The authors have studied a wide range of issues, including breeding, seed production, zonal features, and the area suitable for cultivation of Jerusalem artichoke, depending on the purpose, protection measures from diseases and pests, and the technology of cultivation, storage, and processing. As a result of the performed research, the authors have proposed a classification of Jerusalem artichoke varieties divided into two main groups: early (150-170 days) and late (190 days and longer) ones. There have been offered main goals of the industrial use of Jerusalem artichoke cultivated in a mechanized way. To achieve these goals, the authors have developed a methodological framework for researching Jerusalem artichoke in accordance with the requirements of the field experience methodology, the Programme and methodology for the assessment of Jerusalem artichoke varieties in testing nurseries in the framework of the Federal State Programme "Innovative growing of potatoes and Jerusalem artichoke" in 2014-2016 and "Research methods of potato crops" as a most similar crop in the cultivation technology. The methodological framework includes the selection of test sites with account of Jerusalem artichoke’s specific features; monitoring of agrometeorological conditions of experiments; selection of Jerusalem artichoke varieties used as research objects, the conditions and methods for conducting field and laboratory research (phenological observations; the evaluation of biometric indicators; the evaluation of fungal destruction, viral and bacterial diseases and pests; crop testing; the evaluation of yield and quality of tubers and green mass; the determination of table quality of tubers (both raw and boiled ones) and processing material (chips, fries); analyzing of the quality of stored tubers; and the determination of economic and bioenergetic efficiency of Jerusalem artichoke cultivation). There have not been revealed any reliable data on the characteristics of Jerusalem artichoke varieties so far. Therefore, the main provisions of the methodological base for research on Jerusalem artichoke developed by the authors will facilitate a preliminary assessment of Jerusalem artichoke varieties. This will enable farm producers who plan to cultivate Jerusalem artichoke to select proper varieties.

Federal Scientific Agricultural Engineering Centre VIM and Russian Timiryazev State Agrarian University have developed an experimental design of trapezoidal ploughshares with a reversible composite chisel. The authors outline the design of the ploughshare core and the chisel that can be made from a rolling strip of a special cross-section form, with a stiffening rib located on the back surface of the core, extending from the furrow to the field cut in parallel to the share back and blade. The advantages of the new ploughshare design include low manufacturing costs; increased strength and durability; and the availability of the reversible chisel providing for a reversal of the chisel by 180 degrees after the wearing out of one of its cutting edges and thus the prolongation of its operation. The share core and the chisel are made of 30ХГСА steel grade hardened to 45...48 HRC; the share thickness in the stiffener is 12 mm, on the back line - 9 mm, and on the edge line of the blade - 2.5...3 mm. The length of the new share is 580 mm, the width - 125 mm, and the chisel extension - 40 mm, which provides good penetration when plowing hard soils. Experimental shares with reversible chisels were tested in 2015-2016, in the period from August to October in the farm "Krapivinsky" enterprise, Shchyokino district, Tula region. The tested soil had a medium loamy texture, the soil hardness during the testing period was 2.4...3.8 MPa. The experimental share was tested on the 8-base PLN-8-35 plow attached to K-700A tractor. The depth of plowing was 20...25 cm, which is typical for the considered soil-climatic zone. The machine speed was 8.5...10.5 km / h. According to the test results, the average operating time of the experimental plowshares was 85...90 ha/share, including the bit - 69...74 ha/share. All the tested shares were considered suitable for further operation. Field tests of new ploughshares without the use of expensive surfacing blades have shown their advantage over the resource of serial ploughshares of 2.5...3.3 times. The composite ploughshare of a new design can operate for at least one cycle of the annual ploughing season without the replacement of their spare parts.

The paper considers an innovative project for the development of video surveillance systems and management of agrotechnological processes using a time-of-flight camera. The authors have carried out an analysis of modern 3D information technologies for three-dimensional observing agroobjects. The analysis results have shown main opportunities and advantages of using time-of-flight cameras for more accurate positioning and performing agrotechnological operations by mobile and robotic units. The paper provides a mathematical description of the model for the implementation of the time-of-flight technology on photomatrix receivers of optical radiation. The authors have determined areas of wide application of time-of-flight technologies in industry and agriculture and analyzed the main directions of applying time-of-flight cameras in agricultural technologies. Particular attention is paid to the development of specialized search and conversion functions of an unmanned aerial vehicle for effective utilization in agriculture, as the most important task of further development of localized agrotechnologies. The authors have identified tasks of modernizing the functions of an unmanned aerial vehicle to be adapted to the farm production technology, especially, crop production, livestock and nature management, aimed at improving flight-landing, search-recognition and manipulation-robotized characteristics of an unmanned aerial vehicle with the use of 3D technologies. Some basic conclusions on the strategy development for farm production mod-ernization at a new scientific and technical level have been formulated as well.

The authors have made an analysis of the accuracy of earthworks carried out by single-bucket excavators. The accuracy of works carried out by the working mechanism is estimated basing on the mathematical model of the working mechanism with account of possible influence of other parameters in terms of further research. The paper provides the design of a kinematic model of the working mechanism for the domestic caterpillar excavator Chetra EGP-230, outlines its mathematical model intended to estimate the kinematic accuracy of the working mechanism providing for further accuracy calculations with account of dynamic characteristics. To assess the influence accuracy of each hydraulic cylinder of the working mechanism on the position accuracy of the bucket cutting edge, a working area and a service area have been constructed. The range of possible positions of the bucket cutting edge has been calculated with account of errors in the manufacturing of links. When investigating the kinematic chain accuracy of the working mechanism using the classical "maximum-minimum" method, the range of possible positions accounts for 20.6 mm along the vertical coordinate. However, with other combinations of errors in the manufacturing of links, the range of possible positions accounts for 133.5 mm along the vertical coordinate, which is several times higher than the regulated SNiP (Construction Rules and Regulations) value of 50 mm. The authors have studied the influence of errors in the travelling of hydraulic cylinder rods on the position of the bucket cutting edge in the service area. In making a trench up to 2.5 m deep, the position error of the bucket cutting edge of the excavator’s working mechanism, with account of the errors in the travelling of hydraulic cylinder rods, can vary from 10 to 20 mm, and for a deeper trench, the position error of the cutting edge is less than 10 mm. The authors have estimated the geometrical error in the working mechanism displacement and the error in the working mechanism displacement with account of the error in the travelling of rods. Basing on the simulation results, it has been found that the compliance of all links with technical requirements does not guarantee the compliance with the required accuracy of the displacement of the output link of a kinematic chain, which means that insufficient soil amount at the trench base may exceed the required value of 0.05 m, or there is a possibility of increased soil excavation, which could make the development of reclamation systems impossible.

The paper provides an example of the optimization of parameters of a recuperative heat exchanger with account of current economic conditions and specific features of an object. The problem of optimization is exemplified by the fattening section of a pig-breeding farm with a closed production cycle of JSC "Firma "Mortadel". The premises are intended for keeping 280 pig heads for fattening in weight values ranging from 30 to 110 kg. The fattening section is equipped with three recuperators: two UT-6000S models and one UT-3000 model. The total capacity of the recuperators is approximately 15,000 m3/h. Thermo-technical and aerodynamic calculations of the recuperator parameters have been carried out in order to determine the effect of the heat exchange surface area on the efficiency factor of heat utilization and the aerodynamic resistance of the device. The calculated hydraulic resistance has amounted to 127.4 Pa (with a heat exchanger length of 1.71 m). Basing on the calculation results, the author determines requirements for thermal energy for the considered fattening section and the dependence of the payback period and profit on the heat exchanger length (that determines the area and the size). It has been calculated that the payback period of heat recuperators is reduced to the value of the heat recovery efficiency coefficient of 24.18%, and after reaching that value it grows rapidly to 28.25% and then slightly changes. This is explained by the dependence of the hydraulic resistance on the heat exchanger length. When the recuperator length increases, its cost increases too, while its productivity decreases. According to the recoupment criterion, it is advisable to use recuperators with a small coefficient of heat utilization and a length of about 1 m. In order to obtain maximum profit, it has been proved expedient to use recuperators with a longer length of the heat exchanger.

The paper presents a schematic diagram of a farm grain dryer containing a steam compression heat pump, which can be also used for farmhouse heating in winter time. The authors have performed a thermodynamic analysis of the heat pump operation in farming dryers given the temperature of a drying agent at the dryer inlet is 60 Celsius degrees, and the heat pump evaporator is located in the ground with a temperature of 8 Celsius degrees. The boiling point of the refrigerant in the evaporator is 3 Celsius degree, which is 5 Celsius degrees lower than the ground temperature. After compressing the refrigerant up to 11.02 bar in the compressor, its temperature rises to 70 Celsius degrees. During the condensation process, the air passing through the drying chamber (drying agent), is heated to 60...63 Celsius degrees. Freon R600a (CH(CH3)5) has been selected as a refrigerant basing on a comparative analysis of the properties of various refrigerants, environmental safety, an operating temperature range, comparatively low pressure in the compression line, and market availability. A thermodynamic cycle of the heat pump has been constructed as well, which has provided the grounds for calculating the energy parameters of the installation. It has been revealed that the power conversion coefficient is equal to 2.98 and that the use of a heat pump allows saving up to 66.4% of the power used for drying. The thermal analysis of the heat pump operation in a grain dryer working process has proved the efficiency of its application on the farm.

The paper presents some results of optimization calculations for a cotton harvesting and transportation system to be implemented in the Syrian Arab Republic. The authors have determined that with account of the performance of the harvesters used and the harvesting time limitations, two cotton harvesters of the KhMP-1.8 brand (JSC Gomselmash, the Republic of Belarus) are required to get harvest from an area of 100 hectares. Gven a transportation distance of the cotton yield to its temporary storage site of 0.5...1 km, the ratio of machinery means will equal 2: 4 (two combine harvesters per four tractors: Al-Furat E470 tractor with a power capacity of 51.5 kW (the Syrian Arab Republic) with a Palazoglu i2-4 trailer (Turkey). For a transportation distance of 1.5...3 km the ratio will equal 2:5, while for 5 km - 2:6. In case of a transportation distance of 12 km, the ratio between combine harvesters and transportation vehicles amounts to 2:9. For distances of more than 14 km, a diagram of the functional dependence of the number of transportation vehicles calculated for a fixed number of combine harvesters by the criterion of optimality - the minimum of costs from mutual expectation - does not have an extremum even at a ratio of 2:10 and takes the form of an asymptote. In order to obtain an extremum, it is necessary to introduce additional vehicles, which is inexpedient; or make use of other more productive types of vehicles. For example, in most provinces of the Syrian Arab Republic, there are no off-road vehicles capable of travelling across plowed (cultivated) fields.

The paper provides grounds for the use of electrocontact welding of compact materials (wires and ribbons) to make functional coatings on parts of agricultural machines. The authors show a possibility of applying tool-making waste (mechanical and hand saw blades, as well as electric jigsaws) for obtaining functional coatings on cylindrical parts by electrocontact welding (ECW). They have determined a deformation criterion for the weldability of tool-making waste from carbonaceous, alloyed and high-speed steels depending on their physical-and-mechanical properties and the cylindrical part diameter. A criterion reflecting the possibility of welding carbon steel and alloyed steel ribbons of a given thickness to a shaft of a known diameter, which, in particular, can be represented by saw blades, can be checked by the complete tape deformation preceding the destruction. The deformation can be calculated by operating with the physical-and-mechanical properties of the filler material: elongation, as well as the limit and the modulus of elasticity. The paper provides analytical dependencies allowing to calculate the minimum (critical) diameter of the shaft, on which a tape of known dimensions from a material with known physical and mechanical properties can be welded, as exemplified by calculations for some steel grades. It has been established that the critical shaft diameter obtained in the calculation based on dependencies for a 0.65 mm-thick P9 steel ribbon in the as-received condition (after annealing) and in the heat-treated condition (quenching and annealing at 560°C) is 5.8 and 64.4 mm respectively. The authors have experimentally confirmed the proposed calculation formula that allows calculating the cutting length of a compact material by its electrocontact welding on a cylindrical part with the required accuracy.

The paper provides a method of determining the reliability of the electric drive of agricultural machinery basing on the use of marked graphs of the actuator states. Using the mathematical apparatus, the authors consider an electric drive as a dynamic system consisting of n elements and having N states, i.e. as a system with discrete states. The considered system can change its states at any time, so a random process going on inside it can be regarded as a continuous-time process. If continuous-time stochastic process occur in a system with discrete states, the system transitions from state to state may be regarded as being e influenced by some event streams - the flows of failures and restorations of electric drive elements. A random process with discrete states is referred to as the Markov process in case all the probabilistic characteristics of the process depend on the its current state and does not depend on its characteristics in the past (the future depends on the past through the present). If a process is Markovian, all event streams changing the system states are the simplest. Event streams are the simplest, if they meet the requirements of stationary, ordinary nature and the absence of aftereffect. The authors have developed a system of differential equations that describe the numerous set of states and implemented limiting transition to algebraic equations, the solution of which has allowed relatively easy determination of the factors of availability and forced downtime of an electric drive.

Basing on expert and statistical data of distribution networks with a voltage of 10 kV, the authors have studied the elements of electrical equipment failures, their causes and possible solutions. They have also made the reliability analysis of electrical equipment of a 10 kV distribution network. The paper presents a multicriteria methodology for assessing the feasibility of re-equipping 10 kV-overhead lines (OHL) to improve the reliability of electricity supply and the quality of electrical energy. The chosen criteria for the multi-criteria evaluation of using the OHL elements include electricity under-supply, damages from under-supply, voltage deviation, and voltage unevenness. The load growth has also been chosen as the environment uncertainty factor. In order to test the mathematical apparatus of the considered methodology, five overhead transmission lines of 10 kV Podolsk MVS (Moscow High-Voltage Power Network) and Orlovskaya RPS (Power Grid District) have been selected according to five criteria. Basing on the results of assessing the reliability of electricity supply and the quality of electricity, the authors have revealed that the analyzed lines are unreliable, as they feature large voltage losses, high power under-supply and resulting damages. Basing on the analysis of the electrical equipment market in Russia, the authors have selected elements of overhead transmission lines and eight variants of 10 kV-grid configurations with new OHL elements with the purpose of subsequent evaluation and development of the most promising layout.