manding resulted in increases in manding and suppression of problem behavior prior to and during the fading of the schedule of response-independent stimulus delivery. The study also examined the necessity of extinction to obtain suppression of problem behavior. The response-independent delivery of an …


Mode-I Fatigue Fracture Of Interface For Fiber -Reinforced Polymer Composite Bonded To Wood, Junhui Jia Dec 2002

Mode-I Fatigue Fracture Of Interface For Fiber -Reinforced Polymer Composite Bonded To Wood, Junhui Jia

Graduate Theses, Dissertations, and Problem Reports

For applications in civil infrastructure rehabilitation and new construction, wood is being reinforced with externally bonded laminates and fabrics of fiber-reinforced polymer (FRP) composites. The potential benefits of external reinforcement with bonded FRP composites have been demonstrated through several studies, and the field implementation of this technology has been successfully proven in numerous projects. However, there is a concern with the long-term performance of the interface bond, since an inadequate bond strength and integrity can render the reinforcement ineffective and lead to premature failure of the structure. The performance of FRP-wood bonded interfaces under static and environmental loads have been …


Evaluations Of Concrete Overlays For Bridge Deck Applications, Shiwei Luo Dec 2002

Evaluations Of Concrete Overlays For Bridge Deck Applications, Shiwei Luo

Graduate Theses, Dissertations, and Problem Reports

Protective concrete deck overlays have been successfully used by WVDOH in a number of old and new concrete bridge decks to extend their service life, but in several cases delamination and failures have been observed. A comprehensive study has been recently defined to investigate overlays performance and delamination, culminating eventually in the development of specifications in collaboration with WVDOH and the Contractors and Building Supplies Associations of WV.;The present study is an exploratory research concerned with evaluations of four types of overlays for bridge deck applications, and include: latex modified concrete (LMC), microsilica modified concrete (MMC), microsilica modified concrete with …


Students' Perceptions Of Nonnative Esl Teachers, Etelvo Ramos Filho Dec 2002

Students' Perceptions Of Nonnative Esl Teachers, Etelvo Ramos Filho

Graduate Theses, Dissertations, and Problem Reports

There has been a lot of research on native speaker and nonnative speaker teachers of English as a second language. Authors have addressed negative and positive aspects of these two classes. However, there has not been much research on how students of English as a second language see their nonnative instructors. This qualitative study addresses this issue. In this study I investigated how learners perceive their nonnative speaker teachers. The data were collected through a questionnaire, class observations, and audio-taped interviews with the 16 participants. Two nonnative instructors, who taught the participants, were interviewed also. Overall, despite some negative perceptions, …


Zinc Pot Bearing Material Wear Rate As A Function Of Contact Pressure And Velocity, James M. Snider Ii Dec 2002

Zinc Pot Bearing Material Wear Rate As A Function Of Contact Pressure And Velocity, James M. Snider Ii

Graduate Theses, Dissertations, and Problem Reports

There are currently over 50 galvanizing lines in operation in the United States producing approximately 50 million tons per year of galvanized sheet. Frequently zinc-pot hardware fails which causes production delay, resulting in an economic loss. It takes approximately 3 hours to change the zinc-pot bearings at a downtime cost of {dollar}400/h.;To predict the performance of the submerged bearings, a large number of variables must be considered. These variables include pot chemistry, temperature, line speed and line tension. With these variables it is possible to develop a design guide for sheet mill operators to determine the most cost-effective selection of …


Chemical And Physical Properties Of Acid Mine Drainage Floc, Catherine M. Bohan Dec 2002

Chemical And Physical Properties Of Acid Mine Drainage Floc, Catherine M. Bohan

Graduate Theses, Dissertations, and Problem Reports

Acid mine drainage is a serious environmental concern in many regions worldwide, but especially in coal and metal mining regions. These acid drainages are often treated with chemicals to raise the pH of the water and to cause neutralization and precipitation of metals. As neutralization occurs, a looser gelatinous material called "floc" is produced. The effects of neutralizing chemical, pH, sulfate to iron molar ratio, and solids concentration on floc settling properties were determined in synthetic acid mine drainage. Sulfate was the important factor affecting floc physicochemical properties, increasing settling times from 25-125% and decreasing settling rates from 24-63%. Neutralization …


Immunomodulatory Roles Of Endotoxin And Glutaraldehyde In The Development Of Latex Allergy, Michael D. Howell Dec 2002

Immunomodulatory Roles Of Endotoxin And Glutaraldehyde In The Development Of Latex Allergy, Michael D. Howell

Graduate Theses, Dissertations, and Problem Reports

Although much data has been obtained related to the clinical manifestations of latex allergy and the characterization of the protein allergens, little is known regarding the natural history of the disease. These studies were undertaken to demonstrate the immunological relevance of both dermal and respiratory exposure in the development of latex allergy and to investigate the role of co-exposure by these routes to other agents in the health care environment on the development of NRL sensitization.;An initial study in female BALB/c mice demonstrated comparable rates of induction of latex specific IgE following dermal and respiratory latex exposure, demonstrating the importance …


Three Essays On Data Contaminants, Outliers And Macroeconomic Time Series, Joseph Michael Palardy Dec 2002

Three Essays On Data Contaminants, Outliers And Macroeconomic Time Series, Joseph Michael Palardy

Graduate Theses, Dissertations, and Problem Reports

This thesis illustrates the effects of outliers on forecasting and on simulated general equilibrium models. The first essay demonstrates that using robust-estimation techniques may greatly improve long-run autoregressive forecasts if the model to be estimated is generated from a heavy-tailed distribution. The second essay continues with a similar theme. It shows that in the context of random contamination models, automatic autoregressive selection criteria may be severely inaccurate. If the estimated model is misspecified, forecasting accuracy may be considerably reduced. Once again, robust-estimation techniques limit the influence of the aberrant data---in this case from the contaminating distribution. The third essay demonstrates …


Impulsivity And Friends Who Smoke As Predictors Of Adolescent Smoking, Brady Reynolds Dec 2002

Impulsivity And Friends Who Smoke As Predictors Of Adolescent Smoking, Brady Reynolds

Graduate Theses, Dissertations, and Problem Reports

The present study sought to examine relations between different stages of adolescent cigarette smoking and the variables of impulsivity (delay and probability discounting) and peer friend smoking behavior. Participants were 75 adolescents (40 females) between 14 and 16 years of age. Participants were categorized according to the following patterns of smoking behavior: "never smokers" (n = 19; 10 females) were those who had not tried even one cigarette; "triers" (n = 17; 9 females) were those who had recently tried cigarettes (M = 3.76 cigarettes) for the first time; "past experimenters" (n = 20; 12 females) were those who had …


Essays In International Asset Pricing, Hong Wu Dec 2002

Essays In International Asset Pricing, Hong Wu

Graduate Theses, Dissertations, and Problem Reports

This dissertation attempts to assess the ability of various international asset pricing models in explaining asset returns across countries. The Introduction discusses the links between the chapters, the contributions I make and states what I have learned from the dissertation. Chapter 1 of the dissertation derives (in a discrete time framework to facilitate the transition from theory to empirical analysis) a consumption based capital asset pricing model with the added feature of a "keeping up with the Joneses" utility function and applies it in an international context to explain return differences across countries. Relying on the Lucas (1978) asset pricing …


Calculation Of Thermal Expansion Of Iron -Aluminides With Transition Metal Additives, Tatiana Seletskaia Dec 2002

Calculation Of Thermal Expansion Of Iron -Aluminides With Transition Metal Additives, Tatiana Seletskaia

Graduate Theses, Dissertations, and Problem Reports

The addition of transition metal elements can significantly modify physical properties of intermetalic compounds. We studied the influence of Mo and V additives on thermal expansion coefficient (CTE) of Fe3Al and FeAl over the wide range of temperatures. The site preference of both transition metals was determined by FP-LMTO method. Fe3Al in DO3 structure has three non-equivalent lattice sites: FeI site surrounded by eight iron atoms, FeII site with four iron and four aluminum nearest neighbors and Al site. Our calculations show that Fe, site is energetically more favorable for both Mo and V. The obtained site-selection energies of Mo …


Expression And Regulation Of C-Myb In B-Lymphocyte Development, Candice Lashawn Damiani Dec 2002

Expression And Regulation Of C-Myb In B-Lymphocyte Development, Candice Lashawn Damiani

Graduate Theses, Dissertations, and Problem Reports

B lymphocytes are continually produced in bone marrow from pluripotential hematopoietic stem cells. Lymphopoiesis is characterized by a series of highly regulated genotypic and phenotypic changes resulting in immunocompetent effector cells which express cell surface immunoglobulin. Our laboratory has focused on defining extracellular signals regulating lymphoid progenitor cell survival, proliferation, and differentiation. These studies have demonstrated that pro-B cell survival, proliferation, and differentiation are regulated by interactions with fibroblastic stromal cells in the hematopoietic microenvironment. However, specific molecular mechanisms by which stromal cells regulate B lymphoid development are largely unknown. In an attempt to better understand molecular mechanisms regulating maturation …


Characterization Of Infield Duty Cycles And Exhaust Emissions From Diesel Powered Off-Road Heavy-Duty Equipment, Jeremiah Christopher Rohrbaugh Dec 2002

Characterization Of Infield Duty Cycles And Exhaust Emissions From Diesel Powered Off-Road Heavy-Duty Equipment, Jeremiah Christopher Rohrbaugh

Graduate Theses, Dissertations, and Problem Reports

The objective of study was to design, develop, and evaluate techniques to measure exhaust emissions from diesel-powered off road equipment. Emissions data was collected from a Komatsu hydraulic excavator and a Caterpillar track-type tractor.;For the excavator, data was logged during in-field operation, and test cycles were created on a dynamometer test bed using this data. For the tractor, on-board emissions measurement equipment collected mass emissions rate data in field.;Vast differences were found between transient and 8-mode brake-specific test results. Transient cycle HC, CO, CO2, NO, and PM emissions were 50%, 65%, 10%, 35%, and 50% lower than 8-Mode results, respectively. …


Application Evaluation Of A Prototype Backscatter Imaging Ldv System (Bils), Preetanshu Pandey Dec 2002

Application Evaluation Of A Prototype Backscatter Imaging Ldv System (Bils), Preetanshu Pandey

Graduate Theses, Dissertations, and Problem Reports

This study focuses on the application evaluation of a prototype backscatter imaging LDV system (BILS). This non-intrusive instrument has the ability to record particle images and two-dimensional velocity data simultaneously. A series of validation tests were conducted to verify the operation of the system. These included comparing the velocity of a wire, attached to a rotating disc, with known angular frequency (measured by digistrobe), with that measured by the instrument. The results were found to be in good agreement. The imaging part of BILS was calibrated using a target with known dimensions.;The terminal velocities and particle sizes of near-spherical, Nu-pareil …


Quantifying The Impact Of The Wto On Kuwait, Reyadh Y. Faras Dec 2002

Quantifying The Impact Of The Wto On Kuwait, Reyadh Y. Faras

Graduate Theses, Dissertations, and Problem Reports

The major contribution of this study is to quantify the economic impact of Kuwait's membership in the World Trade Organization (WTO) on supply, demand, welfare and terms of trade. A general equilibrium international trade model is used to obtain quantitative results. The model is theoretically static and based on the assumptions of perfect competition and constant returns to scale. However, it was estimated and simulated dynamically.;After specifying the model theoretically it is estimated empirically by linearizing the supply and demand equations that were obtained from solving the model analytically. The estimated model is used in a number of simulation exercises …


Dendritic Development Of Gabaergic Cortical Interneurons Revealed By Biolistic Transfection With Gfp, Xiaoming Jin Dec 2002

Dendritic Development Of Gabaergic Cortical Interneurons Revealed By Biolistic Transfection With Gfp, Xiaoming Jin

Graduate Theses, Dissertations, and Problem Reports

Neurons using gamma-aminobutyric acid (GABA) as a neurotransmitter are critically important as inhibitory neurons in the CNS. A major hindrance to further studies of this important and highly diverse class of neurons is their relative scarcity, which makes it difficult to identify and target them for morphological and physiological studies. To overcome this difficulty, we developed a novel protocol for visualizing detailed morphology of GABAergic neurons in living mouse brain slice cultures, using biolistic transfection with GAD67-GFP. The morphological, immunocytochemical and physiological characteristics of GAD67-GFP expressing neurons indicated that they were functional GABAergic neurons. Additionally, our data demonstrate that this …


Numerical Modeling Of Air Blast Effects On Hybrid Structures, Matthew J. Fox Dec 2002

Numerical Modeling Of Air Blast Effects On Hybrid Structures, Matthew J. Fox

Graduate Theses, Dissertations, and Problem Reports

Blast resistant structures are gaining increased need in today's society. This research addresses adding composite reinforcement to existing concrete structures to decrease blast damage. An upgraded material model for concrete is presented. This model, used in LS-DYNA3D, incorporates tensile damage, which allows the concrete to degrade as it is loaded. The concrete model is tested using existing unreinforced and reinforced concrete beam tests. Some beams were plain, others were externally reinforced with composites, bonded to the exterior of the beams. There is a very good correlation between the predicted and existing data. The concrete model was then used to predict …


Formation And Dissociation Reaction Rates And Relevant Kinetic Behavior Of Propane Gas Hydrate (Pgh), Feng Song Dec 2002

Formation And Dissociation Reaction Rates And Relevant Kinetic Behavior Of Propane Gas Hydrate (Pgh), Feng Song

Graduate Theses, Dissertations, and Problem Reports

The formation and dissociation reaction rates and their kinetic behavior of propane gas hydrate (PGH) within the well-defined sediment particle's packing structures were experimentally investigated in this work by using a multi-phase heterogeneous reaction system, consisting of propane gas (g), water (l), PGH (s) and sediment particles (glass beads) (s). This work was carried out under the formation conditions of P = 0.427 MPa and T = 273.5 K, and under the dissociation conditions of P ≤ 0.168 MPa and T = 273.5 K.;A new designed, isothermal, and packed bed batch reactor was used for the kinetic analysis of the …


Mechanical Characterization Of Aged Recycled Polymers And Applications, Jose Ricardo Basto Dec 2002

Mechanical Characterization Of Aged Recycled Polymers And Applications, Jose Ricardo Basto

Graduate Theses, Dissertations, and Problem Reports

The research focuses on the evaluation of mechanical properties (tension, bending, compression, impact, hardness and creep) of recycled acrylonitrile butadiene styrene (ABS) and polycarbonate (PC) thermoplastics obtained as electronic shredder residue (ESR) from computer housings. Three forms of polymers, i.e., virgin, blend of virgin and recycled, and 100% recycled were investigated to establish their long term mechanical properties. Chopped and continuous glass fiber/fabric addition to the resins was evaluated to study the thermo-mechanical properties.;Mechanical characterization was carried out at freeze-thaw cycling aging. It was found that recycled polymers retain at least 70% of their tensile, bending and compressive strength after …


Early Component-Based Reliability Assessment Using Uml Based Software Models, William Black Smith V Dec 2002

Early Component-Based Reliability Assessment Using Uml Based Software Models, William Black Smith V

Graduate Theses, Dissertations, and Problem Reports

In the last decade, software has grown in complexity and size, while development timelines have diminished. As a result, component-based software engineering is becoming routine. Component-based software reliability assessment combines the architecture of the system with the reliability of the components to obtain the system reliability. This allows developers to produce a reliable system and testers to focus on the vulnerable areas.;This thesis discusses a tool developed to implement the methodology previously created for early reliability assessment of component-based systems. The tool, Early Component-based Reliability Assessment (ECRA), uses Rational Rose Unified Modeling Language (UML) diagrams to predict the reliability of …


Relationships Among Spirituality, Cognitive Processing, And Personal Control, Karri Bonner Dec 2002

Relationships Among Spirituality, Cognitive Processing, And Personal Control, Karri Bonner

Graduate Theses, Dissertations, and Problem Reports

The current study was a cross-sectional investigation of how spirituality as a positive life theme might be related to a unique style of cognitive processing. Of secondary interest were the relationships among spirituality and other personal control variables. Using memory recall and recognition tasks, the current study sought to determine whether or not participants would attend more to positive, negative, neutral, or religious words. The results of the current study indicate that (1) older adults are more spiritual than younger adults, (2) higher spirituality is related to higher levels of optimism, (3) spirituality is related to an external locus of …


Rubber Toughening Of Glass-Fiber -Reinforced Nylon 66, Fares D. Alsewailem Dec 2002

Rubber Toughening Of Glass-Fiber -Reinforced Nylon 66, Fares D. Alsewailem

Graduate Theses, Dissertations, and Problem Reports

Glass fibers are commonly added to thermoplastics by the process of extrusion compounding for a variety of reasons, mainly to enhance their strength and make them dimensionally stable. Since the extruder has to be flushed out each time product composition is changed, a large amount of incompatible polymeric waste is generated. This waste material is usually landfilled even though the polymers contained in it are valuable and worth being recycled. It is the drastic reduction in mechanical properties resulting from polymer incompatibility which restricts their recycling. A good strategy of recycling thermoplastics calls for separating materials from each other before …


Propensity Of West Virginia Craftspeople To Use Electronic Media For Marketing Their Products, Karen Kay Norwood Dec 2002

Propensity Of West Virginia Craftspeople To Use Electronic Media For Marketing Their Products, Karen Kay Norwood

Graduate Theses, Dissertations, and Problem Reports

The purpose of this study was to determine whether craftspeople in West Virginia were ready to use new communication technologies to market their products, by cooperative or other business structures. Survey respondents completed their self-reports and mailed questionnaires back to the researcher for both quantitative tabulation and documentation of additional comments.;The survey instrument focused on four areas of inquiry regarding craftspeople: (1) knowledge and skills of using electronic media for marketing; (2) experience, potential and interest in using communication technologies in cooperative or other group marketing efforts; (3) perceptions about the electronic communication infrastructure; and (4) perceptions of their degree …


Effects Of Nitrogen Fertilizer And Red Clover (Trifolium Pratense L.) Component On Productivity Of Grass-Legume Mixed Swards, Chamil Salinda Kandapola Dec 2002

Effects Of Nitrogen Fertilizer And Red Clover (Trifolium Pratense L.) Component On Productivity Of Grass-Legume Mixed Swards, Chamil Salinda Kandapola

Graduate Theses, Dissertations, and Problem Reports

The effects of two levels of red clover (low and high) and three levels of N fertilizer (0, 28, 56 N kg ha-1) on herbage accumulation and quality of grass-legume mixed swards were studied. Total herbage accumulation of the mixtures with high legume percentage was significantly higher than those with low legume percentage and this was most pronounced at second harvest. Swards high in legumes also had higher crude protein concentrations and lower weed percentages than those low in legumes. Although the effect of N on herbage accumulation was not significant, an increase was observed for crude protein concentration of …


Sport Fish Consumption Advisory For West Virginia, William Alvin Warnick Dec 2002

Sport Fish Consumption Advisory For West Virginia, William Alvin Warnick

Graduate Theses, Dissertations, and Problem Reports

The risk based sport fish consumption advisory protocol, West Virginia Sport Fish Consumption Advisory Guide (the Guide), was drafted for the state. Fish were collected from ten West Virginia sites (5 previously identified as contaminated, 5 previously identified as uncontaminated). Fish samples were collected, processed and analyzed for total mercury concentration and Aroclors (PCBs). Recommended meal frequencies were calculated from contaminant levels and based on the Guide. Mean fillet sample contaminant levels were compared to composite sample levels and found to require the same level or in one case a more protective of consumption advisory. Ten composite samples had Aroclor …