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   K21

    Dynamic correction to moment approximations
[Text]. - Electronic data (45 Kb)
. - Режим доступа: http://icm.krasn.ru/refextra.php?id=2110. - Электрон. версия печ. публикации . - Режим доступа: http://library.krasn.ru/trudy/1998/2110gorban_PREMomMIM98.pdf (Полный текст) : статья / I.V. Karlin, A.N. Gorban, G. Dukek, T.F. Nonnenmacher. - Electronic data (45 Kb) // Physical review E. - 1998. - Vol. 57, № 2. - p. 1668-1672
   Перевод заглавия: Динамические поправки к моментным приближениям

Аннотация: Considering the Grad moment ansatz as a suitable first approximation to a closed finite-moment dynamics, the correction is derived from the Boltzmann equation. The correction consists of two parts, local and nonlocal. Locally corrected thirteen-moment equations are demonstrated to contain exact transport coefficients. Equations resulting from the nonlocal correction give a microscopic justification to some phenomenological theories of extended hydrodynamics

http://icm.krasn.ru/refextra.php?id=2110,
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Держатели документа:
ИВМ СО РАН : 660036, Красноярск, Академгородок, 50, стр.44

Доп.точки доступа:
Gorban, A.N.; Горбань, Александр Николаевич; Dukek, G.; Nonnenmacher, T.F.; Карлин, Илья Вениаминович
   В3
   M66

    Numerical Simulation the Periodic Operating Regime of HRE with MHD Control
[Text]. - Electronic text data (73 Kb)
. - Режим доступа: http://icm.krasn.ru/refextra.php?id=1515. - Электрон. версия печ. публикации . - Режим доступа: http://library.krasn.ru/trudy/2000/1515lab23eng_28.pdf (Полный текст) : статья / A.N. Mierau, V.A. Derevyanko, A.N. Vasilyev. - Electronic text data (73 Kb) // X International Conference on the Methods of Aerophysical Research. - Novosibirsk, 2000. - Part III. - p. 143-149

Аннотация: Nowadays both in Russia and abroad active research has been conducted on developing perspective hypersonic aerospace aircraft. The developing of such aircraft would allow to essentially expand aircraft possibilities and to reduce delivery cost of goods to the near-earth orbit. In many countries of the world there are programs of creation of hypersonic aircraft such as: HOTOL in Great Britain, NASP in USA, HERMES in France. One of key while conducting these projects is the creation of a hypersonic ramjet engine having necessary propulsive, mass and dimensional characteristics with all altitude range and flight velocities of an aircraft. The basic difficulties, in development of such engine types are caused by substantial of deterioration of quality of fuel mixture with an oxidant under supersonic flow velocities in the combustion chamber, which results in decrease of an engine efficiency and deterioration of its propulsion. To increase the efficiency of HRE with the supersonic flow velocity in the combustion chamber the authors offered MHD control of gas flow in the channel HRE based on creation in a stream of local plasma areas with temperature 104 K interacting with an external magnetic field [1], [2]. The work presents investigation results for the structure of non-stationary gas-dynamic flow in the channel HRE with MHD - control. It also describes the calculation of propulsion performance characteristics of the given engine on the basis of mathematical simulation of processes, which take place in the channel of an engine. Thee work objective was the research of non-stationary periodic flow with heat application in the tract HRE with MHD - control on the basis of mathematical modeling of processes which take place in the channel of an engine and the calculation of propulsion performance characteristics of an engine. In the work the model HRE including the air intake, MHD - channel and nozzle was considered. The MHD - channel is made of two flat electrodes and sidewalls from a dielectric. The local constant flow heat permitting to create periodical local plasma areas (T- layer) is provided with the systems of initiation the constant magnetic field in the volume of the channel is ensured with an external magnetic system.

http://icm.krasn.ru/refextra.php?id=1515,
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ИВМ СО РАН : 660036, Красноярск, Академгородок, 50, стр.44

Доп.точки доступа:
Derevyanko, V.A.; Деревянко, Валерий Александрович; Vasilyev, A.N.; Васильев А.Н.

    Dynamic changes of optical characteristics of resonant domains in metal nanoparticle aggregates under pulsed laser fields
[Text] : статья / A.P. Gavrilyuk, S.V. Karpov // Applied Physics B: Lasers and Optics. - 2011. - p. 65-72DOI 10.1007/s00340-010-4180-x . -


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

Доп.точки доступа:
Karpov, S.V.; Гаврилюк, Анатолий Петрович

    Brownian dynamic of laser cooling and crystallization of electron-ion plasma
[Text] : статья / A.P. Gavrilyuk, I.L. Isaev [et al.] // Physical review E. - 2009. - Vol. 80, Iss. 5. - Ст. 056404. - p. 1-6 10.1103/PhysRevE.80.056404 . -


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

Доп.точки доступа:
Isaev, I.L.; Karpov, S.V.; Krasnov, I.V.; Краснов, Игорь Васильевич; Shaparev, N.Ya.; Шапарев, Николай Якимович; Гаврилюк, Анатолий Петрович

    Numerical solution of dynamic problems in couple-stressed continuum on multiprocessor computer systems
[Text] : статья / V.M. Sadovsky, O.V. Sadovskaya, M.P. Varygina // International Journal of Numerical Analysis and Modeling, Series B. - 2011. - № 2-3. - p. 215-230


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

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

    Моделирование динамического контактного взаимодействия упругопластических тел с использованием высокопроизводительных вычислений
[Электронный ресурс]
. - Режим доступа: http://library.krasn.ru/trudy/2011/O_Sadov_MIT.pdf (Полный текст). - Загл. с титул. экрана. - Режим доступа: http://conf.nsc.ru/files/conferences/MIT-2011/fulltext/48869/51220/O_Sadov_tez.pdf (Полный текст на сайте конференции) : доклад / О.В. Садовская // Математические и информационные технологии / MIT-2011. - 2011, № гос. регистрации 0321102644 . - ISBN 978-5-905569-02-9
   Перевод заглавия: Simulation of the dynamic contact interaction of elastic-plastic bodies using high-performance computing


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

Доп.точки доступа:
Sadovskaya O.V.; «Вычислительные и информационные технологии в науке, технике и образовании», Международная конференция(IX ; 27 августа - 5 сентября 2011 г. ; Врнячка Баня / Будва)

    Deep Solar Activity Minimum 2007-2009: Solar Wind Properties and Major Effects on the Terrestrial Magnetosphere
/ C. J. Farrugia [et al.] // Sol. Phys. - 2012. - Vol. 281, Is. 1. - pp. 461-489, DOI 10.1007/s11207-012-0119-1. - Cited References: 53 . - 29. - ISSN 0038-0938
РУБ Astronomy & Astrophysics

Аннотация: We discuss the temporal variations and frequency distributions of solar wind and interplanetary magnetic field parameters during the solar minimum of 2007-2009 from measurements returned by the IMPACT and PLASTIC instruments on STEREO-A. We find that the density and total field strength were significantly weaker than in the previous minimum. The Alfv,n Mach number was higher than typical. This reflects the weakness of magnetohydrodynamic (MHD) forces, and has a direct effect on the solar wind-magnetosphere interactions. We then discuss two major aspects that this weak solar activity had on the magnetosphere, using data from Wind and ground-based observations: i) the dayside contribution to the cross-polar cap potential (CPCP), and ii) the shapes of the magnetopause and bow shock. For i) we find a low interplanetary electric field of 1.3 +/- 0.9 mV m(-1) and a CPCP of 37.3 +/- 20.2 kV. The auroral activity is closely correlated to the prevalent stream-stream interactions. We suggest that the Alfven wave trains in the fast streams and Kelvin-Helmholtz instability were the predominant agents mediating the transfer of solar wind momentum and energy to the magnetosphere during this three-year period. For ii) we determine 328 magnetopause and 271 bow shock crossings made by Geotail, Cluster 1, and the THEMIS B and C spacecraft during a three-month interval when the daily averages of the magnetic and kinetic energy densities attained their lowest value during the three years under survey. We use the same numerical approach as in Fairfield's (J. Geophys. Res. 76, 7600, 1971) empirical model and compare our findings with three magnetopause models. The stand-off distance of the subsolar magnetopause and bow shock were 11.8 R-E and 14.35 R-E, respectively. When comparing with Fairfield's (1971) classic result, we find that the subsolar magnetosheath is thinner by similar to 1 R-E. This is mainly due to the low dynamic pressure which results in a sunward shift of the magnetopause. The magnetopause is more flared than in Fairfield's model. By contrast the bow shock is less flared, and the latter is the result of weaker MHD forces.

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Доп.точки доступа:
Farrugia, C.J.; Harris, B.; Leitner, M.; Mostl, C.; Galvin, A.B.; Simunac, K.D.C.; Torbert, R.B.; Temmer, M.B.; Veronig, A.M.; Erkaev, N.V.; Еркаев, Николай Васильевич; Szabo, A.; Ogilvie, K.W.; Luhmann, J.G.; Osherovich, V.A.

    Parallel Program Systems for Modeling Elastic-Plastic Waves in Structurally Inhomogeneous Materials
/ V. M. Sadovskii, O. V. Sadovskaya ; ed. by T.E.Simos [et al.] // NUMERICAL ANALYSIS AND APPLIED MATHEMATICS (ICNAAM 2012), VOLS A AND B. Ser. AIP Conference Proceedings : AMER INST PHYSICS, 2012. - Vol. 1479: International Conference of Numerical Analysis and Applied Mathematics (ICNAAM) (SEP 19-25, 2012, Kos, GREECE). - pp. 1611-1614, DOI 10.1063/1.4756474. - Cited References: 4 . - ISBN 0094-243X. - ISBN 978-0-7354-1091-6
РУБ Mathematics, Applied + Physics, Applied

Аннотация: Parallel program systems for numerical solution of 2D and 3D problems of the dynamics of deformable media with constitutive relationships of rather general form on the basis of universal mathematical model describing small strains of elastic, elastic-plastic and granular materials are worked out. Some computations of dynamic problems with and without taking into account the moment properties of a material were performed on supercomputers with cluster architecture.

РИНЦ


Доп.точки доступа:
Sadovskii, V.M.; Садовский, Владимир Михайлович; Sadovskaya, O.V.; Садовская, Оксана Викторовна; Simos, T.E. \ed.\; Psihoyios, G. \ed.\; Tsitouras, C. \ed.\

    Numerical solving dynamic problems of elastoplastic deformation of solids
[Text] / I. O. Bogulskii, Y. M. Volchkov // Numerical Analysis and Applications. - 2012. - Vol. 5, Is. 2. - pp. 124-128, DOI 10.1134/S1995423912020048 . - ISSN 1995-4239
Аннотация: Numerical schemes for solving two-dimensional dynamic problems of elasticity theory based upon several local approximations for each of the required functions are discussed. The schemes contain free parameters (dissipation constants). An explicit form of artificial dissipation of the solutions allows us to control its size and to effectively construct both explicit and implicit schemes. The principle of producing such schemes is applied to a plane dynamic problem of elasticity theory as an example. We describe a class of problems for which numerical algorithms using several local approximations for each of the required functions are constructed. Examples of solving practical problems are given. В© 2012 Pleiades Publishing, Ltd.

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Доп.точки доступа:
Bogulskii, I.O.; Богульский, Игорь Олегович; Volchkov, Y.M.

    Challenges and opportunities for integrating lake ecosystem modelling approaches
[Text] / W.M. Mooij [et al.] // Aquat. Ecol. - 2010. - Vol. 44, Is. 3. - pp. 633-667, DOI 10.1007/s10452-010-9339-3. - Cited References: 260. - WM, RG, IP, SG, PV and AD were supported by grant 047.017.012 of the Netherlands Organization for Scientific Research (NWO) and the Russian Foundation for Basic Research (RFBR). LDSD was supported by NWO grant 817.01.007. DT and EJ were supported by EU-REFRESH, EU-WISER, CLEAR (a Villum Kann Rasmussen Centre of Excellence Project on lake restoration) and CRES. We thank Prof. Andre De Roos for his insightful comments and Dr. Tom Andersen for his contribution to the text. JJ wishes to thank Drs. T. Aldenberg, Dr. L. Van Liere, Mr. M.J. 't Hart, Ir. M.H.J.L Jeuken, Ing. S. van Tol, Ir. J.S. Sloot and many others including the many people who provided lake data, for their contributions to PCLake. This is publication 4838 of the Netherlands Institute of Ecology (NIOO-KNAW). . - ISSN 1386-2588
РУБ Ecology + Limnology + Marine & Freshwater Biology

Аннотация: A large number and wide variety of lake ecosystem models have been developed and published during the past four decades. We identify two challenges for making further progress in this field. One such challenge is to avoid developing more models largely following the concept of others ('reinventing the wheel'). The other challenge is to avoid focusing on only one type of model, while ignoring new and diverse approaches that have become available ('having tunnel vision'). In this paper, we aim at improving the awareness of existing models and knowledge of concurrent approaches in lake ecosystem modelling, without covering all possible model tools and avenues. First, we present a broad variety of modelling approaches. To illustrate these approaches, we give brief descriptions of rather arbitrarily selected sets of specific models. We deal with static models (steady state and regression models), complex dynamic models (CAEDYM, CE-QUAL-W2, Delft 3D-ECO, LakeMab, LakeWeb, MyLake, PCLake, PROTECH, SALMO), structurally dynamic models and minimal dynamic models. We also discuss a group of approaches that could all be classified as individual based: super-individual models (Piscator, Charisma), physiologically structured models, stage-structured models and traitbased models. We briefly mention genetic algorithms, neural networks, Kalman filters and fuzzy logic. Thereafter, we zoom in, as an in-depth example, on the multi-decadal development and application of the lake ecosystem model PCLake and related models (PCLake Metamodel, Lake Shira Model, IPH-TRIM3D-PCLake). In the discussion, we argue that while the historical development of each approach and model is understandable given its 'leading principle', there are many opportunities for combining approaches. We take the point of view that a single 'right' approach does not exist and should not be strived for. Instead, multiple modelling approaches, applied concurrently to a given problem, can help develop an integrative view on the functioning of lake ecosystems. We end with a set of specific recommendations that may be of help in the further development of lake ecosystem models.


Доп.точки доступа:
Mooij, W.M.; Trolle, D.; Jeppesen, E.; Arhonditsis, G.; Belolipetsky, P.V.; Белолипецкий, Павел Викторович; Chitamwebwa, D.B.R.; Degermendzhy, A.G.; DeAngelis, D.L.; Domis, L.N.D.; Downing, A.S.; Elliott, J.A.; Fragoso, C.R.; Gaedke, U.; Genova, S.N.; Генова, Светлана Николаевна; Gulati, R.D.; Hakanson, L.; Hamilton, D.P.; Hipsey, M.R.; 't Hoen, J.; Hulsmann, S.; Los, F.H.; Makler-Pick, V.; Petzoldt, T.; Prokopkin, I.G.; Rinke, K.; Schep, S.A.; Tominaga, K.; Van Dam, A.A.; Van Nes, E.H.; Wells, S.A.; Janse, J.H.

    Mathematical modeling of the electrolytic obtaining of aluminum to solve technology-control problems
[Text] / V. M. Belolipetskii, T. V. Piskazhova // Russ. J. Non-Ferrous Metals. - 2013. - Vol. 54, Is. 5. - P398-402, DOI 10.3103/S1067821213050039. - Cited References: 5 . - ISSN 1067-8212
РУБ Metallurgy & Metallurgical Engineering

Аннотация: A thermal dynamic model of the electrolyzer is considered and certain production events are modeled. Results of variations in production parameters after controlling actions are considered.

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Доп.точки доступа:
Belolipetskii, V.M.; Белолипецкий, Виктор Михайлович; Piskazhova, T.V.

    Numerical solution of dynamic problems in block media with thin interlayers on supercomputers with GPUs
/ M. Varygina // Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics). - 2013. - Vol. 8236 LNCS: 5th International Conference on Numerical Analysis and Applications, NAA 2012 (15 June 2013 through 20 June 2013, Lozenetz. - P517-523, DOI 10.1007/978-3-642-41515-9_59 . -

Аннотация: Parallel computational algorithms for the modeling of dynamic interaction of elastic blocks through thin viscoelastic interlayers in structurally inhomogeneous media such as rock are worked out. Numerical algorithms are based on monotonous grid- characteristic schemes with the balanced number of time steps in layers and interlayers. The numerical results to demonstrate qualitative characteristics of wave propagation in materials with microstructure are shown. В© 2013 Springer-Verlag.

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Доп.точки доступа:
Варыгина, Мария Петровна

    Parallel program systems for problems of the dynamics of elastic-plastic and granular media
/ O. V. Sadovskaya // Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics). - 2013. - Vol. 8236 LNCS: 5th International Conference on Numerical Analysis and Applications, NAA 2012 (15 June 2013 through 20 June 2013, Lozenetz. - P471-478, DOI 10.1007/978-3-642-41515-9_53 . -

Кл.слова (ненормированные):
Cosserat continuum -- Dynamics -- elasticity -- granular medium -- parallel computational algorithm -- plasticity -- shock-capturing method

Аннотация: Parallel program systems for numerical solution of 2D and 3D problems of the dynamics of deformable media with constitutive relationships of rather general form on the basis of universal mathematical model describing small strains of elastic, elastic-plastic and granular materials are worked out. Computational algorithm is based on the splitting methods with respect to physical processes and spatial variables. Some computations of dynamic problems with and without taking into account the moment properties of a material were performed on clusters. В© 2013 Springer-Verlag.

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Держатели документа:
Institute of Computational Modeling SB RAS, Akademgorodok 50/44, 660036 Krasnoyarsk, Russian Federation

Доп.точки доступа:
Sadovskaya, O.V.; Садовская, Оксана Викторовна

    On thermodynamically consistent formulations of dynamic models of deformable media and their numerical implementation
/ V. M. Sadovskii // Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics). - 2013. - Vol. 8236 LNCS: 5th International Conference on Numerical Analysis and Applications, NAA 2012 (15 June 2013 through 20 June 2013, Lozenetz. - P479-486, DOI 10.1007/978-3-642-41515-9_54 . -

Кл.слова (ненормированные):
computational algorithm -- discontinuous solution -- Dynamics -- elasticity -- granular medium -- plastic shock wave -- variational inequality

Аннотация: Mathematical models of the dynamics of elastic-plastic and granular media are formulated as variational inequalities for hyperbolic operators with one-sided constraints describing the transition of a material in plastic state. On this basis a priori integral estimates are constructed in characteristic cones of operators, from which follows the uniqueness and continuous dependence on initial data of solutions of the Cauchy problem and of the boundary-value problems with dissipative boundary conditions. With the help of an integral generalization of variational inequalities the relationships of strong discontinuity in dynamic models of elastic-plastic and granular media are obtained, whose analysis allows us to calculate velocities of shock waves and to construct discontinuous solutions. Original algorithms of solution correction are developed which can be considered as a realization of the splitting method with respect to physical processes. В© 2013 Springer-Verlag.

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Доп.точки доступа:
Sadovskii, V.M.; Садовский, Владимир Михайлович

    High-Performance Computations in Numerical Modeling of Wave Propagation in Block Media with Thin Interlayers
/ M. Varygina // Proceedings of XLI International Summer School–Conference APM 2013. - 2013. - P107-113

Аннотация: Parallel computational algorithms for the numerical modeling of dynamic interactions of elastic blocks through thin elastic and viscoelastic interlayers in structurally inhomogeneous medium such as rock are developed. Monotonous grid-characteristic ENO-scheme with the balanced number of time steps in blocks and interlayers is used for the numerical solution. The algorithms are implemented in 1d and 2d cases with the CUDA technology (Compute Unified Device Architecture) for supercomputers with graphics processing units. The results of numerical analysis demonstrate peculiar quality of planar wave propagation in materials with layered microstructure.

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

Доп.точки доступа:
Варыгина, Мария Петровна

    Numerical simulation of deformation of a metal foam
/ 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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Держатели документа:
ИВМ СО РАН : 660036, Красноярск, Академгородок, 50, стр.44

Доп.точки доступа:
Садовская, Оксана Викторовна

    On the acoustic approximation of thermomechanical description of a liquid crystal
/ V. M. Sadovskii, O. V. Sadovskaya // Physical Mesomechanics. - 2013. - Vol. 16, № 4. - P312-318, DOI 10.1134/S102995991304005X . - ISSN 1029-9599

Кл.слова (ненормированные):
Klein-Gordon equation -- micropolar medium -- rotational waves -- thermoelasticity

Аннотация: Based on dynamic equations of a heterogeneous elastic medium which take into account rotational degrees of freedom of microstructure particles, a simplified mathematical model was constructed to describe the wave motions of a nematic liquid crystal under weak mechanical and temperature perturbations. It is shown that in the medium under plane deformation, the tangential stress obeys the Klein-Gordon equation of oscillatory particle rotation. Consideration is given to the possibility of initiating rotational waves in a nematic liquid crystal, which change its optical properties, due to heat sources acting at its boundary. © 2013 Pleiades Publishing, Ltd.

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

Доп.точки доступа:
Sadovskaya, O.V.; Садовская, Оксана Викторовна; Sadovsky V.M.

    The Simplest Model of Targeted Migration
[Текст] : статья / M. G. Sadovsky // Journal of Siberian Federal University. Mathematics & Physics = Журнал Сибирского федерального университета. Математика и физика. - 2012. - Т. 5, № 1. - С. 3-17

Кл.слова (ненормированные):
optimality -- selection -- projection -- maximization -- stability -- information

Аннотация: A simple model of targeted migration is studied. The model implies the global information access of the beings migrating from station to station. This approximation yields a special class of models which generater a semi-group. Various dynamic regimes, as well as the stability conditions are studied. Some further expansions of the modelling based on evolution optimality principle are considered.

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

Доп.точки доступа:
Садовский, Михаил Георгиевич

    A slow mode transition region adjoining the front boundary of a magnetic cloud as a relic of a convected solar wind feature: Observations and MHD simulation
[Text] / C. J. Farrugia [et al.] // J. Geophys. Res-Space Phys. - 2008. - Vol. 113. - Ст. A00B01, DOI 10.1029/2007JA012953. - Cited References: 38 . - ISSN 0148-0227
РУБ Astronomy & Astrophysics

Аннотация: We identify a planar, pressure-balanced structure bounded by sharp changes in the dynamic pressure plastered against the front boundary of the magnetic cloud which passed Earth on 20 November 2003. The front boundary of the magnetic cloud (MC) is particularly well-defined in this case, being located where the He(++)/H(+) number density ratio jumps from 4 to 10% for the first time and the proton plasma beta decreases sharply from similar to 1 to similar to 0.001. The feature, estimated to have a length scale similar to 50 RE in the Sun-Earth direction, bears close resemblance to a slow mode transition region in that the magnetic pressure decreases, the plasma pressure increases, and their temporal variations are anticorrelated. Using a 2-D MHD simulation, we hypothesize that a pressure-balanced structure was encountered by the MC en route to Earth. Our calculations reproduce qualitatively the major features of the observations. Using a simplified geometry suggested by the observations, we find that the lateral deflection speed of the plasma is less than the lateral expansion speed of the MC. We infer that the structure traversed the MC sheath in similar to 20 h, consistent with its crossing of the MC's shock at 0.6-0.7 AU. The finding is consistent with the recent paradigm according to which solar wind plasma and magnetic field tend to pile up in front of interplanetary ejecta because the expansion of the ejecta hinders the shocked solar wind plasma from deflecting effectively around the object. Also, the inferred "age'' of the layer contiguous to the surface of the MC, the earliest relic of its passage through the inner heliosphere, is in agreement with general estimates.


Доп.точки доступа:
Farrugia, C.J.; Erkaev, N.V.; Еркаев, Николай Васильевич; Taubenschuss, U.; Shaidurov, V.A.; Smith, C.W.; Biernat, H.K.

    Interchange instability of a curved current layer convecting in the magnetosheath from the bow shock towards the magnetopause
[Text] / I. L. Arshukova, N. V. Erkaev, H. K. Biernat // Ann. Geophys. - 2004. - Vol. 22, Is. 3. - P993-999. - Cited References: 16 . - ISSN 0992-7689
РУБ Astronomy & Astrophysics + Geosciences, Multidisciplinary + Meteorology & Atmospheric Sciences
Рубрики:
FLOW
Кл.слова (ненормированные):
magnetospheric physics -- magnetosheath

Аннотация: This paper deals with nonsteady perturbations of the magnetosheath parameters which are related to variations of the interplanetary magnetic field from north to south under a constant solar wind dynamic pressure. The magnetic field changes its direction within a thin layer which is convected with the plasma from the bow shock to the ionopause. In the course of time, this current layer is amplified during its motion towards the magnetopause. The intensity of the current is increasing, the layer thickness is decreasing, and the gradients of parameters are becoming much sharper while the layer is approaching the magnetopause. The curvature radius of this layer is decreasing while it is draping around the magnetopause. This curved layer structure with reversed magnetic field in the magnetosheath is found to be unstable with respect to the interchange instability. The growth rate of the instability is obtained for different positions of the layer.


Доп.точки доступа:
Arshukova, I.L.; Erkaev, N.V.; Еркаев, Николай Васильевич; Biernat, H.K.