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Graduate Theses, Dissertations, and Problem Reports (ETD)

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Simulation Of A Vertical Ground-Coupled Heat Pump System With Optimal Ground Loop Design, Krishna C. Adivi Aug 2003

Simulation Of A Vertical Ground-Coupled Heat Pump System With Optimal Ground Loop Design, Krishna C. Adivi

Graduate Theses, Dissertations, and Problem Reports (ETD)

As the natural resources for conventional energy will steadily diminish in the future, it becomes necessary to search for alternate sources of energy. One of those sources includes the geothermal energy, which is defined as the thermal energy found in the earth's crust. Ground coupled heat pumps (GCHP) consist of a water-to-air or water-to-water heat pump, a circulator pump, a buried pipe grid and an interconnecting header. Heat is extracted from or rejected to the ground through this buried pipe grid that circulates a heat transfer fluid such as water or a water/antifreeze solution. Energy is spent to run the …

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Evaluation Of Regulated Emissions From Heavy-Duty Diesel Vehicles In The South Coast Air Basin, Thomas M. Buffamonte Aug 2003

Evaluation Of Regulated Emissions From Heavy-Duty Diesel Vehicles In The South Coast Air Basin, Thomas M. Buffamonte

Graduate Theses, Dissertations, and Problem Reports (ETD)

It is important to know how heavy-duty diesel vehicles affect the air quality in the United States. Twenty-five heavy-duty diesel vehicles in the CRC E55/59 Phase I study were tested on the Urban Dynamometer Driving Schedule (UDDS), AC50/80 and the Heavy Heavy-Duty Diesel Truck (HHDDT) Schedule using the West Virginia University Transportable Emissions Laboratory (TransLab). Every vehicle in the CRC E55/59 Phase I study was tested at 30,000 lbs. (Unladen) and 56,000 lbs. (Laden) on the HHDDT, except for one tanker truck that was tested at 45,000 lbs (Laden). Also, the first thirteen vehicles in the study were tested on …

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Strengthening Historic Covered Bridges To Carry Modern Traffic, Rex A. Cyphers Aug 2003

Strengthening Historic Covered Bridges To Carry Modern Traffic, Rex A. Cyphers

Graduate Theses, Dissertations, and Problem Reports (ETD)

The focus of this study was to develop means and methods to strengthen timber superstructural components of historic covered bridges using Glass Fiber Reinforced Polymer (GFRP) composite materials. The strengthening methodologies developed during this research project were designed to conform to the Secretary of the Interior's Standards for the Treatment of Historic Properties. More specifically, tension and bending tests were conducted to establish bond strength of GFRP rebars embedded in wood, and to establish bending strength and stiffness of large-scale beams reinforced with GFRP pultruded plates, and GFRP rebars. The GFRP rebars were developed to be used specifically as reinforcing …

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Effect Of In-Situ Stresses On The Stability Of Coal Mine Development Workings, Murali Mohan Gadde Aug 2003

Effect Of In-Situ Stresses On The Stability Of Coal Mine Development Workings, Murali Mohan Gadde

Graduate Theses, Dissertations, and Problem Reports (ETD)

Among the different types of ground control problems associated with underground coal mining, those related to in-situ stresses are the most common ones affecting the safety of a mining operation. As a result, this has been the focus of many ground control research works done in the recent years. More work has been done in this thesis to add additional information on the in-situ stress related ground control issues of the underground coal mine development workings.;Three-dimensional finite element modeling has been done to examine the Influence of the in-situ maximum horizontal stress angle on the stability of both the entry …

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Estimating Reliability Impact Of Biometric Devices In Large Scale Applications, Karthikeyan Mahadevan Aug 2003

Estimating Reliability Impact Of Biometric Devices In Large Scale Applications, Karthikeyan Mahadevan

Graduate Theses, Dissertations, and Problem Reports (ETD)

In the last two decades, there has been a tremendous growth of biometric applications especially in security. Reliability of the biometric devices is extremely important.;This thesis discusses an approach for estimating the reliability of systems, which contain biometric user authentication subsystem. The ECRA (Early Component Based Reliability Assessment) tool utilizes an easy to use interface and employs the Bayesian algorithm to predict the system reliability. This application of the ECRA technique to biometrics is new. Using the UML diagrams and the ECRA tool, the reliability of the system is predicted.

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Performance Of Doweled Concrete Joints Subjected To Fatigue Loading, Appalaraju Vetsa Aug 2003

Performance Of Doweled Concrete Joints Subjected To Fatigue Loading, Appalaraju Vetsa

Graduate Theses, Dissertations, and Problem Reports (ETD)

Distress in concrete transverse joints is often initiated due to the development of excessive stresses at the dowel/concrete interface. Recent studies indicated the existence of two types of stresses i.e. compressive stresses at the top and bottom of the dowel and tensile stresses at both sides of the dowel bar. These stresses are the primary concern as they are believed to be a major factor for the failure of rigid pavement joints.;Dr. Shoukry invented a new dowel design named shokbar that significantly reduces the magnitude of such contact stresses. The primary objective of this study is to characterize the behavior …

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Soil Compaction Caused By Timber Harvesting In Central Appalachian Hardwood Forests, Mark W. Jones May 2003

Soil Compaction Caused By Timber Harvesting In Central Appalachian Hardwood Forests, Mark W. Jones

Graduate Theses, Dissertations, and Problem Reports (ETD)

Two commonly used harvesting systems in central Appalachia were examined to determine the amount of soil compaction associated with each harvest type. A manual system of chainsaw and cable skidder, along with a mechanized system consisting of feller-buncher and grapple skidder were monitored in two central Appalachian hardwood forest sites. Examinations of soil bulk density (lbs/ft 3) were made pre-harvest and post-harvest for each harvest unit. Observations were conducted along the skid roads in conjunction to distance from the landing. Sample points were also taken systematically through each harvest site. The physical condition was recorded using a nuclear density probe. …

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Comparison Of Concentrations In The Breathing Zone, Santosh Raghavendra Kulkarni May 2003

Comparison Of Concentrations In The Breathing Zone, Santosh Raghavendra Kulkarni

Graduate Theses, Dissertations, and Problem Reports (ETD)

The concentrations in the "breathing zone" were analyzed on three human subjects in simulating work conditions. The experiments were carried out in a wind tunnel having 40&feet; x 12&feet; x 9&feet; dimensions. Ethanol vapor mixed with nitrogen was used as a tracer gas. Samples were taken at the forehead, adjacent to the nose (nose), the mouth, neck, chest, right lapel, left lapel. Nose was sampled at l liter per minute (lpm) and 0.15 lpm at different times, while the others were sampled at 0.15 lpm at two different wind tunnel velocities. The source was released at naval height for each …

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Trip Generation Characteristics Of Rural Clinics In West Virginia, Andrew Paul Morgan May 2003

Trip Generation Characteristics Of Rural Clinics In West Virginia, Andrew Paul Morgan

Graduate Theses, Dissertations, and Problem Reports (ETD)

With the decreasing number of hospitals in rural areas, more rural clinics are being established to meet the health care needs in rural areas. Rural clinics are small health care facilities that serve the primary care needs of rural areas. There are currently no published trip generation rates available for rural clinics. The only rates available are those presented for "clinics" in ITE's Trip Generation (1997). These rates are based on very small sample sizes and on facilities that do not adequately reflect the traffic characteristics of rural clinics.;Trip generation rates were developed for rural clinics in West Virginia. Traffic …

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Pronunciation Difficulties In The Consonant System Experienced By Arabic Speakers When Learning English After The Age Of Puberty, Ana Marina Do Val Barros May 2003

Pronunciation Difficulties In The Consonant System Experienced By Arabic Speakers When Learning English After The Age Of Puberty, Ana Marina Do Val Barros

Graduate Theses, Dissertations, and Problem Reports (ETD)

The current study investigates the difficulties Arabic speakers may encounter when pronouncing English consonants. All participants are adults who have been in contact with the American culture for at least four years. The results show that the Arabic speakers in this study had difficulties to pronounce eight English consonants. The results also demonstrate that the difficulties experienced by Arabic speakers may differ depending on the country they come from. For instance, a person from Kuwait may experience different problems with English consonants when compared to a person from Egypt. This study provides insights and assists ESL teachers with the development …

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Modeling Of Product Variability In Fluidized Bed Coating Equipment, Ku Zilati Ku Shaari May 2003

Modeling Of Product Variability In Fluidized Bed Coating Equipment, Ku Zilati Ku Shaari

Graduate Theses, Dissertations, and Problem Reports (ETD)

Particle coating in fluidized bed equipment is common practice for improving the properties of solid products, particularly in the pharmaceutical, food and agricultural industries. In this thesis, the application of particle coating to pharmaceutical products utilizing the Wurster-column coating process is addressed. This technique is extensively used in the pharmaceutical industry for precision drug coating and modified release coating of tablets and pellets.;The simulation of particle movement in fluidized beds has been successfully developed using Monte Carlo simulation. Raw velocity and voidage data for each region of a semicircular fluidized bed, obtained by Subramanian (2001), are used in the simulation. …

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In-Situ, Near Real-Time Acquisition Of Particle Movement In Rotating Drum Coating Equipment, Sandeepa Sandadi May 2003

In-Situ, Near Real-Time Acquisition Of Particle Movement In Rotating Drum Coating Equipment, Sandeepa Sandadi

Graduate Theses, Dissertations, and Problem Reports (ETD)

The uniformity of coating applied to large particles and tablets in rotating-drum coating devices is of significant interest to the Pharmaceutical Industry, especially when the coating contains active material or provides a sustained release barrier for drug transport in a functional coat. As tablets move around the coating drum, they periodically spend time at the surface of the avalanching layer and pass through the spray zone. During this time they receive amounts of coating solution proportional to both the time spent in the spray zone and the area exposed to the spray. The purpose of this research was to quantify …

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Novel Control Design And Strategy For Load Frequency Control In Restructured Power Systems, Dulpichet Rerkpreedapong May 2003

Novel Control Design And Strategy For Load Frequency Control In Restructured Power Systems, Dulpichet Rerkpreedapong

Graduate Theses, Dissertations, and Problem Reports (ETD)

In restructured electric power systems, a number of generation companies and independent power producers compete in the energy market to make a profit. Furthermore, a new marketplace for ancillary services is established, providing an additional profit opportunity for those power suppliers. These services are essential since they help support the transmission of power from energy sources to loads, and maintain reliable operation of the overall system. This dissertation addresses regulation , a major ancillary service also known as the load frequency control (LFC) problem, and presents novel control designs and strategies for the LFC in restructured power systems.;A power system …

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Modeling Of An Aluminum Reduction Cell For The Development Of A State Estimator, Philip Biedler May 2003

Modeling Of An Aluminum Reduction Cell For The Development Of A State Estimator, Philip Biedler

Graduate Theses, Dissertations, and Problem Reports (ETD)

Electrolytic cells are used to produce aluminum from alumina ore. These cells use a carbon anode, a cryolitic bath, and a carbon containment vessel, which also serves as the cathode. The process is not completely understood because of the limited number of measurements and its complexity.;A finite element model was developed that simulates the electrical, thermal, and chemical phenomena occurring within the cell. The model was verified by comparing its output to data presented in the literature, and by comparing its output to data gathered from operating reduction cells at Century Aluminum in Ravenswood, WV. The model was used to …

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Geological Mapping Of Entry Roof In Mines, Quanzhong Gu May 2003

Geological Mapping Of Entry Roof In Mines, Quanzhong Gu

Graduate Theses, Dissertations, and Problem Reports (ETD)

Although strata types and approximate thickness of strata can be obtained from the geological exploration materials of the mine, these do not meet the requirements for roof bolting design because of the ever-changing roof geological properties, including rock strength, discontinuity distribution, and thickness of rock strata. In order to obtain such geological information in a timely manner, the technology of geological mapping of the roof in the mine, which uses the drilling parameters acquired during the drilling process, has been proposed. The study in this dissertation attempts to map the roof geology by developing a new drilling parameter, drilling hardness, …

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Design Considerations For Longwall Yield Pillar Stability, Khaled Morsy Mohamed May 2003

Design Considerations For Longwall Yield Pillar Stability, Khaled Morsy Mohamed

Graduate Theses, Dissertations, and Problem Reports (ETD)

Coal mine bumps have presented serious mining problems in the United States throughout the 20th century. Persistent bump problems not only threaten the safety of miners, but also have caused the abandonment of large coal reserves and have led to premature mine closures. Current application of yield pillars shows that it can prevent coal bumps in some Longwall mines. In this dissertation, the need for a new method to design yield pillars in bump prone conditions is established. In order to fulfill this need, a PC-design program based on finite element modeling was developed. This program can design stable yield …

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Reinforcement And Punishment During Programmed Instruction, Stephen C. Scherer May 2003

Reinforcement And Punishment During Programmed Instruction, Stephen C. Scherer

Graduate Theses, Dissertations, and Problem Reports (ETD)

Recommendations for improving answer accuracy during programmed instruction have included the use of punishment to decrease the rate of students' responding and to prevent careless mistakes. The effects of punishment during programmed instruction, however, have not been clearly identified. There is evidence that punishment increases attention and decreases response rates during learning tasks, but other effects on student responding, including escape from the learning task, have not been systematically examined. The present study was designed to systematically examine the effects of punishment as well as extinction during programmed instruction. Four college students were recruited to earn money while working on …

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Mesomechanics Of Fabric Reinforced Composites, Thomas Miles Damiani May 2003

Mesomechanics Of Fabric Reinforced Composites, Thomas Miles Damiani

Graduate Theses, Dissertations, and Problem Reports (ETD)

Fiber reinforced plastic composites are an attractive alternative to traditional materials because of, among other things, the ability to concurrently design the materials and ratios to fit a specific need. One method of fiber reinforcement is through the used of woven fabrics, which provide more balanced overall strengths and durability during fabrication. The weaving and interlacing of the fibers, however, adds a level of complexity when predicting material properties and strengths using micromechanical models. Traditional models have mostly been based on classical thin lamination theory, and this method is limited in its scope and applicability for woven fabric composites. This …

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Implementation And Application Of Nde On Ceramic Candle Filters, Alejandro C. Kiriakidis May 2003

Implementation And Application Of Nde On Ceramic Candle Filters, Alejandro C. Kiriakidis

Graduate Theses, Dissertations, and Problem Reports (ETD)

A nondestructive evaluation (NDE) technique has been developed to determine the deterioration and remaining life of full-size ceramic candle filters used at the Power System Development Facility (PSDF) in Alabama. Ceramic candle filters are hollow cylindrical structures made of porous ceramic materials used in advanced coal-fired power generation systems. They protect power plant's gas turbine components from damage due to erosion. In general, advanced coal-fired power systems operational conditions include extreme thermal/pressure environment and vibration-induced stresses over a great period of time. The knowledge of the dynamic behavior of ceramic candle filters is essential and can be used to measure …

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Modular Track Panels For Improved Safety In The Mining Transportation Industry, Donald Sterling Tusing May 2003

Modular Track Panels For Improved Safety In The Mining Transportation Industry, Donald Sterling Tusing

Graduate Theses, Dissertations, and Problem Reports (ETD)

Locomotives and "mine cars" often derail (often two or three times daily) in coalmines causing fatal injuries, fires initiated from sparks during derailment, and costly downtimes. Modular track panels (resembling the ladder track systems used in Japan) were designed and tested for bending behavior and load sharing characteristics, between track modules and also between rails, to improve safety of miners during transportation. Prefabricated track modules made of prestressed concrete and fiber reinforced polymer (FRP) composites were evaluated. Two modular prestressed concrete modules, each 15 ft long, were tested, as well as one set of prestressed concrete half-panels to test the …

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Evaluation Of The Effect Of Fines On Asphalt Concrete, Carlos Humberto Reyes May 2003

Evaluation Of The Effect Of Fines On Asphalt Concrete, Carlos Humberto Reyes

Graduate Theses, Dissertations, and Problem Reports (ETD)

Several methods have been developed for determining the quantities of aggregate and asphalt cement used in asphalt concrete. This research consists of the evaluation of the surface area of different aggregates used in the state of West Virginia. This factor is important because the amount of asphalt needed to coat the aggregate depends on the specific surface area of the aggregate blend. The specific surface area of the aggregate blend is usually calculated based on the aggregate gradation and surface area factors.;This research proposes a method to obtain accurate specific surface area factors using the Blaine air permeability apparatus. By …

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Application Of Statistical Methods For "Flow Unit" Identification And Characterization Of A Reservoir Using Well Log And Core Data, Reza Mustafa May 2003

Application Of Statistical Methods For "Flow Unit" Identification And Characterization Of A Reservoir Using Well Log And Core Data, Reza Mustafa

Graduate Theses, Dissertations, and Problem Reports (ETD)

A flow unit is a stratigraphically continuous interval of similar reservoir process speed that maintains the geologic framework and characteristics of rock types. Permeability and porosity of the reservoir rock has always been considered as two of the most important parameters to identify flow unit for formation evaluation, reservoir description, and characterization. Beyond evaluating permeability and porosity, one can also use combinations of two or more rock properties to gain insight into the character of two through porous media. Porosity is commonly evaluated from the well log data, which are usually available from the most wells in the reservoir. But …

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Durability Of Concrete Beams With Frp Wraps, Woraphot Prachasaree May 2003

Durability Of Concrete Beams With Frp Wraps, Woraphot Prachasaree

Graduate Theses, Dissertations, and Problem Reports (ETD)

This research focuses on the durability of carbon FRP (CFRP) wraps bonded to concrete beams under accelerated and natural aging. Variation in mechanical properties of CFRP wrapped concrete beams due to aging through water immersion, salt and alkaline solution immersion at elevated and freeze-thaw temperature variation are studied. Different parameters evaluated during beam bending tests are: maximum load (moment), deflections, crack width, and deformability factor. Accelerated aging was carried out on 5"x8"x60" wrapped beams under: (1) water immersion at room, 110°F and 140°F temperatures; (2) alkaline and salt solution at room temperature; (3) alkaline and salt solution at freeze-thaw temperature. …

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Finite Element Analysis Of Cell Subjected To Compressive Loading, Vidhyashankar Venkatesan May 2003

Finite Element Analysis Of Cell Subjected To Compressive Loading, Vidhyashankar Venkatesan

Graduate Theses, Dissertations, and Problem Reports (ETD)

A 3D finite element model was built to study the mechanical response of the cell to load. The model included major structural components of a cell like cytoskeletal elements, cell membrane and the presence of internal fluid pressure. The cell was considered as a pressurized, fluid filled bag where inflation of the cell membrane is resisted by the cytoskeletal elements. The behavior of the cell model with microtubules prone to buckling and stabilized by actin filaments was also studied.;A point load was applied to a microtubule in a cell model with there buckling effect taken into consideration. The microtubule started …

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Performance Evaluation Of Diesel Particulate Filters On Heavy-Duty Vehicles, Stephen George Rosepiler May 2003

Performance Evaluation Of Diesel Particulate Filters On Heavy-Duty Vehicles, Stephen George Rosepiler

Graduate Theses, Dissertations, and Problem Reports (ETD)

Diesel particulate filters, or DPFs, are exhaust aftertreatment devices used to reduce exhaust emissions from diesel powered vehicles. Typical designs have a wall flow filter element downstream of an oxidation catalyst, which oxidizes a portion of the NO present in the exhaust stream to form NO2. The resulting NO2 aides in the combustion of the soot collected in the wall flow filter element allowing for the complete breakdown of the soot within typical diesel exhaust temperatures, thus limiting the required maintenance on the filter elements to the removal of non-combustible ash.;Three aspects of DPF performance were investigated: cold start performance, …

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Moisture Diffusion Through Neat And Glass-Fiber Reinforced Vinyl Ester Resin Containing Nanoclay, Hiteshkumar T. Rana May 2003

Moisture Diffusion Through Neat And Glass-Fiber Reinforced Vinyl Ester Resin Containing Nanoclay, Hiteshkumar T. Rana

Graduate Theses, Dissertations, and Problem Reports (ETD)

Moisture diffusion was studied through neat resin as well as glass-fiber reinforced vinyl ester samples, both containing up to 5 wt% montmorillonite clay. Transient and steady-state diffusion experiments were carried out with both neat resin as well as glass-fiber reinforced samples. Effect of saline and alkaline solutions on the process of diffusion was studied. It was found that the diffusivity decreased due to the presence of nanoclay in polymer. SEM images of FRPs were taken after two months of immersion in distilled water at room temperature. The SEM images revealed that the presence of clay indeed protected the glass-fibers. Effect …

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Investigation Of Ship Wakes Using Les With Various Sgs Models, Zeynep N. Cehreli May 2003

Investigation Of Ship Wakes Using Les With Various Sgs Models, Zeynep N. Cehreli

Graduate Theses, Dissertations, and Problem Reports (ETD)

Turbulence plays an important role in ship wake flows. Without the knowledge of turbulent intensities and length scale information it is virtually impossible to model and predict turbulence characteristics in complex flows, such as ship wake flows. Moreover, the behavior of ship wakes requires an understanding of the turbulence near a free surface. The present study will focus on identifying the contributions of various mechanisms, but primarily that of the free surface, to the process of turbulence generation and dissipation in the wake of a turning ship using the large eddy simulation (LES) technique. LES is applied in conjunction with …

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Seasonal Movement And Macro-Habitat Use Of Largemouth Bass (Micropterus Salmoides) In An Ohio River Navigation Pool, Jason Gregory Freund May 2003

Seasonal Movement And Macro-Habitat Use Of Largemouth Bass (Micropterus Salmoides) In An Ohio River Navigation Pool, Jason Gregory Freund

Graduate Theses, Dissertations, and Problem Reports (ETD)

Largemouth bass provide an important recreational fishery in the Ohio River. Our objectives were to determine critical over-wintering and spawning habitats of largemouth bass in the Belleville Pool of the Ohio River. We surgically implanted radio-transmitters in 39 adult largemouth bass and tracked them over a 23-month period. Our results demonstrate the importance of off-channel habitats in the life history of largemouth bass in large river systems. Sedimentation, resulting in a loss of embayment quality and surface area, is an important problem and thus merits increased attention. Restoration and protection efforts to improve largemouth bass fisheries in large river systems …

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Wildlife Use And Habitat Quality Of Back Channel Areas Associated With Islands On The Ohio River, West Virginia, Andrew Karl Zadnik May 2003

Wildlife Use And Habitat Quality Of Back Channel Areas Associated With Islands On The Ohio River, West Virginia, Andrew Karl Zadnik

Graduate Theses, Dissertations, and Problem Reports (ETD)

The islands and associated back channels on the Ohio River have long been thought to provide important habitat characteristics for riparian wildlife. However, few studies have quantitatively evaluated this importance. As pressure continues to develop back channel areas for commercial and residential use, quantitative information is vital for natural resource managers to justify conserving these areas for wildlife. The goals of my study were to quantify wildlife use of back and main channels relative to waterbirds, anurans, turtles, and riparian furbearing mammals, and to evaluate the habitat quality of back and main channels through the use of habitat suitability index …

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Characterization Of Wetland Soils In The Beaver Creek Watershed, Kyle Michael Stephens May 2003

Characterization Of Wetland Soils In The Beaver Creek Watershed, Kyle Michael Stephens

Graduate Theses, Dissertations, and Problem Reports (ETD)

A proposed section of Appalachian Corridor H will pass through an area of the Beaver Creek watershed in Tucker County, West Virginia previously mined for the acid-producing Upper Freeport coal. Presently, partially-reclaimed spoils from past mining activities are generating acid mine drainage and releasing sediments into streams and other water bodies. Soils of acid mine drainage impacted wetlands and non-impacted wetlands were characterized to establish baseline soil status and to gain a better understanding of the chemical and physical processes occurring in these wetlands. The results of this study will be used to assist the West Virginia Division of Highways …

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