The work analyzes the process of bending the sheet work piece to obtain shaping of sheet metal parts and profiles. The analysis is carried out on the basis of strength calculations of elastoplastic bending of the metal plate. When pressing such a plate, in practice, a spring effect is observed when the curved blank changes its shape under the influence of residual elastic deformations at the end of the pressing process. To compensate for the spring effect, it is necessary to determine the values of elastic and plastic deformations in the sheet blank. The work considers the method of calculation of these values on the basis of available experimental works. Conclusions have been drawn and practical recommendations can be used in the process of setting process parameters for pressing sheet blanks.

We consider interval geometric modeling of complex multi parametric systems having a set of parameters of different character. Some of the parameters may have interval indefiniteness. System information basis is incomplete one. The processed information depends on continuous, discrete and conventional data. Geometric model has a form of matrix and each element of it corresponds to some state of the system. Each state is described by interval function of continuous input and output parameters. The set of interval functions generates some discrete set of multidimensional surfaces in discrete space. We use this approach and our modeling algorithm to find predictive model of drape coefficient. The algorithm is based on linear approximation of numerical factors in factor spaces. Interval functions make it possible for us to vary some numerical factors within the given intervals. As an example, the interval model of fabric drape coefficient is found. Fabric thickness and closeness of texture are considered as input parameters.

The paper describes the process of designing the cutting tool feed drive of a special metalworking machine, which due to the circuit solution and automatic control system will increase the productivity of processing one cell of wafer background on sheet material up to 10–15 seconds. On the basis of the analysis of the technology of milling of a given regular pattern of wafer background and peculiarities of the equipment operation it proposed to replace the traditional ball bearing gear in the cutting tool feed drive with a flat combined crank-slide mechanism. Geometrical parameters of the lever transmission mechanism calculated in accordance with the known dimensions of the regular cell pattern and the recommended value of the angle of motion transmission. The analysis of kinematic and power characteristics of the lever mechanism allowed to justify the technical characteristics of the electric motor. In order to realize the required trapezoidal law of the output link speed change, the inverse problem of kinematics solved, numerical values of the instantaneous angular velocity of the input crank and pulse control signals to the servomotor obtained.

The paper analyzes the issue of calculating the endurance of the body of lowflying orbital objects from cyclic temperature alternating deformation beyond the limits of Hooke's law. The practical absence of direct calculation methods is stated. An indirect calculation is proposed on the basis of available experimental data on mechanical tests of samples with the «stress» parameter and an algorithm for transition from actual deformations to equivalent stresses. The calculation method is based on the use of the existing experimental fatigue curve under a symmetrical bending cycle, the results of static tensile tests at extreme cycle temperatures, and a generalization of known information about the patterns of changes in the endurance parameters of the material under consideration in relation to the conditions of cyclic temperature alternating deformation. The adequacy of the methodology is verified using the example of depressurization of the housing of the Zarya orbital module of the international space station, made of AMg6 alloy after ≈120,000 cycles of alternating temperature loading. The difference between the calculated and actual endurance of the AMg6 alloy is within the natural range of 20 % during fatigue testing.

The article presents the results of the development of indicators for monitoring the process of developing standardization documents. An integral part of the management of the standardization document development process is the monitoring system. The monitoring system allows you to monitor and control key indicators of the standardization document development process. Also, the use of a monitoring system makes it possible to form a reference base for analyzing the causes of deviations in the values of indicators. At the same time, an important task is to evaluate the effectiveness of the monitoring system and the mathematical justification of the indicator for evaluating the effectiveness of the monitoring system, taking into account errors in the implementation of the monitoring process.

Nowadays the organization of domestic serial production of high-tech products requires a lot of time. On the one hand, the reason is the restructuring of logistics chains with foreign suppliers, on the other hand, the building of cooperation in the country. For example, the duration of the implementation of promising production projects in the space industry is still years. Factories are changing approaches in the organization of work – one of the main ways to influence the duration of production is to reduce the time of their own production cycle. As a rule, the analysis of the organization of serial production begins with the final assembly, which determines the tact of work for all other sites that produce components.
When evaluating the effectiveness of the organization of assembly production, criteria and factors are determined. The time of the product assembly cycle is taken as the efficiency criterion. It is necessary to determine the degree of significance for each factor and understand their mutual influence on each other.
The purpose of the research is to develop a unified system of factors affecting the cycle, and a method based on this system for evaluating the effectiveness of the organization of assembly production. The article considers the technological process as a factor affecting the product assembly cycle.

The pivot jewel bearing is an important node of some classes of industrial equipment; at nominal operating modes, the speed of relative rotation of the contact surfaces can reach 103 revolutions per second, while the operating time can be measured in years; under such conditions, it is necessary to take into account the wear of the contact surfaces; in this paper, a technique for modeling the dry friction wear of a fast-rotating support pair is proposed, taking into account changes in the properties of materials due to surface heating, based on solving the wear contact problem in a stationary formulation using Archard’s law; the effect of taking into account the temperature dependence of material properties in wear modeling process is demonstrated.

Paper is devoted to development and research of the fifth generation greenhouse climate automatic control system. This system is based on fuzzy logic toolbox and it allows to automate control processes using the latest developments in this field. In the work the concept of «microclimate of greenhouse complex» for the region of the risky agricultural zone when growing large strawberries in a closed ground.

The paper studies the optimization features of low-voltage electrical network modes for energy-efficient power transmission. The main features of these networks are the high values of the zero-sequence voltage unbalance factor and the mismatch of voltage values with the necessary requirements. Therefore, balancing the loads by phases and reactive power compensation are chosen as measures to improve the listed network parameters. One of the main factors for the effective solution of this problem is the determination of load balancing points and reactive power compensation, as well as the required power of the devices used. To solve the multicriteria problem of determining device connection points, an analysis of existing objective functions is carried out. As a result, a target function is proposed that includes costs, voltage losses, zero-sequence voltage asymmetry coefficient. When solving the optimization problem with the help of the proposed objective function, the voltage values and the voltage asymmetry factor at the consumer connection points will be within the required limits. The results of a study of the optimization function using the example of a model network are presented. The calculations are carried out in two stages: the search for sensor's nodes, then their study for optimality. All calculations are carried out in the MATLAB environment, taking into account voltage losses and power.

With the help of the methodological base of the study (the foundations of probability theory and mathematical statistics), the processing of the experiment conducted at the research object is carried out. This object is the mechanical workshop of CJSC Sibgazstroydetal, which is engaged in providing for the needs of the gas, oil and energy industries. In this paper, the issue of determining the conductive low-frequency electromagnetic interference (EMI) by the coefficient of the n-th harmonic component of the voltage (KU(n)) is studied in detail. Harmonic distortion is a constant phenomenon in electrical networks. Higher harmonics have a negative impact on the electrical network, including on electric consumers (reduced service life, productivity, etc.). The problem of non-sinusoidal voltages has been studied for quite a long time and the results obtained during these studies confirm the presence of a large number of damages to electricity consumers who are in operation. The probability of occurrence of conductive low-frequency EMF by KU(n) at the research site is determined. The paper analyzes the results obtained with the help of the conducted research. According to the results of the analysis, the relevant conclusions are presented.

The paper raises a variant of architecture of realization of logical line protection on the basis of implementation of modern technologies. The idea of development and implementation of digital substations, the core of which is the application of IEC 61850 standard, has been developing at a great pace in the world. The appearance of this standard in substations opens new ways of realization of protection of electrical installations. In this article we consider the method of construction of line protection using the method of logical selectivity, and as the main terminals are considered Sepam devices series 1000+, as one of the most widely distributed devices in the electric power industry of the Russian Federation, the basic support for the standard IEC 61850.

A new method for measuring electric field strength is proposed. The method is based on the mean value measurement method, which uses a dual electroinduction spherical sensor. The use of the dual sensor for the method implementation allows to extend the functionality of the method by mean value. The method of measurement by the mean value assumes simultaneous measurement of two values of intensity E1 and E2 in one point of electric field with opposite sign errors. As the theory of construction of the new method has shown, it is possible to determine not only the measurement result as an average of two values of the strengths, but also to estimate the error of the measurement result and tentatively determine the distance to the field source. In order to determine the distance to the field source, a coefficient of the ratio of the two found strengths at each point of the field is introduced, by which the empirical dependence of the relative distance to the field source is found. The relative distance is the ratio between the radius of the spherical sensor and the distance to the field source. By determining the relative distance at each measuring point according to this relationship and substituting it into the known expression for the error, the error of the result at the measuring point is determined. The relative distance is also used to determine the distance to the field source. Thus, the new method of measurement allows to increase the accuracy of measurement of electric field strength, determined by the relative distance to the source of the field.

Research results into the automating the processing of measurement data obtained from the Brillouin optical reflectometer, light guides containing various types of optical fibers are presented in this paper. By analyzing the parameters of the Mandelstam — Brillouin scatter obtained from Brillouin reflectograms, we can classify optical fibers in the studied telecommunication optical cables. This makes it possible to evaluate the change of the Brillouin frequency shift and determine the longitudinal fiber tension. The initial values of the Brillouin frequency shift and the profile of the Mandelstam — Brillouin scatter spectrum are different for each fiber type. The programs for automated processing of Brillouin reflectogram data are discussed. Estimation of the level of the back-reflected signal allows you to identify the factor, that had a predominant effect on the parameters of the Mandelstam — Brillouin scatter signal in the studied sections of optical fibers, and to compensate for the influence of temperature changes in the longitudinal strain distribution graphs. After that, we can plot a graph of the distribution of longitudinal strain along the fiber, caused precisely by mechanical influences on optical fibers. Conclusions about the accuracy of the estimates obtained by various algorithms, based on the accumulated experience in working with the presented programs are drawn.

The unified reference system for the geometric characteristics of the part is the Cartesian rectangular coordinate system, which is materialized by sets of design datums that limit the part to six degrees of freedom: three linear and three angular. ISO standards for geometric tolerances do not use coordinate systems. In this context, research in the field of increasing the accuracy of parts by introducing linear and angular coordinates of part elements is relevant.
The paper presents the second part of the article Unified Reference System for Geometric Characteristics of Dimensional Elements of Parts, which focuses on the geometric characteristics of cylindrical elements of parts. It is shown that the datums of cylindrical elements are the axes of cylinders of maximum material capable of restricting four, two and one degrees of freedom for the part depending on the functional purpose of the element. The accuracy of coordinating dimensions should be specified by symmetrical tolerances for linear and angular coordinates of elements.

The results of determining the stability and variability of the main characteristic of glass capillary reference viscometers — conversion coefficient — by analyzing a set of data on viscometers having different diameters of the measuring capillary are presented. It is shown that the mean values of the sample differ from the mean values of the symmetric normal distribution curves within (2–4) %, as well as the correspondence of statistics to the normal distribution law by means of the inverse standard function and histograms showing the degree of correspondence of the sample distribution to the theoretical one.

With the advent of new technologies, the requirements for the sources of reference vibrations are becoming more stringent. They must be compact, quickly reach frequency, operate in a wide temperature range and have a small relative frequency drift in the operating temperature range.
Changes in ambient temperature are the most destabilizing factor for the oscillator output frequency. Ensuring frequency stability over a wide temperature range is a pressing task.
Thermal compensation allows increasing frequency stability over a wide range of operating temperatures. This is achieved by compensating for the effect of the destabilizing factor on the generator so that the frequency drift tends to zero as the temperature changes. Temperature-compensated quartz oscillators are highly stable and have a short readiness time. However, to create generators with a frequency stability of ± 0,1 ppm, imported components are required, which makes their production difficult in modern conditions.
A technological chain is created at the JSC «LIT-PHONON», which allows producing a quartz resonator using only Russian components. The goal is to use these resonators in temperature-compensated oscillators with frequency stability of ± 0,1 ppm. However, the analysis showed that the resonators have problems with frequency drift over time during operation at a maximum operating temperature of + 85 ºС. Additional adjustment of generators during operation is required. It is also revealed that some Russian components are not ideally suited to the developed technological process, which may negatively affect the yield of suitable products. The measuring setup also has an error of ± 0,5 ppm, which does not allow an accurate assessment of the frequency stability of the resonators.

The article proposes a new method for measuring frequency based on a one-bit ADC. In contrast to the known method of measuring frequency using a delay line, the developed structure of a meter that implements the proposed method makes it possible to get rid of delay lines for measuring frequency in a wide frequency range and to sharply reduce the weight and size parameters of the entire meter with an integrated implementation. Unlike other known digital meters, described in sources, the proposed method makes it possible to increase the accuracy of frequency measurements in a wide frequency range.

Using of existing methods of determining the characteristics of soils which are part of current regulatory documents and which are based on the hypothesis of normal character of distribution require considerable time and material costs. According to the results of conducted laboratory researches the hypothesis wasn’t confirmed. In the paper it proposes to use trained artificial neural network for determination of the deformation modulus of binary composite «sand — granules of expanded polystyrene». Thus, it has been proven efficiency proposing method using trained artificial neural network in compare classical regression equation for determination of the deformation modulus of the binary composite. With a confidence probability of P = 95 % the absolute value of the relative error is equal to 11,8 % the proposing learning artificial neural network in 11 times less than the absolute value of the relative error of classical regression equation. Also with a confidence probability of P = 95 % the coefficient of determination is equal to 0,5641 and in 6,6 times less than it of regression equation. Further research will be directed to the selection of the values of the parameters of the artificial neural network program for increase the accuracy of determining the deformation modulus of the binary composite.

The article is devoted to the analysis of compressibility factor calculation methods in the temperature range from 220 to 250 K. The AGA8-92DC (GOST 30319.2- 96), AGA8 Report Detail (GOST 30319.3-2015), GERG-2004/2008, NX19, GERG-91, ISO 20765-1 (GOST R 8.662-2009), GSSSD MR 118-05 (moderately compressed gas mixtures) and GSSSD MR 113-03 (Wet Oil Gas) methods are experimentally tested. Deviations of experimental data and calculated values of compressibility coefficient determined by the specified methods are shown. It is found out that the deviation of the calculated values of the compressibility factor according to the AGA8-92DC, AGA8 Report 1 Detail, GERG-2004/2008, ISO 20765-1 (GOST R 8.662-2009), GSSSD MR 13-03 methods from the experimental ones does not exceed 0,1 %. This fact confirms the possibility of using these methods in the temperature range from 220 to 250 K. The results obtained in the framework of this study are highly significant for flow metering, and in particular, provide an increase in the accuracy of the procedure for bringing the volume of natural gas to standard conditions at low temperatures.