Vol 28, No 1 (2020)

Informatics, Computer Science and Control
Software implementation and research of the system for intellectually adaptive management of the enterprise information infrastructure
Basinya E.A.
Abstract

The paper describes the problems of information and communication interaction of technical objects and systems. The vulnerabilities of the TCP / IP protocol stack, the imperfection of operating systems and application software, the complexity of full mutual integration of various systems are analyzed. The consequence of saving vendors of network solutions on computing power in the form of architectural constraints and vulnerabilities is described. The design, software implementation and experimental study of the author’s system of intellectually adaptive management of the enterprise’s information infrastructure, which operates on the basis of the previously presented method of the same name, is considered. A modern technology stack is used in combination with a flexible development methodology. The scientific novelty of the work lies in the proposed architecture of a comprehensive software product for managing the enterprise information infrastructure. Improving the efficiency, reliability, security and fault tolerance of the operation of technical objects and systems is achieved by using the automation platform for deploying and managing applications in a multi-layer virtualization environment. Isolation of work services is carried out with the ability to automatically restart any component without violating the normal operating mode of the infrastructure. A number of restrictions inherent in existing solutions, such as the number of simultaneously supported VPN connections, as well as defined policies and rules are removed. Increasing the level of confidentiality of network interaction, as well as countering anonymous unauthorized disturbances, is achieved by full integration with overlay technologies and networks, and also by supporting a wide range of modern cryptographic encryption algorithms with the possibility of multi-layer encapsulation. In order to evaluate the effectiveness of the developed system, an experimental comparative analysis is presented with various existing solutions: comprehensive firewalls, routers, intrusion detection and prevention systems, as well as other traffic management tools.

Vestnik of Samara State Technical University. Technical Sciences Series. 2020;28(1):6-21
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Operative mathematical modeling of electrotechnical and metallurgical industries of the samara region
Burtsev A.V., Yevelev A.L., Kachalin V.P.
Abstract

The paper deals with the problems of forecasting the macroeconomic processes using mathematical modeling, namely the Cobb-Douglas production function, for the effective management of the sectoral policy of enterprises in metallurgical and electrical industries of the Samara region. An operative mathematical modeling that does not require great computational resources was carried out. It also allows repeatedly predicting the results of managerial decisions in practice. The impact of the number of employees and their salaries on the output in these sectors is considered. During the study period, the authors built models both taking into account scientific and technological progress and without it. The verification of the models obtained was carried out using the coefficient of determination, as well as the Fisher test, Student t-test, and Darbin-Watson criterion. The conclusions were made about the quality of the constructed models.

Vestnik of Samara State Technical University. Technical Sciences Series. 2020;28(1):22-33
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Analysis of properties of probabilistic moments of binary sequences for stochastic objects modeling
Keznetsov V.M., Pesoshin V.A., Gumirov A.I., Shirshova D.V.
Abstract

The applicability of the statistical method for determining the significant homogeneity of binary sequences under probabilistic moments of any finite order for solving problems of mathematical modeling of stochastic objects is proved. Approaches to the construction of the homogeneity criterion in the framework of various ways of setting probabilistic moments are described. Significant differences in the decomposition of central probabilistic moments into raw ones for systems of random events of a homogeneous nature and concerning sequences are revealed. Brief theses of methods for finding the critical length of samples within which binary sequences have significant homogeneity over the specified raw or central probabilistic moments are presented. Areas of application of the concept of homogeneity of random sequences in theoretical statements of problems of machine implementation of mathematical models and practical development of means of adequate comparison of statistical characteristics of stochastic objects are determined.

Vestnik of Samara State Technical University. Technical Sciences Series. 2020;28(1):34-48
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Automated control system for technological process of extrusion line for communication cables production
Mitroshin V.N., Sviridov K.O.
Abstract

The new approach and method of controlling the imposition of insulation in the manufacture of high-frequency wired communication cables of high regularity, ensuring the achievement of the required characteristics of the products was proposed. The main tasks are formulated when automating the technological process of imposing insulation with extrusion lines. Discrete systems have been developed to stabilize the pressure in the cable head of the extruder and stabilization of the polymer melt temperature in the dosing zone of the extruder has been developed. The analysis of the work of the systems for stabilization of the operating parameters of the process equipment carried out using computer simulation proved their high efficiency.

Vestnik of Samara State Technical University. Technical Sciences Series. 2020;28(1):49-61
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About methods of actors knowledge visualization in intersubjective management of problem situations solving
Moiseeva T.V., Mukhanov Y.S.
Abstract

The paper deals with the specifics of intersubjective management of problem situations solving where actors are employees of socio-technical objects. The difference between traditional management of socio-technical objects and intersubjective one is shown. The importance of the subject is explained by the fact that the result of actors’ problem situations solving could be the basis for the further development of innovative products manufactured by socio-technical objects. The difference between the role of people-subjects of the problem situations and people-objects is shown. The importance of decision-making management methodology creation in the subject - subjective relations is noted. It is proposed to supply the methodology of the intersubjective management theory with methods of actors’ knowledge visualization. Therefore, the purpose of this paper is to discover existing methods of knowledge visualization as the means of mental processes enhancing, and to select some methods that could support and facilitate the actors decision-making process. Two cognitive mechanisms lying in the basis of actors’ knowledge presentation are considered. It is shown that figurative thinking based on spatial-structural relationships lies in the basis of the creation of problem situation visual images. The main visualization methods used in management are considered. The “periodic” table proposed by Ralph Lengler and Martin J. Eppler, where all methods are divided into six groups (data visualization, visualization of relationships, concept visualization, strategy visualization, metaphor visualization and compound visualization), was chosen as the basis for visualization methods systematizing. The author’s analysis and detailed description of these methods were carried out, supported by examples of various visualization tools application. Cognitive visualization methods for representing the knowledge of actors has been selected. For each stage of problem situations solving process the proper units from different groups of methods of the "periodic" table are proposed.

Vestnik of Samara State Technical University. Technical Sciences Series. 2020;28(1):62-73
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Comparative evaluation of computer equipment efficiency in the departments of industrial enterprise
Uchaykin R.A., Orlov S.P.
Abstract

The paper considers the task of assessing the effectiveness of computer equipment used in the design and design departments of a large engineering company. It is shown that the variety of tasks to be solved, the difference between computer configurations and departmental staff makes it difficult to identify functional links between the efficiency criteria and the characteristics of computing. It is proposed to use the analysis method of the operating environment - Data Envelopment Analysis, which allows to conduct a comparative analysis of heterogeneous production units and determine the directions of achieving the specified performance. The article proposes a system model of the company's department. The model takes into account the following parameters of units and computer equipment: the number of employees, the number, the item and performance of computers, the total cost of computer equipment, the specific amount of tasks performed in the department. An analysis of the mutual influence of different entrance and output parameters has been carried out. Non-performing units have been identified and the targets for their parameters are set to further improve efficiency. During the biennium, with the use of the Malmqvist index, progressive departments and departments in which the efficiency of computer technology decreased were identified. Graphs and diagrams of the units in the question are presented under different conditions. Conclusions on providing units with new computer equipment and reallocating resources have been drawn.

Vestnik of Samara State Technical University. Technical Sciences Series. 2020;28(1):74-86
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Electrical Engineering
Application of STATCOM for voltage regulation in power systems using the bat search algorithm
Alekhin R.A., Kubarkov Y.P.
Abstract

Modern energy systems are characterized by a dynamic change in all their constituent components: a large number of industrial consumers appear, regular work is done to commission new or modernize old equipment, and new concepts for creating and managing energy systems are being developed. With increasing loads, system losses increase, and the voltage profile in all nodes of the power system becomes much worse. Electrical energy is constantly lost in electrical networks at transmission and distribution levels. Power losses in the distribution network due to a lower voltage level and a higher ratio of active resistance to reactive compared to the level of transmission networks are more significant. In addition, power losses force electric plants to generate more active and reactive power, which leads to increased fuel use and higher tariffs for the end user. In this situation, the use of traditional methods to find optimal operating conditions for energy systems becomes ineffective. Heuristic and then metaheuristic optimization methods that are able to find a solution close to the global optimum have gained the greatest popularity for solving such problems. The article presents a solution to the problem of optimizing voltage levels in the power system using the bat search algorithm and compares the results obtained with the particle swarm optimization algorithm. This method showed higher optimization qualities, which indicates its applicability for solving such problems.

Vestnik of Samara State Technical University. Technical Sciences Series. 2020;28(1):87-99
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Modeling of deformation processes in a valve
Bazarov A.A., Bondareva N.V.
Abstract

A set of issues on computer modeling of valve deformation processes at lower temperatures are reviewed in the publication. Some types of valves which are used to shut off fluid flows are exposed to jamming. The problem relates to valves with a solid rigid wedge. It is often show up with temperature drop down to negative values. The valve electric drives have enough power, thus combining with the presence of gearboxes it creates a force, that sometimes leads to a breakage of the valve stem on the opening process. The purpose of the work is to define the influence of geometric and physical parameters in the valve on the development of deformations and thermal stresses resulting in jamming. To determine the jamming cause, an analysis of various options was made. The options include the occurrence of deformations of structural elements which are associated with the processing technology of the adjacent surfaces of the wedge and saddle, using various materials, and calculations of the deformation processes for some simple structures were performed. Mathematical modeling was performed using the finite element method. Due to the slow change in ambient temperature, stationary three-dimensional models were used for calculations. The temperature change is set in the issue through the fixed differential. The design features of valves with a hard wedge require careful machining to ensure a tight fit and eliminate leaks. Due to the complexity of access to the internal cavity of the valve for processing, a collapsible design is provided, which allows to achieve high quality surfaces and to avoid jamming. The use of different grade steels and the possibility of surface hardening during machining leads to a difference in physical properties such as coefficient of thermal expansion. However, according to the calculations, with the small thickness of the parts and the hardening depth, the influence of coefficient of thermal expansion isinsignificant. Another reason for the difference in strain is the difference in elongation of the rod and the cylindrical shell. In the given temperature range for materials with low coefficients of thermal expansion, the difference in the geometric measurements turned out to be low and comparable with the calculation error. The study of the geometric shape influence on the relative deformations of the valve elements demonstrated that the use of cylindrical shells and continuous cylinders in the design do not lead to the development of thermal stresses. Even the shape of the wedge does not affect the magnitude of the deformations. However, the production of the vertical part of the body in a conical shell shape leads to the appearance of significant deviations in the deformation magnitude of the mating surfaces. In the actual valves, the body has a more complex shape, but the size ratio corresponds to the simplified model considered before. Conclusion: to avoid jamming, the design must be symmetrical. Since this solution is more material-intensive, it is required to equip the valves with heating systems to balance deformations.

Vestnik of Samara State Technical University. Technical Sciences Series. 2020;28(1):100-113
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Analysis of existing methods of voltage regulation within the framework of developing questions of creation of the centralized system of automatic voltage regulation
Rakhaev A.V.
Abstract

The prevention and elimination of emergency conditions, as well as the reduction of energy losses in electric networks are urgent tasks. The solution of these problems, in some situations, is directly related to voltage regulation. Improving the reliability of the electric power system, equipment of power plants and substations, as well as reducing losses in electric networks, require optimal voltage regulation. Due to the constantly changing circuit-and-mode situation in electric power systems, the high workload of the dispatching and operational personnel, especially during the repair campaign, the need to take into account a number of factors that affect the operating mode of the electric power system, voltage regulation by dispatching and operational personnel is «manually», necessary automation of the process of voltage regulation in electric networks.

The article discusses the current principles of voltage regulation in the electric network of the Unified Energy System of Russia, outlines the main practical tasks related to voltage regulation. To solve these problems, it is proposed to create a special regime automation, namely, a centralized system for automatic voltage regulation. The structure and operation algorithm of a centralized system for automatic voltage regulation are described.

The implementation of a centralized system of automatic voltage regulation in the Unified Energy System of Russia will reduce energy losses, as well as ensure acceptable voltage levels according to the requirements of the quality of electricity and working conditions of insulation of electrical equipment and prevent (eliminate) unacceptable current overloads of power lines and equipment in cases where the implementation of this tasks using existing tools are difficult. The implementation of such automation also allows to relieve dispatching and operational personnel.

Vestnik of Samara State Technical University. Technical Sciences Series. 2020;28(1):114-128
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Articles
To 115-th anniversary of Longin Frantsevich Kulikovsky
Lange P.K., Karganova O.G.
Abstract

To 115-th anniversary of Longin Frantsevich Kulikovsky

Vestnik of Samara State Technical University. Technical Sciences Series. 2020;28(1):129-131
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To 115-th anniversary of Vitaly Nikolaevich Nikolsky
Barsova A.A.
Abstract

To 115-th anniversary of Vitaly Nikolaevich Nikolsky

Vestnik of Samara State Technical University. Technical Sciences Series. 2020;28(1):132
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