Vol 32, No 2 (2022)

Introduction. A decrease of damaging loose grains by threshing tools when combing standing plants is an urgent scientific problem. The aim of the research is to develop a technical solution and experimentally confirm the possibility of loose grains pre-separation from the stripped grain heap before it enters the threshing chamber of the combine harvester.
Materials and Methods. The most promising technical solution to minimize the damaging of loose grain is an inclined chamber containing an oblong-hole lattice bottom, under which inclined augers are mounted. The experimental studies had two stages. In the first series of experiments, in laboratory conditions there were determined the optimal sizes of the lattice bottom holes to ensure the maximum passage of loose grains. In the second series of experiments, the degrees of separating and damaging loose grains were evaluated in real field conditions.
Results. According to the results of laboratory studies, it was found that the maximum passage of loose grains through the holes of the lattice bottom is 68.7% with the width of holes 8 mm and their length 160 mm. According to the results of field experiments, it was found that the average passage of loose grains through the holes of the lattice bottom is 90%. At the same time, damaging grains in the inclined chamber did not exceed 0.5%, and in the hopper 1.75%. Damaging grains in the bunker was in the range of 5.25% when the combine operated without pre-separation of the combed grain heap on the lattice bottom of the inclined chamber.
Discussion and Conclusion. Pre-separation of loose grains from the combed heap makes it possible to reduce damaging grains at least three times, and also reduces the power consumed by the drive of the threshing machine by 11–12%.

Introduction. Improvement of the agro-industrial complex involves the creation of new and modernizations of existing working tools and machines. The important conditions for this are the application of modern technologies and ongoing cooperation with the actual manufacturing. The aim of the research is to develop an adaptive centrifugal working tool and improve the quality of mineral fertilization.
Materials and Methods. The adaptive centrifugal working tool was developed and manufactured based on studying the state of the matter and requirements to machines for mineral fertilization. At all stages of the research, there were used computer-aided design and rapid prototyping methods based on additive technologies.
Results. As a result of the use of the presented working tools, the machine operating width has increased by 10.0‒22.5%. Experimental working tools, in comparison with serial ones, allow decreasing uneven distribution of mineral fertilizers by 13.4% due to their redistribution from the central zone to the edges.
Discussion and Conclusion. As a result of experimental studies, the efficiency of the developed adaptive centrifugal working tools has been proved. It allows increasing uniformity of mineral fertilizer distribution and the machine operating width. Modern design methods make it possible to considerably reduce time and costs.

Introduction. The article presents the results of theoretical and experimental studies of threshing and separation processes in the threshing mechanism of the combine harvester with a digital assessment of the fractional composition of the grain-and-straw material being threshed. 
Materials and Methods. The research was carried out on a special stand in the form of a separate unit of the combine threshing mechanism. Grain-and-straw samplers were installed under each threshing section. The mass feed was changed from 1.0 to 6.0 kg/s at a straw ratio of 1:1. 
Results. There was determined the amount of grain and straw passed through the threshing section screen and the rest of grain and straw entering the straw separator depending on their initial amount. For each fraction, there were determined the ratio of straw mass to grain mass, the density and thickness of the grain-and-straw heap layer on the shaking board ahead of the grates and at the beginning of the straw separator keys. The dynamics of grain-and-straw separation was identified by scanning the length of the grains with the determination of the density and compression degree of the grain-and-straw mixture layer in the threshing gap.
Discussion and Conclusion. It was found that in the heap of grain-and-straw passed through a threshing section, the ratio of straw mass to grain mass decreases from 0.46 to 0.27 and density increases from 60.1 to 84.0 kg/m3. In the heap of grain-and-straw that fell on the straw separator, the ratio of the straw mass to the grain mass decreases from 11.2 to 2.0, the density increases within a small range from 21.7 to 26.4 kg/m3. Thickness of the heap layer on the shaking board in front of the cleaning sieves varies in the range 0.25‒10.20 cm, and on the straw walker ‒ 2.2‒19.8 cm 

Introduction. The efficiency and normal work of electrotechnological processes and installations in their operation dynamic modes is characterized by the time of transition from initial to final state, low energy consumption, accuracy in transients and stability of the desired final state. It is proposed, from a single position on the basis of special optimal control, to combine transition and stabilization systems both in terms of determining the control algorithm with minimal energy consumption in the function of the object states and determining the parameters and conditions of movement with minimal deviation from a given trajectory providing the optimal transmission time and energy saving in a stable closed system of an object control.
Materials and Methods. The principle of maximum is used as the main method for finding optimal program control, which for the study of special modes was supplemented with the apparatus of the position generality conditions for nonlinear objects with the coordinate space expansion, taking into account the occurrence of time and optimality criterion. The position generality apparatus is also used to solve energy-saving problems through using linearization in a large source object. Quasi-optimality in terms of transition time and energy consumption is achieved through minimizing energy according to the program motion parameter, which has a contradictory effect on the transition time and control amplitude.
Results. To assess computational difficulties, transition time, energy saving, accuracy and stability, an example of inertial object control according to various criteria is given. The structure of a closed quasi-optimal system with stationary feedback, which is simple in technical implementation, is obtained.
Discussion and Conclusion. The formalization of the approach to the construction of quasi-optimal systems based on the position generality allows it to be used in multi-criteria optimization tasks and computer-aided design systems for energy-intensive industrial, transport, and agricultural electrical installations.

Introduction. One of the main objectives of the food industry is the development of bakery technology for dietary and functional foods. The article gives a complete description of specialized food products. The purpose of this work is to investigate the influence of amaranth and linseed flours on the quality of the gluten-free bakery products. During the study, there was determined the best proportion of gluten-free mixture ingredients for producing a quality product.
Materials and Methods. In the course of the study, there were chosen different formulas of mixtures with the use of amaranth and linseed flours produced by “S.Pudov” company, corn starch by “Trapeza” company, and other ingredients such as yeast, drinking-water, salt and sugar.
Results. To the formula under development there were added 17 grams of corn starch. At the same time, an increase in the gas retention capacity of the dough was noted. The starch served as the best binding component when mixing water with flour.
Discussion and Conclusion. On the basis of the tests performed, data on pH of the dough medium with different proportions of amaranth and linseed flours were obtained. The most acidic medium is in the dough in which the amount of linseed flour is more than the amount of amaranth one. The conducted studies allow assuming that this is caused by the high acidity of linseed flour