Software & Systems

Articles of journal № 4 at 2020 year.

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1. Issues of construction and application of knowledge basis in designing and production of innovative objects [№4 за 2020 год]
Authors: R.I. Solnitsev , G.I. Korshunov , Do Xuan Cho , Do Hai Kuan
Visitors: 4965
The paper discusses the principles of building and applying a knowledge base (KB) for innovative ob-jects. The paper describes the construction and application of knowledge base in designing and produc-tion on the basis of an example of a closed control system for the neutralization of exhaust gases of transports, which is an innovative object in the field of the functioning of Nature–Technogenics control system. The authors substantiate the choice of a closed control system for the neutralization of exhaust gases of transports as a standard for innovative design and production facilities. The design and production process of this object will be built on a knowledge base, which includes the development of principle diagrams and circuits, structural solutions and documentation, software, production, assembling, and adjusting of prototypes. In the knowledge base, there must be data and knowledge to design and produce research objects. So, for the circuit design stage, an electrical scheme is introduced for a closed control system for the neutralization of exhaust gases of transports, which developed by PCAD design tools in accordance with the established standards stored in the knowledge base. CAD and PPAS tools for the next steps will ensure the calculation of IPC standards also through the knowledge base, which includes the de-velopment of design solutions and documentation for the production of printed circuit boards and oth-er elements, and PCBA verification. The development of project documentation at subsequent design stages is also based on a knowledge base. At the same time, the structure fragments stored in the knowledge base are used for new design solutions and the production of design documentation. The paper also proposes a knowledge base management system, which will allow developers to use UML notation to provide support its, receive answers from requests of "ordinary" design engineer (cir-cuit engineers, designers, technologists, testers), experts will ensure the input and control of knowledge. The user interface is also presented, in which there are fields "enter requests", "show answers", as well as control and visualization operators. The application of the developed knowledge base for the procedures into the circuit design, architectural design stages, and technological preparation for the production is shown in examples. The knowledgebase application for specific production and design sequences is made on the basis of the user's problem-oriented language when creating requests and answers.

2. Using statistical indexes to distinguish between scientific and popular science texts on the example of the works of A. E. Fersman [№4 за 2020 год]
Authors: Gorbich, L.G. , А.А. Zhivoderov
Visitors: 2315
With the development of information technology and information systems, the problem of developing methods for machine attribution of texts has become more relevant. These techniques can be used to automatically search for texts of the required genre and style, and establish authorship using computer technology. The development of our methodology was based on the hypothesis that there are structural features of the text that allow it to be attributed to a certain genre or author without taking into account the semantic content, based on the calculation of purely quantitative values of certain parameters and indices. The authors of this paper, along with other researchers, have been developing such indices and forming an optimal set of them for a number of years, and have achieved some success in this. In particular, a set of indexes was formed that allows one to cor-rectly classify texts of different authors by genre with a probability of up to 86 %. To solve the problem of automatic classification of scientific and popular science texts, the authors applied and improved a set of statistical indexes that they had previously developed for attributing other styles. The re-search material was based on the works of academician A.E. Fersman. One of the features of this author is the style duality – the presence of a large number of scientific and popular scientific texts belonging to him, which created a unique opportunity to try to solve the problem of automatic classification of text styles belonging to one author. In the course of the work, it was shown that the sample averages of statistical indices for texts of the two styles differ significantly. Using the methods of discriminant analysis, logistic regression, and ROC-curves, the authors demonstrated the possibility of automatic classification of texts of two styles and, by optimizing the set of indexes used, achieved a significant improvement in the quality of classification. A new statistical index is also proposed that allows minimizing computational costs and successfully (up to 100 % accuracy) solving the problem of classification of scientific and popular science texts, even when using it as the only factor. The results of the study were checked for texts by other authors.

3. Algorithm analysis for multiple marking of percolation clusters with a partial load of computing nodes on supercomputer systems [№4 за 2020 год]
Authors: S.Yu. Lapshina, A.N. Sotnikov, V.E. Loginova
Visitors: 5438
The paper considers the behavior of the Parallel Cluster Multiple Marking Technique in the course of simulation experiments on the problem of multi-agent modeling with a partial load of the requested computing nodes of modern supercomputer systems installed in the JSCC RAS. The Cluster Multiple Marking Technique is a universal tool that can be used in any field as a tool for differentiating large lattice clusters. It receives data as input in an application-independent format. So, at the JSCC RAS, this tool was used to study the problem of spreading epidemics. It is possible to use this technique to study the behavior of oil reservoirs, the processes of water flow through porous materials, study the spread of forest fires, and much more. In the course of simulation experiments, the authors applied a version of the algorithm for multiple making of Hoshen – Kopelman percolation clusters, which was improved on a multiprocessor system, and associated with the linking mechanism of labels. The paper provides a comparative analysis of algorithm execution time of Hoshen – Kopelman mul-tiple labeling of percolation clusters and partial and a full load of computational nodes and various values of input parameters on four main high-performance computing systems installed in the JSCC RAS: MVS-10P MP2 KNL, MVS-10P OP, MVS 10P Tornado, MVS-100K.

4. Automatic tracking method of stem cells of the brain by MRI data [№4 за 2020 год]
Author: M.V. Shustova
Visitors: 4098
The use of stem cells for the treatment of serious diseases is a promising area of modern biomedical re-search. After transplantation to the places of the disease, the stem cells presumably have a restorative effect, including reducing the foci of ischemic brain damage after a stroke, but the exact mechanism of action remains unclear. There is an urgent need to develop new effective and safe approaches to treat-ing patients by stem cell transplantation. The successful use of cell therapy is possible only after a thorough study of the interaction of cells with the local microenvironment (migration paths to organs and tissues of the body, their effect on the lesion sites) and the development of algorithms for the ef-fective use of stem cells. The combination of modern methods of magnetic resonance imaging and methods of scientific vis-ualization makes it possible to build maps of migration and distribution of stem cells after transplanta-tion. The latter is extremely important for understanding the mechanisms of stem cell action in ischem-ic stroke of the brain for the preparation and planning of clinical trials. To solve the problem of track-ing stem cells, the availability of appropriate tools is required. To date, there are a large number of software tools for processing and analyzing biomedical, but they are not enough to automatically track the pathways of stem cell migration and the dynamics of changes of ischemic stroke foci. There is a need to develop new tools to solve these problems. This paper concentrates on the automatic tracking of mesenchymal stem cell’s clusters transplanted into the brain of laboratory animals affected by an ischemic stroke. The formalization of the solution is reduced to a transportation problem. The most probable movement of clusters is visualized using cog-nitive graphics. Simultaneously with stem cell tracking, a modeling of the area of the ischemic lesion is performed. The developed toolkit provides calculations related to the unification of the brain represen-tations of various individual animals with the aim of subsequent measurement of damaged areas; per-forming deep processing and cognitive visualization associated with the scientific highlighting of the areas of interest of the researcher. The modeling and measurement results were analyzed for the effect of transplanted cells on the is-chemic stroke foci. The analysis using the developed tools showed that the stem cell’s clusters really migrate to the area of ischemic lesion, and the volume of the ischemic focus decreases with time.

5. Method of synthesis of adaptive radio technical monitoring system [№4 за 2020 год]
Author: S.V. Butsev
Visitors: 2333
Radio technical monitoring systems for various mission objectives operate in the presence of both un-certainties in the parameters of the monitored process and the uncertainty of a generalized disturbance. The author of the paper has developed a method for synthesizing algorithms for the functioning of an adaptive radio technical monitoring system, consisting of an adaptive filter and an adaptive control system. The synthesis of an adaptive filter for a monitoring input signal includes the development of a slid-ing adaptation algorithm based on a direct estimate of the filter parameters, in particular, the gain weights generated by the adaptation unit and used in the main filter of the monitoring system. The paper proposes to use a two-level structure, which includes two stages of synthesis: the main control loop (optimal controller) and the adaptation loop (adaptive controller). The optimal controller is synthesized on the basis of the principles of the theory of optimal control of stochastic processes, provided that the parameters of the control object of the radio engineering tracking system are constant and known, and external disturbances do not change (or are absent). The synthesis of the adaptive con-troller is carried out for the case of the simultaneous presence of the uncertainty of the parameters of the control object of the radio technical monitoring system and external disturbances acting on it (model of disturbances of the control object of the radio technical monitoring system), based on the re-current modification of the least-squares identification method. The proposed approach makes it possible to formalize the problem of the functioning of an adaptive radio technical monitoring system under conditions of uncertainty of generalized disturbance parame-ters. New relationships are obtained for the evaluation of gains of an adaptive filter and an adaptive regulator transmission matrix. The adaptive radio technical monitoring system developed on the basis of the proposed method en-sures efficient functioning within the formalized quality description on the basis of the indicator de-termined by the quadratic function which characterizes the accuracy of the system operation and its control costs. The paper provides some efficiency evaluation results of the synthesized adaptive radio tracking system functioning.

6. Method of functioning of the onboard radar system while ensuring their stealth operation on radiation [№4 за 2020 год]
Authors: A.V. Bogdanov , D.V. Zakomoldin , S.I. Akimov
Visitors: 3328
The survivability of a military aircraft depends to a significant extent on the survivability of its on-Board radar station, the main areas of improvement of which are, first, the application of the multi-position principle of building on-Board radars, and secondly, increasing the stealth of its work on radi-ation. This paper sets and solves the problem of developing a method that combines these areas of in-creasing survivability. The application of the multi-position principle is implemented by combining all on-Board radars into a single system controlled by the on-Board radar of the leader aircraft, which is determined in advance and serves as a point for processing radar information received from the on-Board radars of all the group's aircraft and issuing information to all the group's aircraft about the re-quired parameters of their on-Board radars. Secrecy operation of the system of airborne radar at the ra-diation detection group of enemy aircraft, equipped with electronic intelligence stations, implemented by means of reception on each side of the radar system information from the aircraft-leader about the required parameters, their on-Board radars, namely the values of the average radiation power of the transmitter, the time of coherent accumulation in the receiver and the time of irradiation of air targets and the formation of current data values of managed parameters of the onboard radar so that the differ-ence between the required and current values of the onboard radar parameters is zero. Held on Board the aircraft-leader calculations given in this paper, the results of these calculations for each on-Board radar systems as well as manage settings of each onboard radar systems allow you to control the signal-noise generated at the input of the receivers of all stations of electronic intelligence of the enemy, and thereby to ensure the secrecy of the operation of the onboard radar system for radia-tion with a given probability upon detection of a group of enemy aircraft equipped with radio engineer-ing reconnaissance.

7. Lorentz attractor simulation [№4 за 2020 год]
Authors: F.V. Filippov , A.M. Struev , A.L. Zolkin
Visitors: 6117
This paper describes the mechanism that allows applying the Scilab system during dynamic systems simulation with kept high accuracy of the obtained data, based on the example of the Lorentz attractor build-up. The Lorentz model is a real physical example of dynamical systems with chaotic behavior, which differs from other created artificial systems. Over time, it was possible to find out that the law worked out by Lorentz has extreme importance, since it characterizes both processes in turbulent flows and processes in the laser physics and hydro-dynamic systems, as well as in complex processes of biology and chemistry. In the literature dedicated to the numerical study of the Lorentz system with classical values of its parameters, conclusions are of-ten made about the structure of the attractor based on data obtained from a computational experiment (for example, the statement that the attractor contains cycles). The program proposed for consideration by the authors consists of two main parts. The first part regulates the creation of the user function solv_lor (n), which characterizes the system of differential equations that simulates the Lorentz attractor. The second part of the listing contains a call to the creat-ed user function solv_lor (n). The paper contains the specific changes in the behavior of the Lorentz system using various values of the r parameter. Graphic illustrations that reflect the results of simula-tion using various values of the r parameter are also given in the article. Significant changes in the tra-jectory have for the large values of the parameter been found. The program sets the user function Lorenz (t, y). The numerical methods have been used in the work with this function in order to solve the system of ordinary differential equations. Moreover, the system allows performing the graphical modeling of solutions at a qualitatively high level. A set of graphical tools is provided for the dynamic editing of graphs and the management of graphic window parameters. The computer experiments carried out have proved the simplicity and convenience of using the Scilab system for modeling dynamic systems while maintaining the high accuracy of the results ob-tained.

8. Simulation of the heat conduction process using cellular automata systems [№4 за 2020 год]
Authors: S.P. Bobkov , E.G. Galiaskarov
Visitors: 3370
The paper concentrates on the use of discrete dynamic models as an alternative to the classical meth-ods of studying thermal processes in chemical technology. An adequate description of heat transfer phenomena is a hugely important problem, both in theoret-ical terms and from the standpoint of the practical use of thermal processes. In addition, modern teach-ing methods require the introduction of electronic textbooks, virtual laboratory workshops, simulation programs, which also need a correct description of the phenomena under study. The classical approach to modeling heat transfer in a continuous medium involves the use of heat conduction equations, in which the thermophysical characteristics of materials are usually constants. Taking into account the effect of temperature on the characteristics of materials leads to the need to study nonlinear equations, which causes significant computational difficulties. In this regard, it be-comes expedient to use fundamentally different approaches to modeling thermal conductivity, one of which is models based on systems of cellular automata. Discrete dynamic models in the form of deterministic cellular automata systems are used. In this case, a continuous medium is considered as a set of interacting elements whose behavior is completely described by local functions. The paper describes the main approaches and general methodology for the development of discrete models. The examples of cellular automata systems use for simulation of nonlinear heat transfer processes are considered, taking into account the heterogeneity of the material and the presence in the material of volumetric sources of variable power in it. The obtained data of discrete simulation are in good agreement with the results of using the classi-cal approach and do not contradict the generally accepted views adopted in the theory of thermal phe-nomena. The paper shows the features of the discrete approach in comparison with the use of partial differential equations with nonlinear coefficients, shows the advantages and disadvantages.

9. Optimization of lighting calculation for interior scenes for stochastic ray tracing [№4 за 2020 год]
Authors: S.V. Ershov , I.V. Valiev , A.G. Voloboy
Visitors: 2809
Lighting simulation and the creation of realistic images increases the efficiency of building design. The most common method used for this simulation is bidirectional Monte Carlo ray tracing. The paper discusses the improvement of the Monte Carlo ray tracing which optimizes the emitting of rays from a natural light source for interior scenes. The proposed algorithms can accelerate the con-vergence of the method, i.e. reduce the noise remaining after a certain simulation time, and thus im-prove the final image of the virtual scene. These algorithms are effective for indoor scenes illuminated externally through windows or other openings. Rays from light sources are generated so that they are directed into these windows, deliberately cutting off the rays that do not illuminate the interior. In other words, the number of rays increases for directions that contribute to the image formed by the camera. The first of the proposed algorithms require supplementary user specifications for marking win-dows, transparent doors, or other openings through which light can enter into interior rooms. The sec-ond algorithm is fully automatic. It belongs to a wide class of algorithms for finding and using the opti-mal PDF (Probability density function) in stochastic ray tracing. The second algorithm provides less acceleration for simulation but does not require action from the user, in particular, eliminating the po-tential error that can lead to underestimation of the room illumination. The paper provides the mathematical justification of the correctness of the proposed algorithms. The examples show that the proposed approach allows calculating the image with the desired quality several times faster.

10. Optimizing speed for VPN providing the possibility of telework using routers powered by ARM CPU [№4 за 2020 год]
Authors: S.V. Andreev , A.A. Khlupina
Visitors: 3902
This paper devotes to the problems of optimizing VPN speed connections when using routers with ARM processors. In the current context, many enterprises and institutions around the world raise the urgent issue of ensuring access for employees, as well as a remote branch or unit, to the resources of the head office local area network. The paper discusses the possibility of connecting employees through an encrypted VPN channel using modern home routers using ARM processors. With this ap-proach, all remote user devices are automatically connected to the local network resources of the head office, enterprise, and there are no needs for enterprise IT specialists to configure each of the user’s device individually. The paper considers a solution to a key problem of this approach, namely, ensuring the maximum speed of an encrypted VPN connection, and, therefore, accelerating the software components of routers included in its internal software (firmware) to provide a high-speed encrypted VPN connection. We consider the optimization of the speed of encryption and decryption algorithms using the features of the target processor of the device, such as parallelizing the execution of processor instructions using SIMD (Single Instruction, Multiple Data), general improvement of router performance when using op-timal compiler options, non-traditional use of PCI hardware encryption devices, use of alternative op-tions for modern private virtual networks (VPNs) for routers with a relatively low clock cycle frequen-cy of the ARM central processor (CPU), but containing more than two cores, while providing VPN channel multithreading.

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