3,740 research outputs found

    Report of activities of the advanced coal extraction systems definition project, 1979 - 1980

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    During this period effort was devoted to: formulation of system performance goals in the areas of production cost, miner safety, miner health, environmental impact, and coal conservation, survey and in depth assessment of promising technology, and characterization of potential resource targets. Primary system performance goals are to achieve a return on incremental investment of 150% of the value required for a low risk capital improvement project and to reduce deaths and disability injuries per million man-hour by 50%. Although these performance goals were developed to be immediately applicable to the Central Appalachian coal resources, they were also designed to be readily adaptable to other coals by appending a geological description of the new resource. The work done on technology assessment was concerned with the performance of the slurry haulage system

    Synthesis of regional crust and upper-mantle structure from seismic and gravity data

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    Analyses of regional gravity and magnetic patterns, LANDSAT images and geological information revealed two major lineaments crossing western Pennsylvania and parts of surrounding states. These lineaments are inferred to be expressions of fracture zones which penetrare deeply into the crust and possibly the upper mantle. The extensions of the Tyron-Mt. Union and the Pittsburgh-Washington lineaments bound a distinct crustal block (Lake Erie-Maryland block) over 100 km wide and probably more than 600 km in length. Evidence exists for the lateral displacement of this block at least 60 km northwestward during late Precambrian to Lower Ordovician time. Subsequent movements have been mainly vertical with respect to neighboring blocks. A possible crustal block that passes through eastern Kentucky, proposed by a TVA study on tectonics in the southern Appalachians, was also investigated. Finally, the use of regional gravity and magnetic data in identifying major crustal structures beneath western Pennsylvania is discussed

    Overall requirements for an advanced underground coal extraction system

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    Underground mining systems suitable for coal seams expoitable in the year 2000 are examined with particular relevance to the resources of Central Appalachia. Requirements for such systems may be summarized as follows: (1) production cost; (2)miner safety; (3) miner health; (4) environmental impact; and (5) coal conservation. No significant trade offs between production cost and other performance indices were found

    Identity, Discourse, and Rehabilitation in Parole Hearings in the United States

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    Research on parole in the United States has primarily followed a deterministic approach, favoring an examination of variables contributing to release. However, a great deal of prior research neglects a central aspect of the parole process: mainly the hearing. Adopting an ethnographically informed conversation analytic approach, this article addresses one tactic offenders utilize to appeal to a state parole board for release– claiming rehabilitated status. Offenders appealing for parole attempt to establish, in a performative space, their identity as rehabilitated. More globally, this article addresses how individual manage, assert, and negotiate identity in the course of interaction. The achievement of “rehabilitation” is substantiated when it results in early release from prison

    Requirements for the conceptual design of advanced underground coal extraction systems

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    Conceptual design requirements are presented for underground coal mining systems having substantially improved performance in the areas of production cost and miner safety. Mandatory performance levels are also set for miner health, environmental impact, and coal recovery. In addition to mandatory design goals and constraints, a number of desirable system characteristics are identified which must be assessed in terms of their impact on production cost and their compatibility with other system elements. Although developed for the flat lying, moderately thick seams of Central Appalachia, these requirements are designed to be easily adaptable to other coals

    Synthesis of regional crust and upper-mantle structure from seismic and gravity data

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    Available seismic and ground based gravity data are combined to infer the three dimensional crust and upper mantle structure in selected regions. This synthesis and interpretation proceeds from large-scale average models suitable for early comparison with high-altitude satellite potential field data to more detailed delineation of structural boundaries and other variations that may be significant in natural resource assessment. Seismic and ground based gravity data are the primary focal point, but other relevant information (e.g. magnetic field, heat flow, Landsat imagery, geodetic leveling, and natural resources maps) is used to constrain the structure inferred and to assist in defining structural domains and boundaries. The seismic data consists of regional refraction lines, limited reflection coverage, surface wave dispersion, teleseismic P and S wave delay times, anelastic absorption, and regional seismicity patterns. The gravity data base consists of available point gravity determinations for the areas considered

    Resource targets for advanced underground coal extraction systems

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    Resource targets appropriate for federal sponsorship of research and development of advanced underground coal mining systems are identified. A comprehensive examination of conventional and unconventional coals with particular attention to exceptionally thin and thick seams, steeply dipping beds, and multiple seam geometry was made. The results indicate that the resource of primary importance is flat lying bituminous coal of moderate thickness, under moderate cover, and located within the lower 48 states. Resources of secondary importance are the flat lying multiple seams and thin seams (especially those in Appalachia). Steeply dipping coals, abandoned pillars, and exceptionally thick western coals may be important in some regions of subregions, but the limited tonnage available places them in a position of tertiary importance

    Choosing treatment for localised prostate cancer: A patient-conducted-interview study

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    Objectives: Treatment choice can be particularly difficult in localised prostate cancer because of the uncertainty involved. Indeed, some men prefer maintaining their masculine identity and quality of life to potentially securing longer-term survival through surgery or radiotherapy. UK health services are now obliged to leave the choice of treatment to the patient and the aim of this study is to improve understanding of patients’ experiences of choosing treatment. Methods: A one-day participative workshop where men of six months post-diagnosis design and conduct audio and video interviews on each other about their experiences of choosing treatment. Results: The findings show that treatment choice is a complex process combining emotional and rational elements. Information gathering and delegation to professional expertise were two key themes that emerged. Conclusions: The findings emphasise that treatment choice for localised prostate cancer is little like the traditional notions of consumerism from which it is derived. Importantly, the results illustrate, from a patient perspective, how health professionals can engage in their roles as information providers and as experts
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