Статьи журнала - Сибирский аэрокосмический журнал
Все статьи: 3183
Статья научная
Currently the most significant state mission is an innovative development of Russian aerospace industry as the foundation for a new economic paradigm based on high technologies. Realising the mission is possible if highly-qualified personnel are available, and they are ready for innovative transformations in the industry, that requires to apply new or significantly advanced methodologies in training university graduates to be the major part of the personnel at the enterprises of aerospace industry. Researchers in the field of theory and methodology of professional education propose different solutions for personnel training and employment issue, one of them is connected with the paradigm of competence approach. The authors’ analysis of domestic and foreign publications demonstrates that there is not enough focused research in the field of competence approach potential application to organise proficient students’ training. This results in the necessity to develop new teaching technologies meeting modern requirements to the level of graduates’ competence. The goal of the research is to identify organizational educational conditions of applying competence approach technologies to improve the quality of training graduates whose majors are “Innovation technologies” and “Control systems of flying vehicles”, while they are doing academic assignments in cooperation. To specify the rational conditions and spheres of cooperation we have analysed the requirements of Federal state educational standards of high education for bachelor training whose major is 222000 “Innovation technologies” and specialists in major of 161101 “Control systems of flying vehicles”. We have compared the main characteristics in professional activity according to the graduates’ training programmes: the spheres, objects, and types of professional activity, job assignments as well as the requirements to the graduates demonstrated by the set of common cultural and professional competences. We have indicated their similarities and differences. According to the obtained results of the comparative analysis and the competence approach we consider the possibility to train students of “Innovation technologies” together with technical students applying interdisciplinary, inter-field specific education interaction. We prove the necessity to develop the interaction to increase the quality of teaching common cultural and professional competences to the students. We show the results of practical using the proposed approach on the example of training students with majors at the departments “Organisation and Management of High-Technology Enterprises” and “Systems of Automatic Control”.
Бесплатно
Статья научная
During stress measurements by hydraulic fracturing, fractures are opened and induced in the near borehole stress field as a result of the inflation of a straddle-packer Such very small events are surprisingly enough information along with televiewer measurements of the packer position to determine the in situ pore pressure. It is described the theory that goes along with the new procedure, the developed evaluation scheme leading to results for the geothermal reservoir in Bad Urach as well as the equipment designed for this unique field test.
Бесплатно
Increase of data transmisson efficiency in aircraft satellite monitoring
Статья научная
Satellite systems are one of the most common methods of tracking various objects around the world. There are vari- ous types of satellite systems for different purposes, but their common feature is data transmission by radio signal. The atmosphere of our planet is nonuniform and its every layer has some characteristics which impede data transmission. In case of insufficient power supply the transmission is practically impossible. That is why there should be worked out special methods and algorithms able to mitigate the atmospheric effect on the signals of the aircraft monitoring devices. The ionosphere, in particular, is the main cause of errors in determining the object’s location. For “Iridium” satellites that receive signals from “Iridium 9602” module at frequency of 1616-1625.5 MHz the ionosphere influence induces the alteration of the signal power due to the inhomogeneity of charged particles. The article presents the calculation of attitude data transmission loss in space as they are transmitted by “Iridium 9602” transceiver up to heights of 450, 500 and 600 km. The proposed method is based on modeling the current map of the total electronic content of the ionosphere. On the basis of this model, a correction of determining the monitored object’s location can be made. Today there are several centers performing calculation of total electronic content of the ionosphere. The calculation results are in free access. Thus, having the initial data obtained from the maps of the total electronic content of the ionosphere and the algorithm for making corrections, it is possible to correct the data while solving navigation problems. In particular, the GEMTEC model can be used, as its source of data is a map of total electronic content of the atmosphere.
Бесплатно
Статья научная
The paper presents the results of the introduction of a coding system for violations of technological discipline in the organization by making a statistical analysis of violations. Compliance with technological discipline is a necessary condition and basis for ensuring the required quality of manufactured products. Breaking the discipline leads to the production of defective goods, to a decrease in product quality, to deterioration of working conditions, and to accidents and breakdowns of technological equipment. In this paper, we present the procedure for analyzing recurring violations based on the collected data from 12 production departments of one organization. For the implementation of the coding system the authors collected, processed and analyzed data using statistical methods such as a checklist, a histogram, a Pareto chart, a diagram of the causes and results. The use of statistical methods does not require large expenditures and makes it possible to judge the state of the phenomena (objects, processes) with a given degree of accuracy and reliability. An important feature of the application of the presented methodology is the ability to predict and regulate problems at all stages of the product life cycle and, on the basis of this, to develop optimal management decisions. Sta- tistical methods are effective tools for collecting and interpreting data, as well as analyzing quality information. Coding violations of technological discipline makes it possible to identify recurring violations, develop corrective and preventive actions, both at the level of the production department and at the level of the organization as a whole. The results obtained are of considerable interest and can be used both at enterprises of space industry and at other engineering enterprises.
Бесплатно
Статья научная
In the process of launching a liquid rocket engine (LRE) and on the modes of its deep throttling of thrust, the prob- lem of balance of axial forces in the turbo-pump assembly (TPA) is the most important. The reason is the pumps and turbine work of the engine in non-nominal modes, and, consequently, the appearance of unbalanced excess of axial forces acting on the bearings of TPA. To reduce the axial loads in the TPA, an automatic discharge device (ADD) is used, the task of which is to reduce the axial impact on the bearings due to the action of hydrodynamic forces. In the process of working in the ADD, friction of the surfaces, which forms a hydraulic gap, is not allowed, otherwise it can lead to the local combustion. The object of influence is LRE RD-120 developed by “NPO Energomash named after academician V. P. Glushko” [1], working on liquid oxygen-kerosene components, with afterburning of the oxidizing gas-generating gas scheme. The pneumatic-hydraulic scheme of the engine, the TPA design, the working principle of automatic discharge device are presented. Using the example of the LRE RD-120, the effect of axial forces acting on the angular contact ball bear- ing located on the side of the turbine TPA is considered. When the engine was developed, it was established that under some launch conditions it is possible to contact sur- faces in the discharge device. In the article authors identify the conditions of contact in ADD and try to study the effect of the launch parameters of the LRE on the gap size of the working surfaces in the discharge device. For the theoretical analysis of the problem, a dynamic mathematical model of a liquid rocket engine is used. Mathematical modeling of engine start-up with nominal and early entry into operation of the combustion chamber was studied. The results show that with early starts of combustion chamber, there is a significant temperature rise in the gas generator, which can lead to the ignition of the nozzle or blades of the TPA turbine. Modeling the launch of the LRE with a change in the closing pressure of the oxidant supply valve to the pre-pump turbine booster, shows that this provides a longer operation of the oxidizer pump with a reduced hydraulic head, and allows changing the balance of axial forces during the engine launch and, as a result, prevent the full closure of the working gap in the ADD.
Бесплатно
Influence of plasma jets of electric jet engines on spacecraft functional characteristics
Статья научная
The issues of compatibility of correcting electric jet engines (EJE) and large-size transformable antennas (LTA) used in high-orbit communication satellites are considered. The paper deals with the erosive and polluting effect of EJE jets interacting with knitted mesh material (grid mesh), which is used for manufacturing LTA reflectors. The erosive effect of the EJE jets on the LTA mesh is characterized by the fact that the angles of ions incidence on the surface of the threads in the mesh are in the range from 0 to 90°, i. e. such effect takes place at practically any angle of ions incidence on the mesh surface. The research includes both mathematical description of physical processes and conducting a wide series of experiments, which makes it possible to achieve the necessary reliability of the results. It has been established that the effect of plasma jets of correcting engines can lead to significant sputtering of the reflecting coating from the surface of a large-size antenna reflector. The authors obtained experimental data on the degradation of the reflection coefficient of electromagnetic radiation from the mesh, depending on the degree of plasma jet influence. It was found that the sputtering of reflecting coating from the surface of threads does not significantly affect the reflection coefficient. The sputtering of the coating at the points of threads contact is much more significant. Strong dependence of the reflection coefficient on the type of mesh weaving was also found. The mechanism of sputtering products deposition on reflecting coatings of the thermal control system radiators was investigated. The results of calculations of the sputtering coefficient and the sputtering indicatrix of the reflecting coating applied to the mesh threads were obtained. The degradation of the functional characteristics of thermoregulatory coatings (TRC) during the deposition of thin films of gold, which is one of the possible materials for a reflecting coating, was experimentally determined. Estimates of the maximum permissible level of TRC contamination were obtained. It is shown that, subject to the relevant design rules, it is possible to use EJE and LTA together in high-orbit communication satellites.
Бесплатно
Статья научная
In this work, the effect of ZrO 2 nanoparticles prepared in a low-pressure arc discharge plasma on magnetic flux pinning of granular YBa 2Cu 3O 7-y/nanoZrO 2 composites has been studied. It has been shown that the ZrO 2 nanoparticles do not change the superconducting transition and the microstructure of superconductors. At a temperature of 5 K, the addition of 0.5 and 1 wt % of ZrO 2 nanoparticles may lead to the additional effect of magnetic flux pinning and the increase in the critical current density J c. The J c value for composites with 1 wt % is two times larger than that for the reference sample. The fishtail effect is observed for YBa 2Cu 3O 7-y/nanoZrO 2 composites at the temperatures of 20 and 50 K. The problems associated with the additional effect of magnetic flux pinning of granular YBa 2Cu 3O 7-y/nanoZrO 2 composites and the appearance of the fishtail effect have been discussed.
Бесплатно
Статья научная
The modern solar arrays for the most spacecrafts consists of solar cells which are formed by the thirty nano- and micro-dimensional epitaxial layers based on AIIIBV materials forming triple junction InGaP / InGaAs / Ge. This article presents the results of a study of experimental samples of thin single-crystal epitaxial InxGa1-xP layers with different indium and gallium concentrations (x = 38 to 53 %) that were grown on Ge - substrate by MOCVD industrial equip- ment. The theme of present investigation is the influence of epitaxial growth parameters on the crystal structure charac- teristics. The ratio of the components of the third group in the gas phase were calculated from the specified technological parameters. The rocking curves obtained by high-resolution two-crystal X-ray diffractometry were investigated. The lattice parameter and the ratio of indium to gallium in the solid phase were calculated. A high perfection of a single- crystal structure with an insignificant broadening of the X-ray diffraction peaks was observed in the range from 45 to 53 %. It is shown that the broadening of the diffraction peak of the structure can be the criterion of estimation of the quality of the grown structure in addition to the mismatch of diffraction maximum. Also the In / (In + Ga) ratio in the solid phase was calculated using the method of photoluminescence effect measuring. It was shown in comparison of data of x-ray diffraction with photoluminescence method the composition determination by photoluminescence method should be considered only as estimated.
Бесплатно
Information processing using intelligent algorithms by solving WCCI 2010 tasks
Статья научная
The article focused on the urgent problem of selection of strategies to deal with ill-structured problems involving the processing of both quantitative and qualitative data, high dimensionality and omissions in the data. This article provides a detailed analysis of the prediction models for data processing. Experiments confirm the effectiveness of intelligent algorithms, developed by the authors.
Бесплатно
Information search module based on multilinguistic thesauruses
Статья обзорная
The paper is devoted to the module for search, ranking and determination of document relevance by means of meta-search multilinguistic algorithms of data processing.
Бесплатно
Information training technology: learner’s memory state model
Статья научная
This paper mainly studies the foreign language training problem concerned with the application of the learner's memory state model in the informational-training technology. One of the approaches to intellectual technologies synthesis in training, developing new methods of training, proposed by professor L. A. Rastrigin was used. An exponential dependency of ignorance probability of a lexical unit upon the forgetting rate and time was taken as a trainer model.
Бесплатно
Innovative potential as the basis of defence industry complex enterprises competitiveness
Статья научная
In this article the formation mechanism and development factors of innovative potential of defence industry complex enterprises are considered as bases of their competitiveness in the conditions of economy transformation.
Бесплатно
Статья научная
The article investigates the essence and the priority of economy reindustrialization in Siberia taking into accounts the needs and characteristics of the innovation development of raw materials regions. The issue of developing the theoretical approaches to the formation of innovative regional development strategy is in the foreground, taking into account technological modernization priorities in Siberia. The aim of the given work is to determine the role of the rocket and space industry in the sectoral structure of Siberian regions as an essential component of the military-industrial complex (MIC) that is traditionally prioritized and has the potential for industrial growth to diversify the economy. We have analyzed the major milestones, the role and the problems of the defense industry in the USSR and the situation in modern Russia. Moreover, we have defined the role of the rocket and space industry in the MIC structure and engineering in the domestic economy, highlighted problems and development targets. Methodological basis of research and preparation of this work involves the fundamental researches of Russian and foreign scientists in the field of regional economy, innovation development and economic theory. The article gives the analysis of the reindustrialization experience in Japan and in other countries. It presents the definition of innovative development and innovation in the context of the key role of technological core of the regional systems development. Besides, the work describes the essence and direction of the economy diversification in the reindustrialization process of Siberia and a number of important aspects and problems of smoothing intraregional social and economic differences with diversification opportunities. The article presents the investment indices in technological innovation and modernization initiatives in major industries of Krasnoyarsk region, as well as the comparative evaluation with other regions of the Siberian Federal District (SFD). The analysis defines the role of the defense industry sectors in the innovative economy development of Siberia and their influence on the processes of new industrialization in other branches. In addition our task was to determine the priorities and challenges of innovative development and the economy diversification in Siberia, the main directions of the administration activities. That allows to solve the problems of regional innovative development and the industry modernization.
Бесплатно
Integration between higher school and industry in region as the factor of its innovative development
Статья научная
In this article the problems of Integration between Higher School and Industry in innovative development of region are covered. Retrospective analyze of co-evolution between defensive-industrial complex and Higher School in the face of Siberian State Aerospace University is carried out for estimation of dynamic interaction.
Бесплатно
Статья научная
Self-configuring genetic programming algorithm with the modified uniform crossover operator, that realizes a selective pressure on the recombination stage, is used for the automated integration of the computational intelligence technique ensembles. Ensemble members are the symbolic regression formulas, the artificial neural networks or their combination. They are also designed automatically with the self-configuring genetic programming algorithm. The comparative analysis of the approach performance is given on the benchmark and real world problems.
Бесплатно
Intelligent information technologies in time series forecasting
Статья
Intelligent information technologies enable to solve complex data mining problems in various domains of human activity. In this paper such popular techniques as artificial neural networks, fuzzy rule based systems and neuro-fuzzy systems are considered. A genetic programming algorithm is used for building intelligent systems ensembles in order to improve the performance and reliability of decision making. The methods proposed are applied to time series prediction task. The results obtained are compared to other state-of-the-art time series forecasting techniques.
Бесплатно
Inter-satellite optical communication link
Статья научная
A two-level system of data transmission in the optical range is considered between a low-orbit spacecraft located in a sun-synchronous orbit and a repeater satellite located in a geostationary orbit. This topic is rather relevant due to the fact that the rapid development of remote sensing satellites resulted in the increase of the amount of transmitted infor- mation, which in consequence introduced new requirements for communication systems. The increase of data transmission rate and severization of requirements for communication systems contributed to the development of one of the most promising areas of space communications, based on the information transmission via a laser channel, due to a high energy concentration and a much higher carrier frequency. The prospects for the application of optical communication systems are designated by lower power consumption, dimensional specifications and the mass of the transceiver equipment of the optical range (compared to radiofrequency range systems). The article describes the solution of application of optical communication link between a low-orbit spacecraft and a repeater satellite. The main factors that contribute to the attenuation in the process of signal propagation along the route are presented and analyzed. A model of a communication channel between a low-orbit spacecraft and a repeater satellite is provided for a visual image. Two different approaches of mutual guidance and tracking of laser terminals are described for using beacons and without ones. EDRS foreign system is considered as an analogue. The estimation of the main parameters of the communication link is given. The communication system considered in the article will allow for greater carrier capacity of the data transmission in the optical range between the low-orbit spacecraft and repeater satellite. The application of this system will allow solving problems, including in the interests of any departments and structures of the Ministry of Defense of the Russian Federation, for which the rate of obtaining information is one of the basic requirements for a satellite communication system. The tasks of precise targeting of receiving and transmitting devices arising as a result of narrow beam patterns can be solved with current technical means.
Бесплатно
Interaction of magnetic and dielectric subsystes in a bismuth nodymic ferrite-granate
Статья научная
Bismuth-substituted ferrite garnets possess magneto-optical (MO) properties and are used as spatial light modula- tors and indicators. The paper studies the influence of magnetic and electric fields on the structural characteristics of thin epitaxial films of bismuth-neodymium ferrite garnet (Bi: NIG) deposited on glass and gallium gadolinium garnet (GGG) substrates. Dynamic properties of polarization, relaxation in a magnetic and electric field are considered, which is an important task for getting a deep insight into the mechanisms of electromagnetic phenomena in solids. Dependence of the magnetostriction coefficient on the magnetic field and dependence of a relative change in the length of the film on the electric field at different temperatures are obtained. A change in the sign of magnetostriction constants with respect to temperature was found. The electric polarization in a periodically applied electric field of 400 V / cm with a frequency of 10 MHz is determined for various magnetic field orientations of 12 kOe and in the absence of a magnetic field. Anisotropy of polarization in a magnetic field and a functional dependence of the polariza- tion relaxation on time are found. These materials can be used as sensors of the magnetic field in a spacecraft.
Бесплатно
Статья
Automatically deriving the quality of a Spoken Dialogue System is an important task for both assessing dialogue systems and improving them. Work on automatic quality estimation for each system-user-exchange further holds the opportunity of using this quality information for online-adaption of the dialogues. The Interaction Quality paradigm is the first metric holding those features. Hence, this contribution gives an overview over the Interaction Quality paradigm and reviews recent estimation approaches. Furthermore, it renders drawbacks of the current approaches and proposes further directions in order to improve the estimation accuracy.
Бесплатно
Internal marketing as the tool of effectiveness increase of intellectual employee use
Статья научная
Under conditions of postindustrial economics intellectual employees as the main manufacturers and knowledge carriers are the source of long-term competitive advantage which is difficult to copy. Therefore the success of business demands the marketing approach not only to consume service, but also to home market that is employees. The article is devoted to the analysis of possibilities, specifying the internal marketing tools and the principles to increase efficiency of intellectual employees’ usage in the organization taking into account features of this human resources group.
Бесплатно
