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Mean Value Modeling And Control Of A Diesel Engine Using Neural Networks, Yasser Yacoub May 1999

Mean Value Modeling And Control Of A Diesel Engine Using Neural Networks, Yasser Yacoub

Graduate Theses, Dissertations, and Problem Reports (ETD)

Increasingly stringent emissions legislation and demands for improved fuel economy have mandated the need for advanced control algorithms and complicated the diesel engine calibration procedure. To this end, a neural network-based mean value model of a modern turbocharged direct injection diesel engine has been developed and validated. For a pre-specified engine speed schedule and control vector trajectory, the engine model was shown to produce accurate predictions of the turbocharger manifold charging dynamics and combustion efficiency through engine brake torque predictions. The mean value model was coupled with several sub-models to predict exhaust gaseous and particulate emissions and satisfactory predictions were …

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Domains Of Organizational Effectiveness Of Gerontology Centers In Higher Education, Allison Hale Nichols May 1999

Domains Of Organizational Effectiveness Of Gerontology Centers In Higher Education, Allison Hale Nichols

Graduate Theses, Dissertations, and Problem Reports (ETD)

This is an exploratory study that focuses on organizational effectiveness of gerontology centers and institutes at American universities. The study was modeled after studies of organizational effectiveness in higher education by Kim Cameron of Brigham Young University. The study identifies six domains of effectiveness that are important to gerontology centers and the structural and functional models and characteristics of gerontology centers that may predict the domain in which it is effective. The target population of the study was dominant coalition members of 87 gerontology centers, namely, administrators and faculty members who have the most influence on policy, direction, and performance. …

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Administrators' Influence On Job Satisfaction For West Virginia Special Education Teachers, Jennifer Pitzer Sirk May 1999

Administrators' Influence On Job Satisfaction For West Virginia Special Education Teachers, Jennifer Pitzer Sirk

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study examined the relationship between the perceived administrative support levels of special education directors and principals and the perceived intrinsic, extrinsic and overall job satisfaction levels of West Virginia special education teachers. The Supervisory Behavior Description Questionnaire (Form One) was used to measure the perceived administrative support levels. The Mohrman Cooke Mohrman Job Satisfaction Scale was used to measure the perceived intrinsic, extrinsic and overall job satisfaction levels. Ancillary information was also obtained from the respondents concerning gender, Regional Education Service Agency (RESA) area of employment, grade level of employment, special education teaching assignment areas, years of experience teaching …

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Use Of Wavelet-Packet Transforms To Develop An Engineering Model For Multifractal Characterization Of Mutation Dynamics In Pathological And Nonpathological Gene Sequences, David Lee Walker May 1999

Use Of Wavelet-Packet Transforms To Develop An Engineering Model For Multifractal Characterization Of Mutation Dynamics In Pathological And Nonpathological Gene Sequences, David Lee Walker

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study uses dynamical analysis to examine in a quantitative fashion the information coding mechanism in DNA sequences. This exceeds the simple dichotomy of either modeling the mechanism by comparing DNA sequence walks as Fractal Brownian Motion (fbm) processes. The 2-D mappings of the DNA sequences for this research are from Iterated Function System (IFS) (Also known as the "Chaos Game Representation" (CGR)) mappings of the DNA sequences. This technique converts a 1-D sequence into a 2-D representation that preserves subsequence structure and provides a visual representation. The second step of this analysis involves the application of Wavelet Packet Transforms, …

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The Effects Of Varying Concentration And Duration Of Cfc-113 Exposure On End-Exhaled Breath Cfc-113 Concentration, Demetra Grace Dalamagas May 1999

The Effects Of Varying Concentration And Duration Of Cfc-113 Exposure On End-Exhaled Breath Cfc-113 Concentration, Demetra Grace Dalamagas

Graduate Theses, Dissertations, and Problem Reports (ETD)

Subjects were exposed to different concentrations of CFC-113 for variable duration while conducting 30-minute exercise regiments. End-exhaled breath samples were collected 25, 30 and 35 minutes after the exercise regiment and quantified using gas chromatography. Three comparative studies were conducted.;A short duration administration delivered at the beginning or at the end of the regiment was compared to a long duration administration delivered at the beginning or at the end of the exercise regiment. The second study compared breath samples when 500 ppm of CFC-113 was administered at the beginning or end six minutes of the regiment. The third compared continuous …

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The Evaluation Of Research For Promotion And Tenure: An Organizational Perspective, Elsa G. Nadler May 1999

The Evaluation Of Research For Promotion And Tenure: An Organizational Perspective, Elsa G. Nadler

Graduate Theses, Dissertations, and Problem Reports (ETD)

The literature on promotion and tenure in institutions of higher education includes a substantial amount of research on various aspects of faculty productivity. Yet other research concentrates on the organizational structure of higher education. In his 1986 book, Burton Clark called for research that would examine how what he called the enterprise (the local university as opposed to the statewide system) and departments within it interact in important arenas.;This dissertation takes up Clark's challenge to examine the interaction of enterprise and department in promotion and tenure in three areas: goals, structure and operations. Content analysis of faculty handbooks from 25 …

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Preservative Treatment Evaluation Of Five Appalachian Wood Species With Four Preservatives, Jeffrey John Slahor May 1999

Preservative Treatment Evaluation Of Five Appalachian Wood Species With Four Preservatives, Jeffrey John Slahor

Graduate Theses, Dissertations, and Problem Reports (ETD)

Hardwoods have been used extensively throughout the years for many uses. In the last century, wood railway tie and bridge material has been treated almost exclusively with the preservative creosote in order to improve durability. This has led to the knowledge that hardwoods treated with creosote are extremely durable. However, there have been few well documented studies of what has been termed "treatability". This work investigated and documented the treatability of five common and abundant Appalachian hardwoods vacuum/pressure treated with the four wood preservatives creosote, chromated copper arsenate (CCA), ammoniacal copper quaternary compound Type-B (ACQ-B), and a borate preservative (TmborRTM). …

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Full-Scale Operation Of A Tubular Ultrafiltration System In The Treatment Of Oily Waste, Michael Christopher Malak May 1999

Full-Scale Operation Of A Tubular Ultrafiltration System In The Treatment Of Oily Waste, Michael Christopher Malak

Graduate Theses, Dissertations, and Problem Reports (ETD)

An aluminum company in West Virginia uses an oil-water (metal working fluid) in their rolling mill process for lubrication. In the past, the company collected the oily-waste into two lined waste ponds with a combined holding capacity of 5 million gallons. Separation of the oil-water mixture occurred as emulsifiers in the metal working fluid broke down. Free oil was skimmed resulting in a pond effluent, which contained 0.2 to 1.0% oil. Pond effluent was sprayed on a treatment field and the remaining oil was degraded naturally. The daily flow to the spray fields averaged 80,000 gallons. In 1993, concerns about …

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Harmful Events In Guardrail Crashes, Vinash Vonteru May 1999

Harmful Events In Guardrail Crashes, Vinash Vonteru

Graduate Theses, Dissertations, and Problem Reports (ETD)

While guardrails are intended to reduce the severity of ran-off-road crashes, even the best designs installed in the most appropriate locations cannot eliminate all serious injuries and fatalities associated with guardrail crashes. The performance of guardrails has been examined through controlled crash tests for the past 30 years. These tests however, could not replicate real world crash conditions and provide data on injury distributions and harmful events in guardrail-related accidents.;Recognizing these limitations, reported guardrail accidents from Highway Safety Information System (HSIS) databases were examined. Data analysis was done using two-way and three-way contingency crosstabulations. Statistical significance of the study results …

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Effects Of Feed Oil Content, Transmembrane Pressure And Membrane Rotational Speed On Permeate Water Quality In High-Shear Rotary Ultrafiltration, David Albert Masciola May 1999

Effects Of Feed Oil Content, Transmembrane Pressure And Membrane Rotational Speed On Permeate Water Quality In High-Shear Rotary Ultrafiltration, David Albert Masciola

Graduate Theses, Dissertations, and Problem Reports (ETD)

A study was conducted to investigate the effects of transmembrane pressure, membrane rotational speed and feed oil content on permeate water quality in the treatment of a synthetic metal working fluid in the HSRUF system. Permeate oil grease and total organic carbon concentrations increased with transmembrane pressure and feed oil content due to the increased density or thickness of the solute concentration boundary layer. However, hydraulic turbulence created by membrane rotation minimized the thickness of the solute concentration boundary layer therefore reducing solute permeation through the membrane. The effective decoupling of feed pressurization/recirculation from hydraulic turbulence enables the HSRUF system …

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Independent Verification Of Specification Models For Large Software Systems At The Early Phases Of Development Lifecycle, Khalid Lateef May 1999

Independent Verification Of Specification Models For Large Software Systems At The Early Phases Of Development Lifecycle, Khalid Lateef

Graduate Theses, Dissertations, and Problem Reports (ETD)

One of the major challenges facing the software industry, in general and IV&V (Independent Verification and Validation) analysts in particular, is to find ways for analyzing dynamic behavior of requirement specifications of large software systems early in the development lifecycle. Such analysis can significantly improve the performance and reliability of the developed systems. This dissertation addresses the problem of developing an IV&V framework for extracting semantics of dynamic behavior from requirement specifications based on: (1) SART (Structured Analysis with Realtime) models, and (2) UML (Unified Modeling Language) models.;For SART, the framework presented here shows a direct mapping from SART specification …

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Formalization Of Storage Considerations In Software Design, Lakshminarasimha Reddy Ankireddipally May 1999

Formalization Of Storage Considerations In Software Design, Lakshminarasimha Reddy Ankireddipally

Graduate Theses, Dissertations, and Problem Reports (ETD)

One of the technical impediments for the widespread adoption of the formal methods is an inability to address storage-related concerns such as "out of memory" errors. The focus of this dissertation is on formal specification and modular reasoning of storage-related aspects of practical components and systems. In particular, this thesis tries to address the following fundamental storage-related questions for practical component-based software development (1) Is it possible to reason statically and in a modular fashion that the system would not run "out of memory"? (2) Is it possible for the reasoning system to be modular, yet sufficiently precise with respect …

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Role Expectations And Predictions Of Trends For Human Resource Development At Large Public Universities Within The Southern Regional Education Board (Sreb) Area, Drayton Ray Justus Jr. May 1999

Role Expectations And Predictions Of Trends For Human Resource Development At Large Public Universities Within The Southern Regional Education Board (Sreb) Area, Drayton Ray Justus Jr.

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study was designed to identify the role expectations, reporting hierarchy, years in role and trends in human resource development as reported by the person responsible for human resource development in large public universities within the Southern Regional Education Board (SREB) geographic area. The population for this study was all the four-year public universities in Southern Regional Education Board states which were classified by 1997 SREB-State Data Exchange definitions as SREB I (n = 26).;Each institution in the sample was mailed a copy of the Human Resource Development (HRD) Roles Survey, an instrument developed for the purpose of this research. …

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Aging And Design Of Concrete Members Reinforced With Gfrp Bars, P. V. Vijay May 1999

Aging And Design Of Concrete Members Reinforced With Gfrp Bars, P. V. Vijay

Graduate Theses, Dissertations, and Problem Reports (ETD)

Strength and stiffness properties of GFRP bars and moisture transport phenomenon into the bars was investigated in this research for various conditioning schemes with and without the application of sustained loads. Low viscosity urethane modified vinylester resin is identified as the most suitable resin, from the durability viewpoint.;Based on accelerated test results calibrated with respect to naturally aged results it is safely concluded that the service life of the FRP bars with durable resin is about 60 years as a minimum with 20% sustained stress on the bar. Concrete cover protection on the GFRP bars enhanced the service life up …

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Stress Analysis In Longwall Entry Roof Under High Horizontal Stress, Hanjie Chen May 1999

Stress Analysis In Longwall Entry Roof Under High Horizontal Stress, Hanjie Chen

Graduate Theses, Dissertations, and Problem Reports (ETD)

High horizontal stress plays an important role in ground control in longwall mining. It can significantly affect the stability of the panel entry system in both the development and mining periods. Many roof problems have been contributed to high horizontal stress, especially when the immediate roof is weak, or thinly bedded.;In this research, the stress distributions in the entry roof in longwall mining have been studied when the high horizontal stress occurs. Using a three-dimensional finite element method, the stresses in the entry roof have been analyzed for the different cases. It is found that the stress angle is the …

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Electrochemical Treatment Of Metal-Bearing Aqueous Wastes Based On Novel Forms Of Carbon, Yue Xu May 1999

Electrochemical Treatment Of Metal-Bearing Aqueous Wastes Based On Novel Forms Of Carbon, Yue Xu

Graduate Theses, Dissertations, and Problem Reports (ETD)

Electrochemical remediation is an economic approach for long-term clean-up of metal-bearing aqueous wastes because it provides a means of continuous, selective removal of metal contaminants and offers terminal processes for recovery of the metals. In this study, three forms of novel carbon material were tested as electrodes for the removal of heavy metals and radionuclides from aqueous wastes by electrodeposition and/or electrosorption.;Copper and lead ions in aqueous solution were effectively removed by electrodeposition on two of the carbon electrodes. The continuous, single-pass deposition through a small laboratory-scale cell removed 99% of copper and 83-88% of lead, respectively. On the other …

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Dual Fuel Conversion Of A Direct-Injection Diesel Engine, Talus Park May 1999

Dual Fuel Conversion Of A Direct-Injection Diesel Engine, Talus Park

Graduate Theses, Dissertations, and Problem Reports (ETD)

Dual fuel pilot-injected diesel natural gas engines offer significant potential to reduce oxides of nitrogen (NOx) and particulate matter (PK emissions while maintaining diesel-like efficiency. A 1994 Navistar T444E turbocharger V-8 diesel engine was converted to dual fuel diesel and compressed natural gas (CNG). In an attempt to reduce the overall cost and complexity of conversion, the engine was left completely original, including the diesel fuel injection system. Also, for the sake of simplicity, the method of intake manifold fumigation through an IMPCO, Inc. electronic natural gas control valve was chosen to deliver the CNG. A microprocessor-based electronic control unit …

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Four-Stage Activity-Based Costing (Abc) System Modeling And Computer-Based Application Design, Jianxin Zhu May 1999

Four-Stage Activity-Based Costing (Abc) System Modeling And Computer-Based Application Design, Jianxin Zhu

Graduate Theses, Dissertations, and Problem Reports (ETD)

A Four-Stage Activity-Based Costing (4ABC) model and a computer-based system are created in this research to demonstrate the ABC cost allocation process. 4ABC uses four different levels of activity cost driver to allocate the cost from resource to product. These cost drivers are Resource-to-Department Cost Driver, Department-to-Function Cost Driver, Function-to-Activity Cost Drivers and Activity-to-Product Cost Driver. CoA is then categorized into four different activity levels: Department, Function, Activity and Product. The goal is to estimate how much cost represented by activities that a certain type of product absorbs. 4ABC model can trace both indirect cost and direct cost together at …

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Sequential Development Of The Gassaway Structure In Braxton County, West Virginia, Richard Ford Viso May 1999

Sequential Development Of The Gassaway Structure In Braxton County, West Virginia, Richard Ford Viso

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study was undertaken in an effort to reconstruct the development history of the Gassaway dome in Braxton county, West Virginia. Several different analyses were performed to answer questions regarding the timing of the growth of the structure, and mechanisms responsible for the location and shape of the structure.;Interpretation of seismic line CNR-G1 reveals a fan-like distribution of faults (in cross-section), characteristic of strike-slip related positive flower structures. Structure and isopach maps constructed from several hundred wells throughout the study area help constrain the aerial extent of the Gassaway structure, defining it as a dome rather than an anticline. Well …

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Productivity And Economic Growth In The Pittsburgh Region From 1850 To 1900, Benjamin Edward Morton May 1999

Productivity And Economic Growth In The Pittsburgh Region From 1850 To 1900, Benjamin Edward Morton

Graduate Theses, Dissertations, and Problem Reports (ETD)

This research presents an empirical test of the effect of economic growth on productivity in manufacturing within the Pittsburgh region from 1850 to 1900. Theoretical research in economic geography refers to this as Verdoorn's 'law'. The underlying reason for this relationship is the positive impact of economic growth on technological development, which translates into changes in productivity. This study provides an empirical test of this relationship at a very different scale and time frame than previous studies, namely the counties within the Pittsburgh nodal economic region. The period from 1850 to 1900 was one in which the Pittsburgh region developed …

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An Application Of The Delphi Method Of Forecasting To The Future Of Technology Infrastructure In West Virginia High Schools, William H. Carman May 1999

An Application Of The Delphi Method Of Forecasting To The Future Of Technology Infrastructure In West Virginia High Schools, William H. Carman

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study investigated the technology infrastructures that will have an impact on school systems in West Virginia that desire to either retrofit existing high school structures or construct new ones. A three round modified Delphi technique was used to determine the life expectancy and affordability of each technology infrastructure.;In Round 1, surveys were sent via E-mail to 21 individuals representing public education in West Virginia at all levels, colleges and universities, technology business executives, an architect, and a foreign technology business executive. In response to the first survey, the expert panel generated a total of twenty-one different technology infrastructures that …

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The Implementation Of Learning Strategies In The Design Of An On-Line Medical Course Supplement, Lee Ann Hill May 1999

The Implementation Of Learning Strategies In The Design Of An On-Line Medical Course Supplement, Lee Ann Hill

Graduate Theses, Dissertations, and Problem Reports (ETD)

Given the charge of integrating technology in the medical school curriculum, faculty members are faced with the challenge of designing new materials for their courses. Often, these materials become on-line resources such as hypermedia and electronic communication. Strategies may assist students who are unfamiliar with on-line materials to use such materials more effectively. This study investigated the elaborative interrogation strategy used in conjunction with on-line materials to promote more efficient processing of difficult material. Twenty second-year medical students volunteered to participate in the study. The course in which they were enrolled required the use of an on-line lecture supplement. The …

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In -Cylinder Combustion -Based Virtual Emissions Sensing, Michael L. Traver May 1999

In -Cylinder Combustion -Based Virtual Emissions Sensing, Michael L. Traver

Graduate Theses, Dissertations, and Problem Reports (ETD)

The development of a real-time, on-board measurement of exhaust emissions from heavy-duty engines would offer tremendous advantages in on-board diagnostics and engine control. In the absence of suitable measurement hardware, an alternative approach is the development of software-based predictive approaches. This study demonstrates the feasibility of using in-cylinder pressure-based variables as the inputs to predictive neural networks that are then used to predict engine-out exhaust gas emissions. Specifically, a large steady-state engine operation data matrix provides the necessary information for training a successful predictive network while at the same time eliminating errors produced by the dispersive and time-delay effects of …

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A Discrete Choice Based Facility Location Model For Inland Container Depots., Yuanquan Xu Jan 1999

A Discrete Choice Based Facility Location Model For Inland Container Depots., Yuanquan Xu

Graduate Theses, Dissertations, and Problem Reports (ETD)

Container transport operations have been extending inland, providing more comprehensive service across the shipping network. Accordingly, container transport operators are making extensive capital investments in deploying inland container depot (ICD) networks. Optimizing the location of such facilities financially is vital for both capital and operating efficiencies. Currently, there are no models at the regional network level to guide container operators in locating ICDs on their networks. This research studies the ICD location problem and develops a comprehensive ICD location model. Based on comprehensive analysis of the container transport industry, focusing on ICD operations, this thesis developed a useful formulation of …

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The Analysis Of Pipeline Leak Tests Using Degadis Model., Alexander Chamorro Jan 1999

The Analysis Of Pipeline Leak Tests Using Degadis Model., Alexander Chamorro

Graduate Theses, Dissertations, and Problem Reports (ETD)

Pipeline leaks are of major concern to natural gas industry. They can result in loss of revenue, potential danger to public, and environmental damage. To ensure pipeline safety and reliability, a ground surveillance program to detect leaks is conducted on annual basis. Considering the number of miles of natural gas pipeline, this method is time consuming and expensive. There has been interest in developing other methods for rapid survey of natural gas pipelines. An aerial pipeline leak detection system has been developed recently that utilizes an aircraft equipped with flame ionization hydrocarbon detector for analyzing the samples taken over the …

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Assertion Seeding: Development Of Program Instrumentation Through Iterative Formal Analysis., Vikram Nagulakonda Jan 1999

Assertion Seeding: Development Of Program Instrumentation Through Iterative Formal Analysis., Vikram Nagulakonda

Graduate Theses, Dissertations, and Problem Reports (ETD)

Model Checking has been successfully used for validating the requirements of concurrent systems, but validating requirements does not guarantee a sound implementation. We combine the power of model checking with source code assertions to verify concurrent systems. Assertions have been used for detecting software faults during debugging and for run-time checking in production releases of software. We developed the Model-based Assertion Generator and Extraction Tool (MAGET) to extract a PROMELA state model from an assertion-annotated Java program. The extracted model is then validated against properties specified in linear temporal logic (LTL) and the results of the validation process are used …

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The Effect Of Diet Dilution With Lactose On The Performance Of Turkeys., Melvin Fungayi Simoyi Jan 1999

The Effect Of Diet Dilution With Lactose On The Performance Of Turkeys., Melvin Fungayi Simoyi

Graduate Theses, Dissertations, and Problem Reports (ETD)

An experiment involving 96 turkeys was carried out in conventional battery cages. The purpose of this experiment was to determine the effect of lactose on the productive performance of turkeys. Another objective was to establish the optimum level of inclusion in the diet. Birds were housed two per cage from day-old to six weeks old. Diets, containing 0, 0.5, 1, 2, 4 and 8% lactose, and water were offered ad libitum throughout the trial. The highest average weight gain per cage (3.79Kg) was recorded in birds on the 4% lactose diet. There was significant difference (p < 0.01) in weight gain per cage between birds on the 4% and those on the 0% lactose diet (control). All birds on lactose diets were more feed efficient than those on the control diet. Diet did not affect fecal DM but caused high fecal DAPA content (p < 0.05) in 4% lactose birds.

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The Origins Of Rapids In The Lower New River Gorge, West Virginia., Dawn Anne Moore Jan 1999

The Origins Of Rapids In The Lower New River Gorge, West Virginia., Dawn Anne Moore

Graduate Theses, Dissertations, and Problem Reports (ETD)

Rapids occur where supercritical flow conditions are present (Kieffer, 1985). Supercritical flow, resulting from a local decrease in stream depth or acceleration in flow, is commonly produced where voluminous surficial deposits or bedrock outcrops constrict the stream channel. Mapping at 1:10,000-scale shows that most rapids in the lower New River Gorge, are a result of surficial deposits, including valley-wall mass movement, tributary debris fans, and alluvium. Few rapids occur at bedrock outcrops. Half of the rapids are predominantly the result of valley-wall mass movement, including debris flow, rock fall, and debris slide/complex failures. Tributary debris-fan deposits, derived from debris flows …

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An Investigation Of Carbon Residue From Pyrolyzed Scrap Tires., Bhagat Chandra Bandlamudi Jan 1999

An Investigation Of Carbon Residue From Pyrolyzed Scrap Tires., Bhagat Chandra Bandlamudi

Graduate Theses, Dissertations, and Problem Reports (ETD)

The objectives of this study are: (1) Blending the Conrad residue with coal derived pitches and its effect on the pitch properties. (2) The activation of the Conrad residue with carbon dioxide. (3) Assessment of the relationship between surface area of the activated residue and extent of activation. The Conrad residue is blended with a hydrogenated coal pitch and a commercial coal-tar binder pitch. The particle size of the residue is too large to produce the desired degree of isotropy. Moreover, coking of the coal-tar mixture yields a carbon foam whose density is proportional to the amount of residue. The …

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A Study Of Paraffin Deposition And Removal Characteristics Of Jacksonburg-Stringtown Oil, West Virginia., Furqan Ul Haq Jan 1999

A Study Of Paraffin Deposition And Removal Characteristics Of Jacksonburg-Stringtown Oil, West Virginia., Furqan Ul Haq

Graduate Theses, Dissertations, and Problem Reports (ETD)

Laboratory experiments were carried out in order to validate the critical model of wax deposition. Results are presented in the form of time evolution of axial distribution of temperature and layer thickness. It is shown that the simple laboratory model of cold spot test is capable of predicting the order of magnitude of deposition. Experimental results also detail the effectiveness of chemical additives, which acts as inhibitors to wax deposition. Dissipation by these organic solvents is studied for effectiveness at various additive to crude ratios and binary mixtures of additives at various mole fractions. The screening tests of chemical additives …

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