bluuebunny/crossref_metadata_2025 huggingface dataset:
Three-dimensional modeling of processes in a traveling-wave tube terahertz range
Authors: Nguyen Ch.Z. , Alikov S.A. , Shein A.G. , Kovtun D.G. , Ilyin E.M.
Published: November 2021

Mastering the terahertz range promises many opportunities for practical application, in this regard, the problem of optimizing existing and creating new amplifiers and generators operating in this frequency range does not lose its relevance. One of the possible approaches for solving the problem under consideration is provided by electrovacuum electronics, where a traveling wave lamp can be especially noted due to the combination of its characteristics in terms of power and bandwidth. Goal. Creation of a threedimensional model of the device, based on the finite difference time domain (FDTD) method for Maxwell's equations and the cloudin-cell (CIC) method, followed by a series of numerical experiments to study the characteristics of the device with the given electron flow parameters and space configuration interactions. Results. The results of modeling a traveling-wave tube of the O-type in the terahertz range are presented using the example of an amplifier with a retarding structure of the double comb type with a strip electron flow. It is shown that the presented algorithm can be used to simulate processes in a slow-wave structure of a complex type with an input and output waveguide and absorber inserts. The power gain is estimated for a system with an absorber of various lengths, and the absorber length is optimized. Practical significance. The field of application of the proposed model is the study of processes in electrovacuum devices with the aim of both modernizing existing microwave amplifiers and generators in the terahertz range, and developing new devices.
Electromagnetic waves between mutually moving radiator and receiver
Authors: Tarabrin G.T.
Published: November 2021

A flat one-dimensional field of electromagnetic waves described by Maxwell's equations is considered. In the framework of solving the Cauchy problems of hyperbolic equations, we study the period of harmonic waves on the receiver for different versions of the relative motion of the radiator and receiver. Formulas for the ratio of the periods of generated and received waves are obtained. It is found that when the relative motion of the radiator and receiver is relative to each other, the receiver receives waves of a different period that creates a generator on the radiator. When the radiator and receiver approach, the wave period shortens, and when they are removed from each other, the wave period lengthens. These phenomena are known to practical physics and are called blue and red shifts. The formulas allow us to see that at a constant velocity of mutual movement, there is a qualitative difference in the periods of received waves, when the radiator is moving and the receiver is stationary, and, conversely, when the receiver is moving and the radiator is stationary. For all variants of the mutual movement of the radiator and receiver, the Doppler effect formulas are obtained. What is remarkable is that the Doppler effect does not change because the radiator is moving and the receiver is stationary, or, conversely, the receiver is moving and the radiator is stationary. This is also observed when the radiator overtakes a moving receiver or, conversely, the receiver overtakes a moving radiator. It is concluded that mathematical models of the detected physical effects are a manifestation of the physical properties of the medium in which electromagnetic waves propagate – a medium called the emptiness. In the near future, humanity will enter deep space and reach velocities comparable to the light velocity. This will make it possible to conduct experiments with vehicles moving relative to each other and obtain results of direct observations of the physical properties of the emptiness. These experiments are extremely important because they will lead humanity to the knowledge of the properties of what has become, as it can be assumed, the basis of all that we directly or indirectly observe in the world around us.
Hybrid integrated circuit design for particular application
Authors: Divakova Y.A.
Published: November 2021

An important achievement of microelectronics is the development of a new electronic component base, in particular, integrated circuits. In the development of radio electronic means, the main difficulty is the production of microcircuits, which play a decisive role in the functioning of the printed circuit assembly. The actual problem is that it is necessary to develop a microcircuit for a certain RES, since there is no way to choose from those existing on the market. The article describes in detail the algorithm for the development and design of ICs for private use, which meets the given electrical and technological requirements of the device. A technique for calculating the geometric dimensions of resistors and capacitors is described. The developed IC contains precision resistors and capacitors that are not possible to manufacture in production. As a result, these resistors will be made in the form of a trimmer structure, the capacitors will be made in the form of a hinged structure. The article describes in detail the algorithm for their calculation, as a result of which all the data for their manufacture is obtained. A detailed calculation of the geometric dimensions of the trimmer resistor, thin-film capacitors and resistors is provided. The development of the design and technology of a thin-film hybrid IC is carried out in three stages. The stated algorithm for the development of ICs is universal for all types of microcircuits, it solves the problem posed – it allows the development of ICs with the required characteristics and is possible for implementation in production.
Comlexed RF-module with synchronized generators M-type
Authors: Skripkin N.I. , Shmelev A.V. , Pronikov A.I. , Ivanov I.M.
Published: November 2021

On the basis of previously carried out works [2, 3], it has been established that the most effective way for coherent summation of the power of two generators with a waveguide output is to use a waveguide 3-decibel bridge as an adder. In this case, the output power of the synchronized device within the synchronization band can reach 95% of the total power of the generators. Purpose of the work is to describe the installation «microwave module», which uses the method of coherent summation of the powers of two magnetrons in the power adder. Mutual phased synchronization of two magnetrons is provided by a phase shifter, matching is provided by a short-circuiting piston. The summed signal is sent to the output (antenna) path of the radar. The microwave generator module is designed to generate probing pulse signals in a multifunctional receiving-transmitting radar measuring complex. For the first time in Russia, JSC «Pluton» has created a «microwave module» installation in the 2-centimeter wavelength range, which makes it possible to use the principle of coherent addition of the powers of two commercially available magnetrons. The installation cost and manufacturing time are many times less than those for a newly developed magnetron with the parameters presented in this article.
Features of adjustment of the cochlear implantation system during operation and in postoperative period
Authors: Egorov А.I. , Glukhovskiy Е.М.
Published: November 2021

Background. Hearing restoration is an important process to ensure patient comfort and socialization of a person in society (especially a child). So, the purpose of this study was to identify the possibility of monitoring the function of the cochlear in cochlear implantation, as well as to determine the peculiarities of setting up the cochlear implantation system during surgery and the postoperative period. Results. The article demonstrates the possibility of monitoring the cochlea function during the cochlear implantation process, as well as setting up the cochlear implantation system. The authors have demonstrated options for traumatization during surgery and, accordingly, complete hearing loss. The possibilities of avoiding such effects are also considered. Practical application. A deep study of the cochlear implantation process and all kinds of complications during surgery allows researchers and practitioners to avoid mistakes that will certainly affect the quality of life of patients.
The applications of medical thermography in alfitherapy
Authors: Pronin I.V. , Shcherbakov M.I.
Published: November 2021

Recently, medical thermography has attracted more and more attention from physicians and physiologists, especially in the study of complex diseases. Thermograms show the distribution of thermal fields, corresponding or not corresponding to normal thermography of specific areas. The presence of a pathological thermal picture indicates a certain pathology. Medical thermography makes it possible to conduct an examination in a short time (5-10 minutes) with the construction of accurate heat maps and is a safe method of primary diagnosis. Infrared thermal mapping provides a study of the development of a thermoactive process in time, which increases the diagnostic capabilities of the method, especially in the early stages of disease development. The aim of this work is to study the possibilities of medical thermography in the treatment of malignant meningioma by the method of alfitherapy. Alphitherapy (algo – algae, phyto– plants) is a direction in medicine, veterinary medicine, cosmetology, which is distinguished by the fact that it allows you to completely restore the entire body and get rid of hormonal, chronic, acute and concomitant diseases due to a proper balanced diet, which consists of algae, plants, macro- and microelements, vitamins with the presence of plant microorganisms. The data obtained as a result of many years of research indicate that alpha drugs contain a rich set of biologically active substances with versatile pharmacological activity, which are successfully used to treat a wide range of cardiovascular and oncological diseases, injuries and other health disorders. The results of application of the method of medical thermography in alfitherapy based on the portable thermograph IRTIS-2000 ME are presented. A patient was considered whose results of thermographic examination revealed malignant meningioma (brain cancer). As a result of the use of the alfitherapy method, the malignant meningioma was completely cured without surgery. A description of the biological mechanisms of alfitherapy and alfitherapeutic action for the treatment of cardiovascular and oncological diseases is given. The areas of application of medical thermography in medical diagnostics are presented. It has been shown that the use of medical thermography allows non-invasive primary diagnostics and monitoring of the state of human health, and alfitherapy allows effective non-surgical restoration of the whole organism, regardless of nosology.
The difference between the adaptive mechanisms of the human body when climbing to a height of 5000 m in the altitude chamber
Authors: Bragin L.Kh. , Goncharova A.G. , Bragin D.L. , Nosovsky A.M.
Published: November 2021

Despite the fact that the behavior of the human body when exposed to hypoxia has been sufficiently studied, a number of issues need further study. Identification and classification of the body's typical reactions to specific changes in environmental conditions, primarily related to the performance of activities within the framework of extreme professions, remain the actual problem. The objective of the study was to identify changes in the state of the main indicators of the cardiovascular system – blood pressure (BP), heart rate (HR) and respiratory rate (RR) – in individuals with different background values of these indicators when exposed to conditions of high-altitude hypoxia. After the study of 43 healthy male volunteers aged 30–35 (conducted according to the original method of raising the subjects in the pressure chamber to a height of 5000 m) it was found the subjects showed different "patterns" of changes in BP, RR and HR, depending on the background values. BP increased in proportion to its background values. The change in RR had a complex dynamics. And the HR increased to approximately the same values in individuals with different values of background indicators. The revealed patterns of changes in BP, RR and HR should be taken into account when selecting individuals for activities associated with being in conditions of high-altitude hypoxia. The patterns will also make it possible to optimize the work and rest time of persons already engaged in such activities, depending on the physiological characteristics of their body.
Prediction of perioperative parameters of laparoscopic organ-sparing interventions on the kidney taking into account the surgeon's "learning curve"
Authors: Gridin V.N. , Kuznetsov I.A. , Gazov A.I. , Sirota E.S.
Published: November 2021

The paper considers an integrated approach for constructing models for predicting the perioperative parameters of laparoscopic kidney resections, which include the duration of the operation, the time of thermal ischemia, and the glomerular filtration rate 24 hours after the operation. The approach is based on the principle of expanding the feature space, extracted from the analysis of the surgeon's "learning curve" data when mastering laparoscopic kidney resections. The aim of this work is to predict the main perioperative parameters that have the most significant impact on the surgical tactics of treatment at the stage of planning surgery. New methods have been developed for identifying significant parameters that take into account the complexity of the operation and the qualifications of the surgeon based on his “learning curve”. The parameters to be distinguished include: “complexity of the operation” based on nephrometric indices (RENAL, PADUA and C-index); the average value of the predicted perioperative parameters of surgical interventions depending on the complexity; slope and standard error based on the regression line of predicted perioperative parameters. Models were developed for predicting the perioperative parameters of laparoscopic organ-preserving kidney interventions using modern approaches based on machine learning, which are based on the algorithms “decision trees”, “multilayer perceptron”, “Naïve Bayes”, “logistic regression”. A comparative analysis of the quality of the developed models was carried out, as a result of which the best result was obtained using the “logistic regression” algorithm. The F-measure was used as a metric. A comparative analysis of the developed models was carried out to assess the impact on the final quality of the new selected features. For the predicted parameter “time of thermal ischemia” the increase was from 9.68% to 16.68%; for the predicted parameter “duration of surgery” the increase was from 2.76% to 4.08%. At the same time, for the predicted parameter “GFR in 24 hours” there was no significant increase, and for the “multilayer perceptron” algorithm it turned out to be negative. The obtained forecasting models can be used in applied software solutions that act as decision support systems in determining the surgical tactics of treating patients with localized formations of the renal parenchyma. Such software solutions can be implemented as a web service or as a separate program.
Register of the human brain acoustic area spectrum
Authors: Shabanov G.A. , Rybchenko А.А. , Lebedev Yu.A. , Lugovaya Е.А.
Published: November 2021

Abstract. Last years, there were developed methods based on the human brain and body acoustic signals application. We consider human brain micro vibrations as an ancient, highly reliable, relatively rapid channel of the central nervous system with all the organism cells and structures. There is offered a method of the human brain acoustic area spectrum analysis and registration. Experimental sample “Register of the human brain micro vibrations spectrum is developed. The model of the human brain acoustic area generation is offered – neurovascular reflex and related with human brain blood vessels smooth muscularity nerve cells metabolism. In comparison with classical EEG, it is demonstrated that acoustic encephalogram also reflects human brain neuroreflex activity. Piezoelectric sensors, which feature in silicone membrane existence, are investigated. Such type of construction allowed to register human brain mechanical vibrations in the gamut from 0.1 up to 27 Hz. Spectral analysis is specific in that signal integration time is 160 seconds. Meanwhile, 12600 spectral harmonics of the human brain reticular activating system were reliably extracted. For convenience, all the acoustic area spectrum of the human brain was shrunk into segmental frame of reference which is frequency structured matrix of functional conditions multiplicity “multiple arousal” of 24х625 frequency cells size. All the developed technologies and device might be used for the organism adaptation estimations, psycho-emotional conditions estimations and functional-topical diagnosis of the internal parts of the human body.
Influence of digital filtering parameters on the pulse waveform in reflectance photoplethysmography
Authors: Lapitan D.G. , Glazkov A.A. , Rogatkin D.A.
Published: November 2021

Photoplethysmography (PPG) is an optical method for recording pulse wave (PW) propagating in the tissue microvasculature. As a rule, filters with infinite impulse response (Butterworth, Bessel, etc.) often used in PPG signal processing introduce distortions in the PW signal. At the same time, the filtering parameters for a more accurate reproduction of PW have not yet been substantiated. The aim of this work is to study the influence of digital filtering parameters, such as bandwidth and filter order, on the pulse waveform. In the study, a digital bandpass Butterworth filter was used. The lower cutoff frequency of the filter varied from 0.1 to 1 Hz, the upper cutoff frequency varied from 2 to 10 Hz and the filter order – from 2nd to 6th. It was found that an increase in the lower cutoff frequency of the bandpass filtering leads to a decrease in the amplitude of the reflected diastolic wave and distortion of the front of the direct systolic wave. A decrease in the upper cutoff frequency leads to damping of the dicrotic notch and a phase shift of the PW. Increasing the filter order decreases the reflected wave amplitude. The minimal distortions of the PPG signal were observed at the lower cutoff frequency of 0.1 Hz, the upper one at 10 Hz and the filter order equal to 2. Thus, these parameters of a bandpass filtering can be recommended for processing PPG signals for a more accurate morphological analysis of PW. The obtained results make it possible to create devices for PW analysis with substantiated medical and technical requirements for filtration parameters.
Computer system for metrological testing of location sensors used to monitor the patient's condition in magnetotherapy
Authors: Gurzhin S.G. , Nguyen V.L. , Shulyakov A.V.
Published: November 2021

Non-contact monitoring of vital signs of a person is a reliable and safe way of promptly obtaining objective diagnostic information about the current physiological state of a patient during surgical operations, physiotherapeutic procedures or during sleep. The absence of direct contact of the sensors with the patient's body makes it possible to exclude the influence of a number of interfering factors, such as a violation or weakening of contact, which can lead to a deterioration in the quality of signals from the output of the sensors, a long-term location of the sensors on the body can have a psychological effect on the patient, changing his condition and thereby distorting the treatment method, etc. In order for the results of monitoring and diagnostics to be reliable and guaranteed accurate, it is necessary to carry out periodic metrological certification of location sensors, especially since many of them are of foreign production and their characteristics are either not standardized or do not meet the requirements of their operating conditions. Therefore, the tasks of developing methods and means for carrying out metrological tests of non-contact sensors for medical purposes are becoming urgent. Purpose – to show the possibility of implementing automated metrological tests of location sensors for medical use based on a personal computer and publicly available standard hardware and software. A method has been developed and implemented for conducting metrological tests of location sensors based on a personal computer, a digital dynamic measure of linear displacement, virtual measuring instruments, laser and ultrasonic sensors, as well as determining conversion errors in the LabVIEW environment. As an exemplary measuring instrument, it is proposed to use a webcam with a virtual device for recording the law of displacement in the LabVIEW Vison Development application. Full-scale experiments have been carried out, in which, using a digital measure of linear displacement, it is possible to reproduce with high accuracy almost any law of displacement and to regulate its informative parameters. Real movement signals were received with the help of virtual devices, recorded by two location sensors and a web camera. The errors of the means of registration are determined in comparison with the given digital method and analytically the law of movement. Introduction of the developed method and hardware and software for metrological certification of sensors of diagnostic channels of the systems of complex magnetotherapy «Multimag» and «Relaxmag». Carrying out automated metrological tests of sensors will ensure prompt, reliable and objective control of their actual characteristics, which means it will increase the effectiveness of treatment due to the prompt and continuous monitoring of the patient's functional state and an objective assessment of a number of important indicators.
Automated complex for remote medical examination
Authors: Kaplan M.B. , Melnik O.V. , Nikiforov M.B. , Ustyukov D.I. , Shulyakov A.V.
Published: November 2021

Elements of telemedicine are increasingly being introduced into all spheres of medical services for the population. One promising example is automated systems for remote pre-trip medical examination of drivers. However, most of the telemedicine systems used only control the basic parameters of the body provided for by law. An urgent task is to create methods and tools for a comprehensive assessment of the driver's health based on processing of a set of biomedical signals and data that allow tracking the dynamics of the functional and psychoemotional status. Purpose – development of an automated system for remote medical examination of drivers, which allows not only to monitor basic health indicators for admission to a flight, but also to track indirect signs of fatigue, stress and exposure to psychoactive substances that can provoke inappropriate behavior on the road. A microprocessor-based system for collecting and preliminary processing of information received from a set of biomedical sensors has been developed. The original modules for measuring blood pressure and pulse, non-contact temperature measurement and tremor parameters evaluating have been implemented. The set of diagnostic procedures for the pre-trip examination is implemented in a unified cycle, which ensures the complexity of the interpretation of the results. The developed automated complex and the hardware and software tools included in it can be used to conduct pre-trip examinations of drivers of public and special transport, providing an increase in the diagnostic efficiency of identifying signs that are risk factors when the driver is allowed to work.
Formation of initial projection data in reflection tomography in the implementation of technical vision
Authors: Zhilnikov A.A. , Zhilnikov T.A. , Zhulev V.I.
Published: November 2021

The known principles of active monostatic radar are based on the effect of radio wave scattering on objects located on the path of the probing signal, and the subsequent registration of a part of the wave reflected in the direction of the emitter. However, within the framework of this study, it is of interest to register objects that do not return a reflected radio echo towards the emitter. When fixing the position of an object, it is assumed that there is a possible absence of an echo signal characteristic of classical active radar with a passive response. The absence of a characteristic echo signal does not exclude its return as a result of repeated reflection inside the scene, including along other routes and from other objects. Purpose – within the framework of the implementation of technical vision in the course of tomographic observation of a complex radar scene that solves the problems of multidimensional reconstruction, a stochastic model based on the principles of tomography describing the subject area of a complex radar scene is developed. In the indicated relevance of the development of methods for radar detection of hidden objects inaccessible for registration by classical methods, a variant of using tomographic observation of a complex radar scene is proposed. In connection with the admitted lowangle and the emerging problems of an unambiguous deterministic definition, a description of the subject area of the scene from a stochastic position is proposed. In the proposed tomographic method, in conditions of limited initial data, when a deterministic approach to the reconstruction of the radar scene is not possible, an acceptable solution is sought in the stochastic description. At a given value by sampling the space, determined by the hexagonal lattice cell, the scene reconstruction is carried out by selecting and analyzing the echo signal trajectories from the possible set of proposed ones. The decision on the choice of one or another proposed trajectory and its transfer to the category of a possible solution is carried out on the basis of a preliminary calculation of the characteristics of the stochastic description.
Development of an experimental setup for intraoperative angiography system
Authors: Kudashov I.A. , Kalmykov N.V. , Alexandrov A.R. , Ryazantsev P.G. , Shchukin S.I. , Reshetov I.V.
Published: November 2021

The treatment of locally advanced tumors of the head and neck presents serious difficulties due to the difficulty of localizing growths, namely the proximity to vital organs and systems of the body (brain, large blood vessels) and the small size of the areas of intervention limits the choice of treatment methods. So, the development of helper methods and hardware of intraoperative visualization of blood vessels is relevant. So, the development of auxiliary methods and hardware means of intraoperative blood vessel imaging for objective assessment of adequacy of blood supply and differentiated recognition of anatomical structures is especially relevant in biomedical optics. The aim of the work is to create an experimental setup for the development, testing and modification of the algorithms for improving the quality of the image of blood vessels against the background of surrounding tissues by optical method. The article is devoted to technological and program features of developing and creating an experimental setup for intraoperative imaging. Clinical problem of the necessity of vessel imaging has been established. Current state of intraoperative vessel imaging has been analyzed. Structure of the setup has been determined. The requirements for parts of the setup have been formulated. Usage of the chlorophyll as a new liquid for blood substitution has been experimentally justified. A MATLAB-based model for quality evaluation of functions of the setup has been developed. The experimental results obtained in the article are of great practical importance for the development of a biotechnological system for intraoperative vessel imaging.
Synthesis of biocompatible calcium-phosphate compositions in ultrasound field
Authors: Akopyan V.B. , Gorshenev V.N. , Budoragin E.S. , Bambura M.V. , Dragun M.A.
Published: November 2021

Introduction reflects the great interest of practical restorative medicine in artificial structures that mimic the structure and properties of natural bone tissue that are made from biocompatible composite materials suitable for restoring the integrity of bone elements of the musculoskeletal system. The Introduction also contains the physicochemical foundations and approaches to a new ultrasonic technologies providing accelerated production of a biocompatible composite material, precisely hydroxyapatite particles in a collagen matrix. Experimental part contains a description of methods and equipmets for accelerated production of a hydroxyapatite suspension in the field of a hydroacoustic emitter, which ensures that the cavitation threshold at room temperature is exceeded, at which intense acoustic vortex microflows provide a decrease in diffusion restrictions, accelerating the interaction between reacting components. The reaction is carried out with the simultaneous supply of an aqueous solution of calcium monophosphate hydrate and a suspension of calcium hydroxide. The resulting finished product is separated using an ultrasonic self-cleaning filter, where the same, by nature, microflows allow the implementation of a continuous accelerated separation of synthesized particles in an ultrasonic self-cleaning filter of the installation, where, after separation, the precipitate is also subjected to cleaning. The resulting particles of hydroxyapatite mixed with the solution collagen and homogenized in an ultrasonic field at frequency of 22 kHz and an energy density in the reaction volume from 1 to 10 W / cm3. Obtained homogenate can be easily used to create various implant designs with predetermined sizes and shapes and after freezedrying was transformed in biocompatible composite with a porous structure. To control biocompatibility, samples of this composite in form of thin plate was sewed under the skin into the scruff of white lab rats. A suspension of hydroxyapatite mechanically combined with the collagen during 30 s homogenization by ultrasound at frequency of 22 kHz and at energy density of 3 W / cm3, form a complex that is freeze-dried, after which it can be used to form the biocomposite body with porous structure and with given dimensions and shapes. Subcutaneous implantation of plates of a calcium-phosphate biocomposite with a biodegradable polymer collagen, into the scruff of a laboratory white mouse showed its good biocompatibility with tissues of a living organism, without causing either immediate or delayed adverse events in them.
Implementation of touch screens in the crew cockpit information and control field using the ARINC 661 standard
Authors: Greshnikov I.I. , Zlatomregev V.I.
Published: November 2021

This article discusses the problem of using touch screens in the crew cockpit as part of a general trend optimizing the humanmachine interface of the cockpit in order to improve the safety and quality of flights. The aim of the work is to develop a promising cockpit information and control field of a transport category aircraft based on touch screens and to analyze the feasibility of using this technology on board the aircraft. Based on the analysis of current research and trends, as well as regulatory documentation in the field of building a perspective cockpit using touch screens, a conclusion is made about the feasibility of using touch screens in the cockpit and the concept of a perspective cockpit is developed. As important elements of the concept, such interactive display pages as normal and emergency checklists, a navigation page with a flight plan, and pages of the aircraft navigation system are considered. Given the well-known problem of using touch displays in turbulence, a backup display and reconfiguration control loop is proposed. On the basis of the above-mentioned concept, an intelligent information system is being developed for prototyping a promising cockpit, taking into account the application of the ARINC 661 standard, with subsequent integration into a universal stand for prototyping the cockpit and testing the results with the participation of flight experts. The practical significance of this study is due to the significant optimization of the elements of the cockpit information and control field, as well as the potential increase in the reliability of the complex by replacing the electromechanical display controls, reducing the cost of developing the information and control field and making improvements, reducing weight by decreasing the number of wires and equipment, reducing the complexity of installation.
Radical schemes for the implementation of section structures of the RADICAL language when modeling complex purposeful system
Authors: Pirogov M.V.
Published: November 2021

Complex artificial purposeful systems and their software and hardware are characterized not only by achievements, but also disadvantages leading to significant losses. Modern automation tools do not fully cope with the existing problems. To solve the problems of complex systems, new effective tools are needed, new modeling technology. This technology should cover all significant aspects of the problem area. It seems that such technology should be based on radical modeling and the universal language of radical schemes RADICAL. A radical is a system characterized by both active (working) and passive states. Being connected with each other radicals form schemes of radicals. These schemes are constructions of the RADICAL language. In the aggregate, these schemes realize radical environment – radical model of united problem area of complex system. That is, the problem area is represented by a single global scheme of radicals. The work with such a scheme is carried out using the universal language of radical schemes RADICAL, applicable to the problem area of any complex system by constructing sections of the RADICAL language, expressed by the schemes of radicals. The purpose of the work is to consider the use of radical schemes for the implementation of the structures of sections (sequences of sections) of the RADICAL language when modeling complex system. The results of the work are descriptions of some typical schemes of radicals intended for the implementation of the section structures of the RADICAL language when modeling complex purposeful systems. Something significant sequences of sections are considered. The practice of using of structures of cross-sections of the media of radicals, expressed by the schemes of radicals, indicates the expediency of they use for radical modeling of problem areas of complex purposeful systems, for the development and modification of software and information support of such systems.
An approach to assessing the technical condition of elements and nodes of transport systems using neural network modeling methods and digital twin technology
Authors: Belousov V.V. , Druzhinina O.V. , Korepanov E.R. , Makarenkova I.V. , Maksimova V.V.
Published: November 2021

The development of intelligent methods and the development of tools for solving research problems of modeling and diagnosing the state of technical systems are relevant areas related to the introduction of digital technologies. Such problems include the problems of preparing correct data arrays for diagnosing and predicting the state of elements and nodes of transport systems. The purpose of the paper is to develop methods for preparing and analyzing data for modeling digital twins on the example of studying the temperature regime of the functioning of a railway car's axle box node, as well as choosing the architecture of neural networks for solving problems of assessing the technical condition of the axle box nodes. The features of the digital twin technology are characterized and the directions of its use for modeling and diagnostics of railway transport systems are considered. As part of the development of an approach to solving the problem of diagnosing the condition of the axle box units of railway cars, analytical dependences and generalized heat transfer equations related to changes in temperature regimes are considered. Examples of the presentation of such data on temperature series, which contain values for deviations from the normal functioning of the elements of the axle box node, are given. The choice of the neural network architecture adapted for solving the problems of estimating and predicting the temperature values of the axle box unit of the car was made. Options for preparing test data for a neural network model have been developed. The results can be used in the problems of creating algorithmic and software for preparing correct arrays of input data for technical diagnostics, in the problems of synthesis and analysis of models of intelligent systems, in various machine learning problems. The considered approach to modeling is aimed at developing methods for assessing and predicting the state of transport infrastructure elements and can be used in the development of intelligent transport systems and for improving the technology of digital twins.
Multi-channel interference source detector
Authors: Antipov V.N. , Ivanov S.L. , Koltyshev E.Е. , Mukhin V.V. , Frolov A.Yu. , Yankovskiy V.Т.
Published: November 2021

Modern radars, along with the detection and measurement of target coordinates against the background of interference, must solve the problem of detecting radio emission sources and measuring their coordinates. Detection of interference, as well as targets, in the radar is provided in the main (total) channel based on the analysis of the rangefinder-Doppler portrait of the received signal. The main disadvantage of such a detector is that the interference coming along the side lobes of the sum antenna and falling into the dip of the antenna radiation pattern may not be detected. Therefore, the problem arises of developing and analyzing algorithms for detecting interference in a radar with several receiving channels. The article discusses the logical, energy, correlation and eigenvalues of the cross-correlation matrix of the received signals interference detectors for two receiving channels. Their characteristics are given. It is shown that two-channel interference detectors based on the analysis of the eigenvalues of the cross-correlation matrix have the highest efficiency. Energy and logical algorithms are quite a bit inferior to them. The developed algorithms make it possible to effectively detect radio emission sources even when they are in the dip of one of the antenna patterns.
Method for automatic evaluation of the voice signals quality with low bit rate voice coding
Authors: Aladinskiy V.A. , Kuzminskiy S.V.
Published: November 2021

Evaluation of the VSQ is an important problem. In known methods for еvaluation the quality of analog or digital voice signals with pulse-code modulation (PCM) are used. When automatic quality assessing, it is assumed that the parameters of voice signal are determined. Then the corresponding subjective assessment of VSQ is selected. Objective methods for quality assessing are obtained by comparing the reference signal and the signal transmitted through the communication channel. To eliminate the identified contradictions, it is proposed to use an objective method that provides the assessing of VSQ in the absence of a reference signal and without conversion to the PCM format, i.e. based on the analysis of the LBR voice digital stream. The analyzed digital stream is considered as a system of random variables, which is characterized by a set of mean values and a covariance matrix that make up the pattern of input implementation. The reference pattern also includes a set of mean values and a covariance matrix. The initial data for the formation of a reference pattern are digital streams formed according to a given protocol of LBR voice coding, having the highest VSQ. The proposed method is based on calculating the divergence between the reference pattern and input implementation pattern. At the training stage, several distorted samples with a known number of bit errors are formed from the reference sample. When comparing their patterns, the divergence values are calculated, which are put in compliance with the VSQ assessment. Two approaches have been identified for making the compliance: experimental and experimental-analytical. The choice of approach is determined by the presence of initial data characterizing the VSQ for particular vocoder. Then generated compliance is interpolated. At the assessment stage for each implementation is calculated the divergence between the explored pattern and the reference pattern, which is formed from the training sample. Based on the divergence, the VSQ assessment is calculated. To test the proposed method a reference sample of digital streams obtained by compressing voice signals with a LPC-10-2400 vocoder was formed. Based on the initial data, which are presented in Recommendation-R F.1112-1, the compliance between the values of sound intelligibility and divergence was compiled by experimental-analytical approach. The obtained correspondence was interpolated by the least squares method using a third degree polynomial.
Method of measuring antenna axis ratio close to unit
Authors: Kirilyuk S.D.
Published: November 2021

On purpose to increase efficiency of an orbital-frequency resource the usage of polarization-division multiplexing (PDM) is extended in satellite communication systems. For this aim the axis ratio (AR) of polarization ellipses on satellite radio lines with circular (rotating) polarization must be not less 0,94. Nowadays widespread techniques of experimental defining AR, are based on measurements of orthogonal components intensity of electromagnetic fields created by aerials. But, at high, more than 0,85 axis ratios, the information about a difference in components intensity loses on errors of the measurements realizing these techniques. The method of defining AR, close to extremely achievable value (nearly equal to unit) is presented in the article. The basic idea of this method consists in inclusion to the measurement scheme of two identical devices (DUT), working one towards to another. Also the scheme of counter inclusion of two identical DUT, similar used for measurements, may be applied for designing antenna elements with high AR. Good coincidence of results of modeling, laboratory measurements and field tests have confirmed suitability of the offered method for the designing and testing of aerials with high axis ratio.
Features of the implementation of fixed phase shifters on coupled microstrip transmission lines with a stub
Authors: Meschanov V.P. , Sayapin K.A. , Sherstyukov D.N.
Published: November 2021

Fixed phase shifters with a phase-shifting channel based on coupled transmission lines of class II with a stub have a number of advantages in comparison with previously known structures for similar purposes. However, their practical implementation causes difficulties associated with the topological features of the structure, which, in turn, leads to a deterioration in frequency characteristics. In this regard, a numerical analysis of inhomogeneities in a class II structure with a stub and an assessment of their influence on the frequency characteristics of fixed phase shifters is required. In this work, circuitry and electrodynamic modeling of class II structure elements has been carried out, which showed that the greatest parasitic effect on the frequency characteristics of the phase shifter has a nonzero coupling coefficient of single transmission lines and an inhomogeneity localized at the junction of the short-circuited stub and the output arms of the associated transmission lines. A fixed phase shifter with a phase-shifting channel based on a smoothly stepped structure with a stub has been developed. The presented results of the study of fixed phase shifters based on microstrip coupled transmission lines of class II with a stub can be useful to scientific and technical workers engaged in the development of functional devices for the phase shift of microwave signals.
Estimating the noise immunity of spacecraft on-board repeaters and satellite earth stations under the influence of intentional interference
Authors: Pantenkov D.G.
Published: November 2021

Civil, special and dual-use satellite communication systems are used everywhere in space, land, aviation and maritime means of transmitting information to remote subscribers. At the same time, during operation of these systems, one of the main issues is ensuring the required level of noise immunity of communication channels when operating in a complex electromagnetic environment, in conditions of both unintentional and intentional interference. This article proposes a technique for estimating the noise immunity of spacecraft on-board repeaters and satellite earth stations under the influence of intentional interference based on the application of the suppression coordinate law, which takes into account the probabilities of suppressing a useful communication signal depending on the coordinates of interference points by frequency, time, radiation power. The results of calculations and graphical dependencies based on results of mathematical simulation of impact efficiency on onboard repeaters of spacecraft and terrestrial stations of satellite communication of noise barrier by frequency of interference in modes of repeater functioning both with direct transfer of signal spectrum by frequency and with its processing on board are presented. At any stage of design of communication systems in the composition of various complexes of aviation, sea, land, space bases, it is possible to obtain estimates of their noise immunity, or vice versa, when designing electronic warfare, to obtain estimates of suppression of satellite communication systems according to the probability criterion.
Radiothermal radiation method for aqueous solutions
Authors: Morozova L.A. , Savel’ev S.V.
Published: November 2021

For the first time, an ultra-high-sensitivity method for measuring radio-thermal radiation was developed and used in practice in order to establish the difference in the physical properties of aqueous solutions of substances in the millimeter region of the spectrum. The method is used to study the dynamics of the dielectric properties of aqueous solutions depending on the composition of the base substance and its concentration. The dynamics of dielectric properties establishes a one-to-one correspondence between the number and concentration of ions of the dissolved basic substance contained in water and the number of water molecules involved in cooperative interaction, which gives a consistent microscopic picture of ion-water cooperative interactions in the studied aqueous solutions of K2SO4 and Cs2SO4. The density of water molecules perturbed by the ions of the base substance contained in the hydration shell at normal concentrations is proportional to the number of ions, while the transition to weaker solutions leads to the creation of multilayer hydration shells. This means that the number of perturbed water molecules, depending on the number of ions, increases according to a law different from linear. In accordance with the experimental data, the values of the absorption coefficients of aqueous solutions were determined in a wide range of concentrations for alkali metal sulfates. It is noted that alkali metal sulfates have physical properties that generalize the dynamics of dielectric constants depending on the concentration of the base substance. A monotonic increase in the values of the absorption coefficients of solutions with a decrease in the concentration of basic substances in the region of high dilutions was established with individual dynamics for each basic substance, reflecting the total hydration changes in salt solutions. Research has shown that the proposed method for measuring radio-thermal radiation fixes a significant difference in the values of the dielectric constants of aqueous solutions at high dilutions from their values for water.