The Yakutsk Extensive Air Shower Array has been continuously operating for more than 50 years (since 1970) and up until recently it has been one of world’s largest ground-based instruments aimed at ...studying the properties of cosmic rays in the ultra-high energy domain. In this report we discuss results recently obtained at the array—on cosmic rays’ energy spectrum, mass composition and directional anisotropy—and how they fit into the world data. Special attention is paid to the measurements of muonic component of extensive air showers. Theoretical results of particle acceleration at shocks are also briefly reviewed. Future scientific and engineering plans on the array modernization are discussed.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Abstract
The article discusses the analysis and assessment of the optimal direction of the horizontal wellbore and its spatial location relative to the minimum and maximum reservoir stresses play a ...significant role in the design of an operation to create multiple hydraulic fractures. Theoretically, two cases are possible: the horizontal wellbore is located strictly in the direction of maximum horizontal stress; the horizontal wellbore is located strictly in the direction of the minimum horizontal stress. As a conclusion based on the hydraulic fracturing design, the well productivity factor was calculated and compared for longitudinal and transverse fractures; longitudinal fractures have a clear advantage. According to the presented calculation, the hydraulic fracturing method will have advantages in a horizontal well in a highly permeable reservoir. The hydraulic fracturing method will increase the vertical permeability. According to the presented calculation, the hydraulic fracturing method will have advantages in a horizontal well in a highly permeable reservoir. The hydraulic fracturing method will increase the vertical permeability and unite the disparate parts of the reservoir. The hydraulic fracturing method will increase the vertical permeability and unite the disparate parts of the reservoir, which will make it possible to more efficiently develop the reserves of the Neocomian deposits in the field.
The use of modern computer aided methods, in particular the use of the Micromine software, is an important part of the integrated research for the determination of deposit prospects for various ores. ...The paper is devoted to the analysis of prospects and estimation of reserves for open-pit and underground mining in the Berezkinskoye ore field. For this purpose, silver reserves were determined as the principal valuable component. The deposit balance reserves were estimated separately for all types of ores in the optimal open pit envelope adopted in the final mining feasibility study (FS of permanent exploration conditions for ore extraction). To vectorize and verify the geological information entered into the database, graphical materials in the form of cross-sections and plans with the corresponding borehole database were georeferenced using the Micromine software. The final inspection was carried out to ensure that the sample depth information entered was consistent with the excavation depth. The database contains information on the location of boreholes and trenches, the design of boreholes, the spatial positioning of the boreholes/trenches axes, the data of sample assays for silver and copper. For underground mining, the delineation of ore bodies was carried out based on the cross-sections identified in the boreholes at a cut-off grade of 10.7 g/t, taking into account the orientation of geological structures. Reliability of the ore bodies delineation was verified in a Micromine three-dimensional model. For open-pit mining, the position of small ore bodies may be clarified by operational exploration with possible subsequent upgrading their reserve categories. The wireframe model of ore zones and bodies was constructed using the outlines obtained by the developed methodology. A wireframe model of faults was based on the Berezkinsky area plans and cross-sections. The construction of the fault wireframe model was performed in several steps. Application of modern geoinformation system (GIS) technologies makes it possible to qualitatively assess the prospects and estimate the reserves at the deposits. The Berezkinskoye deposit ore material composition, metallurgical properties, hydrogeological and geotechnical features were investigated.
X-ray diffraction analysis is essential in studying stacking faults. Most of the techniques used for this purpose are based on theoretical studies. These studies suggest that the observed diffraction ...patterns are caused by random stacking faults in crystals. In reality, however, the condition of randomness for stacking faults may be violated. The purpose of the study was to develop a technique that can be used to calculate the diffraction effects of the axis of the thin plates of twin, new phases, as well as other variations in defective structures. Materials and methods. This was achieved through modern X-ray diffraction methods using differential equations (transformations and Fourier transforms) and the construction of the Ewald sphere, mathematical analysis, mathematical logic, and mathematical modeling (complex Markov chain). Conclusion. The study made it possible to develop a technique for the calculation of the diffraction effects of the axis of the thin plates of twin, new phases and other variations in defective structures. The technique makes it possible to solve several complex, urgent problems related to the calculation of X-ray diffraction for crystals with face-centered lattices containing different types of stacking faults. At the same time, special attention was paid to the correlations between the relative positions of faults. The calculations showed that the proposed method can help to determine the nature and structure of stacking faults by identifying the partial and vertex dislocations limiting them in twin crystals with a face-centered cubic structure of silicon carbide based on X-ray diffraction analysis.
Underground mining, including underground coal mining, is accompanied by accidents and fire hazards that pose a threat to the life safety of miners. The fire hazard increases with an increase in the ...mining depth. Currently, most accidents in coal mines are mine fires. The cost of eliminating mine fires is 80–95% of the cost of eliminating all accidents occurring at mining enterprises. Therefore, the problem of developing a new methodology for modeling the ventilation network parameters of the mine to increase the reliability of controlling the aerogas mode at the excavation site is very relevant. The comprehensive analysis and assessment of gas-dynamic processes in coalmines under study were carried out using the methods of probability theory and mathematical statistics. Spatial data were processed using spline interpolation in “gnuplot”. As a result, a generalized expression for the transfer functions of coalmine objects, taking into account delays, was developed, including the description of dynamic properties of mining sites under various operating modes. The principal possibility of using a graphical method for estimating additional parameters of the sections of the ventilation system branches has been proved due to the alignment of their profiles at an equivalent distance relative to an arbitrary analogue. The improved method of spatial modeling was used to determine the gas-dynamic characteristics through additive gas-dynamic processes. The studies have been carried out and the method for managing the process of changing connections between devices (controllers–switches) of the technical system was developed in order to obtain greater reliability for safe mining. In subsequent studies, there is an issue of more detailed clarification of the peculiarities concerning the interrelations between the studied parameters in several projections of the response space.
The structural scheme of the automated control system of power consumption at the industrial enterprise is developed in the article. At the non-ferrous metallurgy enterprise, an energy inspection and ...a rank analysis of the electrical energy consumption of the main processing equipment were carried out. It is established that the enterprises of non-ferrous metallurgy are a complex process system consisting of a set of thousands of jointly functioning technological facilities. For the most effective estimation of power consumption of enterprises, it is reasonable to use the automated system of dispatching control of power consumption (ASDCPC). The paper presents the results of the development of the ASDCPC structural diagram that allows one to perform on-line control and management of the energy and process parameters of the main production units and the enterprise as a whole. As a result of the introduction of ASDCPC at the non-ferrous metallurgy enterprise, the consumed active power was reduced during the peak hours of the load by 20%, the specific electricity consumption - by 14%, the cost of the energy component in the cost of production of hard alloys - by 3%.
The oil and gas industry has been an integral and fundamental sector of the Russian economy for the past few years. The main problems of this industry have traditionally been the deteriorating ...structure of oil reserves; depreciation of main assets; slowdown and decline in oil production. Recently these have been complicated by a number of new negative trends related to underinvestment, limited financial resources, deteriorating access to new equipment and technologies. The task of the research is to make a comprehensive assessment of hydraulic fracturing technology during well construction and to increase the recovery and intensification of hydrocarbons production. In this research, modeling techniques were used to assess the productivity of each fracture. Geophysical methods (seismic survey) were used to determine the geomechanical properties of the formation. Comprehensive assessment of hydraulic fracturing technology during well construction was carried out, which allowed to increase vertical permeability and unite disparate parts of the reservoir in practice, and to determine the development efficiency of the hydrocarbon field.
Quartz resources play a crucial role in the development of key economic sectors, particularly in the production of chemically pure silicon. The extraction and processing of these resources ...necessitate high-tech methods to obtain the desired silicon output. Presently, the demand for silicon stands at 5–6 Ktpa, while the supply remains at 2300 t. An analysis of the chemical properties of various rocks (quartzites, quartz sands, vein quartz) in the Republic of North Ossetia–Alania reveals that their parametric characteristics align with the requirements for silicon production. The researchers in North Ossetia have successfully grown singlecrystal silicon and produced photovoltaic converters. Russian scientists have also achieved the first melting of metallurgical silicon into polycrystalline silicon using vacuum furnaces and electron-beam remelting, yielding promising results. The goal of this research is to analyze and assess the potential of high-quality quartz resources in the North Caucasus. The main objectives include identifying sites with optimal quartz deposits suitable for silicon production, conducting localization, estimating forecast resources, and designating areas for further investigation. The selected sites are expected to possess advantageous geographical and economic features, along with favorable mining conditions conducive to open-pit mining.
The study focuses on the Fiagdon site in the Alagir District, RNO-Alania. Various methods, including laboratory work, sampling, examination of constructed sections, and a comprehensive review of mine workings and borehole documentation, were employed. Conclusions from mineralogical and petrographic analyses, alongside laboratory studies and process tests, contributed to the research methodology. The results of the research encompassed the analysis of statistical, economic, geological, and process-related information necessary for addressing primary geological objectives. Subsequent steps involved the selection of prospects for further exploration, specification of geological maps at a 1:10000 scale with accompanying legends and sections, determination of the conditions, morphology, and parameters of productive deposits, and preliminary studies on the quality and process characteristics of quartz resources. Furthermore, the P2 forecast resources of high-quality quartz raw materials for silicon production were localized, estimated at 500 Kt, and rigorously tested. The study’s discoveries have led to the formulation of recommendations for future exploration endeavors.
Abstract
To solve the problems of controlling the gas-dynamic processes of production areas and air distribution in the ventilation network, their mathematical description is required, which can be ...obtained only on the basis of a detailed study and determination of the parameters and characteristics of gas-dynamic processes and regularities of air distribution. The mathematical description of the production ventilation system is complicated by the fact that the variables that determine the state of the control system are random functions of time. Therefore, the main attention should be paid to determining the probabilities of the characteristics of aerogasdynamic processes. The mathematical description of the ventilation of the production area into static and dynamic characteristics was the basis for the development of an optimal control algorithm for the production area. The control algorithm for the ventilation of the mining area consists of subalgorithms for controlling the parameters of the mine atmosphere, primary processing of the received information, and generating control actions. Their development is possible on the basis of research and mathematical description of gas-dynamic processes and methods for controlling the parameters of the mine atmosphere. Effective control of gas-dynamic processes in production areas is possible only when considering the entire ventilation system, due to the interconnectedness of aerodynamic parameters. The task of optimal air distribution control in the network is to ensure the required airflow rates for ventilation, determined as a result of solving the first problem with minimal energy costs for ventilation.
At the present stage, most oil and gas condensate fields in the southern part of the East Siberian oil and gas province are characterized by an increasing proportion of difficult oil reserves in ...tight reservoirs. Multistage hydraulic fracturing (MHF) is proposed for the offshore Challenger Sea field (Southeast Dome). The implementation of this technique at a shelf will be a source of additional risks. For example, the properties of the RR-2 overlying seal have not been unambiguously assessed, and there are a number of geological uncertainties, such as the tectonic regime. However, there are a number of arguments in favor of MHF: heterogeneity of the reservoir; low permeability; low water cut of the field; sufficient thickness of the pay zone; and the overlying seal. One more positive factor is that sand ingress is not observed in the process of oil production. The selection of a principal well completion scheme on the eastern side of the RR-7 formation is aimed at effectively recovering the remaining reserves. The objectives of the study performed are: to create a geological and hydrodynamic model of the Challenger Sea (Southeast Dome); develop 1D and 3D geomechanical models; evaluate oil production forecasts based on fundamentally different well completion schemes; and determine the optimum parameters for multistage hydraulic fracturing. The research methods included: petrophysical methods; logging methods; core studies; drilling reports and formation testing data; and 3D, 4D geomechanical simulation. Other geophysical methods included acoustic logging, density logging, and gamma-ray logging. After building a geomechanical model of the reservoir at the beginning of drilling, a hydrodynamic calculation was performed. This established the reservoir pressures and saturations at certain points in time. The results made it possible for the principal stress directions, the values of effective and principal stresses, and the values of elastic strains to be determined. In order to assess MGF process efficiency, production forecasts were made using a hydrodynamic model for an exploration well with conventional completion (perforated liner) and with five-stage MGF. In the first case, the accumulated production was 144 kt over 15 years, and in the second case, 125 kt over 17 years. The difference in cumulative production is due to different initial well flow rates, as well as the rate of oil withdrawal during the first few years of development. Thereafter, the production and daily flow rate curves showed similar behavior. In order to select the most effective option, an economic analysis of the efficiency was performed.
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