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Efficiency improvement of forest machinery exploitation

Diagnostyka 2020年第2期21卷 95-109页

作者： Grigorev, Igor Kunickaya, Ol'ga Prosuzhih, Alexey Kruchinin, Igor Shakirzyanov, Dmitry Shvetsova, Viktoria Markov, Oleg Egipko, Sergey Department of Technology and Equipment of Forest Complex Yakut State Agricultural Academy Yakutsk Russia Department of Logging Technology and Machines Ukhta State Technical University Ukhta Russia Department of Transport and Road Construction Ural State Forestry University Ekaterinburg Russia Department of Engineering of Technological Machines and Equipment Ukhta State Technical University Ukhta Russia Department of Descriptive Geometry and Engineering Graphics Saint-Petersburg State University Architecture and Civil Engineering Saint-Petersburg Russia Department of General Technical Subjects Federal State Budget Educational Institution of Higher Education petrozavodsk State University Petrozavodsk Russia Department Machines Environmental Engineering Don State Agrarian University Novocherkassk Russia

The purpose of this work was to develop a model of the interaction process between the wheeled forwarder and the soil of the cutting area, which allows evaluating the influence of soil conditions, the parameters of the wheeled forwarder, as well as load and number of cycles of its application, on the indicators of resistance and adhesion of the forwarder to the traction surface. Modeling results for 3-and 4-Axle forest machines with different load levels showed that for different soil categories, types of bodies, and tire sizes. The results of the approximation analysis enabled the derive of calculation formulas for estimating the propulsive coefficient and rut depth after the first passage depending on the values of load-bearing capacity, body load coefficient, wheel width, and soil deformation module. The proposed model can be used at laying down the skidding roads and its optimization not only in economic terms but also with respect to the environment as intensive harvesting operations lead to extensive soil destructions. The practical application of the results is expressed in increased performance capacities of wood skidding operations and minimization of costs for restoring the productivity of forest area. © 2020 Polish Society of Technical Diagnostics. All rights reserved.

关键词： Soils

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The use of modeling in the teaching of geometry and graphic disciplines at the University

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Journal of Physics: Conference Series 2021年第1期2001卷

作者： Ekaterina A Vanshina Olga N Shevchenko Olga N Malikova Oksana L Staselko Irina V Shusharina associate Professor of Department of descriptive geometry engineering and computer graphics FSBEI 'Orenburg state University' 13 Pobedy Ave. Orenburg 460018 Russia head of the Department of descriptive geometry engineering and computer graphics FSBEI 'Orenburg state University' 13 Pobedy Ave. Orenburg 460018 Russia associate Professor of Department of descriptive geometry and graphics FSBEIHE 'Industrial University of Tyumen' 2 UL. Lunacharskogo Tyumen 625001 Russia senior lecturer of the Department of descriptive geometry and graphics FSBEIHE 'Industrial University of Tyumen' 2 UL. Lunacharskogo Tyumen 625001 Russia

1. Introduction: In connection with the introduction of new Federal state educational standards of higher education (FSES) to teachers of geometry graphic departments there was a problem with the revision of the contents and methodology of teaching disciplines 'descriptive geometry', 'engineering and computer graphics', foundations of engineering education aimed at formation of basic knowledge for studying of the subsequent disciplines used graphic representation of information. The analysis of special literature has indicated that, despite the significant number of scientific publications on the research topic, the use of modeling in teaching geometric-graphic disciplines requires separate research. 2. Materials and methods: Study and analysis of scientific, educational and special literature on the research topic, comparison, systematization, synthesis, generalization. 3. Results: To implement modern teaching methods in the educational process in the geometric-graphic disciplines, the author applied the functionality of the system KOMPAS-3D and developed by: electronic slides based on the modeling included in the evaluation funds for engineering and computer graphics; set a clear three-dimensional (3D) models of twenty-assemblies products intended for assignments on practical and laboratory lessons on the computer in the system KOMPAS-3D to create an Assembly and working drawings; set of individual tasks designed to practical assignments on the computer in this system to create 2D-models of assemblies (Assembly drawings) and 2D models details (working drawings), associated with their three-dimensional models. 4. Discussion and Conclusions: Design and creation of didactic materials based on three-dimensional and flat modeling tools, methods and algorithms of computer graphics in the system KOMPAS-3D, their use in teaching geometric-graphic disciplines, the inclusion in the evaluation funds on descriptive geometry, engineering and computer graphics, contributes to t

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Ocular hypertension in patients with central/hemicentral retinal vein occlusions： cumulative prevalence and management

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International Journal of Ophthalmology(English edition) 2018年第7期11卷 1173-1178页

作者： Dan Calugaru Mihai Calugaru Stefan Talu Department of Ophthalmology University of Medicine Cluj-Napoca 400467 Romania Department of AET Discipline of Descriptive Geometry and Engineering Graphics Faculty of Mechanical EngineeringTechnical University of Cluj-Napoca Cluj-Napoca 400012Romania

AIM： To prospectively evaluate the cumulative prevalence and the management of ocular hypertension（OH） in patients with unilateral acute central/hemicentral retinal vein occlusions（C/HCRVOs） over the course of 3 y. METHODS： The study included 57 patients with unilateral acute C/HCRVOs. All patients underwent a comprehensive ophthalmological examination of both eyes. OH associated with C/HCRVO in patients showing a score 〉5% for the risk of conversion to primary open angle glaucoma（POAG） was treated with OH medication. The treatment aimed for a decrease in intraocular pressure（IOP） to 〈21 mm Hg with a 〉22% reduction from the initial values. The cumulative prevalence of OH and the effectiveness of treatment assessed by the cumulative prevalence of conversion from OH to POAG, were estimated. RESULTS： Fifteen patients had OH associated with C/HCRVOs, the cumulative prevalence of OH was 29.4%（95% confidence interval, 16.9-41.9）. The mean value of the risk score of OH conversion to POAG for the 5 subsequent years was 11.7%±5.4%. The IOP significantly decreased from 25.67±2.16 mm Hg to 18.73±2.96 mm Hg. None of the OH patients converted to POAG during the follow-up period. CONCLUSION： The increased cumulative prevalence of OH in C/HCRVO patients indicates that OH is a risk factor for the appearance of venous occlusion. Patients with OH associated with C/HCRVO must be considered to be at high risk for conversion to POAG. Treatment with OH medications prevented conversion to POAG during the 3-year follow-up.

关键词： ocular hypertension acute central/hemicentral retinal vein occlusion intraocular pressure primary openangle glaucoma risk factor

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Influence of thermomechanical treatment modes on wear resistance of mining equipment material

Influence of thermomechanical treatment modes on wear resist...

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International Scientific Conference on FarEastCon, ISCFEC 2018

作者： Chupin, S. Bolobov, V. Department of Descriptive Geometry and Engineering Graphics Saint Petersburg Mining University Saint Petersburg Russia Department of Mechanical Engineering Saint Petersburg Mining University Saint Petersburg Russia

ISBN: (纸本)9783035712926

This work presents results of experimental researches of influence of various hightemperature thermomechanical treatment (HTMT) modes in 35KhGSA steel – material applied in rock-destroying cutters – on hardness and wear rate for the most common abrasive rock in mining operations – sandstone. It has been found out that HTMT leads to increase of steel hardness and reduction of wear rate compared to heat treatment applied at manufacture of cutters. The maximal increase of hardness (by 23%) and reduction of wear rate (by 38%) corresponds to the mode of distortion accumulation of ∼1,5 at 900 ° at water quenching and tempering at 230 °C. A conclusion that thermomechanical treatment is an effective way to increase the wear resistance of steels applied in the conditions of abrasion wear has been drawn. © 2019 Trans Tech Publications, Switzerland.

关键词： Hardness

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Theoretical studies of dynamic soil compaction by wheeled forestry machines

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Diagnostyka 2020年第4期21卷 3-13页

作者： GRIGOREV, Igor KUNICKAYA, Ol'ga BURGONUTDINOV, Albert IVANOV, Viktor SHUVALOVA, Svetlana SHVETSOVA, Viktoria STEPANISHCHEVA, Marina TIKHONOV, Evgeniy Department of Technology and Equipment of Forest Complex Yakut State Agricultural Academy Yakutsk Russia Department of Roads and Bridges Building Perm National Research Polytechnic University Perm Russia Bratsk State University Bratsk Russia Department of Descriptive Geometry and Engineering Graphics Saint Petersburg State University of Architecture and Civil Engineering Saint-Petersburg Russia Department of Reproduction and Processing of Forest Resources Bratsk State University Bratsk Russia Department of Transport and Technological Machinery and Equipment Federal State Budget Educational Institution of Higher Education "Petrozavodsk State University" Petrozavodsk Russia

The impact of forest skidding machine tires on the soil differs depending on topography, soil properties, and type of the wheel system. The development of a mathematical model describing the entire dynamic process is a challenging but relevant task to assess the level of impact. The work aims mathematical modeling of the impact caused by the skidding system on the forest soil employing Kelvin-Voigt theory with additional elastic element and Laplace transform equations. A dynamic model represents the "tractor-timber bundle-soil" system. According to the results of mathematical modeling, it was found that studying the vertical vibrations and vibrations of sprung mass in longitudinal and transverse planes is sufficient for examining dynamic soil compaction. Developed methods of statistical dynamics with the presentation of the track surface microroughness and the theory of linear elastic and viscous soil deformation showed that each pass of the skidding system is ac-companied by additional dynamic soil compaction. Its maximum value depends on the properties of the soil and skidding system, as well as on the presence of resonant zones in the frequency spectrum. The results of these studies provide an opportunity to predict the exposure level of skidders and establish new solutions to minimize negative consequences for the environment and productivity of the forest industry. © 2020 Polish Society of Technical Diagnostics. All rights reserved.

关键词： Laplace transforms

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On the Wear Intensity Ratio of a Striker under Dynamic and Static Conditions

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IOP Conference Series: Earth and Environmental Science 2020年第6期459卷

作者： V Bolobov S Chupin Le Thanh Binh Department of Mechanical Engineering Saint Petersburg Mining University Saint Petersburg Russia Department of Descriptive Geometry and Engineering Graphics Saint Petersburg Mining University Saint Petersburg Russia

The results of experiments on determination of the cylindrical part mass loss of the cone-shaped strikers made of 38XM (AISI P20), У8 (AISI W1-A), and X12MФA (AISI D2) steels, which have been subjected to heat treatment applied by the striking tools manufacturers, and additional cold treatment, with their friction and abrasive wear on granite, are presented. It was found that the strikers made of steel X12MФA with all types of heat treatment show the greatest wear resistance under the wear conditions (static conditions), while the strikers made of 38XM have the lowest wear resistance. Cryogenic treatment and, to a lesser extent, cold treatment increase the wear resistance of all materials. The comparison of set values of wear resistance Ist and hardness HV of the strikers, as well as the analysis of their microstructure allows to conclude that wear resistance of a tool depends not only on its hardness, but also on the type, volume, shape of carbides forming the structure of material used for tool manufacturing. For this reason, after the cryogenic treatment, the tool made of X12MФA steel shows the greatest wear resistance, because its material has the highest content of carbon (~1.5%) and alloying elements (~13%), which provides up to 10.8% increase in the number of fine carbide particles in its structure, that ensure wear resistance increase, after the cold treatment. The results obtained for Ist are compared with the earlier obtained data on wear resistance of the same striker at striking upon granite (in dynamic conditions). The conclusion about similarity of the wear mechanisms of the analyzed strikers in dynamic and static conditions is made.

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Directions For Improving the Efficiency of Forest Clear Cutting on the Territories of Reservoirs and Waterworks Under Construction

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IOP Conference Series: Earth and Environmental Science 2020年第1期574卷

作者： V Kalyashov A Iliin S Shuvalova O Leonova V Shvetsova Department of descriptive geometry and engineering graphics Saint Petersburg state University of architecture and civil engineering 4 2nd Krasnoarmeiskaya Street Saint Petersburg 190005 Russian Federation Department of water energy and ecological feasibility JSC Lenhydroproject Ispitateley prospect 22 Saint Petersburg 197227 Russian Federation

The article deals with the issues of increasing the forest resources use extent on the forested areas of reservoirs' flooded territories of hydroelectric power stations (HPPs) – both projected and under construction- in multi-forest areas of the Russian Federation. The necessity of forest clear cutting and forest clearing carrying out on flooded territories and the importance of these measures for ensuring favorable environmental conditions in the area of hydro construction and in the water area of reservoirs are substantiated. The estimation of the wood volume cut in the process of reservoirs creation is presented and the reasons for leaving wood to be flooded are considered. The factors and circumstances that affect the indicators of economic efficiency of forest clear cutting are described. A comparative assessment of the applied technologies of forest clear cutting is made, ways to increase its profitability are outlined, and the impact of profitability on decision making on leaving wood to be flooded in the process of reservoirs' territory preparation is estimated.

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Problems of technological processes selection in logging

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IOP Conference Series: Materials Science and engineering 2020年第1期817卷

作者： V Kalyashov A Smirnova N Tjurin L Gromskaya T Antonova Descriptive Geometry and Engineering Graphics Department Saint Petersburg State University of Architecture and Civil Engineering 4 2-nd Krasnoarmeyskaya Street Saint Petersburg 190005 Russian Federation Department of forest policy Economics and management St. Petersburg State Forest Technical University 5 Institutskiy Lane St. Petersburg 194021 Russian Federation Department of Industrial Transport St. Petersburg State Forest Technical University 5 Institutskiy Lane St. Petersburg 194021 Russian Federation

The article deals with current issues of the logging enterprises effective functioning with assortment technology for wood harvesting in the Leningrad region of the North-West Federal District of Russia. A survey of the production activity of a number of enterprises that use logging technology based on harvesters and forwarders was carried out. The results of technical and economic assessment of this technology usage are presented, the reasons of the decrease in the efficiency of the technological process of the logging are identified, the alternative assortment technologies are considered, and recommendations on selection of technological processes and systems of logging machines are made.

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Projecting by conical screw lines with constant step

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IOP Conference Series: Materials Science and engineering 2018年第1期451卷

作者： E V Denisova M V Voronina Z O Tretyakova Department of Descriptive Geometry and Engineering Graphics Saint-Petersburg State University of Architecture and Civil Engineering 4 2-ya Krasnoarmeiskaya st. Saint Petersburg 199105 Russia Department of Descriptive Geometry and Graphics Saint-Petersburg Mining University 2 21st Line Saint Petersburg 199106 Russia

The relevance of the study: The formation of surfaces by analytical methods and their visualization using computer graphics is one of the topical problems of applied geometry. Purpose of the study is to investigate non-traditional projection systems, to select congruence parameters of conical helical lines that cover the entire complex of surface requirements, obtained by projecting with conic rays an arbitrary flat or spatial line and using computer graphics in visualization of the surface. Methods of research: The general analytical theory of applied surface molding, developed by prof. Skidan I A and a single unit, which is based on the mathematical support of computer technologies for designing and creating objects of complex shape. Results of the research: An example of an analytical interpretation of the image of curvilinear projection by conical screw lines of a constant step and an example of congruence of conical screw lines, located on coaxial cones with a common vertex and a variable angle of inclination of the generator to the axis. The properties are investigated, the parameters of the helical line of the congruence, passing through an arbitrary point of space that does not belong to the axis, are determined. A method is proposed for constructing spiral surfaces, the framework of which consists of rays projecting an arbitrary line.

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Analysis and Recommendations for Education Process of Experts in the Field of Scanning Probe Microscopy

Analysis and Recommendations for Education Process of Expert...

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2017 4th International Conference on Advanced Education Technology and Management Science(AETMS 2017)

作者： ?tefan T?LU Dinara SOBOLA Nikola PAPE? Technical University of Cluj-Napoca Faculty of Mechanical Engineering Department of AETDiscipline of Descriptive Geometry and Engineering Graphics Brno University of Technology Faculty of Electrical Engineering and Communication Department of Physics

This paper describes the mandatory conditions for training specialists in the widespread and still continuously developing microscopic technique for studying of materials surface. Traditional methods of education are not sufficient for teaching of the multidisciplinary subjects. Available information technologies and resources alone do not ensure learning success. There is need for a conceptual review and analysis of the cases in the sphere of specialists training. Scanning probe microscopy is based on the fundamental concepts of quantum mechanics, physics, chemistry, etc. In this regard, the specialist has to achieve knowledges in the field of science(physical and chemical laws), and at the same time there is necessity to be educated in approaches for the study and description of surface quality.

关键词： Modern teaching Study methodology Microscopy technique

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