Software & Systems

Articles of journal № 2 at 2014 year.

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21. Quantum computing in intelligent robust control system design for 7 degrees of freedom redundant robot-manipulator [№2 за 2014 год]
Authors: Nikolaeva A.V., Barkhatova I.A., Ulyanov, S.V.
Visitors: 10414
The problems of designing control systems using soft and quantum computing on the example of complex con-trol object (redundant 7 degrees of freedom manipulator) are described. A self -organization strategy for a knowledge base of one-type fuzzy controllers using quantum computing technologies is considered. Application of intelligent computing and quantum self-organization algorithm allows reaching control purpose in unexpected situations. It it reached due to i mproving robustness level of intelligent control system in the problem-oriented field. An important result of intelligent control systems design is a possibility of implementing quantum algorithms and quantum computing in typical (not hybrid quantum) defau lt configuration hardware processor for robot manipulator as the control object. Quantum language description of most classical (semistructured and difficult to solve using classical logic) engineering tasks allows finding an effective solution. Positive re-sult of intelligent soft computing technologies application based on quantum computing toolkit led to a new alternative a p-proach. It is using intelligent quantum computing technologies in tasks of control optimization. The paper shows the efficiency of designed intelligent control systems using soft and quantum computing technologies. To estimate control systems work the authors introduce a set of performance criteria. This set is adjusted to concerned contr ol object (7 degrees of freedom robot manipulator) according to required accuracy characteristics. A particular focus is on robot manipulator behavior that is controlled by proposed intelligent control systems in une x-pected situations connected with internal noise in complex control object.

22. Metamonitoring system for high-performance computing environment [№2 за 2014 год]
Authors: Oparin G.A., Novopashin A.P., Sidorov I.A., Skorov V.V.
Visitors: 8866
The paper discusses an approach to the creation of metamonitoring system for high -performance computing environ-ment intended to solve resource-intensive tasks, and including a lot o f loosely-coupled multivendor computing resources. The basic purpose of this system is to provide the operator of a computing environment with structured and relevant information about a ny computing node status (CPU time usage, RAM, IO -system, network usage, etc.), current equipment state, values of the sensors (tem-perature of processors and motherboards, room temperature), engineering infrastructure devices status and others. The princip al dis-tinctive feature and novelty aspect of the developed metamonitor ing system includes creation of the universal software agents cap a-ble to collect data about state of different environment components from local monitoring systems, to unify and analyze these data, and if necessary to generate and execute automatic control actions directed on changing equipment working mode, including the shutdown in case of emergencies. Each agent of the meta -monitoring system is implemented on the same principles and includes fol-lowing subsystems: data collecting subsystem, database subsy stem, expert subsystem, and control subsystem. The approach is based on web-technologies and multi-agent technologies usage, methods of expert systems creation, methods of decentralized processing and the distributed storage of data. The developed system was successfully approved in the Supercomputer Center of ISDCT SB of the Russian Academy of Sciences.

23. The method of quality factors estimation for radar detection [№2 за 2014 год]
Authors: Platonov A.Yu., Pomazuev O.N., Mironov A.M., Abu-Abed, F.N., Ryumshin A.R.
Visitors: 14566
Nowadays stealth technologies are widely used. That is why the radiated radar -tracking signal is essentially r e-flected and absorbed. Thus, the power of a reflected signal on an intake radar entry is decreased. It complicates airplane d e-tection, or other object creat ed according to similar technology. Under these conditions it is difficult to estimate quality fa c-tors of radar detection of stealth and small targets. In many cases the radar signals amplitude and a phase is unknown parametres. The models of signals are u sed often when there are fast (in relation to clock frequency) fluctuations amplitude signals and a phase when there is no possibility to es ti-mate their values according to the results of preliminary statistical estimation on the previous intervals. We propose a technique which allows determining the quality of radar detection for a wide class of models of signals (i n-cluding stealth and small targets) in terms of stationary Gaussian noise, impulse noise and in non -jamming environment. The technique uses the obtained analytical expressions and approximation of distributions with Gram–Charlier series in Edge-worth Expansion. Detection threshold for given probabilities of false alarm is defined by Newton's method. It improves the accuracy and simplifies the calculations. The article shows the estimates for quality detection under these conditions. The de-veloped methodology and the resulting estimates can be used to determine quality factors of higher hierarchical level sys-tems. For example, indicators of secondar y signal processing, probability of signal detection (capture) in the search area.

24. The software-programmable method of interchannel gradient reconstruction of color digital images [№2 за 2014 год]
Authors: Samoylin E.A., Shipko V.V.
Visitors: 6419
The article considers a reconstruction method of failure elements of the color digital image using interchannel redunancy. Nowadays there are vectorial median filters that show their advantage comparing to traditional component -wise image processing. At the same time they aren’t able to de -update lost signal value always authentically because of the limited aperture sample capture, and also in case of overwhelming quantity of faulty elements in an aperture. Meanwhile, redunancy appearing after transition from gray-scale to color images opens new opportunities for restoration of images signals values lost due to interference attack. In particular, in case of distortion of image element brightness in one of color channels, it is possible to evaluate its value using the brightness amplitude of other color channels appropriate elements. The local gradien ts are the difference between the central aperture element and closely-spaced elements. The base of the method is an assump-tion that the local gradients are approximately equal in the image plane of each component. The results showed that this a s-sumption is fair for many real color digital images.The results of modeling show the superiority of interelement gradient r e-construction over median filtering in reconstruction accuracy of the lost or distorted elements of color image components. The results show that the offered method allows receiving higher accuracy of distorted signals restoration comparing to tradi-tional vectorial median processing. The example of the processing the real color digital image shows the efficiency of the presented method. The study results show the possibility to reconstruct interference signals of color digital images using local gradients of nearby channels. The proposed method implies the software implementation and can be used in different co m-puter systems and independent software modules for color digital images processing.

25. On some inverse spectral problems for an arbitrary perturbation of the bi-harmonic operator with singular coefficients [№2 за 2014 год]
Author: Serov V.S.
Visitors: 5671
The classical inverse boundary spectral problem for any perturbation of the bi -harmonic operator with singular coefficients from some Sobolev spaces is considered. The problem is formulated as follows: Do the Dirichlet eigenvalues and some derivatives of the corresponding normalized eigenfunctions at the boundary of smooth bounded domai n uniquely determine the coefficients of this operator? We proved the first step of this problem, i.e. we proved that the Dirichlet eigenvalues and the derivatives up to the second order of the normalized eigenfunctions at the boundary uniquely determine t he so-called Dirichlet-to-Neumann map that corresponds to the Friedrichs self-adjoint extension of any perturbation of the bi-harmonic operator with singular coefficients. The main role in this proof is played by the existence of the Green’s function and its estimates up to the boundary of the domain. These facts will allow us to prove the classical Borg-Levinson theorem for the operators of fourth order of such type.

26. Mathematical model for ship life cycle milestones cost assessment through information support systems [№2 за 2014 год]
Author: Tretyakov O.V.
Visitors: 12648
The programming stage plays the most significant role in ship design and construction because the whole range of activities at design and construction stages is carried out for this stage exactly. In conjunction with future opera tional processes design, their cost is defined, and different kinds of resources are planned in the budget. Mistakes in resource for e-casting may lead to funding shortages, failures to support ship readiness at a certain level and decrease the Navy operationa l potential. Conventional techniques for cost evaluation of separate stages of the ship life cycle are based on statistic relations. Such an approach requires regular technique and data updates according to ship design and operation findings. It is not a l-ways possible, especially when new ships operation experience is absent. Furthermore, it is quite challenging to assess (with acceptable error) the impact of ground-breaking decisions taken during ship design and construction on its operational cost using such techniques. The article describes a mathematical model of ship life cycle cost assessment based on activity-based costing analysis. The proposed approach not only enables to assess the ship cost based on the tasks cost, but also reveal the most vulnerable points in making design decisions. The model and its technique are designed for developing the ship life c y-cle information support system. The ship's structural and functional model is an information resource for calculations. And this model is based on the ship general digital model. This is one of the peculiarities of the said approach for cost assessment.

27. Computer control principles based on user emotional state assessment [№2 за 2014 год]
Authors: Turovskiy Ya.A., Kurgalin S.D.
Visitors: 7877
The paper researches the possibility of using an additional channel of human-computer communication. It is based on the application of functional stress assessment and/or emotional state of a user to optimize the computer control. This assessment allows implementing several strategies of computer control. The user chooses a control channel or a comb i-nation of channels. When the user’s status indicators for this channel are in a state of a rest, the operating system control s the processes priorities based on current tasks. If the user status indicators reflect stress, management of the processes priorities is carried out using computer resources reallocation for programs and processes needed for the user now. If the user uses co m-puter games or multimedia applications, then some components selected by the user are changed according to user-defined settings and his status. Such components as: the state of a "hero" in computer games, games soundtrack and/or the theme accompanying the user’s work, colors of the games and/or colors of a number of elements designed for working with the oper a-tion system (a type and a status of the interface, including graphics). The authors conclude that the use of a proposed "em o-tional channel" to control the computer, in addition to the existing control ones, will significantly increase the efficiency of its work. It also will reduce the time of waiting for the user tasks completion by the operation system, will optimize the multi-media applications functioning, will bring new opportunities to interact with the operation system, will expand the "hero" functionality in the computer games, etc. Further this will provide the introduction of context -oriented interaction elements into the computer control systems, or, in general, into the information and communication technologies.

28. Modeling of the deformation process in the presence of a phase transition from a potential to dissipative stream [№2 за 2014 год]
Authors: Федотов В.П., Gorshkov A.V.
Visitors: 6133
The paper considers the algorithm for solving nonlinear elasticity issue. Cross-effect in complex systems is determined by the phenomenological components of relevant systems of equations. In these systems the relation between the generalized flows and generalized forces is established based on the Onsa ger’s ap-proach. For the deformation problems, this relation usually is established by Hook’s linear postulate. However, this postulat e can not be a basis for describing the second-kind phase transition from elasticity to dissipative plastic flow. And relating con-tinuous physical quantities (temperature, admixture concentration etc.) can not offset yield strength since the latter is an ex-perimental pointwise quantity. As a practically confirmed hypothesis, it is assumed that the reciprocity factors L km, constant by Onsager, can be nonline-ar functions. For deformation problems we use the Cauchy postulate. It states that the Onsager factor in the elastic region i s a quadratic function of strain. In this case the elasticity problem solution is reduced to the sol ution of nonlinear equation. The application of the finite elements method requires a solution of large -dimension systems and, consequently, it is extremely time-consuming. To reduce the computation time, the boundary element method is used in combination with analytical com-putation if possible. The article considers the example of the algorithm application to solve a nonlinear plane problem of el as-ticity for an inhomogeneous region.

29. Modeling dynamic problems of thin-walled framework [№2 за 2014 год]
Author: Chernov S.A.
Visitors: 9347
The article describes the flexural and torsional vibrations of an open profile thin -walled rod with one cross section symmetry axis. When solving the rod vibrations problem the static task is considered with the addition of inertia forces, i.e . using the principle of Dalembert. The weight and stiffness of the rod are accepted as constant. Based on energy relatios the mass matrices are obtained in the explicit form of thin-walled rod finite elements that are in bending and torsion, and also a spatial finite element. The article shows comparative calculations on free and forced vibrations of П-shaped frame that is formed of rolled channel and double tee. The frame model uses beam finite and thin -walled rod elements, i.e., the flexural form of vibrations without considering torsion-al inertia of the rods and the torsional vibrations form respectively. There are values of the lower frequencies and corresponding modes from frames plane in the beam-column joint with free vibrations, as well as the maximum normal stresses in the profilecross -sections. The method of modeling is implemented in applications computer programs.

30. Transductive learning logistic regression for the text classification problem [№2 за 2014 год]
Authors: Shagraev A.G., Bocharov I.A., Falk V.N.
Visitors: 12728
In many classification problems there are difficulties with obtaining sufficient amount of labeled documents for train set. At the same time, usually we have many unlabeled documents. This paper describes how to increase the quality of classifier predictions when having relatively small train set in comparison with test set. Non-standard method of forming feature vectors for natural language texts, using peculiar properties of news articles, is described. The paper also describes modifications of a classical linear classifier (logistic regression). We use a modification of st o-chastic gradient descent in order to optimize classifier’s parameters. In addition, we use modified loss functional (enlargin g the margin between classes) to train logistic regression. Apart from that, we suggest original method of transductive learning for logistic regression classifier. To perform transductive learning we define quality functional for unlabeled documents which helps to in crease classification recall sig-nificantly. To test implemented modifications of logistic regression we use “inverse” cross -validation technique. Experi-mental results from using implemented modifications make the positive impact of authors’ modifications of logistic regres-sion classifier and transductive learning on classification quality obvious.

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