Informatics, computer technology and management. Рубрика в журнале - Siberian Aerospace Journal
Статья научная
The original method for encoding binary data streams based on QPSK quadrature phase shift keying in a wireless optical communication channel in the visible range is suggested. The algorithm for analyzing signals in the receiving tract is presented. It allows to analyze the presence of two or three pulses of different colors at the input, which will signal the presence of interference or the occurrence of "illumination". In addition, the algorithm provides a possibility of dynamic compensation of external "illumination" by changing the gain of the photodetectors and adjusting the brightness of emitting LEDs. The functional scheme of the device for realization of the offered coding method in the wireless channel on the basis of optical radiation has been developed. Given that most photodiodes are sufficiently wide-band in the visible range of light waves, to increase sensitivity of each color channel and selectivity of the receiving tract it is necessary to apply optical filters for each color channel. The most effective are interference filters made of optically transparent materials with different physical characteristics. The approach for calculating optical filters has been presented.
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Development of tunable band noise genera-tors
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The aim of the work is to develop and study the principle of operation of tunable band noise generators (TBNG) and their characteristics, a noise signal conditioner of a modular type, which provides controlling the bandwidth of a noise signal for using it as a means set-ting radio noise. It is possible to do it through the formation and radiation in the surrounding space of electromagnetic fields of the energy spectrum in specified frequency ranges, with the possibility of changing the amplitude and bandwidth of the signal. To improve performance and make them more widely used in order to provide high-quality counteraction to unauthor-ized removal (by intruders) of information on emission channels of spurious electromagnetic radiation (SER), it is necessary to create multichannel adaptive TBNGs. In the developed generators in each noisy channel, it is possible to provide power adjustment, generated noise signal and noise bandwidth control, which will improve the electromagnetic compatibility of such devices. To ensure this, it is proposed to use a design concept based on the use of con-trolled modules of noise sources with band-pass filters, which also allows you to get a noise signal uniform in amplitude.
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Development of workspace and algorithms for testing SpaceWire onboard equipment
Статья научная
For a long time, the foreign space industry has been using one of the most advanced and actively devel-oping technologies for transmitting information on board a spacecraft – SpaceWire. This technology pro-vides high-speed transmission of large amounts of information, the creation of a single high-speed data processing infrastructure for connecting sensors, data processing system elements and mass memory blocks. In Russia, SpaceWire is gradually being introduced and used on promising spacecraft. To verify the compliance of the onboard equipment of such vehicles with the requirements of the SpaceWire ECSS-E-ST-50-12C Rev standard.1 there is a need to develop the workplace described in this article. The workplace is designed so that SpaceWire onboard equipment can be connected to it and tests can be run that check cer-tain parameters of information exchange regulated by the standard. The article presents the general struc-ture of the workplace, as well as a description of each of its elements separately, together with a descrip-tion of their functionality. The article also describes the developed testing algorithms. Among them, we can single out a check for compliance with the bit error coefficient to the required value, a check for support for the header removal method by SpaceWire switches, as well as a check for compliance with the require-ments for the RMAP and STP-ISS transport protocols. The algorithms of these tests are presented in the form of flowcharts and a detailed text description. The tests themselves are implemented in the form of pro-gram code in the C language. As a confirmation of the correctness of the developed tests, practical testing of SpaceWire devices was carried out, among which two payload boards for the NORBY spacecraft can be distinguished, as well as an ultra-large integrated circuit 1931KH014 of a programmable switch for SpaceWire networks. A brief description of the testing devices used in the work is given in the form of a presentation of their functionality applicable to the testing workplace being developed.
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Differential evolution in the decision tree learning algorithm
Статья научная
Decision trees (DT) belong to the most effective classification methods. The main advantage of decision trees is a simple and user-friendly interpretation of the results obtained. But despite its well-known advantages the method has some disadvantages as well. One of them is that DT training on high-dimensional data is very time-consuming. The paper considers the way to reduce the DT learning process duration without losses of classification accuracy. There are different algorithms of DT training; the main of them being ID3 and CART algorithms. The paper proposes a modification of DT learning algorithms by means of the information criterion optimization for some selected attribute. The use of this modification allows avoiding optimization by means of enumeration search over the entire data set. The Separation Measure method is used to select the attribute. The method selects the attribute whose class-based averages are most distant from each other. Optimization of the selected attribute is carried out using the method of differential evolution, which is one of the evolutionary modeling methods designed to solve problems of multidimensional optimization. Self-configuring at the population level based on the probabilities of using mutation operator’s variants was applied for differential evolution. The classification problems were solved to compare standard DT learning algorithms with the modified ones. Algorithm efficiency refers to the percentage of correctly classified test sample objects. Statistical analysis based on Student's t-test was carried out to compare the efficiency of the algorithms. The analysis showed that the use of the proposed modification of the DT learning algorithm makes it possible to significantly speed up the training process without losses in the classification effectiveness.
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Dynamic hybrid recommendation model construction and user discovery research
Статья научная
This study tackles keyword dependency and latency in book recommendations via a hybrid model fusing collaborative filtering with matrix factorization. The results were used to build an intelligent book recommendation system (recommendation center) with a web interface. Traditional library book recommendation systems rely primarily on users actively searching for the titles they need. Their limitation lies in the large number of matching titles that appear when keywords are entered. In our study, to further improve recommendation accuracy, the recommendation system addresses the problem of professional cognitive limitations users face when making choices through similarity calculations. Furthermore, a user search module is added to the recommendation system to ensure accurate recommendations. When generating a recommendation item for a user, the recommendation system first searches related sentences, then calculates the similarity between the target user and the related user and uses the similarity value as a weight. Finally, based on the previously calculated similarity value, it performs a weighted average of the differences between all ratings. A time-decay clustering algorithm (λ = 0.85) using multi-source data achieves 41 % increase in user similarity and 35 % in new book discovery for a user. The tests demonstrate 27 % increase in accuracy with 3300 concurrent requests (5s/300ms response).
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Efficiency improving of emergency monitoring and forecasting based on the information system
Статья научная
The article is devoted to the automated information system modification to solve monitoring and forecasting problems of natural and man-made emergencies in order to increase the efficiency of its functioning, namely, to increase the execution speed of the main operations, to reduce the error probability. Monitoring and forecasting of emergencies are among the priorities in the field of population from emergencies protection, as the prevention and elimination of their consequences are carried out on the basis of these tasks. At the same time, the data collection speed, processing and analysis largely determine the efficiency of the obtained results. The existing system of monitoring and forecasting of natural and man-made emergencies, its functional model in IDEF0 notation, characteristic features, advantages and disadvantages are considered. The existing system can be improved by automating a number of tasks related to the processing, transmission and storage of large data amounts, including real time data, as well as the generation of consolidated reports on the results of monitoring and forecasting of various objects. The information architecture of the solution reviewed and the corresponding database model form the basis of the proposed solution. The IDEF0 model of emergency monitoring and forecasting has been introduced taking into account the proposed modification of the automated information system. The main operation execution time comparative analysis based on the initial and modified automated information system (AIS) using the existing hardware confirms the effectiveness of the proposed solution. Data exchange and generation automation of consolidated reports on multiple monitoring objects will simplify analysis of the obtained results and solutions development based on them aimed at prevention of natural and man-made emergencies, as well as elimination of their consequences.
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Elastic-plastic problem in the case of inhomogeneous plasticity under complex shear conditions
Статья научная
In this research, the authors solved a two-dimensional elastic-plastic problem of the stress state under com-plex shear conditions in the body weakened by a hole that is bounded by a piecewise smooth contour. The stress state of a complex shear occurs in a cylindrical body of infinite length under the action of loads directed along the cylinder generators and constant along the generators. At the same time, with a sufficiently large load, both elastic and plastic zones appear in the body. As in any problem of this kind, it is necessary to find a previously unknown boundary separating the elastic and plastic zones. Finding such a boundary is not an easy task, but the specificity of elastic-plastic problems of complex shear is that solving such problems is easier than solving simi-lar elastic problems. Apparently, for the first time this fact was noted by G. P. Cherepanov. A lot of research is devoted to elastic-plastic problems of complex shear in the case of homogeneous and iso-tropic plasticity. All articles that solve complex shear problems essentially use the representation of stresses and displacements in the elastic zone in a complex form. In this research, the problems of complex shear are solved using conservation laws. It is assumed that the yield strength is a function of the coordinates of the point where the stress state is being studied. It is known that the elastic properties of structural materials can be homogene-ous and isotropic, while their yield point and strength are inhomogeneous. This situation is observed, for exam-ple, in the case of neutron bombardment of structural materials. This research will examine exactly this situa-tion. The article presents conservation laws for equations describing a complex shear. It was assumed that the components of the conserved current depend on the components of the stress tensor and coordinates. The com-ponents of the stress tensor are included in them linearly. The problem of finding the components of the con-served current was reduced to the Cauchy-Riemann system. The solution of this system allowed us to reduce the calculations of the stress tensor components to a curvilinear integral along the contour of the hole and thus find the boundary between the elastic and plastic areas.
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Elastic-plastic torsion of a two-layer rod
Статья научная
We study the elastic-plastic torsion of a two-layer rod under the action of torque in this article. It is as-sumed that the rod consists of two layers. Each layer has its own elastic properties, but the plastic proper-ties of both layers are the same. The contact boundary of the layers is located along the ох axis. The lateral boundary of the rod is stress-free, displacements and stresses are continuous at the interface. The compo-nents of the stress tensor at a point are calculated using contour integrals derived from conservation laws calculated along the lateral boundary. Next, the second invariant of the stress tensor is compared with the yield strength. At those points where the yield point is reached, the plastic state is realized, in the rest – elastic. This allows you to build a boundary between the plastic and elastic regions. This technique pro-vides a way to calculate elastic-plastic boundaries for the main rolling profiles of rods. This is supposed to be done in subsequent works. We remind you that earlier, with the help of conservation laws, the main boundary value problems for a plastic two-dimensional medium, elastic-plastic torsion of isotropic rods and elastic media for bodies of finite dimensions were solved.
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Errors reduction while locating objects of the radio navigation system
Статья научная
The present research considers a method for improving the accuracy of the dead reckoning position of a board station based on signals from the ground-based radio navigation systems. In the radio navigation sys-tem, grounded on the signal emitted by the base fixed stations, the slave fixed stations receive signals deter-mining the moments of their arrival relative to their own time scales. On the other hand, based on the radio frequency emitting signals by the slave fixed stations, the base fixed stations receive signals defining the moments of their arrival relative to their own time scale. According to the measured moments of radio emit-ted signal arrival, time corrections are calculated to the time scales of the slave fixed stations relative to the base fixed station. Since the time correction is calculated for a time of no more than 10 seconds, a random components are excluded due to the variability of the propagation velocity of the surface electromagnetic wave due to the variability of the environmental parameters and the parameters of the near-surface layer of the electromagnetic wave propagation area. If the calculated value of the time correction of the duration of the clock interval of the generated signal is exceeded, the moment correction (up to a clock) of the formation of the modulating code of the signal emitted by the slave fixed station is performed and the calculated value of the time correction is improved by the value of the previously corrected clock duration. The corrected values of the time corrections (pre-coded) are transmitted to each of the slave fixed stations as a part of their navigation signals. The navigation information consumer receives the radio navigation signals emitted by the fixed stations, through decoding, a consumer highlights information about the mismatch of time scales from the signals of the fixed stations and measures the radio navigation parameters with heightened accura-cy due to compensation for the error of the out-of-sync radiation signals of the slave fixed stations of the radio navigation system.
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Статья научная
A lot of sets of subjects and objects in biology, industry, management can be divided into a number of classes, each of which corresponds to a certain distribution component. When analyzing a mixture of distributions, it is necessary to estimate its parameters (task 1) and to assess the correspondence of empirical and theoretical distribution functions (task 2). To solve the first problem, numerical algorithms that implement the method of moments and the maximum likelihood method are used. In this paper, the problem of estimating the distribution parameters is solved by minimizing the goodness measure by the Quasi-Newton method. The second problem is solved by comparing the empirical and theoretical distribution functions by one or several statistical goodness measures. Statistics of the distribution of these measures depends on the sample size, the method of forming data and estimating distribution parameters. The paper examines the goodness measure between Frocini and omega-square (Kramer – Mises – Smirnov). The evaluation of the statistics of the goodness measure was carried out by the simulation method based on the results of 50000 statistical tests. In each of the tests, the distribution parameters were estimated by minimizing the calculated value of the corresponding goodness measure. The results of simulation modeling allow estimating the statistics of the parameters of a mixture of distributions. The results of solving the considered problems for a mixture of two normal distributions of size 240 are presented.
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Estimation of the number of aperiodic words
Статья научная
In 1902 W. Burnside raised the issue of local finiteness of groups, all elements of which are of finite order. The first negative answer was obtained in 1968 in the article by by P.S. Novikov and S.I. Adian. Finiteness of the free Burnside group of period n was established for n = 2, n = 3 (W. Burnside), n = 4 (W. Burnside, I. N. Sanov), n = 6 (M. Hall). The proof of infinity of this group for odd n ≥ 4381 was given in the article by P. S. Novikov and S. I. Adian (1967); for odd n ≥ 665 in the monograph by S. I. Adian (1975). In relation with these results we consider the set of m-aperiodic words. Word is called l-aperiodic if there are no non-empty subwords of the form Yl in it. In the monograph by S. I. Adian (1975) the proof of S. E. Arshon (1937) of the fact that in the two-letters alphabet there is an infinite set of arbitrarily long 3-aperiodic words was shown. In the A.Yu. Olshansky’s monograph (1989) the theorem on the infinity of the set of 6-aperiodic words was proved, and a lower bound function for the number of words of a given length was obtained. Our aim is to get an estimate for the function ()fn of the number of m-aperiodic words of the length n in the two-letters alphabet. The results can be applied when encoding information in space communications.
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Evolution of heuristics for selection synthesis in a genetic algorithm
Статья научная
A method for the automatic design of selection operators for a genetic algorithm is proposed, based on the Evolution of Heuristics (EoH) approach, which integrates the capabilities of Large Language Models (LLMs) and evolutionary search. The design of selection operators was carried out on three pseudo-Boolean optimization problems, and testing was performed on 17 functions from the IOHprofiler benchmark set. Two experimental setups were considered with and without explicit knowledge of the type of problem being solved. The language model used was DeepSeek-Coder-V2, which was deployed locally using the Ollama framework. The quality of the designed heuristics was determined based on the comparison with the results of standard rank selection. The quality of the obtained solutions is compared with classical selection schemes (tournament, proportional, and rank-based), as well as with the FunSearch method, previously used to generate new implementations of rank-based selection. A comparison of various heuristics was carried out for multiple runs on each of the 17 tasks using the nonparametric Mann-Whitney statistical test. It has been shown that automatically designed heuristics have unique properties, and the lack of information about the type and structure of the problem being solved has led to a greater variety of generated solutions. Namely, in one of the launches, without information about the type of task, the designed code selects individuals whose fitness differs from the maximum by less than half the distance from the maximum fitness to the median. In other words, it is a variant of tournament selection with an adaptive tournament size based on the distribution of quality. The availability of information about the type of problem being solved led to the fact that the language model generated typical known solutions, in particular, variants of simple tournament selection. The proposed approach can be applied to other tasks of automatic design of algorithms as a whole or components of algorithms.
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Evolutionary algorithm with an autoencoder-based dimensionality reduction mechanism
Статья научная
Many modern applied optimization problems are formulated as black-box models, characterized by a lack of analytical information about the objective function and its properties. While Evolutionary Algorithms (EAs) are frequently applied here, their performance degrades in high-dimensional spaces with complex landscapes. Moreover, these algorithms require generating a large number of trial solutions for effective operation, which may be unattainable in applications with expensive objective function evaluation. To overcome these limitations, we introduce a novel EA framework centered on adaptive, autoencoder-based dimensionality reduction. The autoencoder is retrained dynamically during the search using evolving population data. The strategy relies on the parallel operation of two optimization algorithms: one works in the original solution space, and another operates in a latent space – a compact, nonlinear representation of the current population generated by the autoencoder. This design enables the algorithm to adapt to the problem's specific structure. We evaluated the method on standard benchmark problems, analyzing its convergence dynamics and sensitivity to the latent space size. Statistical significance of the results was assessed using the Wilcoxon rank-sum test. The L-SRTDE algorithm was used as the subpopulation optimization method. Numerical experiments demonstrate that the proposed algorithm enhances search space exploration in first optimization stages but, on average, is slightly less efficient than the base algorithm.
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Статья научная
In this paper the approach for external boundary of pole localization region formulation for transfer function with interval-given parameters is proposed. The boundary is formulated as analytic piecewise function of characteristic polynomial parameters of the given transfer function. Analytic formulation of external boundary of poles localization region allows to reduce computations since existing methods require iterative numeric calculations of characteristic equation roots with fixed step size for edges mapping or full interval root locus mapping as well. Formulated boundary allows to clearly describe system behavior and calculate variation ranges of performance indexes. In addition, piecewise function that constrains gives new opportunities for parametric controller synthesis for systems introduced by transfer functions with interval-given parameters. The results can find its practical application in aerospace engineering problems of mathematical analysis and synthesis for highly-precise systems of self-direction missiles. In the research the boundary formulation is performed for third order transfer function. Transfer function order was chosen due to the fact that many physical systems and objects can be described mathematically with the third order transfer function, e.g. model of missile target-seeking head with gyro stabilized drive is described with this model. The research was performed on the basis of the following step sequence: firstly, analytical solving of cubic equation applying Cardano’s formula; secondly, interval root locus edges functions obtaining, next external vertexes set obtaining and, finally, external border formulation and plotting.
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Generalized equivalent strength conditions in the calculations of composite bodies
Статья научная
Structures with an inhomogeneous regular structure (plates, beams, shells) are widely used in engineering, especially in aviation and rocket and space. It is important to know the solution error in the strength elastic calculations for composite structures using the finite element method (FEM),. To analyze the error of the solution, it is necessary to use a sequence of approximate solutions constructed according to the FEM using the grinding procedure for basic discrete models that take into account the non-homogeneous, micro-homogeneous structure of structures (bodies) within the micro-approach. The implementation of the grinding procedure for basic models requires large computer resources. This paper deals with the method of equivalent strength conditions (MESC) for testing the static strength of elastic bodies with an inhomogeneous regular structure, for which sets of different loads are given. According to the MESC, the calculation of the strength of a composite body for which the loading is set is reduced to the calculation of the strength of an isotropic homogeneous body (having the same loading as a composite body) using equivalent strength conditions. In the numerical implementation of the MESC, adjusted equivalent strength conditions are used, which take into account the error of approximate solutions. Here, the MESC is implemented on the basis of the FEM. If a set of different loads is specified for a composite body, then generalized equivalent strength conditions are applied in this case. The procedure for constructing generalized equivalent strength conditions is shown. The calculation of the strength of composite bodies according to the MESC using multigrid finite elements requires 3 6 10 ÷ 10 times less computer memory than a similar calculation using crushed basic models of composite bodies. The given example of calculating the strength of a composite beam, for which a number of loads is set with MESC using generalized equivalent strength conditions shows its high efficiency.
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Статья научная
The purpose of the study is to develop a technological process mathematical model of creating permanent joints of dissimilar materials based on electron-beam welding using machine learning algorithms. Each of the connected elements is a responsible unit of the complex device, due to this fact, strict criteria are set for the quality of the welded joint. In essence, the set task is a regression task. There are many algorithms suitable for solving the regression problem. However, often the use of one algorithm does not provide sufficient accuracy of the result. One way to solve this problem is to develop a composition of algorithms to compensate for the prob-lems of each of them. One of the most effective and potent compositional algorithms is the gradient boosting al-gorithm. This algorithm use will improve the quality of the regression model. The proposed model will allow the technologist to set the process parameters and to get an assessment of the final product quality, as well as by setting input and output values. The use of assessment methods and forecasting will reduce the time and labor costs of searching, developing and adjusting the process. A description of the gradient boosting algorithm is given, as well as an analysis of the applicability of this algorithm to the model and a conclusion regarding the areas of its applicability and the reliability of the forecasts obtained by its direct use. In addition, we consider the process of direct model training based on the data obtained as part of search experiments to improve the quality of final product. The results of the applicability analysis allow us to judge the admissibility of using the proposed method for processes that have similar statistical dependencies. The application of the proposed ap-proach will make it possible to support the adoption of technological decisions by specialists in electron-beam welding during the development of the technological process and when new types of products are put into pro-duction.
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Статья научная
An artillery shot is a complex gas and thermodynamic process of rapidly converting the chemical energy of gunpowder into heat, and then into mechanical work of moving the projectile and the recoil parts of the artillery gun. A distinctive feature of the use of aviation artillery weapons is the short time during which firing from an aircraft at a target is possible, which requires the production of not one artillery shot, but the firing of the maximum number of shells with minimal interruptions between bursts of shots. An analysis of the existing physical concepts of the processes occurring in a small-caliber artillery barrel (hereinafter referred to as the barrel) makes it possible to single out the main quantitative characteristic of the temperature state that affects the quality of the functioning of aviation artillery weapons – the temperature field of the barrel. The temperature field, high in level and gradients, formed in the barrel wall during firing, bursts and series of shots, has a significant impact on the reduction in the tactical, technical and operational characteristics of aviation artillery weapons. Therefore, the problem of synthesizing a mathematical model of thermophysical loading of a wellbore (hereinafter referred to as the model if it is clear from the context of material presentation that we are talking about the developed model) and the definition of the temperature field is of great importance for solving a number of practical applications. These include: assessment of bore wear depending on heating; analysis of the thermal strength of the barrel material; analysis of the conditions of projectile guidance along the bore and cartridge case extraction during firing; evaluation of various ways and methods of artificial cooling of shafts; determination of the safety of aviation artillery weapons by eliminating the event of self-activation of a thermally loaded cartridge located in a barrel heated by firing; ensuring the conditions for maintaining the operability of fuses, etc. At the same time, an adequate calculation of non-stationary heat transfer in the bore is difficult, due to the incomplete reliability of the initial data and the dynamics of fast processes in the use of aviation artillery weapons. The aim of the work is to improve mathematical tools that describe the thermodynamic states of the barrel based on the basic functional dependencies of internal ballistics and a dispersed combination of heat transfer methods and finite differences. Numerous and comprehensive testing of the synthesized model, comparison of the calculation results with the data of the classical theory, self-similar solutions and experimental data confirmed the reliability and predetermined the sufficient suitability of the model for its intended use as the objects of research become more complex.
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Статья научная
Fuzzy logic systems are widely used in classification problems due to their ability to handle uncertainty, imprecision, and subjectivity in data. Unlike traditional “crisp” methods, fuzzy logic allows input features and output classes to be described in terms of linguistic variables – such as “high”, “medium”, and “low” – making models more interpretable and aligned with human reasoning. A key limitation of this approach is the need to construct a rule base using expert knowledge, as well as the ambiguity in selecting appropriate membership function shapes. To address these challenges, various optimization algorithms have been developed. One such method is genetic programming, which purpose is to evolve a rule base capable of accurately capturing underlying patterns for correct classification while preserving interpretability through structural adaptation. This article explores the theoretical framework of self-configuring genetic programming combined with differential evolution for constructing fuzzy logic rule bases. It also presents their practical implementation and application to classification tasks.
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Improvement of the construction technique of substitution blocks for symmetric encryption algorithms
Статья научная
As it is known, block symmetric encryption algorithms are widely used to ensure information confidentiality. The resistance of encryption algorithms to the most common types of cryptanalysis is determined the quality of the blocks of substitutions. In the present work, the development of a methodology for constructing substitution blocks is being continued. In the first approach, Boolean functions with given cryptographic properties are used as component functions of substitution blocks. Previously, one of the authors proposed a reasonable methodology for the phased selection of Boolean functions for construction block. In this paper, in addition to such cryptographic properties of Boolean functions, such as: balance, possessing a strict avalanche effect, possessing correlation immunity, for the first time the nonlinearity distances of the first and second orders of Boolean functions are considered simultaneously. A study of the full set of Boolean functions of four variables was conducted. The result of it is the optimal set of Boolean functions for building substitution blocks when encrypted with the GOST 28147-89 algorithm. In the second approach, the substitution block are determined by an irreducible polynomial over the Galois field, such a scheme, used in the Rijndael encryption algorithm, is considered to be strong. The growth of calculating power of the computer necessitates an increase of the cryptographic strength of encryption algorithms. The authors have proposed substitution blocks for each round of the Rijndael scheme, based on different irreducible polynomials. A study of compositions representing a different combination of specially selected irreducible polynomials for ten rounds was carried out and the optimal set of polynomials with the best values of the encryption quality indicators by the Rijndael scheme was obtained.
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Increasing software reliability of a distributed control systems
Статья научная
The article considers a method of assessing and improving main parameters of the computer network efficiency. Reliability is the main criteria for ensuring the required performance of distributed control systems. To improve reliability of the computer network hardware and software redundancy are used. Software redundancy requires new versions to be developed for software modules in which failures are likely to occur. The article considers the N-version programming and recovery block as methods of introducing software redundancy and, taking the need to develop multiple versions of the same software module into account, estimates the costs of network software development. To implement the proposed approach article presents mathematical reliability model that takes into consideration the architecture of a computer network software and the labor costs that its development is going to require. This model becomes a basis for a software created to research computer network software reliability, which allows finding the dependence of network software reliability on the number of one of its software module versions. Comparison of the dynamics changes of reliability indicators and labor intensity of software development indicated a sufficient amount of software module versions that need to be developed. The article concludes by pointing out the importance of determining the labor intensity of network software development and of its usage in the design of a computer networks in which reliability is increased through software redundancy.
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