“Informatics and Applications” scientific journal

Volume 1, Issue 1, 2007

Content   Abstract and Keywords   About Authors

DEVELOPMENT OF PUGACHEV FILTERING FOR STOCHASTIC SYSTEMS

• I. N. Sinitsyn.  IPI RAN, sinitsin@dol.ru

Abstract:  Statistical methods of information processing (filtering, extrapolation, interpolation etc) in stochastic systems (StS) are the basis of modern statistical informatics. Analytical survey and main tendencies of nonlinear conditionally optimal Pugachev filters (PF) for StS are considered. Pugachev filters for regular and nonregular, continuous and discrete, Gaussian and non-Gaussian StS are discussed. Interconnection between PF and Kalman filters including various statistical criteria is given. Problems of joint filtering and recognition and PF trends are considered.

Keywords:  stochastic systems (StS); Pugachev filters

MEANS PROVIDING APPLICATIONS FAULT TOLERANCE

• V. Zakharov.  IPI RAN. vzakharov@ipiran.ru
• V. Kozmidiady.  IPI RAN. kozmidiady v@tochka.ru

Abstract:  The problems of fault tolerant servers creation, caused by nondeterminate applications behavior, are considered. A formal model based on resources and events and describing an application behavior is described. The algorithms of an application execution logging on the reserved cluster node, of restoring and continuation of running after main node fault are proposed. In the proposed approach, both fault and recovery are hidden from the client who experiences slight service quality degradation at worst.

Keywords:  applications server; transparent fault tolerance; process; resource; event; check point; determinate

MULTICHANNEL QUEUING SYSTEM WITH FINITE BUFFER AND UNRELIABLE SERVERS

• A. Pechinkin.  IPI RAN. apechinkin@ipiran.ru
• I. Sokolov.  IPI RAN. isokolov@ipiran.ru
• V. Chaplygin.  IPI RAN. vchaplygin@ipiran.ru

Abstract:  Multichannel queuing system with a semimarkovian input flow, a phase type distribution of the servicing, a finite buffer and unreliable servers refusing independently one from other and regargless of the whole process of refusals and restorations is considered. Mathematical relations allowing calculation of the main stationary characteristics of system functioning are found under some different variants of the process of refusals and restorations.

Keywords:  queuing system; unreliable servers

A NEW METHOD FOR THE PROBABILISTIC AND STATISTICAL ANALYSIS OF INFORMATION FLOWS IN TELECOMMUNICATION NETWORKS

• D. Batrakova.  IPI RAN. daria.batrakova@gmail.com
• V. Korolev. Faculty of Computational Mathematics and Cybernetics of Moscow State University; IPI RAS. vkorolev@comtv.ru
• S.Shorgin.  IPI RAN. sshorgin@ipiran.ru

Abstract:  A new method is proposed for the analysis of the stochastic structure of chaotic information flows in convergent telecommunication networks. The proposed method is based on a stochastic model of a telecommunication network which has the form of a superposition of some simple sequential-parallel structures. This model quite naturally generates mixtures of gamma-distributions for the network operation execution time. The parameters of the mixture of gamma-distributions characterize the stochastic structure of chaotic information flows in the network. The problem of statistical estimation of the parameters of gamma-distributions is solved by the EM-algorithm. To trace the variation of the stochastic structure of information flows in time, the EM-algorithm is applied for the moving window. The software for the division of distribution mixtures is developed and documented. The real input data is used. The interpretation of results is given.

Keywords:  telecommunication networks; information flows; division of mixes of distributions; method of a moving window; software for division of distribution mixtures

LINGUISTIC SIMULATION FOR MACHINE TRANSLATION AND KNOWLEDGE MANAGEMENT SYSTEMS

• E. B. Kozerenko. IPI RAN. kozerenko@mail.ru

Abstract:  This paper is dedicated to the vital problems of creating semantic-syntactic presentations for the systems of machine translation and extraction of knowledge from natural language texts. The purpose of our studies is the construction of an integral linguistic model on the basis of a synergetic approach, which uses linguistic knowledge, statistical methods, and mechanisms of machine learning for the extraction of new grammar rules from text corpora and disambiguation of language structures. To formalize linguistic knowledge, we have developed a new Cognitive Transfer Grammar which is a semantically motivated version of a generative unification grammar. For the preparation of system training components and obtaining statistical data about language structures, a multilingual resource is being created, comprising a Treebank and a corpus of semantically aligned parallel texts in Russian, English, and a number of other European languages.

Keywords:  machine translation; grammar formalisms; linguistic model; parallel texts alignment; semantics; syntax; phrase structure

THE SYMBOL MODEL OF INFORMATICS KNOWLEDGE SYSTEM IN HUMAN-AUTOMATON ENVIRONMENT

• V. D. Ilyin.  IPI RAN. vdilyin@ipiran.ru
• I.A. Sokolov.  IPI RAN. isokolov@ipiran.ru

Abstract:  The paper describes the authors approach to the construction of informatics knowledge system in human-automaton environment. This system is investigated as means of formalized representation of scientific results. The bases of conception of the construction and application methodology of this system are described. This methodology is studied as scientific foundation for automation of research, design, and education.

Keywords:  informatics; symbol; symbol model; human-automaton environment; knowledge system; symbol modeling in human-automaton environment