Статьи журнала - Сибирский аэрокосмический журнал
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Forecasting of the leading indexes of social-economic factors on Yeniseisk district
Статья научная
In this article presents the forecast of social and economic factors influencing Yeniseisk district over 2009–2012. The main supposition of the forecast is following the existing linear trend of the main social-economic factorsdevelopment with permanence of external factors. This results in the positive track record of the growing investment in the fixed capital that is stipulated by involving large-scale investment projects.
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![Formation features of the central layers of the alloy Fe - 3 % Si (110)[HKL] rolling textures](/file/thumb/148321932/formation-features-of-the-central-layers-of-the-alloy-fe3-si-110-hkl.png "Formation features of the central layers of the alloy Fe - 3 % Si (110)[HKL] rolling textures")
Formation features of the central layers of the alloy Fe - 3 % Si (110)[HKL] rolling textures
Статья научная
The fields of solid-state physics, metallurgy, plastic deformation, mathematics and continuum mechanics are engaged in the studies of texturing of metals and alloys and their influence on the operational properties of products. As a rule, the most significant results are expected at the interface between these sciences. The technologies of obtaining textured materials by metal forming processes occupy a special place in the metalworking sphere. This is due to promising directions in technologies for producing semi-finished and final products with improved structure-sensitive properties, by regulating the texturing, taking into account initial crystallographic orientation of the workpiece. The first issue to note is the formation of an ideal, one-component crystallographic texture in anisotropic metallic materials. The second issue is to obtain semi-finished and final products with more specific service properties: crystallographic texture with specific predetermined components. For instance, due to the crystallographic texture, it is possible to increase the resistance of metals and alloys against corrosion and hostile environment. Considering textured materials as composite, we must note that directionally oriented crystallites with crystallographic direc- tions relative to the laboratory direction perform as reinforced elements. The initial texture in the processing plane is especially important. The materials, which possess unique structure-sensitive properties acquired through pressure treatment, are very promising for a widespread use in the sphere of aerospace technology. Obviously, the properties and means of their achievement are diverse and require setting a specific task. Therefore, further research in this sphere is especially promising. The article presents the research findings, considering the effect of initial crystallographic orientation and deformation modes on the rolling texture in the central layer of Fe - 3% Si (110)[ hkl ] single crystals. Several groups of single crystal samples underwent rolling under laboratory conditions. The groups of samples were classified according to the final deformation rate, the ideal crystallographic orientation of the rolling plane and deflections of the ideal orientation plane direction from the rolling direction. The methodology of the experiment took into account the compression rate value during one rolling. We analyzed the results of rolling, using the radiographic method. The next step was to superimpose the radiographic data on a stereographic projection and to construct straight pole figures. The results of straight pole figures decoding revealed differences in the texture formation from the previously obtained data. The research shows the manifestation of the one-component deformation texture in the central layer.
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Formation of regional wholesale food markets system
Статья научная
The management structure and the infrastructure of regional wholesale food market, the scheme of agricultural products and foodstuffs movement to the end-consumer are offered. The place of the wholesale market in the system of food supply is defined.
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GERT-анализ формирования технологических циклов управления космическими аппаратами
Статья научная
Предложено использовать аппарат сетевого анализа, включая GERT-анализ, для решения задач оптимизации формирования технологических циклов управления (ТЦУ).
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GERT-сетевой анализ производственных процессов
Статья научная
Для временного анализа производственных процессов предлагается их представление в виде стохастических GERT-моделей, что позволяет учесть неопределенность в продолжительности выполнения работ и альтернативность развития производственных процессов.
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GIS and satellite remote sensing for archeology: exploring polar history
Статья научная
The development of archeology in the second half of the twentieth century has received new impetus thanks to the emergence of a new tool - remote sensing, which began its development with the help of satellite technology. Images from space have allowed detecting archaeological sites, the location of which has not been possible to establish other ways. Initially, the new technology was advancing in the framework of state programs in different countries (USA, France, India, Russia and others.). Subsequently, a number of private geo-information services, such as Google Earth, Wikimapia, which significantly simplified access to the technology by all comers. Both small research teams and enthusiasts had the opportunity to use the services of satellite technology in their investigations. The downside of this technology can be used by looters and pseudoarcheologists. Modern geographic information systems have global reach, but different regions are of a different capacity. The northern territories of the Krasnoiarskii krai are reflected in open-access satellite imagery the resolution of which is not always sufficient enough to contribute to research. This results in the need for high-precision satellite imagery. Likewise, it is still necessary to perform field investigation to establish the concrete position of a historical site. This article discusses the use of open-access satellite imagery in studying a number of historical sites and objects (shipwrecks) related to the history of polar exploration on the lower Yenisei and the delta of this river.
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Generation of the state tree based on generative grammar over trees of strings
Статья научная
In the article the principle of state trees generation is considered based on the generative grammars over trees of strings in such objects as the sentences of natural languages, as well as two and tree dimensional images. The image of the object as a forest is considered; including the trees of object different layouts for the purpose of complex system modeling.
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Geo satellite attitude and orbit control: fixed orbit control thrasters
Статья научная
The paper describes the enhanced application ofhigh-economical electro-jet orbit control thrusters for geostationary satellites; in particular, generation of controlling moments to the benefit of satellite attitude determination and control subsystems in the course of orbit control maneuvers ongoing. The scheme with thrusters fixed on a satellite body is analyzed. Possible orbit control session procedures are proposed on the basis of controlling moments generation. Advantages and disadvantages of the proposed approach are analyzed.
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Graphic information processing using intelligent algorithms
Статья научная
Finding an appropriate set of features is an essential problem in the design of a shape recognition system. This paper attempts to show that for recognition of objects with high shape variability such as handwritten characters and human faces it is preferable to use the modified artificial neural network to feed the system with processed images by novel scale-and rotation-invariant interest point detectors and descriptors and to rely on learning to extract the right set of features. Experiments have confirmed the usefulness of the modified artificial neural network in a real-world application.
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Greedy heuristic method for location problems
Статья научная
Authors consider multi-source location problems, k-means, k-median and k-medoid. Such problems are popular models in logistics (optimal location of factories, warehouses, transportation hubs etc.) and cluster analysis, approximation theory, estimation theory, image recognition. Various distance metrics and gauges allow using these models for clustering various kinds of data: continuous and discrete numeric data, Boolean vectors, documents. Wide area of application of such problems leads to growing interest of researchers in Russia and worldwide. In this paper, the authors propose a new heuristic method for solving such problems which can be used as a standalone local search method (local search multi-start) or as the main part of a new algorithm based on ideas of the probability changing method. For the parameters self-tuning of such algorithm, the authors propose new meta-heuristic which allows using new algorithm without learning specific features of each solved problem. Algorithms were tested on various data sets of size up to 160000 data vectors from the UCI repository and real data of semiconductor devices examination. For testing purposes, various distance metrics were used. Computational experiments showed the high efficiency of new algorithms in comparison with local search methods used traditionally for the considered problems. In addition, results were compared with the evolutionary methods and a deterministic algorithm based on the Information Bottleneck Clustering method. Such comparison illustrated the ability of new algorithms to reach higher preciseness of the results in reasonable time.
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H-модели для безынерционных систем с запаздыванием
Статья научная
Рассматривается проблема моделирования нового класса процессов, имеющих «трубчатую» структуру в пространстве «входных-выходных» переменных. Модели процессов этого класса существенно отличаются от общепринятых параметрических моделей, представляющих собой поверхности в том же пространстве. Специально анализируется вопрос о моделировании многомерных систем при наличии малых объемов обучающих выборок. Для построения обучающихся параметрических моделей «трубчатых» процессов вводится соответствующий непараметрический индикатор. Приводится новый класс обучающихся параметрических моделей и некоторые результаты их численного исследования.
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Hardware implementation of the unit of the GNSS consumer
Статья научная
Navigational equipment is currently used to solve a variety of tasks, such as providing civil and special aviation, navigating, surveying and mapping, Internet devices and unmanned vehicles perfomance. The level of technological development of digital signal processing devices at first glance removes the need for deep study of computational algorithms, but this is only at first glance. As a result of expanding the scope of navigation tools, there is a need to increase the working channels, increase the dynamic range of the processed signals, and also improve the reconfiguration capabilities of signal processing devices. Any synthesized computational algorithm that can be described in hardware description languages, such as VHDL and Verilog, consists of summation operations and a shift operation of the register. There are several basic architectures of adders, each of which has the advantage of either speed of operation or simplicity of implementation. The development of computational architectures working at frequencies of 100 - 200 MHz requires pipeline calculations. Despite the fact that the pipeline architecture has large overheads for equalizing the delays of the computational blocks, its use is justified when processing and converting signals while solving the navigation task. The architecture of hardware computational blocks for constructing navigation equipment for the GLONASS / GPS consumer is considered in the article. The possible ways of increasing the efficiency of some architectures when implementing them on the basis of programmable gate arrays (FPGA) are given.
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Human-human task-oriented conversations corpus for interaction quality modeling
Статья научная
Speech is the main modality for human communication. It can tell a lot about its owner: their emotions, intelligence, age, psychological portrait and others properties. Such information can be useful in different fields: in call centres for improvement in the quality of service, in designing Spoken Dialogue Systems for better adaptation of a system to users' behaviour, in the automatization of some processes for analysing people's psychological state in a situation with a high level of responsibility, for example, in a space programme. One such characteristic is the Interaction Quality. The Interaction Quality is a quality metric, which is used in the field of Spoken Dialogue Systems to evaluate the quality of human-computer interaction. As well as in Spoken Dialogue Systems, the Interaction Quality can be applied for estimating the quality of human-human conversations. As with any investigation in the field of speech analytics, for modelling the Interaction Quality for human-human conversations a specific corpus of task-oriented dialogues is required. Although there is a large number of speech corpora, for some tasks, as, for example, for Interaction Quality modelling, it is still difficult to find appropriate specific corpora. That is why we decided to generate our own corpus based on dialogues between the customers and agents of one company. In this paper we describe the current state of this corpus. It contains 53 dialogues, corresponding to 1165 exchanges. It includes audio features, paralinguistic information and experts' labels. We plan to extend this corpus both in the feature set and in the observations.
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Статья научная
A fuzzy classifier is one of the intelligent information technologies allowing the generation of a fuzzy rule base suitable for interpretation by human experts. For a fuzzy classifier automated design the hybrid self-configuring evolutionary algorithm is proposed. The self-configuring genetic programming algorithm is suggested for the choice of effective fuzzy rule bases. For the tuning of linguistic variables the self-configuring genetic algorithm is used. A hybridization of self-configuring genetic programming algorithms (SelfCGPs) with a local search in the space of trees is fulfilled to improve their performance for fuzzy rule bases automated design. The local search is implemented with two neighborhood systems (1-level and 2-level neighborhoods), three strategies of a tree scanning (“full”, “incomplete” and “truncated”) and two ways of a movement between adjacent trees (transition by the first improvement and the steepest descent). The Lamarckian local search is applied on each generation to ten percent of best individuals. The performance of all developed memetic algorithms is estimated on a representative set of test problems of the functions approximation as well as on real-world classification problems. It is shown that developed memetic algorithm requires comparable amount of computational efforts but outperforms the original SelfCGP for the fuzzy rule bases automated design. The best variant of the local search always uses the steepest descent and full scanning for fuzzy classifier design. Additional advantage of the approach proposed is a possibility of the automated features selection. The numerical experiment results show the competitiveness of the approach proposed.
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Impact of the reinforcement technique on characteristics of composite tubular structures
Статья научная
Different composite elements including tubular structures are used as support structures in spacecraft optical systems. The compliance with the specified dimensional stability over a wide temperature range, in particular from -269 up to 100 °C, is important for the design of tubular structures. The promising method of manufacturing tubular structures of CM - radial braiding combined with RTM molding method is discussed in this paper. In addition, the paper describes the method of determining the optimal reinforcement technique for a braided perform which allows to reduce geometrical deflections occurring during a molding process. The impact of the reinforcement technique on the dimensional stability of tubular structures is illustrated in this paper by the example of several reinforcement techniques and manufacturing methods. The paper also contains the analysis of these techniques and the determination of the optimal one to comply with the specified characteristics.
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Implementation error of relative measurements
Статья научная
The RNE time scale parameters impact the NSC signal-tracking system operation and the forming of radio navigation signal parameter evaluations had been studied.
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Implementation of Russian sattelite communication system "Gonets" in aircraft monitoring
Статья научная
One of the main problems of air transportation is the problem of continuous aircraft monitoring, which allows to control every specified flight plan, record deviations from the route, and, in case of a crash or an accident, immediately perform the aircraft search, location and rescue. This problem can be effectively solved by means of satellite navigation systems, satellite communication systems and automatic vehicle monitoring systems. The onboard aircraft satellite telemetric terminal “ Gonets D1-M ” is a good option for solving the problem, as it was specially designed for installation in vehicles to record their location, speed and direction. Additionally, it can register a number of other parameters, such as analog / digital input data and sensor readings; that allows to transfer to the control center not only the data on aircraft attitude and speed, but also on the status of its operation. At present, the policy of import substitution is widely implemented on the territory of the Russian Federation, and it has an influence on all spheres of economic activity. This paper gives a presentation of the home-produced satellite navigation system “ Gonets ”, which has a number of advantages in comparison with foreign analogues. The proposed system is being used in the field of sea transportation and has already established itself as practical; so there is a prospect of introducing such a system to the aviation sphere.
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Статья научная
The use of thermal-cycle processing improves the mechanical properties of boat screws of aluminium-silicon alloy АК12.
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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 re- sistance 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 encryp- tion 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 indica- tors by the Rijndael scheme was obtained.
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Статья научная
The article gives the results of problems examination that are connected with estimating the volume of corporate bonded debts. A review of the basic methods to estimate the volume of corporate bonded debts was carried out. There were offered methods of financing innovation activities at defence enterprises and industrial complex in the form of bonded dept including determination of its basic parameters.
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