bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mathematical processing of the signal in the track circuit for determining the location of the rolling stock
Authors: Seroshtanov S S , Sokolov M M , Khodkevich A G 
Published: May 2021

Abstract
The article considers the issues of determining the location of rolling stock on the section of the railway track. Application of mathematical apparatus of conformal mappings is proposed and justified. Principle of conformal transformations of track circuit signal into the coordinate of place of superposition of the shunt is disclosed. Visualization of conformal transformations is presented using the example of a 420 Hz track circuit. The rules for determining the coordinate of the place of superposition of the shunt is well-phrased. Factors affecting the accuracy of determining the location of rolling stock on the section of the railway track have been determined.
The determination of distances between images of objects based on persistent spectra of eigenvalues of Laplace matrices
Authors: Chukanov S N 
Published: May 2021

Abstract
The work uses the method of filtering simplicial complexes, similar to the method used in the formation of persistent homology. The filtering process creates a number of nested simplicial complexes encoded with topological information. In papers [1-6] algorithms for the formation of persistent barcodes are used to compare images of objects. The use of persistent homology in relation to the methods of traditional algebraic topology provides additional information about the image of an object. To increase the diversity of information and the number of machine learning features, this work proposes algorithms for the formation of persistent spectra of eigenvalues of Laplace matrices for comparing images of objects. When comparing the shapes of objects, it is proposed to construct a modified Wasserstein distance based on the determination of the spectra of the eigenvalues of the Laplace matrix of the compared shapes.
Mathematical modeling and analysis of conditions for the robot’s uniformly accelerated motion along a straight rail track, taking into account the delay intervals
Authors: Lyubimov V V 
Published: May 2021

Abstract
The problem of the straight-line motion of a robot along a rectilinear rail track with the constant acceleration with delay intervals is considered. The aim of the paper is to determine and analyse the conditions describing the straight-line uniformly accelerated motion of the robot, taking into account the delay intervals. The law of speed change of the robot is simulated, using linear piecewise continuous functions of the time of motion. The necessary conditions for the uniformly accelerated motion of the robot in the acceleration and deceleration sections are formulated. Additionally, the criteria for uniformly variable acceleration and deceleration in the straight-line motion of the robot without delay intervals are recorded. It should be noted that the conditions and patterns presented in this paper have many practical applications. For example, they can be used in the development of traffic routes or in the operation of railway trains.
Solving logistics on the basis of fuzzy package
Authors: Muhamediyeva D K , Mirzaraxmedova A X 
Published: May 2021

Abstract
The article discusses an approach to solving a logistic problem based on fuzzy set theory. The classic fuzzy control module is developed at the node of the transport network, as well as when solving the problem of modeling the traffic control strategy in the network. An ambiguous rule base was developed for defining traffic control parameters at a transport network node, and rules were proposed for mapping a control parameter to a specific class and fuzzy rule base.
Modelling and presentation of cyber-physical systems on the morphological approach basis
Authors: Rakov D L 
Published: May 2021

Abstract
The article discussed cyber-physical systems are considered as a logical evolutionary stage in the development of system theory and system analysis. Cyber-Physical systems are a complex of interacting computational and physical components, with a constant exchange of information with the environment. The computational component can be easily changed and adapted to changing environmental conditions. At the same time, the re-construction of physical elements causes certain difficulties and already at the stage of conceptual design, they should be able to adapt to changes in the environment. Their use will allow you to achieve many advantages in the creation, management and operation of complex systems. These systems are highly adaptable in response to environmental changes, which leads to increased efficiency, are adaptable and transformative, and contribute to increased efficiency. The aim of the research was to find the position of cyber-physical systems in the general theory of systems. Morphological analysis was used for justification and selection, and it is proposed to use agglomerative clustering. The morphological representation made it possible to clearly determine the place of cyber-physical systems and to obtain a morphological set of possible variants. The creation of a classification morphological matrix will increase the accuracy of identification of these systems. For the first time, a morphological classification of cyber-physical systems as subsets of complex systems is given.
On generic complexity of the problem of searching of isomorphism for finite semigroups
Authors: Rybalov Alexander 
Published: May 2021

Abstract
This article is devoted to the investigation of generic complexity of the problem of searching of isomorphism for finite semigroups. That problem can be formulated as follows. For any pair of isomorphic finite semigroup Si and S2 with elements {1, 2,…, n}, represented by its multiplication tables, we need to find a bijection (permutation) of the set {1, 2,…, n}, which implements an isomorphism between S1 and S2. As for the classical isomorphism problem, any polynomial (even probabilistic) algorithms are unknown for the problem of searching of isomorphism for finite semigroups. We construct natural subproblems of this problem, for which there is no polynomial generic algorithm, provided that this problem is hard in the classical case. The study was carried out within the framework of the state contract of the Sobolev Institute of Mathematics (project no. 0314-2019-0004).
Formation of informative signs for predicting the disease of highly productive cows with non-communicable diseases
Authors: Safarova L 
Published: May 2021

Abstract
In this article, fuzzy set membership functions have been developed based on the main factors (clinical, morphochemical, rumen contents) to predict the following non-communicable diseases such as ketosis, osteodystrophy, secondary osteodystrophy and hypomicroelementosis in high-yielding cows. The results of the study show the high efficiency of the proposed decision-making algorithm for forecasting, classifying and measuring poorly formalized processes, that are described by fuzzy models. The available knowledge about the existing experimental data makes it possible to increase the adequacy of the fuzzy expert system.
New approaches to constructing quadrature formulas for functions with large gradients
Authors: Zadorin A I 
Published: May 2021

Abstract
The problem of numerical integration of functions with large gradients in the boundary layer is studied. The use of the Newton-Cotes formulas on a uniform grid to integrate such functions can lead to significant errors. The article investigates approaches to the construction of quadrature formulas, the error of which does not increase due to large gradients of the function in the boundary layer. The following approaches are considered: the construction of quadrature formulas that are exact on the singular component responsible for the growth of the function in the boundary layer, the application of the Newton-Cotes formulas on the Shishkin and Bakhvalov meshes, minimization the error of the quadrature formula due to the construction of nodes. The investigated approaches are new, partially reflected in the publications. The results of computational experiments are presented.
Development and application of the geometry constructions language to building computer geometric models
Authors: Boykov A A 
Published: May 2021

Abstract
Geometric models for industrial purposes are created in CAD systems making use of geometric constructions commands. At the same time, the so-called constructive or synthetic (as opposed to analytical) method to create a geometric model is implemented. The set of tools of any CAD system is limited, so accomplishing a specific task will require repeating a series of geometric constructions of the same type to form the desired shape. In this paper, a specific GC language (Geometry Constructions Language) is proposed to introduce an automated process of geometric modeling. To do this, theoretical issues of constructive geometry are analyzed, the main objects and syntax of the GC language are identified. The paper provides an example of building a model of a temple dome using GC language translator. It is noted that the GC language allows geometric modeling of regular curves (including trajectory of objects) and surfaces and applying new geometric correspondences and transformations. At the same time, geometric models in CAD systems are created faster since you don’t have to repeat manually the same type of construction or develop new equations and formulas for calculations.
Predictive geometric models for some hygienic properties of multi-component fabrics
Authors: Chizhik M A , Yurkov V Yu , Dolgova E Yu 
Published: May 2021

Abstract
This paper is devoted to the geometric and computer simulation of hygienic properties of fabrics which are considered as multi-parameter and multi-component systems. We consider predictive models of fabric hygroscopicity and air permeability. There is a problem of building co-ordinate geometric models on condition that the set of experimental data is limited. We solve the problem for static multi-component systems. All models are considered as monoidal surfaces in the space of input and output parameters. The paper proposes an algorithm of building linear and quadratic models of fabric properties. Results of the investigations allow us to substantiate producer’s choice of fabric construction and composition for manufacturing the clothes of special purpose. The method suggested in the paper is one of geometric modulus of the software HYPER-DESCENT which has been developed formerly. Our geometric models together with software HYPER-DESCENT may be applied for simulation and prediction the properties of multi-parametrical systems or technological processes of light industry.
Graphic modelling of the gear broaching process
Authors: Kondrashov A G , Safarov D T 
Published: May 2021

Abstract
The gear broaching method, in contrast to the hobbing methods with hob cutters, belongs to the shaping copying methods. The result of the gear broaching is a gear profile that is geometrically different from the theoretical design profile of the bevel gears. The possibility of graphical modeling of the results of the gear broaching process is currently absent, which makes it impossible to measure the geometric parameters of the rims of the gear wheels after their processing. The article proposes a method for graphical modeling of the process of gear broaching of bevel gears, including the construction of actual profiles of the broaching teeth, the adjustment scheme of the gear broaching machine, obtaining a family of trajectories of movement of each broaching tooth, aligning and stretching the profiles along the trajectories to obtain shaping elements. Subtraction of the shaping elements from the gear blank model produces a geometrically accurate 3D model of the bevel gear, which is the result of the interaction of each broach tooth and the blank.
Principles of solid modelling in point calculus
Authors: Konopatskiy E V , Bezditnyi A A , Lagunova M V , Naidysh A V 
Published: May 2021

Abstract
The article describes the principles of solid modelling in point calculus, including the definition of geometric bodies in the form of an organized set of points in space. At the same time, the choice of point calculus as a mathematical apparatus for effective modelling of geometric bodies in 3-dimensional space is substantiated, expanding the instrumental capabilities of computer graphics. By means of generalization, it has been established that the dimension of the space in which the geometric body is defined is equal to the number of current parameters. On the basis of this, a new definition of a geometric body is proposed as a geometric set of points, in which the number of its determining parameters is equal to the dimension of space. Examples of the definition of a tetrahedron body and a triangular prism body in point calculus, obtained considering the proposed definition of the term “geometric body”, are given. The obtained point equations are completely invariant with respect to the choice of the coordinate system and depend only on the coordinates of the points that define the vertices of the modelled bodies. Thus, the obtained point equations determine the entire set of bodies of tetrahedrons, bodies of triangular prisms, bodies of elliptical cylinders and cones in 3-dimensional space. The prospect of further research is the definition in point calculus of geometric bodies of curvilinear and irregular shapes, considering their relative position in space, as well as more complex composite geometric bodies in 3-dimensional space.
Simulation of a cylindrical-conical gear train on parallel axes with an adjustable side clearance
Authors: Krukov V A , Nam T V , Plyasov A V 
Published: May 2021

Abstract
The geometrical synthesis of a cylindrical-conical transmission on parallel axes with external gearing is considered on the basis of the blocking contour method, which makes it possible to determine solutions for the right and left ends of the wheel. The use of the calcula-tion for cylindrical-conical wheels is described. We used our own algorithm for constructing the blocking contour and engagement in the Math CAD program, and a 3D model of the trans-mission in the KISSsoft program. For a better example, the contour and engagement in the 3D model are given.
Supercapacitors application possibilities for lifting equipment induction electric drives
Authors: Lysenko O A , Simakov A V 
Published: May 2021

Abstract
In the article, the supercapacitors (ionistors) application for lifting equipment induction electric drives is considered. Electric lifting equipment is widely used in industry, construction, municipal services. The lifting equipment efficiency is insufficient, therefore the research topic is relevant. At the moment, an induction electric motor with a frequency converter with a DC link is used to regulate the mode of lifting and lowering loads. To smooth out the ripple and use the braking energy of the moving masses when lowering the load, it is proposed to use a supercapacitor as a DC bus storage. A supercapacitor has three to four degrees more capacity than an electrolytic capacitor and can store more electricity. The paper provides simulation modeling of the electric drive of the lifting equipment. Stern’s equation is used as a supercapacitor mathematical model. According to the simulation results, the power consumption of an electric drive with a supercapacitor is 41.02% less than that of an electric drive with an electrolytic capacitor.
The three-level inverter topologies analysis for application by electric centrifugal pump units
Authors: Lysenko O A , Simakov A V 
Published: May 2021

Abstract
In the article, the schemes for providing AC power with frequency conversion for the induction submersible electric drive of oil production units are analyzed. The electric submersible drive is widely used and has stringent efficiency requirements, so this research is relevant. The centrifugal pump units are composed of a low-voltage power source, a frequency converter, a step-up transformer, a cable line, an electric drive and a centrifugal pump. This article discusses options for replacing the step-up transformer and two-level voltage / frequency converter with a three-level flying capacitor converter (FCC) or a three-level clamping diode converter (NPC). The expected states of the power high voltage IGBT modules are described. The waveforms of the inverter output voltage and the submersible induction motor stator voltage in different circuits are shown. A voltage levels analysis for each module is done, the electric drive starting time change is estimated, the total harmonic distortions (THD) are calculated, and a 1.1% THD reduction by applying the NPC circuit is shown. The harmonic current spectrum for each circuit is presented.
Determination of conditions for optimal control of a permanent magnet synchronous motor of a single-stage reciprocating compressor for a proposed law of motion for ensuring the maximum efficiency
Authors: Tatevosyan A A 
Published: May 2021

Abstract
Attention is paid to issues of reliability and economy while ensuring high performance of energy conversion processes occurring in various subsystems when a linear magneto-electric drive (LMED) is designed, which includes a permanent magnets synchronous motor with permanent magnets (PMSM) and a compressor stage. Reducing the number of elements included in the LMED, for example, transmission and conversion mechanisms is one of the directions that increase the reliability of the LMED. However, in this case, non-linear suction-discharge processes occurring in the compressor stage have a significant effect on the operation of the electromechanical converter. In this regard, the task of improving the energy efficiency of LMED can be solved in various ways. The article describes the LMED control conditions of a low-speed single-stage piston compressor, obtained from the solution of the problem of optimizing the design of the magnetic system PMSM, at which maximum efficiency is achieved. The relationship of the generalized parameters of the drive with the design features of the PMSM is established.
Effect of the noise component of the aperture uncertainty on the dynamic range of the sample and hold circuit
Authors: Zhenatov B D 
Published: May 2021

Abstract
In this article, the influence of the noise component of the aperture uncertainty on the dynamic range of the sample-and-hold circuit (S/H circuit) is considered. For this purpose, a mathematical model of the S/H circuit is constructed, which is presented in the form of an ideal sampler, at the input of which a functional block is placed that simulates distortions of the sampled oscillation in the real S/H circuit. An analytical expression is obtained to show that the noise component of the aperture uncertainty generates frequency distortions of the input signal and additional noise, the properties of which are determined by the characteristics of the aperture uncertainty and the sampled oscillation.
Tensile modeling of titanium-aluminum composite with a wave profile of a welded joint and local melts
Authors: Gurevich L M , Danenko V F , Pronichev D V , Pisarev S P 
Published: May 2021

Abstract
Finite element simulation of tensile deformation of titanium-aluminum composite D20 – AD1 – VT6 was carried out. The joint boundary had a wave profile and local melts. 3D modeling of deformation of the composite D20 – AD1 – VT6 with a wave profile of the welded joint was carried out using the SIMULIA / Abaqus software. The relative thickness of the AD1 interlayer and the area of the melt were varied during the simulation. To determine for metal hardening during plastic deformation and the failure deformations for aluminum and aluminum alloy both Johnson-Cook deformation and fracture models was used. The influence of the size of the local melting zone and thickness of the soft interlayer on the distribution of stresses and strains in the composite is shown. The wave profile of the boundaries junction leads initially to localization of plastic deformation in the aluminum interlayer in the zone of free surfaces of the sample near the interface with the titanium alloy. A change in the length of vortices with areas of local melting near the tops of the wave profile from 0.3 to 0.8 mm had little effect on the profile of the curves “equivalent stress-absolute elongation of the sample”.
Using the finite element method and dimension analysis in modelling laser shock processing of titanium alloys with shape memory
Authors: Sakhvadze G Zh 
Published: May 2021

Abstract
The technology of laser shock processing of titanium alloys with the shape memory effect is simulated using the finite element method and dimensional analysis. In total, 16 independent dimensionless parameters characterizing the mechanical behavior of shape-memory NiTi alloys are analyzed. The dependences of the influence of the dimensionless duration of the laser pulse and the dimensionless peak pressure in the shock wave on the dimensionless depth of the plastic zone are obtained.
Comparison of titanium nitride and high-entropy coatings on parts of industrial plants
Authors: Yurov V M , Eremin E N , Guchenko S A 
Published: May 2021

Abstract
The task of the work is to establish a relationship between the main parameters of high-entropy CuZrTiNiCr coatings and their mechanical properties on parts of industrial enterprises with classic titanium nitride coatings. The technique is based on the use of mechanical alloying methods for the synthesis of high-entropy alloys and the production of magnetron targets from them. The application of titanium nitride coatings and high-entropy CuZrTiNiCr coatings on the parts was carried out on an NNV-6.6I1 installation. Establishment that high-entropy CuZrTiNiCr coatings have a density of 5.72 g/cm3, and the density of titanium nitride coatings is 5.44. The microhardness of high-entropy coatings is 14.1 GPa, while for titanium nitride coatings it varies over a wide range 20.2 GPa. The friction coefficient of titanium nitride coatings changes 0.4-0.5, which is 10 times higher than that of the high-entropy CuZrTiNiCr coating-0.04. This antifriction property of the high-entropy coating on the parts of industrial enterprises leads to greater wear resistance and a longer service life, in comparison with classical titanium nitride coatings. Titanium nitride coatings on industrial parts were found to be 10 times less effective than high-entropy CuZrTiNiCr coatings. This is due to the wear resistance of these coatings, which is due to the very low coefficient of friction and low surface energy.
Cell constant analytical study of electrochemical flow cell with interdigitated microelectrodes
Authors: Kozlov A G , Fadina E A 
Published: May 2021

Abstract
This paper presents the results of investigating the influence of design parameters of an electrochemical flow cell based on film interdigitated microelectrodes on its cell constant. This investigation is performed by the analytical method. To determine the cell constant the linear resistance between the adjacent fingers of the interdigitated microelectrodes is used. In its turn this resistance is found from the potential distribution in the unit subdomain of the interdigitated microelectrode system of the cell with the limited height. The dependencies of the cell constant on the cell height and the design parameters of the interdigitated microelectrode system (the spacing between fingers and the finger width) are determined. The cell height at which the change of the design parameters of the interdigitated microelectrode system has the least effect on the cell constant is found.