Software & Systems

Articles of journal № 4 at 2012 year.

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31. Realization of Lyapunov's method of first approximation in the program Maple 12 [№4 за 2012 год]
Author: Чусова Е.В.
Visitors: 11095
The research of stability of the solution of linear systems by using Lyapunov's method of first approximation is presented in the article. Also the properties of the solution are determined: is it stable or unstable, or will it be orbitally stable for the autonomous systems of ordinary differential equations that describe mechanical autonomous dynamic systems. In the article the software implementation of this method in the program Maple 12 is displayed. This method is an effective mean for the research of stability of difference equation systems and systems with aftereffect. Undeniable advantage of this method is following. The system of the differential equations can be investigated about stability without integration, but by constructing the special function with certain properties, and this function is depended from the right parts of the system. The developed program allows to test the system about noninteracting and to construct the phase portrait of the linearized system. This article shows the block scheme of the program and the algorithm of its realization. For clarity we consider the linear equation of free harmonic vibrations and use the program Maple 12 to solve the given task. As a result it has shown that the obtained system is autonomous, the phase portrait has been constructed, and we have revealed that orbital stability of the solution and the solution of the main system is also stable at any moment.

32. Algorithm comparison of methods of complex quantitative quality evaluation of the complex systems [№4 за 2012 год]
Author: Yu.M. Lisetskiy
Visitors: 10913
This work considers the application of various methods of complex quantitative quality evaluation of compound systems to compare and choose the best version of the alternative. As well as the availability of uncertainly in the choice of a method which makes it difficult to obtain an objective assessment of the quality of complex systems, which affects on the validity of the decisions taken in their selection. Offer a solution to this problem, which allows the uncertainly in the choice of a method, removing the inconsistency between the results of different methods of solutions. The algorithm, the essence of which is to define a rational method of the possible combination of methods. An algorithm that minimizes the risk of wrong decisions due to the irrational choice of the method of the possible set of methods for quantitative evaluation of quality systems. Experimental results on real complex systems, confirming the effectiveness of the developed algorithm for comparing the methods package, introducing metrics and expertise in the comparison, evaluation and selection of complex systems are given.

33. Software and algorithms of modeling of nonlinear dynamics by Volterra polynomials [№4 за 2012 год]
Author: Солодуша С.В.
Visitors: 8803
The paper is devoted to the problem of mathematical modeling of nonlinear dynamic input-output systems by Volterra polynomials. The flexibility of this mathematical approach makes it possible to create software for performing experiments on computer. This paper is a continuation of studies on Volterra kernel identification that were initiated by the researchers from L.A. Melentiev Energy Systems Institute SB RAS. The first part of this paper provides information about the algorithms for constructing quadratic integral models for the case of vector input signals. These algorithms are based on the product integration method. The second part of the paper describes a software package for constructing and testing the quadratic integral models of the standard nonlinear dynamic system. The description of heat exchange process in a component of the heat exchanger with independent heat supply served as the standard. The software package is created in an object-oriented programming environment Borland C++ Builder and based on functional modularity. Illustrations of the main part of the user interface are provided. The developed software package was used to process real experimental data. In this paper a software package of mathematical modeling of nonlinear dynamic objects such as «input-output» based on Volterra polynomials is presented. Realized algorithms for constructing integral models are given. Software testing is performed on the reference model of heat exchange.

34. Matrix-topological method for mathematical and computer modeling of temperature fields in electronic modules: programming complex STF-ElectronMod [№4 за 2012 год]
Authors: Madera A.G., Kandalov P.I.
Visitors: 11515
New approach is considered for mathematical and computing modeling for three-dimensional temperature field for EM and its elements, founded on matrix-topological method for mathematical and computer modeling. The method allows to realize the calculations of temperature field for complex electronic systems EM with provision for their real constructive particularities. Computer modeling realized in programming complex STF-ElectronMod for personal and supercomputers. Programming complex has a developed user shell, results of modeling introduced in the manner of distribution colour isotherm of the designs. Designed of the programming complex shown its efficiency and adequacy results.

35. Approaches to analyzing the accuracy of multiagent models of dynamic systems [№4 за 2012 год]
Authors: Dli M.I., Gimarov V.V., Ivanova I.V.
Visitors: 7519
Currently, modeling is the most frequently used methods of analysis objects and processes. However, keeping in mind the complexity of dynamical systems, the simulation is the most efficient kind of modeling. Its application provides an opportunity to analyze hard-formalizable not previously encountered tasks, which are hardly described by analytic expression. Multi-agent models are the one of the varieties of simulation models that reflect the world as a set of separate subsystems – the agents. This article analyzes the role of multi-agent simulation for solving forecasting dynamic systems in adaptation to unsteady external and internal environment. It’s appropriated four types of variation (changes in organizational structure of the model, changes of the agent interaction model, changes of the agent architecture, changes of the internal agent characteristics and parameters), arising during the operation of the multi-agent model. Based on the identified classes of variability it’s proposed to use hierarchical multi-agent models that can adapt to the unsteady conditions of external and internal environment. At the same time in case of using this approach to modeling a problem of evaluating the effectiveness of the model is appeared. Hence, the role of the model performance monitoring based on approximation data analyses algorithms is increasing. In this article a method of the model accuracy estimating, which allows to allocate two types of errors, is proposed. The occurrence of the first type errors determines the advisability of the classification model reconstruction, based on a locally-approximation algorithms, including the initial stage of clustering trajectories. The occurrence of the second type errors testifies to the need to redirect implementation of the classification path to the selected class.

36. Interactive bayesian image matting [№4 за 2012 год]
Authors: Синдеев М.С., Konushin V.S.
Visitors: 10665
Digital matting is a process of extracting foreground object from an arbitrary natural image. The obtained object layer can be used for photomontage or for retouching the source image. Unlike the image segmentation problem, for fuzzy object edges (hair, feathers etc.) it is required to compute a valid opacity channel. The main disadvantages of existing methods are low accuracy and serious difficulties that occur to the user trying to improve the result, because many algorithms lack interactivity and require a full recomputation of the result. This article describes an interactive image matting algorithm developed by the authors, and its software implementation. Problem statement is formalized using mathematical apparatus of probability theory with respect to pixel colors and opacity values. The proposed approach increases quality of the result. Additionally the hierarchic processing increases the algorithm speed for large images. Improvements are confirmed by numerical evaluation and visual comparison. Also we describe an interactive variant of the algorithm, which allows the user to improve the result without editing the image manually.

37. Использование биометрической криптографии в системе управления доступом [№4 за 2012 год]
Authors: Меркушев О.Ю., I.G. Sidorkina
Visitors: 9448
For ensuring protection of a biometric control system with access on the basis of the indistinct ex-tractor, using unprotected communication channels from internal and from external threats it is necessary to exclude transfer and storage of biometric data and the sequence generated on their basis, and also transfer of auxiliary data of an indistinct ex-tractor.The ZK authentication protocol based on biometric fuzzy extractor and ElGamal encryption system is proposed. Advantages, disadvantages and aspects of the practical using of this protocol are discussed. In this work the ZK protocol based on identification on an open key криптосистемы by El-Gamalya is offered. The checking party ciphers any number by means of an open key of the proving party, if the proving party can correctly decipher it by means of the confidential key which is generated by an indistinct ex-tractor, will confirm the authenticity. Advantage of the protocol is lack of need of storage of confidential user data on the party of a subsystem of management of access. It is possible to consider as the main shortcoming that it is necessary for users to store carriers with their open auxiliary data. On the other hand, the information carrier is an additional factor of authentification.

38. Method and code protection software against unauthorized analyze [№4 за 2012 год]
Authors: Shudrak M.O., Лубкин И.А.
Visitors: 9080
The article consider, relevant issue in software protection against unauthorized analyze. In the article authors analyze the existing equipment of binary code protection, descript algorithm of machine instruction analyze with the design of the intermediate language that descript such instructions. The article describes about technique of binary code decompilation and its application possibility in information security sphere. The main object of this work is to develop an efficient algorithm for the binary code analyze. To achieve this goal it is necessary to solve a number of tasks: to develop an effective mechanism for the low-level command analyze with algorithmic representations and conduct testing of the resulting methods. In the second part describes the mechanism of polymorphic code generation, architecture and software interface with the result description. The result was an effective method of reverse engineering and algorithmic representations of binary code linear plots, tested with such tasks as: software protection against unauthorized analysis and analysis of obfuscated code threats. The results show the effectiveness of the proposed technique because increased: the number of operations in the code area, input and output resources and resulting formulas which will inevitably lead to increase resources required to explore this part of the code, and it’s increase the code security against research.

39. Software package for integer lattices basis reduction [№4 за 2012 год]
Authors: Kuzmin O.V., Usatyuk V.S.
Visitors: 10060
This article presents short survey of LLL and BKZ lattice reduction algorithms. Paper contain presents LRT software package for solving SVP and SBP integer lattice problems and generating Goldstein–Mayer lattices. LRT was used to reduce basis of sample lattices for testing algorithms that solve the shortest vector problem (SVP) in euclidean lattices. Were obtained accurate solutions, with error less than 6,1 % of the length of the shortest vector integer lattices (corresponding of Minkowski upper bound) for dimensions 58, 62, 69, 71, 74, 81, solutions took 84, 77, 68, 65, 60, 49 places in the contest algorithms respectively. At 100th dimension of the integer lattice, 32 vectors block size and quadrupleprecision floating-point format, software package LRT effective fpLLL and NTL by 17,2 %, 24,3 %, respectively. LRT is fully compatible with Windows OS and freeware.

40. Model of concurrent execution of program. Estimares of execution time [№4 за 2012 год]
Author: Billig V.A.
Visitors: 8317
Concurrent programming has become one of the main directions of the information technologies development. Concurrent execution models and characteristics connected with them are important for the development of program systems. Such models allow to understand which acceleration may be obtained using concurrency in our program. A model of concurrent execution in computer system with common memory is considered. The running program is regarded as a set of modules connected by data. This link is reflected by graph of dependencies. The goal of the present paper is establishing the estimates of execution time program by one processor – T1, finite number of processors – Tp and unlimited number of processors – T . Such estimates are known for the case when execution times of all modules in our program are equal. We will establish the estimates for the case more interesting for practice when execution times of all modules are different. In the paper we show the execution time for the case of p processors to satisfy the following relations: 1 1 T T Tp T p p


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