Systems and Means of Informatics scientific journal
Volume 28, Issue 1, 2018
Abstract: On the basis of initial and central moments, the theory of analytical synthesis of suboptimal and modificated filters (SOF and MSOF) for differential (on manifolds) nonlinear stochastic systems (StS) is developed. The authors suppose that: (i) state equation includes Gaussian and Poisson noises; and (ii) observation equation contains Gaussian noises only. For SOF synthesis, the authors use normalized densities and for MOF, unnormalized densities. Questions of instrumental accuracy and sensitivity are discussed. The algorithms are the basis of the software tool StS-Filter 2018. Two test examples for angular information-measurement system are given. Some generalizations are mentioned.
Keywords: a priori distribution (density, characteristic function); method of initial moments; method of central moments; modificated method of initial moments; modificated method of central moments; normalized distribution; unnormalized distribution; stochastic system; suboptimal filter; angular information-measurement system; Gaussian noise; Poisson noise
TO THE RELIABILITY OF AN INFORMATION-TELECOMMUNICATION SYSTEM: AN APPROACH TO RECOGNITION OF RELIABLE SOFTWARE CHARACTERISTICS
Abstract: Issues of reliability assessment of newly created and existing information and telecommunication systems (ITS), traditionally routine and formal, are considered as an inalienable part of the design process. To determine the reliability of a system, the holistic methodology is proposed. Within the framework of this methodology, firstly, specific quantitative characteristics of reliability, which correspond to qualitative indicators determined at different stages of system development, are specified. For the hardware component, this is the availability factor, which is set by the standard indicators of trouble-free operation of the nodes. For software, this is a set of probability characteristics that take into account the specifics of different reliability indicators that characterize the quality of programs. Secondly, for determination of the chosen reliability characteristics, the relations based on the basic methods of mathematical statistics are given. Thirdly, to determine the probability characteristics, recommendations for collecting statistics at different stages of the life cycle of the system are given.
Keywords: information and telecommunication systems; system design; reliability; probability reliability characteristics
Abstract: The brain study is the one of the most popular research area in contemporary neuroscience. It accumulates efforts of broad research groups involving different kinds of experts: psychologists, mathematicians, etc. The main problem in this area is how to localize cerebral cortex activity using experimental data. This problem is critical for all neuroimaging methods (functional magnetic resonance imaging, electroencephalography, magnetoencephalography (MEG), etc.). In the paper, MEG data are considered. Magnetoencephalography is anon- invasive neuroimaging technique which allows recording extra weak magnetic fields generated by neurons in human brain. Sources reconstruction using MEG data is an ill-posed inverse problem. The paper considers the Bayesian derivation of the inverse problem solution for MEG data. The main steps are described and necessary calculations are provided. Particular attention was paid to such advantage of the Bayesian approach as universality. It was shown how other popular methods which are widely used in research could be obtained within the unified framework. A generalization to the group-wise experiment is also considered. The paper also provides possible ways of further improvement of the MEG inverse problem solving techniques using the Bayesian approach.
Keywords: Bayesian approach; magnetoencephalography; inverse problem; ill-posed problem; a posteriori maximum estimation; optimization methods
Abstract: Volumetric models are widely used in various schemes of threedimensional (3D) reconstruction: silhouette-based reconstruction, multiview stereo, and SLAM (simultaneous localization and mapping). The volume containing the scene to be reconstructed is divided by a regular grid into small cubes called voxels. This volume is usually bounded by an axis-aligned cube (bounding box). The preliminary to 3D reconstruction is to estimate a bounding box. The paper describes four methods of initial bounding box estimation and provides their experimental evaluation and comparison. The presented methods rely on known camera matrices and do not require any prior information about the scene.
Keywords: voxel; volumetric model; bounding box; 3D reconstruction
Abstract: The article continues the series of articles on modeling of errors of independent users in forming of semantic net which is the basis for the distributed technology of concrete historical investigation support. The article is devoted to the description and rationale of the approach to modeling of organizational measures designed to find and correct these errors. The proposed approach is to expand the semantic net model which is based on the concepts of graphodynamics and the Barabasi-Albert model with the mechanism of parallel fixation of mistaken and appropriate nonmistaken user actions by including a new mechanism of user roles and various forms of their activity. In the process of applying this approach, the analysis of influence of different classes of errors on the network quality was made. Experimental studies of effectivity of organizational measures of finding and correction of semantic network errors were undertaken using this model.
Keywords: semantic net; model; user errors; organizational measures; error correction
Abstract: In the process of solution of inverse problems of chemical kinetics, one often faces the ambiguity of definition of certain kinetic parameters. The ambiguity of the inverse problem is that the description of any mathematical model must reflect some chemical reactions in a certain area of input parameters.
Keywords: inverse problems; chemical kinetics; informativeness of the experiment ; region of uncertainty
REGARDING SYSTEMIC AND TECHNICAL PROBLEMS OF APPLYING INTELLECTUAL DATA ANALYSIS FOR PROVIDING INFORMATION PROTECTION IN SITUATIONAL CENTERS
Abstract: The article is dedicated to problems of applying intellectual data analysis for providing information protection in situational centers. The authors present the analysis of general problems of information security in cloud computational systems. The authors consider general components of information protection systems which, at present, apply artificial intelligence technologies to some extent. The authors suggest propositions for extending the application area of the technologies to protect the information. The current regulatory base of information security in cloud computational systems is analyzed.
Keywords: situational center; automated systems; cloud computational systems; informational security; data security threats; functional security; artificial intelligence; machine learning
Abstract: The analysis of erratic statuses of the distributed computing systems on the example of OpenStack, caused by the absence of synchronization between components of a cloudy computing environment and, also, probable sources of their origin are considered. Detail analysis of journal records is provided in the analysis of one of the listed erratic statuses of software platform of OpenStack. The method of the analysis of similar situations is shown. Creation and maintenance in current state of an information model of a managed cloudy computing environment is suggested. The necessity to use such model for execution of requirements of positive control of a cloudy computing environment and provision of high-quality cloudy services of such types as service, platform, infrastructure, network functions, chains of network functions is substantiated.
Keywords: distributed computing systems; cloudy computing environments; OpenStack; RabbitMQ; Nova; Neutron; analysis of erratic statuses; information cloudy network infrastructures
MODELING OF SECURE ARCHITECTURE OF DISTRIBUTED INFORMATION SYSTEMS ON THE BASIS OF INTEGRATED VIRTUALIZATION
Abstract: Secure architecture of distributed information systems can be built on the basis of virtual machines. Each virtual machine carries out strictly particular functional. It allows defining virtual machines which are solving problems of information security only. In the paper, the influence of the architecture using virtual machines for ensuring information security on collecting speed and data transmission between elements of the information system is considered. Research of loss of speed by transfer and reception confirmed possibilities of creation of secure architecture by means of isolation of virtual domains with virtual servers of security.
Keywords: distributed information security; distributed information system; virtualization
Abstract: The software-defined networking (SDN) technology in comparison with traditional IP networks allows programming the network's behavior using a centralized controller. In this case, forwarding devices deal only with forwarding frames based on flow tables loaded into them by the controller. Flow tables are built on the controller during the processing of information about traffic flows arriving at forwarding devices. The above properties of the technology were used to create the SDN load balancer for devices of secure networks. The article discusses the architecture and software of the balancer. Descriptions of schemes and results of experiments on load balancing for such devices as L3-VPN (Level 3 Virtual Private Network) gateway, TLS (Transport Layer Security) gateway, and IDS (Intrusion Detection System) are given.
Keywords: software-defined networking (SDN); controller; OpenFlow; VPN gateway; TLS; intrusion detection system; IDS; load balancing; DPDK; Open vSwitch; Beacon
Abstract: This work presents the method of load balancing on level 3 virtual private network (L3-VPN) gateways to scale secure communication channels between data centers. The method is based on the software-defined networking (SDN) technology. The load balancing and channel fault tolerance (Active- Active) algorithms are described in detail.
Keywords: VPN-gateway; load balancing; scaling; elastic datacenter; software- defined networking (SDN); OpenFlow
Abstract: In a number of authentication methods, there are inaccuracies due to the impossibility or complexity of reproducing the authentication data exactly coinciding with the data specified by the user during initial registration in the information system. Such methods include, in particular, biometric methods as well as some methods based on graphic passwords. The paper explores the possibility of using the fuzzy vault scheme to correct such inaccuracies and provide high resistance to the selection of authentication data in a keyboard authentication system and in a graphical password authentication system.
Keywords: fuzzy vault; authentication; keyboard handwriting; graphic password
Abstract: The technology of situational resource planning based on online services is proposed. A key role is assigned to the expert planner, who interacts with online services for forming the situation portraits and resource allocation, assesses the situations, forms systems of mandatory and orienting rules, makes requests for the calculation of plans, and estimates their feasibility and effectiveness. The foundations of methodologies for situational online resource allocation and budgeting taking into account the priorities of expense items are outlined. Formulation of the linear problem of resource allocation based on the system of mandatory and orienting rules and the method of target displacement of solution executed by the resource planning service are presented. The statement and the principle of solving the budget planning problem are given, taking into account the uncertainty of the data represented by numeric segments. The online service "Cost planning" used to solve the problems of planning budgets (state, corporate, etc.) is briefly described.
Keywords: situational resource planning; portrait of situation; online service; mandatory and orienting rules; linear problem of resource allocation; target displacement of solution; budget planning; priorities of expense items; interval cost planning
|Phone of the Center: +7 (499) 135-62-60E-mail of the Center: firstname.lastname@example.org