Software & Systems

Articles of journal № 3 at 2015 year.

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1. Creation of automated control system for unmanned spaceflights in near-earth space [№3 за 2015 год]
Authors: Arepin Yu.I., Doronkina A.N.
Visitors: 10499
Nowadays a creation of automated control systems for unmanned space missions in near-Earth space, for a spacecraft or a group of them is relevant. One of the central problems in the mission control is ballistic and navigation support, including setting targets, developing methods and algorithms to solve them, a complex of computational procedures, which are used later in the spacecraft flight control. One of the tasks of ballistic and navigation support is to determine the parameters of spacecraft motion in space (current and projected). Navigation gives you the ability to define and correct a space mission, to provide guidance, convergence, disorbit, etc. The analysis of the operation processes and the problems of creating automated control systems for mission control is impossible without a mathematical model or an aggregated set of components’ models, which reflect the properties of the modeling object. One of the main problems of spaceflights is a technical exploration of space, designed to strengthen the defense power of the Russian Federation and national security. Implementation of the pressing problems in this area for the Russian Federation is possible to base on the creation of spacecraft groups using highly elliptical orbits. In this regard, the article discusses the urgent task of building the satellite systems of continuous coverage of the Earth in highly elliptical orbits. This problem is reduced to finding the extremum of a function of a finite number of parameters, the function must have the meaning of a geocentric angular distance. The number of parameters is large, the criterion function is composite. To facilitate the analysis and simplify the calculations, the authors suggest the variants of problem dimension reduction, as well as the parameters of the operating effect of spaceflights automated control systems.

2. The optimal control software environment for a nonlinear system class via quadratic criteria [№3 за 2015 год]
Authors: A.P. Afanasiev, S.M. Dzyuba, Emelyanova, I.I.
Visitors: 8202
The paper presents a distributed software environment for a feedback optimal control synthesis. The control is performed by one class of nonlinear systems via quadratic criteria. This software environment is based on a special method of successive approximations. The successive approximation method convergence is guaranteed in the case of a single optimal control. The software implementation is performed by means of symbolic computation in a distributed environment.

3. Structural analysis through the finite differences method with the use of MathCAD approximating functions [№3 за 2015 год]
Author: Bakushev S.V.
Visitors: 9430
The question considered is the approximation of problem-solving results for the deformable solids me-chanics through finite differences with MathCAD built-in functions. It is shown that the most acceptable approximant in a MathCAD package for deformable solid mechanics problem-solving when required parameters express one in terms of other by derivatives is a cubic spline interpolation using cubic spline with function prediction. The statement is proved that if the required parameters of the task are expressed one via another using derivatives, then the re-execute of the differences operators for their definitions, as well as linear approximation data for out-of-node definitions, is un-acceptable and leads to significant errors. Furthermore, using the first derivations sequence for defying required pa-rameters of the task leads to data loss and calculation impossibility. The article considers an actual example of bending uniformly loaded hinged steel bar.

4. Neural network approach to evaluate a characteristic exponent of Levy process on Bandorff-Nilsen distribution example [№3 за 2015 год]
Authors: Belyavsky G.I., Puchkov E.V., Lila V.B.
Visitors: 7887
Application of the method of principal components and the generalized method of principal components to analyze data is not always reasonable, because the moments of necessary order don’t always exist in the analyzed distribution. At the same time, the interest in Levy processes continues to increase due to their numerous applications, but the principal component method is not applicable to the Levy process is. An important feature of the Levy process, which simplifies the analysis, is that the Levy process is completely defined by a complex-valued function of a real argument. It is a characteristic exponent. To identify the Levy process is to find the estimate of the characteristic exponent in the training set. The property of independence and homogeneity of Levy process increments allows using the increment of the process as a learning sample. The article considers the problem of building a neural network model for estimation of the characteristic exponent at a given interval of the argument. To estimate the characteristic exponent of the Levy process the authors propose the stochastic analogue of the adaptive neural network learning algorithm that uses the potential functions of Lanczos. The learning algorithm is tested on a hyperbolic Bandorff-Nilsen distribution. The hyperbolic distribution is a mix of normal laws, which allows generating a training sample with little effort. As a result the neural network has calculated an estimation of the Levy process characteristic exponent with a satisfactory degree of accuracy.

5. A cognitive conceptual model of financial and economic stability of the enterprise [№3 за 2015 год]
Authors: Butenko D.V., Butenko L.N.
Visitors: 8364
The article discusses the application of the conceptual methods of analysis and modeling in relation to the fi-nancial-economic area. The analysis results of the existing models of financial-economic stability and homeostatic approach allows us to develop a new model for the task of a decision-making support in terms of financial and economic sustainability of a production and trading enterprise. The article shows this model and presents its advantages and application, in particular, a prognostic aspect and the prospect of creating an automated system to support the enterprise management process. The model represents a connected graph in the form of six-pointed star consisting of two triangles, one of which describes the economic, and the second describes a financial component of the enterprise. The components of the model are linked by di-rect, reverse and cross-links, which allows analyzing the current situation and forecasting results of control actions on the components in order to achieve a stable position of the company. The proposed model is new, it has been tested on the exist-ing enterprises. It was proved that the model allows automating the process of management decisions support.

6. Software for the analysis of technical systems fault tolerance based on the graph vertex integrity [№3 за 2015 год]
Authors: Bykova V.V., Kirillov Yu.I.
Visitors: 6204
Nowadays the study of graphs integrity measures is of current interest due to the use of graph models in the design of fault-tolerant complex technical systems. Vertex integrity is one of the determined measures of graph integrity. The system is considered to be ful-ly operational if the corresponding graph is connected. The vertex integrity evaluates the partial loss of system performance due to the com-ponent failure. The graph vertex integrity G = (V, E) is a value of I(G) = min S  V {| S | + w(G – S)}, where w(G – S) is the order of the highest component of the graph connectivity G – S, which is obtained from G by removing all elements belonging to S. The value of w(G – S) char-acterizes the size of the largest fragment of the system, which was formed after the failure of all elements of S. The definition of a vertex in-tegrity of a graph was introduced by Bagga, Barefoot, Entringer and Swart. It is known that the problem of computing I(G) for a general graph is NP-hard. To find the exact value of the vertex integrity we have to know all separators of the graph. This paper presents an algo-rithm and software for finding an approximate value of I(G). The proposed algorithm is limited by considering all minimal separators, there-fore it gives only an upper bound of the vertex integrity. The algorithm labor intensivity polynomially depends on the number of vertices and minimal separators of the input graph. The experimental results showed that the calculated estimates are good and often achievable. When carrying out computational experiments, the exact value of the vertex integrity was received by an exhaustive search of all separators of the input graph.

7. Speaker clustering using enhanced self-organizing incremental neural networks [№3 за 2015 год]
Authors: Vagin V.N., Ganishev V.A.
Visitors: 9370
The paper describes the use of an unsupervised learning method based on self-organizing incremental neural networks for the problem of speaker clustering. I uses a set of mel-frequency cepstral coefficients as a user model. This set is obtained by applying a special filter to the sound signal frequency, which was transferred into the mel-frequency scale ("mel is an abbreviation of “melody”). The main difference of this work is the consideration of the dynamics of mel-frequency cepstral coefficients changing, which also contains information about the user. The possibility of new unique users emergence in the system while operating makes it impossible to use the major-ity of neural network classes, because learning on a new data set will lead to malfunction, “forgetting” of prior learn-ing. Neural networks for on-line learning impose a limit on the maximum number of clusters, that is unknown for this problem, and, in general, they require a priori knowledge of the input data (to establish thresholds, etc.) that is difficult to achieve in practice. Self-organizing incremental neural networks allow lifetime learning, that means learning during the operation stage, and do not require any a priori knowledge about the users or their quantity. A dynamic neural net-work structure makes it possible to create an unlimited number of new clusters for new previously unregistered users. Thus, this method allows building a flexible speaker clustering system that adapts itself to the changing input data.

8. Estimation of advanced characteristics of airoplanes using cluster analysis [№3 за 2015 год]
Authors: Vestyak V.A., Malashkin A.V., Malashkin A.A.
Visitors: 8297
The development of new types of light airplanes requires justification for passenger and weight-lifting capacities. The fundamental works [2] describe crucial problems of aircraft development for various purposes and methods of their solutions. The problems also concern the issues of general design of airplanes’ particular parts. The article pays attention to finding a solution for automation of the design objective: the effective algorithm of modified cluster data analysis for passenger air travel was developed and software-implemented. In short, based on the literature review, the authors explain the necessity of designing a local airplane with passenger capacity up to nineteen people. The development of an airplane for a specific airline operation takes into account the following parameters: transit range, the amount of passengers and weight of commercial cargo. In case of using cluster analysis classic approaches (K-means or K-medians with a finite number of clusters), in each cluster there will be airline operations exceeding aircraft capabilities with cluster specifications. Moreover, each airline operation represents a point in a three-dimensional space, each axis has a different dimension (kilometres, the amount of passengers, kilograms). Therefore, the problem of measuring the distance in this kind of a dimension arises: it is impossible to select the effective metric in such a dimension. That's why instead of the above-mentioned classic approach the authors used the original method of changing from three-dimensional to one-dimensional space for cluster analysis. It allows using a general Euclidean metric. The criteria of stopping the algorithm is offered and justified. The actual data of 1017 airline operations was processed. The acquired results can be used by aircraft designers and engineers working on aircraft concepts.

9. Bioreactors database [№3 за 2015 год]
Authors: Vorobyova E.S., Ivanov S.I., Menshutina N.V.
Visitors: 8486
Nowadays, much attention is paid to the development of biotechnological processes, an important element is the bioreactor. Taking into account the development of modern industry, the number and variety of produced bioreactors is constantly increasing. In order to systematize industrial bioreactors data using Microsoft SQL Server 2008 R2, the “Bioreac-tors” database was created. It systematizes the devices themselves as well as their basic technical and operational characteris-tics. For easy operation of the developed software it is necessary to provide the most comfortable user interaction with the program. Thus, using the Microsoft Visual Studio 2010 software package, an application was created. It represents a database graphical interface. The application allows you to obtain information about the bioreactors, manufacturers, tools, automation and other data in tables with the option to sort information. The tables in the database were developed for entering infor-mation about new models, companies and measuring instruments, and for correcting and updating existing information. A part of the software windows are fitted out with graphical regions to visualize the design of a biotechnological apparatus. As the result, the software product includes an interface adapted for users without knowledge of SQL. A software module was created for automatic data enrichment of the software product. It allows automatically analyze, collect and classify infor-mation from the web sites of manufacturers of bioreactors to fill and update existing databases. The approach, which was used in the module, is based on the DOM tree analysis, as well as on the combination of such methods as HtmlAgilityPack and Data Extracting SDK.

10. The methods of optimal automated formation of standings [№3 за 2015 год]
Authors: Glushan V.M., Kazharov A.A., Ponomarev V.K.
Visitors: 7645
The article examines the questions of prompt sport competitions drawing and creation of standings by using computer tech-nologies. This process is rather time-consuming if done by hand and with a large number of contestants. The aim of the draw is to disperse the players in different groups so that all groups would have about the same overall rating and at the same time each group would consist of players from different regions. Drawing of the tournaments with only one competitor from each region is not much of a problem. The situa-tion becomes much more complicated when several competitors apply from the same region. In this case the task acquires two criteria. Re-gional factor is necessary to be considered, because it happens often that there are players in the list of participants who potentially have common interests and that can lead to various kinds of unsporting collusions. The article discusses some of traditional and non-traditional methods of drawing and analyzes their capabilities. Snake heuristics was used for automated generation of optimal tournament tables. The algorithm and software is developed on its basis supported by research on sufficiently big number of test cases. According to preliminary es-timates of the competent members of the International Table Tennis Federation (ITTF) jury, the software product meets quality requirements of automatically generated tournament tables and allows reducing their formation time repeatedly.

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