The article considers the solution of the urgent problem of calculating the size of the effective focal spot of a microfocus X-ray tube using computer modeling methods. The principle of operation of the calculation method used by the authors is to compare interference images obtained using tested microfocus X-ray tubes with simulated interference patterns formed using the developed software by numerically solving the wave equation. It should be noted that modeling a one-dimensional interference pattern using fast Fourier transform requires a significant amount of RAM and takes considerable time even when using modern computer equipment. The paper presents the results of modeling phase contrast profiles for two types of test objects – nylon fishing line and aluminum wire. The considered method for determining the size of the focal spot is characterized by good sensitivity and allows efficient and high-precision calculations for all types of microfocus X-ray tubes.

Keywords: computer modeling, X-ray tube, microfocus source, focal spot, non-destructive testing

This research presents the methods and conclusions obtained from modeling a composite wall panel with a wooden frame and polystyrene concrete core in the Lira-SAPR program, used in the construction of low-rise buildings for residential and commercial purposes. The findings were compared with the results of panel tests at the research laboratory of the Pacific State University (hereinafter TOGU).

Keywords: linear calculation, panel construction, low-rise construction, LIRA-SAPR, modeling

Indentation is a universal and practical method for obtaining material characteristics, especially when it is impossible or difficult to expose the material to other measuring methods. Experimental data on the mechanical properties of various types of materials were obtained using the shock loading unit. A mathematical model based on the finite element method was used to verify the experimental results. The article considers the solution of the problem of classification of neural metals with different mechanical properties. As part of the work, an artificial neural network has been created that allows the distribution of materials into selected groups. It is determined that a significant advantage of using neural networks is the ability to process experimental data and identify complex nonlinear dependencies, which makes them in demand in tasks related to the study of material properties.

Keywords: impact indentation, neural network, task of classification, artificial intelligence, dynamic indentation, non-destructive testing.

The article presents calculations of energy costs when carrying out major renovations of a building. Based on the obtained values, the structure of fuel and energy resources expenditures by subgroups of repair and construction work was formed. The presented research results are based on the calculation and comparison of the obtained energy consumption values ​​in proportional units - kilograms of standard fuel. As a result of the study, the highest energy consumption was established, which is accounted for by the consumption of liquid fuel in comparison with electricity, which is due to the specifics of the machines and mechanisms used (truck crane, truck, etc.), as well as the chosen technology of repair and construction work. In order to account for and minimize energy costs during the period of major repairs, it is also proposed to monitor the consumption of fuel and energy resources.

Keywords: diversification of management, production diversification, financial and economic purposes of a diversification, technological purposes of ensuring flexibility of production

Vulcanization is a technological process that transforms plastic rubber into rubber. As a result of vulcanization, the shape of the product is fixed, and the material becomes more durable, hard and elastic. The purpose of the article is to determine the effect of octyl phenol-formaldehyde resin on the vulcanization parameters and to identify its optimal amount for the development of vibration-absorbing materials based on butyl rubber. The effect of a vulcanizing agent (octyl phenol formaldehyde resin) on the properties of the rubber compound during vulcanization was established. As a result of the study, the kinetics of vulcanization and the effect of various components on the properties of the rubber compound, such as elongation at break, conditional tensile strength and specific damping ability, were studied. This study is conducted in order to find the optimal rubber for placement in a seismic damper used in buildings and structures.

Keywords: vulcanizing group, vibration absorbing material, butyl rubber, rubber compound, vulcanization, octyl phenol formaldehyde resin, seismic damper

The issues of atmospheric pollution, including noise pollution, are considered. The dependences of the concentration of carbon monoxide at distances from the roadway at different directions and speeds of the wind flow obtained according to MRR-2017 are presented. The influence of motor transport on the condition of the air basin and the health of the urban population is considered. The levels of noise pollution in the main-line territories of Volgograd, as well as the main pollutants in the atmospheric air of the main-line territories, are considered. The dispersion of CO concentration at different wind speeds at different angles of wind direction to the road and traffic noise levels depending on the days of the week, time of day, and traffic flow intensity are considered.

Keywords: wind flow direction and speed, roadway, atmospheric air, mainline territories, traffic noise levels, carbon monoxide concentration, vehicle fleet, cargo flow

Bar structures are widespread in construction due to their economy, freedom of design shapes and sizes. As a result, automation of design and calculation of such structures is an urgent task. As part of the study, the task of developing a software module that generates a map of optimal cutting of rolled metal based on the results of calculations of rod structures has been implemented. The algorithm under consideration takes into account such features of the cutting optimization problem as taking into account the width of the blade, the possibility of using half the size of the rolled product, support for optimization of several sections, and welding of parts in case the length of the workpiece is exceeded. The software module is developed using JavaScript and C# languages. The ability to automatically generate cutting maps based on the results of optimization of rod structures increases the efficiency of designing building structures.

Keywords: Design in construction, bar structure, computing system, web development, design in construction, rod structure, computer system, web development, optimal cutting, rolled metal, cutting map

The article discusses standard models of titanium dioxide-based memristors. A memristor is similar to a memory resistor and demonstrates a nonlinear resistance characteristic in which the charge parameter is a state variable. They can be used to create new types of electronic devices with high energy efficiency and performance, as well as to create machines that can learn and adapt to changing environmental conditions and in many practical applications: data storage memory (binary and multilevel), switches in logical electronic circuits, plastic components in neuromorphic artificial systems intelligence based on nanoelectronic components. It has been shown that when voltage is applied to charged ions, they begin to drift, and the boundary between the two regions shifts. When a sinusoidal alternating voltage of a given frequency is applied to the memristor, the shape of the volt-ampere characteristic (VAC) resembles a Lissajous diagram centered at the origin.

Keywords: memristor, model, voltage characteristic, nonlinearity

Roads occupy an important place in the life of almost every person. The quality of the coating is the most significant characteristic of the roadway. To evaluate it, there are many systems, among which there are those that analyze the road surface using video information streams. In turn, the video is divided into frames, and the images are used to directly assess the road quality. Splitting video into frames in such systems works based on special software tools. To understand how effective a particular software is, a detailed analysis is needed. In this article, OpenCV, MoviePy and FFMpeg are selected as software tools for analysis. The research material is a two-minute video of the road surface with a frame rate 29.97 frames/s and mp4 format. The average time to get one frame from a video is used as an efficiency indicator. For each of the three software tools, 5 different experiments were conducted in which the frame size in pixels was consistently increased by 2 times: 40000, 80000, 160000, 320000, 640000. Each program has a linear dependence of O(n) average frame retrieving time on resolution, however, FFMpeg has the lowest absolute time indicators, as well as the lowest growth rate of the function, therefore it is the most effective tool compared to the others (OpenCV, MoviePy).

Keywords: comparison, analysis, effectiveness, software tool, library, program, video splitting, frame size, resolution, road surface

Currently one of the promising trends in the global energy sector is the introduction of renewable energy sources (RES) into the existing grid. The use of RES can be favourable in autonomous power systems where fuel costs are high. However the stochastic nature of power generation creates a number of difficulties in maintaining the power balance. To solve this problem, it is proposed to connect a hybrid energy storage system (HESS) consisting of a battery and a supercapacitor to the load busbars. The efficiency of such HESS depends mainly on the way of its connection to the grid and the choice of control method. The article gives an overview of the existing mechanisms for controlling the power consumption of HESS.

Keywords: Renewable energy, hybrid electricity storage, power converter topology, electricity storage control strategy

When studying the problems of water filtration to a single horizontal imperfect drain of finite length, in a system of interacting horizontal imperfect drains, it is necessary to consider spatial (three-dimensional) filtration problems. Unlike flat (two-dimensional) problems, spatial filtering has been studied in less detail, since it is difficult to obtain rigorous solutions to their problems.

Keywords: water supply facilities, filtration, equipotentials, drainage, borehole, pressure reservoir, drain, pressure, inflow, reservoir, watercourse

The work is devoted to an urgent problem - the development of automated process control systems for the production of bricks with improved characteristics. The purpose of the article is to define and systematize the tasks of automation of brick production control systems, to develop both an algorithm for managing brick production and a generalized structure of automated control systems for brick production, and the tasks of the work are: optimization of control automation levels that determine the generalized structure of automated control systems for brick production, determination of information collection subsystems corresponding to the stages of brick production, and development of their structures, the choice of basic measurement tools for information collection subsystems. The results of the work are: systematization of requirements for modern automated process control systems, development of an algorithm for controlling technological processes and a generalized structural scheme of automated process control systems for brick production, development of information collection subsystems for the developed automated process control system, development of the structure of a local automated process control system in brick production - brick drying. The developed technical solutions can be recommended for control automation in various industries.

Keywords: brick production, technological process, drying, firing, control algorithm, automated control system, structural scheme, information collection subsystem, single-channel circuit, multi-channel circuit, measuring circuit, four-arm bridge circuit

The article considers the requirements of regulatory documents to ensure fire safety during construction and operation of gas distribution pipelines in Russia and China. The different approach to fire risk reduction in the two countries is revealed: more specific and stringent requirements in China and general requirements related to fire hazardous facilities in Russia.

Keywords: fire risks, fire regulations, natural gas combustion, causes of natural gas fires, natural gas transportation, fire safety

The paper presents an overview of the task of automatic text summarization. The formulation of the problem of automatic text summarization is carried out. The classification of algorithms for automatic text summarization by the type of the resulting summary and by the approach to solving the problem is carried out. Some existing problems in the field of automatic text summarization and disadvantages of certain classes of algorithms are described. The concepts of quality and information completeness of the summary are defined. The most popular approaches to the assessment of the information completeness of the summary and their classification in accordance with the methodology used are considered. The metrics of the ROUGE family are considered in relation to the task of automatic text summarization. Special attention is paid to the evaluation of the information completeness of the summary using such metrics of information proximity as the Kulback-Leibler divergence, the Jensen-Shannon divergence and the cosine distance (similarity). The metrics mentioned above can be applied to the text vector representations of the initial text and summary. The text vector representation in question can be performed using such methods like frequency vectorization, TF-IDF, static vectorizers and so on.

Keywords: automatic summarization, summary, information completeness, ROUGE, vectorization, TF-IDF, static vectorizer, Kullback-Leibler divergence, Jensen-Shannon divergence, cosine distance

The large-scale development of Russia's lands led to the creation of a railroad network. Along with the laying of the railroad, the entire transportation infrastructure, such as bridges, tunnels and overpasses, was erected. Many structures are already more than 100 years old. The structures are deteriorating and approaching the end of their life cycle. It is therefore necessary to reconstruct or dismantle these structures. Due to the increased freight traffic between China, Russia and Western Europe, it is necessary to reconstruct all tunnels on the BAM. This paper presents one of the tunnel reconstruction options and investigates by mathematical modeling the stress-strain state of the system "array-construction" by which the tunnel can be reconstructed.

Keywords: mathematical modeling, stress-strain state, railway tunnel, reconstruction, finite element method, drilling and blasting, mechanized tunneling, mining machine, displacements, Baikal-Amur Mainline