The article discusses various mechanisms of self-healing of concrete used in the construction of buildings and structures designed for certain operating conditions and the environment, which saves resources and time during maintenance and repair of objects for various purposes. Types of self-healing of concrete: With hollow fibers; Microcapsulation; Expanding additives; Bacteria. Conclusions. Today, progress has been made in understanding the relationship between the structure of materials and their properties. Thanks to the knowledge gained about the structure of materials, the possibility of designing materials of directional quality was considered, which guarantees their compliance with certain operating conditions and the environment.

Keywords: concrete, destruction, self-healing, hollow fibers, microcapsulation, expanding agent, bacteria

The article provides statistical data on the age composition of Russian scientists; describes the financial capabilities of students in non-budgetary graduate school, including those related to the possibility of defending dissertations; ways of restoring the continuity of scientific generations in the Russian Federation are proposed.

Keywords: postgraduate study, age composition of scientists, virtual research institutes, organization of scientific research, scientific generations, continuity

The possibilities of using modern information technologies in teaching graphic disciplines in the conditions of the spread of coronavirus infection (COVID-19) are considered.

Keywords: engineering, graphic disciplines, COVID-19, information technology

The article describes the architectural techniques used in the process of developing case studies for assessing the professional skills of students, implemented as part of the educational process of the RSTU. The decision to use the interface as the center of architecture is justified. Possible problems in the process of developing the interface of the specified software are described, and ways of solving them are also presented. Thanks to the presented methods of building the project architecture, you can get rid of the main drawbacks associated with the dependence of the program code of the implemented product on the user interface. Increase the scalability and reliability of the application, while maintaining the overall quality and functionality.

Keywords: interface, user interface, architectural solution, loaded interface, software, pattern, messagebroker, coroutine, pseudo-stream, case

The study is devoted to the generalization of the existing world experience on the impact of recycled polyethylene terephthalate (PET) products when they are added to concrete on its characteristics. Analysis of the available data shows the effectiveness of the use of PET fiber in a concrete matrix in order to recycle plastic waste, facilitate concrete structures, save cement consumption and improve the strength characteristics of concrete. But the researchers did not come to a consensus on the effective consumption of fiber during reinforcement, the influence of the shape of the fibers used on the properties of fiber concrete, as well as the areas of application of this material.

Keywords: concrete, concrete matrix, fiber, dispersed reinforcement, polyethylene terephthalate, tensile strength, compressive strength

The article presents the results of studies on the influence of sintering modes on the distribution of carbon in the material of a porous powder billet used for the manufacture of a differential satellite by dynamic hot pressing. The distribution of carbon and density in the satellite material is established, recommendations for its chemical and thermal treatment are given.

Keywords: dynamic hot pressing, heating temperature, powder billet, density, satellite, sintering temperature, cementation, quenching, material property

A periodic semiconductor structure is considered, consisting of tunnel-uncoupled quantum wires (QW) based on InSb containing impurity centers. The uniform magnetic field is directed along the QW axis. For the case of light polarization transverse with respect to the QW axis in the framework of the dipole approximation, in the effective mass approximation, an analytical expression for the impurity absorption coefficient of light is obtained taking into account the dispersion of the QW radius described by the Gauss function. It is shown that on the spectral curve constructed in the Maple program, for given parameters of the QW and the semiconductor structure, there is a sequence of resonant maxima with a doublet structure. The cyclotron frequency determines the distance between the maxima in the doublet, and the frequency of the doublets on the spectral curve is determined by the hybrid frequency. With an increase in the magnetic field, the dynamics of the edge of the impurity absorption band is observed, which can be used to create detectors of optical radiation in a wide range of wavelengths and will make it possible to identify such semiconductor structures. It is also possible to obtain valuable information about the parameters of the QW and the band structure of the semiconductor from the spectral curve

Keywords: impurity absorption coefficient, quantum wire, low-dimensional semiconductor structures, impurity center

The system for measuring cargo dimensions is designed for streaming measurement of cargo dimensions, which can be luggage at airports and transshipment bases, various parcels, as well as commercial cargo. The authors of the article developed a structural and functional diagram of a control and measuring system for dynamic measurement of cargo dimensions, and also considered the principles of its operation.

Keywords: control and measuring system, measurements, cargo dimensions, luggage, automated systems

Internet of Things (IoT) technologies are widely used in many fields today, including the power engineering. This article describes the development of a hardware and software complex for collecting and storing thermometry data. Related works are considered. The complex includes the data collection and transmission module and the database on the server. Measurement indicators are collected and transmitted using the Arduino Uno platform. For temperature measuring, the thermocouple is used, the normalizing converter converts the signal from the thermocouple. The signal gets to the input of the ATmega328 microcontroller of Arduino Uno platform. Data transmission is carried out wirelessly by EPS-12 microcontroller using the MQTT application layer protocol and Wi-Fi channel protocol. The database was implemented using the MySQL database management system. The developed software and hardware complex is used for steam boiler condition monitoring at the thermal power plant of the Moscow Power Engineering Institute.

Keywords: measuring device, thermocouple, Arduino, Wi-Fi, MQTT, publisher, broker, subscriber, Internet of things, MySQL, database, thermal power plant

In this paper, a study was made of the test device for voltage stabilizers Teplocom ST-222/500, ST-555, ST-888. The DUT provides the verification algorithm outlined in the setup, verification, and process run instructions. This test involves changing the phasing of the conductors at the input of the device under test; control of voltage sources supplied to the tested stabilizer; measurement of voltage values ​​at the input and output of the stabilizer; their registration. The aim of the work is to design a device for testing voltage stabilizers, with an error of the measuring unit of not more than 2.5% and a test speed of at least 1.3 s. To confirm the achievement of the specified parameters, simulation was carried out in the MicroCap 11 software package.

Keywords: voltage stabilizer, MicroCap, Teplocom, transient simulation

This work presents a simulation of a hexagonal membrane. Some partial solutions for the problem of free vibrations of a membrane of regular hexagonal shape with a different initial bending of the surface are obtained and the natural frequencies of vibrations are found. The result obtained can be used in modeling wing structures in the form of a hexagon of such aircraft as a paraglider.

Keywords: Modeling of a hexagonal wing, free vibrations of a membrane, a membrane of a regular hexagonal shape, natural frequencies of vibrations

The article presents the results of a study of the stepper motor control system of a road printer. The use of a stepper motor imposes additional requirements on the road printer in terms of operating parameters control. The main requirement for the stepper motor of the road printer is to ensure the rotation of the rotor, at a given angle, which depends on the control mode. The description of the road printer is given. The dependencies of the stepper motor as a control object are given. Investigated for the stability of the Nyquist system. A simulation model of the stepper motor control system of a road printer has been developed and simulation results are presented.

Keywords: road printer, stepper motor, mathematical model, transfer function, modeling, controller

This article discusses the features of the processes of heat and mass transfer, taking into account the formation of the contact surface during the interaction of air and water droplets sprayed in the working space of the spray chamber. The results of numerical modeling of heat and mass transfer processes are presented, which made it possible to establish the conditions of liquid atomization that ensure the most efficient flow of heat and moisture exchange processes in the working space of the spray chamber.

Keywords: air handling unit, spray chamber, heat and mass transfer, diffusion model, efficiency, droop parameters, calculation model, numerical simulation

The article considers one of the ways to improve the reliability of mining equipment, by eliminating sudden failures and reducing the severity of their consequences, based on the use of digital technologies and automated control systems for its technical condition and online diagnostics. It is proposed to use the methods of diagnostics and automated control of the technical condition of power electrical machines, which consist in monitoring the current with subsequent spectral analysis of the recorded signal. The method allows to determine the current technical condition of the engine elements with sufficient accuracy. A high-performance RISC microcontroller of the AVR ATmega16 family was adopted as the constituent elements of the diagnostic complex, which contains a fast Harvard processor, program memory, data memory, input / output ports and various interface circuits.

Keywords: reliability of mining equipment, diagnostics, automated control, current monitoring, spectral analysis

The article presents the results of checking the adequacy of the method of online diagnostics and automated control of the technical condition of the electromechanical drive of the KP21 mining machine with an asynchronous squirrel-cage motor, proposed earlier by the authors. The method of experimental production studies provides for the connection of the measuring complex to the stator winding of one of the phases of the electric motor. The measurements were carried out under various operating conditions of the combine, corresponding to various technical conditions of the facility. A comparative analysis of the technical condition of the diagnosed nodes and the values ​​of the normalized amplitudes of the corresponding frequencies led to the conclusion: the defect must be fixed if the signal amplitude exceeds the value of 10% of the maximum, and the defect is significant and needs to be eliminated if the amplitude value exceeds 30%. To use the obtained research results in practice, an integral nomogram of the correspondence between the operating time of the combine harvester and the amplitude - frequency characteristic of the stator current of the drive motor of the cutting body is proposed. The results obtained are taken as a basis for correcting the schedule of preventive maintenance and maintenance of the cutting body of mining machines KP21 when operating in the appropriate mining and geological conditions.

Keywords: reliability of mining equipment, online diagnostics, automated control, current monitoring, maintenance and repair

The paper considers a structural model of a solid body. Yu. N. Malashkin proposed a structural model of concrete, the main idea of ​​which is an elementary volume in the form of a polyhedron formed from rod octahedra. When developing the model, only its analytical analysis was carried out. In this work, in the development of the model, its finite element analysis was carried out in the LIRA-SAPR software package. The study showed the coincidence of the qualitative and quantitative parameters of the model obtained by numerical and analytical calculations, confirmed its adequacy in relation to concrete.

Keywords: structural model, concrete, elementary volume, polyhedron, rod octahedron, finite element analysis, lira-sapr software package

The article presents an overview of the work on modeling the behavior of a double electric layer in membranes under influences of various nature, including the example of various surface phenomena (adsorption, surfactants, adhesion, wedging pressure, electroosmosis, etc.). It was noted that the size and distribution of the charge over the surface near which it is formed has an effect on the structure of the DES; to obtain the potential distribution, it is necessary to know the structure of the membrane-electrolyte solution interface; it is intermediate to be able to calculate the charge distribution, and, accordingly, to calculate the potential distribution itself. It was pointed out that when choosing a mathematical interpretation of the process, the Poisson equation is often used, taking into account the self-consistent field, or the Navier-Stokes equations are solved together with the Nernst-Planck equation and the electroneutrality condition; the Gui-Chapman model is used to describe processes with low accuracy by molecular dynamics methods, supplemented by the ion adsorption condition according to the Langmuir isotherm; when modeling the electrolyte current, the description of the surface current of ions is used, taking into account the viscous properties of the medium.

Keywords: double electric layer, zeta potential, membrane, primembrane layer, spatial charge density, Navier-Stokes equation, surface current, Poisson equation, capacitor, fluid flow potential

With the development of wearable technology, unique opportunities have emerged for providing user interaction and highly accurate personalized recognition of his work activity. The purpose of this study is to propose methods for taking into account the evaluation of the economic efficiency of human resources using big data and machine learning methods, which will allow making more informed decisions in the process of human capital management. The article proposes an approach using a hybrid neural network CNN-LSTM, aimed at determining the specific type of work performed by specialists, providing the ability to control the execution of these actions based on data from wearable devices (smart watches, smart bracelets). The accuracy of the developed algorithm in recognizing 18 different types of actions on the test sample was more than 90% according to the Accuracy metric (the proportion of correct answers).

Keywords: human capital, labor productivity, hybrid neural network, convolutional neural network, recurrent neural network

The article discusses the possibilities of GIS technologies for assessing the spatial and temporal distribution of forest fires in the European part of Russia. An analysis of the variability of data on both forest fires and climate data for the same long-term period and on the same regional scale was performed. General trends and main fire hazards have been identified that will help in the future, in the presence of reliable climate scenarios, to make decisions on prevention strategies and more effective fire management.

Keywords: forest fires, geoinformation systems, analysis, climate, spatial distribution, effective management

This article gives an overview of the operation of dehumidification plants located in indoor ice arenas. Since at the moment the operation of such facilities does not include control of such parameters as CO2 content, the possibility of implementing this task using the existing equipment is considered. A method of setting the automatics of maintaining the CO2 level in the set parameters is given. The principle of dehumidifier operation and problems of CO2 level control are considered. The method of tuning the control loops is also described. The use of CO2 controlled dehumidifier equipment will create comfortable conditions for the occupants of the ice arena, which in turn will lead to a reduction in energy and heat consumption.

Keywords: automatic control system, control loop, control object, process stabilisation, air drying, air drying plant

The article deals with the problem of studying the functioning of the document management system under unauthorized influences, the relevance and practical significance of which is due to the peculiarity of the requirements for ensuring the protection of confidential information, and the significance of damage in case of disruption of the uninterrupted flow of documents circulating in the system. To model the processes of functioning of the electronic document management system, an approach based on the use of the apparatus of Petri-Markov networks is proposed, which allows taking into account the statistical nature of the processes of receipt of documents for processing and manifestations of impacts from intentional threats to information security. Within the framework of the proposed approach, a model of the functioning of the electronic document management system under the influence of ARP-spoofing attacks, which are a common type of threats to information systems in the public administration sphere, has been developed. At the same time, the options for the impact of threats in the absence of technical means of information protection and their application are considered. The constructed model can be used when conducting computational experiments to determine the most effective means of information protection of electronic document management systems.

Keywords: electronic document management system, unauthorized impact, simulation modeling, Petri-Markov networks

To ensure the correct and continuous operation of all electronic devices, it is necessary that all components of these devices correspond to their declared characteristics. In this article, an information-measuring system for incoming control and analysis of the quality of components is being developed. Structural and functional diagrams of the system were developed. A natural experiment was carried out.

Keywords: information-measuring system, input control, quality analysis, components