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2000

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Job's Syndrome, M A. Yousafzai, K Nasim, S Q. Nizami Dec 2000

Job's Syndrome, M A. Yousafzai, K Nasim, S Q. Nizami

Department of Paediatrics and Child Health

No abstract provided.

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Surface Segregation And Restructuring Of Colossal-Magnetoresistant Manganese Perovskites La0.65Sr0.35Mno3, Hani Dulli, Peter A. Dowben, Sy-Hwang Liou, E. Ward Plummer Dec 2000

Surface Segregation And Restructuring Of Colossal-Magnetoresistant Manganese Perovskites La0.65Sr0.35Mno3, Hani Dulli, Peter A. Dowben, Sy-Hwang Liou, E. Ward Plummer

Department of Physics and Astronomy: Faculty Publications

We have investigated the surface chemical composition of crystalline films of La0.65Sr0.35MnO3 by angle-resolved x-ray photoelectron spectroscopy. The surface composition was found to be significantly different from that of the bulk because of an appreciable Sr segregation. Furthermore, our study suggests that this Sr segregation has caused a major restructuring of the surface region characterized by the formation of a Ruddlesden-Popper phase (La,Sr)n+1MnnO3n+1 with n = 1. Segregation and restructuring in the surface region should be common in these doped perovskites and will have a profound impact on the electronic …

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Assessment Of Small Mammal Populations In Two Southeastern Forests Of Big Ridge In Chattanooga, Tn, Melissa R. Dickinson Dec 2000

Assessment Of Small Mammal Populations In Two Southeastern Forests Of Big Ridge In Chattanooga, Tn, Melissa R. Dickinson

Masters Theses and Doctoral Dissertations

Field research was conducted to test for effects of urbanization on small mammal abundance and diversity. Preliminary studies were preformed to test sampling techniques and acquire a sample size estimate for the primary study. Sampling sites were chosen in old growth and mixed hardwood forest areas. Six day sampling periods consisted of differing densities and setups of Sherman and pitfall traps within 0.16-ha plots. Data was not statistically analyzed due to minimal sample sizes. Comparable 1.28-ha mixed hardwood forest study sites were chosen in the Big Ridge area of Chattanooga, Tennessee for the primary study. One site had protected status, …

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A Comparison Of The Characteristics Of Gardeners, Their Motivations For Gardening And Management Practices Of Blackacre Community Garden And Limerick Community Garden In Jefferson County, Kentucky., Robin Oxnard Grossman 1974- Dec 2000

A Comparison Of The Characteristics Of Gardeners, Their Motivations For Gardening And Management Practices Of Blackacre Community Garden And Limerick Community Garden In Jefferson County, Kentucky., Robin Oxnard Grossman 1974-

Electronic Theses and Dissertations

Using four surveys, two created by this researcher, another created by Walizcek, Mattson, and Zajicek, and a fourth created by Herbach, the researcher compared the characteristics of community gardeners, their motivations for gardening, and the management practices of the inner-city Limerick Community Garden and the suburban Blackacre Community Garden in Jefferson County, Kentucky. 33 Blackacre gardeners, 16 Limerick gardeners, two garden managers, and two garden administrators participated in the study. The researcher hypothesized that the location of the garden could be influential in determining who the gardeners are and what their motivations for gardening are. The inner-city garden was expected …

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Synthesis And Characterization Of Functionalized Zirconium Pendent Polyamic Acids And Polyimides Based On 3,4'-Oda And Odpa, Wei Wang Dec 2000

Synthesis And Characterization Of Functionalized Zirconium Pendent Polyamic Acids And Polyimides Based On 3,4'-Oda And Odpa, Wei Wang

Theses

The objective of this thesis is to synthesize functionalized zirconium complex pendent polyamic acids and polyimides, then compare their characteristics, e.g. thermal properties, atomic oxygen resistance, and film properties (adhesion, flexibility, and solvent resistance). Towards this end, five different zirconium complexes were attached to the polyamic acid, which is based on 3,4'-oxydianiline (3,4'-0DA), 4,4'-oxydiphthalic anhydride (ODPA), and mellitic dianhydride (MADA), in the presence of dicyclohexylcarbodiimide (DCC). The resulting zirconium complex pendent polyamic acids and the parent polyamic acid were cast onto glass substrates, then thermally imidized by heating at 100C, 200C, and 300C for one hour each. The synthesized zirconium …

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Ostensible Abductions, Real Anthropology, Timothy F. Mccauley Dec 2000

Ostensible Abductions, Real Anthropology, Timothy F. Mccauley

Masters Theses

A gap has developed in the research agenda of contemporary anthropology with regard to a phenomenon which has received notable attention from research professionals in other fields, such as history and psychiatry. What has been called the "alien abduction phenomenon" has had considerable impact, not only on those who sincerely believe these events are an everyday part of human experience (called "abductees") but also on the changing tapestry of American culture. Alien abduction accounts are closely related to the Unidentified Flying Object (UFO) phenomenon, a theme which has shaped American culture since the tum of the century. This thesis represents …

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Factors Influencing Brook Trout (Salvelinus Fontinalis ) Abundance In Forested Headwater Streams With Emphasis On Fine Sediment, James Philip Hakala Dec 2000

Factors Influencing Brook Trout (Salvelinus Fontinalis ) Abundance In Forested Headwater Streams With Emphasis On Fine Sediment, James Philip Hakala

Graduate Theses, Dissertations, and Problem Reports (ETD)

The influence and relative importance of fine sediment on wild brook trout (Salvelinus fontinalis) population size was assessed. Brook trout production in headwater streams was inversely proportional to substrate permeability in one of two years, suggesting substrate composition influenced production. Results suggest the critical fine sediment size for brook trout in this study, is between 0.063 mm and 1.0 mm. Further, fine sediment (<0.063 mm) should not exceed 0.6--1.0% of spawning substrate, or negative population effects may be incurred. Under normal flow conditions, fine sediment was a principal determinant of juvenile trout abundance relative to other physical and biological factors. Adult trout abundance was principally a function of stream discharge, and is potentially further influenced by fine sediment impacts on juvenile recruitment. Spatially restricted food resources, created by drought-induced low flows in year 2 of the study, are believed to have over-powered mechanisms influencing trout abundance under normal flows.

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Diversity Of Ectomycorrhizal Fungi On Two Reclaimed Surface Mines Differing In Soil Properties, Betsy S. Kurnik Dec 2000

Diversity Of Ectomycorrhizal Fungi On Two Reclaimed Surface Mines Differing In Soil Properties, Betsy S. Kurnik

Graduate Theses, Dissertations, and Problem Reports (ETD)

I analyzed community structure of ectomycorrhizal fungi on white pine (Pinus strobus) on two reclaimed surface mines in eastern Ohio. One site was acidic and metal-stressed, the other was alkaline. Completely different community composition was found on the two sites by PCR/ITS/RFLP analyses of field collected mycorrhizae. However, Shannon-Wiener index values indicated that the two communities were equally diverse. A population of isolates of one species common to both sites was obtained from trap cultures planted with white pine. The identity of this species as Wilcoxina mikolae was established through DNA sequencing of the ITS region. The W. mikolae populations …

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Subjective Norms, Attitudes, Body Mass Indices, And Self Esteem As Influences On Women's Body Image Behavior, Amy Martha Rogers Dec 2000

Subjective Norms, Attitudes, Body Mass Indices, And Self Esteem As Influences On Women's Body Image Behavior, Amy Martha Rogers

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to demonstrate associations between perception of body image among women and their body image behaviors. A study was needed to determine the extent to which subjective norms, attitudes, beliefs, Body Mass Index, and self esteem were associated with body image behaviors. The target population in this study was female students at West Virginia University. Data collection was facilitated through an anonymous mailed questionnaire sent to 400 female students at West Virginia University. Components of Theory of Reasoned Action were used to develop a questionnaire. Questions assessed participants' attitudes and beliefs, subjective norms, and outcomes …

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Removal Of Uranium From Aqueous Wastes Using Electrically Charged Carbon Nanofibers, Shannon Lee Stover Dec 2000

Removal Of Uranium From Aqueous Wastes Using Electrically Charged Carbon Nanofibers, Shannon Lee Stover

Graduate Theses, Dissertations, and Problem Reports (ETD)

The presence of aqueous uranium wastes is a problem in the United States and their treatment/disposal is desirable. Treatment methods have been developed but result in concentration opposed to conversion to a disposable form. This technique involves recovery of uranium as a solid, providing an advantage over other methods. The technique utilizes carbon nanofibers as electrodes which successfully electrosorb uranium ions. Fibers with varying surface characteristics were evaluated in the removal process and all were determined to be equally and extremely effective. Various experimental parameters were evaluated including applied potential, pH, and flow rate. The critical applied potential at which …

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Investigation And Simulation Of The Planetary Combination Hybrid Electric Vehicle, Csaba Toth-Nagy Dec 2000

Investigation And Simulation Of The Planetary Combination Hybrid Electric Vehicle, Csaba Toth-Nagy

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was the detailed examination of a Planetary Combination Hybrid Electric Vehicle design (PC-Hybrid). The PC-Hybrid unites all the advantages of the existing hybrid electric vehicle powertrain concepts, such as series, parallel and combination, while eliminating the disadvantages of each.;The PC-Hybrid powertrain is built up of an internal combustion engine, and two electric motor/alternators connected together via a planetary gear set. Several different powertrain configuration layouts were investigated as possible setups of the PC-Hybrid and the two most promising ones were chosen for further investigation and simulation. A control strategy has been developed for the optimal …

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Exploring Visitor Meanings Of Place In The National Capital Parks - Central, Wei-Li Jasmine Chen Dec 2000

Exploring Visitor Meanings Of Place In The National Capital Parks - Central, Wei-Li Jasmine Chen

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study uses a new approach to interpretative research based on (1) understanding the meanings visitors attach to park resources, and (2) examining the connections that visitors made after attending an on-site interpretive program. The study was conducted at the National Capital Parks in Washington, DC. This study revealed that many visitors to the Lincoln Memorial, the Vietnam Veterans Memorial, and the Korean War Veterans Memorial (i.e. the Triangle) seek something of value for themselves, including everything from connecting with the past and rededicating themselves to the ideals of the nation. The study incorporated mixed method design, including purposeful sampling …

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Optimization Of A Helicon Plasma Source For Maximum Density With Minimal Ion Heating, Matthew M. Balkey Dec 2000

Optimization Of A Helicon Plasma Source For Maximum Density With Minimal Ion Heating, Matthew M. Balkey

Graduate Theses, Dissertations, and Problem Reports (ETD)

Measurements of electron density and perpendicular ion temperatures in an argon helicon plasma are presented for five different antennas: A Nagoya type III antenna, a double-saddle antenna, a 19 cm long m = +1 helical antenna, a 30 cm long m = +1 helical antenna and a 19 cm m = +1 helical antenna with wide straps. Electromagnetic wave measurements in the range from 100 kHz to 50 MHz are also presented for a wide range of plasma parameters. The data show a clear transition between RF power coupling to the plasma to create density and coupling to heat ions. …

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Evaluating Mandatory Parent Education For Divorcing Couples With Children, Brian John Krolczyk Dec 2000

Evaluating Mandatory Parent Education For Divorcing Couples With Children, Brian John Krolczyk

Graduate Theses, Dissertations, and Problem Reports (ETD)

Court-mandated parent education for divorcing parents with children has become a standard practice in recent years. The West Virginia State Legislature voted to mandate parent education programs in all of West Virginia effective January, 2000. Research suggests parental conflict is a major factor contributing to adjustment difficulties reported by children. Generally, parent education programs for divorcing couples with children focus on adjustment issues for parents and children as they navigate a demanding period of family change. A literature review of current parent education programs in the United States revealed programs differ in teaching methods used and curriculum. It is reported …

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Psychophysiological Responses Of Older Adults To An Anxiety -Evoking Stimulus, Angela W. Lau Dec 2000

Psychophysiological Responses Of Older Adults To An Anxiety -Evoking Stimulus, Angela W. Lau

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to clarify the relation between anxiety and physiological responses in older adults as compared to younger adults. Heart rate (HR), skin conductance level (SCL), skin conductance response (SCR), systolic blood pressure (SBP), and diastolic blood pressure (DBP) were obtained before, during, and after exposure to a Stroop color-word naming task and a snake video from 46 female younger adults (age 18--30) and 28 female older adults (age 65--80) who were designated as either snake fearful or snake nonfearful. No significant group differences were observed on physiological measures to baseline one or during the snake …

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Coupled Nonlinear Dynamical Systems, Hongyan Sun Dec 2000

Coupled Nonlinear Dynamical Systems, Hongyan Sun

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this dissertation, we study coupled nonlinear dynamical systems that exhibit new types of complex behavior. We numerically and analytically examine a variety of dynamical models, ranging from systems of ordinary differential equations (ODE) with novel elements of feedback to systems of partial differential equations (PDE) that model chemical pattern formation. Chaos, dynamical uncertainty, synchronization, and spatiotemporal pattern formation constitute the primary topics of the dissertation. Following the introduction in Chapter 1, we study chaos and dynamical uncertainty in Chapter 2 with coupled Lorenz systems and demonstrate the existence of extreme complexity in high-dimensional ODE systems. In Chapter 3, we …

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Burnout, Stress And Social Support Among Doctoral Students In Psychology, Kelli Lee Weaver Dec 2000

Burnout, Stress And Social Support Among Doctoral Students In Psychology, Kelli Lee Weaver

Graduate Theses, Dissertations, and Problem Reports (ETD)

The relationships between burnout, stress, and social support have been evaluated across a number of populations within the helping professions. However, no published studies have addressed the relationships between the aforementioned variables among doctoral students in psychology. As a result, the current study attempted to expand knowledge of the relationships between burnout, stress, and social support specifically among Clinical, Counseling, and School Psychology doctoral students. Results suggested that Clinical, Counseling, and School Psychology doctoral students are generally similar in their reports of burnout, stress, and social support. However, several differences were observed between the groups, and these differences are reported. …

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On The Feasibility Of Integrated Optical Waveguide-Based In Situ Monitoring Of Microelectromechanical Systems (Mems), Kolin Shay Brown Dec 2000

On The Feasibility Of Integrated Optical Waveguide-Based In Situ Monitoring Of Microelectromechanical Systems (Mems), Kolin Shay Brown

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation explores the feasibility of using integrated optical waveguides to measure the motion of microelectromechanical structures (MEMS). MEMS are a class of silicon devices which are being developed as sensors and actuators. Because these free moving structures are fabricated using processes similar to microfabrication, MEMS devices and traditional electronics can be integrated on the same substrate. This merging of the technologies will allow the miniaturization of large scale mechanical systems. A difficulty with MEMS devices is determining the submicron motion. One method of noninvasive measurement is optical measurement. Research focused on the characterization of one particular MEMS device, a …

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Characterization Of A Novel Methyl Radical Source And Related Thin Film Growth Studies, Jeffrey Stephen Gold Dec 2000

Characterization Of A Novel Methyl Radical Source And Related Thin Film Growth Studies, Jeffrey Stephen Gold

Graduate Theses, Dissertations, and Problem Reports (ETD)

An ultrahigh vacuum compatible methyl (CH3) radical source has been developed. The methyl radicals were generated by dc- and microwave-discharge processes in either of two ways. In the first, argon (Ar) or an Ar/Xe mixture was passed through the discharge to produce inert gas metastables that react with methane to produce the desired species. This was referred to as the indirect mode of operation. In the second or direct mode, an inert gas/methane mixture was passed directly through the discharge. The discharge/reaction products were sampled using a skimmer, and the resulting molecular beam was either characterized using a mass spectrometer …

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Design, Construction, And Evaluation Of Coal Extraction Pilot Plant To Manufacture Coal-Based Carbon Pitch, Brian Wayne Bland Dec 2000

Design, Construction, And Evaluation Of Coal Extraction Pilot Plant To Manufacture Coal-Based Carbon Pitch, Brian Wayne Bland

Graduate Theses, Dissertations, and Problem Reports (ETD)

A solvent extraction technique for removing mineral matter, including the inorganic sulfur, from coal has been developed by the Department of Chemical Engineering at WVU. The extraction is preformed at mild conditions (202°C and atmospheric pressure) using the solvent N-Methyl-2-Pyrrolidone (NMP). Laboratory results have shown that this technique yields a clean coal product containing less than 1 percent ash and virtually no inorganic sulfur.;This research was conducted for further process design and economic development of an industrial-scale extraction process.;This research reported the possibility of production scale processing by constructing a pilot plant. The pilot plant was used to explore the …

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Improving The Simulation Of A Waterflooding Recovery Process Using Artificial Neural Networks, Edison Gil Dec 2000

Improving The Simulation Of A Waterflooding Recovery Process Using Artificial Neural Networks, Edison Gil

Graduate Theses, Dissertations, and Problem Reports (ETD)

The waterflood performance of the dual five-spot pilot project in the Stringtown oil field, situated in West Virginia, has been studied. A numerical simulator, called BOAST98, was used for the simulation purposes, after developing a reservoir description.;The producing horizon in the field is the Upper Devonian Gordon sandstone, which is characterized by severe heterogeneity due to the depositional environment. Using available core and log data and geological analysis, a reservoir characterization study was done. A preliminary reservoir description based on log porosity-core permeability correlation was improved by developing Artificial Neural Networks (A.N.N.), which incorporates geophysical well log information. These A.N.N.'s …

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Three-Dimensional Image Reconstruction Of Skeletal Tissue From Computed Tomography, Sundareswar Bangalore Jayashekar Dec 2000

Three-Dimensional Image Reconstruction Of Skeletal Tissue From Computed Tomography, Sundareswar Bangalore Jayashekar

Graduate Theses, Dissertations, and Problem Reports (ETD)

Edge Detection Techniques play a very important role in medical imaging. Pre-operative diagnosis of diseases such as cancer, tumors, bone fractures etc. depend on edge detection techniques to identify the malignant growths. In orthopedics, edge detection techniques are used in the reconstruction of the skeletal system from modalities such as MRI (magnetic resonance imaging) and CT (computed tomography).;In this thesis, we develop a simple process for the three dimensional image reconstruction of the human knee, starting from computed tomography scans. Designing a digital image processing technique which successfully separates the bone from the surrounding flesh and muscle tissue is the …

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Development And Evaluation Of Glass Fiber-Reinforced Composite/Wood Railroad Crossties, Krit Laosiriphong Dec 2000

Development And Evaluation Of Glass Fiber-Reinforced Composite/Wood Railroad Crossties, Krit Laosiriphong

Graduate Theses, Dissertations, and Problem Reports (ETD)

Railroad crossties are strengthened by wrapping glass fiber reinforced composites (GFRC). In addition, durability of crossties has been found to have enhanced by reinforcing them with GFRC wraps. In order to reduce the cost, GFRC wraps are not used to wrap the entire length of a crosstie, but only in the region that holds steel plates. The objective of this research is to select compatible adhesive between creosote treated wood and glass fabric, and study the performance of wrapped wooden crossties.;Five primer/resin combinations (Resorcinol Formaldehyde group) were screened for strength and durability of treated wood crossties. To evaluate stiffness and …

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Carbon Products From Coal Liquefaction Fractions, Lizbeth Laureano-Perez Dec 2000

Carbon Products From Coal Liquefaction Fractions, Lizbeth Laureano-Perez

Graduate Theses, Dissertations, and Problem Reports (ETD)

Processes for coal conversion are being evaluated for the development of carbon-product precursors. In the present work, coal hydrogenation is being considered as a procedure for tailoring the properties of the precursors for specific carbon products. The object of this project is to assess and evaluate such coal-derived materials for use as precursors for the production of carbon products. Coal liquefaction samples are made under various processing conditions, e.g. temperature, pressure, solvent. Softening points, ash content and coking values of the samples are determined at WVU by ASTM methods. These samples were also examined for coke microstructure and mesophase formation. …

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Computational Model Of Ductile Erosion By Single Particle Impact, Chandrakant Rai Dec 2000

Computational Model Of Ductile Erosion By Single Particle Impact, Chandrakant Rai

Graduate Theses, Dissertations, and Problem Reports (ETD)

Erosion by solid particle impact is a common problem in many industrial applications. It results due to mechanical contact between the particle and the metal surface, which in turn result in potential material losses. Erosion of machine parts by the small solid particle entrained in liquid or gaseous working environment is a serious problem in many industrial applications. Numerous experiments have been conducted to obtain empirical relations for predicting material loss due to these impacts and to arrive at an appropriate material for a particular working environment. But with so many new materials being used for different applications, and operating …

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Approaches To Creating Anonymous Patient Database, Shijun Shen Dec 2000

Approaches To Creating Anonymous Patient Database, Shijun Shen

Graduate Theses, Dissertations, and Problem Reports (ETD)

Health care providers, health plans and health care clearinghouses collect patient medical data derived from their normal operations every day. These patient data can greatly benefit the health care organization if data mining techniques are applied upon these data sets. However, individual identifiable patient information needs to be protected in accordance with Health Insurance Portability and Accountability Act (HIPAA), and the quality of patient data also needs to be ensured in order for data mining tasks achieve accurate results. This thesis describes a patient data transformation system which transforms patient data into high quality and anonymous patient records that is …

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Longwall Weighting Events At Phalen Colliery, Nova Scotia, Canada, Robert J. Macdonald Dec 2000

Longwall Weighting Events At Phalen Colliery, Nova Scotia, Canada, Robert J. Macdonald

Graduate Theses, Dissertations, and Problem Reports (ETD)

Weightings are dynamic phenomenon observed in mines where coal is extracted using the longwall mining method. Weightings are characterized by high convergence rates within the powered supports which maintain roof stability along the longwall face. Rapid convergence is induced by ground pressures that exceed the load capacity of the supports, and forces them to yield. A weighting event need not necessarily impact the mining process negatively, but notable cases exist where weightings have caused extensive damage to roof strata resulting in large roof falls and prolonged periods of lost coal production.;This thesis describes the history of four longwall panels (No's …

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The Benton Harbor Area Benchmarking Study, George A. Erickcek, Brad R. Watts Dec 2000

The Benton Harbor Area Benchmarking Study, George A. Erickcek, Brad R. Watts

Reports

No abstract provided.

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Straight From The Heart, Volume 2, Number 4, Sacred Heart University Dec 2000

Straight From The Heart, Volume 2, Number 4, Sacred Heart University

News, Magazines and Reports

No abstract provided.

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Bs News Dec 2000

Bs News

Building Services Engineering

No abstract provided.

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