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«System analysis and applied information science»

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No 1 (2016)
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System analysis

4-10 1010
Abstract

In article problems of comparison of space pictures with a standard of a digital district map for tasks of updating of cartographical information and monitoring of the territories are considered. The purpose is development of a technique of automated detection of cumulative changes in space pictures concerning a standard of a digital district map in optionally the set analysis window. Researches and development of a technique were made by mathematical simulation of the task in the environment of MATLAB. The last results of researches in the form of the developed technique of detection of cumulative changes of object composition in the orthotransformed and geobound space pictures of the Earth’s surface concerning a standard of a vectorial digital district map are given in article. The main results of comparison of space pictures to a digital district map received in case of tests of the developed technique are shown. Application of this technique allows to automate process already now and to reduce time of the subject analysis of the space information obtained by Earth remote-sensing instruments for topographical mapping.

11-22 852
Abstract

The article deals with the consequences of the existence of special conditions that determine the character of the rapid further development of population processes. The most probable connection of these critical conditions deals with the optimal number of subpopulation groups. These groups are formed by the evolutionary adaptation of the form of restricted access to resources for reproduction. We have proposed a model of population processes, which formalizes the influence of uneven growth rate for two different groups of reproductive sturgeon mortality of migratory fish in the juvenile period of Acipenser gueldenstaedtii development. In the computing environment was investigated the hybrid system, which simulates the effects of the existence of the situation for the population of migrating juvenile disproportionate reduction in the river. Such cases are established by us according to the rapid decline in sturgeon spawning the Volga. For the exploited population threshold effect after the unstable equilibrium with the minimum necessary for the well being of the form number is the count in the implementation of the «collapse». The phenomenon of collapse detached among all scenarios the most valuable long-term degradation of the reproductive group. In addition to the apparent sharp reduction in reproductive performance, threshold effect is reflected in the adverse events previously dominated evolutionary trend for the survival of certain forms of the life cycle of fish in terms of reorganization of the fishery. Informative, that the Volga stellate sturgeon Acipencer stellatus observed some form of non-linearity in the efficiency of spawning and require a different kind of fish-specific mathematical model.

23-28 1810
Abstract

The article is devoted to the problem of regional project portfolio management in context of interaction of the regional development’s motive forces interaction. The features of innovation development on the regional level and their influence on the portfolio forming process considered. An existing approaches for portfolio modelling and formal criterion of the projects selection analyzed. At the same time the organization of key subjects of regional development interaction described. The aim of the article is investigation of informational aspects of project selection in process of the main development’s motive forces interaction and analytic model of portfolio filling validation. At that an inclination of stakeholders to reach a consensus taking into account. The Triple Helix conception using for concrete definition of the functions of the regional development’s motive forces. Asserted, that any component of innovation triad «science–business–government» can be an initiator of regional project, but it need to support two another components. Non-power interaction theory using for investigation of subjects interrelations in process of joint activity proposed. One of the key concept of the theory is information distance. It characterizes inclination of the parties to reach a consensus based on statistics. Projections of information distance onto directions of development axes using for more accurate definition of mutual positions in the all lines of development proposed. Another important parameter of the model which has an influence on the project support is awareness of stakeholders about it. Formalized description of project in the form of fast set of parameters proposes to use for determination of the awareness. The weighting coefficients for each parameter by expert way. Simultaneously the precision of the each parameter setting for all presented projects determines. On the base of appointed values of information distances and awareness amount of each project defines. After the projects ranking filling of the portfolio in the all lines taking into account limits of projects number and available resources occurs.

29-34 897
Abstract

The numerical solution of two-point boundary problem when determining optimal control of dynamical system by means of Pontryagin’s maximum principle is considered. The initial conditions of conjugate set of equations are determined by use of non-gradient random search method.

The non-gradient random search method based on application of stochastic procedures for range of problems solving, including the deterministic ones. When solving the task of optimal control estimation of dynamical system by means of Pontryagin’s maximum principle the initial conditions of conjugate set of equations must be determined, provided that dynamical system’s variables values meet the known terminal conditions Y(tk).

The problem’s solution lie in random selection of vector of initial conditions in some actual range, numerical integration of basic and conjugate systems and subsequent processing of findings. Statistic processing gives the mean and RMS estimations of initial conditions values, providing terminal conditions values hit in some domain Q0 relative to Y(tk) point. For the purpose of ensuring of representative sampling for mean and RMS values estimation the adaptive recurrent search procedure with stepby-step domain Q0 contraction is introduced. The initial conditions of conjugate set of equations on the next search stage are determined on a base of sample estimates of distribution’s parameters.

The example problem solution for thirst-order control object is given. The findings confirm the possibility of proposed approach utilization for optimal control synthesis of dynamical system by means of Pontryagin’s maximum principle.

35-41 1777
Abstract

The problem of obtaining the equations for the a posteriori probability density of a stochastic Markov process with a linear measurement model. Unlike common approaches based on consideration as a criterion for optimization of the minimum mean square error of estimation, in this case, the optimization criterion is considered the maximum a posteriori probability density of the process being evaluated.

The a priori probability density estimated Gaussian process originally considered a differentiable function that allows us to expand it in a Taylor series without use of intermediate transformations characteristic functions and harmonic decomposition. For small time intervals the probability density measurement error vector, by definition, as given by a Gaussian with zero expectation. This makes it possible to obtain a mathematical expression for the residual function, which characterizes the deviation of the actual measurement process from its mathematical model.

To determine the optimal a posteriori estimation of the state vector is given by the assumption that this estimate is consistent with its expectation – the maximum a posteriori probability density. This makes it possible on the basis of Bayes’ formula for the a priori and a posteriori probability density of an equation Stratonovich-Kushner.

Using equation Stratonovich-Kushner in different types and values of the vector of drift and diffusion matrix of a Markov stochastic process can solve a variety of filtration tasks, identify, smoothing and system status forecast for continuous and for discrete systems. Discrete continuous implementation of the developed algorithms posteriori assessment provides a specific, discrete algorithms for the implementation of the on-board computer, a mobile robot system.

Management of technical objects

43-50 1920
Abstract

Wireless Mesh network (WMN) are increasingly becoming popular as low cost alternatives to wired network for providing broadband access to users. A wireless mesh network (WMN) is a communication networks made up of radio nodes organized in a mesh topology. It is also a form of wireless network. Wireless mesh networks often consist of mesh clients, mesh routers and gateways. The mesh clients are often laptops, cell phones and other wireless devices while the mesh routers forward traffic to and from the gateways, which may, but need not, be connected, to the Internet. In this paper, we discuss different radio frequency range in wireless connected to Access Point (AP) and the project from Belarus – China great stone industry park in Mesh network. The China-Belarus industrial park is a territorial entity with the area of approximately 80 sq. km with a special legal status for the provision of comfortable conditions for business conducting. The Park is located in a unique natural complex 25 km far from Minsk, the capital of the Republic of Belarus. It is in close proximity to the international airport, railway lines, a transnational highway Berlin-Moscow. The result of analysis shows distribution of AP and covering services in great stone industry park. Mesh network provides robustness and load balancing in wireless networks communication.

51-59 1831
Abstract

Are considered a situation developed in the field of modelling of fluctuations of vehicles (truck), the attention on low vibroisolation properties of seats is focused. One of the reasons which the weak level of scrutiny of real characteristics of a pillow of a seat is. The technique of tests of pillows of seats is resulted, dependences of change of their parametres on a thickness of a layer pad of a pillow and a rubber category are received.

The advanced mathematical model of a pillow of the seat, providing good coincidence of the peak-frequency characteristic in a strip of frequencies of 2–20 Hz and the block-schema of its realisation in package MATLAB\SIMULIK is offered, allowing more to model fluctuations on a workplace of the driver of a vehicle more precisely. Pillow influence on vibration properties of seats is investigated.

Data processing and decision–making

61-67 1067
Abstract

Computed tomography is still being intensively studied and widely used to solve a number of industrial and medical applications. The simultaneous algebraic reconstruction technique (SART) and Bayesian inference reconstruction (BIR) are considered as advantageous iteration methods that are most suitable for improving the quality of the reconstructed 3D-images. The paper deals with the parallel iterative algorithms to ensure the reconstruction of threedimensional images of the breast, recovered from a limited set of noisy X-ray projections. Algebraic method of reconstruction with simultaneous iterations – SART and iterative method for statistical reconstruction of BIR are deemed to be the most preferred iterative methods. We believe that these methods are particularly useful for improving the quality of breast reconstructed image. We use the graphics processor (GPU) to accelerate the process of reconstruction. Preliminary results show that all investigated methods are useful in breast reconstruction layered images. However, it was found that the method of classical tomosynthesis SAA is less efficient than iterative methods SART and BIR as the worst suppress the anatomical noise. Despite the fact that the estimated ratio of the contrast / noise ratio in the presence of internal structures with low contrast is higher for classical tomosynthesis method the SAA, its effectiveness in the presence of highly structured background is low. In our opinion the best results can be achieved using statistical iterative reconstruction BIR.

Information security

69-76 1951
Abstract

The rapid development of methods of error-correcting coding, cryptography, and signal synthesis theory based on the principles of many-valued logic determines the need for a more detailed study of the forms of representation of functions of many-valued logic. In particular the algebraic normal form of Boolean functions, also known as Zhegalkin polynomial, that well describe many of the cryptographic properties of Boolean functions is widely used. In this article, we formalized the notion of algebraic normal form for many-valued logic functions. We developed a fast method of synthesis of algebraic normal form of 3-functions and 5-functions that work similarly to the Reed-Muller transform for Boolean functions: on the basis of recurrently synthesized transform matrices. We propose the hypothesis, which determines the rules of the synthesis of these matrices for the transformation from the truth table to the coefficients of the algebraic normal form and the inverse transform for any given number of variables of 3-functions or 5-functions. The article also introduces the definition of algebraic degree of nonlinearity of the functions of many-valued logic and the S-box, based on the principles of many-valued logic. Thus, the methods of synthesis of algebraic normal form of 3-functions applied to the known construction of recurrent synthesis of S-boxes of length N = 3k, whereby their algebraic degrees of nonlinearity are computed. The results could be the basis for further theoretical research and practical applications such as: the development of new cryptographic primitives, error-correcting codes, algorithms of data compression, signal structures, and algorithms of block and stream encryption, all based on the perspective principles of many-valued logic. In addition, the fast method of synthesis of algebraic normal form of many-valued logic functions is the basis for their software and hardware implementation.

Information technologies

78-83 894
Abstract

Due to the constant increasing of electronic textual information, modern society needs for the automatic processing of natural language (NL). The main purpose of NL automatic text processing systems is to analyze and create texts and represent their content. The purpose of the paper is the development of linguistic and software bases of an automatic system for processing English publicistic texts. This article discusses the examples of different approaches to the creation of linguistic databases for processing systems. The author gives a detailed description of basic building blocks for a new linguistic processor: lexical-semantic, syntactical and semantic-syntactical. The main advantage of the processor is using special semantic codes in the alphabetical dictionary. The semantic codes have been developed in accordance with a lexical-semantic classification. It helps to precisely define semantic functions of the keywords that are situated in parsing groups and allows the automatic system to avoid typical mistakes. The author also represents the realization of a developed linguistic database in the form of a training computer program.



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ISSN 2309-4923 (Print)
ISSN 2414-0481 (Online)