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Number of results: 10
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Abstract

226 papers by Polish authors and co-authors have been collected. They deal with Antarctic or sub-Antarctic fishes and also their parasites. The majority (35.7%) of the publications discuss fish biology including growth, age, maturity, feeding and occurrence of particular species in the area. Fewer papers are devoted to parasitology (26.0%). Papers dealing with fish biomass and exploitation make up 18.5%. Papers dealing with morphology and systematics make up 6.6%. The remaining papers are devoted to technology, physiology, palaeontology and others.
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Abstract

The contemporary underground mining of raw minerals is more and more associated with geological and mining software packages which support the work of designers from the moment of the exploration of a deposit, determination of its size and quality, geological, hydrogeological and tectonic conditions, by planning the development and cutting of the deposit. Production planning is one of the most important activities carried out in the course of a mining project, because it allows to set specific production results of a mine in relation to a time unit, and then allows for a verification of the degree of completion of the assumed plan. At present, computer-aided design is applicable to daily or long-term output planning taking deposit, qualitative, quantitative and cost constraints into account. In the article, selected forms of ore deposits were presented. On the basis of several dozen boreholes up to 300m in length, an exemplary fragment of the ore cutting model using computer-aided design of mining works was presented. By using modern computer software - ABB MineScape with modular construction, the possibilities of improving the process of development of future exploitation areas have been determined. In particular, the arrangement of boreholes, based on which ones the cross sections were made with, present the exemplary lithostratigraphic thickness of layers, including the location of discontinuous deformations in the form of faults, and an ore bearing zone. For the block model, resources with priority for metal N o. 1 and 2 were calculated. I n the last section of the article, the cutting idea for a shallow ore deposit has been presented. The degree of effective use of the deposit has been analysed for the room and pillar mining method.
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Abstract

This article concerns numerical modeling of the impact of mining operations on fault behavior, carried out on the basis of a calculation program based on the finite element method. It was assumed that the fault is a single discontinuity in the form of a vertically-oriented plane, and the conditions in which surfaces merge are defined by the right of the Coulomb friction. On the one hand, the calculations are related to the fault’s response to additional weight resulting from mining operations, and on the other, they are related to the impact that occurrences in the fault’s plane had on the immediate surroundings of the extraction center. The behavior of the fault was analyzed based on distributions in the plane of shear stress and slip, together with their range and energy dissipated due to friction. In turn, the impact of the fault on its immediate environment was analyzed based on variations in the total energy density of elasticity. The results of numerical modeling made it possible to draw conclusions concerning mining operation in the proximity of tectonic dislocations in the context of seismic hazard’s levels.
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Abstract

The paper presents a model for calculations of the temperature field in electric mine motors with a water cooled frame. That model was worked out with use of modified and improved thermal networks developed by the author for determining the temperature distributions in different types of ac machines. Thermal calculations for a selected type of 400 kW mining motor were performed with use of an original computer program. Their results were compared with those obtained from measurements. On the basis of the verified simulation results there was determined the influence of value changes of parameters characterising the work environment condition (ambient temperature, inlet temperature and cooling water discharge, degree of covering the casing with coal dust) on the mining motor thermal state.
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Abstract

The author believes that one all-inclusive assessment of Marx’s philosophy is inevitably misleading. Although Marx constructed one theory that has a texture of a uniform fabric, the fabric has been woven with threads of two very different qualities. His presentation of capitalist instability, exploitation and alienation has the quality of scientific explanations. But his treatment of dialectic, economy formulated in terms of priceless commodities and his vision of communism is fantastic and arbitrary.
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Abstract

The paper presents the experience of using the ŁPrP, ŁPKO, ŁPSp, ŁPSpA i ŁPSp3R types of flattened supports for longwall entries in the conditions of the JSW S.A. Knurów-Szczygłowice coal mine. The article concentrates on the support solutions applied in the conditions of the mine and the results in terms of stability and usefulness of the structures of the supports. An analysis of the load bearing capacity and technological conditions has been conducted for various flattened supports solutions, with special consideration given to the ŁPSp and ŁPrPJ support sets. Comparing these two, the ŁPSp exhibits a load bearing capacity that is 21% higher while using 31% less steel mass. The experiment results allowed to determine that the ŁPSpA and ŁPSp3R support types are an advantageous solutions in case of longwall set-up rooms.
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Abstract

The demand for REE was the background to include them to those consisting of the property of the State Treasury in Poland, enumerated in the Geological and Mining Law (Article 10). The PLN 500/kg REE payment for exploitation of REE (exploitation tax) was introduced. Both proposals will restrain the REE recovery from exploited domestic mineral commodities. The term REE is imprecise. Their deposits are rare and may be classified as “REE ore deposits”. The REE are often the accompanying constituents in varied mineral commodities and are recoverable during their processing, outside the mine. The application of an exploitation tax in such a case is inapplicable. The established value of the exploitation tax is incomparably high in respect to the value of the REE contained in mined mineral commodities. The analysis of introduced changes of mining and geological law allow to suggest the reevaluation of ownership based subdivision of mineral commodities: name the mineral commodities belonging to the land property owners and leave the list of mineral commodities consisting property of the State Treasury open. The more careful approach is also necessary in the formulation of Geological and Mining Law. It should be preliminary formulated by persons competent in geology and mining and subsequently adjusted to juridical exigencies.
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Abstract

The continental shelf beyond 200 nautical miles (NM) accounts for a great value for States. The development of technologies and science has allowed the human economic and scientific activities on the deep parts of the ocean floor. The continental shelf is rich with living resources. The living resources of continental shelf are also valuable, since they possess valuable genetic resources for pharmaceuticals and commercial products. Many valuable non-living resources are situated on the continental shelf, including hydrocarbons (oil and gas) and minerals (e.g. manganese, nickel, cobalt, gold, diamonds, copper, tin, titanium, iron, chromium and galena). Therefore, States have spent significant resources on conducting a research and exploring their continental shelf and the Commission on the Limits of the Continental Shelf (CLCS) has received seventy-seven submissions and issued twenty-nine recommendations pursuant to Article 76 (8) of the United Nations Convention on the Law of the Sea (UNCLOS). With the expected improvement of technological capabilities in decades to come, especially, in deep waters, the continental shelf will be explored more thoroughly and perhaps will meet no technological limits.
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Abstract

Caving in the excavation of mining galleries is a dangerous phenomenon, resulting in a threat to the health and life of humans, technological difficulties (transport, ventilation, etc.) and economic losses. Mining galleries list: design errors, runtime errors, errors and random causes among the causes of the caving occurring in recent periods in the excavation of underground coal mines. Examples in the recent period of caving in the excavation of mining galleries in coal mines indicated that one of the main causes of the situation was the loss of capacity and double timber technical wear caused by the corrosion of the profile. In practice, the caving that occur as a result of the technical wear can be divided into the breaking arc of a roof – bar, the loss of stability of one of the heading walls and a total heading collapse. On the basis of the carried out analysis of these cases, guidelines were proposed for improving the safe operation of the workings. The improvement of support stability may be achieved by applying additional supports, stabilizing the structure by bolting the support sets or by introducing a fiber-reinforced concrete coating with injection into the rock mass. Examples of caving occurring in the excavation, for which the preparatory selection of support does not match the geological-mining conditions, were also presented. The summary indicated the importance of diagnostics roadway in the safe and efficient conduct of mining that should be covered by the operational rules, and their scope and frequency should be adapted to the rank of the occurrence of hazard and support construction.
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Abstract

The events that took place on April 10,2010 on the Gulf of Mexico began an international debate on minimizing and materializing the risk of dangerous occurrences and accidents during the exploitation of offshore energy resources. In the aftermath of this event to ensure safe operation in European maritime areas, the European Union decided to introduce regulations throughout the entire EU. On June 12, 2013, Directive 2013/30/EU of the European Parliament and of the Council on safety of offshore oil and gas operations and amending Directive 2004/35/EC was issued. The main aim of the Directive is to reduce the occurrence of major accidents relating to offshore oil and gas operations and limits their consequences. The article is a review of provision of Directive 2013/30/UE with particular regard to requirements at the national level. What is more, the paper indicates solutions which must be introduced by July 19, 2018 in offshore companies. The incorporated solutions must include the protection of the marine environment against pollutions (especially oil spills), establish minimum conditions for safe offshore exploration and the production of oil and gas and improve the response mechanism in the eventof an accident. The paper also presents accidents which take place in oil and gas fields which are a background of necessary improvements of safety during offshore operations.
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