Software & Systems

Articles of journal № 4 at 2012 year.

Order result by: Public date | Title | Authors |

11. Noise combating layered space block code [№4 за 2012 год]
Author: Гофман М.В.
Visitors: 5848
The transmitter is equipped with multiple transmit antennas can transmit multiple signals simultaneously, and the receiver uses multiple receiving antennas, allows more reliable reception. Creating space code, which will be used in the multi-antenna communication systems, we have to choose between the speed of transmission and noise combating. This article presents noise combating layered space code. Parameters allow you to get the code of its implementation, focused on a particular channel with fading. Feature of the code is that it does not have symbolic redundancy, and the fact that each of the transmit antennas are always involved. The proposed code uses the spatial, temporal and frequency types of diversity.

12. Parallel software package for optimal development Of dynamic flow network [№4 за 2012 год]
Authors: Григоренко Н.Л., Жарков А.В., Пивоварчук Д.Г., Popova N.N.
Visitors: 10415
In this paper the model of the dynamic transport network is suggested. The dynamic transport network is defined as the delivery network which connects some amount of supplies, distributers and consumers. Parameters of this network (demand and consumption) stochastically change depending on the time. In this paper the problem of optimal development of such network is researched. Optimal development is the development, the object of which is the maximum satisfaction of consumers’ demand over the model time. The parallel algorithm of optimal development network problem solving is suggested. The necessity of creation such an algorithm is conditioned by large amount of computational operations, which are needed for problem solving of real transport network graphs. The suggested algorithm is taken as a basis of the software package, which allows solving the given problem at supercomputers. The ADOT language, which is the extension of DOT language, is described. This language allows representing the input data in user-friendly form. The approbation of this software package is executed at Lomonosov supercomputer. The graphics of algorithm time solving, speedup and efficiency are represented. The scheme of optimal task scheduling development is described in this paper.

13. 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: 7545
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.

14. The experimental cloud computing environment in institute of Mathematics and Mechanics Ural Branch of RAS [№4 за 2012 год]
Authors: Ermakov D.G., Усталов Д.А.
Visitors: 11725
This paper considers the problem of providing a scalable computing infrastructure to consolidate computing equipment used for developing and debugging software as well as for the didactic support of educational courses. Software specifications are formulated and the following existent solutions are reviewed and compared: Eucalyptus, OpenNebula, OpenStack, and Nimbus. A decision is made to perform an experimental deployment of the OpenNebula suite based on the KVM hypervisor and the GNU/Linux operating system. OpenNebula is an open source software designed to control the cloud environment of the Infrastructure-As-a-Service class. The KVM hypervisor was developed by Red Hat and is supported by OpenNebula as a default virtualization solution. The available computational resources of the Institute of Mathematics and Mechanics, Ural Branch of the Russian Academy of Sciences, and dedicated backend nodes for the experimental cloud computing environment are described. The configuration of a typical cloud computing node under the Scientific Linux 6.1 (x86_64) operating system with the LVM, KVM, and libvirt technologies is presented. The cloud environment architecture is presented at both logical and physical levels. Some difficulties concerning the SELinux security system and the fault-tolerance performance are described. A plan of further work in the following directions is suggested: integration with the Active Directory domain system, application of the network-attached storage to keep the images of virtual machines, migration to the MySQL relational database, and the testing and presentation of scalable Web services to cloud computing end users at the IMM UrB RAS.

15. Qualitative and quantitative characteristics of the open information systems [№4 за 2012 год]
Authors: Ефимов И.Н., Жукова С.А.
Visitors: 14686
This article deals with the method of the formation of the virtual laboratory complexes and its location through the use of an automated system in the open information space to carry out the remote experiments. As such, the virtual laboratory complex and the automated system are the effective tools to integrate the intellectual assets, user-friendly and often indispensable tool to solve the scientific, educational and business problems. The research resources include the intellectual assets (object models and modes of their research, computer programs of research, experiments results). We determined the main processes of the formation of the virtual laboratory complexes: problem statement, preparation for the formalization, formalization, algorithm elaboration, building of the multitemporal models or problem solution using the hardware and software system; operation with the simulation model of the object; and analysis of the results and search for knowledge retrieval. The automated system and the virtual laboratory complexes are developed in accordance with the principles of the open systems and ensure the following characteristics achievement: ergonomics, it’s handy and practical tool for the scientific, educational and business researchers; scalability, it’s expandability by users and virtual laboratories; it supports the tasks of the several basic groups of users (science, education, business); it has a mechanism to expand according to the types and number of the virtual laboratories; interoperability, it integrates and manages by diverse software and hardware, by process-oriented research; mobility, it supports the virtual laboratories, regardless of their hardware.

16. Problem of decision-making support in estimation of investment projects of foundry plants on the basis of moulding lines [№4 за 2012 год]
Authors: Зенькович М.В., Древс Ю.Г.
Visitors: 8686
Methods and software enabling the estimation of efficiency and the comparisons of alternative designs of foundry plants on the basis of moulding lines are discussed. Problem of estimation of efficiency of investment projects of foundry plants on the basis of moulding lines is formulated in the terms of decision theory. Presented approach is based on the reduction of multicriterion problem of estimation of investment project to one-criterion problem. Set of outcomes of acceptable alternatives, set of vectorial estimations of outcomes, mapping of set of outcomes of acceptable alternatives to set of vectorial estimations of outcomes and structure of decision maker’s preferences are described. Decision rule which allows to carry out required operation over the set of acceptable alternatives is formulated. Application of simulation for estimation of technological and constructional decisions, which was made during the plant design, is the central feature of presented approach. Model of moulding line refers to discrete-event class. Object-oriented approach was applied for designing of the model and programming language C++ for its implementation. Application of detailed simulation model of moulding line allows to carry out an accurate estimation of technological and constructional characteristics of involved projects. Presented methodology of estimation of investment projects of foundry plants on the basis of moulding lines is tried-and-true method which applies on the phase of designing and engineering of foundry plant.

17. Scientific Heritage of Russia Digital Library: Construction and sources aggregation philosophy [№4 за 2012 год]
Authors: N.E. Kalenov , Савин Г.И., Serebryakov V.A., A.N. Sotnikov
Visitors: 23531
A construction philosophy for digital information resources by digital libraries tools is considered. Russian Scientific Heritage Digital Library Project is under consideration. Place and role of the Russian Scientific Heritage Digital Library among similar local and international projects where defined. Basic architecture statements and data aggregation tools for digital library construction were presented. Sources, types and structure of the digital objects were discussed. Data integration and federation concept as a main stone for the common education and scientific space is presented. Collaboration across national boundaries and information sources defined as imperative.

18. An efficient application mapping algorithm for multiprocessor systems [№4 за 2012 год]
Authors: Kiselev E.A., Аладышев О.С.
Visitors: 9153
This article describes a new application mapping approach for multiprocessor systems based on simulated annealing algorithm. The authors propose a model of multiprocessor system, which takes into account the heterogeneity of computing and communication resources, as well as a model of a parallel program based on the identification of typical communication operations between theprogram threads.The authors propose a parallel implementation of the algorithm simulation annealing to improve the quality of application mapping on the resources of multiprocessor computer system.The authors investigated the effect of competition in the network at the application work time.

19. A dense stereo matching algorithm based on ground control points and plane labeling [№4 за 2012 год]
Authors: Кривовязь Г.Р., Птенцов С.В., Konushin A.S.
Visitors: 11667
In this work a new dense stereo matching algorithm is proposed. The algorithm is based upon a recently introduced idea of non-local cost aggregation on a minimum spanning tree that includes all image pixels. Themainfeatureoftheproposed algorithmisto switchfrom disparity space to plane space: the disparity in each pixel is deduced from equation of a plane assigned to that pixel. A way of estimating the set of planes, which are used to approximate the scene, is described. For this purpose, ground control points (GCPs) are used. GCPs, derivedas a result of image matching, are also exploited to regularize the solution. Theresultsofalgorithmevaluationononeofthe moderndatasets (published in 2012) are provided. Thedatasetconsistsof 194 streetviewimagepairs. Thediscussion of possiblewaysoffurtheralgorithmimprovement concludes the paper.

20. Complex of the programs and algorithm of calculation of the fractal dimensions and a linear trend of the time series [№4 за 2012 год]
Authors: Крылова О.И., Цветков И.В.
Visitors: 15383
One of the upcoming trends of modeling of complex systems is application of a multifractal dynamics method. The multifractal dynamics models are based on the description of the dynamics of processes represented by multifractal curves. The whole observation time period is got into intervals with defined values of a linear trend characterizing the trend of the value of interest. On each interval, for time series values, a fractal dimension D should be defined. This work offers a new algorithm of computation of a fractal dimension D of the time series envelope in the form of a piece linear function. Computation of the fractal dimension of the time series envelope is based on calculation of the time series envelope length while grouping initial data by different ways. In order to improve computation accuracy, the algorithm uses a trend channel development procedure and rationing of first-calculated fractal dimension values based on the results obtained for the specially generated stochastic time series inside the trend channel.

◄ ← Preview | 1 | 2 | 3 | 4 | 5 | 6 | Next → ►