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The problems of bending-torsional flutter of an aircraft wing are considered. Using equations of motion by the Bubnov-Galerkin method, based on the polynomial approximation of deflections and angle of twist, the problem is reduced to studying a system of ordinary integro-differential equations, where the independent variable is time. The solution of integro-differential equations with singular kernels is found by a numerical method based on quadrature formulas. The influence of physical-mechanical and geometric parameters on the flutter of the aircraft wing was studied. It was established that an account for the viscoelastic properties of the material of thin-walled aircraft structures leads to a 40-60% decrease in the critical flutter velocity. It is shown that an increase in the elongation parameter of an aircraft wing leads to a decrease in the flutter velocity.

As an object of research, the technological process of cutting the roots of the stalks of the pine tree with the soil and placing them on the side together with the spherical disk in the combined aggregate implementation was accepted. In our republic's cotton cultivation field, the world's latest innovations, including minimal, resource-saving, Strip-till, No-till technologies of soil cultivation and drip irrigation methods, are gradually being introduced. Combined aggregates produced abroad and in our country, designed to perform several technological processes at once, are being supported and introduced by cotton growing clusters. We found it necessary to bring a combined aggregate that prepares new sedges and sedges in the fields with sedges. During the movement of the aggregate in the sedge field, the sedges of the sedge are first tilted to the side of the sedge, and the roots are trimmed with soil and placed at the bottom of the sedge. Then, the lower layer of the bush is divided into two parts, it is turned over the stalks laid on the sides, and new bushes are formed in that place. And in the place of existing puss, new furrows are formed. The research was carried out using methods and tools for measuring angles and distances and optimizing parameters using the mathematical planning method of multifactorial experiments. The study's results determined that the diameter of the spherical disk is 510 mm, the radius of curvature is 540 mm, and the installation angles relative to the direction of movement and the vertical should be 30-32° and 20°, respectively. The research results showed that it is possible to perform the technological processes of cutting the layer of the pistachio root with spherical disks and throwing it to the middle of the side.

A review of technologies for sowing non-loose seeds of forage plants shows that seeders and devices that fully meet the requirements of agricultural technology have not yet been created. The available tools do not provide a stable sowing of seeds and their uniform placement in the field, so the distances between the nests are not the same in a row. The authors recommend designing the sampling drum for an innovative universal seeding machine with measuring grooves that ensure the same distance between the seed nests in a row, corresponding to the agrotechnical requirements for seeds. The main requirement when creating a seeder was the need to determine the number of grooves that determine the distance between the nests at different speeds of the unit. In addition, it is also required to ensure that the measuring grooves are filled with the required amount of seeds, which depends on the speed of rotation of the sampling drum. Based on preliminary laboratory experiments and theoretical studies, the optimal parameters of the sampling drum were determined: the diameter of the sampling drum is 100 mm; the speed of rotation of the sampling drum is 8-15 rpm; the number of measuring grooves – 10-12 pieces. These parameters at a speed of MTA -1.44 m/s provide the distance between the seed nests in a row and are 0.5-0.7 m.

The results on photoconductivity effect in the composites consisting of polymer matrix and photosensitive semiconductor phase are presented. The effect of Rd/Rph parameters of photosensitive semiconductor phase on photoconductivity is studied. It is shown that, there is no direct contact between the composites' photoconductivity and the appropriate parameter of its photosensitive semiconductor phase. [ABSTRACT FROM AUTHOR]