bluuebunny/crossref_metadata_2025 huggingface dataset:
Methodology of the selection of effective dipping and control over the filling depth of open-textured construction materials
Authors: Nikolaev SV , Benin AV , Popov AM
Published: December 2021

It is determined that for the combination of the dipping process with the ultrasound control it is necessary to carry out the optimization of the filling speed and the precision of control over the dipping depth, to determine the optimum frequency of the ultrasound emission which satisfies the speed and the dipping measurement precision of the sample with the hydrophobic agent. On the basis of the performed multiobjective optimization, experimental results for the dipping and the control over the dipping stage of porous materials by the solution in the uniform acoustic field alignment charts are received for the selection of the rational frequency of ultrasound fluctuations which allow regulating and/or optimizing dipping and control processes over the material filling depth subject to customer tasks. The selection methodology of effective values of parameters of the acoustic field providing the combination of filling processes and the control over the depth of the dipped material filling is well-reasoned.
Thermodynamic acceleration of two-phase layered flows in channels with permeable walls of MGD-generators
Authors: Kim K K
Published: December 2021

When creating MHD (Magnetohydrodynamic) alternating current generators using liquid-metal working body, the latter is accelerated by piston method, in which the working body is a periodic structure of alternating zones of liquid metal (pistons) and zones of compressed gas, the latter is accelerated liquid-metal pistons. This raises the form stability problem for liquid metal pistons. Viscous frictional forces generated inside the pistons lead to the destruction of the pistons and significantly reduce the efficiency of the MHD unit. One solution is to use gas-permeable walls of the channels of MHD-generators, through the pores of which gas is injected. In this way, the piston flow is isolated from the side surface of the channel by the penetrating gas in the channel cavity. As a result, friction losses are drastically reduced. At the final values of the One solution is to use gas-permeable walls of the channels of MHD-generators, through the pores of which gas is injection coefficients, (? ≥ 0.03)the friction practically disappears. With the channel length determined by the coordinate of the maximum piston speed, 92% of the current marginal efficiency values can be achieved. The maximum efficiency of the runaway channel can be achieved by selecting the optimal value of the air injection coefficient. The operation of the devices commutating the injected gas must ensure that there is an injection in an area that is no more than twice the length of the piston.
Problem statement for the analysis of electromechanical systems by simulation modeling methods
Authors: Kim K К , Ivanov S N
Published: December 2021

The article presents an approach to the complex analysis of electromechanical systems using specialized packages of applied simulation programs. It is shown that the choice of research methodology is due to the complexity and mutual influence of energy processes in electromechanical converters and the absence of verified analytical solutions.The main research stages are defined, including the construction of a geometric model of the object, determination of the problem type to be solved and relevant initial and boundary conditions, justification of defining criteria, modeling of electromagnetic, thermal and hydraulic processes and their analysis. The software packages are based on the classical equations of electrodynamics, heat transfer, energy, motion and continuity. Creation of three-dimensional solid parametric model is implemented in the T-FlexCAD system. The simulation experiment was carried out with the use of SolidWorksFlowSimulation system, that allows to process the initial array of design parameters in conditions of the multiphysics problem statement. The variables were ranked using Statistica, a statistical processing and data analysis program. Simulation results of energy exchange processes at varying geometry of defining design parameters allow to establish dependence of electromechanical system output characteristics on design and dimension relations of system elements parameters and to design high-efficiency electromechanical systems on this basis.
The risk-based strategy model technical maintenance of the unique technological structures
Authors: Mironov A , Soldatenko V , Soldatenko T
Published: December 2021

The article considers an approach to the development of a risk-based strategy model for the technical maintenance of a unique technological structure. It is proposed to use the minimum risk of the structure failure as a criterion for optimizing the technical maintenance of the structure. It is shown that this approach allows to decrease considerably and by limited means the risk of the elements failure especially those influencing the structure safety. The task of determining the strategy parameters of technical maintenance of the construction object under consideration is formulated as a Boolean mathematical programming task. The theoretical conclusions are confirmed by the calculation example. The solution showed the advantage concerning the risk of use of the proposed strategy in comparison with the current one.
Acoustic emission control of tensile and compression defects for plastic carbon fiber samples reinforced with side girders
Authors: Stepanova L , Chernova V
Published: December 2021

Tensile and compression tests of composite samples made of carbon fiber reinforced with side girders have been carried out. It was found that the area of active location of acoustic emission (AE) signals corresponds to the destruction of the composite, bolted and glued joints. Destruction of the carbon fiber-reinforced plastic material did not always occur in the area of the fasteners, but the sources of AE signals with the maximum total amplitude were registered in the destruction zones.
Modeling the convective thermal heat transfer of nanofluids with carbon nanotubes in cylindrical minichannel
Authors: Rudyak V , Minakov A , Guzey D
Published: December 2021

This paper is devoted to the development of an algorithm for numerical modeling convective thermal heat transfer of nanofluids with carbon nanotubes. The algorithm is based on a one-liquid description of a nanofluid with common macroscopic variables. The properties of the nanofluid are determined only by the concentration of carbon tubes, and it is assumed that their distribution is uniform and does not change during the flow. A nanofluid can have both Newtonian and non-Newtonian rheology. The fundamental point of this algorithm is the need to use real thermophysical data in solving specific problems, which depend on the concentration of carbon nanotubes naturally. The transport equations are solved using finite volume method. The algorithm was tested by comparing the simulation data with the experimental. The problem of convective thermal exchange of nanofluid with single-walled nanotubes is solved. The corresponding experimental data were previously obtained by the authors of this work. It is shown that the algorithm simulates the considered flow with high accuracy. In addition, its important advantage is the possibility of modeling the flow characteristics, which cannot be measured experimentally. As such example the data on the velocity and temperature profiles of the fluid in the channel are presented.
Theoretical background for simulation of physical processes in the interfacial layer “solid-liquid”
Authors: Ignatyev A A , Gotovtsev V M , Gerasimov D V , Provatorova G V
Published: December 2021

The paper shows a modification of the quasi-thermodynamic approach to simulation of the interfacial layer from conditions of its mechanical equilibrium. The anisotropy of the interfacial stress tensor is represented as the sum of the ball and deviator parts, where the ball part defines the pressure in the medium and the deviator part forms the components responsible for the liquid surface tension. Obtaining a closed system of equilibrium equations was possible taking into account evaporation from free surface of liquid. The result is a simple expression for determining the thickness of the interfacial layer.
Study of the working process of a diesel engine with modified fuel
Authors: Yur G , Nosonova E
Published: December 2021

The research objective is to reduce specific fuel consumption and emissions of exhaust fume pollutants. Specifically treated (modified) fuel is used to comprehensively improve the economic and environmental performance of the diesel operation process. Fuel treatment was carried out at a pilot plant using the process of fuel gas cavitation. During processing, high-molecular fuel compounds were broken down and the fuel was saturated with gas-vapor bubbles. The description of the pilot unit is given. The characteristics of the base distillate and modified fuel are studied. A mathematical model and the numerical study results of the fuel droplet development containing vapor-gas bubbles are presented. An experimental study of the work process in a 10.5/12 H diesel engine single-cylinder compartment when operating on various fuels was carried out. Diesel tests have shown that when using modified fuel, the specific indicative fuel consumption has decreased by 5-7 per g / kWh, the exhaust gas temperature has decreased by 5-8 degrees, the concentration of nitrogen oxides in the exhaust fumes has decreased by 32-46 ppm, the concentration of total hydrocarbons has decreased by 9-14 ppm, the smoke content has decreased by 1.2-1.7 times.
Airborne noise calculation for single-layer partitions with the concentrated parameters method
Authors: Zakharov A V , Saltykov I P
Published: December 2021

The article considers an approach to the calculation of sound insulation for building partitions with the method of concentrated parameters at the standard frequency range, which is specified in regulatory documents. The concepts of “reduced” and “concentrated” masses are introduced for objects that are sound conductors. It is noted that the physical model of sound insulation in the three conditionally allocated frequency ranges of the standard spectrum has differences. The calculated equations of sound insulation for three frequency ranges are given. Systems of equations for obtaining the calculation formulas at the first and the second frequency ranges are used. The systems consist of equations for the conservation of the amount of motion and the conservation of kinetic energy. The influence of the damping effect of air and resonant phenomena in the plate on the final value of sound insulation is described. The nature of sound propagation in the third frequency range is considered, in which, unlike the first two sections of the frequency spectrum, where the propagation of flexural waves is mainly recorded in the plate, shear and dilatational vibrations have a predominant influence on the sound insulation level. Examples of graphs for massive partitions obtained by the considered method are given. The accuracy of the proposed method is evaluated in comparison with the normative code’s method and the method based on the theory of self-matching of sound fields. A general algorithm for calculating sound insulation in the entire standard frequency range is presented.
Modification of Anshel-Anshel-Goldfeld Postquantum Algorithm / Protocol Based on Algebraic Braid Groups, in Order to the Span–Cyberattack Neutralization
Authors: Baev D A , Cherckesova L V , Safaryan O A , Kravchenko V O , Razumov P V
Published: December 2021

This article deals with relatively young field of cryptography, namely cryptography based on the theory of infinite abstract groups. The research identifies the main problems on which this type of cryptography is based, and the cryptoanalysis conducts of one of the algorithms grounded on the problem of mating (conjugate) element finding, on the base of which the protocol for common key generating is developed. As the algorithm under study, the protocol for generating the common key based on Anshel-Anshel-Goldfeld algorithm, built on the algebraic braid groups, is investigated. During the study of this protocol, one of possible cyberattacks was identified, which allows to get hold of the secret keys of subscribers. To eliminate and to neutralize this span–cyberattack, the new modification of Anshel–Anshel– Goldfeld (AAG) algorithm was developed, which significantly reduces the probability of this cyberattack successful implementation. Analysis of this modification operating time was carried out also.
Solution of boundary value problems with moving boundaries by using an approximate method for constructing solutions of integro – differential equations
Authors: Litvinov V L , Tarakanov A V
Published: December 2021

The problem of oscillations of objects with moving boundaries, formulated as a differential equation with boundary and initial conditions, is a non-classical generalization of a problem of hyperbolic type. To facilitate the construction of a solution to this problem and justify the choice of a solution form, equivalent integro-differential equations are constructed with symmetric and time-dependent kernels and integration limits varying in time. The method for constructing solutions of integro-differential equations is based on the direct integration of differential equations in combination with the standard replacement of the desired function with a new variable. The method is extended to a wider class of model boundary value problems that take into account the bending stiffness of an oscillating object, the resistance of the environment, and the rigidity of the substrate. Particular attention is paid to the consideration of the most common in practice case when external disturbances act at the boundaries. The solution is made in dimensionless variables accurate to second-order values of smallness with respect to small parameters characterizing the speed of the border.
Automatic segmentation of the borders of the pathological focus in the macular area of the retina to calculate the area of the pathological focus
Authors: Filippenko V A , Bondarenko U F , Dolgov V V , Epikhin A N
Published: December 2021

Optical coherence tomography (OCT) is a modern, non-contact method of diagnostic examination that enables the visualization of various tissues of the human eye in a cross-sectional view at the microscopic level with the required morphological information. The software pre-installed in such devices contains many different tools for analyzing scans and has almost all the functionality necessary for the doctor to make a correct diagnosis. However, as time passes, more and more advanced methods of analyzing the images appear, which actualizes new tasks of developing additional software that can supplement and expand the functionality of the diagnostic equipment. This paper proposes an algorithm for automatic segmentation of the borders of a pathological focus in the macular area of the retina to calculate the area of the pathological focus, which together with other algorithms for analysis of morphometric parameters of the human eye, which are still under development, will be used for more accurate diagnosis of the stage of age-related macular degeneration.
Deanonymization of users based on correlation analysis
Authors: Boldyrikhin N V , Altunin F A , Svizhenko A A , Sosnovsky I A , Yengibaryan I A
Published: December 2021

The article discusses the issues of deanonymization of network users who hide their data in order to evade responsibility when committing malicious acts. Within the framework of this work, a user deanonymization algorithm has been developed based on traffic correlation analysis. The algorithm is based on comparing the statistical characteristics of traffic generated by an unknown user with the characteristics of traffic corresponding to known users. An illustrative example of the implementation of the algorithm, which confirms its effectiveness, is given.
Wavelet filtering for solving the problem of selecting the outlines and analysis of the measurement results in the background of noise
Authors: Shvidchenko S , Zhukovskiy A , Tkachuk E
Published: December 2021

Currently, the issue of developing new modern algorithms and methods is quite relevant, which will allow in an automated mode to analyze images (signals and the results of their measurements) against a background of noise. This task is relevant in the analysis and modeling of dynamic processes and objects, in the search for methods for automating their control. For the process of automating the processing of the results of computational experiments, it is important to implement the calculation of the derivatives of the first and second order against the background of noise.
Promising directions for the development of modern databases
Authors: Kalayda Alexey V
Published: December 2021

In this article, we will compare the SQL and NoSQL models, their advantages and disadvantages, clarify the variations of using both approaches to database management and explain in which cases it is better to use one or the other model. Three main characteristics of the system were tested: parallel data processing, working with information stores, and data replication. The possibility of parallel data processing was evaluated by analyzing the mechanisms of blocking, multi-level parallel access control and ACID. Storage testing covered both physical media and RAM usage. Replication was tested in synchronous and asynchronous modes. During the tests, we found out that SQL databases with the possibility of clustering showed promising performance results per node and also have scalability.
Intellectualisation of the decision support system by a multiagent robotic system based on neural network technology
Authors: Ivanov S V , Kotelnitskaya L I , Khorolsky E M
Published: December 2021

The article considers the process of forming management decisions for the correct operation of a multi-agent robotic system (grouping of unmanned aerial vehicles (UAVs)) in a rapidly changing conditions. A neural network (NN) is used as a regulator, which is a perceptron with two intermediate layers, one is input and the other one is output. The training of the constructed neural network is carried out according to an algorithm that combines the ideas of the conjugate gradient method with quasi-Newtonian methods, and in particular, uses the approach implemented in the Levenberg-Marquardt algorithm. As input parameters for building a control system, various types of situations are used in which the UAV leader has to make decisions. Such initial data are a three-dimensional data structure, which is a two-dimensional array, each element of which is a vector. One vector reflects all available information about the situation in certain geographic coordinates (weather conditions, data on other damaging factors affecting the ability of the UAV to operate in a certain area), and the other describes the current state of the UAV (power reserve, weight, operability of components and assemblies, term of next service, etc.). The obtained information is put down into the input layer of the NN by numerical equivalents. The paper proposes a situational work model of a UAV group in special conditions.
Mathematical experiment as a tool for modeling the freight transportation process
Authors: Bogachev V A , Kravets A S , Bogachev T V
Published: December 2021

The process of multimodal freight transportation on a railway loop is investigated, for which a multicriteria optimization model with time indicators is created, which is a nonlinear integer programming problem. The developed approach is based on egalitarian and utilitarian principles in the welfare theory and allows (along with Pareto optimal transportation plans) to find other plans that can be considered rational from the point of view of maintaining the balance of interests of the transportation process participants. A mathematical experiment is an effective heuristic tool in research. The algorithm for solving the optimization problem is implemented in the environment of a computer algebra system and brought to numerical results.
Method for assessing the operating quality of a switching node in a technological transmission network data in the context of DDoS attacks by an intruder
Authors: Privalov A A , Lukicheva V L , Tsvetkov D N , Titov S S
Published: December 2021

The purpose of this study is to develop a mechanism to account for the effects of a distributed denial of service attack on a switching node, as well as to assess the quality of its functioning under destructive effects. Relevance stems from the possibility of disruption of regional economic complex management due to the impact on the elements of the technological network of data transmission attacker type “distributed denial of service”. Based on the mathematical apparatus of GERT-networks the authors propose an approach to assess the quality of switching nodes. The essence lies in the representation of the data flow service node switching network data transmission under attack by an intruder in the form of a stochastic network, setting the type of partial distributions, the definition of the equivalent function, followed by determining the distribution function delay time packets. The model proposed by the authors allows to evaluate the quality of switching nodes operation under the conditions of “distributed denial of service” intruder attacks, both when transmitting stationary Poisson and self-similar traffic, represented by the Weibull and Pareto flow models. The results obtained are in good agreement with the data given in previously published works. The model allows to analyze and develop directions to improve the quality of functioning of switching nodes of technological network of data transmission under conditions of destructive information impact of the intruder.
Offline character recognition in transport logistic tables
Authors: Yu Bursian E , Demin A M
Published: December 2021

The paper proposes the improved skeleton method of handwritten characters recognition, which is based on the filtering procedure and the principle of alternating shading schemes of skeletonized area on the 4- and 8-timeslinked raster. The procedure of high-frequency filtration based on discrete real cosine transformation or discrete complex Fourier transform with automatic selection of filtration parameters makes it possible to significantly improve the image quality of handwritten symbols, in particular, to eliminate in many cases thin bridges between the areas of symbol element representation. The principle of alternating the painting schemes along the 4- and 8-timeslinked raster makes it possible to get the wave front of the skeletonized area close to a circle. In this case, the broken lines representing the branches of the skeleton graphs retain the shapes of the symbols. Numerical experiments on the construction of skeleton sets and skeleton graphs for recognizable handwritten symbols located in the cells of the tables of logistic transport problems have been performed. Software implementation of the method is proposed.
Search for potentially dangerous constructs in the source code of the program using neural networks
Authors: Zelensky A , Cherkesova L , Revyakina Ye , Korochentsev D
Published: December 2021

This work is devoted to the study of artificial neural networks to search for potentially dangerous constructs in the source code of the program. A modification of the existing analyzer programs is proposed for a better search for vulnerabilities in software. The use of neural networks will allow programmers and analysts to find those vulnerabilities that have not yet been added to the database. As a result of the research, it was found that the use of neural networks to identify specified constructs is a more effective solution than searching through a database of vulnerabilities, since it allows you to identify not only those constructs that are in the database, but also suspicious code sections.
On the comparison of two approaches to intersectoral balance analysis
Authors: Obrosova N , Shananin A , Spiridonov A
Published: December 2021

The diversification of the inter-industry connections of modern economies seriously hindered the analysis of production networks evolution and input-output balances projection, that traditionally was made by the Leontief Input-Output balance model. That is why the new approaches have begun to develop, that take into account the substitutability of products and services in modern supply networks. In this work we discuss the quality of the new approach to the intersectoral linkages analysis, that is based on the nonlinear model of resource allocation with Cobb-Douglas production technologies. We compare this approach with the traditional Leontief’s scheme of intersectoral connection studying. We make evaluations using the both of methods for large economies, that are on different stages of economic development.
Correction of the model dynamics for the Northern seas using observational altimetry data
Authors: Belyaev K , Chetverushkin B , Kuleshov A , Smirnov I
Published: December 2021

The earlier derived data assimilation method called Generalized Kalman filter (GKF) is applied in conjunction with the Nucleus for European Modelling of the Ocean (NEMO) circulation model to the calculation of the dynamics in the North Seas of Russia. By assimilating the satellite altimetry data from archive AVISO (Archiving, validating and interpolating of satellite observations) this method corrects the direct model calculations and improves the ocean state. The model fields, in particular, sea level and sea surface temperature with and without assimilation are constructed and compared with each other. The brief analysis of the results is also performed.
Change in the amplitude of strong discontinuity wave propagating in a rod made of Murnaghan material
Authors: Major M , Major I , Yazyev B
Published: December 2021

The paper presents calculations of the change in amplitude of strong discontinuity wave propagating in a thin rod made of hyperelastic Murnaghan material. Two functions were assumed for the calculations, describing the change of the cross-section of the rod with the constant scaling parameter?for both decreasing cross-sections of the analysed steel rods. A numerical analysis was performed based on analytical solutions. The analytical form of solution for both rods with decreasing cross-sections allowed for preparation of contour maps for the propagating wave of strong discontinuity. Furthermore, the changes in the relative amplitude of the propagating shock wave in a thin rod were determined for two rods analysed in the study, for which the differences in the values of the relative amplitude in the final cross-section were found.
Features of using a two-point crossover for solving an inhomogeneous minimax problem modified by the Goldberg model
Authors: Kobak V G , Porksheyan V M , Jukovskiy A G , Shkabriy R S
Published: December 2021

The relevance of the topic of this work is the strong growth of multiprocessor systems, for which it is important to solve a large volume of tasks in a minimum time. There are various algorithms for solving such a problem, which can be divided into classes of exact and approximate. The representative of approximate algorithms is the algorithm of the Goldberg model, which gives acceptable results, the modifications of the crossovers of which are studied in this paper.
Properties of prime numbers and their relation to sound vibrations
Authors: Pinevich Elena , Agishev Timur , Belyakov Yefim , Gargatsova Svetlana
Published: December 2021

The article introduces new properties of prime numbers. An alternative method for finding prime numbers using linear algebra tools is discussed. The probabilistic approach is used to analyze the use of a new property as a means of finding prime numbers. Mathematical calculations of determinants composed of prime numbers were converted to sound according to a given pattern. To optimize the process of calculating and converting numbers to, a software implementation was performed. A MIDI format saved in a folder has been created. In the process of processing the received data, the program recorded a melody, which, when changing scales, gives a beautiful sound.
Compiler for physical and geometric construction of sets
Authors: Pinevich Elena , Mayorov Denis , Safaryan Olga , Lagunova Elena , Fisenko Konstantin
Published: December 2021

This article is devoted to the geometric representation of sets. The paper presents an implementation that allows using operations on sets to build any images. For this algorithm, the equations of first-and second-order lines on the plane and first-and second-order surfaces in space are used. Restrictions are introduced by setting segments on the coordinate axes, indicating whether lines or surfaces belong to these segments. Inequalities are used to create the shaded area of the drawings. In the course of research on this topic, a software tool was developed that allows you to model drawings using the entered formulas, build images based on a set of operations on given sets of points, which allows you to have an analytical description of the drawings. This software tool can be used both in the educational process to test the correctness of the assimilation of the material, and to create flat geometric shapes and three-dimensional bodies for the purpose of engineering the optimal forms of structures and various parts. This application allows the user, performing operations with mathematical expressions and inequalities, to get a graphical display of the result with a mathematical description of any part of the figure.
The execution complexity of logical formulas with restricted quantifiers based on CF-grammars
Authors: Korovina K S , Sh Rudova I
Published: December 2021

The polynomial realized formulas are introduced with quantifiers acting on hierarchy lists described by CF-grammars. Upper estimates of execution complexity are obtained depending from the sort of grammar. These formulas have been applied for formal definition of context-dependent syntax of programming languages and describing dynamic discrete system.
On randomized Cobb-Douglas production function
Authors: Neumerzhitskaia N V , Saifutdinova N A , Solokhin N N , Volosatova T A
Published: December 2021

The paper considers a Cobb-Douglas function with n random elasticities. A theorem on the concavity and strict concavity of such a function is proved.
Strict convexity of the objective function and uniqueness of the maximum point in a model with three arbitrary random priorities
Authors: Pavlov I V , Neumerzhitskaia N V , Uglich S I , Volosatova T A
Published: December 2021

The main result of this paper is the proof of the strict concavity of some function of integral form depending on three random variables, which we call priorities. This function is an objective function in the so-called model with priorities, in which the arbiter, following expert opinions, distributes funds among the enterprises and institutions under his jurisdiction. This result implies an important corollary about the existence and uniqueness of a local maximum point (which is also a global maximum point) of the objective function. This is a significant generalization of the corresponding result of N.V. Neumezhitskaia, S.I. Uglich and T.A. Volosatova, published in December 2020.
Logic prototyping: approach and use cases
Authors: Il’icheva O A , Ilicheva V V
Published: December 2021

In this article, we present an approach to prototyping complex systems and processes using classical predicate logic. The prototype is built by the interpreter based on a logical description of the properties and/or behavior of the designed system. The description contains the definitions of the prototype elements and the constraints that the correct prototype must satisfy. Definitions are used to build a prototype, and constraints are used to analyze it and check the required properties. Definitions are interpreted using direct logic inference, constraints are only checked on the resulting model. A wider class of formulas is used than in well-known logical languages. Computable logical and denotational semantics are defined for them. In the process of building a prototype, logical errors of uncertainty, redefinition of functions, and contradictions are diagnosed. We are given examples of prototype descriptions used for semantic program analysis, space training, transport system design.
Increasing the contact line operational reliability by forecasting its constructive elements’ failures
Authors: Bodrov P A , Popova N A , Ganashek A L
Published: December 2021

The article discusses the issues of calculating the indicators of the power supply systems’ reliability. The analysis of the existing problem and options for its solution are given. To assess the patterns, the authors proposed a mathematical tool. The method based on the rectangular scores’ technique is adopted as a forecasting method. The development belongs to the class of specialized method-oriented software tools.
Simulation modelling of operational tests to assess the reliability of railway automation software systems
Authors: Maslov A A , Maslov An A
Published: December 2021

A simulation model for in-servicetesting of software reliability assessment for railway automation systems is described in this paper. As a basic concept, the reliability indicators are calculated using the concept of a reference object, being the most common element of the respective train protection systems on the road network. We are aware that this concept is embedded in the subsystem for the formation of the reference object-element infrastructure of JSC “Russian Railways”, involving the function of bringing all track, electrification and power supply facilities as well as automation and telemechanics facilities to the reference objects. In order to develop this approach, the “Performance Test Simulation” application was developed on the Windows Presentation Foundation (WPF) platform, using the object- and component-oriented programming language C#, allowing the practical simulation of performance tests of reference objects of various types, during the design phase, using the Monte Carlo method.
Algorithms for forming the coefficient matrix of a system of differential equations Chapman-Kolmogorov models of non-stationary service systems
Authors: Bubnov V P , Sultonov Sh Kh
Published: December 2021

The paper considers a new approach to building models of nonstationary service systems based on: the formation of all possible states of a nonstationary service system with a finite number of applications and rules of transition between them; the formation of the coefficient matrix of Chapman-Kolmogorov differential equation system; the numbering procedure for all states. A critical analysis is made of the algorithms for the formation of the coefficient matrix and the numbering procedure for all states: sequential, recursive and recursive with grouping. Its comparison with the recursive algorithm is given, as well as the optimal structure for storing the list of states for the sequential algorithm. Recommendations for the practical application of software implementations of the considered algorithms are discussed. Theoretical foundations for building and calculating models of nonstationary service systems have been developed. It is compared to the recursive algorithm. The optimal structure for storing the list of states for a sequential algorithm is given.
Processing of strain gauge control signals by the Kalman filter
Authors: Vyplaven V , Kolomeets A , Popkov A
Published: December 2021

One of the methods for detecting defects in the rolling surface of the wheels of freight cars is to measure the deformations of the rail under the passing train. The method is based on the analysis of a strain gauge signal. The main task of the strain gauge signal analysis is the selection of informative components and the removal (filtering) of interference. The paper presents methods of filtering diagnostic signals of strain gauge control and the selection of informative components. The useful signal component can be used to measure the mass of cars, to determine the dynamic load on the rails and to detect defects in the rolling surface of the wheels. The method of adaptive Kalman filtering and linear convolution are proposed as signal processing tools. Based on these algorithms, a software module based on the.NET Framework has been developed using the C# programming language. The algorithms were tested on the signals received when the train was moving along the active section of the track, with a strain gauge control system located on it. The computational complexity and speed of the algorithms are assessed, and the possibility of their further application in the autonomous mode of the system is investigated. The results show that the use of the Kalman filtering algorithm provides a significant performance advantage over the linear convolution algorithm.
Degree estimates of one class cut-offs for improper integrals
Authors: Pozhidaev A , Khaustova O
Published: December 2021

The paper considers a normalized non-integral integral of the first kind with a variable lower bound. In this case the integrand is a generalization of the standard Gaussian distribution density. Such integrals are often called cutoffs or incomplete functions. The purpose of this paper is to obtain power inequalities for this kind of integrals. The necessity of obtaining this type of estimations is due to the fact that incomplete functions have become widespread in applications and theoretical studies. The peculiarity of the results established in the article consists in the fact that arbitrary degrees of a given integral for any value of an argument are evaluated from above not by means, of the value of integrable functions at a certain point, but by the value of the integral in question at some point proportional to this argument. The coefficient of proportionality, a parameter, can take any value from some closed interval. The main difficulty in obtaining these inequalities is that the integrand is a logarithmically concave function, that is, its logarithm is a concave function. The paper also proves that both limits of the closed interval for the parameter cannot be extended. This shows that the obtained estimates are unimprovable.
Study of the soil stability theory problems by the simplex method
Authors: Karaulov A , Nemtzev D , Konkov A , Shekhov V
Published: December 2021

The questions of linear programming methods application to the main problems of stability theory - problems on slope stability, problems on ultimate pressure of soil on enclosures (case of landslide pressure), and problems on bearing capacity of horizontal base of a die are considered. The problems of stability theory are formulated as linear programming tasks. It is shown that the given systems of equations are linear with respect to the unknowns and may be solved by the Simplex method. The results of soil stability problems calculation by Simplex method are compared with the results of calculations according to the most known classical schemes. It is shown that a great scatter of final results is observed in calculating the stability of slopes by classical methods, and in this case, the results obtained by the Simplex method are the most trustworthy ones. The situation with landslide pressure definition is especially complicated in this sense where classical methods give a scatter of landslide pressure values by several times. It is established that with increasing discretization of the computational domain, the results tend to exact solutions of the limit equilibrium theory, obtained, for example, by the method of characteristics. The latter point is illustrated using the example of the problem of a die pushing into a ground massif with a Hill scheme bulge.
The use of fuzzy sets to determine the parameters of genetic algorithms that provide approximately the same execution time on the CPU and GPU
Authors: Agibalov Oleg , Ventsov Nikolay
Published: December 2021

The problem under consideration consists in choosing the number of k individuals, so that the time for processing k individuals by the genetic algorithm (GA) on the CPU architecture is close to the time for processing l individuals on the GPU architecture by the genetic algorithm. The initial information is data arrays containing information about the processing time of a given number of individuals by the genetic algorithm on the available hardware architectures. Fuzzy numbers are determined based on these arrays?~? and?~?, describing the processing time of a given number of individuals, respectively, on the CPU and GPU architectures. The peculiarities of the subject area do not allow considering the well-known methods of comparison based on the equalities of the membership functions and the nearest clear sets as adequate. Based on the known formula “close to Y (around Y)” the way to compare fuzzy numbers?~? and?~? was developed in order to determine the degree of closeness of the processing time of k and l individuals, respectively, on the hardware architectures of the CPU and GPU.
Modeling and visualization of the forecast trajectory for the decision support system for controlling the movement of a river displacement vessel
Authors: Galeev R E , Soloviev A V , Fedosenko Y S
Published: December 2021

An approach to dynamic modeling of the predicted trajectory of movement of a displacement vessel and its continuous visualization on an electronic panel is considered, superimposed on the actual digital twin of the real scene of the environment along the course of the vessel. The hardware and software implementation of the developed approach as a decision support system for the navigator in the form of a standard option of the integrated control panel located in the wheelhouse provides an opportunity to objectively assess the safe distance to potential navigation obstacles within the ship’s course at the free distance of the vessel by means of combined visualization.

As part of the organizational and technical measures to ensure the safety of navigation, the proposed innovative approach to continuous joint visualization of the digital twin of the current scene of the surrounding sailing situation and the predicted trajectory of the vessel’s movement acquires significant importance in the operation of automatic vessels as an option for the supervisor to intervene in the operation of an integrated automatic control system in complex navigating conditions.
Orbital stability analysis of trajectories of highly nonlinear dynamic systems with feedback coupling
Authors: Annakulova G K
Published: December 2021

Orbital stability and qualitative study of the oscillations of a highly nonlinear dynamic system with feedback coupling are considered. For a highly nonlinear dynamic system with feedback coupling that satisfies Liénard’s theorem (on the existence and uniqueness of a periodic solution), a complete study of the phase pattern of the system is conducted. Applying the Poincaré criterion, the conditions for the existence of limit cycles and their Lyapunov stability are determined. The diagrams of phase trajectories are constructed numerically using the Mathcad 15 software package. Limit cycles are established, which are consistent with the limit cycles obtained by the Poincaré method. The behavior of trajectories outside the limit cycles is investigated. Recurrent homogeneous Pfaff equations are obtained, which determine the behavior of the systems “at infinity”. It was determined that the infinitely distant point of the horizontal axis is the only singular point for these equations. Linear approximations of recurrent homogeneous equations are obtained, which make it possible to determine the nature of the singular points. It was found that the trajectories then wind like a spiral on the limit cycles. Images of trajectories on the phase plane outside the limit cycles for the cases of degrees of nonlinearity under consideration are constructed.
Using multivalued logic for qualitative data analysis
Authors: Lyutikova L A
Published: December 2021

The paper considers a logical approach to data analysis to solve the classification problem. The studied data is a set of objects and their features. As a rule, this is scattered heterogeneous information and it is not enough for a reasonable application of probabilistic models. Therefore, logical algorithms are considered, which under certain conditions may be more adequate. For an expressive formal representation of the relationship between objects and their attributes, multivalued logic is used, and the number of values depends on a specific attribute. Therefore, a system of operations is proposed for variables with different domains of definition. As a result, a decisive function is built, which is a classifier of objects that are present in the studied data. The properties and capabilities of this function are analyzed. It is shown that the logical function, which is a conjunction in the space of rules connecting given objects with their characteristic features, uniquely characterizes the initial data, divides the subject area into classes, possesses modifiability properties, meets the requirements of completeness and consistency in a given area. The paper also proposes an algorithm for its implementation.
Mathematical modeling of the pollutant distribution process in the Gelendzhik Bay
Authors: Litvinov V N , Rudenko N B , Filina A A , Nikitina A V
Published: December 2021

Currently, the pollution problem of coastal sea waters in the resort areas of the Black Sea is becoming increasingly urgent. Thousands of chemicals, industrial and household waste enter the water basins every year, which significantly worsens the state of marine waters. Storm drains are saturated with pollutants at precipitation, washing out various chemical compounds, garbage and transporting them to the sea. In addition, a separate problem is poorly self-cleaning of the Gelendzhik Bay. A complete water change occurs in the period from 1 to 6 days. This paper covers the development, research and numerical implementation of a mathematical model of the pollution transport, including petroleum products, in the Gelendzhik Bay taking into account a number of important hydrodynamic and hydrophysical factors, methods of its numerical implementation, which allow predictive modeling of the pollution spread in shallow water systems in a limited time. A hydrobiological model of a coastal system characterized by significant depth differences has been developed. A three-dimensional mathematical model is designed to research the transformation of the phosphorus, nitrogen and silicon forms in the plankton dynamics problem. It takes into account the convective and diffusive transports, absorption and release of nutrients by phytoplankton, salinity, temperature, oxygen regime, etc. Using a spatial-three-dimensional hydrodynamics model, taking into account the physical properties of water environment of the coastal system, calculation results are used as input data for the development of scenarios for the dynamics of transport processes and the transformation of pollution biogenic elements in the water.