Table of contents

PREFACE

The object of the scientific and technical conference "Applied Mechanics and System Dynamics" is the analysis of the current state, trends and prospects for the development of applied mechanics and system dynamics with the aim of improving technology and production and creating new-generation equipment.

The conference addresses topical issues of development and research on the problems of mechanical engineering, strength and dynamics of mechanical systems.

All papers published in this volume of IOP Conference Series: Materials Science and Engineering have been peer reviewed through processes administered by the proceedings Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

Harmonic gear drives are mechanical drives with engaging flexible and circular splines having substantial features that determine the area of their application. These features include large gear ratio in one stage, light weight of a drive relative to the transmitted load, possibility of motion transmission through a sealed wall, a flexible spline and wave generator. Due to the nature of transmission, a flexible spline is permanently deformed by a rotating wave generator. There are alternating stresses arising in it. Alternating stresses in a flexible spline often lead to its fatigue failure. The paper presents the analysis of stresses in the flexible spline, and dependences to determine these stresses are considered. Correction factors are introduced to the considered dependencies. These factors account for the influence of the gear rim on the flexible spline rigidity as well as the influence of certain gear dimensions ratio. These factors were obtained on the basis of experiments. As a result, the analysis of flexible gears load capacity dependence on their dimensions and key differentiator, being the thickness of a flexible spline under the gear rim, was conducted.

The problem of estimating the impact of a particle of a space debris or a micrometeoroid in the solar cell panel of a small spacecraft is considered. Numerical modeling of the impact of particle penetration into the solar cell panel on the dynamics of a small spacecraft and the level of microacceleration of its internal environment have been simulated. As a prototype for numerical modeling, a small spacecraft "Aist-2D" was chosen. The obtained results testify to the significant influence of particle penetration into the solar cell panel on the level of microacceleration of the internal environment of a small spacecraft and the need to take this influence into account when carrying out gravitationally sensitive processes on its board.

Application issues of modern methods and algorithms for optimal control of the process of technological system functioning in dynamic modes ensuring the efficiency of design of technological process of grinding for elastically deformed non-rigid shafts are considered in the paper. Necessary conditions for optimal control of technological system under consideration are investigated using the Pontryagin maximum principle. The influence of changes in moments of cutting forces on parameters of parts handling and transient process time are determined. The values of tensile forces and shaft deflections along the sections in the process of handling are determined. Graphic dependencies characterizing the parameters of processing to control technological system of grinding of non-rigid shafts based on the change in their elastically strained state are presented. Developed mathematical models and optimization of parameters in control of elastically strained state of processed parts ensure an increase in precision of handling and in surface quality of the part by an order of magnitude in comparison with previous developments.

Equations of motion of cotton harvesting machines (CHM) MX-1.8 and hitching system of harvesting devices under vertical oscillations are derived in the paper. On the basis of obtained equations of motion the models and algorithms of optimum control of cotton harvesting machine CHM MX-1.8 are developed. The necessary conditions for optimal control of CHM MX-1.8 motion are investigated by applying the Pontryagin maximum principle. The values of vertical oscillation of CHM MX-1.8 and vertical and torsion oscillations of the hitching system of harvesting machines in the process of motion over the roughness on the headland of cotton fields are determined. The drawbacks of the design of hitching systems of CHM MX-1.8, i.e. the non-uniform distribution of force in the shaft of the swinging mechanism of the hitching are revealed.

The technique for high-temperature sclerometric tests of deposited wearproof metal are developed and various types of heat-resistant alloys are investigated on the basis of iron and nickel, build-up on steel by arc way in helium. The new criterion of an estimation of resistance of metals and alloys is offered to high-temperature deformation.

The possibility of developing the reciprocating machines crosshead drive analogue which main advantage is the reaction absence of the resource-defining translational pair is shown. For achieving the objective, the fundamental postulate of mechanics about the solid body movements addition is used and it is proved that when two identical in module counter rotations around the parallel axes are added, the final translational movement used for changing the power machine working cavity volume is obtained. In the proposed mechanical drive the side reaction eliminating conditions of the resource-defining translational pair are developed.

The worldwide trend of the modern machine building industry is the produced machines power density increase resulting in increasing the operation velocity while the machines mechanical systems joints and rings inertial loading grows and is comparable to the level of the main power flow transformed by the mechanical system. Inertial loading characterizes machines vibration activity. In this regard, machines balancing problem is of particular relevance. The paper provides the mechanical systems balancing technique by installing the counterweight directly in the inertial excitation generation areas.

In article the modification of the Blom's keys preliminary distribution scheme, considering the direction of information streams is suggested. For this modification it is necessary to use function from three variables. Function of formation of key materials will be the asymmetrical. The exponential form of this function which does not increase the volume of key materials is suggested.

The possibility of use the keys preliminary distribution KDP-scheme for mandatory access control realization in the distributed systems with user's hierarchy is considered. The modified keys preliminary distribution algorithm is suggested. It is developed a method for creation of subsets family for solution this task.

To design a discretionary access control policy, a technique is proposed that uses the principle of analogies and is based on both the properties of objects and the properties of subjects. As attributes characterizing these properties, the values of the security attributes of subjects and objects are chosen. The concept of precedent is defined as an access rule explicitly specified by the security administrator. The problem of interpolation of the access matrix is formulated: the security administrator defines a sequence of precedents, it is required to automate the process of filling the remaining cells of the access matrix. On the family of sets of security attributes, a linear order is introduced. The principles of filling the access matrix on the basis of analogy with the dominant precedent in accordance with a given order relation are developed. The analysis of the proposed methodology is performed and its main advantages are revealed.

The article gives a research of surface phase transitions in thin films described by the Ising antiferromagnetic model by Monte Carlo computer simulation. The simulation is carried out at different values of exchange integrals proportion on the surface and in the bulk of the system. The difference between the exchange integral of interaction between the surface spins and the first subsurface layer from the bulk value is also taken into account. It is shown that the phase diagram of the system has a phase where the ordering of spins on the surface of the system occurs at temperatures below the Neel temperature. The difference between the temperatures of the surface phase transition from the temperature of the bulk phase transition is greater than in semi-infinite systems. This difference is explained by the lower influence of bulk ordering on surface ordering.

The article proposes an algorithm for analyzing images with embedded message based on the Koha-Zhao steganographic method. The basic idea is to compare the pairs of coefficients of the discrete cosine transform. For this purpose the dependence of the coefficient difference from the block number is constructed. Numerical differentiation of this dependence allows us to identify the boundaries of the embedded message. After that the analysis of the initial dependence on the allocated interval allows to define the used parameters of Koch-Zhao method. The computer experiment was conducted. It is shown that the proposed algorithm allows to determine exactly the location, size and contents of a hidden message if it is embedded in a continuous sequence of blocks.

The object of the study is an inertial-vacuum dust collector. It is an upgraded version of the inertial-type dust collecting device. This one has the principle of anticyclone. Few articles and books are devoted to the investigation of this type of dust collectors. The purpose of this article is to explain the dependence of changes in the flow part geometry on the degree of ash particles trapping in new type of collector. This question is actual, because equipment becomes obsolete at power plants and it is necessary to find a worthy replacement, or to create a new, qualitatively best ash collecting apparatus. New dust collector allows to catch ash with efficiency of 99%. Inertial-vacuum dust collector (IVDC) was developed jointly with "All-Russia Thermal engineering institute".

The study elucidates the effect exerted by the composition of alumina support with the addition of milled aluminum hydroxide/oxide residues on its textural and strength characteristics and catalytic properties of Pt, Re-containing systems with these supports in n-heptane reforming. The introduction of milled dried residues was shown to increase the support strength. The content of residues in the catalyst can be increased up 100 wt.% without a detrimental effect on the target characteristics of the catalyst performance in reforming. According to experimental data, a high (from 50 to 100 wt.%) content of such residues in the support increases the mechanical strength factor of the support to 30 abs.%, which may be related to remodification of the aluminum hydroxide structure during its "resynthesis". It was demonstrated that 1-2 wt.% of milled residues of the calcined support can be used in the synthesis because this amount only slightly changes the mechanical strength factor and does not affect the catalyst performance. This approach is based on dilution of the initial pseudoboehmite with calcined Al₂O₃ at the peptization step.

The article considers the peculiarities of functioning of proton exchange membrane fuel cells (PEMFC). The mathematical model of the fuel cell, describing its electrical properties and dynamic characteristics is studied. A simulation model of power system with fuel cell as power source in the software environment Matlab/Simulink is developed. The study analyzed the reaction of the PEMFC output characteristics concerning the change in the concentration of oxygen in the oxidizer and the corresponding dependences.

An electric-induction cylindrical electric field strength sensor is considered. The aim of this work is to investigate the interaction of a cylindrical sensor with an inhomogeneous electric field of a linear charge in order to determine the parameters of a sensor that affect its error in an inhomogeneous field. Optimization of the set parameters allows creating sensors with known guaranteed metrological characteristics and having an additional error from the inhomogeneity of the field no more than 3% in the spatial range from 0 to 3R to the source of the field. As a result of the study, the formula for estimating the error of a cylindrical sensor caused by the inhomogeneity of the electric field both from its angular and linear dimensions and from the spatial measurement range was obtained for the first time. The range of application of such high-precision sensors of electric fields is wide. They can be used both in production processes and in various areas of society.

The problem of the approximate calculation of the derivatives of functions having large gradients in the region of an exponential boundary layer is considered. The problem is that the application of the classical formulas of the numerical differentiation on the uniform grids to functions with large gradients leads to significant errors. It is proposed to apply a cubic spline interpolation on a Shishkin grid that condensed in the boundary layer. It is proposed to approximate the derivatives on the basis of the spline differentiation. The error of such approximation is estimated taking into account the uniformity of the estimate with respect to the small parameter.

A large number of basic project parameters of the microsatellite with ammonia propulsion system determines the relevance of the problem of their search by method of random scanning. The aim of the work is to create a methodology of selecting the basic project parameters of the microsatellite using a calculation program adapted to the chosen method of random scanning. The mathematical model for random project parameters selects the optimal mass of the microsatellite with a propulsion system based on complex relationships investigated parameters, providing a solution to the given task microsatellite maneuvering.

The article presents the experimental study results of a nitrogen arcjet thruster prototype for small spacecrafts with a control unit, having thrust up to 38 mN and power consumption up to 160 W. As the result of the experimental studies, the measured values were obtained for the temperature at the nozzle exit and surface and for the pressure in the arcjet thruster chamber. Thanks to the measured parameters, the main characteristics of the arcjet thruster were calculated through gas-dynamic functions of the gas flow. Minimal values for power consumption were determined to ensure stable operation of the arcjet thruster. The validity of the proposed mathematical model was verified by visual detection of active nitrogen formation in a vacuum chamber.

Zirconium, niobium and vanadium are the high costly refractory metals that cause the topicality of economically processing and waste minimization during manufacture the products from such metals. The purpose of this work is to establish the quality of the surface layers after wire electrical discharge machining (WEDM) of Zr, Nb and V. The morphology and crack formation in the surface layers of zirconium, niobium и vanadium was investigated by SEM and profilometry methods. The results of the WEDM regimes influence on morphology, roughness and crack formation in the surface of Zr, Nb and V are presented. It is established that refractory metals are processed more difficult than steel, copper and aluminum alloys, although the morphology of the treated surfaces are practically no different.

The active identification problem of an unstable object is considered. The technique is illustrated on the examples of parameters identification for the first and second order unstable object corresponding to an inverted pendulum, entering an automatic control system with controllers and the example of the first-order unstable object with the controller which parameters are estimated with the use of test sinusoidal signal with a changeable frequency. In the work the use of the specially picked up test signals is offered which significantly simplifies the identification problem in comparison with passive methods. The identification is carried out according to the nomograms built as a result of the processes modeling in the automatic control system at the variation of the object and controller parameters and the test signals impact on system.

The generation of monitoring systems for fiber optical communication lines are examined. The developmental results of pre-crash sections detected both by an optical time domain reflectometer and the Brillouin optical time-domain reflectometer were achieved. The detection subjects of the pre-crash sections under mechanical stresses (strained) or with changed temperature by traces are argued. An advantage of the Brillouin optical time-domain reflectometer for early diagnostics of fiber optical communication lines is obtained.

The investigation deals with the type classification of optical fibers on the reflectogram obtained by the Brillouin reflectometer. The program for determination of optical fiber type by the Brillouin reflectogram is presented. The values of Brillouin frequency shift for some optical fiber types are given. The possibility to classify optical fibers on types and manufacturers using reflectogram is of practical interest.

Results obtained in experimental studies of properties of the Mandelstam – Brillouin scatter in the polarization maintaining single-mode fibers are given in this paper. Experimental data for varieties of such fibers as "Panda" kind are analysed. Traces obtained by BOTDR are presented.

Differences in traces when turning the axis of sections with optical fiber "Panda" at a certain angle are shown.

Analysis of the experiment results revealed important dependence differences of the polarization maintaining fibers from the same dependences of others optical fiber kinds.

The research considers conducting orthogonal experiment (OT) as one of the stages in developing a new discrete element method (DEM) parameters calibration approach. The measured responses in experiment are the parameters obtained by DEM animation processing using machine vision system (MVS). The variable factors in experiment are DEM parameters. A brief overview of an existing calibration approaches given in the article. The choice of OT as a design of experiment tool among other mathematical tools discussed. Experiments conducted using specially developed rig where bulk material's flow captured as DEM animation. DEM animation converted to video and then processed using MVS that allow register the values of such parameters as angle of repose or expiration time (measured responses). The results of the OT show that it is possible to identify four measured responses with the most valuable correlation coefficient. DEM parameters with the biggest influence on the measured responses identified for each of the obtained regression. Obtained results are useful in learning or iterative algorithms development for DEM parameters calibration.

Statistics of emergency situations at pipeline transport facilities indicate that there are problematic issues in the products transportation. The accidents of the past decade were dominated by the theft of these products ("mortem terrorism"), sabotage acts also were recorded. The main direction of research to counteract these threats is aimed at detecting disturbances in the seismic field in the pipeline security zone using a fiber-optic cable (sensor). In the article we propose the structure of the physical protection system of main pipelines to detect and neutralize unauthorized tie-ins into the pipe in order to minimize the level of pipeline protection losses.

The study relates to the important branch of applied mechanics – the theory of vibration isolation of vibroactive objects such as generators, motors, pumps, compressors, fans, pipelines, etc. The design and mathematic model of a prospective support structure using quasi-zero stiffness effect were considered. The support consists of an elastomeric shock reducer as a shell in cross section having a truncated cone shape with inserted cylindrical elastomer spring, specially selected thanks to its elastic characteristics and size, to obtain characteristics with quasi-zero stiffness near support equilibrium. The mathematical model of the support, allowing to select options to reduce the factor of the force transmission to the base in a certain frequency range was obtained. The calculations for the model and charts show the efficiency of vibration isolation for the proposed support.

The work is devoted to the investigation of the influence of control laws on the tuning conditions of the active vibration damper. Active dynamic vibration damper is an additional mass with elasticity and power drive (electrodynamic, electromagnetic) and mounted on the main oscillating mass. Control of the power drive (actuator) is carried out according to information on the movement of the main mass and mass of the absorber. To define the fundamental capabilities of the vibration isolation system with an active dynamic vibration damper, the work of the actuator was assumed to be ideal. The basis of the dynamic model is the differential equations written relative to the equilibrium position of the two-mass system and taking into account the adopted control law of the actuator. It is shown that the use of an active vibration damper makes it possible to significantly expand the frequency range of the minimum value of the force transfer coefficient to the base in comparison with passive dynamic vibration dampers. Based on the results of the study, recommendations were received for the design of vibration isolation systems with an active dynamic vibration damper.

Semiconductor photodetectors are widely used in devices of radio electronics, automation, computer and measuring technology. This paper describes the capability of constructing position sensitive photodetectors and displacement sensors with frequency output signal based on oscillistor effect in semiconductor. The experimental results of the dependence the oscillistor oscillation frequency on radiation intensity and moving of the light beam are described in the paper. The schematic view of the displacement sensor with frequency output based on oscillistor is presented in the paper.

The products made with titanium alloys are widely used in aircraft building, rocket engineering and shipbuilding. In the assembly of these products in these industries fusion welding is used, but its labour intensive and costly process. Reduction of the labour intensity and cost value of joining titanium alloys is possible by using a friction stir welding (FSW) method. In article, FSW distribution in Russia is considered and provides research of weldability of OT-4 (Ti-4Al-1.5Mn analogue) and VT-20 (Ti-6.5Al-1Mo-1V-2Zr analogue) titanium alloys by FSW. The aim of the research is obtaining sound welds of these alloys, designing of a FSW tool, gathering information of a welding process and compiling a list of recommendations for welding. A series of experiments was carried out; the aim of the research for OT-4 was incompletely achieved and for VT-20 was completely achieved. A tool for FSW was developed, data of welding forces and temperatures at different modes are given.

The article reviews one of possible methods of decision-making support in the situation of carrying out an investment expertise. In this article we suppose that the effectiveness of an investment project is evaluated by net present value. This index is considered to be a random variable which can be estimated by an investor as a segment. Main difficulties in decision-making process arise when this segment includes zero value. In order to reduce the rate of uncertainty an investor can decide to carry out an expertise. An original approach of evaluation of expertise utility is reviewed in this article. This approach is applied to a number of investment projects of SHPP construction in Altai Krai. Altai Krai Administration of Industry and Energy was able to reduce expenses of hiring independent experts by 30% as a result of exploitation of review mathematical model.

The article considers the possibility of quantitative determination of the selectivity of multisensor gas analyzers by applying methods of mathematical statistics on an example of a sensor system based on In₂O₃-Ga₂O₃ thin films operating in a mode with several working temperatures and in a dynamic mode with abrupt gas supply. The following methods were investigated: the quadrat sampling, the Thiessen-Voronoi polygons and the k-nearest neighbors. It is shown that the latter is the most attractive for quantitative determination of gas sensor system selectivity. The obtained results are applicable for determining the optimum ratios between the selectivity of the gas sensor system and the costs of achieving that selectivity by making improvements in the construction of sensing unit, a measuring circuit or an output signal processing unit.

The results of the analysis of the influence of various design parameters on the dynamics of the spindle knot of the machine-tool are presented. As a dynamic characteristic, the natural frequencies were chosen. When choosing a dynamic model, the features of spindle knots were taken into account, which do not allow to take full advantage of the rich experience accumulated for rotary systems. The first feature is that modern spindles are massive shafts with areas that are insignificantly different in diameter. This makes it possible to neglect gyroscopic forces when considering the spindle dynamics. The second feature is the asymmetric location of the center of mass relative to the supports. Another feature of the spindle knots is the need to provide high rigidity of the spindle unit in the processing area, whereupon the radial stiffness of the front support is usually several times higher than the rigidity of the back support. Based on a single-mass dynamic model with two degrees of freedom, which performs translational-angular oscillations, the influence of design parameters on the values of natural frequencies was analyzed. As the design parameters, the mass and the moment of inertia of the spindle, the rigidity of the supports, the inter-bearing distance, the position of the center of mass (mass distribution over the front and back supports) were chosen. It was found that the anisotropy of the elastic properties of the spindle supports creates a band of natural frequencies. This complicates the monitoring task, since it requires taking into account the orientation of the hodographs of rigidity and a clear fixation of the direction of control of the oscillations of the spindle. In order to increase the spindle's natural frequencies, an increase in the stiffnesses of the front and back supports, an increase in the distance determining the position of the back support relative to the center of mass, a reduction in the mass of the spindle and the moment of inertia can be envisaged during the design. It is noted that the fastening of the workpiece in the chuck of the machine-tool practically does not affect the values of the natural frequencies. The results of the analysis allow at the design stage to select rational design solutions for the projected machine, create a system for ensuring the predicted dynamic characteristics and organize monitoring of the technical condition of the equipment by a dynamic criterion.

Multidimensional unfolding (statistical deployment, prefscal) is the method for placing simultaneously on the same map a set of observers and a set of targets with fixed distances between each observer and each of the targets. The approximate methods of solving it today suggest that in each of these sets there has at least two elements. In this paper, we propose a method for the exact solution of this problem, when the set of targets is a singleton. Algorithms are easily transferred to the case of only one observer.

The article is devoted to the solution of scientific and technical problem of perfecting the extrusion equipment and technology for processing secondary combined polymeric materials and polymeric mixtures including wastes, by the method of extrusion with use of multi-section screw that allows to manufacture new high-quality products and reduce the environment pollution. A new screw design is proposed consisting of several functional sections. A mathematical model for operation of the extruder with the multi-section screw has been developed to analyse the operation parameters and produce new designs of the extruder screw. Based on the studies of the functional purpose of the extruder zones and features of processing the polymeric mixtures with secondary raw materials, a functional diagram of the screw is proposed. The thickness values of the strips of the polymer mixture components at the outlet of the extruder sections for analysing the mixing capacities have been obtained. It has been established that the extruder with the multi-section screw can be used with effective combination of two stages: mixing and basic processing. With the help of mathematical modelling the diagrams of linear velocities and shear rates for each extruder section have been obtained.

This article presents the results of experimental studies on modifications of the universal combined tillage units UCTU 2.4 with the working parts for deep loosening. The authors performed a modification that allowed to obtain new operational properties of the unit, to increase the wear resistance of working parts, to provide high quality loosening of soil. As a result of research: 1. empirical dependence of agrotechnical and energy parameters of tillage units for deep loosening of soil were found from the speed and depth of tillage; 2. a method for hardening of the working parts was developed by deposition on the base metal abrasion-resistant material by the discontinuous coating in the form of points, without further processing; it provides high wear resistance of working parts. The obtained regularities of changes in agrotechnical indicators and energy parameters can be used in the design and validation of energy-efficient tillage machines for deep loosening of soil with different traction class of a tractor.

The paper considers a concept of feedbacks in the dynamics of mechanical oscillation systems. The authors propose a generalized theory of dynamic damping of oscillations as a process of introducing additional constraints in a basic model that looks like a system with one or two degrees of freedom. This article describes a method for constructing mathematical models and the results of studying the features of the dynamic properties of systems in which dynamic oscillation damping modes can be implemented.

A new method for obtaining high-entropy alloys in the near-surface layer of a metal substrate is proposed. As a metal base, steel containing impurities of chromium, nickel and titanium is used. An ion-plasma method is applied to this substrate with an AlFe043 alloy 15 microns thick. Then the resulting coating was irradiated with a laser. As a source of laser radiation, a neodymium-doped aluminum-garnet laser was used. The duration of the flash of the laser pumping lamps operating in the free-running mode was 2×10-3 s. The energy of the laser pulse was 1 J, the repetition rate of the laser pulses was controlled from 0.1 to 35 Hz. Elemental analysis showed the formation of high-entropic coating with high performance characteristics.

This work examines the influence of tempering regimes on the structure and characteristics of a metal deposited with a high-chromium flux-cored wire of a martensitic class with carbide-boride nitride doping. It is shown that tempering at a temperature of 800 °C provides acceptable for machining values of metal hardness. As a result of the release of the metal with borides, the structure decays with the formation of a ferrite matrix, the amount of eutectics and particles of the strengthening phases decreases, and their microhardness decreases to 358-438 HV for the matrix, to 548-754 HV for the eutectic and to 1071-1174 HV for hardening phases.

This article explores the effect of quenching regimes on the structure and characteristics of a metal deposited by a high-chromium flux-cored wire of a martensitic class with carbide-boride-nitride doping. We established that quenching from a temperature of 1020 °C provides a hardness in the range of 54-58 HRC. It is shown that the hardening is caused by the formation of a martensitic structure, an eutectic composition based on chromium and iron borides, carboboride, carbide and nitride particles for the most part of chromium and titanium with increased microhardness. The hardness of such a metal practically coincides with the hardness of the metal after surfacing.

The article reviews the existing methods for determining the surface energy of solids. Each of the methods described is practically limited to either temperature or values that are experimentally determined with low accuracy. A method is proposed for determining the surface energy of a solid on the basis of the dimensional dependence of its physical properties (magnetic permeability, luminescence intensity, thermal conductivity, etc.). The surface energy of some nitrides, borides and carbides is determined. Its magnitude is much larger than the surface energy of pure metals. The critical radius of nitrides, borides and carbides is calculated, from which the direct Hall-Petch effect is reversed.

Based on the analysis of regulated parameters and control channel a two-level cascade control system of the oil-gas separator was developed. The control system uses data from virtual analyzer of the total calorific value of the fuel gas, the heat content of the emulsion and also the ration of these parameters. Study of the proposed control system was carried on by simulation. The most common scenarios occurring during the operation of the oil-gas separator namely changing the load and other typical perturbing actions were played in order to perform the regulator setting.

The formation of a characteristic space in classification problems can be divided into two stages: the choice of the initial description of objects and the formation of an informative description of objects on the basis of a reduction in the dimension of the space of the original description.

In this paper, the problem of constructing a modified model of recognition operators based on potential functions is considered. The main advantage of the proposed recognition operators is the improvement of accuracy and a significant reduction in the amount of computational operations for the recognition of unknown objects, which makes it possible to apply them in the construction of real-time recognition systems. To test the efficiency of the proposed model, experimental research was carried out to solve the generated model problem and the problem of face recognition.

The paper provides the results of a short circuit impact on wire breakages during wire electrical discharge machining (WEDM) of AISI 9840 steel by the SODICK VZ300L machine. A method of scanning electron microscopy (SEM) is used for debris size, morphology and shape analysis. The carried out investigation led to the conclusion that the most probable reason of the welding bridge formation is due to the non–spherical (conglomerates) particles' presence with a large number of surface irregularities in a dielectric liquid. A classification of debris particles is proposed from the point of view of their dimensions and ability to overlap the spark gap – «effective» and «ineffective» particles.

Methods of chemical analysis, conductometric titration and pH measurement were used to study chemical composition and acid-base properties of cenospheres' surface. It has been established, that at the interaction of cenospheres and water anions of silicon acid, hydrocarbonates, cations of calcium, iron and aluminium are transferred to the solution. Recommendations were made regarding the use of cenospheres as a recyclable material for the production of aluminium and in coagulative water purification.

The paper describes the method for optimization of loading cargo trucks using two-dimensional packing algorithms. The point of this method is to reduce loading cargo problem to two-dimensional packing problem. This problem can be solved by using of various algorithms. There is analysis of several algorithms that are most often used in practical calculations of objects distribution in 2D space in this paper. The object of this study is transport of the metal processing company and its products (cargo). PHP programming language, MySQL database, and Apache web server are used to create client application. The interface developed using HTML5, CSS and javascript.

The paper shows the results of the investigation of the classification of pulse waves based on the cluster analysis of the time parameters of a pulse signal. On the example of the record of the pulse signal of a healthy young man, it was shown a method for classifying pulse waves using the proposed method. It was performed two-cluster, three-cluster and four-cluster classification. After clustering, the data were evaluated in terms of the difference between the separated groups using the nonparametric Kruskel-Wallis. After the classification, it was analyzed the largest group that contains the form of the pulse wave that occurs in the recording most often. The paper shows that the first group of the four-cluster classification contained the most frequently observed type of pulse wave in the recording (46%), and the first group statistically significantly differed from the other two large groups of pulse waves (the second and the third groups, 41%). This classification made it possible to statistically significantly differentiated the largest first group from the following groups by size – the second and the third groups – according to all the attributes, except Er. Pulse waves in the first group will allow estimating correctly the time parameters of the cardiocycle. This classification will make it possible to choose pulse waves with the most accurate parameters in the cardiovascular system for time analysis of the cardiocycle. This investigation will promote creating a decision support system in the sofware for recording and analyzing cardiosignals.

The paper deals with the problem of insufficient resource of wheelsets. Existing solutions to the identified problem are considered. The influence of the geometric characteristics of wheelsets on the operating life of the rolling stock and railway track is shown. The control procedure of tread eccentricity of wheels used in the world practice is given. The theoretical study included calculations of components uncertainty of the known control procedure. The analysis of computational data shows that the largest values possess uncorrected deviation uncertainties of position and form of the datum and measured surfaces evaluated by type A. The control of geometric characteristics of wheelsets is proved to be made with low certainty because the uncertainty of measurement exceeds the permissible uncertainty several-fold. The findings of the theoretical studies confirm the need for further scientific and applied works to ensure the control accuracy of geometric characteristics for wheelsets

The paper deals with the topical issue of quality assurance of technical products according to precise geometrical specifications. The aim of this work is to develop proposals for improving the system of tolerances and fits for linear sizes in the international standard ISO 286-1. The objective of this work is to increase the level of adequacy of the linear size tolerance model to the real dimensional elements of the parts. Two sizes of dimensional element - maximum material size and minimum material size are basic concepts of F. W. Taylor principles. The difference between the size of the maximum material holes (the minimum size) and maximum material size of shaft (maximum size) determines the type of the pair fit. In the ISO system of tolerances the ideal model of a dimensional element without form deviations of the surfaces is applied to linear dimensions. The ideal model is inadequate to the real dimensional element. The rejection of the form deviations resulted in the loss of the dimensional element minimum material size. The tolerance interval limits the upper and lower limits and the deviations of only the maximum material size. Validity inspection of the maximum material size by the upper and lower limit dimensions shall be provided by complete through and no-go gauges. Such monitoring will provide a fit with the required limiting values of clearances and tightness. Form tolerances in the diameter expression that is joined to the dimension tolerance for maximum material size increase the tolerance interval and make the minimum material limit that should be monitored by the no-go two-point gauge. Inconsistencies of the international tolerances system can be eliminated if to move from an inappropriate ideal model of a dimensional element to to the adequate real model considering the form deviation.

In many branches of science, the quasistationary decay rate often is considered to be identical to the inverse mean lifetime of a Brownian particle in a metastable state. We check this presumption numerically modeling the process using the stochastic differential equations (Langevin equations). Our results define the borders of the applicability of this presumption: the ratio of the potential barrier height to the thermal energy is larger than 4. For the smaller values of this ratio, the difference between the mean lifetime and the inverse quasistationary rate achieves several tens percent. This difference depends noticeably upon the strength of dissipation.

Thermal decay of a metastable state is a useful model employed in many branches of natural sciences. The inertia parameter and friction coefficient, as well as the potential energy, might have quite a different scale in the different branches. However, the time evolution of quantities characterizing the decay process (or the Kramers problem) should be the same, e.g. the fission rate. Therefore, it is convenient to have a set of universal parameters for scaling the problem. Performing numerical modeling within the Langevin dynamics, we have managed to find such universal dimensionless parameters.

The article is devoted to the investigation of the surface layer formation accuracy of engineering products by additive methods. The analysis of advantages and disadvantages of layered products synthesis technologies was carried out. It was revealed that, in additive shaping, the exact characteristics of the surface layer differ significantly from the accuracy characteristics of the surface layer of products obtained by the traditional methods. The analysis of domestic and foreign works on the topic of research was carried out. It is revealed that to increase the accuracy characteristics of products obtained by additive methods, it is necessary to realize dynamically the spatial orientation of the working element of the additive installation in the process of shaping. To control the spatial orientation of the working organ of additive equipment, a method is proposed. According to the proposed method, the controlled parameters of the additive installation are calculated on the basis of a 6-coordinate robot. The proposed methodology will allow to calculate the controlled parameters of the process equipment, to provide the required orientation of the working element of the additive installation to reduce the error of shaping (approximation), using 6-axis positioning mechanisms.

The article considers physico-technological aspects of receiving nanostructural topocomposite coatings in terms of the cascade cross effect based on the special cathodic system, making possible ionic-plasma processing simultaneously with the use of three cathodes in a pulse mode. The authors carry out theoretical and experimental researches of forming concentration profiles of element distribution in surface layers of the bilayer "film-base" system. They determine the features of mass transfer processes developing in response to cascade cross effect. It is demonstrated that due to the mutual diffusion of the film and the base elements in the field of the phase boundary in the "film-base" system a transition area is formed. Its dimensions can be associated with the thickness of the nanofilm. The authors give an example of receiving a multilayer nanostructural composition in terms of cascade cross effect.

The development of new territories, as a rule, is complicated due to a preliminary preparation of soil foundations to improve their deformation properties. Modern preference is basically given to mechanical ways, namely to compaction of soil foundations. The development of new and elaboration of the existing models of soil deformation are promising directions in improvement and development of new technologies for mechanical compaction of soil foundations. Theoretical researches were performed to estimate the description adequacy of deformation in a dispersed non-cohesive soil with practical results by the existing models. A sandy soil was used as a sample of disperse non-cohesive soil for which a deformation characteristic was defined in laboratory conditions. The comparative analysis of theoretical and experimental data allowed us to estimate approximation adequacy of results for laboratory studies of a sandy soil deformation for the examined models. The maximum value of a relative error of laboratory data approximation for this model did not exceed 0.145. According to results of conducted studies, a model of a dispersed non-cohesive soil deformation is proposed. Coefficients k₈...k₁₀ of the given relationship are to be calculated according to the results of compression tests of simulated dispersed non-cohesive soil in the operating pressure range.

Two hereditary classes of matroids – the class of matroids of rank doesn't exceeding a fixed positive integer k and the class of matroids of finite rank – are studied by means of the model theory. The problems of axiomatizability of these two classes of matroids as structures and the problems of algorithmic decidability of universal theories of these classes are considered. It is shown that the first class is finitely axiomatizable whereas the second one is nonaxiomatizable. Decidability of the universal theories of the both classes is proved.

The paper presents the results of a study of the production of porous materials based on metal powders, fibers and nets by the method of electric sintering. The method of production porous materials based on tin-phosphor bronze powders of grade BrO10F1, fibers and grids from corrosion-resistant steel is given. The images of appearance and structure of the specimens and the study results of their properties are presented: porosity, permeability coefficient, pore sizes. It has been established that the materials manufactured by electric current sintering have a satisfactory complex of filtering properties and may be used for purification of liquids and gases.

By Scanning electron microscopy, X-ray photoelectron spectroscopy, and X-ray absorption spectroscopy has been studied the effect of an argon ion beam with energy of 5 keV and various fluences (1·10¹⁶ and 5·10¹⁶ ion/cm²) on the morphology, structure, and chemical state of multi-walled carbon nanotubes (MWCNTs). It has been established that irradiation of MWCNTs with argon ions leads to the formation of structural defects and functional oxygen-containing groups of various types (hydroxyl, carboxyl / carbonyl, ether, etc.). It is shown that an increase in the fluence of the beam leads to an increase in the number of functional groups fixed on the walls of the MWCNTs, without changing the types of oxygen-containing groups. It is shown that modification by ion-beam action is promising for increasing the chemical activity and changing the electronic properties of the outer walls of MWCNTs.

With the aim of improving the efficiency of damping oscillations in non-autonomous Duffing system, the elastic element is divided into deformable and accumulating parts; between them four times a period discrete switching is enabled, which consists of the intermittent disconnection and connection parts. The concepts of the spasmodic changes in the initial length of the forged part and the displacement of the protected object static equilibrium state are introduced. Mass transfer between the parts of the elastic element, occurring at the moments of discrete switching, leads to dissipation of mechanical vibrations energy. Using the introduced concepts, characteristics of the positional forces are developed, their harmonic linearization is made, their equivalent stiffness damping and relative attenuation coefficients are found, the influence of amplitude of relative oscillations on them and the parts mass and initial tension ratio are analyzed.

The results of experimental research are provided regarding the operational process of VAZ-21124 petrol engine with the compression ratio of 12.0 on lean air-and-fuel mixtures with various values of heating the air charge at intake, and of the ignition advance angle. In the course of performing the experimental research, the pressure of gases in the engine cylinder was registered, as well as the temperature of the air charge in the intake manifold, the ignition advance angle, and the concentration of toxic components in the exhaust gases. The obtained pressure indicator diagrams were processed using a special program for determining indices of the operating cycle, cycle consumption of fuel and air, air excess factor, and heat release rate. The obtained cycle consumption of fuel and air, as well as the air excess factor were compared to the ones measured experimentally. As a result, possible boundaries of leaning of air-and-fuel mixture were revealed, as well as the values of heating the air charge, and of the ignition advance angle, for intensification of the process of combustion till the knock moment. When the air charge temperature at the intake was raised from 29°C to 112°C;, the ignition advance angle retarded from 35.5 to 15 degrees, and the air excess factor decreased from 1.55 to 1.41 respectively.

The article is devoted to the using of machine learning algorithms for the diagnosis of human diseases on the basis of General blood analysis. The value of this research is in the strategy of the development of the information society in the Russian Federation during 2017 - 2030. The author has developed a model that will allow us to diagnose certain chronic obstructive pulmonary diseases or allergic rhinitis with a sufficient degree of probability. This model will also allow to make a conclusion about the absence of diseases in humans. To implement the methods of machine learning to solve problems in the context of the research topic, the authors obtained impersonal data of the results of a General blood test of more than a thousand people in the city of Bryansk. The results of the study can be the basis for the development of a module which help us to support medical decision-making medical information system.

The paper presents the approach expanding the possible ways of the manipulated object orientation setting, and consequently the robot manipulator end-effector required orientation when maintaining the process equipment through the use of the rotation matrixes 3*3 and one of the Euler angles systems. The algorithm of identifying the complete set of the permitted combinations of angles between the axes of the base coordinate system and the manipulated object one clearly specifying the robot manipulator end-effector desired orientation in the Cartesian coordinates selected space is proposed. Fifty four ways of the orientation defining based on the rotation matrixes 3*3 and six ways on the basis of the Euler angles were obtained. The specified angles combinations make it possible to simplify the integration of the coordinate systems related to the manipulated object and robot manipulator end-effector.

Using the isothermal diffusion method, improved with the consideration of physical and physicochemical properties of the initial binary compounds(InP, CdTe), solid solutions (InP)x(CdTe)1-x, were obtained, certified according to X-ray, submicroscopical and microscopical studies as substitution solid solutions with sphalerite structure. The consistent patterns were revealed in the compositional changes of bulk properties (crystallochemical, structural) which have both gradual and extreme nature.

The constitutional diagrams "property – composition" were plotted. Certain correlations were found between them, which became the principle of practical guidelines for facilitating the search for advanced materials for measuring cells.

for the first time (for given compositions), solid solutions of the GaAs-CdSe system have been obtained, certified on the basis of X-ray and submicroscopical studies as substitution solid solutions with sphalerite and wurtzite structure. The consistent interrelated patterns in changes with composition changes of the system, crystallochemical and structural properties have been revealed: parameters - a, c; crystal lattices interplanar distances - d_hkl; theoretical calculated crystal density - ρ_r; the average number of the most displayed particles in the components – n_av. The pH values of the system components' surfaces isoelectric state have been determined, which fit into the faintly-acid range. On the ground of the set of obtained results, revealed patterns, correlations between them, a conclusion has been made about a possible preliminary certification of the obtained solid solutions of systems similar to the studied one and a possible facilitated way of searching for advanced, promising materials for creating measuring cells for main gases micro impurities, in particular ammonia.

Bulk (crystal-chemical, structural) and surface (chemical composition of the surface, acid-base) properties of solid solutions of the InSb-CdS, CdTe-CdS systems (compared to the initial binary compounds InSb, CdTe, CdS), prepared in the form of fine powders and thin films have been studied in an integrated manner involving up-to-date techniques. Solid solutions are certified as substitution solid solutions with a wurtzite structure.

The consistent patterns have been revealed in the studied properties changes with changes in the systems compositions that have both smooth (subject to Vegard's law) and extreme nature. The predominant influence on them by the first binary components (InSb, CdTe) has been demonstrated and justified.

The acidic sites' nature, strength, concentration have been determined. An increased sensitivity of the system components surfaces (at pHiso<7) to the main gases has been found. The most active of them have been recommended as primary sensors materials for measuring cells for ammonia micro impurities.

Bulk (crystal-chemical, structural, electrophysical) and surface (acid-base) properties of the A^IIIB^V (GaAs, GaSb), A^IIB^VI (ZnSe, ZnTe) type binary compounds, varying in B^V, B^VI elements and substitution solid solutions (GaAs)_x(ZnSe)_1-x, (GaSb)_x(ZnTe)_1-x formed by them have been studied. The acidic sites' natures, strength, concentration have been estimated. The consistent patterns have been established in changes in bulk and acid-base properties with changes in the each particular system components composition; general and differential characteristics in the components "behavior" of the two GaAs-ZnSe and GaSb-ZnTe systems have been revealed. Justification has been given. Reasons have been given on the possibility of predicting the surface activity of such systems' solid solutions. Practical guidelines on the use of their most active representatives in semiconductor gas analysis have been provided.

The testing results of developed tenso-resistive (strain-gauge) sensors printed on 2 types of synthetic nonwovens, using 2 modified types of conductive inks based on carbon nanotubes, graphite, for such flexible high-load and stretchable elements as air-inflated structures, amortization groups and especially soft robotics systems and mechanism are presented. The strong correlation "stretch deformation range – electrical resistance – tenso-sensitivity" for each tested nonwovens was found. The sensors developed on synthetic nonwovens with nanotubes were defined to be most suitable for wider deformation control variety (0-80%) as well as humidity control with dividing on 3 narrow sensitive ranges from 0 to 10, 10-30 and 30-80% elongation. The affect of material density as well as prepress surface thermo-modification and environment conditions deviations was checked. The advantages of these sensors are low-cost and simple operation principle in contrast to other commercially available sensors or known prototypes. All of these sensors were produced using a screen-printing technique.

Methods of functional integration of electromagnetic elements (EME) allow to improve the technical and economic indicators, accelerate the development process, improve manufacturability and reliability, as well as reduce the cost of secondary power sources (SPS). The authors suggest the use of a hybrid EME as an inductive-capacitive converter (ICC), called a "multifunctional integrated electromagnetic component" (MIEC). The authors consider various MIEC designs, in particular a two-section structure. When designing complex MIEC structures, many unresolved issues and tasks arise. The research and development of MIEC and electrotechnical devices based on them is an urgent task. The frequency and energy characteristics of the ICC are analyzed on the basis of a two-section MIEC in this article. An experimental confirmation of the adequacy of the developed mathematical model for calculating and constructing the frequency characteristics of MIEC and estimating the stabilization properties of ICCs for various design versions of MIEC is carried out. It is obtained that in the manufacture of two identical MIECs with identical electrical parameters placed on separate frames with a common magnetic circuit (with the same number of turns of each electrode, active and inductive resistance of MIEC) this circuit solution of ICC has a higher voltage gain.

The article deals with a problem of minimization of levels of professional risks while servicing truck tires and wheels. In the process of removal of a truck wheel a worker can sustain a serious or fatal injury caused by the explosion of an inflated truck tire. The explosion of an inflated truck tire can result in affecting of complementary offloading's on clamps cast spoke wheel. The mathematical model description of move of a disk wheel and values of reactive forces arising from the explosion of an inflated truck tire are presented. The equations of move of a disk wheel at its removal under the influence of reactive forces are solved. Results of numerical modelling of stresses arising on clamps cast spoke wheel during the explosion of the inflated truck tire are presented. The maximum normal stress arises in the stub basis can lead to free move of wheel and in a place of contact of a disk of a wheel high tangential stresses to destruction of a nut is positioned.

Investigations of the effect of the moldboard angle, the earth-moving machine of the motor grader type, on the angle of the cross slope of the formed earth surface was carried out. It is established, that the slope in the cross direction of the surface being graded, depends on the angles of installation of the moldboard blade element. The slope of the surface being graded, is not affected by the dimensions of the moldboard and the construction of the earth-moving machine. Analytical and graphical functional dependences of the angle of inclination of the moldboard blade element to the horizontal plane are obtained, which are necessary to ensure a given angle of the cross slope of the surface being graded. The results of the research can be applied in the field of development and tuning of on-board systems for indicating and controlling the operating modes of an earth-moving machine.

The method of complete analytical solution of the problem of cargo movement on a pendulum suspension of constant length on a set trajectory in a flat statement is developed. To set the required trajectory as a time dependence of the linear horizontal coordinate of the cargo in a limited time interval, two-point Hermite polynomials are used. When a certain amount of the first derivatives of the linear coordinate of the load is equal to zero in the horizontal direction at the ends of the segment, a vertical arrangement of the crane's cargo rope is provided at the boundary points and there are no uncontrolled angular swings of the cargo rope during the entire movement. Analytical dependences of the horizontal coordinate of the cargo, its first and second derivatives, the angle of the deviation of the cargo rope from the vertical, its first and second derivatives, as well as the horizontal coordinate of the upper point of the load suspension, its first and second derivatives from the time of displacement are obtained. Scope of the method – automatic control systems for the movement of bridge and gantry cranes, as well as modelling of crane work processes. The application area of the procedure is limited to the small angles of deflection of the cargo rope of the bridge crane from the gravitational vertical. The method opens the possibility of rapid synthesis of the optimal trajectory of the suspension point, which accurately provides the required trajectory of cargo movement. There is no need to use a comparatively complex mathematical apparatus of the theory of optimal management, or resource-intensive algorithms of multidimensional and iterative optimization.

The article describes the approach to the modernization of information systems based on Web-technologies with the aim to improve their indexing by search engines, to increase the interconnection of such systems content, improving GUI in terms of interaction with social services and networks. The most important metrics for statistical data collection systems are described. The set of criteria to evaluate the work of SEO specialists is given.

The theory of a flexible dimensional-dependent plate of the network structure is constructed in this paper. The plate is considered as a Cosserat continuum with constrained particle rotation (pseudocontinuum). The lattice structure is constructed according to the theory of Pshenichnov G.I. The equilibrium equations for the plate element and the boundary conditions are obtained from the Lagrange variation principle on the basis of Kirchhoff's kinematic hypotheses. The geometric nonlinearity is taken into account by the model of Theodor von Karman. By the Bubnov-Galerkin method an analytical solution was found for a square hinge supported by the ends reticulated plate, consisting of two families of ribs under normal load.

Hydrocarbon processing plants (HPP) are the key elements of the fuel and energy complex of the Russian Federation. At the same time, they are characterized by the increased energy consumption of the production and have a negative impact on the environment. The energy and resource saving technologies implementation necessity at the industry enterprises is declared at the state level and is a complex scientific problem. HPP energy efficiency improvement high potential is concentrated in the fuel systems modernization. The paper presents the fuel system analysis results, besides the fuel system relationships with the facility process system, its energy complex and external power supply systems were established. The energy consumption mix analysis of the HPP main production facilities for all types of fuel was carried out. Internal generation hydrocarbon fuel, namely refinery gas and mazut were established to be mainly applied as fuel. Refinery fuel gas of the internal generation was found out to have a variable blend composition. HPP fuel efficiency thermodynamic analysis was conducted to determine the fuel exergy absolute and specific consumption. Moreover, the HPP fuel systems efficiency improvement most promising areas were identified. On the basis of the conducted studies, a block scheme of the internal power supply source combined with the combustible secondary energy resources (SER) utilization system was developed. The feasibility study of the proposed scheme application expediency was conducted.

In the article, using the example of the walking excavator ESh 20.90, the results of studies on the choice of design parameters of the traction mechanism ensuring the reducing of dynamic loads, based on solving the inverse dynamic problem according to a given type of oscillatory movements of the actuator and using the theory of mechanical circuits are presented. By numerical simulation of the electromechanical system it is shown that the introduction of an additional elastic-damping device in the kinematic scheme of the excavator traction mechanism will allow to reduce the dynamic loads and the duration of their action on the traction mechanism in the start-up and load-step modes and significantly increase the logarithmic decrement of the elastic oscillation.

The article considers the results of vanadium dioxide VO_2±X study (within the homogeneity range) and solid solutions V_1-XFe_XO₂, obtained by X-ray diffraction and the Faraday method. The temperature dependences of the magnetic susceptibility samples are presented, and it follows that dependence χ (T) character in the temperature range from 100 К up to 250 К is close to Curie law for paramagnetic in the area of the phase transition at temperature Tmp ∼ 340 К, and there is an abrupt change in χ. It is considered that the magnetic properties of vanadium dioxide vary both with the change in the oxygen content in the samples and with the doping of vanadium dioxide with iron. It was established that vanadium dioxide VO_2±X and solid solutions V_1-XFe_XO₂ are paramagnetic both in the semiconductor and metallic states.

Results of experimental researches of carbon steels plasticity changes in steel grades 10, 35 and U8A, depending on deformation temperature are provided to vicinities of critical points Ac₁ and Ac₃. Change of plasticity in the studied materials analyzed on values of an aspect ratio and strength. It is revealed that the aspect ratio of these steels as the characteristic of plasticity raises with increase in temperature, reaches a maximum, higher than temperature of critical point decreases and increases with the subsequent increase of temperature. In steels with small carbon content the main contribution to increase in plasticity is made by a condition of pretransformation near a point of phase transition Ac₃. In eutectoid steel grade U8A the main increase of plasticity is provided with a condition of pretransformation near eutectoid phase transition in a point Ac_1. In steel grade 35 on curve dependence of plasticity on temperature two extremum corresponding to a condition of pretransformation before points Ac₁ and Ac₃ are observed. It is established that in all three steel grades of the studied carbon steels in a condition of pretransformation plasticity is higher, than in an austenitic state. The revealed patterns and the received mathematical dependences describing changes of plasticity at phase transformations of carbon steels give the chance of practical application of the found plasticity resource when processing by pressure of different classes of steels. Processing in this case can be made at lower temperatures and forces of deformation that will allow reducing risk of emergence of scale, to increase processing productivity. The received results can be used when developing power- and resource-saving technologies of processing by pressure of carbon steels.

The article considers the issues of improvement of active control devices (ACD) of the sizes of products with intermittent surface in the direction of increase of accuracy of measurements, expansion of functionality and simplification of their design. The composition and principle of action ACD with telescopic guides on the basis of console pinned corundum rod, increasing the rigidity of the design, transmitting optical signals and changes's pressure from the compressor for control movement of the measuring tip. It is proposed to use magnetic fluid to fill the gaps of these telescopic guides.

It is shown that the value of the specific energy of the contacting W_cont corundum tip with product ledges, defined by the calculation path, corresponds to the quasi plasticity mode of the material and does not lead to fragile destruction, providing ≈ 40 times the stock strength. The first results of experimental working out of the pilot model of this ACD by use telescopic guides on the basis of console pinned steel rod are presented.

The article discusses questions of composition, principle of operation, two main operation modes and interrelations of the main parameters of the developed electro-jet microscope, which implements a new way of visualizing the product surface for active control of its irregularities are discussed in the article. At the heart of the device is the use of electro-jet technology to control the trajectory of the coherent monodisperse flow of transparent liquid droplets, incl. which is a coolant, serving as a focusing lens for the transmission of an optical image as in a conventional solid-state microscope. The image is recorded impulsively. One- and two-drop operation modes of the electro-drop jet microscope are presented: on the basis of a single moving drop and in the form of a combination of an ellipsoid drop oblate after impact on the surface of the article and a moving drop approaching it.

The problem of creation and applying of materials with determined properties necessitates of complication of materials mathematical models, which are predicting their behavior under conditions of initial stress and high temperatures and are able to take into account both the complex structure of materials and the presence of coupled elastic and temperature fields. In the framework of the linearized theory of thermo-elastic waves propagation coupled boundary dynamic problem of harmonic vibrations of thermoelastic semi-infinite solid is investigated. Vibrations are induced by distributed in a region on the body surface of the oscillating heat flow. Outside this region, the upper bound is insulated. The surface is free of mechanical stress. We constructed the solution of the contact problem analytically. The Greens function of the problem poles are obtained and shown graphically. The effect of initial stress and pre-heating on the dispersion curves are investigated.

The article presents the results of investigation of the small module gear wheels manufacture from steel 35 by using wire EDM on the SODICK VZ300L machine. The purpose of this investigation is to increase the accuracy of the produced gear wheels, the task of this work is studying the accuracy of gears manufactured by the control program, while the wheel contour is drawn from arcs constructed with CAD-system with a large number of reference points. Contact and non-contact methods are used to study the geometrical parameters of the produced gears. Contact measurements were carried out on the Lapik coordinate measuring machine KIM-750, contactless measurements on a tool microscope Walter UHL VMM 150. The conducted study led to the conclusion that the proposed method allows obtaining high-precision wheels and there is a tendency to enlargement this accuracy by increasing the number approximating elements in the contour construction of the produced gear wheel.

One of the ways of increasing accuracy of printed electronics elements produced with the use of stencil screen printing is the use of doctor rollers with a resilient cellular packing. The amount of paste in cells is regulated by a metering doctor blade and depends on the hydrodynamic pressure in paste. This paper presents a method of determining the thickness of the paste layer with a viscosity of 400 Pa·s on a print. The experiments showed that the pressure in the layer of paste in front of a moving doctor roller is 30000-130000 Pa. For the preliminary gap between the doctor blade and doctor roller of 0-0.3 mm, thickness of the paste layer on the print is 8-12.9 µm.

The mathematical model of shock loading of a pipe, in which on an inner surface impulses of radial tension of pressure are instantly put, is offered. These impulses lead to distribution in a pipe as the falling waves of tension of compression, and an interference of the falling and back waves of tension, which are formed, on a free surface. The system of differential equations together with boundary and entry conditions for the description of the intense deformed condition of material of a pipe, and considering process of distribution in it radial waves of pressure is offered. The method of characteristics is applied to obtaining the decision of this system. The method is developed and the equations for definition the intense deformed condition of material of a pipe of the pipeline are received at a hydraulic shock. It is established that the interference of these waves has essential quantitative shock on nature of voltage variation and, as a result, can lead to possible destruction of the pipeline. It is shown that when loading a pipe shock pressure, its stress-strain state can be considered settled approximately after triple run by a wave of tension in the direction from loaded to a free surface and back.

The stages for cognitive modeling designed by the authors to build and analyze a cognitive model are presented in the article. The theory of graphs and evaluation methods are used to formalize a simplistic cognitive model visualized as a cognitive map. Alignment of evaluations is provided using mathematical statistics.

The simulation experiment to support the model is developed with both Microsoft Excel and the original software program worked out by the authors using the algorithm based on a mathematical model represented by finite and differential equations. Auctorial original software to analyze the cognitive model is necessary in order to substitute the imported computer programs. Comparing both outcomes reveals that the developed software performs calculations correctly. The results obtained with both software are given to support the experiment.

The article considers the main functional requirements and software and technical solutions for the implementation of the automation system for monitoring technological objects. It presents a solution to improve the efficiency of the automated system for monitoring technological gas transporting objects based on the research and the experimental data. A model of building a fault-tolerant automation system in the industry that allows you to monitor the performance of the main elements of the automated monitoring systems.

Feature selection is known as a very useful technique in machine learning practice as it may result in the development of more straightforward models with better accuracy. Traditionally, feature selection is considered as a single-objective problem, however, it can be easily formulated in terms of two objectives. The solving of such problems requires the application of appropriate multi-objective optimization methods that do not always offer equally good solutions even under the same conditions. This paper focuses on the development of a metaheuristic optimization approach for bi-objective feature selection problem in two-class classification. We consider the solving of this problem in terms of minimization of both misclassification error and feature subset size. For solving the considered problem, an adaptation of the Multi-Objective Adaptive Memory Programming (MOAMP) metaheuristic based on the tabu search strategy is proposed. Our MOAMP adaption has been utilized to obtain the sets of most relevant features for two real classification problems with two classes. Finally, using popular Pareto front quality indicators, the obtained results have been compared with the sets of non-dominated solutions derived by the well-known NSGA2 algorithm. The conducted research allows concluding about the ability of the MOAMP adaptation to get a better efficient frontier for the same number of objective function calls.

The paper presents solutions of the direct and inverse tasks of geometric optics on a plane: given a carrier of a bundle of rays and a reflector (mirror curve), the carrier of a bundle of reflected rays is determined; given carriers of bundles of rays, their common reflector is determined. The method of determining the reflector for pairs consisting of carriers of central, diffused or parallel bundles of lines modeling various emitters or receivers of illumination is based on optical properties of cyclographic projection of curved line.

The atmospheric descent of a spacecraft with a small geometric asymmetry is considered. A quasi-linear dynamic system describes the motion of a spacecraft relative to the center of mass. The aim of the paper is to obtain the approximate optimal angular velocity control law, taking into account the change of the geometric asymmetry. We apply the method of dynamic programming and the non-resonant scheme of the averaging method for the synthesis of the optimal control law. Numerical results confirm the effectiveness of the obtained approximate law for optimal control of the angular velocity with respect to the problem of descent of the spacecraft with a small geometric asymmetry in the Martian atmosphere.

The types of biofuels used in internal combustion engines are considered. The advantages of using gaseous biofuels are shown. The organization of the diesel engine working process on biogas with the ignition dose of rapeseed oil methyl ester is presented. The results of experimental studies of a diesel engine operating on biogas with the ignition dose of methyl ester of rapeseed oil are presented. The possibility of improving the environmental performance of the diesel engine with such organization of its working process is shown.

The paper investigates the annihilation processes between the molecules of rose bengal dye, a donor of triplet energy, and the molecules of the aromatic hydrocarbon anthracene, an acceptor of triplet energy, adsorbed on the silica surface SiO₂ in the temperature range 218 ... 293, K. The rate constants of homo- and heteroannihilation of luminophore molecules in a wide temperature range are determined. It is established that the energy transfer processes in the initial (after photoexcitation) periods of phosphorescence decay are described by Inokuti-Hirayama equations, and the kinetics of phosphorescence decay becomes similar to the fractal one in the medium-time and long-time periods.

Non-Orthogonal Frequency Division Multiplexing (N-OFDM) remains to be a promising digital modulation technique for high-data-rate wireless transmission. This research is focused on the efficiency analysis of a technique for data frames time synchronization in a white noise communication channel and on an optimal demodulation in the N-OFDM system. N-OFDM signals are generated using the Hartley transform and the Cauchy method is applied for the evaluation signal amplitude the demodulation procedure. The peak-to-average power ratio (PAPR) for different frequency spacing between N-OFDM subcarriers is analyzed. As a result, the mathematical expression for the subcarrier initial phase over subcarrier frequency is derived that allows calculating initial phase with the minimum of PAPR. The paper contains experimental results confirming the operability of the proposed time synchronization scheme. In the experiment, bit error rate estimation was performed for various spacing frequencies and signal-to-noise ratio in the range from 0 to 25 dB. The experimental results have shown the opportunity of PAPR reduction through the calculation of reasonable initial phase for each subcarrier. The experiment was based on simulation in MATLAB with the use of a sound card of a personal computer.

This article addresses problems of optimization of power specifications and efficiency improvement of electric drives for quarter-turn valves. What is proposed is a quad-link transmission mechanism having a variable transmission function matched with the ball valve torque specification. Using the elaborated and proven methodology of comparing technical solutions at the design phase, based on the qualitative-quantitative assessment and analysis of engineering and manufacturing parameters, two alternatives of the transmission mechanism construction were compared. Advantages and disadvantages of the proposed technical solutions are being analyzed. Preferable embodiments of the high-efficiency quarter-turn valve electric drive with the proposed transmission mechanism were determined.

The issues of increasing flexibility of process lines due to optimizing the mechanical components of cyber-physical production systems in which small-size industrial robots are used have been encompassed. The approach to expanding operation areas for industrial robot manipulators is one of the most difficult ones in practical implementation, but it has a number of advantages in terms of increasing the technological flexibility of robotized lines. Expanding the operation area for a manipulator is possible through several ways, for instance, by increasing the linear sizes of links, by giving an additional degree of freedom – through installation of a self-propelled base or mounting of such manipulator on a railtrack. However, the studied methods have considerable deficiencies one of which is a high cost of such solutions. The method to expand the manipulator operation area was offered, which provides for relocation of the manipulator to fixed base surfaces. The requirements for the manipulator relocation mechanisms have been analyzed. A specific embodiment of the mechanical part of the relocation mechanism drive adjusted for the performance features, in particular, for ensuring force pressing to the base surfaces for their reliable coupling, has been suggested.

The article compares the planning systems of the enterprise, determines their opportunities to use simulation for the process of distribution of production orders. A comparative review of the methods used in production planning systems and the multi-agent approach in solving the problem of the allocation of production orders is carried out. The possibility of approaches in cases when it is impossible to perform production tasks within the established time frame is considered, as well as to effectively load the available capacities of the units. In case it is not possible to produce the necessary quantity to distribute the part to another, similar to the type of equipment used, but different from it by the quantity and production capacity of the unit. Transmission must be carried out under the condition of sufficient capacity in the subdivision. The results of theoretical and experimental studies are presented. In the process of work, we used the BPsim. MAS dynamic modeling system. An automated system with the possibility of using simulation for the allocation of production orders is considered.

The technology improvement of conical springs manufacturing is considered in the work. It is proposed to change of the standard die scheme for the production of conical springs. As an improvement of the stamp, an elastic medium is used in the forming space of the stamping tool. Such a change in the die tool lead to improvement of the conical springs operational features and a reduction in their costs. The technique for estimating of a conical spring operational properties has been proposed. The technique was developed on the basis of mathematical modeling of the compression process in the operation of a spring. It was revealed that the existing technology of making conical springs promotes the formation of sharp edges. Improving of the spring section shape and form it with a curvilinear generatrix is proposed to eliminate the additional manufacturing stage of their dulling and for the increase in the endurance of the conical spring. To study the stamping process with using an elastic medium, a mathematical simulation of the conical springs stamping with an elastic medium was conducted. The dependences of the stamping force on the punch displacement are obtained. The experimental design of the tool for the conical springs stamping with the use of an elastic medium is designed. Experimental stamping of blanks with optimal parameters was carried out.

Protection of acoustic information is one of the most important tasks in the overall complex of measures to ensure information security of the technical protection object. Important stages of the acoustic channel protection are the assessment and periodic monitoring of the insulation properties of enclosing structures. The article presents the developed program, which provides the possibility of preliminary estimation of the premises with the use of additional equipment. The main algorithms of software operation are considered. The analyses of results and estimated accuracy of developed software are presented.

The paper is devoted to the problem of generation for periodic mechanical force and construction of its generator. The problem is vital for numerous fields of technics dealing with transmission of vibration energy to mechanical objects. The problem was solved in the framework of classical mechanics for calculation of inertia forces in rotational system of special type. New method of generation of periodic mechanical oscillations was acquired as well as the construction of the new type of vibration generator. The force being generated by the device is a result of inertial forces which occur during special planetary motion of unbalanced massive bodies on the rotating shaft with chain gear. Analytic and graphic representations for dependences of periodic force on time are presented in the article

The hydroelastic oscillations problem of the sandwich beam resting on elastic foundation and interacting with the pulsating fluid layer was investigated. The three-layered beam with an incompressible lightweight filler was considered. The broken normal hypothesis for the three-layered beam and the model of viscous incompressible fluid, as well as Winkler model for elastic foundation, was chosen to study hyroelastic problem. A mathematical model of the considered mechanical system consists of dynamic equations of the three-layered beam with incompressible lightweight filler and the Navier-Stokes equations with continuity equation for the pulsating viscous fluid layer. The no-slip conditions and pressure coincidence at the edges with the given pressure into edges cavities were selected as boundary ones. The plane problem of hydroelastic beam bending oscillations for the regime of steady harmonic ones were considered. The solution of the hydroelastic problem was carried out by the perturbations method using proposed small parameters of the hydroelastic problem. As a result, the laws of three-layered beam elastic deflections and the hydrodynamic parameters of pulsating viscous fluid layer were obtained.

The development of the agricultural sector for the production of promising varieties of potatoes is limited to viral infections, as well as to the use of poor quality seed material. The most effective way of producing elite potatoes seeds is aeroponic system of potato seeds breeding. To improve the installations performance and reduce the cost, it is proposed to use the gate control unit for dispensing nutrient solution to the root system of potato plants. In the course of research, it is possible to adjust the designed control unit for filing a nutrient solution at certain intervals and automate industrial aeroponic installations operating at large areas.

The article presents the fundamental principles of mixing condensers calculation. The design calculation flow chart of apparatuses of this type is proposed. A good convergence of the droplet motion hydromechanics with the other authors works results is identified. The operating conditions calculation results of the contact condenser as a part of the chemical energy unit with hydrocarbon raw material partial oxidation showed that mass transfer impact on the heat exchange is quite significant (the Gukhman criterion is 0.0076), which affects the high process intensity (heat transfer coefficient is ∼179 W/(m²·°C)). However, as expected, the device is characterized by the low resistance of ∼6 Pa.

Considered the methods for solving the problem of the Kolmogorov-Fisher type diffusion reaction in the two-dimensional case. Obtained invariant properties of solutions and a two-sided estimate of the solution of the problem. Presented the results of numerical experiments for various values of the parameters entering the equation in the two-dimensional case.

The paper discusses various options for constructing models of intellectual analysis of the state of poorly formalizable processes, described using fuzzy inference rules. A hybrid algorithm is proposed that combines fuzzy logic methods with a genetic algorithm that gives a fundamentally new quality.

In the present paper analytical solutions to suggested geometric models of equidistant curve formation for flat contours represented by second-order curves and areas bounded by them are considered. Geometric models are spatial and based on cyclographic representation. They differ from the known algebraic models and their solutions to the formation task under consideration in that they present capability to acquire a more complete and vivid spatial representation of interconnection and interrelation of all the geometric objects of the model on the stage of computer spatial visualization. Examples confirming the validity of the suggested geometric models of the considered formation task are provided. The models can be applied in automated cutting tool trajectory design for pocket machining on NC units.

In the present paper the analytic solution to the geometric model of formation of equidistant curves (contour-parallel curves) is considered for the case of flat boundary contour and an island within it. The geometric model is spatial and based cyclographic representation. It differs from the known models of the considered formation task and their respective solutions in that on the stages of computer visualization it allows us to achieve a more complete and vivid spatial representation of interconnection and interrelation of all the geometric objects of the model. An example proving the validity of the proposed geometric model of the considered formation problem is provided. The model can be applied in computer-aided machine tool trajectory design in pocket machining on NC units

This article is devoted to development of an automated service for media content delivery network when adaptive online streaming on the Internet. This allows automatically adjusting of the amount of transmitted data per unit of time (bitrate) with changing in quality of requested media content accordingly. Consequently, the quality will be underestimated to those using low-bandwidth data channels, and vice versa, the content will be provided with highest possible quality for those connected to high-bandwidth communication channels. In this process, a user does not take any part: client video player itself determines which bitrate will optimally display the content to a particular user in order to avoid video buffering with the highest possible quality ensured. Switching between bitrates can occur continuously with a decrease/increase according to changes in quality of currently available bandwidth. In addition to adaptive video broadcast, the developed service allows transcoding of video streams on the fly. After receiving of input RTSP/RTMP stream, the network converts it to RTMP/HLS multi-bitrate, resulting in the generation of video streams of different quality which can be supported by both mobile devices and personal computers.

Many modern models of informational defence represents by graphs and partial orders (posets). It is very important to resolve such algorithmic problems as searching of elements that satisfies some conditions (or, another words, to resolve recognition problems) in this models. Algebraic geometry is resolving such problems and find elements from algebraic structure that is solution of system of equations. But before searching the effective algorithms of resolving the systems, first better to answer the essential question: can we resolve the system efficiently? In this article we find the condition to poset which can be efficiently resolve every finite system of equations over the partial orders.

In this paper we consider not everywhere defined functions of multivalued logic. The problem of logical continuation of functions of multivalued logic in the class of disjunctive normal forms is investigated. We prove a theorem on the invariant extension of functions of multivalued logic in the class of disjunctive norms, which does not depend on the accepted coding. An algorithm is constructed for constructing a set of invariant points that are independent of the received encoding.

Problem of technical objects low contrast image areas analysis is actual. Even now the black and white photo materials are used along with colour images. Particularly it can be attributed to X-ray control. The majority of industrially produced photo layers are colourless. As a rule, images are analyzed visually. In particular such method is used in medical X-ray control. Up to a present moment there are no reliable algorithms capable of separating pathological and non-affected areas. If an image is sufficiently clear and contrast then it is analyzed using the primary photo-image. If the image has low contrast then a researcher, firstly, converts it into a pseudo-colour or three-dimensional and then analyses it. Such procedure is determined by complex dependence of many factors, but the most important are the following three: psycho-physiological complexity to distinguish the boundaries of the image, difficulty to create an algorithm capable of recognizing the norm-pathology boundary without help of a human, and inability of an average human eye to discern more than 10 - 12 gradations on black and white image. Existence of the mentioned factors led to various approaches to obtaining higher quality of images - the image pseudo-colour coding method, and the method of 3-D conversion. In the present paper the combination of the developed and patented by the author method for optical images analysis and well known method of computer image analysis using Femtoscan software (designed for electronic microscope images analysis) is considered.

Query optimization is an important part of any database application. The most effective method of an acceleration of search queries is use of index structures. It is known that queries which use the indexes (clustered and not clustered) are effective in the case of low percent of the repeating values in columns. If indexable data are not selective, use of the majority of types of indexes is not effective. Main objective of the performed work is extending of SQL Server MS for creation of indexes and increase in productivity of search queries. In the furtherance of this goal the high level language Net-application using C# is created. Embedded algorithm creates a bit scales for processing of relational tables columns with a large count of the duplicated values. In article it was conducted the review of the main existing methods of search query efficiency increasing and types of the index structures used in different database management systems. Examples of action of application for selection of values with use of bit indexes are shown. Testing of the created software product on tables with different cardinality allows to draw conclusions about the considerable abbreviation of time of data handling in case of using of bit indexes in comparison with other search algorithms.

The article focuses on the features of the dynamics of unilateral interactions of the elements of the brush-commutator unit of the traction electric motor of an electric locomotive within the scope of the problems of determining the conditions of motion without a gap interpreted as the quality factor of a current pick-up in dynamic loading processes. A mathematical model for the interaction of a brush, a collector surface and a pressing mechanism is proposed, which takes into account the possibility of contact failure depending on the parameters of the elements of the brush-commutator unit and the force factors including the effects of the vibrations of the traction motor body. The positivity of the complete reaction was used as the criterion for maintaining the contact. An analytical form of the conditions for the continuity of the contact between the elements of the brush-commutator unit is obtained on the basis of a comparison of the static and dynamic components of the complete reaction. The work shows the dependence of the analytical conditions of the continuity of the contact on the choice of the system parameters. It proposes a graphic-analytical method for determining the parameters ensuring continuity of the brush holder for the limiting stiffness of the pressing mechanism.

The work presents a methodical complex of studies of base metal and its coating composition, that allows to study the change in structural characteristics of material at micro-level, mezzo-level and macro-level. The effect of changes in structural state on the properties of coatings and base materials during treatment of cast iron parts working surfaces by air plasma spraying (APS) was established. Physico-Mechanical properties of coated samples and the features of their structure formation has been evaluated during experiments. An optimal composition of a powder mixture containing self-fluxing solid alloys and wear-resistant fillers, which provides enhanced performance in conditions of hydroabrasive wear is proposed. It is established that plasma spraying of the coating (65% PR-NH17SR4 + 35% KHNp-30) with subsequent heat treatment and reflowing leads to an increase in wear resistance up to 1.5-2 times.

The thermal plants operational efficiency improvement study relevance is associated with the temperature influence of heating the air required for the fuel burning and economic feasibility. The paper objective is to define the optimal value of the recuperator air heating temperature and to study the given temperature impact on the high-temperature unit operating efficiency. The recuperator air heating optimal temperature defining algorithm deriving appears to be the problem solving. The methods of the heat exchange equation mathematical modelling, optimization problem numerical solution, non-linear programming, and modern methods of the technical and economic assessment were used in the paper. The computational investigation results of the temperature influence of heating the air required for the radiant tube fuel burning on the thermal plant technical and economic efficiency are presented.

The article is devoted to the actual problem of information security of personal data, circulating on the internet portals of State government body and municipal government. Scientific development of technical aspects of the mechanism of electronic application of the public to the authority organs agrees with priority policy of creation of information society and electronic government, and personal data security is one of the tasks of integrated support of the state information security and this determines the relevance of the article topic. Basing on the analysis of legislation, content-analysis of portal centres of provision of state and municipal services, by carrying out experiments the problems have been found out and the proposals on technical information security of personal data while applying to the government body electronically have been developed.

As a result of the content-analysis of regional portals of Multifunctional centres of provision of state and municipal services, it has been revealed that in most regional portals of Multifunctional centres personal data are sent in open, unencrypted form, which threatens their security. To study the possibility of interception of people personal data two experiments have been fulfilled. As a consequence of the experiment all the sent people's personal data have been got. On the basis of the received information the model of threats has been developed for information systems of personal data of Multifunctional centre, for this system values of initial system security, probability of threats realization have been defined, assessment of the possibility of threat realization and danger has been done. The solution to the problem of probable data loss while filling in electronic application can be obligatory usage of data encryption protocol HTTPS on the internet portals of public authority, this protocol is intended to provide the three most important security aspects: encryption, authentication (of users), integrity. To get authentication of users Multifunctional centres will have to give people their own digital signature, with the help of which applicant's personal data will be certified; data should be signed with the help of the privacy key of a Multifunctional centre.

The results of the study are a software package aimed at secure data transfer, the layout of the site of a Multifunctional centre, recommended as a standard, proposals how to improve the legislation in the sphere of personal data security – will help to solve the problems of the society and state.

Gas cleaning systems are used in many industries and in everyday life. For example, trapping particles and droplets from process gases; air cleaning in spray booths; separation of particles in pneumatic transport systems; cleaning of air supplied to power plants. Typically, the main element of this system is a filter or a cyclone. Cyclones create great hydraulic resistance and cannot catch small particles. Filters, after a while they clog, they cannot be restored and they need to be changed. Therefore, the authors have developed a device capable of catching small particles with little hydraulic resistance. It has a simple construction. It lacks small parts and small channels. The device can be used instead of cyclones. Alternatively, it can be used to pre-purify gas flows in front of the filters. This will significantly increase the period of their replacement. The procedure of solid particles and droplets capture efficiency calculation in rectangular separators is presented. It is shown that high values of process efficiency are obtained in case of small particles separation. Recommendations on the selection of optimal technological and design parameters are suggested. If these separators are installed before the filters, they can significantly extend service life of filters.

The paper presents a generalized method for determining the service solid angle based on the assigned gripper axis orientation with a stationary grip center. Motion synthesis in this work is carried out in the vector of velocities. As an example, a solid angle of the android robot arm is determined, this angle being formed by the longitudinal axis of a gripper. The nature of the method is based on the study of sets of configuration positions, defining the end point positions of the unit radius sphere sweep, which specifies the service solid angle. From this the spherical curve specifying the shape of the desired solid angle was determined. The results of the research can be used in the development of control systems of autonomous android robots.

Results of pilot studies of influence of the average size of files, total amount of data and volume of the recovered data for the period of backup when using of the automated processes of creation of backup copies of figures for the medium-sized and small printing and publishing enterprises are provided. Experimental and analytical methods revealed the critical parameters influencing the speed of process of backup on condition of use of exclusively internal opportunities of the enterprises. As showed research, the most significant parameters are the optimum size of the file and total amount of data. The option of use of an archiving before direct copying of data is analyzed, positive and negative sides of this approach are shown. The optimum size of the file for process of backup at its use on one computer and without use of network technologies and external hard drives was established, its mean value makes 685 Mb. These researches allow increasing quality of backup process; will help with creation of the automated, autonomous and flexible systems of backup.

Currently, the effective technologies and modes development of electrotechnological installations is relevant. Power supply of electrotechnological and lighting load with calm character is usually realized from the busbars of a transformer. The effective operation mode of an electrotechnological and a lighting installation may be provide by the complex waveform current supply. In the article, the operation of the mixed load after switching in the network and the transient process are researched by the example of the low-voltage electrode water heater and energy-saving lamp physical models.

The purpose of the paper is study of the energy parameters and the transient process in a connection node included the electrode water heater and the energy-saving lamp with the complex waveform current supply and select the effective modes of the mixed load in the steady state after switching. It required the solution of scientific problems in the development of methods for study of mixed load with CWC in the transition from one stationary state to another, the transition process, to develop recommendations for the selection of effective modes necessary for the synthesis of the automatic control algorithm. The decision tasks have revealed that in the steady state after switching of mixed load works in the effective mode; the nature of the transition process with CWC changes.

A problem related to the actual problem of the process of water and salt transport in soil is solved in the paper; the review of scientific papers devoted to various aspects and mathematical support of the object under research is given. A mathematical model is proposed in the paper to carry out a complex study, taking into account: the colmatage of soil pores with finely dispersed particles with time; the changes in soil permeability coefficient, fluid loss and filtration coefficient; the changes in the initial porosity and settled mass porosity and an effective numerical algorithm based on the Samarsky-Fryazinov vector scheme with the second order approximation where the differential operators in equations are substituted by finite-difference ones. For the derivation of mathematical model of salt transport it is assumed in the paper that the pressure gradient in the canal is constant and equal to atmospheric pressure. The results of calculations on the proposed algorithms are presented in the form of graphs; a detailed analysis of these results is given. At the end of the paper, conclusions are drawn related to the analysis of numerical computer calculations. It is established that with scarce irrigation, the maximum absorption of water and the accumulated salt transport occurs in the upper layers of soil. Numerical calculations have established that changes in the rate of water transport in soil depend on: porosity, soil permeability, filtration coefficient, composition and structure of soil, and the porosity of settled mass. The process of salinity has reached equilibrium after the use in irrigation of salt water for several years.

The efficiency improving relevance of the energy grids based on internal combustion engines is presented. Consequently, the application possibility of the internal combustion engine high temperature cooling system in the power plant by using its positive effect was considered and analysed. The analysis of the experimental data, namely of the cylinder cover fire bottom temperatures and materials parameters measurement depending on the operating temperature is presented. The obtained experimental data of the cylinder cover fore bottom temperatures level made it possible to predict the forced ICE aggregate capacity increasing limitations.

The problem of sound insulation in the low-frequency region (up to 100 Hz) is relevant, but little has been studied theoretically and practically has not been investigated experimentally due to the lack of the necessary experimental base. Especially important is the solution of the problem for local isolation of low-frequency mechanisms by perspective mesh-plate flexible panels (MPP) for various configurations of isolated and protected volumes and at low first natural frequencies. The purpose of this study is to evaluate the effect of forced vibration panel and room volume ratio of the source of the perturbation and the protected volume. The objective is to develop a mathematical model, which can verify the adequacy of the experimental results obtained at frequencies above 30 Hz and acoustic reverberation chambers interferometer. As a result, a formula for calculating the sound insulation has been received, allowing taking into account the volume ratio of the shared spaces and the transition through resonance. The results of the research can be used in the design of direct soundproofing of low-speed mechanisms or for the organization of the first stage of soundproofing and modernization of the design of the MPP in relation to specific conditions and requirements for sound insulation.

State of the art technology implies the application of increasing power at high speeds, therefore various interference joints strength enhancing is an urgent task. On the basis of the review of the existing interference joints bearing capacity improving research methods, the approach being implemented by the joint internal member mounting surface modification with the help of grooves of shallow depth is proposed. The experimental results of the modification various parameters influence on the fit bearing capacity are presented. It is reasonable to use the given engineering solution for fit strength restoring when performing the repair work.

Kapovich, Myasnikov, Schupp and Shpilrain in 2003 developed generic approach to algorithmic problems, which considers an algorithmic problem on "most" of the inputs (i.e., on a generic set) instead of the entire domain and ignores it on the rest of inputs (a negligible set). Jockusch and Schupp in 2012 defined a generic analog of Turing reducibility. In this paper we investigate a generic reducibility of computably enumerable (c.e.) sets. We prove that there exists a pair of incomparable c.e. sets, that there is a complete c.e. set, that there are no minimal and maximal c.e. sets. Also we prove some analog of classical Sacks density theorem. Supported by Russian Science Foundation, grant 18-71-10028.

Based on the methodology of the regulatory, the main methods of mathematical modeling of the regulatory mechanisms of living systems at the molecular-genetic, cellular and organ-tissue levels are presented. The constructed mathematical models of the regulatory of the cardiovascular system, the liver and the thyroid gland are presented in the form of systems of functional-differential equations with delay arguments, and also results of qualitative analysis for these models are obtained. Computer models have been developed for quantitative analysis and assessment of the state of biological systems. The most common regularities in the functioning of systems and various behavioral regimes, such as stationary, self-oscillating, dynamic chaos and a "black hole" are revealed.

Beam structures are widely used as the main elements of structures in aircraft and rocket engineering, mechanical engineering and instrument making. During operation, beams can experience external influences of various types, which leads to contact of the beams. In connection with this, the construction of a mathematical model of the contact interaction of beams is an actual problem. The aim of the work are to construct mathematical models based on the kinematic hypotheses of the first (Euler-Bernoulli) and the third (Pelekh-Sheremetyev-Reddy) approximations, the creation of methods for calculating the highly nonlinear (geometric and constructive nonlinearities) mechanical structures under the action of transversal harmonic loads. The resulting system of nonlinear partial differential equations in a dimensionless form by the method of finite differences of the second order of accuracy reduces to the Cauchy problem, which is solved by the Runge-Kutta method of the fourth order. The convergence of the obtained solutions is investigated depending on the intervals of the partitioning over the spatial and temporal coordinates. A rigid limitation was imposed on the coincidence of the basic functions in chaotic vibrations for n and 2n partitions of the interval of integration over the spatial coordinate. As an example, we consider the nonlinear dynamics of two beams, the gap between which is equal to unity. It is shown that the transition of the beam structure vibrations from harmonic to chaotic occurs through a subharmonic cascade of bifurcations. Chaotic phase synchronization based on the Morlet wavelet is investigated. The values of the highest Lyapunov exponent were calculated by the methods of Wolff, Kantz, and Rosenstein.

In the paper it is proposed a differential method for measuring the maximum achievable transfer coefficient of active quadripole. A new structural scheme of a measuring device and a sequence of measurements and calculations that implement the method are proposed. The differential method is intended to measure transfer coefficient of the power by an active quadripole in the microwave range at the border of its potential stability. The parameters of the active quadripole have a dimension that corresponds to the dimension of the elements of the standard W-parameters of microwave electric circuits. The results of measurements of the maximum achievable transfer coefficient of microwave bipolar transistors are presented in the paper. The advantages of the method are: 1) a small error of measurement, that is less than 5%; 2) there is no need to make individual measurements in short circuit or idling mode; 3) the small dependence of the results on the coefficient of standing wave of the loaded measuring path.

The article considers results of experimental studies of a piston hybrid power machine with a slot seal of step-type. While experimental studies, the following parameters were taken as independent parameters: the type of cooling liquid (I-20A oil and MGE-46B oil were used), the injection pressure in the compressor section, the discharge pressure in the pump section, the crankshaft speed.

The experimental studies determined that using of low-viscosity oil I-20A made possible to reduce the temperature of the cylinder-piston group and the temperature of the intake gas.

We give necessary conditions for a tree semilattice to be weakly equationally Noetherian.

Evaluation of parameters of the expert structural model of normal hemodynamics in patients with arterial hypertension of the initial stage before and after special physiotherapy was carried out on the foundation of numerical methods of nonlinear optimization with conditions.A slight change in the consistency of the experimental data that were obtained after physiological treatment with the structural model of normal hemodynamics shows the lack of effectiveness of this physiotherapy for normalizing the regulation of blood pressure.

In this research, the annealing method in solvent vapor was adapted to produce single-crystal thin films of oligomers based on thiophene and benzene. Monocrystalline silicon substrates with a layer of silicon oxide deposited on it were used. Monocrystals grew from the solutions directly on substrates at a room temperature. Variable parameters for crystal growth were: solvent type (toluene, dichlorobenzene), solution concentration (from 1 g l⁻¹ to 0.03 g l⁻¹), method of application (spin-coating, drop-casting). The crystallinity and geometry of the synthesized single crystals were determined on a Carl Zeiss AXIO LAB.A1 microscope by microscopy and polarization microscopy.The substrates are already a complete part of the OTFT architecture (gate and dielectric layer). After plotting contacts of PEDOT:PSS organic field-effect transistors were obtained and they electrophysical characteristics were measured. It is established that in the obtained OTFT semiconductor crystals has hole conductivity with a hole mobility μ = 0.03 cm² V⁻¹ s⁻¹ in a linear mode.

Viscosity coefficient defining methods taking into account the turbulent component under the boiler various operating conditions at the subatmospheric pressureare considered in the paper. Currently, addressing this problem is of particular relevance for the vacuum boilers heat-exchange problems solution. The viscosity coefficient dependences in a wide range of the specific heat fluxes at the free convection and bubble boiling are obtained. The study results were obtained by means of the software complex ANSYS CFX and RPI model.

Planetary Rotor Hydraulic Machines (PRHM) with wave-shaped central gearwheels and floating satellites show notable engineering performance, at the same time, this subject lack in-depth study. A methodology of computing cross-sections of feed channels that supply power fluid has been devised to embrace a variety of modifications of planetary hydraulic machines. Design formulas have been proposed, and a comparative assessment has been performed related to the channel cross-section criterion. Locating channels in the sun gearwheel (having a lesser number of waves M) contributes to expanding channels. In the cases when channels are in the epicyclic gearwheel (N being the wave number), the following configurations M×N have been discovered as preferential: 6×8; 4×6; 2×4. A design concept to expand channel cross-sections by means of sequentially joining two PRHM stages of the same type has been studied. This concept is more efficient in the cases when configurations have the same number M=N and their sun gearwheel and epicycle are related as 2×2; 3×3.

Calcium silicates are considered as promising components of materials for hard tissue repair. The main attention is paid to the crystalline forms of these substances. In the present study, a series of amorphous calcium silicate hydrates with molar coefficient Ca/Si = 0.65 - 1.45 was prepared by precipitation in aqueous solutions. The samples were analysed using X-ray diffraction, FT-IR spectroscopy, SEM, TGA, BET. The dynamics of calcium silicate hydrates dissolution in Tris-buffer solution with pH = 7.40, corresponding to the acidity of human plasma, was compared with wollastonite and apatite. It is shown that calcium silicate hydrates actively dissolve in a slightly alkaline medium, ensuring the appearance of calcium ions in the solution in amounts that exceed the cation concentrations in systems with β-CaSiO₃ и Ca₁₀(PO₄)₆(OH)₂.

Theexperimental and numerical study of common used effective diameters for fluidized bed at a wide range of gas velocities was carried out. This work was motivated by Eulerian approach to modelling multiphase media. In the conditions of the experiments carried out and the Gidaspow drag model, the best agreement with the experiment was shown by the so-called modal effective diameter D_mod. For minor gas velocities, the diameter D₃₂ was corrected in order to best coincide with the experiment.

Optimization of the porous material geometry is caused by engineering needs in reducing the value of the pressure drop in the gas or liquid flow through a complex structure. Computer models of porous media in various configurations are constructed, the pressure drop is calculated depending on the flow rate for the created models. The geometry of the packing of randomly located intersecting spheres gives a nonlinear change in pressure, whereas the ordered packing of spheres and the structure of randomly arranged cylinders and spheres yield results close to the Darcy model. For a model of randomly spaced spheres with the same porosity of the medium as for other models, the resistance coefficient has a maximum value, which is due to a multitude of channels of complex geometry that create additional flow resistance. The experimental data of the pressure drop calculation agree well with the results of the numerical simulation, which indicates the validity of using such models for studying hydrodynamics in highly porous cellular materials. A detailed study of the material structure influence on the hydrodynamic calculation using computer simulation will allow creating samples of porous media with improved characteristics.

The paper considers the dynamics of the anti-vabration mount of a new design with the quasi-zero stiffness effect, in which the mounting element is an elastic rubber-cord casing of type I-09, and a load adding element (corrector) is a toroid-shape rubber-cord shell. A mathematical model is developed and motion graphs of vibro-isolated object in the range of 1-10 Hz are built.

The article considers the problem of choice the location of an industrial enterprise (production facilities, storage facilities and technical personnel). To solve this problem, the methods and means of determining the optimal location of the industrial enterprise, allowing for a comprehensive analysis based on various factors affecting the location of the enterprise. The task of determining the location for the production area of the enterprise is choice of the most optimal option, from the proposed on the basis of a number of methods. The methods of determination include: the method of weighing, the method of placement taking into account the total cost, the gravitational method, the method of cost calculation. Analytical studies and results after solving problems using each method. In General, the article solves the problem of choosing the location of industrial areas of the enterprise on the basis of different requirements for the created enterprise or its structural unit located in the region.

The article describes the calculation technique for pressure regulators of a new type, in which a circular ring made of elastic material is used as the locking-regulating element. The design of the regulator is protected by a patent and is characterized by simplicity, high reliability, economy and good performance. It is necessary to find optimal design solutions, to conduct theoretical and experimental studies of prototype regulators. The above theoretical calculation allows us to determine the design dimensions of the regulator elements for the given operating conditions and to obtain the necessary design solutions at the engineering level.

The analytical connection of the number of impacts with the energy of gravity forces of the falling weight and instrument has been determined. The energy realized when striking the rod has two components: energy of the free falling weight when moving relative to the casing which occurs before the moment of the impact with the collar, and energy of the gravity forces of the weight and casing, which arises additionally while vertical lowering to the rod penetration depth in the transition process. The soil strength is numerically determined as per the normal stress value at the end of the rod being penetrated into the soil. The numerical determination of the normal stresses has been performed by means of the theorem on the mechanical system motion quantity change and theorem on the kinetic energy change. The identity of the numerical figures of the normal stress value at the end of the rod and specific energy of the impact penetration of the cylindrical rod into the test soil has been determined. The analytical connection of the impact energy and soil strength parameters with the dynamic instrument parameters has been obtained – with the falling weight mass, instrument casing mass, weight falling height, rod penetration depth, instrument geometric parameter. For the first time in relation to the impact instrument the loss of the kinetic energy and efficiency of the falling weight impact process in case of the direct inelastic impact of two bodies has been determined according to Carnot theorem. The values of the soil deformation specific energy and of normal stresses under the flat end of the rod for soil classes in the function of the number of the dynamic instrument impacts have been determined.

The paper deals with the main types of foulings on the boilers heating surfaces. The mathematical modelling of the fire-tube boiler processes including the fouling formation was carried out. The fire tube design making it possible to reduce the fouling formation velocity is proposed.

Plastics of various types, such as ABS, PLA, etc. are used to create prototypes of parts by the method of layer-by-layer deposition (FDM). The low cost of these plastics determines the relevance of using this type of prototyping when developing models. One of the main problems with the use of 3D printing is plastic shrinkage when using heating platforms. The article presents the results of the study of the "Cube" detail after different printing modes to determine the most preferable mode when using universal ABS plastic. For the production of products with high requirements to the geometric characteristics, recommendations on making changes in dimensions at the stage of modeling parts are proposed, which allows us to eliminate the problem of material shrinkage.

Coordinate measuring machines (CMM) are gaining popularity in manufacturing enterprises among the most universal means of determining the geometric characteristics of parts. Among a large number of CMM manufacturers' offerings, a suitable model can be purchased based on the dimensions of the monitored product, the accuracy of the measurement and a number of additional functions. Some manufacturers claim that the location of the part in the measuring zone and the location of the calibration of the measuring tip do not affect the measurement result. In this paper, experimental studies of the measurement of the reference ring on hexopod (six-axis) CMM in different positions, different distances from the calibration site along the sphere, and different positions of the calibration of the measuring tip are presented. From the results obtained, one can see the most approximate values of the obtained values of the diameter of the ring and the deviation from roundness, depending on the position of the calibration sphere and the calibration angle of the measuring tip. The work shows the difference in the results of multiple measurements of the reference ring, depending on the measurement technique.

A boundary value problem for a second-order semilinear singularly perturbed ordinary differential equation with two small parameters affecting the convection and diffusion terms is considered. We use Newton and Picard iterations for a linearization. To solve the problem at each iteration we apply the second order difference scheme on the Shishkin mesh which converges uniformly with respect to both singular perturbation parameters. To decrease the required number of arithmetical operations for resolving the difference scheme, a cascadic two-grid method is proposed. To increase the accuracy of difference scheme, we investigate the possibility to apply Richardson extrapolation using known solutions of the difference scheme on both meshes. The results of some numerical experiments are discussed.

New technologies provide much more progressive ways of working with information. Access to information is provided from anywhere, without geo-referencing. All this causes the emergence of new threats and vulnerabilities. An important task is to ensure the security of data, identify compliance of protection systems with the regulatory framework and current threats to information security. Timely audit allows to confirm the necessary level of security or to notify about its shortcomings. The paper presents a developed model for assessing the security of information using intellectual means. The software algorithm for auditing the security status of an automated system for an information security specialist has been implemented and tested. The article presents implemented software for auditing the system of protection of automated systems. The preliminary data of approbation of the developed algorithm and program complex are demonstrated.

The information about a part geometric shape and configuration precision is one of the life-cycle backgrounds. Actual knowledge about cylinder surface shape is principal for viscous incompressible fluid transfer (ink), in a printing system, in particular. High quality assurance management for parts engineering is one of the primary tasks, which can be solved by control automation as well as the by united concept formulation for parts precision; the offered implementation tool is the algorithm design of a geometric model part shape. The developed algorithm novelty is taking into account the element information value, coordinate planes and axis, materialized by parts data base sets. The practical realization of the algorithm is presented in this paper. The digital visualization of the transfer parameters calculation results addressed for a viscous incompressible fluid between rotating cylinder surfaces depending on contact zone varying is presented.

Correct techniques of and approaches to the analysis of production stability and measuring systems and management of products quality are significant for the tasks of development and improvement of a mechanical engineering enterprise quality control system. More opportunities arise for production quality managers enabling their dealing with claims and defects, elaboration of corrective actions and application of statistical methods for the analysis of quality of products. In this article, a technique for the analysis of defects of mechanical engineering products based on the system approach is suggested, and an example of its practical application is described. The main distinctive feature of the suggested technique consists in a description of each part or component of an assembly or a unit in the form of formulas offered at one of the stages. Application of the technique for the analysis of defects allows systematizing data on potential defects, probable causes and possible consequences of them, thus that leading to improvement of the management process and quality of products of mechanical engineering.

The investigations of the process of heat and mass transfer in the evaporation of model liquids (distilled water, alcohol mixture, kerosene TC-1) in a vacuum chamber (VC) under parametric ultrasonic influence (UI) and vacuum influence (VI) on a liquid with the purpose of using the obtained results for the development of a methods for designing the evaporation system of unused liquid residues of rocket fuel remaining in the launch vehicle (LV) tanks at the end of the mission. The initial data, variable parameters, assumptions and limitations have been determined. Experimental dependences of the temperature variation of model liquids and gas in a VC under UI under conditions of reduced pressure (up to 0.065 kPa) are obtained. The masses of evaporated model fluids and the rate of evaporation are determined. A comparative analysis of the experimental data obtained for various model liquids was carried out, which showed that the evaporation rate increases with increasing amplitude of the bath bottom vibrations, with the highest evaporation rate under the same conditions for kerosene TC-1.

The mathematical model (MM) is developed for the description of evaporation process of model liquid with a surface of the cylindrical capacity (CC) for application of power expenses optimization at convective and conductive influence. Also processes of the changes of liquid and steam-gas mixture (SGM) temperature were considered in the MM. The optimization of power expenses was based on the Pontryagin maximum principle with application to process of liquid evaporation. For the modeling of heat and mass transfer processes with evaporation in cylindrical capacity at the combined influence, the system of the ordinary differential equations was used. At some admission, the MM allows to perform optimization of the cyclogram of a convective expulsion (and heating systems operation and to define a tendency of power expenses reduction at consecutive inclusions and switching off the SGM expulsion and heating of walls of cylindrical capacity with a liquid film on its walls. Power expenses of conductive heating of liquid and a expulsion of SGM from cylindrical capacity are accepted for an optimality criterion. Time intervals of heating the walls with liquid and expulsions of SGM providing minimization of power expenses for evaporation of the set mass of liquid are defined with the help of numerical modeling. The result of calculations without optimization show the increased power expenses are carried out.

The dynamic similitude criteria for detachable sections of rocket like fairing leaf are presented. The criteria ensure the similarity of the center of mass and attitude motion of the small-scale model to the full scale body. The application of the presented criteria is illustrated by a numerical experiment. These criteria can be used to conduct small-scale experiment for the investigation of the re-entry motion of launch vehicles and its parts.

The aim of the article is to study the design of rubber-cord compensator for damping and compensating pipes movement and vibration isolation of other structures in vibroactive systems with the required specifications. As a result of calculations, graphical "force-deformation" curves were obtained in the axial and radial directions, the stiffness of the compensator was determined on their base. The stress-strain state of the rubber-metal element is determined, so one concludes that the compensator under study meets the strength criteria.

A theoretical study of the influence of various technological factors on the force parameters of the hardening process of a cylindrical blank by a method of surface plastic deformation was performed. Based on the approximate model of plastic deformation propagation, an engineering technique has been developed that allows one to specify the force regimes of the surface hardening process with a toroidal roller, taking into account the required degree of deformation of the hardened layer, taking into account the mutual influence of the geometric parameters of the workpiece, the deforming roller and the required depth of cold work. The results of the theoretical study are in good agreement with the known experimental data and can be used in the development of technological operations for hardening machine parts by rolling in rollers or balls.

The modified Viterbi algorithm for imputation of incomplete sequences using hidden Markov models is presented. It is applied to the problem of imputation of incomplete motion data. It is shown that modified Viterbi algorithm outperforms imputation of gaps with the mean of neighbor observations.

The influence of machine setting parameters on the behavior of the cylindrical roller during the processing of its ends is investigated. The regularities of motion and accuracy of double-sided processing of rollers have been established. A system of indicators is proposed that relates the characteristics of rotation to the accuracy of processing. The optimum shape of the roller rotation frequency curve is established, which ensures the highest processing accuracy for these grinding conditions. Practical recommendations for the choice of technological parameters are given.

In this paper, we introduce an analog of the edit distance (also known as Levenshtein distance) for free left-regular bands. We find formulas for calculating the number of pairs of words, having a specified edit distance, and for calculating the average value of the edit distance for a free left-regular band of the rank n.

The article discusses various algorithms for character recognition, describes their advantages and disadvantages. The modified algorithm of character recognition based on the template method is proposed, its block diagram is given, the results of testing are presented, as well as the possibility of its application in the system of automated test forms verification. The article presents experimental data on the probability of correct recognition of a symbol of an arbitrary number, depending on the number of loaded characters in the pattern obtained using this algorithm.. The algorithm developed by the authors is planned to be used in the development of a testing forms verification system, both for entrance tests and for various disciplines studied at the University. This system will allow to automate the test results verification, create a test results database and on its basis to create various reports types.

Both the comparative testing and SEM-control of crack surfaces for steel, polymer and 3D-printed polymer gears were carried out. Computer mechanical fatigue failure modelling correctness for steel wheels and in a less degree for polymer ones due to polymer inhomogeneous inner structure was shown. The SEM-characterization indicated that used type of fatigue failure modeling for 3D-printed polymer gears needs corrections due to the specific uneven gears surface shape, inner cavities presence and polymer deformation features as a result of both insufficient filament melting process, and microstructural polymer features. Surface fluorination aimed to 3D-printed gears friction ratio decreasing was tested. Gears modification was resulted to surface layer forming leading to wear halving to 0,3.

At the present, the actual task is using 3D printers for the manufacture of certain objects with a given level of price / quality ratio. In many cases, it is economically feasible to use a low cost 3D printer. Therefore, it is necessary to have models that predict and classify the printing quality of such printers. The work has involved the development and assembly of a low cost 3D printer. For this purpose, the creation of geometric models of the component parts and the printer itself was carried out, and engineering calculations and optimization of the received designs were performed. It has been developed a printer control system. An experiment was conducted to produce cubes with different printing parameters on such printer. Based on regression analysis, linear and logistic regressions were constructed. Linear regression will allow to assess the quality level of the result depending on the printing parameters, and the logistic regression will allow to classify and predict the probability of manufacturing objects with a given quality level. The influence of each of the print parameters on the quality and result of the classification was analyzed.

The problem of deep drilling in difficult-to-cut materials, especially when manufacturing aircraft and rocket and space technology products, is exists. In this study, the features of increasing the efficiency of drilling by sharpening of the chisel edge are discussed. The cut chip thickness value is calculated; determined the geometric parameters when drilling by twist drills with various sharpening of the chisel edge. It is found, that the positive rake angle along the chisel edge, which was shaped by circular sharpening, provides stability of the cutting process and self-centering of the twist drill in the hole.

An approach to the development of a control subsystem for the technological process of smelting copper-Nickel raw materials, which allows to stabilize the loading of charge materials into the furnace, is proposed. The structure of the control subsystem is described. The control problem, the control quality criterion, the control object model, control and perturbing effects are considered. Single-circuit and combined variants of subsystems of quality management of products of melting are offered. It is established that the control subsystem stabilizing loading of charge materials in the Vanyukov furnace should be combined: in addition to the feedback loop, it should contain a perturbation compensator on one channel, but as calculations show, the quality improves if all perturbations are compensated.

The paper presents the results of thermal experimental studies, the purpose of which is to obtain the values of the gas flow temperature by the method gradient of the volume (mass) consumption. Explored the pipeline that is heated for on the short middle section. An equation was derived to determine the temperature of the gas in the heating zone by the measured static pressure before heating and after it and the gas consumption before and after heating. The practical significance lies in determining the thermodynamic parameters of the gas in the in the tract of the electrothermal Microdrive of a small spacecraft, when the experimental conditions and design features of the engine do not allow other methods to be used.

The mathematical model of the contact interaction of a multilayer nanostructure consisting of two nanoplates and nanobeams between them with small gaps was constructed for the first time. A modified moment theory is used to describe the size-dependent effects of a real nanostructure. The upper and lower layers are nanoplates, obeying Kirchhoff's kinematic hypothesis, and the middle layer is the Euler-Bernoulli nanobeam. Contact interaction is accounted for by the model B.Ya. Cantor. Nanoplates and nanobeam are isotropic, elastic, and they are connected through boundary conditions. The effect of the gap between the layers and the noise field is studied. To solve and analyze these constructively nonlinear problems, the methods of the qualitative theory of differential equations, wavelet analysis, and methods for analyzing the sign of the largest Lyapunov exponent are used. The differential equations system reduces to the Cauchy problem the Bubnov-Galerkin method in higher approximations and finite difference methods with approximation O(h²) and O(h⁴) with respect to the spatial coordinate. Next, the Cauchy problem is solved by the Runge-Kutta methods of the 4th, 6th, 8th accuracy order in time. The analysis showed that the gap size essentially depends on the interaction of the elements of the multilayer nanosystem and on the nature of their complex oscillations. Also, the presence of a noise field involves the contact interaction of elements that were at rest with the previous values of the remaining parameters.

Fast and convenient search of information on a large number of servers simultaneously to a large number of users at enterprises allows for the use of search engines. Since such a system is complex and consists of a large number of applications, it is effective to use the theory of multi-agent systems to create it. For a more systematic search, we suggest using the methods of ranking the results obtained. The article describes the developed mathematical model for determining the page indicator based on ranking factors for determining the position of the page in search results. In the proposed architecture, the simulation results are processed.

The results of calculated theoretical and experimental studies aimed at justifying the use of calibrators, allowing to take into account the uncertainties associated with the difficulty of taking into account the radiation coefficients of controlled surfaces in non-contact pyrometric temperature measurements are given in the work. The relevance of the research is related to the requirements for ensuring the accuracy of non-contact temperature measurements at the level of instrumental errors of pyrometers declared by their manufacturers. Currently, pyrometric measurements are used in virtually all industries and this causes the relevance of the presented research results and proposed technical solutions. The functional scheme of the calibrator using replaceable surface samples is proposed, the temperature of which is measured by pyrometers.

Safety friction couplings have been applied in mining, industry, construction, agriculture, transportation, and public utilities. They are used in free shafts uncoupling in critical situations when the value of torque exceeds the permissible value under short-term overloads. Compared to other safety couplings such as destructive element couplings (with shear pins), gear clutches (cam, ball), friction couplings transmit much larger torques being relatively small in dimensions. They have a small locking force, and better smooth running characteristics. The advantage of using multidisk couplings is the possibility of increasing the value for the limit torque by increasing the number of disks (due to the increased area of adjacent surfaces). Operation of safety friction multidisk couplings is influenced by various factors, an understudied relationship between the response speed of a friction coupling and the rate of the applied load rise being among them. The paper presents experimental data on a safety friction multidisk coupling operation on the test stand, and that allows one to fill out this gap.

We consider the supply management problem in which a product is supplied by batches. For all providers, the volumes of these batches are known. The total preference of the supply assignments is maximized and the number of providers for the consumer with a maximum volume of demand is minimized. For other consumers, the upper bounds on a number of providers depend on their demand. The NP-hardness of finding a feasible solution to this problem is shown. A bicriteria model of integer linear programming (ILP) is constructed for the problem under consideration. We showed that the cardinality of a complete set of alternatives (CSA) is polynomial. To search for solutions of CSA, we construct and investigate experimentally the single-criterion model of ILP. A heuristic algorithm for finding solutions close to the Pareto optimal is proposed. It is based on fixing values of a part of integer variables and solving the smaller-dimension ILP problem. This algorithm is implemented using the CPLEX solver. The results of the computational experiment for the heuristic algorithm on random instances are presented.

The currently used methods for controlling the operating modes of a centrifugal pump due to interchangeable rotors and throttling do not always allow us to obtain the required operating parameters of the pumping station. The purpose of the study is to obtain the technical characteristics of the use of a variable frequency drive. The use of frequency regulation on centrifugal units for the transportation of oil is currently one of the main most economical methods. The task of continuous monitoring of operating modes in the case of frequency regulation of the pump unit of the main oil pipeline and the development of optimal methods for controlling the operating modes is posed. The authors have developed a system of continuous control of operating modes for frequency regulation of a pump unit (SCCPU) - a software complex consisting of two stages of data collection and processing and simulation of process operations with issuing recommendations on optimal methods for controlling modes for frequency regulation of the pump unit operation on the main oil pipeline. The use of the SCCPU system will improve the efficiency and reliability of the entire facility, it is easy to integrate with any ACS software, since DDE and ODBC technologies are used in programming.

Laboratory benchmarks for mechanical testing under conditions of static and cyclic loading are considered. The analysis of the stress-strain state (SSS) of prismatic benchmarks having stress concentrators in the form of U-shaped grooves is presented. The use of benchmarks of this type makes it possible to model the main features of SSS of various designs: the stress level and the type of SSS, characterized by the ratio of the principal stresses in the zone of the maximum stress level arising in the design. As a characteristic of the SSS type, the article uses the coefficient P, the ratio of the first invariant of the stress tensor to the second, introduced by the researcher Smirnov-Alyaev, and also the coefficient K_σ – the coefficient of concentration of equivalent stresses that arise in the sample under load. The main regularities of the change in the type of SSS of the material in the working zone of the prismatic benchmark with the change in the values of its design parameters are revealed. These regularities make it possible to carry out a justified choice of the geometric parameters of the benchmarks of this type for the experimental study of the resistance to fatigue failure of various materials and structural components of various shapes made of them.

The article emphasizes the importance of taking into account the rigidity of the stress-strain state (SSS) when evaluating the static strength of parts and elements of highly loaded structures. The description of the universal characteristic of the SSS allowing to estimate the SSS rigidity in the construction zone is given. The estimation of the SSS rigidity in the zone of destruction of the experimental model of a choke unit with a spherical body under its quasi-static loading by internal pressure is considered. A calculation and experimental technique for estimating the limiting state of spring-steel 50CrV4 steel under conditions of biaxial stretching based on the use of laboratory prismatic samples for evaluating the strength of a material under a biaxial stress state is described. The results of numerical finite element analysis of elastoplastic deformation of prismatic samples performed in the MSC Marc software package are presented. The obtained results show a significant influence of the SSS rigidity on the ultimate characteristics of the material of the steel used in comparison with its traditional strength limit.

Automation as a branch of engineering science forms and studies methods of control of objects, the main essence of which is to form the structure of the regulator and calculate its coefficients. The number of regulator structures is limited, the most common of them is a serial PID, i.e. a regulator having a proportional, integral and derivative channels connected in parallel, and the regulator itself is switched in series with the object. Thus, most of the publications on automation are connected with the calculation of numerical values of the regulator's coefficient and analysis of the results of its use. Along with the publication of the results of such a calculation for increasingly complex objects, there are still rather big stream of papers, that solve the problem of calculating the regulator for objects, the control of which is no longer of great complexity due to the level of the achieved technology. Therefore, the question of dividing the classes of tasks into those that have already been solved, and those whose solution has yet to be found is relevant. It is required to establish a minimum level of complexity of such problems, and it is also useful to compile a list of obsolete methods, the use of which without cardinal modification is fruitless in comparison with the potential of other methods, which became possible due to the latest achievements of theory and rapid development of computing facilities. Some scientific schools traditionally use obsolete approaches. One of the reasons for this may be their lack of awareness of the latest achievements; another reason may be inept use of these methods, which generates errors and disappointments in them. This paper reveals similar errors and suggests methods of correct calculation. When used correctly, the numerical optimization is the most effective tool for the said problems.

Controlling an object with delay remains an actual task, since each object has a delay. If it is not introduced into the model, it means not its absence, but only that the delay is not the main factor that forms the transition process. However, if it is not taken into account, this can lead to a discrepancy between the results obtained in theory or in simulation with practical results. In work [1] it was suggested to use the same model of objects to compare the design methods of regulators, which will allow ensuring the objectivity of comparing different design methods. In particular, in [2] the same problem is solved in three ways, and by the result conclusions are drawn about the advantages of some methods over others. Unfortunately, in this article [2], not all methods are applied. In particular, the method of numerical optimization is not investigated [3–5]. This paper fills this gap.

At present, current methods and means of enterprise risk management are not integrated within the framework of a single methodology. Accordingly, they can be used only when solving particular problems. In connection to this, one of the most prosperous risk management concepts is controlling. It provides wide opportunities for integrated consolidation and development of various management schools scientific views. At the same time, attention is focused on the instrumental and information support of management processes.

The target of current research is to improve the process of information risk management on the basis of an organizational approach. Objectives of the research: to study the possibilities of existing organizational management methods application to protect information in corporate systems, to develop the concept of an organizational approach to the formation of an information risk management system. The object of research are the risks that arise during the information processing. The subject of the study are models, algorithms for managing information risks.

The result of the research is the risk-controlling of information security method, which made it possible to improve the efficiency of information risks management at the ship repair enterprise due to the synergy together with the improvement of various business processes. The method was tested, positive economic effect received up to 16% of the annual budget. The obtained results can be used as a fundamental basis for research the methodology of information risk-controlling development. It is possible to apply the assessment results obtained by the method implementation in simulation models, statistical calculations, the ISO 27001 PDCA cycle, and quality management.