Труды сотрудников ИВМ СО РАН

[Text] : статья / N.V. Erkaev, V.S. Semenov, H.K. Alexeev, H.K. Biernat // Physics of Plasmas. - 2001. - Vol. 8, № 11. - p. 4800-4811DOI 10.1063/1.1410112 . -
Аннотация: The reconnection rate is obtained for the simplest case of two-dimensional (2D) symmetric reconnection in an incompressible plasma. In the short note [Erkaev et al., Phys. Rev. Lett. 84, 1455 (2000)], the reconnection rate is found by matching the outer Petschek solution and the inner diffusion region solution. Here the details of the numerical simulation of the diffusion region are presented and the asymptotic procedure which is used for deriving the reconnection rate is described. The reconnection rate is obtained as a decreasing function of the diffusion region length. For a sufficiently large diffusion region scale, the reconnection rate becomes close to that obtained in the Sweet-Parker solution with the inverse square root dependence on the magnetic Reynolds number Re m , determined for the global size of the current sheet. On the other hand, for a small diffusion region length scale, the reconnection rate turns out to be very similar to that obtained in the Petschek model with a logarithmic dependence on the magnetic Reynolds number Re m . This means that the Petschek regime seems to be possible only in the case of a strongly localized conductivity corresponding to a small scale of the diffusion region. c 2001 American Institute of Physics.

http://icm.krasn.ru/refextra.php?id=1805,
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ИВМ СО РАН : 660036, Красноярск, Академгородок, 50, стр.44

Доп.точки доступа:
Semenov, V.S.; Семенов В.С.; Alexeev, H.K.; Алексеев Г.К.; Biernat, H.K.; Еркаев, Николай Васильевич

[Текст]. - Электрон. дан. (128 Кб)
. - Режим доступа: http://icm.krasn.ru/refextra.php?id=2083. - Электрон. версия печ. публикации . - Режим доступа: http://library.krasn.ru/trudy/1998/2083gorban_98SOROS.pdf (Полный текст) : статья / А.Н. Горбань. - Электрон. дан. (128 Кб) // Соросовский образовательный журнал. - 1998. - № 12. - С. 105-112
Аннотация: Обсуждается представление функций многих переменных с помощью функций одного переменного. Дано введение в теорию искусственных нейронных сетей. Показано, что с помощью нейросетей можно сколь угодно точно вычислить любую непрерывную функцию.
The following problems on the representation of function of multiple variables by means of simpler functions are discussed: are there functions of multiple variables which cannot be exactly represented by means of functions of one variable and when is an approximate representation of functions using simpler functions possible? An introduction to the theory of artificial neural networks is given. It is shown that with the aid of neural networks one can arbitrarily calculate precisely any continuous function.

http://icm.krasn.ru/refextra.php?id=2083,
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ИВМ СО РАН : 660036, Красноярск, Академгородок, 50, стр.44

Доп.точки доступа:
Gorban A.N.

[Electronic resource]. - Electronic data (232 Kb) : статья / A.N. Gorban, Y.I. Shokin, V.I. Verbitskii. - Electronic data (232 Kb) // arXiv:physics/9702021 . - 1997
   Перевод заглавия: Совместно диссипативные операторы и инфинитиземальный эффект Мура в интервальных пространствах
Аннотация: In solving a system of ordinary differential equations by an interval method the approximate solution at any considered moment of time t represents a set (called interval) containing the exact solution at the moment t. The intervals determining the solution of a system are often expanded in the course of time irrespective of the method and step used. ??The phenomenon of interval expansion, called the Moore sweep effect, essentially decreases the efficiency of interval methods. In the present work the notions of the interval and the Moore effect are formalized and the Infinitesimal Moore Effect (IME) is studied for autonomous systems on positively invariant convex compact. With IME the intervals expand along any trajectory for any small step, and that means that when solving a system by a stepwise interval numerical method with any small step the interval expansion takes place for any initial data irrespective of the applied method. The local conditions of absence of IME in terms of Jacoby matrices field of the system are obtained. The relation between the absence of IME and simultaneous dissipativity of the Jacoby matrices is established, and some sufficient conditions of simultaneous dissipativity are obtained. (The family of linear operators is simultaneously dissipative, if there exists a norm relative to which all the operators are dissipative.)??

http://icm.krasn.ru/refextra.php?id=2093,
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ИВМ СО РАН : 660036, Красноярск, Академгородок, 50, стр.44

Доп.точки доступа:
Shokin, Y.I.; Шокин, Юрий Иванович; Verbitskii, V.I.; Вербицкий В.И.; Горбань, Александр Николаевич

[Text] : статья / A.N. Gorban, V.I. Bykov, G.S. Yablonskii // Chemical Engineering Science. - 1986. - Vol. 41, № 11. - P2739-2745
   Перевод заглавия: Аналог термодинамических функций для реакций без взаимодействия различных веществ

ГРНТИ

31.15.25

Аннотация: Function similar to Lyapunov's function has been constructed for reactions with ?i Ai ?j ?j Aj stages. This provides for the quasi-thermodynamics of the appropriate kinetic model, which implies steady-state uniqueness and global stability in the reaction polyhedron. The kinetic law generalizing the Marcelin -de Donder kinetics has been written for a separate stage. Explicit Lyapunov thermodynamic functions have been written for various conditions of the reaction proceeding in closed systems. The matrix of linear approximation close to equilibrium is expressed by means of the introduced scalar product. Particularly, the absence of damped oscillations as equilibrium is approached as shown.

http://icm.krasn.ru/refextra.php?id=2098,
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ИВМ СО РАН : 660036, Красноярск, Академгородок, 50, стр.44

Доп.точки доступа:
Bykov, V.I.; Быков, Валерий Иванович; Yablonskii, G.S.; Яблонский, Григорий Семенович; Горбань, Александр Николаевич

[Текст] : статья / A.E. Novikov, E.A. Novikov // Вестник СибГАУ. - 2009. - Вып. 5(26). - С. 17-20
Аннотация: An algorithm of right-hand side and Jacobian formation of differential equations of chemical kinetics is described. Numerical simulation of the cesium cycle in the upper atmosphere is conducted by means of the L-stable method of the second order of accuracy with the control accuracy. The results of the computation are presented.

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Доп.точки доступа:
Novikov, E.A.; Новиков, Евгений Александрович

/ A. Divin [et al.] // J. Geophys. Res-Space Phys. - 2012. - Vol. 117. - Ст. A06217, DOI 10.1029/2011JA017464. - Cited References: 43. - The present work is supported partially by the Onderzoekfonds KU Leuven (Research Fund KU Leuven), by the NASA MMS grant NNX08AO84G and by the European Commission's Seventh Framework Programme (FP7/2007-2013) under the grant agreement 263340 (SWIFF project, www. swiff. eu) and 269198 - Geoplasmas (Marie Curie International Research Staff Exchange Scheme). Additional support is provided by RFBR grants 09-05-91000-ANF-a, 12-05-00152-a and 12-05-00918-a, Austrian Science Fund project T193-N16 and by SPSU grants 11.38.47.2011 and 11.38.84.2012. The simulations were conducted on the resources of the Vlaams Supercomputer Centrum (VSC) at the Katholieke Universiteit Leuven. The authors wish to thank the reviewers for their comments that helped to improve the manuscript. . - ISSN 2169-9380РУБ Astronomy & Astrophysics

Аннотация: The Sweet-Parker analysis of the inner electron diffusion region of collisionless magnetic reconnection is presented. The study includes charged particles motion near the X-line and an appropriate approximation of the off-diagonal term for the electron pressure tensor. The obtained scaling shows that the width of the inner electron diffusion region is equal to the electron inertial length, and that electrons are accelerated up to the electron Alfven velocity in X-line direction. The estimated effective plasma conductivity is based on the electron gyrofrequency rather than the binary collision frequency, and gives the extreme (minimal) value of the plasma conductivity similar to Bohm diffusion. The scaling properties are verified by means of Particle-in-Cell simulations. An ad hoc parameter needs to be introduced to the scaling relations in order to better match the theory and simulations.


Доп.точки доступа:
Divin, A.; Lapenta, G.; Markidis, S.; Semenov, V.S.; Erkaev, N.V.; Еркаев, Николай Васильевич; Korovinskiy, D.B.; Biernat, H.K.

[Text] / A. P. Gavrilyuk, N. Y. Shaparev // Quantum Electron. - 2013. - Vol. 43, Is. 10. - P943-948, DOI 10.1070/QE2013v043n10ABEH015141. - Cited References: 18 . - ISSN 1063-7818РУБ Engineering, Electrical & Electronic + Physics, Applied

Аннотация: By means of numerical modelling of the combined effect of laser (1.06 mu m) and microwave (10(10)-10(13) s(-1)) radiation on the aluminium surface in vacuum it is shown that the additional action of microwave radiation with the frequency 10(12) s(-1) provides complete ionisation of the metal vapour (for the values of laser radiation duration and intensity used in the calculations), while in the absence of microwave radiation the vapour remains weakly ionised. The mathematical model used accounts for the processes, occurring in the condensed phase (heat conduction, melting), the evaporation and the kinetic processes in the resulting vapour.


Доп.точки доступа:
Shaparev, N.Ya.; Шапарев, Николай Якимович; Гаврилюк, Анатолий Петрович

/ O. V. Sadovskaya // Proceedings of XLI International Summer School–Conference APM 2013. - 2013. - P484-491
Аннотация: Mathematical model for the description of deformation of a porous metal is constructed on the basis of generalized rheological method. In this method a new rheological element, so-called rigid contact, is used to describe the uniaxial deformation of materials with different resistance to tension and compression. Change in the resistance of a porous metal to external loads, when the collapse of pores occurs, is taken into account by means of the von Mises–Schleicher strength condition. Irreversible deformation is described with the help of yield condition, modeling the plastic loss of stability of porous skeleton. For a homogeneous porous medium the fields of displacements and stresses in the problem of radial expansion of spherical and cylindrical cavities under the action of internal pressure considering the effect of collapse of pores are constructed in closed form. The algorithm of numerical realization of the model of dynamic deformation of metal foams on multiprocessor computer systems of the cluster type is worked out

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ИВМ СО РАН : 660036, Красноярск, Академгородок, 50, стр.44

Доп.точки доступа:
Садовская, Оксана Викторовна

[Текст] : статья / V. M. Sadovskii, O. V. Sadovskaya, K. S. Svobodina // Journal of Siberian Federal University. Mathematics & Physics. - 2013. - Vol. 6, Iss. 3. - p. 342-348
   Перевод заглавия: Анализ дисперсии гидроакустических волн на основе модели вязкоупругой среды
Аннотация: On the basis of mathematical model of the Poynting–Thomson viscoelastic medium the effect of acoustic dispersion of water is described: the phase velocity of waves of terahertz frequency is doubled in comparison with the velocity of waves of sound range. Rheological parameters of the model are selected by means of the values of the velocities of propagation of slow and fast monochromatic waves. The system of equations of the dynamics of the Poynting–Thomson viscoelastic medium is reduced to the form, hyperbolic by Friedrichs. It guarantees the correctness of the Cauchy problem and boundary value problems with dissipative boundary conditions, and also allows to use the monotone grid-characteristic schemes for numerical solution of problems. In the framework of 1D model the computations of a transformation of hydroacoustic waves, generated by U-shaped impulse of pressure, were performed. Results of computations show a strong damping of the fast precursor as it passes the distance of hundred nanometers from the moment of entry and the emergence of stable profile of the slow wave at the mesolevel.

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Доп.точки доступа:
Sadovskaya, O.V.; Садовская, Оксана Викторовна; Svobodina, K.S.; Садовский, Владимир Михайлович

[Text] / V. V. Denisenko [et al.] // Ann. Geophys. - 2008. - Vol. 26, Is. 8. - P2111-2130. - Cited References: 19. - This work is supported by grant 07-05-00135 from the Russian Foundation for Basic Research, by the Programs 16.3 and 2.16 of the Russian Academy of Sciences, and by project I.2/04 from "Osterreichischer Austauschdienst". It is also supported by the Austrian "Fonds zur Forderung der wissenschaftlichen Forschung" under projects P17100-N08 and P20145-N16. We acknowledge support by the Austrian Academy of Sciences, "Verwaltungstelle fur Auslandsbeziehungen", and the Russian Academy of Sciences. . - ISSN 0992-7689РУБ Astronomy & Astrophysics + Geosciences, Multidisciplinary + Meteorology & Atmospheric Sciences

Аннотация: A quantitative division of the ionosphere into dynamo and motor regions is performed on the base of empirical models of space distributions of ionospheric parameters. Pedersen and Hall conductivities are modified to represent an impact of acceleration of the medium because of Ampere's force. It is shown that the currents in the F(2) layer are greatly reduced for processes of a few hours duration. This reduction is in particular important for the night-side low-latitude ionosphere. The International Reference Ionosphere model is used to analyze the effect quantitatively. This model gives a second high conducting layer in the night-side low-latitude ionosphere that reduces the electric field and equatorial electrojets, but intensifies night-side currents during the short-term events. These currents occupy regions which are much wider than those of equatorial electrojets. It is demonstrated that the parameter sigma(d)=sigma(P)+sigma(H)Sigma(H)/Sigma(P) that involves the integral Pedersen and Hall conductances Sigma(P), Sigma(H) ought to be used instead of the local Cowling conductivity sigma C in calculations of the electric current density in the equatorial ionosphere. We may note that Gurevich et al. (1976) derived a parameter similar to sigma(d) for more general conditions as those which we discuss in this paper; a more detailed description of this point is given in Sect. 6. Both, sigma(d) and sigma(C), appear when a magnetic field line is near a nonconducting domain which means zero current through the boundary of this domain. The main difference between sigma(d) and sigma(C) is that sigma d definition includes the possibility for the electric current to flow along a magnetic field line in order to close all currents which go to this line from neighboring ones. The local Cowling conductivity sigma(C) corresponds to the current closure at each point of a magnetic field line. It is adequate only for a magnetic field line with constant local conductivity at the whole line when field-aligned currents do not exist because of symmetry, but sigma(C)=sigma(d) in this case. So, there is no reason to use the local Cowling conductivity while the Cowling conductance Sigma(C)=Sigma(P)+Sigma(2)(H)/Sigma(P) is a useful and well defined parameter.


Доп.точки доступа:
Denisenko, V.V.; Денисенко, Валерий Васильевич; Biernat, H.K.; Mezentsev, A.V.; Shaidurov, V.A.; Zamay, S.S.

[Text] / L. V. Gileva, V. V. Shaidurov // Russ. J. Numer. Anal. Math. Model. - 2009. - Vol. 24, Is. 5. - P425-438, DOI 10.1515/RJNAMM.2009.027. - Cited References: 11. - This analysis was partially supported by Grant 08-01-00621 of the Russian Foundation of Basic Research. . - ISSN 0927-6467РУБ Engineering, Multidisciplinary + Mathematics, Applied

Аннотация: In this paper, a full multigrid algorithm with a symmetric V-cycle for a grid problem obtained by discretization of a second-order elliptic equation with quadratic finite elements on triangles is studied. The multigrid complexity of the algorithm is proved. This means that the number of arithmetic operations required to achieve the order of accuracy of an approximate solution equal to that of the discretization error linearly depends on the number of unknowns. The rate of convergence is found to be higher than that for linear finite elements in spite of the higher order of accuracy.


Доп.точки доступа:
Shaidurov, V.V.; Шайдуров, Владимир Викторович; Гилева, Лидия Викторовна; Russian Foundation [08-01-00621]

[Text] : статья / Y. Gaponenko, A. Mialdun, V. Shevtsova // International Journal of Multiphase Flow. - 2012. - Vol. 39. - p. 205-215, DOI 10.1007/s12217-008-9075-7 . - ISSN 0938-0108
Аннотация: Experiments and numerical simulations were carried out for shear-driven two-phase flows in a confined volume of liquid under conditions of normal gravity. The geometry corresponds to a cylindrical liquid bridge surrounded by a concentric annular gas channel with external solid walls. The internal part consists of solid supports at the bottom and top, while the central part is a liquid zone filled with a viscous liquid and kept in its position by surface tension. Gas enters into the annular duct, flows between solid walls and upon reaching the liquid zone entrains initially quiescent liquid. The flow dynamics is governed by the Navier–Stokes equations in both fluids, which are numerically solved in the exact experimental geometry taking into account interface deformation by gravity. In the experiments 5 cSt silicone oil and air were used as test fluids and the flow was monitored by means of particle tracking velocimetry. The experiments were performed for unit aspect ratio (the ratio of liquid zone length to its radius), while the simulations of shear-driven flow were carried out for a wide range of parameters. A particular attention is focused on the effect of free surface shape and fluids viscosity contrast on the interfacial flow dynamics. The current study suggests a linear dependence between velocities of gas and liquid when the viscosity of the liquid is larger by two orders of magnitude than that of gas. Another relation is proposed when the fluids viscosity ratio, μl/μg, is less than 50.

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Доп.точки доступа:
Mialdun, A.; Shevtsova, V.; Гапоненко, Юрий Анатольевич

[Text] : статья / A. N. Gorban, G. S. Yablonskii // Chemical Engineering Science. - 2011. - Vol. 66, Iss. 21. - p. 5388-5399DOI 10.1016/j.ces.2011.07.054 . -
Аннотация: The principle of detailed balance states that in equilibrium each elementary process is equilibrated by its reverse process. For many real physico-chemical complex systems (e.g. homogeneous combustion, heterogeneous catalytic oxidation, most enzyme reactions, etc.), detailed mechanisms include both reversible and irreversible reactions. In this case, the principle of detailed balance cannot be applied directly. We represent irreversible reactions as limits of reversible steps and obtain the principle of detailed balance for complex mechanisms with some irreversible elementary processes. We prove two consequences of the detailed balance for these mechanisms: the structural condition and the algebraic condition that form together the extended form of detailed balance. The algebraic condition is the principle of detailed balance for the reversible part. The structural condition is the convex hull of the stoichiometric vectors of the irreversible reactions has empty intersection with the linear span of the stoichiometric vectors of the reversible reactions. Physically, this means that the irreversible reactions cannot be included in oriented cyclic pathways. The systems with the extended form of detailed balance are also the limits of the reversible systems with detailed balance when some of the equilibrium concentrations (or activities) tend to zero. Surprisingly, the structure of the limit reaction mechanism crucially depends on the relative speeds of this tendency to zero.

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Доп.точки доступа:
Yablonskii, G.S.; Горбань, Александр Николаевич

/ N. A. Makhutov, I. I. Koksharov, A. M. Lepikhin // Strength of Materials. - 1992. - Vol. 23, Is. 5. - P481-488, DOI 10.1007/BF00771443 . - ISSN 0039-2316
Аннотация: Methods used to calculate the reliability indices of structural components (the distribution function of remaining life, the probability of failure-free service, and the risk function) as applies to problems of the propagation of defects under a cyclic load are examined. The potentials of the method of "numeric experiments" are demonstrated in an example of the calculation of crack kinetics in a branch pipe in tension with bending. The reliability indices are calculated for a plane element with a crack by means of numeric integration of determining equations. It is possible to solve problems with different laws governing crack propagation and forms of density distribution for the size of the initial defect within the framework of these methods. A combination of approaches of fracture mechanics and reliability theory with numeric methods of calculation make it possible to evaluate the reliability indices of a defective structural component. В© 1992 Plenum Publishing Corporation.

Scopus

Держатели документа:
A. A. Blagonravov Institute of Machinery, Academy of Sciences of the USSR, Moscow, Russian Federation
Computer Center, Siberian Branch, Academy of Sciences of the USSR, Krasnoyarsk, Russian Federation
ИВМ СО РАН

Доп.точки доступа:
Makhutov, N.A.; Махутов, Николай Андреевич; Koksharov, I.I.; Кокшаров, Игорь Ильич; Lepikhin, A.M.; Лепихин, Анатолий Михайлович

[Text] / S. P. Sharyi // J. Comput. Syst. Sci. Int. - 1997. - Vol. 36, Is. 3. - P378-387. - Cited References: 22 . - ISSN 1064-2307РУБ Computer Science, Artificial Intelligence + Computer Science, Cybernetics + Computer Science, Theory & Methods

Аннотация: This paper deals with mathematical and computational aspects of analysis of a linear static system under conditions of interval uncertainty. In particular, we consider minmax problems of estimating states (inverse minmax problems) under various assumptions on the realization of the system. The notion of alpha beta-solutions of interval equations is introduced as a formalization of the mathematical statement of the problem. The main result of the paper is a new algebraic approach to internal algebraic estimation of alpha beta-solution sets of interval linear equations, whose mathematical basis is the substitution of the initial problem for the problem of finding the algebraic solution of an auxiliary system of equations in extended Kaucher arithmetic. The property of maximality by inclusion of interval solutions of the problem, which are obtained by means of the algebraic approach, is proved.

WOS,
Scopus

Держатели документа:
Computer Center, Russian Academy of Sciences, Krasnoyarsk, Russian Federation
ИВМ СО РАН

Доп.точки доступа:
Sharyi, S.P.; Шарый С.П.

/ S. P. Sharyj // Izvestiya Akademii Nauk. Teoriya i Sistemy Upravleniya. - 1997. - Is. 3. - P51-61 . - ISSN 0002-3388
Аннотация: The paper is devoted to mathematical and computer aspects of the static linear system analysis under conditions of interval uncertainty. The main result of the paper is a new algebraic approach to internal estimation of ?? sets of solutions of interval linear equations. The maximality property of inclusion of the interval solutions, obtained by means of the algebraic approach, is proved.

Scopus

Держатели документа:
VTs RAN, Krasnoyarsk, Russian Federation
ИВМ СО РАН

Доп.точки доступа:
Sharyj, S.P.; Шарый С.П.

[Text] / A. N. Gorban, D. C. Wunsch // IEEE WORLD CONGRESS ON COMPUTATIONAL INTELLIGENCE : IEEE, 1998. - 2nd IEEE World Congress on Computational Intelligence (WCCI 98) (MAY 04-09, 1998, ANCHORAGE, AK). - P1271-1274. - Cited References: 0 . - ISBN 0-7803-4860-5РУБ Computer Science, Artificial Intelligence + Computer Science, Interdisciplinary Applications + Engineering, Biomedical + Engineering, Electrical & Electronic + Medical Informatics + Neurosciences

Аннотация: A general approximation theorem is proved. It uniformly envelopes both the classical Stone theorem and approximation of functions of several variables by means of superpositions and linear combinations of functions of one variable. This theorem is interpreted asa statement on universal approximating possibilities ("approximating omnipotence") of arbitrary nonlinearity. For the neural networks, our result states that the function of neuron activation must be nonlinear - and nothing else.

WOS

Держатели документа:
Russian Acad Sci, Krasnoyarsk Comp Ctr, Siberian Branch, Krasnoyarsk 660036 36, Russia
ИВМ СО РАН

Доп.точки доступа:
Gorban, A.N.; Горбань, Александр Николаевич; Wunsch, D.C.

[Text] / O. V. Sadovskaya, V. M. Sadovskii, M. P. Varygina // ECCOMAS Thematic Conference - COMPDYN 2013: 4th International Conference on Computational Methods in Structural Dynamics and Earthquake Engineering, Proceedings - An IACM Special Interest Conference. - 2013. - P4578-4592
Аннотация: In the framework of mathematical model of a block medium with elastic blocks interacting through compliant viscoelastic interlayers and its approximation on the basis of equations of the Cosserat continuum, the problems of periodic perturbation of a layer and of a half-space under the action of distributed and localized surface loads are solved numerically. The simple formulas are suggested to determine the elasticity coefficients of the moment continuum by given characteristics of the materials of blocks and interlayers, which provide a good correspondence of the wave fields received by means of the exact and approximate models. Parallel computational algorithms, based on models of the inhomogeneous elasticity theory and the Cosserat elasticity theory, are applied to the analysis of propagation of elastic waves in geomaterials with layered and block microstructure. These algorithms are realized as parallel program systems for GPUs (using CUDA technology) and for multiprocessor computers of the cluster type (using MPI library). Monotone grid-characteristic schemes with a balanced number of time steps in elastic layers or blocks and in viscoelastic interlayers are used. By the analysis of numerical solutions it is shown that the multiblock medium has a resonant frequency of rotational motion of blocks, and this frequency does not depend on the size of a massif and on the boundary conditions at its surface.

Scopus,
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Доп.точки доступа:
Sadovskii, V.M.; Садовский, Владимир Михайлович; Varygina, M.P.; Варыгина, Мария Петровна; Садовская, Оксана Викторовна

[Text] / V. M. Sadovskii, O. V. Sadovskaya // ECCOMAS Thematic Conference - COMPDYN 2013: 4th International Conference on Computational Methods in Structural Dynamics and Earthquake Engineering, Proceedings - An IACM Special Interest Conference. - 2013. - P4277-4286
Аннотация: Mathematical model for the description of deformation of a porous material with a random distribution of pores is constructed on the basis of generalized rheological method taking into account the different resistance of a material to tension and compression. Phenomenological parameters of the model are determined by means of the approximate computations for the problem of static loading of a cubic periodicity cell with spherical cavities. Within the framework of this theory the fields of displacements and stresses around expanding cavity of spherical shape in a homogenious space are constructed. It is shown that the porosity does not change at the stage of elastic deformation. When the pressure increases, a zone of plastic compaction is formed in the vicinity of a cavity, and in a part of this zone the collapse of pores takes place. Engineering formulas for calculation of critical pressures of the elastic limit state and the limit state of a medium with open pores, and also the formulas for determining the radiuses of interfaces of zones of plasticity and compaction are obtained. A complex of parallel programs for numerical analysis of the dynamic deformation of porous materials on multiprocessor computer systems is worked out. By means of this complex a series of computations for deformation of the protection elements, made of metal foams, under the action of localizedim pulsive loads was performed. The random nature of distribution of the pores size is taken into account with the help of computer modeling. Computations allow one to estimate plastic dissipative part of the energy of impact.

Scopus,
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Доп.точки доступа:
Sadovskaya, O.V.; Садовская, Оксана Викторовна; Садовский, Владимир Михайлович

[Текст] : статья / M. G. Sadovsky, M. Yu. Senashova // Journal of Siberian Federal University. Mathematics & Physics = Журнал Сибирского федерального университета. Математика и физика. - 2013. - Т. 6, № 1. - С. 105-113
   Перевод заглавия: Локальная информированность может приводить к хаотической миграции
Аннотация: A novel model of the targeted migration of a population separated into two subpopulations is proposed. The model is implemented for the local information access. Migration is not random and yields the maximization of a net reproduction, in general; specific version of this general rule is proposed. The local information access means the total lack of knowledge on the environmental conditions and transfer cost at the immigration station, for beings occupying the given station. Various regimes for the models are studied. A reciprocal chaotic-like migrations may take place, for some reasonable parameters figures.

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Держатели документа:
ИВМ СО РАН : 660036, Красноярск, Академгородок, 50, стр.44

Доп.точки доступа:
Senashova, M.Yu.; Сенашова, Мария Юрьевна; Садовский, Михаил Георгиевич