Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

Graduate Theses, Dissertations, and Problem Reports (ETD)

Discipline
Keyword
Publication Year
File Type

Articles 6691 - 6720 of 7646

Full-Text Articles in Entire DC Network

Improving Commercial Vehicle Crash Data Quality In West Virginia, Kris Sean Gillespie Dec 2000

Improving Commercial Vehicle Crash Data Quality In West Virginia, Kris Sean Gillespie

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to identify methods to improve commercial carrier crash data in West Virginia including coal trucks. All organizations and agencies involved with commercial carrier safety need ready access to basic data describing the crash-involved operator, vehicle, and environment. Such data are necessary to any programmatic or engineering countermeasures. The basic approach used to accomplish the research objectives involved a series of regional meetings where law enforcement personnel expressed their opinions about ways to improve commercial vehicle crash data quality. These results were then weighted and prioritized. The top five solutions generated at these meetings were: …

Go to article

Assessing Computer -Mediated Communication Discourse Of A Traumatic Brain Injury Survivor, Cheryl L. Fickey Prichard Dec 2000

Assessing Computer -Mediated Communication Discourse Of A Traumatic Brain Injury Survivor, Cheryl L. Fickey Prichard

Graduate Theses, Dissertations, and Problem Reports (ETD)

Speech-language pathologists and audiologists have begun using computer technology for information storage and retrieval and as one means of providing clinical services to communication-disordered patients. The purpose of this study is to develop a protocol to assess the written communication of brain-injured clients whose communication therapy milieu includes interactions with the world outside the treatment room through computer-mediated communication (CMC).;A panel of experts reviewed a series of discourse analysis procedures and rated their perceptions of validity, reliability, and ease-of use for the procedures as means of evaluating CMC discourse. The Computer-Mediated Communication Evaluation Protocol (CMC-EP) was developed based on the …

Go to article

West Virginians' Perceptions And Use Of Complementary Medicine, Joshua David Blevins Dec 2000

West Virginians' Perceptions And Use Of Complementary Medicine, Joshua David Blevins

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to determine how West Virginian's perceive and use complementary medicine. The first objective was to determine the frequency of respondents who had used at least one complementary therapy in the last year. The second objective was to determine the most commonly used complementary therapies among respondents. The third objective was to examine the demographic characteristics of respondents who used complementary therapies. The fourth objective was to determine if certain types of medical problems led to complementary medicine use among respondents. The fifth objective was to show the percentage of users who informed their physician …

Go to article

Evaluation Of Maternal Serum Triple Screen As An Identifier Of Trisomy 21 Pregnancy, Jonnie Ann Lane Dec 2000

Evaluation Of Maternal Serum Triple Screen As An Identifier Of Trisomy 21 Pregnancy, Jonnie Ann Lane

Graduate Theses, Dissertations, and Problem Reports (ETD)

Maternal serum triple screen is used to identify women less than 35 years of age who are at an increased risk of having a fetus with Down syndrome. The screen identifies 5% of women tested as being at an increased risk but only 2--3% of these women actually have a fetus with chromosome abnormalities, indicating a high false positive rate. Medical records for 900 cases referred for maternal serum triple screen and maternal age were reviewed. The percentages of abnormal karyotypes in the two populations were not significantly different from each other or the expected value. While 3% of all …

Go to article

Synthesis And Characterization Of Metal Oxide Nanoparticles, Heidi Jo Magnone Dec 2000

Synthesis And Characterization Of Metal Oxide Nanoparticles, Heidi Jo Magnone

Graduate Theses, Dissertations, and Problem Reports (ETD)

Nanoparticles of CuO, Co3O4 and Mn5O 8 were prepared via sol-gel chemical routes. Thermal treatments of the gels were used to obtain particles of different sizes, as determined by the widths of the Bragg lines in x-ray diffraction. To prepare CuO nanoparticles, a Cu(OH)2 gel was first produced by reacting copper nitrate with sodium hydroxide, followed by annealing the gel at temperatures between 160°C to 1,000°C to produce particles in the 6 to 36 nm range. Nanoparticles of Co3O4 in the size range of 9 to 45 nm were prepared in an analogous manner by reacting cobalt nitrate and sodium …

Go to article

Mapping Appalachia, Jennifer Hall Boggess Dec 2000

Mapping Appalachia, Jennifer Hall Boggess

Graduate Theses, Dissertations, and Problem Reports (ETD)

The complexities of natural and human events that make up the history of a place also create components of its image. Images, even those that are meant to describe limited, specific information, often reveal more than that which they were designed to tell. The maps that have been used in conjunction with traditional notions of landscape painting suggest that there is no single way to understand a place. They also hint of something ineffable but true emerging from their forms. The history of movement of people and natural forces, the arriving and leaving of individuals and cultures change the landscape. …

Go to article

Commercialism, Subsistence, And Competency On The Western Virginia Frontier, 1765--1800, John M. Boback Dec 2000

Commercialism, Subsistence, And Competency On The Western Virginia Frontier, 1765--1800, John M. Boback

Graduate Theses, Dissertations, and Problem Reports (ETD)

Since the early nineteenth century, Americans have frequently associated the pioneers of the Appalachian Mountains with subsistence farming, economic independence, and a certain degree of hostility toward capitalism. This thesis disproves the myth of pioneer self-sufficiency by demonstrating how the men and women who settled in western Virginia during the final third of the eighteenth century used a variety of tactics in their struggle to achieve a competency. Although subsistence activities, such as hunting and farming, undoubtedly held an important place in the backcountry domestic economy, the settlers also interacted with the commercial market as both producers and consumers of …

Go to article

Effects Of Gender And Gender Role On Cardiovascular Reactivity And Anger Experience During An Interpersonal Interaction, Andria Leigh Black Dec 2000

Effects Of Gender And Gender Role On Cardiovascular Reactivity And Anger Experience During An Interpersonal Interaction, Andria Leigh Black

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study examined gender and gender role differences in cardiovascular reactivity and anger experience during an interpersonal interaction. Ninety-six participants interacted in dyads (traditional masculine men with traditional feminine women, and androgynous men with androgynous women). Agency (degree of challenge; High versus Low) and Communion (degree of agreement; Agree versus Disagree) were manipulated. Heart rate (HR) and systolic and diastolic blood pressure (SBP and DBP) were assessed. Participants completed questionnaires assessing state and trait anger, and angry thoughts. Traditional women exhibited higher HR during speaking and listening intervals than other groups. Higher levels of state anger were reported for individuals …

Go to article

Effects Of Pain And Fear Stimulus Intensity Levels On Pain Responding In Chronic Pain Patients, John Thomas Sorrell Dec 2000

Effects Of Pain And Fear Stimulus Intensity Levels On Pain Responding In Chronic Pain Patients, John Thomas Sorrell

Graduate Theses, Dissertations, and Problem Reports (ETD)

Fear has been found to increase and decrease pain responding in various contexts, and the effects of fear and pain stimulus intensity levels on pain responding have not been examined. Forty chronic pain patients were exposed to an algometer pressure pain device which stimulated different fingers; there were two levels of pressure pain (i.e., high and low). Also, there were two levels of induced fear (i.e., high and low). Significant main effects of pain stimulus intensity level were found on threshold pain time, tolerance pain time, and self-reports of fear and pain. Also, a significant main effect of gender was …

Go to article

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.

Go to article

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 …

Go to article

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 …

Go to article

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 …

Go to article

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 …

Go to article

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 …

Go to article

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. …

Go to article

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 …

Go to article

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 …

Go to article

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 …

Go to article

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. …

Go to article

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 …

Go to article

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 …

Go to article

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 …

Go to article

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 …

Go to article

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 …

Go to article

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 …

Go to article

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. …

Go to article

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 …

Go to article

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 …

Go to article

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 …

Go to article

First Prev Next Last