Труды сотрудников ИВМ СО РАН

[Text] : статья / A.N. Gorban [et al.] // Physica A. - 1996. - 231. - p. 648-672
   Перевод заглавия: Траектории релаксации: глобальная аппроксимация
Аннотация: The paper intends to fill the gap of analytic approximate methods for non-linear space-independent dissipative systems equipped with the entropy functional. The key point of the analysis is an upper limiting state in the beginning of the relaxation. Extremal properties of this state are described and explicit estimations are derived. This limiting state is used to construct explicit approximations of the phase trajectories. Special attention is paid to accomplish positiv-ity, smoothness and the entropy growth along the approximate trajectories. The method is tested for the space-independent Boltzmann equation with various collisional mechanisms.

http://icm.krasn.ru/refextra.php?id=2092,
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ИВМ СО РАН : 660036, Красноярск, Академгородок, 50, стр.44

Доп.точки доступа:
Gorban, A.N.; Горбань, Александр Николаевич; Karlin, I.V.; Карлин, Илья Вениаминович; Nonnenmacher, T.F.; Zmievskii, V.B.; Змиевский В.Б.

[Text] : монография / V.K. Andreev, Y.A. Gaponenko, O.N. Goncharova, V.V. Pukhnachev. - Berlin [etc.] : Walter de Gruyter, 2012. - XV, 417 p. - (De Gruyter Studies in Mathematical Physics ; 5). - Библиогр.: с. 401-414. - Указ.: с. 415-420. - ISBN 978-3110258141 : Б. ц. - DOI 10.1515/9783110258592
Аннотация: Phenomena of convection are abundant in nature as well as in industry. This volume addresses the subject of convection from the point of view of both, theory and application. While the first three chapters provide a refresher on fluid dynamics and heat transfer theory, the rest of the book describes the modern developments in theory. Thus it brings the reader to the "front" of the modern research. This monograph provides the theoretical foundation on a topic relevant to metallurgy, ecology, meteorology, geo-and astrophysics, aerospace industry, chemistry, crystal physics, and many other fields

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Доп.точки доступа:
Gaponenko, Y.A.; Гапоненко, Юрий Анатольевич; Goncharova, O.N.; Гончарова, Ольга Николаевна; Pukhnachev, V.V.; Пухначев, Владислав Васильевич; Андреев, Виктор Константинович
Свободных экз. нет

/ A.V. Vyatkin // Autom. Remote Control. - 2013. - Vol. 74, Is. 2. - P325-330, DOI 10.1134/S0005117913020173. - Cited References: 9. - This work was supported by the Russian Foundation for Basic Research, project no. 08-01-00621, and by the Russian President's Program, project no. NSh-3431.2008.9. . - 6. - ISSN 0005-1179РУБ Automation & Control Systems + Instruments & Instrumentation

Аннотация: The behavior of the explicit Runge-Kutta methods having the second, fourth and eighth orders of accuracy is analyzed at the singular point in the two-body problem. Numerical solutions are compared with their analytical counterpart. As the adequacy criterion for an approximate solution, the conservation law of the total mechanical energy is considered.


Доп.точки доступа:
Vyatkin, A.V.; Вяткин, Александр Владимирович

[Text] : статья / V.V. Denisenko [et al.] // J. Atmos. Sol.-Terr. Phys. - 2013. - Vol. 102. - P341-353, DOI 10.1016/j.jastp.2013.05.019. - Cited References: 29. - This work is supported by Grants 09-06-91000, 12-05-00152 from the Russian Foundation for Basic Research. Additional support is due to the Austrian "Fonds zur Forderung der wissenschaftlichen Forschung" under Project I193-N16 and the "Verwaltungsstelle fur Auslandsbeziehungen" of the Austrian Academy of Sciences. The authors are grateful to the unknown reviewers for the fruitful detailed discussion. . - 13. - ISSN 1364-6826РУБ Geochemistry & Geophysics + Meteorology & Atmospheric Sciences

Аннотация: A quasi stationary three dimensional model of electric fields and currents in the conductor that includes the Earth's atmosphere and ionosphere is created. The results of the three dimensional model are simpler regarding interpretation and explanation than two dimensional ones. Known approaches regarding the ionosphere as a boundary condition at the upper boundary of the atmospheric conductor are analyzed. For the investigation of the electric field penetration from ground into the ionosphere it is sufficient to take into account only integral conductivity of the ionosphere. A mathematical simulation has shown that the resulting electric field in the ionosphere is negligible in contrast to the general point of view that such a penetration is a physical process which potentially creates ionospheric precursors of earthquakes. (C) 2013 Elsevier Ltd. All rights reserved.

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

Доп.точки доступа:
Denisenko, V.V.; Денисенко, Валерий Васильевич; Ampferer, M.; Pomozov, E.V.; Помозов, Егор Владимирович; Kitaev, A.V.; Китаев, Анатолий Валерьевич; Hausleitner, W.; Stangl, G.; Biernat, H.K.; Russian Foundation for Basic Research [09-06-91000, 12-05-00152]; Austrian "Fonds zur Forderung der wissenschaftlichen Forschung" [I193-N16]; "Verwaltungsstelle fur Auslandsbeziehungen" of the Austrian Academy of Sciences

[Text] / N.I. Kosarev, N.Y. Shaparev // Quantum Electron. - 2009. - Vol. 39, Is. 12. - pp. 1112-1116, DOI 10.1070/QE2009v039n12ABEH014094. - Cited References: 13 . - ISSN 1063-7818РУБ Engineering, Electrical & Electronic + Physics, Applied

Аннотация: We report a computer simulation study of light absorption, scattering and emission at 397 nm in an ultracold calcium ion plasma under resonant excitation. The results point to spectral asymmetry of light scattering, nonlinear absorption, and emission in the plasma. An approach is proposed for ultracold plasma diagnostics using resonant optical characteristics.


Доп.точки доступа:
Shaparev, N.Ya.; Шапарев, Николай Якимович; Косарев Н.И.

[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 1386-2588РУБ 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.

[Text] / T. Penza [et al.] // Planet Space Sci. - 2008. - Vol. 56, Is. 9. - P1260-1272, DOI 10.1016/j.pss.2008.04.005. - Cited References: 53 . - ISSN 0032-0633РУБ Astronomy & Astrophysics

Аннотация: We investigate the efficiency of the atmospheric mass loss due to hydrodynamic blow-off over the lifetime of the exoplanet HD209458b by studying numerically its hydrogen wind for host star X-ray and EUV (XUV) fluxes between 1 and 100 times that of the present Sun. We apply a time-dependent numerical algorithm which is able to solve the system of hydrodynamic equations straight through the transonic point of the flow including Roche lobe effects. The mass loss rates are calculated as functions of the absorbed energy in the thermosphere. Depending on the heating efficiency for a hydrogen-rich thermosphere the maximum temperature obtained in our study at 1.5R(p1) by neglecting IR cooling is about 5000-10,000 K for heating efficiencies of 10% and 60%, respectively. We find that the upper atmosphere of HD209458b experiences hydrodynamic blow-off even at such low temperatures if one does not neglect gravitational effects caused by the proximity of the planet to its Roche lobe boundary. Depending on the heating efficiency, we find from the solution of the hydrodynamic equations of mass, momentum, and energy balance that energy-limited mass loss rate estimations overestimate the realistic mass loss rate at present time for HD209458b by several times. Using the maximum heating efficiency for hydrogen-rich atmospheres of 60% we find that HD209458b may experience an atmospheric mass loss rate at present time of about 3.5 x 10(10) g s(-1). The mass loss rate evolves to higher values for higher XUV fluxes expected during the early period of the planet's host star evolution, reaching values of several times 10(12) gs(-1). The integrated mass loss is found to be between 1.8% and 4.4% of the present mass of HD209458b. We found that the influence of the stellar tidal forces on atmospheric loss (the Roche lobe effect) is not significant at 0.045 AU. For a similar exoplanet, but at closer orbital distances <= 0.02 AU, the combined effect of the Roche lobe and the high XUV radiation result in much higher thermal loss rates of about 2.6 x 10(11) g s(-1) and even more for early stages. This leads to a total loss over 4 Gyr of 27.5% of the planetary mass. (c) 2008 Elsevier Ltd. All rights reserved.

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Доп.точки доступа:
Penza, T.; Erkaev, N.V.; Еркаев, Николай Васильевич; Kulikov, Y.N.; Langmayr, D.; Lammer, H.; Micela, G.; Cecchi-Pestellini, C.; Biernat, H.K.; Selsis, F.; Barge, P.; Deleuil, M.; Leger, A.

[Text] / G. F. Jaritz [et al.] // Astron. Astrophys. - 2005. - Vol. 439, Is. 2. - P771-775, DOI 10.1051/0004-6361:20052946. - Cited References: 32 . - ISSN 0004-6361РУБ Astronomy & Astrophysics

Аннотация: Theoretical studies and recent observational evidence of the expansion of the atmospheres of short-periodic exoplanets show that the atmospheres extend up to several planetary radii. This indicates that the atmospheres experience blow-off conditions. Because of the short orbital distance to their host stars, the expansion of the upper atmosphere is no longer radially symmetric, but depends on the direction to the central body, resulting in a deformation of the expanded atmosphere. We show the connection between atmospheric expansion, tidal forces and effects of the Roche potential and find that HD209458 b, OGLE-TR-10 b and OGLE-TR-111 b are most likely in a state of classical hydrodynamical blow-off because the distance where blow-off can occur is less than the distance to the Lagrangian point L1. On the other hand, OGLE-TR-56 b, OGLE-TR-113 b, OGLE-TR-132 b and TreS-1 experience a geometrical blow-off defined by the Roche lobe as proposed by Lecavelier des Etangs et al. (2004, A&A, 418, L1). Our results have important implications for the evolution of short periodic gas giants, because the Roche lobe overflow of the atmosphere can lead to lower mass loss rates over the exoplanets history, compared to gas giants which experience hydrodynamic expansion and loss unaffected by this boundary. Thus, massive exoplanets like OGLE-TR-56 b in very close orbital distances are subject to geometrical blow-off conditions, this results in a total mass loss for this particular exoplanet of the order of about 3 x 10(-2) M-pl over the planets age, even if current mass loss rates of about 2 x 10(11) g s(-1) are calculated. If the exoplanet effected by the geometrical blow-off is more massive, the mass loss rate is even lower. However, giant exoplanets like HD209458 b, OGLE-TR-10 b and OGLE-TR-111 b at orbital distances of about 0.05 AU may experience classical hydrodynamic blow-off conditions, which can result in higher mass loss rates. Thus, such planets may shrink to their core sizes during the X-ray and EUV active periods of their host stars as proposed by Lammer et al. ( 2003, ApJ, L121, 598) and Bara. e et al. (2004, A& A, 419, L13).


Доп.точки доступа:
Jaritz, G.F.; Endler, S.; Langmayr, D.; Lammer, H.; Griessmeier, J.M.; Erkaev, N.V.; Еркаев, Николай Васильевич; Biernat, H.K.

[Text] / H. Lammer [et al.] // Celest. Mech. Dyn. Astron. - 2005. - Vol. 92, Is. 01.03.2013. - P273-285, DOI 10.1007/s10569-005-0004-4. - Cited References: 27 . - ISSN 0923-2958РУБ Astronomy & Astrophysics + Mathematics, Interdisciplinary Applications

Аннотация: The region around a star where a life-supporting biosphere can evolve is the so-called Habitable Zone (HZ). The current definition of the HZ is based only on the mass-luminosity relation of the star and climatological and meteorological considerations of Earth-like planets, but neglects atmospheric loss processes due to the interaction with the stellar radiation and particle environment. From the knowledge of the planets in the Solar System, we know that planets can only evolve into a habitable world if they have a stable orbit around its host star and if they keep the atmosphere and water inventory during: (i) the period of heavy bombardment by asteroids and comets and (ii) during the host stars' active X-ray and extreme ultraviolet (XUV) and stellar wind periods. Impacts play a minor role for planets with the size and mass like Earth, while high XUV fluxes and strong stellar winds during the active periods of the young host star can destroy the atmospheres and water inventories. We show that XUV produced temperatures in the upper atmospheres of Earth-like planets can lead to hydrodynamic "blow off", resulting in the total loss of the planets water inventory and atmosphere, even if their orbits lie inside the HZ. Further, our study indicates that Earth-like planets inside the HZ of low mass stars may not develop an atmosphere, because at orbital distances closer than 0.3 AU, their atmospheres are highly affected by strong stellar winds and coronal mass ejections (CME's). Our study suggests that planetary magnetospheres will not protect the atmosphere of such planets, because the strong stellar wind of the young star can compress the magnetopause to the atmospheric obstacle. Moreover, planets inside close-in HZ's are tidally locked, therefore, their magnetic moments are weaker than those of an Earth-like planet at 1 AU. Our results indicate that Earth-like planets in orbits of low mass stars may not develop stable biospheres. From this point of view, a HZ, where higher life forms like on Earth may evolve is possibly restricted to higher mass K stars and G stars.


Доп.точки доступа:
Lammer, H.; Kulikov, Y.N.; Penz, T.; Leitner, M.; Biernat, H.K.; Erkaev, N.V.; Еркаев, Николай Васильевич

[Text] / T. Penz [et al.] ; ed.: O. Witasse // PLANETARY ATMOSPHERES, IONOSPHERES, AND MAGNETOSPHERES. Ser. ADVANCES IN SPACE RESEARCH : ELSEVIER SCIENCE LTD, 2005. - Vol. 36: 35th COSPAR Scientific Assembly (JUL 18-25, 2004, Paris, FRANCE), Is. 11. - P2049-2056, DOI 10.1016/j.asr.2004.11.039. - Cited References: 20 . - ISBN 0273-1177РУБ Engineering, Aerospace + Astronomy & Astrophysics + Geosciences, Multidisciplinary + Meteorology & Atmospheric Sciences

Аннотация: It is known from Pioneer Venus measurements that at the Venusian ionopause wave-like structures develop, which can detach in the form of ionospheric plasma clouds. This phenomenon is assumed to occur due to the Kelvin-Helmholtz instability, which can appear in large regions of the Venusian ionopause. Recent studies of Mars Global Surveyor measurements indicate that wave-like structures and plasma clouds also detach from the Martian ionopause. Therefore, these features seem to be common for the solar wind interaction of non-magnetized planets. We study the conditions at the Martian ionopause with respect to the occurrence of several MHD instabilities. The conditions in the magnetosheath are modeled by a semi-analytical MHD simulation that includes mass loading. The ionospheric parameter needed for the model calculations are taken from a global hybrid model. The stability of the Martian ionopause against the Kelvin-Helmholtz, the Rayleigh-Taylor, and the interchange instability is analyzed. Further, we suggest that including the Hall term in the description of the Kelvin-Helmholtz instability gives a current in the planetary boundary layer resulting in a shear flow compared with the ionospheric plasma, which can lead to an unstable boundary layer near the subsolar point. Since the interchange instability depends on the curvature of the magnetic field lines, we additionally study the influence of the strong curvature of the Martian ionopause due to the localized, remnant, crustal magnetism appearing mainly in the southern hemisphere of Mars. (c) 2004 COSPAR. Published by Elsevier Ltd. All rights reserved.


Доп.точки доступа:
Penz, T.; Arshukova, I.L.; Terada, N.; Shinagawa, H.; Erkaev, N.V.; Еркаев, Николай Васильевич; Biernat, H.K.; Lammer, H.; Witasse, O. \ed.\

[Text] / T. Penz [et al.] // Planet Space Sci. - 2004. - Vol. 52, Is. 13. - P1157-1167, DOI 10.1016/j.pss.2004.06.001. - Cited References: 53 . - ISSN 0032-0633РУБ Astronomy & Astrophysics

Аннотация: Mars Global Surveyor detected cold electrons above the Martian ionopause, which can be interpreted as detached ionospheric plasma clouds. Similar observations by the Pioneer Venus Orbiter electron temperature probe showed also extreme spatial irregularities of electrons in the form of plasma clouds on Venus, which were explained by the occurrence of the Kelvin-Helmholtz instability. Therefore, we suggest that the Kelvin-Helmholtz instability may also detach ionospheric plasma clouds on Mars. We investigate the instability growth rate at the Martian ionopause resulting from the flow of the solar wind for the case where the interplanetary magnetic field is oriented normal to the flow direction. Since the velocity shear near the subsolar point is very small, this area is stable with respect to the Kelvin-Helmholtz instability. We found that the highest flow velocities are reached at the equatorial flanks near the terminator plane, while the maximum plasma density in the terminator plane appears at the polar areas. By comparing the instability growth rate with the magnetic barrier formation time, we found that the instability can evolve into a non-linear stage at the whole terminator plane but preferably at the equatorial flanks. Escape rates of O+ ions due to detached plasma clouds in the order of about 2 x 10(23)-3 x 10(24) s(-1) are found. Thus, atmospheric loss caused by the Kelvin-Helmholtz instability should be comparable with other non-thermal loss processes. Further, we discuss our results in view of the expected observations of heavy ion loss rates by ASPERA-3 on board of Mars Express. (C) 2004 Elsevier Ltd. All rights reserved.


Доп.точки доступа:
Penz, T.; Erkaev, N.V.; Еркаев, Николай Васильевич; Biernat, H.K.; Lammer, H.; Amerstorfer, U.V.; Gunell, H.; Kallio, E.; Barabash, S.; Orsini, S.; Milillo, A.; Baumjohann, W.

[Text] / I. L. Arshukova, N. V. Erkaev // Geomagn. Aeron. - 2000. - Vol. 40, Is. 6. - P692-698. - Cited References: 8 . - ISSN 0016-7932РУБ Geochemistry & Geophysics

Аннотация: The interchange instability of the magnetospheric boundary at the subsolar point has been considered in the present paper on the basis of the magnetic gas-dynamic model (MGD approximation). The magnetopause is simulated by a thin layer of constant thickness and finite curvature radius. Two cases of changing magnetic field and plasma density at crossing the magnetopause were examined: (1) plasma parameters and the magnetic field are constant inside the magnetopause and change by a jump at its boundaries, and (2) all parameters continuously vary from their values in the magnetosheath to those in the magnetosphere, In the first case, an analytical solution has been found, and the linearized problem of small disturbances of the magnetospheric boundaries has been numerically solved in the second case. The growth rate of intel change instability has been determined depending on the direction of the interplanetary magnetic field, wavenumber, curvature radius of the magnetospheric boundary, and magnetopause thickness.


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

[Text] / C. J. Farrugia, H. K. Biernat, N. V. Erkaev // Planet Space Sci. - 1998. - Vol. 46, Is. 5. - P507-514, DOI 10.1016/S0032-0633(97)00225-0. - Cited References: 20 . - ISSN 0032-0633РУБ Astronomy & Astrophysics

Аннотация: The solar wind flow past nonaxisymmetric magnetospheres exhibits features which are absent in the case of axisymmetric magnetospheres such as that of Earth. We discuss results obtained by a numerical integration of the dissipationless MHD equations, under simplifying assumptions, and apply them to the two outer planets Jupiter and Saturn, both of whose magnetospheres depart substantially from axisymmetry. We model these magnetospheres as paraboloids with two different radii of curvature at the subsolar point, L-0 and L-1, where L-0 and L-1 refer to a magnetopause cut containing the rotational axis, and to the rotational equator, respectively (L-0 L-1). The degree of flattening is expressed by a parameter q :


Доп.точки доступа:
Farrugia, C.J.; Biernat, H.K.; Erkaev, N.V.; Еркаев, Николай Васильевич

[Text] / C. J. Farrugia, H. K. Biernat, N. V. Erkaev // PLANETARY IONOSPHERES AND MAGNETOSPHERES. Ser. ADVANCES IN SPACE RESEARCH-SERIES : PERGAMON PRESS LTD, 1997. - Vol. 20: C3.2 Symposium of COSPAR Scientific Commission C on Planetary Ionospheres and Magnetospheres, at the 31st COSPAR Scientific Assembly (JUL 14-21, 1996, BIRMINGHAM, ENGLAND), Is. 2. - P209-213, DOI 10.1016/S0273-1177(97)00535-8. - Cited References: 15 . - ISBN 0273-1177. - ISBN 0-08-043297-2РУБ Engineering, Aerospace + Astronomy & Astrophysics + Geosciences, Multidisciplinary + Meteorology & Atmospheric Sciences

Аннотация: We discuss results on the solar wind flow past the non-axisymmetric magnetospheres of planets Jupiter and Saturn obtained by integrating numerically the dissipationless MHD equations under simplifying assumptions. We model these equatorially broadened magnetospheres as paraboloids with two different radii of curvature at the subsolar point. The thickness of the magnetosheath and the width and structure of the plasma depletion layer are found to be strong functions of the orientation of the interplanetary magnetic field (IMF). The effect of the IMF on the magnetosheath is strongest (weakest) when the IMF is directed perpendicular (parallel) to the rotational equator. For any intermediate IMF orientation, a smooth rotation of the magnetosheath magnetic field towards the direction of the planet's rotational axis is superimposed on the field strength enhancement (and the density reduction) as the respective magnetopauses are approached. These effects are more pronounced at Jupiter than at Saturn. (C) 1997 COSPAR. Published by Elsevier Science Ltd.


Доп.точки доступа:
Farrugia, C.J.; Biernat, H.K.; Erkaev, N.V.; Еркаев, Николай Васильевич

[Text] / H. K. BIERNAT [et al.] // Planet Space Sci. - 1995. - Vol. 43, Is. 9. - P1105-1120, DOI 10.1016/0032-0633(95)00054-9. - Cited References: 31 . - ISSN 0032-0633РУБ Astronomy & Astrophysics

Аннотация: We use the magnetohydrodynamic approach to calculate all plasma and magnetic field quantities along a line normal to the magnetopause, beginning at the bow shock, through the magnetosheath and magnetopause, and into the magnetosphere. Our method is based on a perturbation calculation, where we expand in orders of 1/M(A infinity), with M(A infinity) the Alfven Mach number upstream of the bow shock. The calculations are carried out (1) in the noon-midnight meridian at latitudes just south of the northern cusp, and (2) in the equatorial flank region. Our calculations are for an interplanetary magnetic field (IMF) which is directed perpendicular to the upstream solar wind. We consider two orientations of the IMF. In one case, the interplanetary field points due south, i.e. antiparallel to the magnetospheric field in the subsolar point. In the second case, it lies in the equatorial plane and points from dusk to dawn. For each of these different orientations of the IMF, in situ observations of reconnection have been made. In the magnetosheath region adjacent to the magnetopause, i.e. in the so-called magnetic barrier, the magnetic forces react back on the plasma flow. This effect is included consistently in the calculation by the use of a special coordinate system. The magnetic field tension accelerates the plasma in a direction perpendicular to the field and thus the magnetic field produces an asymmetry in the flow field. At the magnetopause we describe shock-type reconnection, taking as input on the magnetosheath side the results of the above calculation and taking at the magnetospheric side typical values for the outer boundary of the magnetosphere. The format in which the results are presented is similar to that used in the presentation of bulk parameters and magnetic field measurements obtained from spacecraft.


Доп.точки доступа:
BIERNAT, H.K.; BACHMAIER, G.A.; KIENDL, M.T.; Erkaev, N.V.; Еркаев, Николай Васильевич; MEZENTSEV, A.V.; FARRUGIA, C.J.; SEMENOV, V.S.; RIJNBEEK, R.P.

[Text] / C. J. Farrugia [et al.] // Adv. Space Res. - 2009. - Vol. 44, Is. 11. - P1288-1294, DOI 10.1016/j.asr.2009.07.003. - Cited References: 29. - Work supported by Project P20145-N16 and by I.2/04 Osterreichische Austauschdient. . - ISSN 0273-1177РУБ Astronomy & Astrophysics + Geosciences, Multidisciplinary + Meteorology & Atmospheric Sciences

Аннотация: Using a serendipitous configuration of the ACE and Wind spacecraft, we monitor the response of the distant geomagnetic tail (similar to-220 R(E)) to an abrupt, approx. fivefold pressure drop (from similar to 19.0 to similar to 3.5 nPa) at the front boundary of a magnetic cloud (MC) on November 20, 2003. The interplanetary data are from ACE in orbit around the L1 point. The far-tail observations are from Wind, which was nominally in the magnetosheath, separated from the Sun-Earth line by similar to 40 R(E). The magnetic field in the innermost sheath region of the MC had a large B(y) (similar to 30 nT) and substantial and variable flows lateral to the Sun-Earth line. There was also a significant northward field (similar to 35 nT), unique in the vicinity of this MC. These extreme values are reached in a filament forming the earliest relic of material accreted by the MC en route to Earth. The effects resulting from these on the far geomagnetic tail are: (1) expansion, (2) tail twisting, and (3) tail tilting. These extreme conditions were in part responsible for a crossing by Wind of a neutral sheet which is tilted by similar to 85 degrees to the ecliptic. Further, Wind made two successive excursions deep into the geomagnetic tail, in the first of which a tailward flow burst of similar to 1200 km/s was observed. The dayside part of the interaction of the sudden and large dynamic pressure drop with the bow shock is studied with a local 3D MHD simulation. This work is a contribution to the area ICME/MC-sheaths-magnetosheath interactions. (C) 2009 COSPAR. Published by Elsevier Ltd. All rights reserved.


Доп.точки доступа:
Farrugia, C.J.; Erkaev, N.V.; Еркаев, Николай Васильевич; Maynard, N.C.; Richardson, I.G.; Sandholt, P.E.; Langmayr, D.; Ogilvie, K.W.; Szabo, A.; Taubenschuss, U.; Torbert, R.B.; Biernat, H.K.; NASA [NNG05GG25G, NNX08AD11G]; RFBR [07-05-00135]; RAS [2.16, 16.3]; Osterreichische Austauschdient [I.2/04]; [P20145-N16]

[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] : статья / A. Mialdun [et al.] // Physical review letters. - 2008. - Vol. 101. - Ст. 084501DOI 10.1103/PhysRevLett.101.084501 . -
Аннотация: We report experimental evidence of convection caused by translational vibration of nonuniformly heated fluid in low gravity. The theory of vibrational convection in weightlessness is well developed but direct experimental proof has been missing. An innovative point of the experiment is the observation of a temperature field in the front and side views of the cubic cell. In addition, particle tracing is employed. The evolution of this field is studied systematically in a wide range of frequencies and amplitudes. The flow structures reported in previous numerical studies are confirmed. The transition from four-vortex flow to the pattern with three vortices is observed in the transient state.

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

Доп.точки доступа:
Mialdun, A.; Ryzhkov, I.I.; Рыжков, Илья Игоревич; Melnikov, D.E.; Shevtsova, V.

[Text] / O. V. Kaptsov // Program. Comput. Softw. - 2014. - Vol. 40, Is. 2. - P63-70, DOI 10.1134/S0361768814020054. - Cited References: 23. - This study was supported by the Russian Foundation for Basic Research (project nos. 12-01-00648-a and 10-01-00435-a) and by the Grant for Support of Leading Scientific Schools (NSh 544.2012.1). . - ISSN 0361-7688. - ISSN 1608-3261РУБ Computer Science, Software Engineering

Аннотация: Differential algebra of convergent power series that depend on an arbitrary finite number of variables is considered. The concept of a passive family of generators is defined for a differential ideal of this algebra. It is a further extension of the concept of the Groebner basis. The theorem that allows checking whether a family of generators is passive and ensures that the point solution of an infinite system of equations exists and is unique in this algebra is proved.

Полный текст

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

Доп.точки доступа:
Kaptsov, O.V.; Капцов, Олег Викторович; Russian Foundation for Basic Research [12-01-00648-a, 10-01-00435-a]; Grant for Support of Leading Scientific Schools [NSh 544.2012.1]

/ N. D. Podufalov // Ukrainian Mathematical Journal. - 1992. - Vol. 43, Is. 7-8. - P1034-1035, DOI 10.1007/BF01058716 . - ISSN 0041-5995
Аннотация: We study questions of the hereditariness of the property of (?, ?)-transitivity (the property of being a plane of translations) of a finite protective plane for its subplanes. In particular it is shown that hereditariness holds for subplanes containing the point ?. В© 1992 Plenum Publishing Corporation.

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Держатели документа:
Computation Center, Siberian Branch, Academy of Sciences of the USSR, Krasnoyarsk, Russian Federation
ИВМ СО РАН

Доп.точки доступа:
Podufalov, N.D.