The studied factors characterizing each machine are taken with real values of the estimated indicators, for which desirability functions and weight coefficients have been developed using the method of pairwise comparison of estimated indicators of absolute and relative rank places using the percentile function. The dependence of the translation of the estimated indicators of the machine with real values into dimensionless ones for the scale y ^ ’is obtained, according to which the desirability function is calculated, and then the generalized indicator characterizing the complex assessment of the machine. The advantage of a methodological approach to making an objective decision for each machine using the weight coefficients of each estimated indicator is substantiated, which for the problem under consideration vary in the range of 0.06-0.44. According to the maximum value of the generalized indicator of a comprehensive assessment, preference was given to the KShU-12 cultivator.

A modernized Harrington function with three zones of evaluation indicators is proposed: excellent-good-satisfactory for making a decision on choosing the best design of a combine harvester. Harrington’s desirability function is used only in the 0.2 … 0.8 section, in the interval of which the system of j-th estimated indicators with its own units of measurement (operating costs, grain losses, labor costs, energy consumption of the combine harvesting process) is located. The developed desirability scales were used based on economic tests of combines. Dependences are obtained for converting the values of experimental estimated indicators to a dimensionless scale limited by the range of the desirability function 0.2 … 0.8. By the method of paired comparison of the estimated indicators, their rank place, the weight coefficient of each indicator used in calculating the generalized criterion for the comprehensive assessment of each combine harvester was determined. The maximum value of the criterion determines the best design of the combine from the alternative. The values of the D i k criteria for the integrated assessment of combines with and without weight factors (mean geometric value of the criteria) have been analysed. When using the latter, a more significant difference was obtained between the compared designs of combines. Such a comparison can be applied to carry out comparative tests of combines under the same conditions (yield, moisture, weediness, etc.). The purpose of the work is to substantiate, using the example of a group of compared grain harvesters, the best design option using the proposed system of evaluation indicators and generalized criteria for complex evaluation.

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Spraying with herbicides allows you to successfully control weeds. When processing perennial plantations of fruit and berry crops, a certain problem is bypassing the tree trunk. To ensure the quality of soil cultivation in the near-stem areas, a sprayer design with a rotary device was developed. The novelty of this design is confirmed by the patent of the Russian Federation. In the theoretical aspect, a study was made of the uniformity of surface treatment of near-stem zones. As a result, the dependence of the treatment area of the near-stem zones on the diameter of the boles, the distance between them and the angle of rotation of the sprayer's working body was obtained. The uniformity criterion was the maximum area of processing and the minimum area of double processing of the zone near the bole. The optimal initial installation angle of the working body was 58°…60°.

The possibility of using the Harrington desirability function in choosing the most suitable equipment for plasma processing of materials is confirmed. The search for the optimal variant was carried out by calculating the maximum value of the generalized index of desirability. Four types of equipment for plasma cutting of metal are considered. A comparative analysis was carried out on the following indicators: the cost of equipment and technological cutting speeds for low carbon steel, stainless steel, and aluminum. An example of choosing the best equipment from an alternative series is considered. A system of four scales of partial evaluation indicators was used. Graphical and analytical evaluation methods are presented. The value of the generalized desirability index equal to 0.65 corresponds to the optimal variant of equipment for plasma cutting of metal.