Статьи журнала - Сибирский аэрокосмический журнал
Все статьи: 3183
The analysis of general tendencies of the foreign trade cooperation between Russia and China
Статья научная
The foreign trade cooperation between Russia and China in the system of market economy are considered. The offers for the foreign trade cooperation with purpose to increase the efficiency of a two side advantageous relations are resulted.
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Статья обзорная
In the article analysis of the professional-qualified structure and the market of educational services is given. The perspective directions of the training of qualified specialists for the innovative development of Krasnoyarsk region are defined.
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Статья научная
Currently, composite overwrapped pressure vessels (COPV), with high weight efficiency, are widely used in spacecraft (SC). In satellite construction COPVs provide necessary volume of working fluid for the realization of a highly efficient scheme of raising SC into geostationary orbit using standard electric propulsion engines. The issue of using such vessels in order to increase the period of active lifetime of SC and the implementation of deep-space exploration programs is relevant as well. The urgent task is to ensure the reliability of COPVs. The study of foreign literature suggests that fastening elements in direct contact with the vessel, have an important impact on the strain-stress behavior (SSB) of the vessel. The paper discusses the basic methods of fastening large-sized COPVs having a spherical shape - an adapter module is made in the form of a “skirt” and a cable-stayed system. We have created a finite element model (FEM) of COPV to analyze the effect of fastening elements on SSB of COPV. The analysis of the obtained results of the calculation shows that a cable-stayed system has almost no effect on SSB of COPV, in contrast to a composite “skirt”, which reduces the effective stresses in the place of attachment to the vessel by two times or more, causing uneven distribution of stresses. The composite “skirt” directly transfers its buckling mode to the vessel, which reflects the significant effect of the “skirt” on the vessel’s SSB. The use of a composite “skirt” in comparison with a cable-stayed system has high probability of COPV failure. The obtained results show that a cable-stayed system is more effective way to fasten COPV than a composite “skirt”.
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Статья научная
The tendencies of the foreign trade cooperation between Krasnoyarsk region and China in the system of market economy are considered. The offers for the foreign trade cooperation with purpose to increase the efficiency of two side advantageous relations are resulted.
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The application of image enhancement method for face recognition systems
Статья научная
Three-step face recognition algorithm which includes non-linear enhancement (dynamic range compression) and faces localization on the basis of skin color segmentation with subsequent extraction of anthropometric face points is proposed. The process of face recognition on the basis of principal component analysis is also considered.
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Статья научная
The paper considers the issue of restoring the level of the telemetry signal carrier frequency at digital processing in the automatic carrier control tract and the calculation of the threshold for taking the decision about the validity of received information symbol from the spacecraft and carrier rocket. We have described the applied method and algorithm for calculating the level of the carrier frequency and the level of threshold for making a solution based on histogram processing of the signal from the output of the frequency detector.
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The assessment of high pressure pipelines of thermal power stations by non-destructive methods
Статья обзорная
The method of the monitoring of the thermal stations high pressure pipeline is described.
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The asymptotic probabilistic genetic algorithm
Статья научная
This paper proposes the modification of probabilistic genetic algorithm, which uses genetic operators, not affecting the particular solutions, but the probabilities distribution of solution vector's components. This paper also compares the reliability and efficiency of the base algorithm and proposed modification using the set of test optimization problems and bank loan portfolio problem.
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The automation process procedures of the subsystems block verification for space vehicles management
Статья научная
Described are the automation procedures for the software of logic verification in subsystem of the management perspective space vehicle block functioning. The achieved results by the implementation of these procedures are presented.
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The definite questions of simulation of transformable space structures dynamics
Статья научная
This paper describes large transformable space structures with various configuration in the folded transport posi- tion and in the open working one. As an example, simulation of transformable space structures dynamics is shown for the antenna circuit foldable load-bearing frame with diameter of 5 m. For investigation of the foldable frame deploy- ment dynamics, a design scheme presented by a system of rigid bodies connected with each other by hinges is accepted as it is simple, but at the same time it considers features of the structure well enough. For performing stress analysis of the foldable frame elements during deployment, the frame shape at the certain time point of deployment, when relative velocities of adjacent elements are ultimate, is chosen. As a results of calculation using MSC.Adams software, positions, velocities and accelerations of the centres of mass of the foldable frame elements as well as the angular velocities and accelerations of the elements for each time step of the deployment are obtained. To perform stress analysis of the fold- able load-bearing frame, finite element model of the frame is developed using MSC.Patran/Nastran software. As a re- sults of investigation of stressed and deformed states of antenna circuit foldable frame elements both without taking into account damping and with consideration of damping, stresses arising in the foldable frame elements at the certain time points during deployment are found.
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Статья научная
The analysis of conditions to provide durability, reliability and the transports effectiveness of the civil aircrafts is performed.
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Статья научная
In practice problems, which consist in the search of the best (optimal) solution according to the different irredundant and contradictory (conflicting) criteria, called multi-objective problems, are of frequent occurrence. One of the most commonly used methods for solving this kind of problems consists in combination of all criteria into the single one by using some linear relation. However, despite the simplicity of this method, solving problems with its help may cause other problems related to the determination of the mentioned linear combination, namely related to the determination of the weight coefficients for each criterion. The incorrect selection of these coefficients may lead to non-optimal solutions (according to the Pareto theory). In this regard, recently various population-based algorithms have been proposed for solving the described problems, which are the modifications of these population-based algorithms for solving single- objective optimization problems. This article describes the developed modifications of the Differential Evolution algorithm (DE) for solving multi-objective unconstrained optimization problems based on the well-known NSGA (Nondominated Sorting Genetic Algorithm) and MOEA/D (Multiobjective Evolutionary Algorithm Based on Decomposition) schemes, which use the Pareto theory. The investigation into the efficiency of the Differential Evolution algorithm for solving multi-objective optimization problems in relation to the chosen mutation operator of the original DE algorithm and to the multi-objective scheme was conducted. The developed modifications were tested by using some well-known multi-objective real-valued optimization problems with 30 variables, such as ZDT1, ZDT2, ZDT3, etc. The practical problem of spacecraft control contour variant choice was solved as well. The experimental results show that better results were achieved by the Differential Evolution algorithm with the simplest mutation operators combined with the NSGA scheme. Thus, the applicability of the described modification for solving practical multi-objective optimization problems was demonstrated.
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The evaluation of the quality management system effectiveness at machine-building enterprises
Статья научная
In this article we propose a method of evaluating the quality management system effectiveness. The major criteria of the evaluation are formulated, using the Joint Stock Company Krasnoyarsk Refrigerator Plant “Biryusa” as an example.
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The fast algorithm of intermediate perspectives reconstruction on a stereopair
Статья научная
Here we have considered the effective A. A. Lukianitsa algorithm of stereo-reconstruction. We have offered a modification of the particular algorithm, which allows increase in the speed of the algorithm functioning. We have also presented the results of the conducted experiments.
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The formation of the enterprises investment appeal
Статья научная
The article concerns the problem of investment appeal compounds, approaches to its value. There are groups of actions which can help to raise the investment appeal of the enterprises.
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Статья научная
The influence of the conditions for passing GLONASS and GPS satellite radio navigation signals on the errors of defining relative coordinates is studied.
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Статья научная
The correlation between the size of a positive mobile charge and electronic conductivity of oxide on polycrystalline silicon is established with the help of experimental method of thermally stimulated polarization and depolarization of MIS-structures. The boundary conditions of a problem for the working model of behavior of a mobile charge in isolating layers generated on a rough semiconductor film are formulated.
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Статья научная
At present to transfer a spacecraft from a low earth to geostationary orbits propulsion systems of two types are most widely used: chemical and electric. Each type has its advantages and disadvantages. The application of any one of them does not always satisfy conflicting requirements. A possible solution may be the use of a combined propulsion system consisting of a chemical and electric propulsion system. This combination allows the spacecraft to be launched faster than using only electric motors, and it is more efficient in terms of the payload mass than using only a chemical propul- sion system. Electric propulsion engines (plasma or ionic) need energy sources. Usually, solar batteries are used for these purposes. The idea of using such a combined propulsion system, consisting of a solar electric propulsion sys- tem and the Fregat upper stage, was considered within the “Dvina TM” research project. The use of such a propulsion system requires, even at the design stage, to determine the parameters of the various types of engines that make up its structure. For a reasonable choice it is necessary to have information about the influence of the various propulsion system parameters on the final characteristics of the maneuver. When putting a spacecraft into orbit, it is necessary for the spacecraft to overcome Van Allen belts while the ele- ments of its design are subjected to intensive action of charged particles, which can significantly limit the period of ac- tive existence. Using a combined propulsion system, it is possible to shorten the time of being in a field of high radiation level significantly. The aim of the study was to synthesize a method for estimating the effect of the combined propulsion system parame- ters on the integral dose of radiation accumulated during the maneuver, when putting a spacecraft into a geostationary orbit. Different variations of the combined propulsion system application (thrust variations) allow to optimize the maneuver of the spacecraft and to reduce the integral dose of radiation. As a result of the work, a method was proposed to evaluate the influence of the parameters of the combined propul- sion system taking into account the passage of the Earth radiation belts, the program was implemented, calculations were made and the results were analyzed.
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The mechanism of stimulation of development of biotechnologies in foreign countries
Статья научная
The biotechnology is one of scientifically-practical priorities of the XXI century. The key role in stimulation of development of biotechnology in foreign countries is taken up by the state which solves this problem by means of a complex of measures both administrative, and economic influence.
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The method of automated development of an assembly drawing of a cable network
Статья научная
The final stage of designing a cable network of spacecraft (as well as any other product) is the release of design and operational documentation. The automation of this process allows to improve the quality of documentation and de- crease the manufacturing time of spacecraft. The JSC ”Information Satellite Systems” (ISS) uses its own integrated software complex ”ALCAB” for releasing design documentation package for a cable network. For the assembly drawing development, the company uses CAD without integration with ”ALCAB”. In this regard, adding or removing items in the specification leads to the further refinement of the drawing. We propose the technique of solving a problem connected to the automation of the assembly drawing development for a cable network produced on a plane. The main task is to create associative link between the specification items and the cable network drawing. In this article we present the results of the analysis of the structure of the cable network 3D model designed in ”CATIA V5” CAD. There are schematic examples of harness topologies. The analysis identified the list of data to be extracted from the 3D model. We described the most interesting tools of ”CATIA V5” CAD that allow you to automate many processes including the development of your own software solutions. The analysis identified the tools for automated uploading of all re- quired data from the model. The examples of these tools are ”Knowledge Expert” and external programming environ- ment ”CAA RADE”. The analysis of their performance showed that the extraction of data using an algorithm developed with ”CAA RADE” was faster than using ”Knowledge Expert”. We described the potential of drawing tools in ”CATIA V5” CAD such as ”Electrical Harness Flattening” and ”Drafting” that allow you to automate the assembly drawing development. The paper proposes the method of automating he assembly drawing development of a cable network developed with the use of three-dimensional technology using the tools of ”CATIA V5” CAD and software designed at the JSC ”ISS”.
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