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Number of results: 97
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Abstract

The coal exploitation in the Upper Silesia region (along the Vistula River) triggers the strata seismic activity, characterized by very high energy, which can create mining damage of the surface objects, without any noticeable damages in the underground mining structures. It is assumed that the appearance of the high energy seismic events is the result of faults’ activation in the vicinity of the mining excavation. This paper presents the analysis of a case study of one coal mine, where during exploitation of the longwall panel no. 729, the high energy seismic events occurred in the faulty neighborhood. The authors had analyzed the cause of the presented seismic events, described the methods of energy decreasing and applied methods of prevention in the selected mining region. The analysis concluded that the cause of the high energy seismic events, during the exploitation of the longwall panel no. 729 was the rapid displacements on the fault surface. The fault’s movements arose in the overburden, about 250 m above the excavated longwall panel, and they were strictly connected to the cracking of the thick sandstone layer.
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Abstract

In order to fully adapt to market requirements, mining enterprises in recent years have implemented standardized systems for quality, safety and health at work and environmental management. The standards for individual systems define the requirements of applying specific procedures and actions to implement the adopted policy aimed at achieving the assumed goals. The combination of business procedures and practices is more effective in the case of their integration than the activities carried out under separate systems. They then function under the name of an integrated management system (IMS). Properly implemented IMSs most often contributes to a more harmonious functioning of the enterprise and the elimination of recurring activities in the areas concerning individual systems, and thus to the optimization of costs related to their implementation and maintenance. Improving the operational efficiency of the mining enterprise and mines included in it, while maintaining the requirements of work safety and environmental protection. In the conditions of a market economy, improving the efficiency of functioning and providing sources of business financing is a key necefity for mining enterprise (Bąk 2007, 2008). Mines need to be properly managed to survive. The key problem is the design and implementation of an efficient management system and its continuous improvement based on the adequacy of system solutions. This is an answer to the question whether the management system of a mining enterprise (mine) corresponds to its real needs in the process of achieving objectives. Improvement of management systems must be based on an appropriate diagnosis. The aim of the article is to present the original solution, which is a tool for improving the integrated management system in Polish mining enterprises.
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Abstract

The paper presents differences between technical states and technical operation states of haul trucks in the technical operation process. The specification and analysis of operational parameters of technological vehicles used in surface mining is possible only due to more and more frequently used diagnostic – telemetric systems. While a detailed analysis of machines operation data can result in the more effective management of mining plant operations and the mining process itself. The determination of operational state indices and their individual components allows preventive actions to be commenced, resulting in improving the work organization of the entire mine machinery system. Moreover, the future technical state of machines operated in surface mining is strictly related to the current state and also depends on the events that occurred in the extraction system. A set of parameter values of individual state characteristics, which allow the haul trucks technical and operational state to be characterized, is a direct effect of a telemetric – diagnostic system operation.
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Abstract

The extraction of mineral deposits is usually charged with additional taxes or royalty fees that go beyond the general income tax. As a rule, countries prefer stable sources of fiscal revenues based on the volume of raw material extraction, and investors prefer models based on profit tax, i.e. taking operating costs and risks lower than the expected profitability of the project into account. As a rule, too high a burden for the mining sector affects investors’ decisions regarding the introduction of new investments. There are a number of examples where excessive fiscal burdens force investors to move to countries with more favorable tax systems. An analysis of various forms of taxation of mining enterprises around the world has been presented and compared with the system implemented in Poland. Usually, the countries that apply the royalty fee in the mining sector at the same time introduce a number of adaptation mechanisms. This is crucial for new investments due to the fact that they may to some extent compensate for the high costs of transition from the investment to the operational phase. In most cases, several incentive mechanisms are used at the same time, e.g. the accelerated settlement of investment expenditures and the unlimited settlement of losses. The copper and silver mining tax introduced in Poland increased the discounted effective tax rate (ETR) from 38.5% to 89% for the entire investment period, which resulted in a 11-year return on investment, as well as a drop in the internal rate of return (IRR).There are currently no mechanisms in Poland which would balance the burden of this tax for a new investor. In order to balance the extraction tax for certain minerals in terms of the IRR and ETR key indicators, the introduction of several adaptation mechanisms has been proposed. For new investments the most essential mechanism is the preferential settlement of capital expenditures incurred in the pre-production phase of an investment. The others include accelerated amortization, the ability to deduct certain expenses for the exploration phase from the tax base, along with an extended tax loss settlement period, or a mechanism for deducting a certain percentage of investment expenses directly from the tax.
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Abstract

Underground mining extraction causes the displacement and changes of stress fields in the surrounding rock mass. The determination of the changes is extremely important when the mining activity takes place in the proximity of post-flotation tailing ponds, which may affect the stability of the tailing dams. The deterministic modeling based on principles of continuum mechanics with the use of numerical methods, e.g. finite element method (FEM) should be used in all problems of predicting rock mass displacements and changes of stress field, particularly in cases of complex geology and complex mining methods. The accuracy of FEM solutions depends mainly on the quality of geomechanical parameters of the geological strata. The parameters, e.g. young modulus of elasticity, may require verification through a comparison with measured surface deformations using geodetic methods. This paper presents application of FEM in predicting effects of underground mining on the surface displacements in the area of the KGHM safety pillar of the tailing pond of the OUOW Żelazny Most. The area has been affected by room and pillar mining with roof bending in the years 2008-2016 and will be further exposed to room-and-pillar extraction with hydraulic filling in the years 2017–2019.
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Abstract

Mineral deposits are such type of assets, the valuation of which can be carried out in a very diverse manner. Methods and procedures for such a valuation are most often applied to mineral deposits with mineral reserves (according to the CRIRSCO classification), much less frequently and usually only using a comparative approach for undeveloped, initially recognized mineral deposits (with mineral resources). In Poland, a significant portion of mineral deposits, mainly of energy, metal and chemical minerals, are covered by the so-called mining property of the Treasury. At the moment, there is a lack of consistent and thoughtful management of these deposits. The appropriate methodology for valuing these deposits, which are at various stages of recognition (sometimes also of development), should be one of the key elements of such management. The State Treasury usually disposes of mining rights by “establishing” mining usufruct in the form of a contract, with the determination of remuneration for this establishment. The rules for determining remuneration for the establishment of mining usufruct are determined on the basis of an internal informal document of the Ministry of the Environment with very simplified rules for determining this remuneration, to a very limited extent related to the actual value of the deposit, which is also variable over time. This fee should be in close relation to the value of the mineral deposit valued at a given moment, taking the current conditions, including technological, environmental, formal and legal, and – in particular – market conditions into account. The valuation of mineral deposits covered by mining property, except for current needs in determining the basis for remuneration for mining usufruct establishing, should also be used to determine the value of these deposits annually as part of the State Treasury property and to present its results as part of the State Treasury Property Status Report. It is an open matter whether the methodology of valuation of the discussed mineral deposits should be based on accepted and widely used solutions for the valuation of mineral deposits for the purposes of business transactions or based on methodology of valuation of deposits as part of the planned system of Integrated Environmental and Economic National Account (up to date poorly developed). The paper presents the most important elements of both methodological approaches. It seems that the use of selected elements of each of these approaches would be advisable in this case.
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Abstract

The research of development capabilities is a fundamental of strategic issues, which has to be taken into consideration by coal mines. This is particularly difficult in the current environment, which is determined by its crisis situation. In such conditions, it is necessary to take difficult decisions, and serious, strategic challenges into account, which allow for the crisis to be overcome, for the renewal and economic effectiveness of the operation of these coal mines, which have potential to grow, and closing the coal mines, which have not potential to grow. Due to the effects of such decisions, which concern not only coal mines but also the Silesian region, it is essential to prepare information to support them and promote rational choices. This is related to the issue of research for development possibilities. The article presents considerations related to the subject of research for development possibilities of coal mines in a crisis situation. Taking the results of literature study into account, the model of research process was developed, and identified the research issues concerning the following: - the identification of external factors which determine the possibility of development of the Polish mines and drawing a schedule of their changes in the future, - the identification of internal factors which determine the possibility of development of the Polish mines, - developing a way for the assessment of the development potential of the coal mines, to show appropriate strategic options and action programmes for these options, - determining possible strategic options and corresponding schedules, appropriate for the specific nature of the mines. The proposition of their solutions, which were obtained in the process of using the specific methods and research tools, allowed the guidelines in terms of research of development capabilities of coal mines to be presented.
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Abstract

A lot of interest has recently been put into the so-called ‘virtual cryptographic currencies’, commonly known as cryptocurrencies, along with its surrounding market. The blockchain technology that stands behind them is also becoming increasingly popular. From the perspective of maintaining energy security, an important issue is the process of mining individual cryptocurrencies, which is associated with very high energy consumption. This operation is usually related to the approval of new blocks in the blockchain network and attaching them to the chain. This process is carried out through performing complex mathematical operations by various devices, which in turn require high power and respectively consume a lot of energy. The impact of cryptocurrency miners on the power and energy demand level might gradually increase over time, therefore this issue shouldn’t be ignored. Comparing the above information in parallel with the growing need for providing demand side response (DSR) services in the Polish Power System, raises the question whether devices used for mining cryptocurrencies can be used for the purpose of balancing the power system. This paper presents an analysis of the possibility to provide the demand side response services by groups of cryptocurrency miners users. The analysis was carried out taking basic functional, technological and economical aspects of these devices’ operations into account.
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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 article presents research on the relationship between mining and used resources on the example of Gliśno gravel pit. As regards to resources, the following issues were analyzed: employees’ working time, time of running machines, fuel consumption and electricity consumption. The aim of the publication is to examine the dependencies that exist between the analyzed variables. KPI’s (Key Performance Indicators) were calculated for individual resources. The analysis presented in the publication contains data from 2008-2014.
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Abstract

This article deals with a group of Polish surnames motivated by lexis from the field of salt mining. The analysed surnames are excerpted from “Słownik nazwisk współcześnie w Polsce używanych”, edited by Kazimierz Rymut, as well as from other onomastic compilations. These anthroponyms vary in terms of their origins and linguistic construction. We can distinguish from among these anthroponyms: 1) surnames motivated by impersonal nouns: solanka, solnica, sól, tołpa, żupa; 2) surnames motivated by adjectives: słony, solny; 3) surnames motivated by personal nouns: prasoł, solarz, solnik, warzyc, warzysz, żupnik. The description of particular ‛salt’ surnames, apart from their frequency, includes their geographical distribution, which only in some cases is connected with the location of old salt mines, found mainly in the Lesser Poland (Małopolska).
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Abstract

The post-mining areas due to the difficulties of those, often associated with expensive activities, usually take the form of wasteland. In contrast, unavailable, unused and alien areas the mentality of residents, are identified with empty space. The purpose of the authors was to answer the question: Are post-mining areas becoming empty spaces? Her research basis was changes in the functioning of post-mining areas and empty spaces in Katowice – a city with a long-standing mining tradition. Using GIS tools, a spatial analysis was carried out to determine the empty spaces functions and the perceiving of the post-mining areas by residents or users of a given district nearby.
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Abstract

Post-industrial areas are an area of concentration, penetration and shaping the economic, social and environmental zone. The strategic goal of transforming post-industrial areas should be to obtain a new, dynamic and favorable state of equilibrium for a given area, as well as its surroundings after cessation of operations. The purpose of the article is to indicate the possibility of adaptation of post-industrial areas, especially after exploitation of the mineral, to perform new functions. The direction and the purpose of the recultivation and planning actions to a large extent may be influenced by specific social and economic conditions affecting the competitiveness of each and individually treated fragment of space.
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Abstract

The economic envelopes obtained by optimization techniques in open pit mining are transformed into operational phases that are suitable for extraction through ramp designs. This process is performed with the aid of specialized design software, which is still very manual, time consuming and highly dependent on the expertise of the planner. In this paper, we introduce a new methodology based on a mathematical model to automatically propose the design of ramps from the economic envelope of a pushback, with the resulting envelope having the maximum value. The developed model was tested against a real case scenario showing reasonable and useable solutions for the planner. Using this approach, a planner can evaluate several alternatives in a reasonable time before selecting the final design.
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Abstract

The role of the hard coal mining sector in ensuring energy security of the country has been presented in the paper. An analysis of its current status was made based on the results obtained by the sector in 2017. Moreover, the determinants which are the precondition for further sustainable and efficient operation in the years to come have been defined.
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Abstract

The article describes mine survey works during opening old St. Anthony of Padua water adit in Horní Město (Czech Republic) to make it accessible to visitors. The works cover the connecting survey and orientation measurement, traverse measurement of the first opened part, setting-out projection of the end of opened part to the surface to make shaft from the surface, new connecting survey and orientation measurement by shaft and traverse measurement of the rest of water adit. Non-standard aids and techniques were used during surveying. One of the tools is a suspended prism holder developed at Institute of geodesy and mine surveying, VSB – Technical university of Ostrava, registered as a utility patent.
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Abstract

Planning in a mining enterprise is a complex and multifaceted action. For this reason, it is necessary to provide its proper organisation and adjust it to the specific conditions of conducting underground mining extraction. The prepared plans must make up a cohesive internal system, unambiguously determining the manner, range and safety requirements of the conducted extraction. In the most general manner, the various types of plans developed by organisational units of mining enterprises can be divided based on the timeframe, type, scope and object of planning. These are strategic plans, tactical plans and subject-based plans. The aim of the article is to present the issue of production planning in a mining enterprise and for the preparation of such a plan, first and foremost, information about, among other things, applicable legal regulations, market conditions and the specificity of a mining enterprise are necessary. Underground extraction of black coal deposits must be conducted while respecting the rules of sustainable development which satisfies current needs, without compromising the ability to satisfy the needs of future generations. Due to the specific nature of mining production, manifested, among other things, by such features as the diversity of conditions for conducting the activity, resulting from the changing geological-mining conditions of the deposit, low flexibility of the production process, associated with the impossibility to conduct alternative production and a very long-lasting investment process, planning the course and magnitude of production in a mining enterprise must proceed with the highest possible diligence. One should take into account a wide range of presented environmental, organisational and technical conditions, deciding about the safety and correctness of the course of the assumed production activities. However, in order to make them economically feasible and produce satisfying results in that regard, it is also necessary to analyse them carefully with respect to financial outcomes
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Abstract

The quarrying industry is changing the local landscape, forming deep open pits and spoil heaps in close proximity to them, especially lignite mines. The impact can include toxic soil material (low pH, heavy metals, oxidations etc.) which is the basis for further reclamation and afforestation. Forests that stand on spoil heaps have very different growth conditions because of the relief (slope, aspect, wind and rainfall shadows, supply of solar energy, etc.) and type of soil that is deposited. Airborne laser scanning (ALS) technology deliver point clouds (XYZ) and derivatives as raster height models (DTM, DSM, nDSM=CHM) which allow the reception of selected 2D and 3D forest parameters (e.g. height, base of the crown, cover, density, volume, biomass, etc). The automation of ALS point cloud processing and integrating the results into GIS helps forest managers to take appropriate decisions on silvicultural treatments in areas with failed plantations (toxic soil, droughts on south-facing slopes; landslides, etc.) or as regular maintenance. The ISOK country-wide project ongoing in Poland will soon deliver ALS point cloud data which can be successfully used for the monitoring and management of many thousands of hectares of destroyed post-industrial areas which according to the law, have to be afforested and transferred back to the State Forest.
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Abstract

An analysis of the impact of mining with caving on the surface shows that a type of rock mass strata seems to be one of the critical factors affecting the process. Correlating the values of mining-induced surface deformation with the rock mass structure and the state of its disturbance is of crucial importance. Therefore, if other mining conditions are left unaffected, then those factors exert the key influence on a course and distribution of subsidence and rock mass deformation. A proper description of rock mass type and properties also seems rational for a proper determination of prediction parameters, especially in the case of a multi-seam coal mining, and/or the exploitation carried out at considerable depths. A general outcome of the study discussed in this paper is the development of the methodology and model practices for determining the rock mass type and, as a result, for selecting the optimal values of parameters for predicting the values of surface subsidence in relation to particular geological and mining conditions. The study proves that the type of rock mass may be described by such factors as the influence of overburden strata, the influence of Carboniferous layers, the disturbance of rock mass and the depth of exploitation.
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Abstract

Recalling the body of experience gathered in the collieries of the Upper Silesian Coal Basin, the increased risk of seismicity and rockburst occurrences in confined conditions including the exploitation of remnants were identified. This study investigates geomechanical aspects of longwall mining in the areas affected by old excavations aimed at relaxation of a multi-bed deposits within a thick coal seam or a group of seams. It is assumed that high-energy seismicity is another factor determining the rockburst hazard alongside the state of stress. A case study is recalled, describing a colliery where mining-induced seismic activity of a de-stressed coal seam remained at the level comparable to or higher than it was experienced in the de-stressed seam operations. An analytical model was used to study the stress state and potential loss of structural continuity of an undisturbed rock body surrounding the longwall panel being mined beneath or over the abandoned workings. Recalling the developed model of the system involving nonlinear functions demonstrating the existence of abandoned mine workings within the rock strata, computer simulations were performed to evaluate the rockburst hazards along the face area. Discussions of results are based on observations of immediate roof convergence and the vertical stress concentration factor at the longwall face zone. Computational data of the modelled mining situations demonstrates that despite using the de-stressing method of mining, the occurrence of events impacting on mine working beneath and over abandoned workings cannot be precluded. Here the scale of rockburst hazards is determined by local mining and geological conditions, such as the type and extent of abandoned workings, their age and vertical distance between them and the coal seam currently mined.
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Abstract

The research aimed to establish tyre-road noise models by using a Data Mining approach that allowed to build a predictive model and assess the importance of the tested input variables. The data modelling took into account three learning algorithms and three metrics to define the best predictive model. The variables tested included basic properties of pavement surfaces, macrotexture, megatexture, and unevenness and, for the first time, damping. Also, the importance of those variables was measured by using a sensitivity analysis procedure. Two types of models were set: one with basic variables and another with complex variables, such as megatexture and damping, all as a function of vehicles speed. More detailed models were additionally set by the speed level. As a result, several models with very good tyre-road noise predictive capacity were achieved. The most relevant variables were Speed, Temperature, Aggregate size, Mean Profile Depth, and Damping, which had the highest importance, even though influenced by speed. Megatexture and IRI had the lowest importance. The applicability of the models developed in this work is relevant for trucks tyre-noise prediction, represented by the AVON V 4 test tyre, at the early stage of road pavements use. Therefore, the obtained models are highly useful for the design of pavements and for noise prediction by road authorities and contractors.
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Abstract

The aim of the article is to present the selected results of analytical investigations concerning possible directions of reducing the unit production costs in the mining company together with some results of practical calculations. The investigations emphasize the role of the rate of utilising the production capacity leading to reducing the unit production costs. The main component having an essential influence on the unit production costs are the fixed unit costs. Two basic indices of a crucial meaning for searching for possibilities leading to decreasing the unit production costs are assumed. The first index (w1) is a measure of the rate of utilising the production capacity, the second one (w2) concerns the fixed costs coincided with the unit of the production capacity. Theoretical considerations concerning the mathematical modelling of the unit production costs as the values depending on the rate of utilising the production capacity and the fixed costs coincided with the production capacity unit, are presented in the first part of the paper. The rationalisation criteria of the mine unit production costs are formulated. These criteria can constitute the elements of restructuring program for the mining company. The calculation example with the use of the practical input data shows the impact of the rate of utilising the production capacity on the mine unit production costs. In the example two variants of annual working time are taken into account. Results of appropriate calculations are presented and analysed in an aspect of reducing unit costs of production as a result of increasing rate of utilising the mine production capacity.
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Abstract

In the Carboniferous rock mass of the Upper Silesian Coal Basin, large changes in the geomechanical conditions often occur over relatively short distances. These conditions relate to rock properties that are primarily responsible for the occurrence of geodynamic phenomena in the rock mass. The main factor influencing the manifestation of these phenomena is tectonic stress developed during Variscan and subsequent Alpine orogenesis. This stress contributed to creating tectonic structures in the Carboniferous formations and influenced the properties of the rocks themselves and the rock mass they form. As a result of the action of the stresses, compaction zones (main stresses were compressive) were formed, along with zones in which one of the main stresses was tensile. For the compaction zones in the Carboniferous rocks, the following geomechanical parameters have been calculated: uniaxial compressive strength, Young’s modulus and post-critical modulus. The local stress field was determined according to the focal mechanism in selected areas (Main and Bytom troughs) to characterize changes in geomechanical properties of the rocks that are responsible for high-energy tremors (E ≥ 106 J, ML ≥ 2.2).
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Abstract

Open pit mining of rock minerals and the affected areas requiring further development are a serious challenge for shaping the positive image of the mining industry among the public. The direction and method of post-mining land reclamation are important for this image, which should take into account various factors describing the mining area, including social preferences. The article presents an example solution – fuzzy system (FSDR) – which supports the selection of the direction of reclamation of post-mining areas created after the termination of operations of open pit gravel and sand natural aggregate mines. The article presents selected factors determining the selection of the direction and possible reclamation variants as input and output data of the fuzzy system. The rules base of the developed system, as well as the mechanisms of inference and defuzzification, were also characterized. The application of the developed system is presented on selected examples.
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