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The accuracy of hole machining is significantly affected by factors such as vibrations that inevitably occur during the manufacturing of parts in the technological processing system (TPS). Among them, the vibration of the cutting tool is the most negative phenomenon, since it affects the accuracy and roughness of the treated surfaces, the performance of the machine and the service life of the cutting tool. Cantilever fixing of the cutting tool when boring holes reduces the rigidity of the TPS, which leads to a decrease in their accuracy. Currently, there are no systematic studies of the effect of the vibration stiffness of cantilever fixing tools on the accuracy of the resulting holes. Therefore, the study of the influence of vibrations of the boring cutter on the accuracy of hole processing on numerically controlled machines (CNC) is of great practical importance. When processing parts on modern CNC metal-cutting machines, their performance can be determined by the potentiometer indicators, which allows you to analyze the efficiency of the cutting process, its stability, the amplitude and magnitude of tool vibrations. The article analyzes the influence of vibrations of cutting tools that occur in the TPS during processing on the accuracy of boring holes, using the example of developing a technological route for mechanical processing of a part ‒ a floating pin designed to ensure the alignment of guides in the mold body, using the inventor 3D CAD-CAM system and the «Siemens NX» program. The problem was solved by boring precise holes with a diameter of 30H7 in 40X hardened steel workpieces using a «Sandvik-A20s-STFCR 11-RB1 CoroTurn 107» anti-vibration boring cutter equipped with a replaceable TCMT090204-UM carbide plate. The study was conducted at a modern CNC turning and milling center of the HAAS DS-30y model. Theoretically, it is shown that reducing the vibration of the boring cutter when boring a precise hole is achieved in the following cutting modes: depth t = 0,4 mm, feed s =0,1 mm/rpm and spindle speed n, which changes in the «acceleration‒braking» time interval of 2 seconds, that is, increases from n =1800 rpm to n =2000 rpm and, conversely, allows you to get a 30H7 hole with a cylindrical tolerance of up to 0,02 mm at a length of 100 mm.

The paper investigates the use of CAD-CAM technologies for the design and manufacture of parts on machines with numerical program control (CNC). These technologies allow designing technological routes of processing of surfaces of details of various complexity and making them on modern processing centers with CNC, and their use in the conditions of small-scale, single productions is justified and economically rational. Many operating enterprises in various industries have long been using technological equipment that is morally and physically obsolete. As a rule, wear parts (spare parts) are no longer produced for them. Replacement of obsolete technological equipment in the existing technological schemes of the production process of the enterprise requires significant material and financial costs, and its repair is complicated by the lack of spare parts. Therefore the question of manufacturing by the individual order of the enterprise of a small amount of worn out details for increase of maintainability of the operating technological equipment is actual. The article is devoted to the study of the possibilities of using CAD-CAM software systems «Autodesk Inventor», «ESPRIT» and «Creo Parametric» for the manufacture of custom worn impeller centrifugal electric pump KM 65-50-220, installed in the water treatment system of the food process . The step-by-step sequence of designing and manufacturing of a new improved (modernized) part instead of worn-out, possibilities and advantages of modern CAD-CAM software complexes, technological possibilities of CNC equipment is investigated. It is shown that the use of CAD-CAM systems «Autodesk Inventor», «Esprit» and «Creo Parametric» and a modern machining center Haas UMC-750 with CNC for the manufacture of a new improved design of the impeller of the electric pump, in single production, has significantly reduced technological time, preparation for the manufacture and replacement of worn parts, to improve the quality, reliability, durability and maintainability of the equipment operating at the enterprise.

Wrapping vehicles with a special foil is not only a desire to stand out, change color, advertise your company or mark a special vehicle, but also a from of protecting the paint coating against the negative influence of external factors – e.g. UV radiation, acid rain, road pollution. It is therefore necessary to do it in a professional plant, which will guarantee that the appropriate selection of the applied film will fulfill its protective character. The article presents the issue related to the proteciton of the paint coating.

The modern market makes the competition between economic entities very high. There are a lot of companies with a similar profile and size. Therefore, it is necessary to compete on many levels. Efficiency, both in terms of the use of material resources and human resources, becomes a key aspect. In the case of the use of material resources, the subject is very widely discussed and crucial for most enterprises. Companies try to keep vehicles in use for as long as possible.

A comprehensive study of the statistical distribution of the auto-adhesion lap-shear strength (σ) of amorphous polymer–polymer interfaces using various types of statistical tests and models is a useful approach aimed at a better understanding of the mechanisms of the self-healing interface. In the present work, this approach has been applied, for the first time, to a temperature (T) range below the bulk glass transition temperature (Tgbulk). The interest of this T range consists in a very limited or even frozen translational segmental motion giving little or no chance for adhesion to occur. To clarify this issue, the two identical samples of entangled amorphous polystyrene (PS) with a molecular weight (M) of 105 g/mol or 106 g/mol were kept in contact at T = Tgbulk − 33 °C for one day. The as-self-bonded PS–PS auto-adhesive joints (AJ) of PSs differing in M by an order of magnitude were fractured at ambient temperature, and their σ distributions were analyzed using the Weibull model, the quantile-quantile plots, the normality tests, and the Gaussian distribution. It has been shown that the Weibull model most correctly describes the σ statistical distributions of the two self-bonded PS–PS AJs with different M due to the joints’ brittleness. The values of the Weibull modulus (a statistical parameter) m = 2.40 and 1.89 calculated for PSs with M = 105 and 106 g/mol, respectively, were rather close, indicating that the chain length has a minor effect on the σ data scatter. The Gaussian distribution has been found to be less appropriate for this purpose, though all the normality tests performed have predicted the correctness of the normal distribution for these PS–PS interfaces.

A device for the preparation of a water-filled foamed explosive composition is proposed, which can be used in field conditions for compacting subsidence of unstable soils. Foamed water-filled explosive composition consists of ammonium nitrate, surfactants and water. The method of preparation of foamed explosive composition, which consists in mixing surfactants with water and then with ammonium nitrate mechanically in a low-speed mode without foaming the mixture, applying this suspension under pressure to the object of blasting and metered aeration by ejection mixtures with instantaneous delivery of the foamed explosive composition to the application site. The selection of the component composition of low-density water-filled foamed explosive compositions is proposed, and their physical, technical and dynamic characteristics are given. Dynamic and physico-technical characteristics of low-density foamed explosive compositions were investigated and it was found that the minimum detonation velocity of these explosives in open charges and in charges in the hard shell is less than the minimum detonation velocity of standard ammonite № 6ZHV; the brisance of foamed explosive compositions does not exceed (10–11)*10-3m, which is almost twice less than that of igdanite and three times that of ammonite № 6ZHV; slightly higher pulse pressure rise time to maximum in foamed blast compositions compared to igdanitor; the pressure at the wavefront of foamed explosive compositions is 6–7 times lower than that of ammonite № 6ZHV, respectively, and the velocity of pressure pulse growth is much lower. Such parameters of the pulsesive explosiv of the explosives make it possible to use foamed explosive compositions for uniform compaction of subsidence loess soils at the required power and in the mine clearance of fields.

In the current work, YAGG:Cr3+ nanophosphors were synthesized by the Pechini method and then annealed at different temperatures in the range 800–1300 °C. The structure and morphology of the samples were characterized by X-ray Powder Diffraction (XRPD). The lattice parameters and average crystalline sizes as site occupation by Al3+ and Ga3+ ions were calculated from the Rietveld refinement data. To investigate the effect of crystalline size of the materials on their optical properties: excitation and emission spectra were recorded and analyzed. Finally, the effect of crystalline size on the probability of carrier recombination leading to PersL was determined experimentally with thermoluminescence analyses. The Tmax-Tstop method was applied to determine the trap type and particle size (calcination temperature) effect on their redistribution. A correlation between structural changes and trap redistribution was found. In particular, the extinction of high-temperature TL maximum with increasing annealing temperatures is observed, while low-temperature TL maximum increases and reaches a maximum when the lattice parameter reaches saturation.

The use of thermal and non-thermal atmospheric pressure plasma to solve problems related to agriculture and biomedicine is the focus of this paper. Plasma in thermal equilibrium is used where heat is required. In agriculture, it is used to treat soil and land contaminated by the products of biomass, plastics, post-hospital and pharmaceutical waste combustion, and also by ecological phenomena that have recently been observed, such as droughts, floods and storms, leading to environmental pollution. In biomedical applications, thermal plasma is used in so-called indirect living tissue treatment. The sources of thermal plasma are arcs, plasma torches and microwave plasma reactors. In turn, atmospheric pressure cold (non-thermal) plasma is applied in agriculture and biomedicine where heat adversely affects technological processes. The thermodynamic imbalance of cold plasma makes it suitable for organic syntheses due its low power requirements and the possibility of conducting chemical reactions in gas at relatively low and close to ambient temperatures. It is also suitable in the treatment of living tissues and sterilisation of medical instruments made of materials that are non-resistant to high temperatures. Non-thermal and non-equilibrium discharges at atmospheric pressure that include dielectric barrier discharges (DBDs) and atmospheric pressure plasma jets (APPJs), as well as gliding arc (GAD), can be the source of cold plasma. This paper presents an overview of agriculture and soil protection problems and biomedical and health protection problems that can be solved with the aid of plasma produced with electrical discharges. In particular, agricultural processes related to water, sewage purification with ozone and with advanced oxidation processes, as well as those related to contaminated soil treatment and pest control, are presented. Among the biomedical applications of cold plasma, its antibacterial activity, wound healing, cancer treatment and dental problems are briefly discussed.

High strength fibres of carbon, boron, silicon carbide, tungsten, and other materials are widely used to reinforce metal matrix composite materials. Carbon and boron fibers are usually used to reinforce light alloys based on aluminum and magnesium. Products made from these materials are characterized by high strength and rigidity and can be used for a long time. Technological waste containing such fibres are hazardous to the environment because they are durable and have needle-like and other sharp shapes. Therefore, they must be disposed of with extreme care. A significant incentive for the processing and reuse of waste composites of this type is the relatively high cost of production of the primary fibre and the material as a whole. With the increase in the production of such materials in recent years, the need to recycle composite waste is becoming increasingly important. Three main options for primary processing are used to prepare composites for their subsequent use. They are mechanical, thermal, and chemical grinding technologies. One of the actual and practical areas of processing technology is the method of powder metallurgy. This paper presents the main stages of processing composite materials based on an aluminium matrix and B-W fibres to obtain powder compositions. The results of the studies showing the possibility of the effective use of the obtained crushed waste to manufacture concrete products and the production of cutting and grinding tools are presented.

The gadolinium, gallium, aluminum garnet doped with cerium and co-doped with dysprosium ions were prepared using sol gel method. The SEM images show that after synthesis, the grains are below 100 nm. The powders were ultrasonically mixed with graphene nanoflakes and ceramics were prepared using the high pressure low temperature sintering technique. A series of the ceramics was prepared using different graphene content. The structure of the samples was examined using X-ray diffraction (XRD), scanning electron microscope (SEM) and Raman techniques. The spectroscopic properties were checked using conventional and persistent luminescence spectra measurements. The thermoluminescence glow curves and fading time of persistent luminescence measurements were performed to check how the graphene presence affects the electron traps number and depth. It was found that the addition of graphene improved the thermal conductivity of co-doped samples. This resulted in faster release of deeper traps and an increase in fading of persistent luminescence. The possibility of releasing energy from deep traps without additional stimulation may allow the use in different applications, the matrices and luminescent ions, which so far did not show persistent luminescence at room temperature.

Knowledge of the technical state and construction of the hydraulic and pneumatic control system of Multimedia Hybrid Mobile Stage HMSM allows you to identify hazards and make a risk assessment. The aspects of the algorithmic process of diagnosing pneumatic and hydraulic control systems presented in the work form the basis for the development and implementation of safe solutions in the process of operation. This article describes the methodology for diagnosing HMSM machine hydraulics and industrial pneumatics systems, detailing the factors determining the correctness of maintaining functional fitness. The considerations developed illustrate the complexity of the diagnostic testing design process for condition assessment.

The research is aimed at improving the quality of testing the tribotechnical characteristics of materials on the SMT-1 friction machine. Testing the bearing materials according to the disc-pad model may be incorrect due to sample runouts. The aim of this work was to level out the influence of sample runouts on wear and other tribotechnical characteristics of friction units.

This article considers possible approaches to diagnostics and measurement electrical parameters of supercapacitors. The analysis the results of diagnostics and measurement the parameters of supercapacitors has determined a significant frequency dependence of theirs. The discrepancy between the two-element equivalent circuit of supercapacitors has been established. Diagnostics and control electrical parameters of supercapacitors in the infralow frequency range can be performed by direct conversion methods. In this case, high-precision low-resistance resistors can be used as an exemplary measure. For the diagnostics and design of meters for the electrical parameters of supercapacitors of capacitors, the authors propose an iterative-recursive method for determining the numerical values of the electrical parameters of the equivalent circuit of such objects. The essence of the proposed iterative-recursive method is that at the first stage, the iterative approximation determines the number of n-absorption links, which it is enough to know when developing, manufacturing and operating supercapacitors. Theoretical and experimental studies of the equivalent circuit of supercapacitors show that the equivalent resistance of such capacitors and their capacitance increase with decreasing frequency of the measuring signal, and the nature of these dependences is determined by the number of n-absorption links and the numerical values of the elements of each link.

Mathematical modeling and experimental research represented in this paper is aimed at dynamic force analysis of circuit cards in order to eliminate or reduce dynamic stress and deflection to an acceptable level and to provide strength and reliability in design of circuit card assemblies subjected to vibration. In conditions when viscous friction forces are negligible and viscous friction dampers, such as liquid dampers, cannot be used reduction of oscillation amplitude in critical frequencies was proposed by creating dry friction damper. On the base of mathematical model, the method for reducing dynamic stress and deflection in critical section of circuit cards in resonance conditions has been developed by inserting additional elastic and dissipation joint introduced by dry friction damper. The dry friction damper device is introduced in three variants of design. The effectiveness of dry friction damper is characterized by its elastic and damping characteristics and especially by the stiffness.

This article summarizes the results of research of the work of Russian universal mobile grain cleaning complex. The problem of grain processing and seed preparation can be solved by using a mobile grain cleaning complex, which allows to carry out all types of cleaning (preliminary, primary and secondary). Operational and technological assessment of universal mobile grain cleaning complexes was carried out in the farms of Voronezh region of Russia. The results of the tests showed that the mobile grain cleaning complexes of universal type MGC-30U, MGC-60U and MGC-100U on all operational and technological indicators, quality indicators of technological process and reliability indicators meet the requirements of Russian standards and will find application in small and medium-sized businesses specializing in the cultivation of cereals crops.

As a result of the analysis of the production and status of the fleet of flax harvesting machinery, negative problems with the machines of farms of different types were revealed. The extensive statistical material on the dynamics of changes in flax production indicators has been generalized. Conditional (reference) coefficients have been investigated and refined. The technological need for specialized flax harvesting equipment and its forecast for meeting Russia’s demand for flax fiber have been determined.

The aim of the study is determining the main agricultural technical indicators of the TS-5 gravity-pneumatic cleaner prototype as part of the soybean seed cleaning production line. It was presented the results of research of a evaluation basic indicators of the TS-5 gravitational-pneumatic cleaner in comparison with the basic version of the VIM-3 machine for cleaning soybean seeds. Comparative technical and economic results of the new machine TS - 5 and the basic variant BIM - 3 have been obtained, which allow to conclude that the developed grain cleaning line has shown high technological reliability and resource and energy efficiency.

Production of domestic specialized flax harvesting machinery has almost completely stopped in Russia, and the technical level of available fleet machines is significantly concedes to foreign models in many indicators. The main indicators of the technical level have been predicted based on the analysis of the construction development of flax harvesting machine, main directions and achievements in agricultural machinery construction and related areas of equipment. Application of flax harvesting machine with this technical level will significantly improve energy efficiency in flax production.

The paper represents the mathematical model for diagnostics of solar cell. The research objectives are the problem of determining a solar cell technical condition during its operation. The solar cell diagnostics is based on the mathematical model of solar cells. The single-diode solar cell model is characterized by a slight deviation of the theoretically calculated characteristics from the characteristics of the real solar cell, one of the reasons being the complexity of the accurate measurement of the series resistance. The single-diode solar cell model uses the current and voltage ratio in the form of an implicit function and it cannot be solved directly. For its solution it is necessary to use numerical methods. This is main disadvantage of the single-diode solar cell model. The methodological approach to increasing the reliability of the solar cell diagnostic has been proposed, in terms of multi-parameter the solar cell diagnostic by applying the solar cell impedance model.

In this paper We presented design of analytic dependencies of main geometrics parameters of combine coulter distributer for direct strip sowing of cereals with accounting of pass speed of particle from the distrib-uter.

An algorithm is given for obtaining the formula for the dependence of the deflection of a regular planar truss of an arched type with a suspended lower belt on the number of panels. The cases of uniform loading of the nodes of the upper and lower belts by a vertical load are considered. To generalize a number of solutions obtained in the system of computer mathematics Maple to an arbitrary case, an induction method was applied. For this purpose, for a sequence of coefficients of the particular solutions found, a common term is determined which is a solution of the recurrence equation. The deflection was determined with the help of Mohr's integral, which depends on the forces in the rods. Forces in a statically determinate construction were performed by cutting out nodes from the solution of a system of equations written in a matrix form. The analytical dependence of displacement of the mobile support on the number of panels is found.

Excitation and transmission of vibration inside electronic packages are strongly connected with mechanical characteristics of their enclosure, which are in the objective for the current research aimed at developing methods and means to reduce vibration inside the enclosure case. The main idea of the introduced methods is in creating elastic and dissipative mechanical joints between structural elements, which appear to be the links for vibration transmission, inside and outside of the electronic package enclosure. The effectiveness of developed methods is proved by experimental verification and theoretical foundation.

The modified relay feedback test (MRFT), which was recently proposed as a continuous oscillation method for identification of the process parameters and controller tuning, is used for the design of a robust and an adaptive Proportional-Integral (PI) controller for a gas loop in the oil–gas separator. The gas normally found in the separator is the natural gas (mostly methane) which is contained in crude oil coming from the reservoir. The robust and adaptive PI controllers are developed from analysis of 64 operating modes corresponding to certain ranges of the gas inflow and liquid-level values. It is shown through the developed model and simulations that these operating modes have significant effect on the dynamics of the gas loop. Dynamic properties of the process in each mode are studied through MRFT. The controllers are designed in order to maintain the pressure during the change of the operating conditions. Performance of the designed control system is studied by simulations.

A method for improving the efficiency of construction machinery and vehicles by using the energy-saving engine and transmission oils is proposed. Developed additives give to oils the energy-saving properties. The results of oils tests in engines and transmissions of trucks are given. It is shown the modified oils using reduces the fuel by 7.2% - 8.3%, the efficiency of the transmission increases to 12%.

This article presents the analysis of vertical irregularities and dynamic forces on the switch frogs in operating conditions on the main tracks of Kiev underground railway. For main railways the deterioration problem of tongues, framed rails, switch frogs and as a consequence formation of the character in interaction on the railroad switches is quite widely studied by different scientists, but for conditions of railway underground such researches are practically absent. However, in order to use metal elements of switches rationally and efficiently, the forecast of their service operation and replacement planning, it is necessary to estimate the level of dynamic forces within the most deteriorated elements of switches at different operational stages. This problem is particularly relevant in conditions of financial restriction for track facilities. The studies allowed determining the form, parameters and basic patterns of the irregularities formation in the rolling zone on switch frogs P65 and P50 mark of crossing 1/9 on wooden beams under different operating conditions, which is the basis for determining vertical dynamic forces of interaction within the switch frog subject to setting maximum permissible speeds of movement.

The paper represents theoretical and experimental vibration analysis of electronic packages. The research objectives are bearing parts, such as printed circuit boards, walls of the cases and electronic components, in enclosed electronic packages subjected to vibration during their operation. The theoretical model of the oscillation system representing electronic package installed on the support subjected to vibration is described. Vibration transmission from the shaker to the tested electronic package is explained as the complex problem to solve. The experimental measurement verified significant difference in amplitudes of vibrations transmitted inside the package and incident to. The elements of plate bending theory is used for main boards, case walls and other planar rectangular structures considered as equivalent homogeneous plates, in order to estimate their natural frequencies and forms of free cross oscillations and hence to identify their possible resonances with purpose to avoid them in operation. The significant attention was paid to the experimental research of dynamic characteristics, representing results in form of Chladni figures and amplitude frequency responses.

The paper represents the mathematical model for diagnostics of supercapacitors. The research objectives are the problem of determining a supercapacitor technical condition during its operation. The general reliability of diagnostics is described as the methodological and instrumental reliabilities of diagnostics. The instrumental diagnostic reliability of supercapacitor includes the probabilities of errors of the first and second kind, α and β respectively. The methodological approach to increasing the reliability of supercapacitor diagnostic has been proposed, in terms of multi-parameter supercapacitor diagnostic by applying nonlinear, frequency dependent mathematical models of supercapacitors that take into account nonlinearity, frequency dispersion of parameters and the effect of transient processes in supercapacitors. The more frequencies, operating voltages and currents are applied in the supercapacitor diagnostics, the more methodological reliability of diagnostics will increase in relation to the methodological reliability of supercapacitor diagnostics when only one frequency, voltage and current are applied.

The experience of formation of key students’ competences at higher education civil engineering institutes by means of participation in student’s creative workshops is analyzed in the article. The hierarchical structure of the creative workshop at the NSACU (Sibstrin) is given and the possibilities of completing students’ professional tasks that require a high level of responsibility within the development of electronic learning resources are shown.

The influence of addition of malonic acid, diethylmalonate and acetylacetone to dioctylsebacate on the process of antifriction film formation is studied. It was found that the addition of small amounts of diethylmalonate and acetylacetone contributes to the acceleration of the tribosystem output to the regime. The addition of malonic acid slows down the process of forming an anti-friction film. The results suggest that the coordination iron compounds are involved in the process of antifriction film formation.

The results of the study of the determination of the optimal parameters of the narrowing partitions installed in pneumatic channels with a vertical ascending air flow, intended for seed cleaning, are presented. The installation of the narrowing walls in the pneumatic channels makes it possible to increase the productivity and efficiency of seed cleaning from hardly separated impurities at least 20%, while the optimal ratio of the width of the partitions and the depth of the sections of the air channel varies from 0.3 to 0.5.

In this study, the drag reduction capabilities of compliant coatings made from viscoelastic silicon rubbers are verified experimentally. A series of single-layer compliant coatings of homogeneous materials with constant thicknesses were used. The experiments were performed at different flow velocities in a high-speed water tunnel of Pusan National University. They were accompanied by experimental determination of dynamic viscoelastic properties of the coating materials. Then, for each coating, a dynamic compliance in frequency domain was estimated. Assuming that the coatings interact effectively only with dynamic structures of turbulent boundary layer in a frequency band corresponding to the region about the maximum compliance, promising ranges of flow velocity and coating thickness are outlined. The predicted ranges are compared favourably with the experimental observations in the high-speed water tunnel.

The problem of increasing the power efficiency of internal combustion engines by the method of its tribochemical treatment was considered. Concentrate additives Komol on the base of molybdenum complexes was developed. This concentrate reduces fuel consumption and increases engine power. In this paper the Subaru EJ-25 engine used in aviation and automotive industry was investigated before and after the tribochemical treatment by the bench tests. It’s shown that adding tribochemically active additives into motor oil increases maximal engine power to 10,7% which is 8,7% on comparable engine rotation speeds. The effect was caused by reduced frictional losses as a result of the tribopolymer films formed on friction surfaces.

The article presents theoretical and experimental studies of the patterns of repeatability of seismic waves excited by man-made explosions to assess the earthquake resistance of critical infrastructure objects. The nature of propagation of wave perturbations at the boundary of an elastic half-space during its local excitation is theoretically considered. These studies are based on the integral Laplace and Fourier transformations, the numerical solution of which makes it possible to obtain the values of the repetition periods of elastic wave perturbations at the half-space boundary. On the basis of theoretical studies, the regularity of periods of repetition of perturbations of elastic waves is established, which under certain conditions can create resonant phenomena in protected objects, in particular at a harmonic close to the frequency of natural vibrations of the structure. Confirmation of these results in practice was obtained when critical infrastructure was hit by missile strikes (Kyiv TV tower tower) and in the conditions of blasting operations at quarries, as an example at the Koshchiivske granite quarry of LLC "SIPAN" when assessing the earthquake resistance of critical infrastructure objects, in particular the supports of 330 kW power lines, which are located in the zone of influence of elastic waves. They are based on the formation of patterns of excitation and propagation of elastic waves and determination of their parameters at a distance from the source of excitation (mass explosions at the quarry) using a hardware complex of standard seismic sensors SM-3, a 16-channel analog-to-digital converter (ADC E14-440) of L-Card and a personal computer (PC). Assessment of the influence of the intensity of seismic explosion waves was carried out at the frequency of the amplitude of the maximum speed of vibrations both at the base of the support, which is the norm of seismic safety in accordance with DSTU 4704:2008 and in the structure of the support itself (which is not mandatory in accordance with DSTU 4704:2008). But the presence of harmonics in the explosive spectrum that is close to the natural vibrations of the structure leads to the formation of resonant phenomena in it, which leads to an increase in the speed of vibrations in the structure itself than in the base of the support. Therefore, the maximum speed at a frequency close to its own vibrations or at the base of the support or on its structure is taken as a criterion of seismic safety. Such a wave parameter will best correlate with damage or harm to this structure and was proposed as the norm of its earthquake resistance. The research results obtained in this way prompted the authors to propose a supplement to the current DSTU.

This article examines the effect of crosswind on the deflection of UAV cargo in free fall, taking into account the parameters of air resistance and drag coefficient. The displacement results are obtained graphically through simulation. The diagram of the module for stabilizing the load in free fall and the block diagram of the inertial measurement unit (IMU) are described. An analysis of navigation systems was carried out and an IMU was selected that allows the use of dead reckoning (DR) navigation. The principles of operation of inertial measuring microelectromechanical (MEMS) structures are considered. The principles of using IMU and how to configure MEMS sensor data are discussed. IMU accuracy testing has been carried out. A description of the principles of setting up and using a proportional-integral-derivative (PID) controller to control the angle of the stabilizer wing is presented. 3D simulations were performed for the case with and without the stabilization module. The presented results will be useful to UAV developers.

The article presents the results of works on the analysis of using cutting forces and torque to determine AISI 304 stainless steel milling process state. The research and analyzes were carried out for the determine tool state and the process state itself. The tests were performed using Sandvik milling head, equipped with 345R-1305M-PM 4230 inserts . This study presents and discusses the obtained results determining the resultant value of the minimum and maximum cutting forces and the tool life. The results of observations of the tool's condition were presented.

Turnouts are a barrier in the track for setting the permissible speeds of trains movements on the main tracks, as they have special structural devices for branching traffic from the main track to the side one. Symmetrical switches have a number of advantages over conventional ones: with the same grade as conventional switches, symmetrical switches can provide significantly higher train speeds on the side tracks; with the same radii of transfer curves, symmetrical switches have a shorter length; while maintaining the length of the curve and radius, crosses with a larger angle than in conventional switches can be used. These qualities of single, multilateral symmetrical switches have determined their field of application. On the mainline tracks, symmetrical switches are used in marshalling yards of stations, as well as in main lines when it is necessary to achieve higher speeds on both side lines. Symmetrical switches by their purpose and design have significant differences from the most common conventional switches, and therefore research on these structures is important and relevant. Moreover, very few scientific papers have been devoted to such research, both in our country and abroad. This study reveals the problems of designing the frame rail junction - point, which is the most critical in the operation of a switch and ensuring the safety of trains passing through it.