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Date submitted2024-04-27
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Date accepted2024-11-07
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Date published2025-03-05
Comprehensive studies of the snow-firn layer in the area of the Russian Antarctic Vostok Station
The article presents the findings from research conducted at Vostok Station during the 69th Russian Antarctic expedition. The primary goal of the research is to perform a thorough investigation of the snow-firn layer using both direct (drilling and core analysis) and indirect (georadiolocation and seismic exploration) methods. As part of the research, fundamental tasks related to the study of the structure and dynamics of the upper part of the ice sheet were addressed, as well as applied tasks aimed at justifying the depth of explosive charge placement for seismic work with the goal of conducting a detailed study of Lake Vostok and selecting the point for drilling access to the lake. Data on the microstructure and physical properties of the snow-firn layer were collected. The findings will allow for future improvements to the firn densification model, which is required to understand the evolution of ice grains during the early stages of metamorphism. The study's findings aided in the understanding of the structural features of the ice sheet's surface layer, allowing for more precise determination of the structural and physical characteristics of the snow-firn layer and ice, potentially leading to a better understanding of climatic and geological processes in Antarctica.
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Date submitted2022-09-26
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Date accepted2023-09-20
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Date published2024-04-25
Technology of absorption elimination with cross-linking plugging material based on cement and cross-linked polymer
The peculiarity of the geological structure of carbonate reservoirs is their complex permeability and porosity characteristics, reflecting the simultaneous presence of cavities variety (fractures, caverns, pores). Loss of circulation during penetration of fractured rock intervals significantly increases well construction time due to lack of efficient plugging isolation compositions. The main disadvantages of traditional compositions are high sensitivity to dilution in the process of their injection into the absorption zone, as well as insufficient structural strength to prevent the isolation composition from spreading during the induction period. For efficient isolation of catastrophic absorption zones in conditions of high opening of absorption channels a new cross-linking plugging isolation composition has been developed, which allows to exclude disadvantages of traditional isolation compositions. Application of the composition will allow to reduce the injection volume of the isolation composition and the time of isolation works due to its resistance to dilution and movement of formation water in the absorption interval.
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Date submitted2020-07-22
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Date accepted2020-11-12
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Date published2020-12-29
Simulation of the electric drive of the shearer to assess the energy efficiency indicators of the power supply system
- Authors:
- Vyacheslav A. Voronin
- Fedor S. Nepsha
This paper considers the problem of electric drive of shearers simulation to assess the indicators of power supply system (PSS) energy efficiency in the context of the introduction of modern devices for controlling the flow of electricity and power. The block diagram of the shearer electric drive simulation model is presented. To take into account fluctuations in the level of consumption of active and reactive power, a model of the executive body of the shearer was used in the work, including a model of the moment of resistance on the auger when cutting. As a result, in the MATLAB Simulink environment, a simulation model of the electric drive of the UKD300 shearer was developed, suitable for assessing the energy efficiency of the electrical complex of mining areas and the feasibility of using modern devices for controlling the flow of electricity and power. As a result of the simulation, it was found that a significant irregularity in the graph of reactive power consumption, caused by repeated short-term operation, makes the use of capacitor units ineffective to compensate for reactive power.
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Date submitted2019-05-07
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Date accepted2019-07-11
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Date published2019-10-23
Operation of a Single-phase Autonomous Inverter as a Part of a Low-power Wind Complex
- Authors:
- A. A. Belsky
- V. S. Dobush
- Shaiban Fuad Haikal
The article discusses the experience of operating a wind power complex with a low-power wind power installa- tion (5 kW), the use of which is promising for powering remote oil production facilities, exploration and other types of mining operations. The structure of the studied complex and its characteristics, technical problems that have arisen during operation for 6 years are given. The elements of the wind energy complex – the battery charge regulator and the inverter-converter are considered. The consequences of the mechanical regulator failure of battery charge are con- sidered and recommendations for its replacement are presented. The issues of diagnostics and repair of one of the main elements of the complex – the inverter-converter, its component – DC link are highlighted in detail. Oscil- lograms of the output voltage of the inverter-converter are presented for different capacities of the DC link and the images of the repaired inverter-converter are given. Recommendations are given on choosing an inverter-converter and setting up the operating modes of the wind energycomplex.
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Date submitted2015-12-18
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Date accepted2016-02-01
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Date published2016-12-23
Simulation of onboard power supply system for small hydrographic vessel «Vaygach»
- Authors:
- I. A. Pankov
- V. Ya. Frolov
Computer simulation is a method resorted to more and more frequently for the development of the prospective power supply systems, in particular the vessel power supply system. It provides valuable insights into the transient processes and indicators of electric power quality in the system without building its physical model, thus significantly improving the efficiency and quality of the physical model. Nowadays MathLab package with Simulink application is used with increasing frequency for simulation of such systems. The paper presents a model of the power supply system of small hydrographic vessel ‘Vaygach’ built in MatLab environment. The system vulnerabilities and their remedies have been identified. Changes in sinusoid before and after the non-linear load on the network have been demonstrated and solutions for improving the non-linear distortion factor are proposed. The model developed for the vessel power supply system can be used for building models of different vessels.