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Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 5, pp. 3-20, September-October, 1991.  相似文献   
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An analysis and estimate are performed for possible schemes of spatial distribution of gas-dynamic phenomena in potash deposits by the methods of mathematical statistics. The problem stated is solved by comparing the numerical characteristics of the events observed and those obtained on the basis of the theoretical model developed.  相似文献   
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In November 2000 the Belgian stainless steel producer UGINE & ALZ Belgium nv, a company of the Arcelor Group, awarded VAI a contract for the upgrading and expansion of their steelmaking plant. The overall project included the revamping and supply of new equipment and systems for the steelmaking, continuous casting and environmental protection facilities. An essential part of this ambitious modernization program was the upgrading and expansion of the existing single-strand slab caster, with an output of 600 000 t/a, to a combined single- or twin-strand slab caster with a nominal production capacity of 1.2 million tons — the world’s largest stainless steel slab caster. All upgrading and installation activities had to be carried out within an extremely tight caster shut-down period of 21 days only in order to minimize production losses. This paper discusses the innovative project management solutions implemented in combination with extensive preassembly activities and workshop testing to assure the successful outcome of this project.  相似文献   
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The study outlines the effects of surface and underground subsidence patterns on the spatial distribution of in-situ permeability and its effects on groundwater inflow. The behaviour of strata surrounding a longwall face where limited knowledge exists has been outlined. The effects of mining subsidence on the surface flow pattern have been described with the remedial solutions. The mechanism of formation of sinkholes in certain chemical rockmass has been described. Factors affecting mine water inflow have been described in detail with the aid of a simplified conceptual model and case studies. Practical examples of undersea workings and those under a large accumulation of water are given, both in the United Kingdom and worldwide.  相似文献   
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Isolated headwater streams in mined watersheds may have good water quality and fish habitat, yet be disconnected from immigration sources by stream segments impaired by acid mine drainage (AMD). Studies of fish and macroinvertebrate communities, habitat, and a number of hydrochemical parameters in Monday Creek, Ohio, show that AMD eliminates fish communities and severely limits macroinvertebrate communities in directly affected tributaries. Isolated headwaters in the heavily mined Monday Creek watershed have relatively good water quality and habitat, but poor fish communities. Comparison of isolated Monday Creek headwaters with non-isolated reaches in unmined watersheds indicates that differences in fish communities are attributable to isolation. Fish communities in isolated headwaters have lower Indices of Biotic Integrity (IBI) than comparable non-isolated communities, reduced species numbers, and lower numbers of individuals, despite suitable habitat as measured by the Qualitative Habitat Evaluation Index (QHEI). Comparison of macroinvertebrate communities shows higher Invertebrate Community Indices (ICI), and no apparent species loss, which can be attributed to the obligate flight stage in the life cycle of many macroinvertebrates, which enables them to overcome aquatic barriers. The implication of this research is that there is an opportunity for recovery of depleted fish communities in large AMD-isolated areas with good water quality, suitable habitat, and intact macroinvertebrate communities, by downstream treatment or source control of AMD to create aquatic corridors for fish immigration.  相似文献   
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