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    Simultaneously dissipative operators and the infinitesimal moore effect in interval spaces
[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
   В3
   V30

    MHD-Control of Gas Flow in the Tract Hypersonic Ramjet Engine
[Text] : статья / E. N. Vasilyev, V. A. Derevyanko, A. N. Mierau // The 3rd Workshop on Magneto-Plasma Aerodynamics in Aerospase Applications. - Moscow, 2001. - p. 160-164
ГРНТИ

Аннотация: Nowadays in leading countries of the world active research has been conducted on developing the perspective hypersonic aerospace aircraft. One of the key directions of research on this problem is the development highly efficient hypersonic ramjet engine (HRE). It is known that the efficiency of HRE with supersonic flow velocities in the combustion chamber decreases with the increasing of flight velocities. The basic losses take place in the combustion chamber as firstly the relative losses of working capacity of gas is considerably increasing at the heat supply, secondly because of high speed of the flow the quality of fuel confusion with the air on the bounded length considerably deteriorates and the completeness of combustion declines. The remarks of estimates demonstrate that for this reason the application of HRE is bounded evidently with the Mach numbers of flight that doesn't exceed 11-12. At the same time the thermodynamic estimates demonstrate the considerable reserve on the specific characteristics. This reserve can partly be realized by the reconstruction of the structure of the current using MHD-interaction.

http://icm.krasn.ru/refextra.php?id=2342,
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ИВМ СО РАН : 660036, Красноярск, Академгородок, 50, стр.44

Доп.точки доступа:
Derevyanko, V.A.; Деревянко, Валерий Александрович; Mierau, A.N.; Васильев, Евгений Николаевич
   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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Держатели документа:
ИВМ СО РАН : 660036, Красноярск, Академгородок, 50, стр.44

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

    Numerical modeling of operation of high-pressure detonation MHD-generator
[Text] : статья / V.V. Derevyanko // Thermophysics and Aeromechanics. - 2001. - Vol. 8, № 3

Аннотация: The numerical modeling of the operation of a detonation MHD generator with T-layer has been performed at large pressures in the duct. It is shown that the radiation absorption inside the T-layer leads to a considerable variation of the layer characteristics, increase in the specific power and generator efficiency.

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

Доп.точки доступа:
Деревянко, Виктор Валерьевич

    (2,1)-method for solving stiff nonautonomous problems
[Text] : статья / E. A. Novikov // Automation and Remote Control. - 2012. - Vol. 73, Iss. 1. - p. 191-197DOI 10.1134/S0005117912010183 . -

Аннотация: An L-stable (2,1)-method with second-order accuracy is developed for solving stiff nonautonomous problems. At each step, the right-hand side of the system, as well as Jacobian matrix decomposition are evaluated only once. Efficiency of the integration method is illustrated using ring modulator calculation as an example.

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Доп.точки доступа:
Новиков, Евгений Александрович

    Solution of Assimilation Observation Data Problem for Shallow Water Equations for SMP-Nodes Cluster
[Текст] : статья / E. D. Karepova, E. Dementyeva // Parallel Computing Technologies. - 2011. - Vol. 6873. - p. 444-451. - (Lecture Notes in Computer Science)DOI 10.1007/978-3-642-23178-0_39 . -

Кл.слова (ненормированные):
data assimilation problem -- finite elements method and high performance computation

Аннотация: The ill-posed inverse problem of propagation of long waves in a domain of arbitrary form with the sufficiently smooth boundary on a sphere is consider. Numerical solution is based on finite elements method. Parallel software using MPI is performed. We compared efficiency of two popular implementations of the MPI standard and studied the behavior of our software when using various ways of memory allocation.

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Доп.точки доступа:
Dementyeva, E.V.; Дементьева, Екатерина Васильевна; Карепова, Евгения Дмитриевна

    Probing the blow-off criteria of hydrogen-rich 'super-Earths'
/ H. Lammer [et al.] // Mon. Not. Roy. Astron. Soc. - 2013. - Vol. 430, Is. 2. - P1247-1256, DOI 10.1093/mnras/sts705. - Cited References: 85. - NVE, KGK, MLK and HL acknowledge the support by the FWF NFN project S116 'Pathways to Habitability: From Disks to Active Stars, Planets and Life', and the related FWF NFN subprojects, S116 606-N16 'Magnetospheric Electrodynamics of Exoplanets' and S116607-N16 'Particle/Radiative Interactions with Upper Atmospheres of Planetary Bodies Under Extreme Stellar Conditions'. KGK, HL and PO thank also the Helmholtz Alliance project 'Planetary Evolution and Life'. ML and PO acknowledge support from the FWF project P22950-N16. NVE acknowledges support by the RFBR grant No 12-05-00152-a. The authors also acknowledge support from the EU FP7 project IMPEx (No. 262863) and the EUROPLANET-RI projects, JRA3/EMDAF and the Na2 science working group WG5. The authors thank the International Space Science Institute (ISSI) in Bern, and the ISSI team 'Characterizing stellar- and exoplanetary environments'. Finally, we thank an anonymous referee for interesting suggestions and recommendations which helped to improve the article. . - 10. - ISSN 0035-8711
РУБ Astronomy & Astrophysics

Аннотация: The discovery of transiting 'super-Earths' with inflated radii and known masses, such as Kepler-11b-f, GJ 1214b and 55 Cnc e, indicates that these exoplanets did not lose their nebula-captured hydrogen-rich, degassed or impact-delivered protoatmospheres by atmospheric escape processes. Because hydrodynamic blow-off of atmospheric hydrogen atoms is the most efficient atmospheric escape process we apply a time-dependent numerical algorithm which is able to solve the system of 1D fluid equations for mass, momentum and energy conservation to investigate the criteria under which 'super-Earths' with hydrogen-dominated upper atmospheres can experience hydrodynamic expansion by heating of the stellar soft X-rays and extreme ultraviolet (XUV) radiation and thermal escape via blow-off. Depending on orbit location, XUV flux, heating efficiency and the planet's mean density our results indicate that the upper atmospheres of all 'super-Earths' can expand to large distances, so that except for Kepler-11c all of them experience atmospheric mass-loss due to Roche lobe overflow. The atmospheric mass loss of the studied 'super-Earths' is one to two orders of magnitude lower compared to that of 'hot Jupiters' such as HD 209458b, so that one can expect that these exoplanets cannot lose their hydrogen envelopes during their remaining lifetimes.


Доп.точки доступа:
Lammer, H.; Erkaev, N.V.; Еркаев, Николай Васильевич; Odert, P.; Kislyakova, K.G.; Leitzinger, M.; Khodachenko, M.L.

    Emergency situations monitoring using OLAP tehnology
[Text] / T.G. Penkova, A.V. Korobko, V.V. Nicheporchuk // MIPRO 2012 - 35th International Convention on Information and Communication Technology, Electronics and Microelectronics - Proceedings. - 2012. - 35th International Convention on Information and Communication Technology, Electronics and Microelectronics, MIPRO 2012 (21 May 2012 through 25 May 2012, Opatija) Conference code: 91931. - Ст. 6240906. - pp. 1595-1600 . -
Аннотация: An approach to efficiency improvement of monitoring of the emergency situations for the Siberian region is suggested in this paper. It is based on integration of data processing and storage technologies: Data Warehouse, OLAP and Expert systems. The data warehouse provides accumulation of data from isolated monitoring services. The OLAP tools allow a user to perform multiaspect monitoring of natural and anthropogenic emergency situations. The expert systems technology enables user to estimate of the emergencies risk based on state indicators. Suggested original methods and tools are embedded in emergency situations monitoring system "Espla-M". The system "Espla-M" is implemented in Ministry of emergency of Siberian Region. В© 2012 MIPRO.

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Доп.точки доступа:
Penkova, T.G.; Пенькова, Татьяна Геннадьевна; Korobko, A.V.; Коробко, Анна Владимировна; Nicheporchuk, V.V.; Ничепорчук, Валерий Васильевич

    The role of magnetic handedness in magnetic cloud propagation
[Text] / U. Taubenschuss [et al.] // Ann. Geophys. - 2010. - Vol. 28, Is. 5. - pp. 1075-1100, DOI 10.5194/angeo-28-1075-2010. - Cited References: 92. - The author appreciates financial support on behalf of the projects 06/9690 from the Austrian Research Community and A3-12T63/2007-1 from the Styrian government. Participation at the ISSS8 was made possible due to the travel fellowship of UCLA. Nikolai Erkaev acknowledges support by RFBR grants Nos. 07-05-00135 and 09-05-91000-ANF. Charles Farrugia received NASA grants NNG06GD41G and NNX08AD11G. Christian Mostl and Ute Amerstorfer work under FWF projects P20145N16 and P21051-N16 of the Austrian Science Foundation, respectively. . - ISSN 0992-7689
РУБ Astronomy & Astrophysics + Geosciences, Multidisciplinary + Meteorology & Atmospheric Sciences

Аннотация: We investigate the propagation of magnetic clouds (MCs) through the inner heliosphere using 2.5-D ideal magnetohydrodynamic (MHD) simulations. A numerical solution is obtained on a spherical grid, either in a meridional plane or in an equatorial plane, by using a Roe-type approximate Riemann solver in the frame of a finite volume approach. The structured background solar wind is simulated for a solar activity minimum phase. In the frame of MC propagation, special emphasis is placed on the role of the initial magnetic handedness of the MC's force-free magnetic field because this parameter strongly influences the efficiency of magnetic reconnection between the MC's magnetic field and the interplanetary magnetic field. Magnetic clouds with an axis oriented perpendicular to the equatorial plane develop into an elliptic shape, and the ellipse drifts into azimuthal direction. A new feature seen in our simulations is an additional tilt of the ellipse with respect to the direction of propagation as a direct consequence of magnetic reconnection. During propagation in a meridional plane, the initial circular cross section develops a concave-outward shape. Depending on the initial handedness, the cloud's magnetic field may reconnect along its backside flanks to the ambient interplanetary magnetic field (IMF), thereby losing magnetic flux to the IMF. Such a process in combination with a structured ambient solar wind has never been analyzed in detail before. Furthermore, we address the topics of force-free magnetic field conservation and the development of equatorward flows ahead of a concave-outward shaped MC. Detailed profiles are presented for the radial evolution of magnetoplasma and geometrical parameters. The principal features seen in our MHD simulations are in good agreement with in-situ measurements performed by spacecraft. The 2.5-D studies presented here may serve as a basis under more simple geometrical conditions to understand more complicated effects seen in 3-D simulations.


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

    Mass loss from "Hot Jupiters" - Implications for CoRoT discoveries, Part II: Long time thermal atmospheric evaporation modeling
[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 0032-0633
РУБ 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.

    Loss of hydrogen and oxygen from the upper atmosphere of Venus
[Text] / H. Lammer [et al.] // Planet Space Sci. - 2006. - Vol. 54, Is. 13-14. - P1445-1456, DOI 10.1016/j.pss.2006.04.022. - Cited References: 93 . - ISSN 0032-0633
РУБ Astronomy & Astrophysics

Аннотация: Atmospheric escape from the upper atmosphere of Venus is mainly influenced by the loss of hydrogen and oxygen caused by the interaction of solar radiation and particle flux with the unprotected planetary environment. Because one main aim of the ASPERA-4 particle/plasma and VEX-MAG magnetic field experiments on board of ESA's forthcoming Venus Express mission is the investigation of atmospheric erosion processes from the planet's ionosphere-exosphere environment, we study the total loss of hydrogen and oxygen and identified the efficiency of several escape mechanisms involved. For the estimation of pick up loss rates we use a gas dynamic test particle model and obtained average loss rates for H+, and O+ pick up ions of about 1 x 10(25) s(-1) and about 1.6 x 10(25) s(-1), respectively. Further, we estimate ion loss rates due to detached plasma clouds, which were observed by the pioneer Venus orbiter and may be triggered by the Kelvin-Helmholtz instability of about 0.5-1 x 10(25) s(-1). Thermal atmospheric escape processes and atmospheric loss by photo-chemically produced oxygen atoms yield negligible loss rates. Sputtering by incident pick up O+ ions give O atom loss rates in the order of about 6 x 10(24) s(-1). On the other hand, photo-chemically produced hot hydrogen atoms are a very efficient loss mechanism for hydrogen on Venus with a global average total loss rate of about 3.8 x 10(25) s(-1), which is in agreement with Donahue and Hartle [1992. Solar cycle variations in H+ and D+ densities in the Venus ionosphere: implications for escape. Geophys. Res. Lett. 12, 2449-2452] and of the same order but less than the estimated H+ ion outflow on the Venus nightside of about 7.0 x 10(25) s(-1) due to acceleration by an outward electric polarization force related to ionospheric holes by Hartle and Grebowsky [1993. Light ion flow in the nightside ionosphere of Venus. J. Geophys. Res. 98, 7437-7445]. Our study indicates that on Venus, due to its larger mass and size compared to Mars, the most relevant atmospheric escape processes of oxygen involve ions and are caused by the interaction with the solar wind. The obtained results indicate that the ratio between H/O escape to space from the Venusian upper atmosphere is about 4, and is in a much better agreement with the stoichiometrically H/O escape ratio of 2:1, which is not the case on Mars. However, a detailed analysis of the outflow of ions from the Venus upper atmosphere by the ASPERA-4 and VEX-MAG instruments aboard Venus Express will lead to more accurate atmospheric loss estimations and a better understanding of the planet's water inventory. (c) 2006 Elsevier Ltd. All rights reserved.


Доп.точки доступа:
Lammer, H.; Lichtenegger, H.I.M.; Biernat, H.K.; Erkaev, N.V.; Еркаев, Николай Васильевич; Arshukova, I.L.; Kolb, C.; Gunell, H.; Lukyanov, A.; Holmstrom, M.; Barabash, S.; Zhang, T.L.; Baumjohann, W.

    Determining the mass loss limit for close-in exoplanets: what can we learn from transit observations?
[Text] / H. . Lammer [et al.] // Astron. Astrophys. - 2009. - Vol. 506, Is. 1. - P399-410, DOI 10.1051/0004-6361/200911922. - Cited References: 46. - The authors thank the anonymous referee for constructive comments and suggestions which helped to improve the paper. H. Lammer, P. Odert, M. Leitzinger, M. L. Khodachenko and A. Hanslmeier gratefully acknowledge the Austrian Fonds zur Forderung der wissenschaftlichen Forschung (FWF grant P19446) for supporting this project. M. Panchenko and M. L. Khodachenko acknowledge also the Austrian Fonds zur Forderung der wissenschaftlichen Forschung (project P20680-N16). H. Lammer, H. I. M. Lichtenegger, H. K. Biernat, Yu. N. Kulikov and N. V. Erkaev thank the AAS "Verwaltungsstelle fur Auslandsbeziehungen" and the RAS. H. Lammer, H. I. M. Lichtenegger, M. L. Khodachenko and Yu. N. Kulikov acknowledge support from the Helmholtz-Gemeinschaft as this research has been supported by the Helmholtz Association through the research alliance "Planetary Evolution and Life". H. Lammer, M. L. Khodachenko, T. Penz, and Yu. N. Kulikov also acknowledge the International Space Science Institute (ISSI; Bern, Switzerland) and the ISSI teams "Evolution of Habitable Planets" and "Evolution of Exoplanet Atmospheres and their Characterization". H. K. Biernat acknowledges additional support due to the Austrian Science Fund under project P20145-N16. The authors also acknowledge fruitful discussions during various meetings related to the Europlanet N2 activities as well as within the N2 Exoplanet discipline working group DWG 7. T. Penz and G. Micela acknowledge support by the Marie Curie Fellowship Contract No. MTKD-CT-2004-002769 of the project "The influence of stellar high radiation on planetary atmospheres". The authors also thank the Austrian Ministry bm:bwk and ASA for funding the CoRoT project. . - ISSN 0004-6361
РУБ Astronomy & Astrophysics

Аннотация: Aims. We study the possible atmospheric mass loss from 57 known transiting exoplanets around F, G, K, and M-type stars over evolutionary timescales. For stellar wind induced mass loss studies, we estimate the position of the pressure balance boundary between Coronal Mass Ejection (CME) and stellar wind ram pressures and the planetary ionosphere pressure for non- or weakly magnetized gas giants at close orbits. Methods. The thermal mass loss of atomic hydrogen is calculated by a mass loss equation where we consider a realistic heating efficiency, a radius-scaling law and a mass loss enhancement factor due to stellar tidal forces. The model takes into account the temporal evolution of the stellar EUV flux by applying power laws for F, G, K, and M-type stars. The planetary ionopause obstacle, which is an important factor for ion pick-up escape from non- or weakly magnetized gas giants is estimated by applying empirical power-laws. Results. By assuming a realistic heating efficiency of about 10-25% we found that WASP-12b may have lost about 6-12% of its mass during its lifetime. A few transiting low density gas giants at similar orbital location, like WASP-13b, WASP-15b, CoRoT-1b or CoRoT-5b may have lost up to 1-4% of their initial mass. All other transiting exoplanets in our sample experience negligible thermal loss (<= 1%) during their lifetime. We found that the ionospheric pressure can balance the impinging dense stellar wind and average CME plasma flows at distances which are above the visual radius of "Hot Jupiters", resulting in mass losses <2% over evolutionary timescales. The ram pressure of fast CMEs cannot be balanced by the ionospheric plasma pressure for orbital distances between 0.02-0.1 AU. Therefore, collisions of fast CMEs with hot gas giants should result in large atmospheric losses which may influence the mass evolution of gas giants with masses
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Доп.точки доступа:
Lammer, H.; Odert, P.; Leitzinger, M.; Khodachenko, M.L.; Panchenko, M.; Kulikov, Y.N.; Zhang, T.L.; Lichtenegger, H.I.M.; Erkaev, N.V.; Еркаев, Николай Васильевич; Wuchterl, G.; Micela, G.; Penz, T.; Biernat, H.K.; Weingrill, J.; Steller, M.; Ottacher, H.; Hasiba, J.; Hanslmeier, A.; Austrian Fonds zur Forderung der wissenschaftlichen Forschung [P19446, P20680-N16]; Helmholtz Association; Austrian Science Fund [P20145-N16]; "The influence of stellar high radiation on planetary atmospheres" [MTKD-CT-2004-002769]

    Results of analysis of human impact on environment using the time series of vegetation satellite images around large industrial centers
[Text] / A. Shevyrnogov [et al.] // Adv. Space Res. - 2008. - Vol. 41, Is. 1. - P36-40, DOI 10.1016/j.asr.2007.02.008. - Cited References: 7 . - ISSN 0273-1177
РУБ Astronomy & Astrophysics + Geosciences, Multidisciplinary + Meteorology & Atmospheric Sciences

Кл.слова (ненормированные):
remote sensing -- industrial wastes -- vegetation index -- vegetation dynamics

Аннотация: The paper shows the efficiency of an application of the vegetation index image time series to determine long-term vegetation dynamics. The influence of large industrial centers of Siberia on the near-by vegetation is demonstrated. The analysis of the data shows that the influence of industrial waste is stronger in the Siberian North. These regions are characterized by critical conditions for vegetation existence. In the south of the Krasnoyarsk region, human impact is also important, but the possibility of vegetation self-rehabilitation is higher. The present-day economic situation in Russia is unique, with a temporary abrupt fall of industrial production and its following increase. Thus, we managed to analyze the degree of human impact on the environment within a relatively short-time interval. (C) 2007 Published by Elsevier Ltd on behalf of COSPAR.


Доп.точки доступа:
Shevyrnogov, A.; Vysotskaya, G.; Высоцкая, Галина Степановна; Sukhinin, A.; Frolikova, O.; Tchernetsky, M.

    Construction of Confidence Limits for the Probability Density Function on the Basis of Nonparametric Estimation of the Function
[Text] / A. V. Lapko, V. A. Lapko // Meas. Tech. - 2014. - Vol. 56, Is. 12. - P1354-1357, DOI 10.1007/s11018-014-0381-8. - Cited References: 9 . - ISSN 0543-1972. - ISSN 1573-8906
РУБ Engineering, Multidisciplinary + Instruments & Instrumentation

Аннотация: A technique for the construction of confidence limits for the probability density function is proposed and its efficiency as a function of the probabilistic characteristics of the procedure of decomposition of the domain of variation of the random variable is investigated.

WOS

Держатели документа:
[Lapko, A. V.] Russian Acad Sci IVM SO RAN, Inst Computat Modeling, Siberian Branch, Krasnoyarsk, Russia
[Lapko, V. A.] Academician Reshetnev Siberian State Aerosp Univ, Krasnoyarsk, Russia
ИВМ СО РАН

Доп.точки доступа:
Lapko, V.A.; Лапко, Василий Александрович; Лапко, Александр Васильевич

    Stellar wind interaction and pick-up ion escape of the Kepler-11 "super-Earths"
[Text] / K. G. Kislyakova [et al.] // Astron. Astrophys. - 2014. - Vol. 562. - Ст. A116, DOI 10.1051/0004-6361/201322933. - Cited References: 45. - K.G. Kislyakova, C.P. Johnstone, M.L. Khodachenko, H. Lammer, T. Luftinger and M. Gudel acknowledge the support by the FWF NFN project S116601-N16 "Pathways to Habitability: From Disks to Active Stars, Planets and Life", and the related EWE NFN subprojects, S116 604-N16 "Radiation & Wind Evolution from T Tauri Phase to ZAMS and Beyond". 5116 606-N16 "Magnetospheric Electrodynamics of Exoplanets", and S116607-N16 "Particle/Radiative Interactions with Upper Atmospheres of Planetary Bodies Under Extreme Stellar Conditions". T. Luftinger acknowledges also the support by the FWF project P19962-N16. K. G. Kislyakova, H. Lammer, and P. Odert thank also the Helmholtz Alliance project "Planetary Evolution and Life". P. Odert acknowledges support from the EWE project P22950-N16. The authors also acknowledge support from the EU FP7 project IMPEx (No.262863) and the EUROPLANET-RI projects, JRA3/EMDAF and the Na2 science WG5. N. V. Erkaev acknowledges support by the RFBR grant No 12-05-00152-a. Finally, the authors thank the International Space Science Institute (ISSI) in Bern, and the ISSI team "Characterizing stellar- and exoplanetary environments". This research was conducted using resources provided by the Swedish National Infrastructure for Computing (SNIC) at the High Performance Computing Center North (HPC2N). The authors thank also the anonymous referee for his useful comments. . - ISSN 0004-6361. - ISSN 1432-0746
РУБ Astronomy & Astrophysics

Аннотация: Aims. We study the interactions between stellar winds and the extended hydrogen-dominated upper atmospheres of planets. We estimate the resulting escape of planetary pick-up ions from the five "super-Earths" in the compact Kepler-11 system and compare the escape rates with the efficiency of the thermal escape of neutral hydrogen atoms. Methods. Assuming the stellar wind of Kepler-11 is similar to the solar wind, we use a polytropic ID hydrodynamic wind model to estimate the wind properties at the planetary orbits. We apply a direct simulation Monte Carlo model to model the hydrogen coronae and the stellar wind plasma interaction around Kepler-11b-f within a realistic expected heating efficiency range of 15-40%. The same model is used to estimate the ion pick-up escape from the XUV heated and hydrodynamically extended upper atmospheres of Kepler-11b-f. From the interaction model, we study the influence of possible magnetic moments, calculate the charge exchange and photoionization production rates of planetary ions, and estimate the loss rates of pick-up H+ ions for all five planets. We compare the results between the five "super-Earths" and the thermal escape rates of the neutral planetary hydrogen atoms. Results. Our results show that a huge neutral hydrogen corona is formed around the planet for all Kepler-11b-f exoplanets. The non-symmetric form of the corona changes from planet to planet and is defined mostly by radiation pressure and gravitational effects. Non-thermal escape rates of pick-up ionized hydrogen atoms for Kepler-11 "super-Earths" vary between similar to.6.4x10(30) s(-1) and similar to 4.1 x10(31) s(-1), depending on the planet's orbital location and assumed heating efficiency. These values correspond to non-thermal mass loss rates of similar to 1.07 x 10(7) g s(-1) and similar to 6.8 x 10(2) g s(-1) respectively, which is a few percent of the thermal escape rates.

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Доп.точки доступа:
Kislyakova, K.G.; Johnstone, C.P.; Odert, P.; Erkaev, N.V.; Еркаев, Николай Васильевич; Lammer, H.; Luftinger, T.; Holmstrom, M.; Khodachenko, M.L.; Guedel, M.; FWF NFN project [S116601-N16]; EWE NFN subprojects T Tauri Phase [S116 604-N16]; "Magnetospheric Electrodynamics of Exoplanets" [5116 606-N16]; "Particle/Radiative Interactions with Upper Atmospheres of Planetary Bodies Under Extreme Stellar Conditions" [S116607-N16]; FWF project [P19962-N16]; EWE project [P22950-N16]; EU [262863]; EUROPLANET-RI projects [JRA3/EMDAF, Na2 science WG5]; RFBR [12-05-00152-a]

    Effect of data incompleteness on the approximation properties of nonparametric estimation of the two-dimensional probability density of independent random variables
[] / A. V. Lapko, V. A. Lapko // Optoelectron. Instrum. Data Proces. - 2014. - Vol. 50, Is. 1. - P68-74, DOI 10.3103/S8756699014010099 . - ISSN 1934-7944
Аннотация: Asymptotic properties of a nonparametric estimate of the two-dimensional probability density of independent random variables are studied. Based on these results, the dependence of its efficiency on data incompleteness in the initial statistical information is determined. © 2014 Allerton Press, Inc.

Scopus

Держатели документа:
Institute of Computational Modeling, Siberian Branch, Russian Academy of Sciences, Akademgorodok 50, building 44, Krasnoyarsk, 660036, Russian Federation
Reshetnev Siberian State Aerospace University, pr. im. Gazety Krasnoyarskii rabochii 31, Krasnoyarsk, 660014, Russian Federation

Доп.точки доступа:
Lapko, V.A.; Лапко, Василий Александрович; Лапко, Александр Васильевич

    Maximum entropy method in analysis of genetic text and measurement of its information content
/ N. N. Bugaenko, A. N. Gorban, M. G. Sadovsky // Open Systems and Information Dynamics. - 1998. - Vol. 5, Is. 3. - P265-278 . - ISSN 1230-1612

Аннотация: The information capacity in frequency dictionaries of nucleotide sequences is estimated through the efficiency of reconstruction of a longer frequency dictionary from a short one. This reconstruction is performed by the maximum entropy method. Real nucleotide sequences are compared to random ones (with the same composition of nucleotides). Phages genes from NCBI bank were analyzed. The reliable difference of real genetic texts from random sequences is observed for the dictionary length q = 2, 5 and 6.

Scopus

Держатели документа:
Computing Center, Siberian Division, Russian Academy of Sciences, Akademgorodok, Krasnoyarsk, 660036, Russian Federation
Institute of Biophysics, Siberian Division, Russian Academy of Sciences, Akademgorodok, Krasnoyarsk, 660036, Russian Federation
ИВМ СО РАН
ИБФ СО РАН

Доп.точки доступа:
Bugaenko, N.N.; Gorban, A.N.; Горбань, Александр Николаевич; Sadovsky, M.G.; Садовский, Михаил Георгиевич

    Numerical simulation of the dynamics of a liquid crystal in the case of plane strain using GPUs
/ O. V. Sadovskaya // AIP Conference Proceedings. - 2014. - Vol. 1629: 6th International Conference for Promoting the Application of Mathematics in Technical and Natural Sciences, AMiTaNS 2014 (26 June 2014 through 1 July 2014, ) Conference code: 109043. - P303-310, DOI 10.1063/1.4902286 . -
Аннотация: Parallel computational algorithm is worked out for numerical implementation of two-dimensional dynamic model of a liquid crystal, which takes into account the mutual influence of three physical effects - transfer of acoustic energy due to translational motion, viscoelastic rotation of the particles under the action of tangential stresses, anisotropic thermal expansion and compression. The algorithm is based on the Godunov gap decay method, the Ivanov scheme with controlled dissipation of energy and the splitting method with respect to spatial variables. The CUDA technology for computer systems with graphic accelerators is used. Results of computations demonstrating the efficiency of proposed method and algorithm are represented.

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

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

    The effect of heating the aluminum master alloy in the rod form on size of titanium aluminide particles
[Текст] : статья / G. G. Krushenko // Вестник Сибирского государственного аэрокосмического университета им. академика М.Ф. Решетнева. - 2013. - Вып. 3(49). - С. 197-198
   Перевод заглавия: Влияние нагрева алюминиевой прутковой лигатуры на величину частиц алюминида титана
Аннотация: The metal products of machine-building profile manufactured of billets passed through the cycle of melting-crystallization and having microcrystalline structure, demonstrate higher physical-mechanical properties and exploitation characteristics in comparison with the metal products of macro crystalline structure. During the process of melting the refining structure additives are introduced into liquid metal using master alloys for the aim of the structure refinement. In particular, the similar master alloy is the rod aluminum-titanium master alloy containing titanium aluminide particles which are the crystallization centers. It is determined, that the rod heating in the process of its introducing into the liquid metal leads to enlargement of the titanium aluminide particles, that decreases the efficiency of structure refinement. Therefore, in every particular case, it is necessary to optimize the velocity of rod introducing into liquid metal.

РИНЦ


Доп.точки доступа:
Крушенко, Генрих Гаврилович

    Regression estimate of the multidimensional probability density and its properties
/ A. V. Lapko, V. A. Lapko // Optoelectronics, Instrumentation and Data Processing. - 2014. - Vol. 50, Is. 2. - P148-153DOI 10.3103/S875669901402006X . -

Аннотация: A method of synthesis and analysis of regression estimate of the multidimensional probability density under conditions of a large volume of initial statistical data is proposed. Its asymptotic properties are investigated. On this basis, the relationship between the efficiency factor of the proposed estimate and the parameters of the procedure of expansion of initial data is established.

Scopus


Доп.точки доступа:
Lapko, V.A.; Лапко, Василий Александрович; Лапко, Александр Васильевич