[Text] : scientific proceeding / В. П. Шунков, М. Н. Ивко, В. И. Сенашов. - Красноярск : ВЦ СО РАН, 1993. - 64 p. - (Препринт ВЦ СО РАН (Красноярск) ; № 1). - Библиогр. в конце ст. - Б. ц.
Перевод заглавия: Теория групп
Перевод заглавия: Теория групп
Держатели документа:
ИВМ СО РАН : 660036, Красноярск, Академгородок, 50, стр.44
Доп.точки доступа:
Шунков, Владимир Петрович; Ивко, М.Н.; Сенашов, Владимир Иванович; Senashov V.I.
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Group properties and exact solutions of equations for vibrational convection of a binary mixture
[Текст] : статья / I.I. Ryzhkov // Lournal of Applied Mechanics and Technical Physics. - 2011. - Vol. 52, Iss. 4. - p. 560-570DOI 10.1134/S0021894411040080
. -
Аннотация: A model of vibrational convection of a binary mixture with the thermodiffusion effect is considered. The symmetries of model equations are found, depending on the values of physical parameters. A partially invariant solution, which describes separation of the binary mixture in a thermodiffusion column, is constructed and studied. The influence of streamwise vibrations on the flow regime and separation of the mixture is investigated.
Полный текст на сайте правообладателя
Доп.точки доступа:
Stepanova, I.V.; Степанова, Ирина Владимировна; Рыжков, Илья Игоревич
Аннотация: A model of vibrational convection of a binary mixture with the thermodiffusion effect is considered. The symmetries of model equations are found, depending on the values of physical parameters. A partially invariant solution, which describes separation of the binary mixture in a thermodiffusion column, is constructed and studied. The influence of streamwise vibrations on the flow regime and separation of the mixture is investigated.
Полный текст на сайте правообладателя
Доп.точки доступа:
Stepanova, I.V.; Степанова, Ирина Владимировна; Рыжков, Илья Игоревич
On groups with a strongly imbedded subgroup having an almost layer-finite periodic part
/ V.I. Senashov // Ukr. Math. J. - 2012. - Vol. 64, Is. 3. - P433-440, DOI 10.1007/s11253-012-0656-7. - Cited References: 25. - This work was supported by the Russian Foundation for Fundamental Research (grant Nos. 09-01-00395 and 10-01-00509) and the Siberian Federal University ("Elite Mathematics Education at the Siberian Federal University" project).
. - ISSN 0041-5995
Аннотация: We study Shunkov groups with the following condition: the normalizer of any finite nontrivial subgroup has an almost layer-finite periodic part. It is proved that such a group has an almost layer-finite periodic part if it has a strongly imbedded subgroup with almost layer-finite periodic part.
Полный текст
Держатели документа:
ИВМ СО РАН : 660036, Красноярск, Академгородок, 50, стр.44
Доп.точки доступа:
Сенашов, Владимир Иванович
Аннотация: We study Shunkov groups with the following condition: the normalizer of any finite nontrivial subgroup has an almost layer-finite periodic part. It is proved that such a group has an almost layer-finite periodic part if it has a strongly imbedded subgroup with almost layer-finite periodic part.
Полный текст
Держатели документа:
ИВМ СО РАН : 660036, Красноярск, Академгородок, 50, стр.44
Доп.точки доступа:
Сенашов, Владимир Иванович
Group classification for equations of thermodiffusion in binary mixture
/ I.V. Stepanova // Commun. Nonlinear Sci. Numer. Simul. - 2013. - Vol. 18, Is. 6. - P1341-1346, DOI 10.1016/j.cnsns.2012.10.013. - Cited References: 14. - Author thanks Prof. V.K. Andreev for formulation of the problem and attention to the work. This work is supported by the Integrational Grant No 44 and The Ministry of education and science of Russia, project 14.A18.21.2014.
. - 6. - ISSN 1007-5704
РУБ Mathematics, Applied + Mathematics, Interdisciplinary Applications + Mechanics + Physics, Fluids & Plasmas + Physics, Mathematical
Кл.слова (ненормированные):
Lie symmetry analysis -- Group classification -- Equivalence transformations -- Thermodiffusion -- Binary mixture -- Transport coefficients
Аннотация: Group classification problem is solved for equations of motion of a binary mixture under the buoyancy force and thermodiffusion effect. These equations are parameterized by five arbitrary functions of two arguments. The admissible Lie symmetry algebras of generators are found depending on arbitrary elements. These results are useful for analytical and numerical modeling of the convection in binary mixtures. (C) 2012 Elsevier B. V. All rights reserved.
Доп.точки доступа:
Stepanova, I.V.; Степанова, Ирина Владимировна
Кл.слова (ненормированные):
Lie symmetry analysis -- Group classification -- Equivalence transformations -- Thermodiffusion -- Binary mixture -- Transport coefficients
Аннотация: Group classification problem is solved for equations of motion of a binary mixture under the buoyancy force and thermodiffusion effect. These equations are parameterized by five arbitrary functions of two arguments. The admissible Lie symmetry algebras of generators are found depending on arbitrary elements. These results are useful for analytical and numerical modeling of the convection in binary mixtures. (C) 2012 Elsevier B. V. All rights reserved.
Доп.точки доступа:
Stepanova, I.V.; Степанова, Ирина Владимировна
Self-similar degeneration of the turbulent wake behind a body towed in a passively stratified medium
/ O.V. Kaptsov [et al.] // J. Appl. Mech. Tech. Phys. - 2012. - Vol. 53, Is. 5. - pp. 672-678, DOI 10.1134/S0021894412050069. - Cited References: 16. - This work was supported by the Russian Foundation for Basic Research (Grants Nos. 10-01-00435-a and 11-01-09368-mob_z), by the Council on Grants of the President of the Russian Federation for Support of Leading Scientific Schools (Grants Nos. NSh-544.2012.1 and NSh-6293.2012.9), and by the Russian Academy of Sciences (Integration Project No. 103 (Siberian, Far-East, and Ural Branches)).
. - 7. - ISSN 0021-8944
РУБ Mechanics + Physics, Applied
Аннотация: A mathematical model of the far turbulent wake behind a towed body in a passively stratified medium, based on the known semi-empirical e-E > model of turbulence, is considered. A grouptheoretical analysis of the model is performed. With the help of the method of B-determining equations, the model is reduced to a system of ordinary differential equations, which is solved numerically. The resultant solution is compared with a self-similar solution obtained by direct numerical integration of the differential equations at large distances from the body.
Доп.точки доступа:
Kaptsov, O.V.; Капцов, Олег Викторович; Fomina, A.V.; Chernykh, G.G.; Schmidt, A.V.; Шмидт, Алексей Владимирович
Рубрики:
DYNAMICS
Кл.слова (ненормированные):
mathematical model of the far turbulent wake -- towed body of revolution -- passively stratified medium -- e-epsilon model of turbulence -- group-theoretical analysis -- method of B-determining equations -- self-similar degeneration
DYNAMICS
Кл.слова (ненормированные):
mathematical model of the far turbulent wake -- towed body of revolution -- passively stratified medium -- e-epsilon model of turbulence -- group-theoretical analysis -- method of B-determining equations -- self-similar degeneration
Аннотация: A mathematical model of the far turbulent wake behind a towed body in a passively stratified medium, based on the known semi-empirical e-E > model of turbulence, is considered. A grouptheoretical analysis of the model is performed. With the help of the method of B-determining equations, the model is reduced to a system of ordinary differential equations, which is solved numerically. The resultant solution is compared with a self-similar solution obtained by direct numerical integration of the differential equations at large distances from the body.
Доп.точки доступа:
Kaptsov, O.V.; Капцов, Олег Викторович; Fomina, A.V.; Chernykh, G.G.; Schmidt, A.V.; Шмидт, Алексей Владимирович
Comparative analysis of phytoplankton of the Baikal and Khanka lakes
[Text] / L.A. Shchur, N.A. Bondarenko // Hydrobiological Journal. - 2012. - Vol. 48, Is. 3. - pp. 14-23, DOI 10.1615/HydrobJ.v48.i3.20
. - ISSN 0018-8166
Кл.слова (ненормированные):
Biomass -- Numbers -- Phytoplankton -- Primary and specific production -- alga -- biomass -- community composition -- comparative study -- dominance -- environmental conditions -- functional group -- hydrological regime -- lake ecosystem -- phytoplankton -- primary production -- vegetation structure -- Khanka Lake -- Lake Baikal -- Russian Federation -- algae
Аннотация: The structure and production potential of phytoplankton were studied in two large lakes of Asia, including the Baikal and Khanka lakes differing in their hydrological conditions. It has been found that the studied algae flora is saturated. The environmental conditions in the lakes are rather favorable to the development of algae. The functional characteristics of phytoplankton depended mainly on the regime of illumination, dimensional composition of algae, intensity of their development, vegetation stage, and also on the peculiarities of dominant forms biology. В© 2012 Begell House, Inc.
Scopus
Доп.точки доступа:
Shchur, L.A.; Щур, Людмила Александровна; Bondarenko, N.A.
Кл.слова (ненормированные):
Biomass -- Numbers -- Phytoplankton -- Primary and specific production -- alga -- biomass -- community composition -- comparative study -- dominance -- environmental conditions -- functional group -- hydrological regime -- lake ecosystem -- phytoplankton -- primary production -- vegetation structure -- Khanka Lake -- Lake Baikal -- Russian Federation -- algae
Аннотация: The structure and production potential of phytoplankton were studied in two large lakes of Asia, including the Baikal and Khanka lakes differing in their hydrological conditions. It has been found that the studied algae flora is saturated. The environmental conditions in the lakes are rather favorable to the development of algae. The functional characteristics of phytoplankton depended mainly on the regime of illumination, dimensional composition of algae, intensity of their development, vegetation stage, and also on the peculiarities of dominant forms biology. В© 2012 Begell House, Inc.
Scopus
Доп.точки доступа:
Shchur, L.A.; Щур, Людмила Александровна; Bondarenko, N.A.
On shunkov's groups with involutions
/ V. L. Senashov // Advances in Modelling and Analysis A. - 2012. - Vol. 49, Is. 1-2. - P1-14
. - ISSN 1258-5769
Кл.слова (ненормированные):
Finiteness condition -- Infinite group -- Involution -- Finiteness condition -- Infinite groups -- Involution -- Strongly embedded subgroup -- Computational methods -- Computer simulation -- Combinatorial circuits
Аннотация: Infinite Shunkov's groups are studied under the condition that a normalizer of any finite non-unit subgroup has an almost layer-finite periodic part. It has been proved that Shunkov's group satisfies this condition with strongly embedded subgroup possessing non-Chernikov's almost layer-finite periodic part has an almost layer-finite periodic part.
Scopus
Держатели документа:
Institute of Computational Modelling, Siberian Division of Russian Academy of Sciences, Akademgorodok, Krasnoyarsk, Russian Federation
Доп.точки доступа:
Senashov, V.L.
Кл.слова (ненормированные):
Finiteness condition -- Infinite group -- Involution -- Finiteness condition -- Infinite groups -- Involution -- Strongly embedded subgroup -- Computational methods -- Computer simulation -- Combinatorial circuits
Аннотация: Infinite Shunkov's groups are studied under the condition that a normalizer of any finite non-unit subgroup has an almost layer-finite periodic part. It has been proved that Shunkov's group satisfies this condition with strongly embedded subgroup possessing non-Chernikov's almost layer-finite periodic part has an almost layer-finite periodic part.
Scopus
Держатели документа:
Institute of Computational Modelling, Siberian Division of Russian Academy of Sciences, Akademgorodok, Krasnoyarsk, Russian Federation
Доп.точки доступа:
Senashov, V.L.
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.
Рубрики:
FRESH-WATER ECOSYSTEMS
OF-THE-ART
DAPHNIA POPULATION-DYNAMICS
TROPHIC STATE INDICATORS
PREDATOR-PREY SYSTEM
CAUSES REGIME SHIFTS
LIBRARY SALMO-OO
SHALLOW LAKES
CLIMATE-CHANGE
SUBMERGED MACROPHYTES
Кл.слова (ненормированные):
Aquatic -- Food web dynamics -- Plankton -- Nutrients -- Spatial -- Lake -- Freshwater -- Marine -- Community -- Population -- Hydrology -- Eutrophication -- Global change -- Climate warming -- Fisheries -- Biodiversity -- Management -- Mitigation -- Adaptive processes -- Non-linear dynamics -- Analysis -- Bifurcation -- Understanding -- Prediction -- Model limitations -- Model integration
FRESH-WATER ECOSYSTEMS
OF-THE-ART
DAPHNIA POPULATION-DYNAMICS
TROPHIC STATE INDICATORS
PREDATOR-PREY SYSTEM
CAUSES REGIME SHIFTS
LIBRARY SALMO-OO
SHALLOW LAKES
CLIMATE-CHANGE
SUBMERGED MACROPHYTES
Кл.слова (ненормированные):
Aquatic -- Food web dynamics -- Plankton -- Nutrients -- Spatial -- Lake -- Freshwater -- Marine -- Community -- Population -- Hydrology -- Eutrophication -- Global change -- Climate warming -- Fisheries -- Biodiversity -- Management -- Mitigation -- Adaptive processes -- Non-linear dynamics -- Analysis -- Bifurcation -- Understanding -- Prediction -- Model limitations -- Model integration
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.
Diatoms of some water bodies in northeastern West Siberia. Communication 1. Centrophyceae
[Text] / S.I. Genkal, L.A. Shchur, M.I. Yarushina // Contemp. Probl. Ecol. - 2010. - Vol. 3, Is. 4. - pp. 386-394, DOI 10.1134/S1995425510040041. - Cited References: 34. - The work was supported by Russian Foundation for Basic Research, grant no. 06-04-48173.
. - ISSN 1995-4255
РУБ Ecology
Аннотация: In the phytoplankton of northeastern West Siberian water bodies, Bacillariophyta were a dominant group of the 7 most abundant algal divisions, with the occurrence of the members of the class Centrophyceae varying from 27 to 100%. Scanning electron microscopy revealed complete species composition of the class Centrophyceae that dominates the phytoplankton of Lake Delingde, the Delingde and Bol'shaya Kheta rivers (Aulacoseira, 3 species; Cyclostephanos, 1; Cyclotella, 5; Discostella, 1; Melosira, 1; Pliocaenicus, 1; Puncticulata, 1; Stephanodiscus, 6). The phytoplankton of the class Centrophyceae in the Taz River now has a new member, Puncticulata radiosa. New species of the genus Cyclotella in West Siberian algal flora were revealed: C. arctica, C. comensis, and C. vorticosa. The findings helped more precisely define the ranges of the rare taxa and add new diagnostic features to the diagnoses of C. comensis and Stephanodiscus invisitatus.
Доп.точки доступа:
Genkal, S.I.; Генкал С.И.; Shchur, L.A.; Щур, Людмила Александровна; Yarushina, M.I.
Аннотация: In the phytoplankton of northeastern West Siberian water bodies, Bacillariophyta were a dominant group of the 7 most abundant algal divisions, with the occurrence of the members of the class Centrophyceae varying from 27 to 100%. Scanning electron microscopy revealed complete species composition of the class Centrophyceae that dominates the phytoplankton of Lake Delingde, the Delingde and Bol'shaya Kheta rivers (Aulacoseira, 3 species; Cyclostephanos, 1; Cyclotella, 5; Discostella, 1; Melosira, 1; Pliocaenicus, 1; Puncticulata, 1; Stephanodiscus, 6). The phytoplankton of the class Centrophyceae in the Taz River now has a new member, Puncticulata radiosa. New species of the genus Cyclotella in West Siberian algal flora were revealed: C. arctica, C. comensis, and C. vorticosa. The findings helped more precisely define the ranges of the rare taxa and add new diagnostic features to the diagnoses of C. comensis and Stephanodiscus invisitatus.
Доп.точки доступа:
Genkal, S.I.; Генкал С.И.; Shchur, L.A.; Щур, Людмила Александровна; Yarushina, M.I.
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.
Полный текст
Держатели документа:
ИВМ СО РАН : 660036, Красноярск, Академгородок, 50, стр.44
Доп.точки доступа:
Садовский, Михаил Георгиевич
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.
Полный текст
Держатели документа:
ИВМ СО РАН : 660036, Красноярск, Академгородок, 50, стр.44
Доп.точки доступа:
Садовский, Михаил Георгиевич
Symmetry Analysis of Equations for Convection
[Текст] : статья / I.I. Ryzhkov // Journal of Siberian Federal University. Mathematics & Physics = Журнал Сибирского федерального университета. Математика и физика. - 2008. - Т. 1, № 4. - С. 410-431
Кл.слова (ненормированные):
Lie symmetry group -- equivalence transformation -- binary mixture -- convection -- Soret and Dufour
Аннотация: The differential equations describing convection in binary mixture with Soret and Dufour effects are considered. The symmetry classification of these equations with respect to the constant parameters is made. It is shown that a generator producing equivalence transformations of constants is defined accurately up to a factor arbitrarily depending on these constants. The equivalence group admitted by the governing equations is calculated. Using this group, a transformation connecting the systems with and without Soret and Dufour terms is derived. In pure Soret case, it reduces to a linear change of temperature and concentration. The presence of Dufour effect requires an additional change of thermal diffusivity and diffusion coefficient. A scheme for reducing an initial and boundary value problem for Soret–Dufour equations to a problem for the system without these effects is proposed.
Полный текст на сайте журнала
Держатели документа:
ИВМ СО РАН : 660036, Красноярск, Академгородок, 50, стр.44
Доп.точки доступа:
Рыжков, Илья Игоревич
Кл.слова (ненормированные):
Lie symmetry group -- equivalence transformation -- binary mixture -- convection -- Soret and Dufour
Аннотация: The differential equations describing convection in binary mixture with Soret and Dufour effects are considered. The symmetry classification of these equations with respect to the constant parameters is made. It is shown that a generator producing equivalence transformations of constants is defined accurately up to a factor arbitrarily depending on these constants. The equivalence group admitted by the governing equations is calculated. Using this group, a transformation connecting the systems with and without Soret and Dufour terms is derived. In pure Soret case, it reduces to a linear change of temperature and concentration. The presence of Dufour effect requires an additional change of thermal diffusivity and diffusion coefficient. A scheme for reducing an initial and boundary value problem for Soret–Dufour equations to a problem for the system without these effects is proposed.
Полный текст на сайте журнала
Держатели документа:
ИВМ СО РАН : 660036, Красноярск, Академгородок, 50, стр.44
Доп.точки доступа:
Рыжков, Илья Игоревич
Magnetic double-gradient instability and flapping waves in a current sheet
[Text] / N. V. Erkaev, V. S. Semenov, H. K. Biernat // Phys. Rev. Lett. - 2007. - Vol. 99, Is. 23. - Ст. 235003, DOI 10.1103/PhysRevLett.99.235003. - Cited References: 10
. - ISSN 0031-9007
РУБ Physics, Multidisciplinary
Аннотация: A new kind of magnetohydrodynamic instability and waves are analyzed for a current sheet in the presence of a small normal magnetic field component varying along the sheet. These waves and instability are related to the existence of two gradients of the tangential (B(tau)) and normal (B(n)) magnetic field components along the normal (del(n)B(tau)) and tangential (del(tau)B(n)) directions with respect to the current sheet. The current sheet can be stable or unstable if the multiplication of two magnetic gradients is positive or negative. In the stable region, the kinklike wave mode is interpreted as so-called flapping waves observed in Earth's magnetotail current sheet. The kink wave group velocity estimated for the Earth's current sheet is of the order of a few tens of kilometers per second. This is in good agreement with the observations of the flapping motions of the magnetotail current sheet.
Доп.точки доступа:
Erkaev, N.V.; Еркаев, Николай Васильевич; Semenov, V.S.; Biernat, H.K.
Аннотация: A new kind of magnetohydrodynamic instability and waves are analyzed for a current sheet in the presence of a small normal magnetic field component varying along the sheet. These waves and instability are related to the existence of two gradients of the tangential (B(tau)) and normal (B(n)) magnetic field components along the normal (del(n)B(tau)) and tangential (del(tau)B(n)) directions with respect to the current sheet. The current sheet can be stable or unstable if the multiplication of two magnetic gradients is positive or negative. In the stable region, the kinklike wave mode is interpreted as so-called flapping waves observed in Earth's magnetotail current sheet. The kink wave group velocity estimated for the Earth's current sheet is of the order of a few tens of kilometers per second. This is in good agreement with the observations of the flapping motions of the magnetotail current sheet.
Доп.точки доступа:
Erkaev, N.V.; Еркаев, Николай Васильевич; Semenov, V.S.; Biernat, H.K.
MHD aspect of current sheet oscillations related to magnetic field gradients
[Text] / N. V. Erkaev [et al.] // Ann. Geophys. - 2009. - Vol. 27, Is. 1. - P417-425. - Cited References: 24. - We thank V. Sergeev for fruitful discussions and help in preparation of the manuscript. This work is supported by RFBR grants N07-05-00776-a, N 07-05-00135, by SFU grant N 10, by Programs 2.16 and 16.3 of RAS, and by project P20341-N16 from the Austrian " Fonds zur Forderung der wissenschaftlichen Forschung", and also by project I.2/04 from "Osterreichischer Austauschdienst".
. - ISSN 0992-7689
РУБ Astronomy & Astrophysics + Geosciences, Multidisciplinary + Meteorology & Atmospheric Sciences
Аннотация: One-fluid ideal MHD model is applied for description of current sheet flapping disturbances appearing due to a gradient of the normal magnetic field component. The wave modes are studied which are associated to the flapping waves observed in the Earth's magnetotail current sheet. In a linear approximation, solutions are obtained for model profiles of the electric current and plasma densities across the current sheet, which are described by hyperbolic functions. The flapping eigenfrequency is found as a function of wave number. For the Earth's magnetotail conditions, the estimated wave group speed is of the order of a few tens kilometers per second. The current sheet can be stable or unstable in dependence on the direction of the gradient of the normal magnetic field component. The obtained dispersion function is used for calculation of the flapping wave disturbances, which are produced by the given initial Gaussian perturbation at the center of the current sheet and propagating towards the flanks. The propagating flapping pulse has a smooth leading front, and a small scale oscillating trailing front, because the short wave oscillations propagate much slower than the long wave ones.
Доп.точки доступа:
Erkaev, N.V.; Еркаев, Николай Васильевич; Semenov, V.S.; Kubyshkin, I.V.; Kubyshkina, M.V.; Biernat, H.K.; RFBR [N07-05-00776-a, N 07-05-00135]; SFU [N 10]; RAS [2.16, 16.3]; Austrian " Fonds zur Forderung der wissenschaftlichen Forschung" [P20341-N16]; Osterreichischer Austauschdienst [I.2/04]
Рубрики:
MAGNETOTAIL CURRENT SHEET
ION KINK INSTABILITY
PLASMA SHEET
CLUSTER
RECONNECTION
Кл.слова (ненормированные):
Magnetospheric physics -- Magnetotail -- MHD waves and instabilities -- Plasma sheet
MAGNETOTAIL CURRENT SHEET
ION KINK INSTABILITY
PLASMA SHEET
CLUSTER
RECONNECTION
Кл.слова (ненормированные):
Magnetospheric physics -- Magnetotail -- MHD waves and instabilities -- Plasma sheet
Аннотация: One-fluid ideal MHD model is applied for description of current sheet flapping disturbances appearing due to a gradient of the normal magnetic field component. The wave modes are studied which are associated to the flapping waves observed in the Earth's magnetotail current sheet. In a linear approximation, solutions are obtained for model profiles of the electric current and plasma densities across the current sheet, which are described by hyperbolic functions. The flapping eigenfrequency is found as a function of wave number. For the Earth's magnetotail conditions, the estimated wave group speed is of the order of a few tens kilometers per second. The current sheet can be stable or unstable in dependence on the direction of the gradient of the normal magnetic field component. The obtained dispersion function is used for calculation of the flapping wave disturbances, which are produced by the given initial Gaussian perturbation at the center of the current sheet and propagating towards the flanks. The propagating flapping pulse has a smooth leading front, and a small scale oscillating trailing front, because the short wave oscillations propagate much slower than the long wave ones.
Доп.точки доступа:
Erkaev, N.V.; Еркаев, Николай Васильевич; Semenov, V.S.; Kubyshkin, I.V.; Kubyshkina, M.V.; Biernat, H.K.; RFBR [N07-05-00776-a, N 07-05-00135]; SFU [N 10]; RAS [2.16, 16.3]; Austrian " Fonds zur Forderung der wissenschaftlichen Forschung" [P20341-N16]; Osterreichischer Austauschdienst [I.2/04]
On Mazurov triples of the sporadic group B and Hamiltonian cycles of the Cayley graph
[Text] : статья / A. I. Makosi, A. V. Timofeenko // Discrete Mathematics and Applications. - 2008. - Vol. 18, Iss. 2. - p. 199-205, DOI 10.1515/DMA.2008.016
. - ISSN 0924-9265
Аннотация: A system of generators of a group consisting of three involutions, two of which commute, is called a Mazurov triple. We describe algorithms for finding in an explicit form the Mazurov triples of one of the sporadic Monsters, the finite simple group B, and for constructing a Hamiltonian cycle in the Cayley graph of the finite group with Mazurov triple. We give examples of Hamiltonian cycles in the Cayley graphs of some groups.
Доп.точки доступа:
Timofeenko, A.V.; Тимофеенко, Алексей Викторович
Аннотация: A system of generators of a group consisting of three involutions, two of which commute, is called a Mazurov triple. We describe algorithms for finding in an explicit form the Mazurov triples of one of the sporadic Monsters, the finite simple group B, and for constructing a Hamiltonian cycle in the Cayley graph of the finite group with Mazurov triple. We give examples of Hamiltonian cycles in the Cayley graphs of some groups.
Доп.точки доступа:
Timofeenko, A.V.; Тимофеенко, Алексей Викторович
New Classes of Infinite Groups
[Text] : статья / V. I. Senashov, V. P. Shunkov // Mashhad R. J. Math. Sci. - 2008. - Vol. 1, № 1. - p. 23–40
Кл.слова (ненормированные):
Ø-groups -- involution -- Frobenius group -- Chernikov groups -- quasi cyclic groups
Аннотация: In this article, we consider some new classes of groups, namely, Mp-groups, T0-groups,Ø-groups,Ø0-groups, groups with finitely embedded involution, which were appeared at the end of twenties century. These classes of infinite groups with finiteness conditions were introduced by V.P. Shunkov. We give some review of new results on these classes of groups.
Полный текст на сайте журнала
Доп.точки доступа:
Shunkov, V.P.; Шунков, Владимир Петрович; Сенашов, Владимир Иванович
Кл.слова (ненормированные):
Ø-groups -- involution -- Frobenius group -- Chernikov groups -- quasi cyclic groups
Аннотация: In this article, we consider some new classes of groups, namely, Mp-groups, T0-groups,Ø-groups,Ø0-groups, groups with finitely embedded involution, which were appeared at the end of twenties century. These classes of infinite groups with finiteness conditions were introduced by V.P. Shunkov. We give some review of new results on these classes of groups.
Полный текст на сайте журнала
Доп.точки доступа:
Shunkov, V.P.; Шунков, Владимир Петрович; Сенашов, Владимир Иванович
Law of the Minimum paradoxes
[Text] : статья / A. N. Gorban [et al.] // Bulletin of Mathematical Biology. - 2011. - Vol. 73, Iss. 9. - p. 2013-2044DOI 10.1007/s11538-010-9597-1
. -
Аннотация: The “Law of the Minimum” states that growth is controlled by the scarcest resource (limiting factor). This concept was originally applied to plant or crop growth (Justus von Liebig, 1840, Salisbury, Plant physiology, 4th edn., Wadsworth, Belmont, 1992) and quantitatively supported by many experiments. Some generalizations based on more complicated “dose-response” curves were proposed. Violations of this law in natural and experimental ecosystems were also reported. We study models of adaptation in ensembles of similar organisms under load of environmental factors and prove that violation of Liebig’s law follows from adaptation effects. If the fitness of an organism in a fixed environment satisfies the Law of the Minimum then adaptation equalizes the pressure of essential factors and, therefore, acts against the Liebig’s law. This is the the Law of the Minimum paradox: if for a randomly chosen pair “organism–environment” the Law of the Minimum typically holds, then in a well-adapted system, we have to expect violations of this law. For the opposite interaction of factors (a synergistic system of factors which amplify each other), adaptation leads from factor equivalence to limitations by a smaller number of factors. For analysis of adaptation, we develop a system of models based on Selye’s idea of the universal adaptation resource (adaptation energy). These models predict that under the load of an environmental factor a population separates into two groups (phases): a less correlated, well adapted group and a highly correlated group with a larger variance of attributes, which experiences problems with adaptation. Some empirical data are presented and evidences of interdisciplinary applications to econometrics are discussed.
Полный текст на сайте правообладателя
Доп.точки доступа:
Gorban, A.N.; Горбань, Александр Николаевич; Pokidysheva, L.I.; Smirnova, E.V.; Tyukina, T.A.
Аннотация: The “Law of the Minimum” states that growth is controlled by the scarcest resource (limiting factor). This concept was originally applied to plant or crop growth (Justus von Liebig, 1840, Salisbury, Plant physiology, 4th edn., Wadsworth, Belmont, 1992) and quantitatively supported by many experiments. Some generalizations based on more complicated “dose-response” curves were proposed. Violations of this law in natural and experimental ecosystems were also reported. We study models of adaptation in ensembles of similar organisms under load of environmental factors and prove that violation of Liebig’s law follows from adaptation effects. If the fitness of an organism in a fixed environment satisfies the Law of the Minimum then adaptation equalizes the pressure of essential factors and, therefore, acts against the Liebig’s law. This is the the Law of the Minimum paradox: if for a randomly chosen pair “organism–environment” the Law of the Minimum typically holds, then in a well-adapted system, we have to expect violations of this law. For the opposite interaction of factors (a synergistic system of factors which amplify each other), adaptation leads from factor equivalence to limitations by a smaller number of factors. For analysis of adaptation, we develop a system of models based on Selye’s idea of the universal adaptation resource (adaptation energy). These models predict that under the load of an environmental factor a population separates into two groups (phases): a less correlated, well adapted group and a highly correlated group with a larger variance of attributes, which experiences problems with adaptation. Some empirical data are presented and evidences of interdisciplinary applications to econometrics are discussed.
Полный текст на сайте правообладателя
Доп.точки доступа:
Gorban, A.N.; Горбань, Александр Николаевич; Pokidysheva, L.I.; Smirnova, E.V.; Tyukina, T.A.
Properties of the solution of the adjoint problem describing the motion of viscous fluids in a tube
[Text] / V. K. Andreev // Differ. Equ. - 2011. - Vol. 47, Is. 5. - P671-680, DOI 10.1134/S0012266111050065. - Cited References: 6. - The research was supported by the Russian Foundation for Basic Research (project no. 08-01-00762) and by Interscience Integration Project 116 of the Siberian Branch of the Russian Academy of Sciences.
. - ISSN 0012-2661
РУБ Mathematics
Аннотация: For the Navier-Stokes equations, we study a solution invariant with respect to a oneparameter group and modeling a nonstationary motion of two viscous fluids in a cylindrical tube; the fluid layer near the tube wall can be viewed as a lubricant. The motion is due to a nonstationary pressure drop. We obtain a priori estimates for the velocities in the layers. We find a stationary state of the system and show that it is the limit state as t - a provided that the pressure gradient in one of the fluids stabilizes with time. We solve the inverse problem of finding the pressure gradients and the velocity field from a known flow rate.
Доп.точки доступа:
Андреев, Виктор Константинович
Аннотация: For the Navier-Stokes equations, we study a solution invariant with respect to a oneparameter group and modeling a nonstationary motion of two viscous fluids in a cylindrical tube; the fluid layer near the tube wall can be viewed as a lubricant. The motion is due to a nonstationary pressure drop. We obtain a priori estimates for the velocities in the layers. We find a stationary state of the system and show that it is the limit state as t - a provided that the pressure gradient in one of the fluids stabilizes with time. We solve the inverse problem of finding the pressure gradients and the velocity field from a known flow rate.
Доп.точки доступа:
Андреев, Виктор Константинович
Symmetries of equations for vibrational convection in binary mixture
[Text] : статья / I. V. Stepanova, I. I. Ryzhkov // Proceedings of 5-th Int. Workshop in Group analysis of differential equations and integrable system. - 2011. - p. 200-206
. - ISBN 978-9963-700-07-3
Аннотация: Dust kinetic Alfven waves (DKAW) instability with Kappa-distributed ions streaming effects have been examined rigorously in a uniform dusty magnetoplasma. A dispersion relation of low-frequency DKAW instability on the dust acoustic velocity branch is obtained in a low-beta Lorentzian plasma. It is found that nonthermality is more effective for dust kinetic Alfven waves in the perpendicular component having finite larmor radius effects. Lorentzian type charging currents are obtained with the aid of Vlasov theory. Effect of different dust parameters on the growth rates of instability are considered. Damping/instability due to dust charge fluctuation is found to be insensitive to the form of the distribution function for DKAW. Possible applications to dusty space plasmas are pointed out.
Сборник трудов на сайте издательства
Держатели документа:
ИВМ СО РАН : 660036, Красноярск, Академгородок, 50, стр.44
Доп.точки доступа:
Ryzhkov, I.I.; Рыжков, Илья Игоревич; Степанова, Ирина Владимировна; International Workshop in Group analysis of differential equations and integrable system(5 ; June 6–10, 2010 ; Protaras)
Аннотация: Dust kinetic Alfven waves (DKAW) instability with Kappa-distributed ions streaming effects have been examined rigorously in a uniform dusty magnetoplasma. A dispersion relation of low-frequency DKAW instability on the dust acoustic velocity branch is obtained in a low-beta Lorentzian plasma. It is found that nonthermality is more effective for dust kinetic Alfven waves in the perpendicular component having finite larmor radius effects. Lorentzian type charging currents are obtained with the aid of Vlasov theory. Effect of different dust parameters on the growth rates of instability are considered. Damping/instability due to dust charge fluctuation is found to be insensitive to the form of the distribution function for DKAW. Possible applications to dusty space plasmas are pointed out.
Сборник трудов на сайте издательства
Держатели документа:
ИВМ СО РАН : 660036, Красноярск, Академгородок, 50, стр.44
Доп.точки доступа:
Ryzhkov, I.I.; Рыжков, Илья Игоревич; Степанова, Ирина Владимировна; International Workshop in Group analysis of differential equations and integrable system(5 ; June 6–10, 2010 ; Protaras)
Mp -groups not containing groups of quaternions
[] / S. N. Kozulin, V. I. Senashov // Russ. Math. - 2014. - Vol. 58, Is. 2. - P13-23, DOI 10.3103/S1066369X14020030
. - ISSN 1066-369X
Аннотация: This paper continues the study of the class of Mp-groups introduced by V. P. Shunkov. We obtain a criterion of nonsimplicity of an infinite group which contains anMp-group and contains no group of quaternions. We also obtain a criterion for an infinite group to be an Mp-group. © 2014 Allerton Press, Inc.
Scopus
Держатели документа:
VTB24 Lizing Joint Stock Ccompany, Daev per. 20, Moscow 107045, Russian Federation
Institute of Computational Modelling, Siberian Branch of the Russian Academy of Sciences, Akademgorodok 50/44, Krasnoyarsk 660036, Russian Federation
Siberian Federal University, 79 Svobodnyi pr. 79, Krasnoyarsk 660041, Russian Federation
Доп.точки доступа:
Kozulin, S.N.; Senashov, V.I.; Сенашов, Владимир Иванович
Аннотация: This paper continues the study of the class of Mp-groups introduced by V. P. Shunkov. We obtain a criterion of nonsimplicity of an infinite group which contains anMp-group and contains no group of quaternions. We also obtain a criterion for an infinite group to be an Mp-group. © 2014 Allerton Press, Inc.
Scopus
Держатели документа:
VTB24 Lizing Joint Stock Ccompany, Daev per. 20, Moscow 107045, Russian Federation
Institute of Computational Modelling, Siberian Branch of the Russian Academy of Sciences, Akademgorodok 50/44, Krasnoyarsk 660036, Russian Federation
Siberian Federal University, 79 Svobodnyi pr. 79, Krasnoyarsk 660041, Russian Federation
Доп.точки доступа:
Kozulin, S.N.; Senashov, V.I.; Сенашов, Владимир Иванович
Group analysis of Three-dimensional equations of an ideal fluid in terms of trajectories and weber potential
[] / D. A. Krasnova // J. Sib. Fed. Univ. Math. Phys. - 2014. - Vol. 7, Is. 1. - P58-67
. - ISSN 1997-1397
Кл.слова (ненормированные):
Defining equa-tions -- Equations of an ideal fluid -- Equivalent transformation -- Lagrangian coordinates
Аннотация: Lie group analysis of equations of an ideal fluid written in variables of trajectories and Weber's potential was conducted. It was shown that the use of volume conserving arbitrary Lagrangian coordinates is in fact an equivalent transformation for the equations. The defining Lie algebra equations for the initial velocity distribution were obtained. The basic Lie group and its extensions were found. © Siberian Federal University. All rights reserved.
Scopus,
РИНЦ
Держатели документа:
Institute of Computational Modelling, Siberian Branch of the Russian Academy of Sciences, Akademgorodok, 50/44, Krasnoyarsk, 660036, Russian Federation
Доп.точки доступа:
Krasnova, D.A.; Краснова Д.А.
Кл.слова (ненормированные):
Defining equa-tions -- Equations of an ideal fluid -- Equivalent transformation -- Lagrangian coordinates
Аннотация: Lie group analysis of equations of an ideal fluid written in variables of trajectories and Weber's potential was conducted. It was shown that the use of volume conserving arbitrary Lagrangian coordinates is in fact an equivalent transformation for the equations. The defining Lie algebra equations for the initial velocity distribution were obtained. The basic Lie group and its extensions were found. © Siberian Federal University. All rights reserved.
Scopus,
РИНЦ
Держатели документа:
Institute of Computational Modelling, Siberian Branch of the Russian Academy of Sciences, Akademgorodok, 50/44, Krasnoyarsk, 660036, Russian Federation
Доп.точки доступа:
Krasnova, D.A.; Краснова Д.А.