Математика, механика, информатика. Рубрика в журнале - Сибирский аэрокосмический журнал
The modeling of the world socio-economic strategy as an optimal control problem
Статья научная
An approach to the modeling strategy of global social-economical development on the basis of the economic-mathematical optimum control model, considering interaction of the basic economic agents of the world social-economic system (WSES) - industrial, consumer, financial sectors, as well as the operating center (the world government) is described in this article. The task of optimizing the global social-economic development is formulated; the main principles of the analysis, restrictions and target criteria are analyzed.
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Статья научная
The invariant system of information processing based on obtaining of the rectangular envelope by using a synchronous detector is considered. The indexes of the noise immunity of such system are calculated. It is supposed that the closest readings of the rectangular envelope are interfered with the additive noise whose readings are weakly correlated with each other. The quantitative estimation of the operation of such system is compared with the quantitative indexes of the known invariant system under non-correlativity of the noise readings.
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Статья научная
An algorithm of right-hand side and Jacobian formation of differential equations of chemical kinetics is described. Numerical simulation of the cesium cycle in the upper atmosphere is conducted by means of the L-stable method of the second order of accuracy with the control accuracy. The results of the computation are presented.
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The possibilities for optimizing the functional system structure of civil aviation aircraft
Статья научная
This is an analysis of the traditional approach to systems with individual reserving reliability calculation usage. An alternative calculation method for these systems with an individual reserve system has been developed. Its application is demonstrated.
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Статья научная
In this article we have considered the possibilities of realizing diversity reception algorithms in hybrid fibers of wireless information transfer. At the heart of diverse reception algorithms lies the fact that when solving problems of optimal field processing, their correlation curves are definite for the description of the Gauss and any kind of stochastic fields.
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The research of Raman spectra in CoxMn1-x solid solutions
Статья научная
Temperature dependence of Raman spectra in the frequency interval 100... 1 200 cm1 in the 100...300 K range temperature has been investigated in the substance of CoxMn1-xS solid solutions. A Raman spectra study has uncovered evidence of strong orbital fluctuations that manifest itself in kind of composite line shape at ω2 273...298 cm-1, arisen from splitting of phonon modes with different temperature dependences of the intensity below the orbital ordering transition.
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The system of software-driven verification of network IP-cores in a reference system-on-chip
Статья научная
The article presents the application of network Intellectual Property cores (IP cores) software-driven verification method for network infrastructure devices in the system-on-chip microprocessor (SoC) used as verification environ- ment. The SoC used for verification is a reference system since it consists of previously fully verified and approved IP cores which interact in this system correctly and accurately. Software of a reference system generates test inputs and processes responses to them which are received from a verified device. Conclusions of executed or unexecuted tests are generated on the basis of the expected results. A set of expected results of input action is a reference model of a verified IP core. General architecture of a verification system of a network device IP core has a form of a classic test loop. The vari- ants of verification architecture given depend on the type of a verified network device: an individual network codec, a network protocol controller or a network switch. The presented architectures show the simplicity of software-driven verification. The test environment naturally results from the reference SoC model and test software developed in such high-level programming language as C/C++. When the software-driven verification of an IP core takes place in reference SoC environment, the test software con- sists of two types of tests: directed tests and restricted-random tests. Successive use of both the given types of tests and typical scenarios of network devices interaction which include request-reply packages transmission between network nodes provides high coverage of a verified IP core with test situations. To check fault tolerance function it is supposed to use the scenarios of network devices interaction in conditions of possible faults made by predetermined introducing of errors into packages transmitted over the network connections. Program tests which are developed and proved during the IP core model verification are completely ready to be used in hardware SoC prototype including the given IP core in the programmable logic device. The presented approach to functional verification was used for IP cores testing in SpaceWire network infrastruc- ture: a fault tolerance codec, a RMAP protocol controller and a routing switch.
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To geostationary collocation problem
Статья научная
This article is about geostationary collocation problem which means problem of cooperative station retention. As part of this task it is assumed that different control centers don’t exchange information about kinematic parameter’s vectors and maneuvers. So there is full information and control possibility for one collocation member only. Sets of kinematic parameter vectors are available for the other collocation members. This situation corresponds to lack of a priority information conditions, so there is f nonparametric uncertainty situation because due to absence of informa- tion on parametric control law which is used to choose maneuvers for other collocation members. Modern collocation theory doesn’t allow to avoid collision and process station retention in this condition. Synthesis of nonparametric regu- lator is in contemplation to solve this problem. First task of this regulator is estimation of previous maneuvers by proces- sing kinematic parameter vectors sets. Second task is estimation of coordinates for every collocation member. Finally, nonparametric regulator must synthesize control which allows to process station retention and collocation. Suggested algorithm belongs to nonparametric class, so it is not necessary to know parametric form of controlling law. It is based on modification of Nadaraya-Watson nonparametric estimation. The geostationary movement model including main perturbations, and most common collocation approaches are suggested. Nonparametric control algorithm is proposed.
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To the problem of nonparametric robust estimation of the regression function on observations
Статья научная
There are parametric and nonparametric statistical models in the literature. These models differ from each other in levels of the prior indeterminacy in the statistical description of observations. The difference in ways these models were created tends to smoothing by introduction of transition models. It is explained by the fact that a statistical model, as well as any other model, is inevitable idealization and it can be only successful approximation of actual processes at its best. Emphasizing this fact, Box writes: “All models are irregular, but some of them are useful”. When using statistical procedures it is desirable to have information about what deviations have a decisive influ- ence on the final conclusion at statistical analysis. In case the true distribution is not normal, there can be questions of normal theory reference procedures applicability. The recent research approach called “robast statistics” and offered as “third generation statistics” after parametric and nonparametric statistics by American mathematician J. Tyyuki is devoted to answer formulated above questions and create statistical procedures insensitive to deviations from assump- tions. A number of publications on this approach constantly increases, there are already monographs, among them the first book of Hyubera, the book by F. Hampel and others, educational literature is also available. The “robust” term, which corresponds to the definition “rough, strong”, was introduced into statistical literature by Box in 1953 and since the middle of the sixtieth this term has became conventional for the section of statistics where statistical procedures insensitive to deviations from the accepted model assumptions develop. The robust idea has had a long history, which was described in Stigler’s work. It appears in the work of K. Gauss, S. Newcomb, A. Eddington and others. However systematic development of robust ideas began with J. Tyyuki’s works and, especially, after the work of Hyuber in 1964. In this work an estimation of functions with a data outlier problem is given. In case of nonparametric indeterminacy the following steps are used to solve the problem: 1) the type of regression function with input data is set; 2) function estimation is applied. We suggest the following reliable robust nonparametric estimation approach. The main idea is to exclude the data which can affect estimation.
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Статья научная
The article deals with the functional and algorithmic implementation of multi-version execution environment of modules as components of the onboard software of autonomous pilotless objects by means of real-time operating system. One of the approaches to implementation multi-version execution environment - implementation of the princi- ple of a pseudo-parallelism (imitation of concurrent execution of tasks by dividing the time of their execution) are given. Messaging process between multiple tasks implemented by cycloram, as the procedure of returning of voting result by queuing mechanism.
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Two-level genetic algorithm for X-ray powder diffraction structure analysis
Статья научная
A new evolutionary approach for crystal structure determination of powders based on X-ray diffraction full-profile analysis and genetic algorithm of global optimization is suggested. An investigation of efficiency of given algorithm is carried out on test real-world problems of structure determination.
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Статья научная
The article considers the content of the course of post graduate students’ training in a foreign language for scientific purposes in a technical university of aerospace profile. The experience of work in the context of SibSAU training of young scientists to effectively functioning in an international professional scientific community is analyzed. The experience of work in connection with the growing trend of writing scientific texts (articles, publications, monographs, etc.) in a foreign language (English) is presented. A complex structure of work with postgraduate students in teaching a foreign language for scientific purposes is developed and presented. Particular attention is paid to the integration of Internet resources in the process of preparing for the candidate's exam in a foreign language, and subsequent publications in international scientific systems such as Web of Science, Scopus. The article reflects the experience of testing and implementation of various Internet sources, presents the most effective ones. High cognitive professionally-oriented and didactic potential of the Internet technologies used is marked.Particular attention is paid to the scientific search systems, allowing a full-text search on articles of major foreign publishers’ magazines, articles in the archives of articles and preprints, scientific resources of Internet. Links for work with authentic scientific periodicals, modern dictionaries and encyclopedias are proposed. The article maybe of interest to postgraduate students of technical universities of aerospace profile, preparing for the successful functioning in the scientific community in order to accommodate their publications in leading peer-reviewed journals, as well as for foreign language teachers using in integrated methods in teaching a foreign language for scientific purposes.
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Статья научная
The article reveals new methods of effectiveness increase in teaching foreign languages to technical students using information and communication technologies and their practical implementation at the premises of the Foreign Languages Resource Center of Siberian State Aerospace University. Adoption of information and communication technologies to the educational process is based on students’ independent language learning that encourages more productive development of language competences mastered by students and future specialists in a special area of technical knowledge as a whole.
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Using genetic programming techniques for inertia-free system identification tasks
Статья научная
The problem of identification of inertia-free objects is being investigated. The overall pattern of the process investi- gated is being described. As a research object, a stochastic inertia-free process of modeling has been chosen. A feature of the process under consideration is the fact that unmanaged but controlled variables influence the process under investigation. In addition, the process under investigation is affected by unmanaged and uncontrolled variables. The levels of priori information has been briefly considered and characterized. For each level of priori information the identification method has been described. Particular attention is paid to the levels of priori information under which the identification task in a “broad” sense needs to be addressed. As a method of identification, genetic programming is considered. Method of genetic programming has been chosen as a research object since this method is more commonly used in the identification problem. Despite the frequency with which this method is used, it is interesting to look at the results of this method under different conditions. As changing conditions, the object’s complexity and the change in the volume of the training sample were used. For the identification process, objects with different structures were selected. The dependence of the time of finding the structure of the object on the size of the training sample was investigated. As shown by studies, there is no clear correlation between the time of finding the structure of the object and the size of the training sample. In addition, relationship between the time of the structure and the “complexity” of the object was investigated. As a criterion of “complexity” of the object, the number of input variables was taken. The study showed correlation between some values; with the increase in the number of input variables, the time of finding the structure of the process also increased.
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Verification of finite-element model spacecraft via test results
Статья научная
The question of ensuring strength, durability and survivability of a spacecraft construction with mathematical mod- eling complexes is a modern trend in satellites design. This approach is based on the shortening of the prelaunch preparation stage. In particular, this is due to the reduction in the number of vibration tests of a spacecraft (SC). In the present work, using the example of vibration tests of “Express-1000K” service system module, we consider the verifica- tion technique for the mathematical model of communication satellites, output by a pair of payloads. The choice of this research object was caused by the conceptual scheme for modern space vehicles constructing, based on the modular principle. The service system module is the basic supporting structure of the spacecraft, able to integrate with any pay- load (information support, scientific research, geodesy and remote sensing, navigation) and is a universal tool in a sat- ellite construction. In tests with harmonic vibration, the first longitudinal and transverse tone of the spacecraft oscilla- tions are well identified, which can be fairly easily predicted applying the finite-element model. Proceeding from this, the accuracy of forecasts depends, to a greater extent, on the complexity of the modeled construction and the modeling procedure being used. The study provides a finite-element modeling technique for spacecraft output by a pair of pay- loads; the dynamic characteristics of the object of investigation by calculation and experimental methods are obtained. The identification procedure was carried out using the ‘modal consent’ method. The verification technique considered in the study makes it possible to carry out effective adjustment of the finite-element model. The finite-element model obtained by verification results allows to effectively evaluate the behavior of a spacecraft already at the design stage, which enables to shorten the time of vibration tests. The main results of this research were applied in verification of mathematical models of modern spacecraft developed by JSC “ISS”. The importance of applying verification methods of the mathematical model of the product at the preliminary (design) stage of spacecraft creation was noted.
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Video based flame detection algorithm
Статья научная
Video based flame detection from a surveillance camera offers early warning to ensure prompt reaction to devastat- ing fire hazards. Many existing fire detection methods based on computer vision technology have achieved high detec- tion rates, but often with unacceptably high false-alarm rates. This paper presents an automatic flame detection method using computer vision and pattern recognition techniques. This method uses the features of fire, such as the moving parameters, chromatic components, and geometrical (flickering) features. For experimental researches the databases of Bilkent University and Dyntex database were used. The developed method of flame detection on video provides 89.5-98.2 % of accuracy for flame sequences. The number of frames of test video sequences was 6.853, the total duration of the videos is 5 minutes. Experimental results show that the proposed method is feasible and effective for video based flame detection.
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Автоматизация проектирования торцевых генераторов мощностью до 20 кВт
Статья научная
Приводятся основные принципы автоматизированного проектирования активной части низкоскоростного торцевого синхронного генератора для микроГЭС, обзор потребностей рынка в микроГЭС, шаги, предпринятые для ускорения процесса сборки, снижения стоимости изготовления. Используются методы объектноориентированного программирования, динамически подключаемые библиотеки. Результатом работы является программный комплекс «МикроГЭС Проектировщик», который позволяет создать модель в SolidWorks методами автоматизированного проектирования, где каждый параметр рассчитывается исходя из электромагнитной модели и конструктивных ограничений. Областью применения данного программного обеспечения является электроэнергетическое и гидротехническое строительство. Применение данного пакета позволяет сократить время проектирования конструкции микроГЭС, снижая цену изделия.
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Автоматизация процесса генерации компиляторов мультисинтаксических языков программирования
Статья научная
Разработанная программная система повышает эффективность поиска ошибок в отлаживаемых программах синтаксического анализа на основе существующих спецификаций Flex и BYacc.
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Статья научная
Рассмотрен синтез эволюционных алгоритмов решения задачи символьной регрессии и оптимизации. Предложены их модификации в рамках разработки интегрированной процедуры автоматизированного построения и оптимизации математических моделей сложных систем и процессов.
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Автоматизация формирования информационной базы мультилингвистической адаптивно-обучающей технологии
Статья научная
Рассмотрены системные аспекты формирования информационной базы мультилингвистической адаптивно-обучающей технологии, такие как сбор информации о скрытых лексических связях, и применение ее в формировании информационно-терминологического базиса. Предложена система первичной обработки текстов, приведен алгоритм ее работы, а также структура выходных данных.
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