The article considers the issue of measuring and controlling the parameters of a high-voltage AC circuit using a Bragg grid. A model of a fiber-optic sensor based on the magnetostriction effect, the main component of which is a fiber-Bragg grating, is proposed. The 3D modeling of the magnetostriction process and the design of the block diagram are carried out.

Keywords: optical fiber, magnetostriction, bragg grid, AC, sensor, solenoid, coil, nickel, ferrite, MathCAD, COMSOL

This article discusses a proportional-integral-derivative controller circuit for an unstable system with a delay in a parallel control structure. The parallel control structure has two separate controllers for tracking tasks and suppressing load disturbances. The considered controller is developed on the basis of a direct synthesis approach by choosing a separate reference model with feedback. The proposed design method is applicable to both the lower and the high-level unstable process without model reduction in the higher order process. The effectiveness of the proposed method is demonstrated through example modeling and comparison with methods published in the literature.

Keywords: proportional-integral-derivative regulator circuit, direct synthesis, reference model, design method

A model for assessing the consumer attractiveness of commercial real estate objects is described on the example of assessing the quality of sports and entertainment centers in the city of Perm. In the course of the study, a sociological survey was conducted to identify the factors that influence the choice of consumers of a sports and entertainment center to visit. The results of the survey became the information base for the model of assessing the quality and consumer attractiveness of the studied objects. Two approaches to the definition of quality were compared – the mechanism of complex assessment and the qualimetric model.

Keywords: commercial real estate management, sports and entertainment centers, integrated assessment mechanisms, management efficiency, quality of commercial real estate, consumer attractiveness, probability of choice, decision trees, convolution matrices

In this article, the object of study is the drying of plant products in a combined drying apparatus using infrared radiation, convection and reduced pressure. The process of drying products in the food industry is still relevant today in connection with the optimization of efficiency and reduction of energy consumption. In the presented experimental study, the following products are used: apples, bell peppers, bananas. The slice thickness varies from 5 to 10 mm. Observations show that, with optimal parameters and drying modes, the possibility of using the described drying installation is fully expedient.

Keywords: drying, infrared radiation, reduced pressure, convection, dried food, pilot plant

The article deals with the priority passage of regulated intersections by public transport using the method of extending the permitting signal. The relevance of the problem under consideration is due to insufficient study of the issue of choosing the optimal control parameters for the method of extending the resolving signal. Using simulation modeling, a study was carried out of the priority passage control process on two- and three-lane road sections. In the course of the experiment, the dependences between the extension time of the allowed signal and the cycle duration were determined at different ratios of the phase coefficients, as well as the optimal distance of the priority activation detectors. The obtained results of the research work can be used in the design of the urban intelligent transport system and when adjusting the control modes in the automated traffic control system of the urban agglomeration.

Keywords: priority movement of urban passenger transport, transport detectors, intelligent transport systems, simulation, traffic light control parameters

The peculiarities of implementation of the process of digital transformation of the enterprise are considered. The structure of a digital balanced system of indicators is proposed, including a strategic map of digital transformation, key success factors and performance indicators. The conceptual structure of enterprise digital transformation management is given.

Keywords: digital transformation, strategic map, key performance indicator, key success factor, risk, management solutions, balanced scorecard, simulation model, strategy

This article uses the structural-functional method. The proposed study shows how many factors influence the performance, efficiency of enterprises and how important it is to follow the latest technologies and vectors of their development. Everything is important, from the material and technical equipment of personnel to the timely replacement of obsolete or outdated devices that have reached the limit of their own reliability. No reliance should be placed solely on technical means or personnel performance - these two crucial aspects must work together, be continuously monitored and have everything they need to perform their tasks in a quality and timely manner. It is also important to learn from the experience of previous years, so that it is possible to understand what mistakes have been made and, therefore, to act appropriately in order to avoid them again. It is also important to develop such positive trends as the transition to remote control of relay protection devices. To date, we must pay special attention to information security of the complexes' operation during the transition to remote control, as the current realities of work at power facilities require exactly that. Equally important is the purpose of this article to forecast future trends in RPA development over a period of twenty years.

Keywords: relay protection and automation, improvement of the regulatory framework, introduction of relay protection

The results of a study of the influence of slags from various manufacturers on the spreadability, strength and shrinkage of self-compacting fine-grained concrete are presented. It was found that replacing up to 30% of cement with slag reduces the strength of concrete only in the initial period of hardening. It was shown that the use of slag can significantly reduce the shrinkage of concrete.

Keywords: granulated blast furnace slag, mineral additive, fine-grained concrete, self-compacting concrete, mixture flow, strength, shrinkage

When designing security systems for buildings and structures, the technical specification specifies the required characteristics of the equipment. On the basis of the technical specification, a certain number of solutions (projects) from different designers and suppliers can be formed. These projects may differ in equipment, method of installation and maintenance, different degrees of functional reserve and the possibility of expanding the system if necessary. At this stage of equipment selection, the engineer is faced with the problem of choosing one optimal option from the presented subset, since all projects (solutions) meet the requirements of the technical specification. The presented algorithm for selecting the elements of the security system of real estate objects is based on the construction of a complex assessment model. The characteristics by which the equipment will be compared are determined. The degree of importance of each characteristic is determined. A comprehensive assessment of each alternative is calculated. The proposed approach avoids the negative consequences of subjectivism arising from the influence of the external environment.

Keywords: multi-criteria task, algorithm, selection task, security system, ranking, design, terms of reference, criterion, complex evaluation, model

The article deals with the case when a concentrated force is applied to the web of a prestressed beam. The preliminary shear stresses do not affect the stress state in the middle of the beam span. However, preliminary normal stresses will act over the entire height of the wall and affect the distribution of the zone of local stresses and the stress state of the web. Determination of stresses in a beam is based on the beam theory of S.P. Timoshenko. The article presents a system of equivalent forces on the edges of the wall and the equation of normal stresses in the cross section of a prestressed beam. Compared to a conventional beam, prestressing reduces normal stresses from concentrated forces.

Keywords: thin-walled structure, steel beam, I-beam cross-section, prestressing, local stresses, local effect, Saint-Venant principle, Timoshenko SP beam theory, Karman's solution, Fourier integral, stress function

In the automation of production, the use of robots is an important direction. When developing algorithms for controlling the movement of such a machine, multidirectional problems arise. In a critical situation, the robot must not harm workers or collide with its fellow robot. At the same time, the car must move along the optimal route. The article analyzes the methods of finding optimal paths on square navigation grids. The wave method on undirected planar graphs, the A* algorithm (an extension of Dijkstra's algorithm), and the D* Lite algorithm for graphs with non-constant or previously unknown structure were chosen for the analysis. A visualization and testing system in C#has been developed for the research and testing of algorithms. The system is implemented using the Microsoft Visual Studio 2019 IDE software tools and external GraphX and Emgu CV libraries. A unique feature of the system is the ability to directly read images of shop floor maps in widely used graphic formats and automatically convert them to a format that is understandable to the system. First, the user uploads the shop floor plan. For easier processing, the image is converted to two colors: black and white. Then the image is processed by the Emgu CV library, at the output we get all the contours of stationary obstacles. Then, depending on the size of the robot, an orthogonal navigation grid is superimposed. The analysis of the obtained results allows us to conclude that it is better to use a method (the D* Lite algorithm) that allows for a non-constant or unknown grid structure in advance.

Keywords: visualization, program, graphic format, work, shop, map, square, grid, cell, navigation, optimal route, planar graph

The article provides an assessment of the economic efficiency of a prestressed bistal beam, prestressed stretching of web. The comparison is made with a conventional bistal girder without prestressing with the same cross-section. The costs of material, design, production, transportation and installation are considered. It is taken into account that to create pre-stress, more labor costs are always needed, therefore, the manufacture of pre-stressed structures is more expensive than conventional structures. The purpose of prestressing is to reduce the consumption of steel in the fabrication of the structure. The structure of labor costs for the manufacture of structures is given. A comparative analysis of the cost "in business" of a running meter of a beam, prestressed by wall stretching, and a beam without prestressing, depending on the complexity of their manufacture, is carried out.

Keywords: thin-walled structure, bistal girder, I-beam, prestressing, stretching of web, structure weight, overhead costs, labor intensity of manufacture, cost-effectiveness, custom design, value in action

This article provides information on the possibility of using offshore wind farms to provide energy to offshore structures such as oil and gas platforms, as well as coastal communities.

Keywords: wind power plant, wind generator, offshore power plant, SIEMENS generator, offshore oil and gas facility, oil and gas field, coastal settlement

Crushed stone-mastic asphalt concrete is a more durable material compared to traditional asphalt concrete. But for its exploitation, high-quality mineral powders and bituminous carriers are needed to prevent bitumen from flowing out of the composition. Today, the carbonate rock powders and bituminous carriers from natural cellulosic fibers are widely used. However, many Russian Federation regions, including the Krasnoyarsk Territory, are not provided with these materials, and they are also really expensive. The purpose of our work was to reduce the cost and improve the properties of crushed stone-mastic asphalt concrete. The task of the research was to develop gravel-mastic asphalt concrete compositions using the industrial waste from the Krasnoyarsk Territory. Nepheline sludge was tested which is the waste of the alumina plant in Achinsk and rubber crumb with inclusions of cord fiber of Chernogorsk in Krasnoyarsk Territory. The chemical composition and physical and mechanical properties of these wastes were studied. Gravel-mastic asphalt concrete compositions were made by using these wastes. The tests showed that the received compositions met regulatory requirements. The developed compositions were introduced by “Krasnoyarskavtodorom” on the Krasnoyarsk Territory roads. The economic effect of the waste usage is achieved through the exploitation of the local raw materials, which leads to a reduction of the transportation and energy costs.

Keywords: the crushed stone-mastic asphalt concrete, industrial waste, nepheline sludge, mineral powder, bituminant, rubber waste with corded fiber inclusions, crushed stone, sand Crushed stone-mastic asphalt concrete, industrial waste, nepheline sludge

The article analyzes the results of experimental studies of prestressed steel I-beams. Presented specific features of the stressed and deformed states of welded steel beams, prestressed by wall stretching and bending of the initial T-element. In the first method, the prestressing in the beam was created by mechanical stretching of the wall on a special stand. In the second method, the T-piece is loaded by external forces applied to the T-bar plate until normal stresses appear at the bottom point of the wall, equal to the design resistance of low-carbon steel, then the second belt plate is welded to the T-piece element. The results of a numerical experiment with these beams, carried out in the SP LIRA, are considered. Presented a comparative assessment of the results of numerical and full-scale tests of prestressed I-beams a similar section with bimetallic beams without prestressing.

Keywords: web stretching, T-beam bending, section asymmetry, numerical experiment, test stand, stress, bearing capacity, beam rigidity, bending deformation, local stability