bluuebunny/crossref_metadata_2025 huggingface dataset:
Diffraction from excitonic diffraction grating
Authors: Kapitonov Yu V , Shapochkin P Yu , Petrov Yu V , Lovtcius V A , Eliseev S A , Efimov Yu P
Published: November 2019

In this paper we consider two methods for the theoretical modelling of the reflection and diffraction spectra from an excitonic diffraction grating made from a quantum well with spatial modulation of the exciton resonance. The modelling was performed in the single-scattering approximation, and by the step-by-step approximations of the exact solution of Maxwell’s equations. The expressions are obtained for the modulation of the inhomogeneous broadening of the exciton resonance. Theoretical results are compared with the experimental data for the quantum well grown on an ion irradiated substrate, and for a quantum well irradiated with ions after growth.
Calculation of diffractive optical elements for the formation of thin light sheet
Authors: Khorin P A
Published: November 2019

In the work, the calculation and study of diffractive optical elements (DOE) for the formation of a diffraction-free beam in the form of a thin light sheet, which can be used in planar microscopy, were performed. The calculation of phase DOEs is made on the basis of an iterative algorithm, taking into account the quantization of the phase function.
The resolution of optical image edge detection based on Brewster effect
Authors: Kolesnikova M D , Lyubarskaya A V , Nesterenko D V , Soifer V A
Published: November 2019

In the present work, we study the influence of the Brewster effect on the resolution of optical system for optical edge detection. The estimation of resolution for initial and transformed images of optical objects is performed both theoretically and experimentally. Our research demonstrates that the image edge detection based on the transformation by the Brewster effect improves the resolution of the optical system approximately by the factor of 1.6.
Conditions improving of laser heating for forming of materials with a ferritic-martensitic structure
Authors: Murzin S P , Liedl G , Bielak R , Melnikov A A
Published: November 2019

High-strength dual phase ferritic-martensitic steels with a controlled amount of martensite have the most favorable combination of durability and plasticity compared to other low-alloy steels. The possibility of conditions improving of laser heating for forming sheet materials with a ferritic-martensitic structure has been determined. It is shown that the redistribution of the power density of the heat source allows this process to be performed without a significant local decrease in the profile thickness. A diffusion-cooled and high-frequency excited CO2 laser ROFIN DC 010 with a maximum output power of 1000 W was used as the laser source. To redistribute the laser power density, a diffractive optical element (DOE) was used. The region of plastic deformation is characterized by a local decrease the thickness profile, while microcracks and a discontinuity of the metal weren’t observed.
Fiber-optical system for transmitting heterodyne signals in active phased antenna arrays of radar stations
Authors: Moroz A V , Davydov V V
Published: November 2019

For transmitting reference and heterodyne signals of active phased array antenna is developed a new design of a fiber-optic communication system. In article are considered of transmission features of reference and heterodyne signals in is developed by us of new design of a fiber-optic communication system. The data of experimental investigation are presented.
The expediency of fiber-optical communication line used in different schemes of receiver tract of the radio-monitoring complex
Authors: Podstrigaev A S , Lukiyanov A S , Smolyakov A V , Shishkov A N , Davydov V V , Nikitina M I
Published: November 2019

In the article the all variants of broadband and narrowband receiver tract design schemes for microwave signal transmission in radio monitoring complexes are considered. The characteristics of receiver tract with use of fiber-optic communication line or microwave cable in its various parts are presented. The features, advantages and disadvantages of fiber-optic communication lines using are marked. The comparison of the investigation characteristics of receiving tract parts with foreign analogues are performed. The results of experimental research and theoretical calculations are presented.
Physical foundation of optical smart antenna based on metamaterial and lithium niobate
Authors: Vytovtov K , Barabanova E , Igumnov M
Published: November 2019

In this work we present the main physical foundations of optical antenna array. This antenna array is based on the mirror system and lens system. To provide the necessary phase shift we propose two kind of structures: based on litium neobate and on ferrite-garnet. The main analytical expressions describing system behaviour are found for the first time. The results of calculation of the lens system parameters in the program ZEMAX are presented also.
The propagation of pulses of a special shape in an inhomogeneous anisotropic medium with dispersion and torsion of the optical axis
Authors: Moiseeva N , Moiseev A
Published: November 2019

An oblique incidence of polarized light pulses with different envelope shapes is considered: triangular, Gaussian, rectangular and in the form of giant laser pulses onto a flat inhomogeneous anisotropic layer with torsion of the optical axis and optical dispersion. The wavelength of an optical pulse carrier is close to the resonance wavelength of an inhomogeneous anisotropic layer. The problem of the propagation of s- and p-polarization waves through a layer, the reflection of impulses of cross-polarized components, the dependence of modulation coefficients during medium torsion and frequency detuning is considered.
Multivariate analysis of tissues Raman spectra using regression methods
Authors: Lykina A A , Artemyev D N , Kukushkin V I , Bratchenko I A , Avraamova S T , Aleksandrov N S
Published: November 2019

This work is devoted to the study of intact and tumor kidney tissues spectral properties. 532 nm, 785 nm, and 1064 nm lasers were used to stimulate Raman spectra and autofluorescence. Visually and morphologically unchanged tissues of human kidneys as well as tumor tissue were examined. Raman spectra have specific spectral markers for each tested subject. The analysis of the spectral characteristics was carried out with using projection on latent structures method to highlight the spectral features between the tissues.
Forming of three-dimensional optical fields consistent with the superposition of scalar spherical harmonics
Authors: Monin E O
Published: November 2019

Spherical functions are the angular part of the family of orthogonal solutions of the Laplace equation written in spherical coordinates. They are widely used to study physical phenomena in spatial domains bounded by spherical surfaces and in solving physical problems with spherical symmetry. In this paper, the superposition equation of spherical harmonics satisfying the Helmholtz equation was obtained. Modelling and visualization of three-dimensional fields, coordinated with separate spherical harmonics and their superpositions, was carried out.
Features of the transmission of microwave signals at offshore facilities
Authors: Pchelkin G A , Fadeenko V B , Davydov V V
Published: November 2019

In the article the capabilities of microwave signals transmission by fiber-optic communication lines on marine objects is considered. The features of constructing a scheme for transmitting a microwave signal from a passive antenna over a fiber-optic communication line are established. The technical solutions for optimizing the design of a fiber-optic communication line are proposed. The results of experimental investigations of fiber-optic communication lines parameters are presented.
A complex study of the structure “carbon nanotubes - silicon substrate” photoconductivity mechanism
Authors: Tripathi N , Pavelyev V S , Mezhenin A V , Sovetkina M A , Rymzhina A R
Published: November 2019

The types of optical radiation photodetectors have been considered according to the principle of action. A theoretical and experimental study of the electron generation mechanism in the structure “carbon nanotubes – silicon substrate” under the influence of the far infrared range radiation has been carried out. It has been established that such structures are thermal radiation receivers of the bolometric type.
Features of the construction of the registration scheme of optical images in an autonomous quantum magnetic field sensor
Authors: Logunov S E , Davydov R V , Vysotsky M G , Dudkin V I , Yu Rud’ V
Published: November 2019

The article describes the design of an autonomous quantum sensor for detecting variations of the magnetic field. The features of the regulation of the diffraction pattern of laser radiation using a ferrofluid cell placed in a uniform constant magnetic field are established. The optimal parameters for the design of the ferrofluid cell, magnetic fluid and laser radiation were determined. The experimental results of the study of the variation of the magnetic field from moving marine objects are presented.
Development of a software package for modeling and analysis of light diffraction on periodic structures of nanophotonics by the rigorous coupled-wave analysis
Authors: Komarov I S , Bezus E A
Published: November 2019

We discuss the development of a software package, which enables simulating and analyzing the diffraction of a plane electromagnetic wave on a multilayer diffraction grating with. The main functional requirements to the system are formulated. The architectural solution of the implemented software including the main functional and logical layers of the system with the specified methods of their interaction is described. The method allowing one to model light diffraction on multilayer diffraction structures comprising homogeneous layers and diffraction gratings with one-dimensional periodicity is implemented. A polarizing reflector consisting of a diffraction grating on a Bragg grating (a one-dimensional photonic crystal) consisting of a small number of layers is designed and investigated. The optimal parameters of the structure are found for a given reflectance criterion. The parameter ranges satisfying the chosen criterion are investigated. The influence of changes in the geometric parameters of the structure on the reflector performance is discussed. The designed software package is promising for the design of grating-based nanophotonic filters and sensors.
In vivo Raman and autofluorescence study of the pigmented skin neoplasms
Authors: Khristoforova Y , Bratchenko I , Bratchenko L , Konovalov S , Andreeva A , Moryatov A , Kassirov D , Orlov A , Kozlov S , Zakharov V P
Published: November 2019

This paper studies classification of the pigmented skin neoplasms on the basis of the spectral Raman and autofluorescence features. The spectra registration was performed by means of the portable spectroscopic system with 785 nm laser radiation. The analysis of the spectral data was carried out using a projection on the latent structure with linear discriminant analysis. Using regression analysis the correlations between Raman and autofluorescence data were estimated. The variable importance in projection analysis allows one to find out important spectral information to differ spectra of the different neoplasm types. The use of combination of the Raman/autofluorescence data and projection method made it possible to classify pigmented skin neoplasms with 81% accuracy.
Analysis of the resonance characteristics of surface plasmon polariton modes at air-metal interfaces in the ultraviolet, visible and infrared regions
Authors: Nesterenko D V , Pavelkin R A , Hayashi S , Soifer V A
Published: November 2019

Excitation of surface plasmon polariton (SPP) modes results in the appearance of resonance line shapes observed in the attenuated total reflection spectra of layered structures in the Otto or Kretschman configurations. The sensitivity of the resonance characteristics of the propagating modes to changes in optical characteristics of the environment is widely used in sensor devices to determine qualitative and quantitative changes in the environment, as well as low concentrations of substances adsorbed on the surface. In the present work, we analyze the resonance characteristics of SPP modes based on the optical properties of plasmonic materials. Interfaces of metal-dielectric structures support the propagation of SPP modes. Estimation of the dispersion dependences of the propagation constant of the SPP mode, sensitivity to changes in external conditions, enhancement of the near field on the surface is carried out within the electromagnetic theory based on approximations of asymmetric shapes of spectral resonance lines of SPP by Fano formulas in the ultraviolet, visible, and infrared regions.
The dependence of the image edge detection directivity by Brewster effect on the gradient of inhomogeneities of objects
Authors: Nesterenko D V , Lyubarskaya A V , Kolesnikova M D , Soifer V A
Published: November 2019

Optical image edge detection for amplitude and phase objects can be performed using Brewster effect. We demonstrate experimentally that the direction of the amplitude and phase gradients in the objects affects the image transformation directivity. In the theoretical study, we consider transfer function for in-plane and out-of-plane rays. The results of this work can be used for design and optimization of optical systems for image and information processing.
Polarization-dependent orbital angular momentum flipping in fibers with acousto-optic interaction
Authors: Yavorsky M A , Vikulin D V , Barshak E V , Lapin B P , Alexeyev C N
Published: November 2019

In this paper we consider the evolution of linearly polarized optical vortices in circular optical fibers with a propagating fundamental flexural acoustic wave. A new polarization-dependent mode conversion is found out, in which the sign of the topological charge (and orbital angular momentum) of the outgoing vortex beam is governed by the direction of the incident linear polarization. This effect can be used for implementing polarization-controlled orbital angular momentum flipping. This paves the way to implementation of the all-fibre stable controlled-NOT gate, in which the linear polarization carries the control qubit and the topological charge carries the target. Such a gate is able to produce optical beams with entanglement between polarization and orbital degrees of freedom in regime of linear optics. Yet, such orbital angular momentum controlling should be useful in micromechanics, classical and quantum information encoding, and classical simulation of quantum algorithms.
Development of virtual roughness comparators
Authors: Abulkhanov S R , Poletaev S D
Published: November 2019

The surface roughness is inspected visually or by the contact profiling method. In both cases, actual roughness comparators with the preset roughness parameters (Ra) are used. The reference surface is created by various technological impacts. Technological processes are influenced by random factors; therefore, the reference surface has the deviations of the Ra parameter from the declared value. We suggest to control the roughness based on its image. In this case, the data available is not enough to determine the standard roughness parameters. We introduce the rough surface parameter ζ, which uses the standard parameters Ra and Rz.

We studied five images of roughness comparators made on glass using a New View 7300 white light interferometer. We determined the nominal value of the roughness parameter ζ for each roughness comparator and for each line of the rough surface images of 5 comparators. We considered the images of the reference surfaces as an indirect measurement of microrelief heights. We generated a reference rough surface based on the image of the actual surface of the roughness comparator. We used Spearman correlation coefficient to identify the most characteristic fragments of the reference rough surface. The virtual rough surface comparator created by us allows to increase the objectivity of visual control of rough surfaces and measure the similarity of the target and the reference rough surfaces.
Optical inspection device for the inner surface of pipe ends
Authors: Abulkhanov S R , Ivliev N A
Published: November 2019

The inner surface of the holes in the ends of tubing pipes used in oil production is most prone to deterioration. The mechanical loads combined with corrosion lead to the formation of pits on the surface of the holes. A tubing burst leads to significant financial, technological and environmental losses. The existing methods of non-destructive inspection do not allow to measure the depth of a corrosion pit (cavity) on the surface of the pipe end hole. We propose the construction of the device for monitoring the pipe inner surface closely adjacent to its end. The device uses the optical principle of monitoring the presence and the depth of corrosion pits on the surface of the tubing pipe end hole. The device uses structured lighting of the ring of the hole surface. Judging by the out-of-roundness of the light-shadow border, we evaluated the depth of the defects on the hole surface. The device was tested and calibrated on a special stand, where the depth of the cavity was changed with a step of 30 microns. The reflected light flow from the target surface was recorded by a video camera. Tests of the device showed its resistance to the disturbances in the form of stray lighting, electromagnetic interference, vibrations and dirt in the room (no special operating conditions are required). The length of the corrosion pit does not affect the sensitivity of the device. If the material of the controlled tubing changes, the device shall be calibrated. For a 4 mm long defect, the depth of the corrosion pit up to 1.5 mm can be detected. Preliminary calibration of the device allows to reduce the measurement errors caused by the technological and operational reasons. The developed device is able to detect the presence of a corrosion pit on the hole surface. The accuracy of measuring the depth of the defect on the pipe surface is not less than 150 microns, which is acceptable for oil pipe repair plants. The device can be operated manually and can be built into an automated control system. The monitoring results can be documented. The developed device can be used in other areas: inspection of holes made in reinforced concrete structures, inspection of surface of the holes of chemical production pipes, GTE fuel system, etc.
Laser technologies in the formation of harmonic lenses microreliefs
Authors: Danilov V A
Published: November 2019

Briefly describes the technology of forming high microreliefs in the context of the scientific path of a senior researcher at the Institute of Image Processing Systems of the Russian Academy of Sciences Candidate of Technical Sciences Oleg Yuryevich Moiseyev - a unique specialist in the technology of diffraction computer optics, recording optical micro- and nanorelief.
Reducing dimension of parametric space based on the approximation of components for interpolation of multidimensional signals
Authors: Gashnikov M V
Published: November 2019

In this paper, we address the problem of parametric space dimension reduction in the interpolation of multidimensional signals task. We develop adaptive parameterized interpolation algorithms for multidimensional signals. We perform a dimension reduction of the parameter space to reduce the complexity of optimizing such algorithms. The dependences of the samples inside the signal sections and between the signal sections are taken into account in various ways to reduce the dimension. We consider the dependencies between the signal sections through the approximation algorithm for the sections. We take into account the sample dependencies inside sections due to an adaptive parameterized interpolation algorithm. As a result, we solve the optimization problem of an adaptive interpolator in the parameter space of lower dimension for each signal section separately. To study the effectiveness of adaptive interpolators, we perform computational experiments using real-world multidimensional signals. Experimental results showed that the proposed interpolator improves the efficiency of the compression method up to 10% compared with the prototype algorithm.
Spatial interpolation methods for spectral-spatial remote sensing image super-resolution algorithm based on gradient descent approach
Authors: Belov A M , Denisova A Y
Published: November 2019

The paper presents an investigation of the influence of spatial interpolation methods on the quality of the image obtained as a result of the spectral-spatial remote sensing image super-resolution reconstruction based on the gradient descent approach. As an example of the super-resolution method, we applied our earlier developed super-resolution image reconstruction algorithm. The algorithm provides the minimization of error of the observation model that connects the input low-resolution images with the target high-resolution image. The iterations of the gradient descent method are performed in the high-resolution spectral and spatial coordinates grid. For this reason, the spatial interpolation operator is added in the observation model. It is evident that spatial interpolation affects both the quality of the reconstructed image and the algorithm convergence rate. The objective of our research was to define the most appropriate spatial interpolation method. The paper presents the results of the spectral-spatial super-resolution image reconstruction using the following spatial interpolation methods: bilinear, bicubic, sinc, and nearest neighbour interpolation. We compare these implementations in terms of such image quality indicators as the root mean square error of the estimated high-resolution image, the algorithm convergence rate, and the presence of textural and colour artefacts as well.
Approximation of the road segments travel time using Levy distributions in the reliable shortest path problem
Authors: Agafonov A A , Myasnikov V V , Maksimov A I
Published: November 2019

The current trend towards an increase in the number of vehicles, especially in large cities, as well as the unavailability of the existing road infrastructure to distribute modern traffic flows leads to a higher congestion level in transportation networks. This problem emphasized the relevance of navigation problems. Despite the popularity of these problems, many existing commercial systems consider only deterministic networks, not taking into account the time-dependent and stochastic properties of traffic flows. In this paper, we consider the reliable shortest path problem in a time-dependent stochastic transportation network. The considered criterion is maximizing the probability of arriving at the destination point on time. We consider the base algorithm for the stochastic on-time arrival problem, which has a computationally complex convolution operation for calculating the arrival probability. We propose to use parametrically defined Levy stable probability distributions to describe the travel time of road segments. We show, that the use of stable distributions allows us to replace the convolution operation with the distribution value, and significantly reduces the execution time of the algorithm. Experimental analysis has shown that the use of stable distributions allows approximating the exact value of the arrival probability at a destination with a low approximation error.
Technique to model the movement of the scene using image sequence
Authors: Tashlinskii A G , Kovalenko R O , Smirnov P V , Suetin M N
Published: November 2019

The paper proposes a technique to model the movement of a scene based on backward stochastic gradient pixel-by-pixel estimation of the deformation field. Calculation of the moving object’s area is considered as the task of testing the hypothesis that the image grid nodes belong to the area of motion. The paper presents the estimated two kinds of errors: false positive and false negative. The obtained results are compared with the results of the MVFAST algorithm. The increase in the signal-to-noise ratio of the image of a moving object is achieved by combining the frames of the video sequence under study. To combine conjugate points, high-speed recurrent algorithms are used that do not require a priori information. The paper presents an example of estimation of object’s trajectory parameters using the technique. The interframe geometric deformations of the video sequence are used as intermediate parameters of the trajectory.
Segmentation of 3D FIB-SEM data with pore-back effect
Authors: Reimers I A , Safonov I V , Yakimchuk I V
Published: November 2019

Digital rock physics is used for the investigation of oil and gas reservoirs. It involves various mathematical simulations on a digital representation of a rock sample, which is usually obtained with imaging techniques. Focused ion beam scanning electron microscopy (FIB-SEM) tomography provides high-resolution images of sequential layers of a sample, and segmentation of these images is a key stage in the construction of 3D digital rock. Conventional segmentation methods are not applicable for FIB-SEM images due to specific artifacts such as the pore-back effect. We propose a new segmentation algorithm that relies on the marker-controlled watershed, variance filter and morphological operations. The results are validated with the use of manually labelled ground truth data. Furthermore, we develop a new metric for evaluation of segmentation quality. This metric is based on analysis of segmented regions and, in the case of porous media, provides more reliable evaluation than pixel-wise measures.
Shadow detection on color images
Authors: Kurbatova E E , Lyalina V A
Published: November 2019

The shadow areas cause significant problems in objects recognition and classification applications. The shadows have uniform properties in some colour spaces. Thus, the shadow detection can be effectively done by applying the threshold processing. This paper proposes a simple method to detect shadows in images using the combination of two components from different colour spaces. The B component of LAB colour space is used to detect homogenous areas using contour segmentation algorithm. The method uses the V component of HSV colour space to decide whether the obtained areas (the result from the segmentation stage) are shadowed or not. This stage is done using the mean value of the V component for these areas and subsequent thresholding based on Otsu’s method. The experimental results show that the proposed approach can get accurate detection results like the state-of-art-methods, while it is more stable for the difference of characteristics of initial images.
Natural and revitalized grassy ecosystems as biodiversity refuges: on the abilities of remote sensing for their detection and study
Authors: Bavrina A Y , Denisova A Y , Kavelenova L M , Korchikov E S , Kuzovenko O A , Makarova Y V , Prokhorova N V , Terentyeva D A , Fedoseev V A
Published: November 2019

The natural and revitalized on the place of former fields grassy ecosystems can be the refuges (places of conservation in natural conditions) for many types of rare plant species. Such ecosystems are of great interest for the environment exploration and management activities planning over many countries including EU and USA. Samara region territory demonstrates the residual nature of grassy ecosystems as a result of intensive agricultural exploration of virgin grasslands, located here at the past. Consolidative usage of remote sensing data and ground-based surveys is the common practice nowadays. This paper describes the possibilities of high-nature value grasslands classification in Samara Region using intra-annual time series of multispectral remote sensing data of medium spatial resolution with the use of spotted ground-based surveys. Investigations engage the training set generation for the large natural vegetation communities with ground-based survey optimization and include the classification results for two vast grassland objects with protected status.
A new watermarking method for vector map data: a study on information capacity of the carrier image
Authors: Vybornova Y D , Sergeyev V V
Published: November 2019

The paper presents a study of the watermarking method for vector map data based on the cyclic shift of the vertex list of polygonal objects. We propose a method modification to provide an accurate authentication procedure, as well as to enhance the method robustness against the map contents alteration. The main idea of the improved method is to use a noise-like image as a secondary container for a watermark represented in the form of a bit vector. An algorithm for the construction of a carrier image on the basis of the watermark sequence, as well as an algorithm for extraction of such a sequence, are given. An experimental study on the information capacity of the carrier image and its robustness against distortions simulating the embedding into real cartographic data, such as quantization and noise addition, has been carried out.
Measuring parameters of canvas texture from images of paintings obtained in raking light
Authors: Murashov D M , Berezin A V , Ivanova E Yu
Published: November 2019

In this work, the problem of threads counting in images of canvases of paintings is considered. Counting of threads is necessary for measuring canvas density and a number of other parameters used by art historians for dating the artworks. We propose to use raking light in the image acquisition process in order to emphasize canvas texture. We modify and adapt known techniques developed for inspecting fabrics in the textile industry. Three threads counting algorithms based on filtering in the Fourier domain and thresholding techniques are proposed and tested. These algorithms for measuring the canvas density from images taken in raking light are efficient in cases when lead white has been used to create the painting, and the analysis of canvas images acquired in X-rays and transmitted light is ineffective. The results of the experiment show that the accuracy of the proposed threads counting algorithms is comparable to the accuracy of known techniques.
Elimination of information redundancy of hyperspectral images using the “well-adapted” basis method
Authors: Vasin D Yu , Gromov V P , Pakhomov P A
Published: November 2019

The paper considers some issues of eliminating information redundancy of hyperspectral images (HSI). The characteristic properties of the HSI are listed, a brief description of the existing HSI compression methods is given. The possibility of using local, homogeneous “well-adapted” basis functions (LHWABF) to eliminate information redundancy and adaptive compression of the HSI is considered. An algorithm for constructing a LHWABF system for the HSI based on the Chebyshev approximation is proposed. The results of computational experiments, including the use of a graphics processor, are presented. The effectiveness of the proposed method of adaptive compression HSI is shown.
An approach for configuration of the equivalence relation
Authors: Dmitriev E A , Myasnikov V V
Published: November 2019

This paper presents an approach for feature extraction using the equivalence relation. The equivalence relation is formed using features permutations of primary data. Every feature of new representation matches to optimal permutation, that minimizes some loss function. A loss function choice depends on the kind of problem. In this paper, we consider copy-move forgery detection problem and demonstrate the effectiveness of our approach in solving this problem.
For the Jubilee of Vladimir Mikhailovich Chernov
Authors: Labunets V G , Smetanin Yu G
Published: November 2019

On April 25, 2019, Vladimir Chernov celebrated his 70th birthday, Doctor of Physics and Mathematics, Chief Researcher at the Laboratory of Mathematical Methods of Image Processing of the Image Processing Systems Institute of the Russian Academy of Sciences (IPSI RAS), a branch of the Federal Science Research Center “Crystallography and Photonics” RAS and part-time Professor at the Department of Geoinformatics and Information Security of the Samara National Research University named after academician S.P. Korolev (Samara University). The article briefly describes the scientific and pedagogical achievements of the hero of the day.
Modeling and comparative analysis of schemes for returning a payload using a space tethered system
Authors: Dong Z , Zabolotnov Y M , Li A J , Wang C Q
Published: November 2019

The multiple schemes for returning a payload from LEO using a space tethered system are designed and analyzed in this paper. The space tethered system consists of a main spacecraft, a tether, a returning capsule with the payload (or space debris) and an atmospheric probe. The simulation for the motion of the tethered system is based on a mathematical model with distributed parameters, in which the tether is considered as a sequence of point masses with one-sided elastic mechanical coupling. The aerodynamic forces acting on all parts of the tethered system including on the tether are considered in this work. The atmospheric probe is used as an additional braking device for the proposed schemes for returning the payload.
Modeling of non-stationary processes in the study of liquid media by the method of nuclear magnetic resonance in a weak field
Authors: Rukin E V , Myazin N S , Davydov V V , Dudkin V I , Rud’ V Yu
Published: November 2019

The article substantiates the necessity of developing a theoretical model to study the influence of non-stationary processes on the shape of the recorded NMR signal in a weak magnetic field. Therefore, comparison of different ways of solving Bloch’s equations to describe the shape of the recorded NMR signals using a modulation technique is carried out. Moreover, mathematical models have been developed to describe the shape of the NMR signal, considering the peculiarities of its registration using modulation techniques in a weak field. Finally, the results of calculations, obtained by proposed methods, are compared with experimental data.
Multiobjective optimization of a temperature mode in a reactor unit of gasoline catalytic reforming based on a kinetic model
Authors: Koledina K F , Zaynullin R Z , Koledin S N , Akhmetov A F
Published: November 2019

Based on the previously developed kinetic model of gasoline catalytic reforming, the temperature regimes of gasoline catalytic reforming are optimized. Several target optimization functions are considered — yield of the main product required octane number with a restriction to benzene content (high-octane component, <2% by volume), etc. The proposed two-objective optimization problem for catalytic reforming of gasoline was solved with the Non-dominated Sorting Genetic Algorithm II (NSGA-II) in Matlab software environment The optimal inlet temperatures of the reaction mixture are determined for each reactor.
Mathematical modeling of the synthesis reaction benzyl butyl ether
Authors: Koledina K F , Koledin S N , Vovdenko A G , Bayguzina A R , Khusnutdinov R I
Published: November 2019

On the basis of experimental data obtained at different temperatures, a mathematical model of synthesis of benzylbutyl ether by intermolecular dehydration of benzyl and n-butyl alcohols under the influence of the catalyst CuBr2 is proposed. Optimization of the kinetic parameters of the catalytic synthesis of benzylbutyl ether is solved by genetic algorithm using the island model of parallelizing the computational process. As a result of the simulation, the values of the rate constants and activation energies of the stages are determined at different temperatures of the reaction. Thus, the developed mathematical model within the limits of the permissible error allows adequately describing the experimental data.
Assessment of the view area of parachuted radio monitoring system and stabilization of flight under wind forcing
Authors: Voskoboynikov M A , Podstrigaev A S , Davydov V V
Published: November 2019

The paper describes a method of modelling the influence of wind on the parachuted radio monitoring system. The computer simulation is carried out using Matlab Simulink with the possibility of changing the coefficients in the process of integrating differential equations. The wind speed in the model is set in the signal generators. This allowed us to get the modelling results with a variety of wind effects. The time dependences of the angular deviation of the antenna beam from vertical with wind influences were obtained. The estimation of the radio monitoring equipment view zone on the Earth surface was obtained based on them. The recommendations for flight stabilizing of parachuting system are given with quantitative assessments.
Methodology and software for estimating target efficiency of land remote sensing satellites at the stage of design
Authors: Kurenkov V I , Kucherov A S
Published: November 2019

The paper aims to present the software developed with the purpose of estimating land remote sensing satellites and space monitoring system target efficiency indices. The essence of the approach is step-by-step simulation of the satellite orbital motion with permanent determination of the flight conditions and estimation of the satellite and the space monitoring system target parameters. Main factors affecting target efficiency are taken into consideration; they include orbital elements and the satellite coordinates variation while its orbital movement, the satellite manoeuvres in the process of its target operation, conditions of survey objects taking, characteristics of survey equipment, etc. The algorithm used is based on a number of mathematical models such as models for generating initial data on survey objects, models for choice of survey objects within the satellite swath, models for constructing land remote sensing satellites survey path, models for estimating orientation of solar cell battery panels, etc. The software has been developed in Delphi programming support environment. It enables calculation of satellites target parameters such as ground resolution, operational efficiency, surveillance frequency, productivity.
Mathematical modelling and numerical study of recirculation membrane and membrane-refrigerated systems of compressed air dehydration
Authors: Laguntsov N I , Tikhonov S N , Karaseva M D , Tishin A A
Published: November 2019

Mathematical modeling and numerical investigation of the process of drying compressed air was carried out in a hybrid membrane-refrigeration system, which consists of a compressor with a receiver, a Peltier refrigerator, and a gas separation membrane module. This system allows you to get dry air, dried to a dew point of -50°C and below without loss of compressed air since only condensed water is removed from the system. It is shown that reduced energy consumption decreases with increasing compression pressure. A comparison of the hybrid membrane-refrigerator system with a single-module membrane system has been carried out, the advantages of the hybrid system are shown.
Modified Lorenz-Malkus water wheel model: dry friction versus chaos
Authors: Karpov E A , Semenov M E , Meleshenko P A , Klinskikh A F , Pervezentcev R E , Glazkova M Yu
Published: November 2019

In this paper, we propose a model of the water wheel under dry friction (the modi ed Lorenz-Malkus system). Dynamical features of this system are investigated and analyzed depending on the dry friction parameter. Particularly, we present the analysis of stationary points, Lyapunov exponents, bifurcation diagrams, and stochastic properties of the considered system. Based on the results of numerical simulations we showed that the dry friction may serve an effective mechanism to control the chaotic dynamics.
A parallel algorithm for the simulation of controlled motion of space tether systems
Authors: Zhidchenko V V , Kovartsev A N
Published: November 2019

Simulation of the controlled motion of space tether systems differs significantly from the free motion case. Tether deployment increases its length and adds new points into the discrete model of the tether. A set of dynamic equations is expanded with equations that describe the motion of the new points. The necessary condition at each step is the consistency of the system. Tether deployment is supervised by the control system which limits the tether length. The problem arises of solving a system of differential equations with variable and increasing number of equations. In this paper a parallel algorithm for simulating the controlled motion of space tether systems is designed. The parallel algorithm provides an ability to split the tether to such number of points that the model becomes similar to the model with distributed parameters. As a result, the simulation of several modes of tether motion unavailable for other methods becomes possible. The estimation of speedup provided by the algorithm is implemented. It shows that the speedup is comparable with the more simple case of the free motion simulation. Computational experiments have been carried out for the algorithm performance evaluation.
Representation of the process of oxidative regeneration of coked catalysts in a fixed layer based on graph theory
Authors: Islamova G I , Davletova M R , Dubinets O V
Published: November 2019

Representation of processes by means of graphs allows increasing their visibility in comparison with the technological scheme. This makes it possible to facilitate the design of chemical plants, especially in the case when going from the principal graph to more complex graphs of the same production. The presented representation of chemical technology processes based on graph theory is of a purely qualitative nature. The article shows the technological scheme and the resulting graph of the process of oxidative regeneration. Quantitative regularities derived from this theory can form the basis of optimization of the oxidative regeneration.
Modelling of sprays: simple solutions of complex problems
Authors: Sazhin S , Shchepakina E , Sobolev V
Published: November 2019

Some new approaches to the solution of complex problems, focused on spray modelling, using relatively simple mathematical tools are briefly summarised. The following problems are considered: modelling of spray drying with pharmaceutical applications, modelling of heating and evaporation of suspended droplets with applications to water sprays for fire suppression, modelling of micro-explosions with automotive applications, and parameterisations of slow invariant manifolds with applications to spray ignition modelling. The modelling of spray drying is based on the assumption that the array of small suspended solid particles inside droplets can be treated as a non-evaporating liquid component. The modelling of the effect of a support rod on droplet heating and evaporation is based on the assumption that this heat is homogeneously distributed inside the whole volume of a droplet. In the modelling of a puffing/micro-explosion it is assumed that a water sub-droplet is located exactly at the centre of a fuel droplet and the temperature at the surface of the fuel droplet is fixed. In the presentation of slow invariant manifolds in parametric form these manifolds are found using asymptotic expansions.
Critical travelling wave solution in one singularly perturbed parabolic equation
Authors: Shchepakina E , Sobolev V , Zhang L
Published: November 2019

In the paper, we consider a new type of travelling waves, a profile of which is a pure slow heteroclinic canard. To construct the profile we use the so-called canard cascade. Such travelling waves are critical because they are a watershed between travelling waves of different types and simulate critical phenomena in various applied problems.
Identification of exponential trend models with fractional white noise
Authors: Ivanov D V , Chertykovtseva N V , Terekhova (Zharkova) A A , Andreeva E A
Published: November 2019

The paper suggests algorithms for identifying parameters of exponential trend models in the presence of fractional white noise. The paper considers three types of models that are solutions of a homogeneous linear differential equation of the second order. Identification of the solution of a differential equation makes it possible to increase accuracy by taking into account a priori information about the nature of the roots of the differential equation and initial conditions. However, identification of the solution is fraught with difficulties due to nonlinearity in the parameters of the obtained solutions. Two-step algorithms are proposed, allowing to determine the estimates of the parameters of the considered trend models. Test examples showed high accuracy of the estimates obtained using the developed algorithms.
Computational and experimental study of mixed mode loading of the cracked semi-circular disc under bending
Authors: Stepanova L
Published: November 2019

Numerical and experimental works are performed on the mixed-mode I/II brittle fracture by two types of edge cracked semicircular bend specimens. The first type is edge cracked semi-circular bend (SBC) specimens with vertical and inclined notches. The second type of specimens is semi-circular samples in which the contribution of mode I and mode II components varies by changing the bottom loading support. In the test numerical program fracture tests were conducted at crack inclination angles of 0, 10, 45, 49, 50, 80 degrees. The stress intensity factors for Mode I and Mode II loading and T-stresses are obtained numerically in FEM package SIMULIA Abaqus/CAE. The results of FEM modeling are compared with the experimental results obtained by the photoelasticity method. The experimental approach based on the photoelasticity method allows us to observe the von Mises equivalent stress distribution in the whole specimen and confirm the FEM studies performed. The comparison shows that in the specimens the pure mode II loading can’t be realized. Analysis of numerical studies and the isochromatic fringe patterns allows us to conclude that in the semicircular disc the mixed mode loadings are realized for all angles from 0 to 85 degrees. The pure mode II or sliding fracture can’t be created by so- called mode II loading in disc-type specimens SCB, because there are opening displacements observed for all the specimens investigated numerically and experimentally.
Microstrip antenna design for arrays generating OAM mm-wave radio signals
Authors: Abdrakhmanova G I , Grakhova E P , Voronkov G S , Bagmanov V Kh
Published: November 2019

The paper is devoted to the development of the single antenna as an element of the array, intended for radiating electromagnetic fields with different orders of the orbital angular momentum (OAM) in the band 77 ÷ 78.5 GHz. Multiplexing by OAM provides more opportunities for safe data transmission and increases the quantity of the simultaneously transmitted channels. The antenna design takes into account the special requirements for its structure, imposed by its practical usage in the array. The modeling process includes calculating the dimensions, selecting the suitable materials (Rogers RO 3003) and components, simulating with the software and analyzing the following characteristics: VSWR, return loss S11, input impedance, and radiation pattern. The designed antenna’s configurations correspond to a half-wave dipole, fed by coplanar waveguide port and matched to 50 Ohm impedance. The VSWR for all cases is less than 1.8, the radiation pattern is quite wide. The shape and size for the proposed antennas provide an easy combination of such elements in the array, including the issues of the feeding lines simplicity. The application areas are described.
Mathematical simulation of the process of putting a connective insert into the orifice in a three-layered composite structure
Authors: Vashukov Yu A
Published: November 2019

This article provides the reader with the mathematical model determining the dependence of design parameters of embedding of a connective insert in a three-layered composite structure on its strained state at the outer diameter. Insert material is assumed to be a plastic body with nonlinear hardening. The model is adapted for implementing in the standard finite-element software ANSYS Mechanical used for numerical simulation of the process of embedding of the connective insert.