05.00.00 Technical science
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TO SUBSTANTIATE A VEHICLE SPEED WHEN CONDUCTING HARVESTING OF FIELD WORKS
DescriptionA more efficient use of road transport can be reached both by increasing the carrying capacity of the car and the average speed on the road. Due to limiting the safe load on the axle of the vehicle, a more promising solution is to increase the average speed on the road. Restricting car traffic speed on the roads with asphalt-concrete surface is due to the traffic safety, defined as resistance, steerabililty, vibrations of steering wheels and braking dynamics of the vehicle. The first three factors are influenced by the functional characteristics of the suspension and the state of the road surface. The share of agricultural vehicles mealage on the roads with improved surface does not exceed 65%. Nowadays, 40% of traffic volume and 9% of transport mealage are due to the transportation from the field and to the field. The aim of this work was to study the vibrational load of the load-carrying system and the driver, as well as the vehicle speed during the harvest time. To carry out theoretical research we used mathematical model "vehicle-road" system proposed by V.P. Tarasik. As a result of research we obtained the dependence of the acceleration of the front axle on the vehicle speed. The results showed that the maximum acceleration of the front axle is observed at a speed V = 20 km / h, which corresponds to external influences 1.54 Hz (9.7 rad/sec). The peak values of the vertical acceleration amounted to 5.80 m/s 2. The correctness of the mathematical model was verified by comparing the results of theoretical and experimental research in the mode of uniform motion. The experimental determination of the vibrations of the vehicle sprung mass was carried out using the sound level meter and spectrum analyzer OKTAVA-101 AM, which is equipped with a vibrational pickup AP 98. The given calculations showed that the relative error of the results of theoretical and experimental research is 3.94%, the average value of an error at a confidence coefficient of P = 0.95 is 4.76%, which confirms the correctness of the mathematical model. The studies showed that if the speed is between 14 to 40 km / h, the vibrational load on the driver is from 1.42 m/s 2 to 2.82 m/s 2, that is 2.5 ...3.5 times the sanitary standards set by the requirements of the CH 2.2.4/2.1.8.566 - 96
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Description
The article is devoted to solving one of the major problems in electric power industry, which is to simplify and improve the accuracy of simulation and calculation modes of complex electrical systems with using the frequency characteristics of the elements of the power system in generalized vector space. Article has an exploratory character, which is expressed that mathematical models of static elements of an electrical network are considered in the form of transfer functions of dependence of conduction on the frequency. A number of the provisions of article has scientific originality which is in the approach to the choice of the coordinate system for modeling static elements. It is offered the mathematical models air and cable transmission lines, generalized load, single reactors generalized vector space for analysis of steady and transient modes. As an example was calculated family of real and imaginary parts of the frequency characteristics of the AC-70 line with different values of the length, lines with different section (AC-70, AC- 95, AC-120), generalized load with different ratios of active and reactive power, various types of single reactors. Offered mathematical models allow exploring different symmetric modes of electric networks using more efficient mathematical apparatus
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ERROR CHECK IN OPERATING CRYPTOGRAPHICALLY SECURE PSEUDORANDOM NUMBER GENERATORS
DescriptionAlgorithms and constructing schemes of trusted pseudorandom number generators (PRNG) based on multivalued codes of residue number system are presented. An algorithm for numerical control of the operation of arithmetic adder Zm, differing by the introduction of various rules for performing the operation of "forming" of the overflow flag bit and the correction operation of the supervision data adjusting is developed. A scheme for local control of the adder Zm, which differs from the known by introduction of the overflow flag bit generation scheme and accounting scheme of the supervision data adjusting is constructed. End-to-end monitoring scheme of modular adder control and key storage device (KSD) for holding the crypto key with residual class code is constructed. The proposed scheme differs from the known by additional memory page, overflow flag bit generation scheme and by accounting scheme of the supervision data adjusting. The results of a comparative evaluation of the developed pattern for local and end-to-end monitoring of modular adder control with hardware redundancy are provided. Based on the results of the comparative evaluation it is expedient to use the modular control method in order to increase the reliability of the PRNG. At the same time, the developed algorithms and end-to-end monitoring schemes ensure elimination of the fracture areas in the control and expansion of fragments of the local (intermediate) PRNG control with minimal hardware and time redundancy. Application field of the developed algorithms and control schemes are digital devices with cryptographic functions
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Description
The article deals with the study of vehicles impact on the environment, since one of the main causes of air pollution are cars with internal combustion engines. One of the most important measures in the fight for clean air is the creation of an environmentally friendly transport. From this point of view, the most promising is the electric car, as the only solution to the problem of atmospheric pollution. In this article, the history of the development of modern electric vehicles, the advantages and disadvantages of their design, as well as the possibility of introducing electric vehicles into everyday life are considered. After the analysis, it was concluded that, in spite of the obvious advantages and the huge path that electro mobiles went through in their development, humanity is still not ready to refuse from cars with internal combustion engines, opting for electric vehicles
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SECURITY ASSESSMENT PROBLEMS IN SAWMILL EQUIPMENT
DescriptionThe article deals with normative legal documents, regulating safety indicators of equipment, with particular focus on woodworking machinery, including log-processing equipment. General and specific requirements have been highlighted in terms of their analyses. The necessity of safety requirements’ specification in technical guidelines, with reference to construction of industry-specific trend equipment, according to newly accepted national, interstate and international standards for purposes of conformity assessment. Nonconformities were determined on the terms in Technical Guidelines of the Customs Union 021/2011, fundamental documents for woodworking equipment GOST EH 1070 and GOST ISO 12100. Relevant topic issues are declared in this work. Manufactures consider them when risk valuation is performed in point of existing equipment and that, under development non-standard equipment, connected with diversity of normative documents, absence of information about customers’ experience, accidents while operating comparable machinery, etc. The paper emphasizes complications, which participants of standard programs face, namely, development contractors and users, accredited test laboratories and certification bodies, state oversight authorities, when woodworking machinery conformity assessment is performed. The suite of safety metrics was suggested for valuation of log-processing equipment and two-level log frames, particularly, on the basis of technical guidelines requirements TG CU 021/2011 “On machinery and equipment safety”, and standards GOST EH 1070, GOST 12.2.026.0, GOST R 5454123 and GOST R 51898. The necessity of standard realization was demonstrated in relevance to obsolete methods of control over equipment (geometric and technology accuracy). GOST 10294 was accepted in 1990 and hasn’t been actualized since that time. That is the reason why it seems impossible to estimate equipment condition, as recommended monitoring facilities are missing
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Description
The article gives results of research of the process of abrasive wear of samples made of Steel 45, U10 and with applied composite surface layer "nickelmulticomponent material with shape memory effect (SME) based on TiNi". For the tests we have chosen TiNiZr, which is in the martensite state and TiNiHfCu, which is in the austenitic state at the test temperature. The formation of the surface layer was carried out by high-speed gas-flame deposition in a protective atmosphere of argon. In the wear test, Al2O3 corundum powder was used as an abrasive. It is shown that the wear rate of samples with a composite surface layer of multicomponent materials with an SME is significantly reduced in comparison with the base, which is explained by reversible phase transformations of the surface layer with an SME. After carrying out the additional surface plastic deformation operation (SPD), the resistance of the laminated composition to abrasion wear is greatly enhanced, due to the reinforcing effect of the SPD. It is recommended for products working in conditions of abrasive wear and high temperatures to use the complex technology of formation of the surface composition "steel-nickel-material with high-temperature EPF", including preparation of the surface of the substrate and the deposited material, VGN in the protective atmosphere of argon, followed by SPD
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Description
The article deals with the reliability of the functioning of the equipment of the power supply substation, and the determination of the probability of uninterrupted supply of electricity to consumers. The following are presented: models of failures of separators, models of short-circuit failures, models of failures of disconnectors. Two statistical series for sudden and gradual failures are singled out. The reliability theory is shown as the main distribution of fail-safe time for sudden failures. The conclusions on the presented models are made and the suggestions on introduction into production are given. According to the presented models, it is possible to judge the reliability of the station's operation, which is necessary for implementing measures to improve the reliability of electricity supply in network companies
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Description
One of the main ways to increase the economic efficiency and environmental safety of the food industry is the introduction of low-waste and non-waste technologies. A vivid example of the technologies of this group is the production of pectin and pectin products from processing residues for food needs of plant objects - various fruits. We have developed a number of ways of obtaining pectin products from unconventional raw materials objects and on their basis we propose technologies for obtaining commodity pectin and pectin extracts from fruit shells of soya, sainfoin, castor oil, tunga and black nuts. For the purpose of operational analytical control of the pectin complex of the listed raw materials, two methods have been proposed, one of which is presented in the article. The presented technique allows determining the amount of pectin by its fractions at any company of pectin production with minimum expenditure of labor and energy. The methodology is implemented as follows. We dry paper folded filters to constant weight. Standardized solutions of protopectin and hydratopectin are prepared. Samples are taken. Then we neutralize the acid solution of protopectin solution and saponize the pectin substances in the analyzed solutions with 40% NaOH solution for 15 minutes. After that, the pectic substances are precipitated with concentrated HCl and the precipitates are filtered. Then the precipitates on the filters are repeatedly washed with cold distilled water to completely remove the chlorine ions. Filters with precipitation are dried to constant weight. The mass fraction of fractions of pectin substances is calculated by formulas for hydratopectin and protopectin alone. The method as a whole makes it possible to improve the accuracy of the results of determining the mass fraction of pectic substances in plant raw materials, to reduce labor and time costs, and to exclude the use of specific equipment
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ORGANIZATIONAL-TECHNOLOGICAL COMPLEX OF WORKS ON UTILIZATION OF AGRICULTURAL MACHINERY
DescriptionNowadays in Russia, there is a problem of utilization of vehicles. A system of recycling of agricultural machinery in Russia is absent. In the article we present an organizational-technological complex of works for utilization of agricultural machinery
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THE USE OF FOKKER-PLANCK EQUATION FOR ANALYTICAL REASONING OF MIXING PROCESS IN THE SCREW MIXER
DescriptionIn the current economic situation, the developing of cattle breeding is taking on special significance. It is well known that the effective way to develop cattle breeding is to increase the total number of efficient livestock. The numerous researches show that the high concentrated fodder premix diet gives the highest effect in increasing animal indicators [1, 2, 3]. Traditionally, the premix is a powder mass, which should be added into the mixture of grain components. Exact following the recipe of prepared fodder allows the maximum usage of forage potential of the concentrate components [4, 5, 6, 7]. In view of the foregoing, food enrichers have special actuality in making high concentrated fodder [8, 9, 10]. The usage of differential Fokker – Planck equation systems allows determining the laws of the mixing process of various granulated products. As a result, it becomes possible to optimize the technological process of the mixerenrichers of concentrated feed so that the resulting mixture of feed would have high quality and technological characteristics. At the same time the duration of sewer-enricher’s work and, as a consequence, the energy intensity of the technological process would accept the minimum possible values [11-16]. The given theoretical approach is based on the consideration of the motion of an individual particle contained in a loose grain mass (phase). Concerning this, it is necessary to accept a number of assumptions about making effort to the feed particles, and the velocity vectors of its initial motion should be taken into account. Taking into account the complexity of the mathematically derived differential equation, its literal analytical solution seems very difficult. Therefore, the first step of the solution is aimed at the obtaining the non-stationary diffusion equation of Fokker - Planck and the boundary conditions for isolating the only one solution. The second step of the solution is implemented by the tabulation at the grid-based points, that is, considering the differential equation not at a random point of the area, but only at the grid nodes. Moreover, it is necessary to apply the approximation of the derivatives at each node. The solution of the equation system allows determining the module of the minimum, average, and maximum values of the phase particle motion in different parts of the mixing chamber, respectively. In connection with this, the aim of the study is to substantiate the processes of motion of various types of granulated products