[Text] : статья / S. Arcidiacono, J. Mantzaras, I. V. Karlin // Physical review E. - 2008. - Vol. 78. - Ст. 046711, DOI 10.1103/PhysRevE.78.046711
. - ISSN 1539-3755
Аннотация: A lattice Boltzmann model is developed to simulate finite-rate catalytic surface chemistry. Diffusive wall boundary conditions are established to account for catalytic reactions in multicomponent mixtures. Implementation of wall boundary conditions with chemical reactions is based on a general second-order accurate interpolation scheme. Results of lattice Boltzmann simulations for a four-component mixture with a global catalytic methane oxidation reaction in a straight channel are in excellent agreement with a finite volume Navier-Stokes solver in terms of both the flow field and species concentrations.
Держатели документа:
ИВМ СО РАН : 660036, Красноярск, Академгородок, 50, стр.44
Доп.точки доступа:
Mantzaras, J.; Karlin, I.V.; Карлин, Илья Вениаминович
Труды сотрудников ИВМ СО РАН
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Найдено документов в текущей БД: 10
Construction of algorithms for analytical continuation
/ A. M. Fedotov // Vestnik Moskovskogo Universiteta. Ser. 15 Vychislitel'naya Matematika i Kibernetika. - 1995. - Is. 1. - P64-79
. - ISSN 0137-0782
Кл.слова (ненормированные):
Algorithms -- Error analysis -- Mathematical models -- Mathematical operators -- Matrix algebra -- Optimization -- Set theory -- Theorem proving -- Topology -- Uniqueness theorem -- Interpolation
Аннотация: The paper is devoted to the problem of analytical continuation of functions from sets, being within regularity sets, at the presence of errors in predetermination of initial data. The problem of constructing the optimal algorithms of continuation is considered. Estimations for the accuracy and stability of the optimal continuation algorithms are obtained. A new form is proposed of the uniqueness theorem of analytical functions - the theorem of asymptotic uniqueness and self-regularizating algorithms. Causes of computational instability of the analytical continuation problems are elucidated and a method for organization of a computational process with control of computational errors is proposed.
Scopus
Держатели документа:
Vychislitel'nyj Tsentr SO RAN, Krasnoyarsk, Russian Federation
ИВМ СО РАН
Доп.точки доступа:
Fedotov, A.M.; Федотов, Анатолий Михайлович
Кл.слова (ненормированные):
Algorithms -- Error analysis -- Mathematical models -- Mathematical operators -- Matrix algebra -- Optimization -- Set theory -- Theorem proving -- Topology -- Uniqueness theorem -- Interpolation
Аннотация: The paper is devoted to the problem of analytical continuation of functions from sets, being within regularity sets, at the presence of errors in predetermination of initial data. The problem of constructing the optimal algorithms of continuation is considered. Estimations for the accuracy and stability of the optimal continuation algorithms are obtained. A new form is proposed of the uniqueness theorem of analytical functions - the theorem of asymptotic uniqueness and self-regularizating algorithms. Causes of computational instability of the analytical continuation problems are elucidated and a method for organization of a computational process with control of computational errors is proposed.
Scopus
Держатели документа:
Vychislitel'nyj Tsentr SO RAN, Krasnoyarsk, Russian Federation
ИВМ СО РАН
Доп.точки доступа:
Fedotov, A.M.; Федотов, Анатолий Михайлович
Some estimates of the rate of convergence for the cascadic conjugate-gradient method
/ V. V. Shaidurov // Computers and Mathematics with Applications. - 1996. - Vol. 31, Is. 4-5. - P161-171
. - ISSN 0898-1221
Аннотация: The paper deals with a cascadic conjugate-gradient method (shortly called the CCG-algorithm) which was proposed by P. Deuflhard and can be considered as a simpler version of a multigrid (multilevel) method. We define it recurrently for discrete self-adjoint positive-definite problems on a sequence of grids. On the coarsest grid, the linear discrete algebraic system is solved directly. On the finer grids, the system is iteratively solved by the conjugate-gradient method where the starting guess is an interpolation of the approximated solution on the previous grid. Any preconditioning or restriction to coarser grids is not implemented. Nevertheless, the CCG-algorithm has the same optimal property compared to multigrid methods; namely, the algorithm converges with a rate which is independent of the number of unknowns and the number of grids. As an example, this property is proved for elliptic second order Dirichlet problems in two-dimensional, convex, polygonal bounded domains. For ensuring convergence, the number of iterations on each grid level has to increase from finer to coarser grids. The optimal dependence of these numbers is established with respect to the mesh size and the number of unknowns. The theory has been presented in an abstract setting which allows the application to both finite element and finite difference methods. CopyrightВ©1996 Elsevier Science Ltd. All rights reserved.
Scopus
Держатели документа:
Computing Center, Russian Academy of Sciences, Akademgorodok, Krasnoyarsk, 660036, Russian Federation
ИВМ СО РАН
Доп.точки доступа:
Shaidurov, V.V.; Шайдуров, Владимир Викторович
Аннотация: The paper deals with a cascadic conjugate-gradient method (shortly called the CCG-algorithm) which was proposed by P. Deuflhard and can be considered as a simpler version of a multigrid (multilevel) method. We define it recurrently for discrete self-adjoint positive-definite problems on a sequence of grids. On the coarsest grid, the linear discrete algebraic system is solved directly. On the finer grids, the system is iteratively solved by the conjugate-gradient method where the starting guess is an interpolation of the approximated solution on the previous grid. Any preconditioning or restriction to coarser grids is not implemented. Nevertheless, the CCG-algorithm has the same optimal property compared to multigrid methods; namely, the algorithm converges with a rate which is independent of the number of unknowns and the number of grids. As an example, this property is proved for elliptic second order Dirichlet problems in two-dimensional, convex, polygonal bounded domains. For ensuring convergence, the number of iterations on each grid level has to increase from finer to coarser grids. The optimal dependence of these numbers is established with respect to the mesh size and the number of unknowns. The theory has been presented in an abstract setting which allows the application to both finite element and finite difference methods. CopyrightВ©1996 Elsevier Science Ltd. All rights reserved.
Scopus
Держатели документа:
Computing Center, Russian Academy of Sciences, Akademgorodok, Krasnoyarsk, 660036, Russian Federation
ИВМ СО РАН
Доп.точки доступа:
Shaidurov, V.V.; Шайдуров, Владимир Викторович
Evaluation of seismic hazard using seismic microzonation techniques
/ E. Bodyakin, S. Peretokin, K. Simonov // CEUR Workshop Proceedings : CEUR-WS, 2017. - Vol. 1839: 2016 International Conference Mathematical and Information Technologies, MIT 2016 (28 August 2016 through 5 September 2016, ) Conference code: 127940. - P16-25
. -
Кл.слова (ненормированные):
Earthquake -- GIS -- Seismic intensity -- Seismic microzoning -- Acoustic impedance -- Data visualization -- Density (specific gravity) -- Earthquakes -- Geographic information systems -- Geology -- Geophysics -- Hazards -- Interpolation -- Seismic response -- Shear flow -- Shear stress -- Shear waves -- Three dimensional computer graphics -- Wave propagation -- Geological environment -- P- and S-wave velocities -- Physical and mechanical properties -- Seismic hazard assessment -- Seismic intensity -- Seismic microzonation -- Seismic microzoning -- Topographic information -- Seismology
Аннотация: It was shown the technique of seismic hazard assessment based on comprehensive use of methods of seismic microzonation. This technique consists of four steps. The first step is to collect geological, seismological, geophysical and topographic information. Each layer according to geological engineering survey and geophysical work are assigned physical and mechanical properties (density, limit shear stress) and the P-And S- wave velocity. Next (step 2) after visualization and examination input data using GIS technologies 3D modelling of the geological environment is performed (it is created a grid each point of which is referred to coordinates of the site). The number and depth of soil are set in each point based on geological drilling data. Then (step 3) at each point seismic intensity are calculated using instrumental methods including the method of acoustic impedance and computer simulation (GRUNT program). At the last stage according to the analysis of the results of theoretical and instrumental methods seismic microzonation map are created using GIS technologies. The procedure of constructing maps uses different methods of selection areas with the same seismic hazard (kriging, spline interpolation).
Scopus
Держатели документа:
Institute of Computational Modeling of Siberian Branch of Russian Academy of Sciences, ICM SB RAS, Akademgorodok, Krasnoyarsk, Russian Federation
Krasnoyarsk Branch Office of Institute of Computational Technologies of Siberian Branch of Russian Academy of Sciences, Special Designing and Technological Bureau Nauka, Mira avenue 53, Krasnoyarsk, Russian Federation
Доп.точки доступа:
Bodyakin, E.; Peretokin, S.; Simonov, K.
Кл.слова (ненормированные):
Earthquake -- GIS -- Seismic intensity -- Seismic microzoning -- Acoustic impedance -- Data visualization -- Density (specific gravity) -- Earthquakes -- Geographic information systems -- Geology -- Geophysics -- Hazards -- Interpolation -- Seismic response -- Shear flow -- Shear stress -- Shear waves -- Three dimensional computer graphics -- Wave propagation -- Geological environment -- P- and S-wave velocities -- Physical and mechanical properties -- Seismic hazard assessment -- Seismic intensity -- Seismic microzonation -- Seismic microzoning -- Topographic information -- Seismology
Аннотация: It was shown the technique of seismic hazard assessment based on comprehensive use of methods of seismic microzonation. This technique consists of four steps. The first step is to collect geological, seismological, geophysical and topographic information. Each layer according to geological engineering survey and geophysical work are assigned physical and mechanical properties (density, limit shear stress) and the P-And S- wave velocity. Next (step 2) after visualization and examination input data using GIS technologies 3D modelling of the geological environment is performed (it is created a grid each point of which is referred to coordinates of the site). The number and depth of soil are set in each point based on geological drilling data. Then (step 3) at each point seismic intensity are calculated using instrumental methods including the method of acoustic impedance and computer simulation (GRUNT program). At the last stage according to the analysis of the results of theoretical and instrumental methods seismic microzonation map are created using GIS technologies. The procedure of constructing maps uses different methods of selection areas with the same seismic hazard (kriging, spline interpolation).
Scopus
Держатели документа:
Institute of Computational Modeling of Siberian Branch of Russian Academy of Sciences, ICM SB RAS, Akademgorodok, Krasnoyarsk, Russian Federation
Krasnoyarsk Branch Office of Institute of Computational Technologies of Siberian Branch of Russian Academy of Sciences, Special Designing and Technological Bureau Nauka, Mira avenue 53, Krasnoyarsk, Russian Federation
Доп.точки доступа:
Bodyakin, E.; Peretokin, S.; Simonov, K.
519.6
П 11
П 11
Пoлиномиальная интерполяция траектории Искусственного спутника земли
[Текст] : статья / Е. Д. Карепова, В. С. Корниенко // Решетневские чтения. - 2017. - № 21-2. - С. 191-192
. - ISSN 1990-7702
Перевод заглавия: Polynomial interpolation of the trajectory of an artificial earth satellite
Кл.слова (ненормированные):
интерполяция -- полином Эрмита -- полином Лагранжа -- interpolation -- the Hermite polynomial -- the Lagrange polynomial
Аннотация: Работа посвящена сравнению различных алгоритмов интерполяции траектории и скорости искусственного спутника Земли с требуемой точностью.
In this paper, we compares various algorithms of interpolation of the trajectory and speed of an artificial earth satellite with the required accuracy.
РИНЦ
Держатели документа:
Институт вычислительного моделирования СО РАН
Сибирский федеральный университет
Доп.точки доступа:
Карепова, Е.Д.; Karepova E.D.; Корниенко, В.С.; Kornienko V.S.
Перевод заглавия: Polynomial interpolation of the trajectory of an artificial earth satellite
| УДК |
Кл.слова (ненормированные):
интерполяция -- полином Эрмита -- полином Лагранжа -- interpolation -- the Hermite polynomial -- the Lagrange polynomial
Аннотация: Работа посвящена сравнению различных алгоритмов интерполяции траектории и скорости искусственного спутника Земли с требуемой точностью.
In this paper, we compares various algorithms of interpolation of the trajectory and speed of an artificial earth satellite with the required accuracy.
РИНЦ
Держатели документа:
Институт вычислительного моделирования СО РАН
Сибирский федеральный университет
Доп.точки доступа:
Карепова, Е.Д.; Karepova E.D.; Корниенко, В.С.; Kornienko V.S.
Grid of upper atmosphere models for 1-40 M-circle plus planets: application to CoRoT-7 b and HD219134 b,c
/ D. Kubyshkina [et al.] // Astron. Astrophys. - 2018. - Vol. 619. - Ст. A151, DOI 10.1051/0004-6361/201833737. - Cited References:101. - We acknowledge the Austrian Forschungsforderungsgesellschaft FFG project "TAPAS4CHEOPS" P853993, the Austrian Science Fund (FWF) NFN project S11607-N16, the FWF project P27256-N27 and the FWF project P30949-N36. N.V.E. acknowledges support by the RFBR grant No. 18-05-00195-a and 16-52-14006 ANF_a. We thank the anonymous referee for the positive approach and the useful comments that led to a significant improvement of the manuscript.
. - ISSN 1432-0746
РУБ Astronomy & Astrophysics
Аннотация: There is growing observational and theoretical evidence suggesting that atmospheric escape is a key driver of planetary evolution. Commonly, planetary evolution models employ simple analytic formulae (e.g. energy limited escape) that are often inaccurate, and more detailed physical models of atmospheric loss usually only give snapshots of an atmosphere's structure and are difficult to use for evolutionary studies. To overcome this problem, we have upgraded and employed an existing upper atmosphere hydrodynamic code to produce a large grid of about 7000 models covering planets with masses 1-39 M-circle plus with hydrogen-dominated atmospheres and orbiting late-type stars. The modelled planets have equilibrium temperatures ranging between 300 and 2000 K. For each considered stellar mass, we account for three different values of the high-energy stellar flux (i.e. low, moderate, and high activity). For each computed model, we derived the atmospheric temperature, number density, bulk velocity, X-ray and EUV (XUV) volume heating rates, and abundance of the considered species as a function of distance from the planetary centre. From these quantities, we estimate the positions of the maximum dissociation and ionisation, the mass-loss rate, and the effective radius of the XUV absorption. We show that our results are in good agreement with previously published studies employing similar codes. We further present an interpolation routine capable to extract the modelling output parameters for any planet lying within the grid boundaries. We used the grid to identify the connection between the system parameters and the resulting atmospheric properties. We finally applied the grid and the interpolation routine to estimate atmospheric evolutionary tracks for the close-in, high-density planets CoRoT-7 b and HD219134 b,c. Assuming that the planets ever accreted primary, hydrogen-dominated atmospheres, we find that the three planets must have lost them within a few Myr.
WOS,
Смотреть статью,
Scopus
Держатели документа:
Austrian Acad Sci, Space Res Inst, Schmiedlstr 6, A-8042 Graz, Austria.
Russian Acad Sci, Siberian Branch, Inst Computat Modelling, Krasnoyarsk 660036, Russia.
Siberian Fed Univ, Krasnoyarsk 660041, Russia.
Univ Vienna, Inst Astron, Turkenschanzstr 17, A-1180 Vienna, Austria.
Univ Graz Univ, IGAM, Inst Phys, Univ Pl 5, A-8010 Graz, Austria.
Доп.точки доступа:
Kubyshkina, D.; Fossati, L.; Erkaev, N. V.; Johnstone, C. P.; Cubillos, P. E.; Kislyakova, K. G.; Lammer, H.; Lendl, M.; Odert, P.; Austrian Forschungsforderungsgesellschaft FFG project "TAPAS4CHEOPS" [P853993]; Austrian Science Fund (FWF) NFN project [S11607-N16]; FWF [P30949-N36, P27256-N27]; RFBR [18-05-00195-a, 16-52-14006 ANF_a]
Рубрики:
ACTIVITY-ROTATION RELATIONSHIP
WEBB-SPACE-TELESCOPE
HOT JUPITERS
Кл.слова (ненормированные):
hydrodynamics -- planets and satellites: atmospheres -- planets and -- satellites: dynamical evolution and stability -- planets and satellites: -- individual: CoRot-7 b -- planets and satellites: individual: HD219134 b -- planets and satellites: individual: HD219134 c
ACTIVITY-ROTATION RELATIONSHIP
WEBB-SPACE-TELESCOPE
HOT JUPITERS
Кл.слова (ненормированные):
hydrodynamics -- planets and satellites: atmospheres -- planets and -- satellites: dynamical evolution and stability -- planets and satellites: -- individual: CoRot-7 b -- planets and satellites: individual: HD219134 b -- planets and satellites: individual: HD219134 c
Аннотация: There is growing observational and theoretical evidence suggesting that atmospheric escape is a key driver of planetary evolution. Commonly, planetary evolution models employ simple analytic formulae (e.g. energy limited escape) that are often inaccurate, and more detailed physical models of atmospheric loss usually only give snapshots of an atmosphere's structure and are difficult to use for evolutionary studies. To overcome this problem, we have upgraded and employed an existing upper atmosphere hydrodynamic code to produce a large grid of about 7000 models covering planets with masses 1-39 M-circle plus with hydrogen-dominated atmospheres and orbiting late-type stars. The modelled planets have equilibrium temperatures ranging between 300 and 2000 K. For each considered stellar mass, we account for three different values of the high-energy stellar flux (i.e. low, moderate, and high activity). For each computed model, we derived the atmospheric temperature, number density, bulk velocity, X-ray and EUV (XUV) volume heating rates, and abundance of the considered species as a function of distance from the planetary centre. From these quantities, we estimate the positions of the maximum dissociation and ionisation, the mass-loss rate, and the effective radius of the XUV absorption. We show that our results are in good agreement with previously published studies employing similar codes. We further present an interpolation routine capable to extract the modelling output parameters for any planet lying within the grid boundaries. We used the grid to identify the connection between the system parameters and the resulting atmospheric properties. We finally applied the grid and the interpolation routine to estimate atmospheric evolutionary tracks for the close-in, high-density planets CoRoT-7 b and HD219134 b,c. Assuming that the planets ever accreted primary, hydrogen-dominated atmospheres, we find that the three planets must have lost them within a few Myr.
WOS,
Смотреть статью,
Scopus
Держатели документа:
Austrian Acad Sci, Space Res Inst, Schmiedlstr 6, A-8042 Graz, Austria.
Russian Acad Sci, Siberian Branch, Inst Computat Modelling, Krasnoyarsk 660036, Russia.
Siberian Fed Univ, Krasnoyarsk 660041, Russia.
Univ Vienna, Inst Astron, Turkenschanzstr 17, A-1180 Vienna, Austria.
Univ Graz Univ, IGAM, Inst Phys, Univ Pl 5, A-8010 Graz, Austria.
Доп.точки доступа:
Kubyshkina, D.; Fossati, L.; Erkaev, N. V.; Johnstone, C. P.; Cubillos, P. E.; Kislyakova, K. G.; Lammer, H.; Lendl, M.; Odert, P.; Austrian Forschungsforderungsgesellschaft FFG project "TAPAS4CHEOPS" [P853993]; Austrian Science Fund (FWF) NFN project [S11607-N16]; FWF [P30949-N36, P27256-N27]; RFBR [18-05-00195-a, 16-52-14006 ANF_a]
Multidimensional Free Interpolation Framework for High-precision Modeling of Slant Total Electron Contents in Mid-latitude and Equatorial Regions
/ S. P. Tsarev, V. V. Denisenko, M. M. Valikhanov // J. Sib. Fed. Univ.-Math. Phys. - 2018. - Vol. 11, Is. 6. - P781-791, DOI 10.17516/1997-1397-2018-11-6-781-791. - Cited References:10. - S. P. Tsarev was supported by the grant from the Ministry of Education and Science of the Russian Federation no. 1.8591.2017/6.7.
. - ISSN 1997-1397. - ISSN 2313-6022
РУБ Mathematics
Кл.слова (ненормированные):
ionosphere -- total electron content -- GLONASS -- GPS -- interpolation -- machine -- learning
Аннотация: Standard models of ionospheric delays have errors of order 1-8 TECU (standard total electron content units). On the basis of the free interpolation framework we propose a new simple model of the slant TEC distributions approximating slant TEC distributions obtained from the three-dimensional ionospheric models NeQuick2 and IRI-2016 with RMS error < 0.05 TECU. The proposed model was tested for varios positions of receivers in mid-latitude and equatorial regions. Stability of the coefficients of the model with respect to the position of the receiver and time is substantiated.
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Смотреть статью,
РИНЦ,
Scopus
Держатели документа:
Siberian Fed Univ, Inst Space & Informat Technol, Svobodny 79, Krasnoyarsk 660041, Russia.
Inst Computat Modeling SB RAS, Academgorodok 50, Krasnoyarsk 660036, Russia.
Siberian Fed Univ, Inst Math & Comp Sci, Svobodny 79, Krasnoyarsk 660041, Russia.
Siberian Fed Univ, Inst Engn Phys & Radioelect, Svobodny 79, Krasnoyarsk 660041, Russia.
Доп.точки доступа:
Tsarev, Sergey P.; Denisenko, Valery V.; Valikhanov, Marat M.; Ministry of Education and Science of the Russian Federation [1.8591.2017/6.7]
Кл.слова (ненормированные):
ionosphere -- total electron content -- GLONASS -- GPS -- interpolation -- machine -- learning
Аннотация: Standard models of ionospheric delays have errors of order 1-8 TECU (standard total electron content units). On the basis of the free interpolation framework we propose a new simple model of the slant TEC distributions approximating slant TEC distributions obtained from the three-dimensional ionospheric models NeQuick2 and IRI-2016 with RMS error < 0.05 TECU. The proposed model was tested for varios positions of receivers in mid-latitude and equatorial regions. Stability of the coefficients of the model with respect to the position of the receiver and time is substantiated.
WOS,
Смотреть статью,
РИНЦ,
Scopus
Держатели документа:
Siberian Fed Univ, Inst Space & Informat Technol, Svobodny 79, Krasnoyarsk 660041, Russia.
Inst Computat Modeling SB RAS, Academgorodok 50, Krasnoyarsk 660036, Russia.
Siberian Fed Univ, Inst Math & Comp Sci, Svobodny 79, Krasnoyarsk 660041, Russia.
Siberian Fed Univ, Inst Engn Phys & Radioelect, Svobodny 79, Krasnoyarsk 660041, Russia.
Доп.точки доступа:
Tsarev, Sergey P.; Denisenko, Valery V.; Valikhanov, Marat M.; Ministry of Education and Science of the Russian Federation [1.8591.2017/6.7]
551.468.4
A10
A10
A method for reconstructing bottom topography for an enclosed basin from scattered, sparse measurement data
[Text] : статья / A. F. Shchepetkin, O. S. Volodko // Океанологические исследования. - 2018. - Т. 46, № 3. - P67-84, DOI 10.29006/1564-2291.JOR-2018.46(3).5
. - ISSN 1564-2291
Перевод заглавия: Метод построения рельефа дна для закрытого водоема из произвольно распределенных точечных данных измерений
Кл.слова (ненормированные):
reconstruction of gridded field from scattered data -- Biharmonic spline interpolation -- data quality control -- regional oceanic modeling system -- построение сеточной функции из разбросанных данных -- бигармоническая сплайн интерполяция -- выявление и отбраковка недостоверных и ненадежных данных -- региональное моделирование океана
Аннотация: Numerical simulation of circulation and internal waves in a basin requires the knowledge of bottom topography, defined as a continuous and continuously differentiable field (un-less there are known features of the relief to justify the opposite), which is, unfortunately, not always available with sufficient resolution and coverage. In this article we review ex-isting techniques for producing regularly gridded field from scattered bathymetry data - in our case raw field data measured by a boat equipped with an echo sounder and GPS - and propose a new one, which we believe is the most optimal for this situation. The technique essentially goes along the line of approach of Sandwell (1987) using Green functions to construct biharmonic spline interpolation, which we augment by adding coastline and in-troduce special preprocessing of measured data to identify and eliminate (by averaging out) potentially contradictory and unreliable measurements which may cause spurious oscillations of biharmonic spline.
Чтобы моделировать течения и внутренние волны в водоеме необходимо задать его рельеф дна в виде непрерывной, желательно непрерывно дифференцируемой функции (если, конечно, не существует физических особенностей определяющих обратное). К сожалению, данные рельефа с достаточным пространственным разрешением существуют далеко не всегда. В этой статье мы рассмотрим ранее известные методы построения полей на регулярных сетках из пространственно-разбросанных данных - в нашем случае это топография дна, измеренная эхолотом с катера, оборудованного GPS - и представим метод, который мы считаем оптимальным для нашей ситуации. Наш подход в целом следует методике работы (Sandwell, 1987), который предложил использовать бигармонические сплайны, выраженные через функции Грина для интерполяции данных спутниковых измерений геофизических полей. В нашем методе мы дополнили измеренные топографические данные береговой линией, после чего подвергли получившийся массив специальной обработке, чтобы выявить и исключить противоречивые и/или ненадежные данные, так чтобы впоследствии предотвратить нежелательные численные эффекты (осцилляции) бигармонических сплайнов.
РИНЦ
Держатели документа:
Institute of Computational Modeling SB RAS
Moscow Institute of Physics and Technology
Shirshov Institute of Oceanology, Russian Academy of Sciences
Siberian Federal University
Доп.точки доступа:
Shchepetkin, A.F.; Щепеткин А.Ф.; Volodko, O.S.; Володько О.С.
Перевод заглавия: Метод построения рельефа дна для закрытого водоема из произвольно распределенных точечных данных измерений
| УДК |
Кл.слова (ненормированные):
reconstruction of gridded field from scattered data -- Biharmonic spline interpolation -- data quality control -- regional oceanic modeling system -- построение сеточной функции из разбросанных данных -- бигармоническая сплайн интерполяция -- выявление и отбраковка недостоверных и ненадежных данных -- региональное моделирование океана
Аннотация: Numerical simulation of circulation and internal waves in a basin requires the knowledge of bottom topography, defined as a continuous and continuously differentiable field (un-less there are known features of the relief to justify the opposite), which is, unfortunately, not always available with sufficient resolution and coverage. In this article we review ex-isting techniques for producing regularly gridded field from scattered bathymetry data - in our case raw field data measured by a boat equipped with an echo sounder and GPS - and propose a new one, which we believe is the most optimal for this situation. The technique essentially goes along the line of approach of Sandwell (1987) using Green functions to construct biharmonic spline interpolation, which we augment by adding coastline and in-troduce special preprocessing of measured data to identify and eliminate (by averaging out) potentially contradictory and unreliable measurements which may cause spurious oscillations of biharmonic spline.
Чтобы моделировать течения и внутренние волны в водоеме необходимо задать его рельеф дна в виде непрерывной, желательно непрерывно дифференцируемой функции (если, конечно, не существует физических особенностей определяющих обратное). К сожалению, данные рельефа с достаточным пространственным разрешением существуют далеко не всегда. В этой статье мы рассмотрим ранее известные методы построения полей на регулярных сетках из пространственно-разбросанных данных - в нашем случае это топография дна, измеренная эхолотом с катера, оборудованного GPS - и представим метод, который мы считаем оптимальным для нашей ситуации. Наш подход в целом следует методике работы (Sandwell, 1987), который предложил использовать бигармонические сплайны, выраженные через функции Грина для интерполяции данных спутниковых измерений геофизических полей. В нашем методе мы дополнили измеренные топографические данные береговой линией, после чего подвергли получившийся массив специальной обработке, чтобы выявить и исключить противоречивые и/или ненадежные данные, так чтобы впоследствии предотвратить нежелательные численные эффекты (осцилляции) бигармонических сплайнов.
РИНЦ
Держатели документа:
Institute of Computational Modeling SB RAS
Moscow Institute of Physics and Technology
Shirshov Institute of Oceanology, Russian Academy of Sciences
Siberian Federal University
Доп.точки доступа:
Shchepetkin, A.F.; Щепеткин А.Ф.; Volodko, O.S.; Володько О.С.
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Высокоточная модель ионосферной задержки сигналов ГНСС на основе многомерной свободной интерполяции
[Текст] : статья / М. М. Валиханов, В. В. Денисенко, С. П. Царев // Успехи современной радиоэлектроники. - 2018. - № 12. - С. 90-94, DOI 10.18127/j20700784-201812-18
. - ISSN 2070-0784
Перевод заглавия: Precise modeling of slant total electron contents with multidimensional free interpolation
Кл.слова (ненормированные):
ионосферные модели -- полное электронное содержание -- продукты IGS -- глонасс -- gps -- интерполяция -- машинное обучение -- Ionosphere modeling -- total electron content -- IGS Products -- GLOnASS -- interpolation -- machine learning
Аннотация: Предложена новая интерполяционная модель ионосферных задержек, способная обеспечить точность определения наклонных ПЭС 0,02 TECU относительно соответствующих наклонных ПЭС, вычисленных с помощью современных трехмерных моделей ионосферы.
Standard models of ionospheric delays widely used for practical processing of navigation signals from global navigation satellite systems (GNSS) usually approximate the complicated three-dimensional electron density distribution in the Earth's ionosphere and plasmasphere with one- or two-layer distributions and have errors of order 1-8 TECU (total electron content units). Publicly available modern three-dimensional ionospheric models IRI-2016 and NeQuick2 are very complex, they are not easy to use in GNSS applications and have similar large deviations from real ionospheric data. We propose a new interpolation model of ionospheric delays which is much more precise than the one- or two-layer models but simple enough to be used in radiophysics and GNSS applications. It is based on our recent free interpolation framework used previously in finding positions of GNSS satellites from SP3 data with very high precision. The free interpolation framework is not limited to polynomial, trigonometric or spherical interpolating functions and uses a simple machine learning approach for definition of the interpolation coefficients. Our model approximates the slant TEC angular distributions obtained from modern three-dimensional ionospheric models with RMS error 0,02 TECU. The new model of ionospheric delays is universal, stable and have weak dependence on the position of the GNSS ground receiver. Experimental verification of our model was performed for two IGS stations: АМС4 (B=38,80312°, L= -104,524594°, H=1912,5 м) and PIE1 (B=34,301505°, L= -108,118927°, H = 2347,7 м) for STEC distributions calculated using both ionospheric models IRI-2016 and NeQuick2 for the years 2008 and 2017. We show that interpolation coefficients may be chosen equal for both stations and both years. Investigating deeper one may observe a small seasonal variations of the residuals of our model: RMS = 0,03 TECU for winter months and RMS = 0,05 TECU for summer months for the smallest number of parameters in our model N=7. For N=10 parameters one obtains RMS < 0,02 TECU. Further research is planned to test the free interpolation ionospheric STEC model on real measurements from GNSS stations. Integration of our model and methods for differential code biases (DCBs in satellite transmitters and ground receivers) separation is obviously necessary for this test. Possible inclusion of higher order ionospheric effects is under study.
РИНЦ
Держатели документа:
Институт вычислительного моделирования СО РАН
ФГАОУ ВО «Сибирский федеральный университет»
Доп.точки доступа:
Валиханов, М.М.; Valikhanov M.M.; Денисенко, В.В.; Denisenko V.V.; Царев, С.П.; Tsarev S.P.
Перевод заглавия: Precise modeling of slant total electron contents with multidimensional free interpolation
| УДК |
Кл.слова (ненормированные):
ионосферные модели -- полное электронное содержание -- продукты IGS -- глонасс -- gps -- интерполяция -- машинное обучение -- Ionosphere modeling -- total electron content -- IGS Products -- GLOnASS -- interpolation -- machine learning
Аннотация: Предложена новая интерполяционная модель ионосферных задержек, способная обеспечить точность определения наклонных ПЭС 0,02 TECU относительно соответствующих наклонных ПЭС, вычисленных с помощью современных трехмерных моделей ионосферы.
Standard models of ionospheric delays widely used for practical processing of navigation signals from global navigation satellite systems (GNSS) usually approximate the complicated three-dimensional electron density distribution in the Earth's ionosphere and plasmasphere with one- or two-layer distributions and have errors of order 1-8 TECU (total electron content units). Publicly available modern three-dimensional ionospheric models IRI-2016 and NeQuick2 are very complex, they are not easy to use in GNSS applications and have similar large deviations from real ionospheric data. We propose a new interpolation model of ionospheric delays which is much more precise than the one- or two-layer models but simple enough to be used in radiophysics and GNSS applications. It is based on our recent free interpolation framework used previously in finding positions of GNSS satellites from SP3 data with very high precision. The free interpolation framework is not limited to polynomial, trigonometric or spherical interpolating functions and uses a simple machine learning approach for definition of the interpolation coefficients. Our model approximates the slant TEC angular distributions obtained from modern three-dimensional ionospheric models with RMS error 0,02 TECU. The new model of ionospheric delays is universal, stable and have weak dependence on the position of the GNSS ground receiver. Experimental verification of our model was performed for two IGS stations: АМС4 (B=38,80312°, L= -104,524594°, H=1912,5 м) and PIE1 (B=34,301505°, L= -108,118927°, H = 2347,7 м) for STEC distributions calculated using both ionospheric models IRI-2016 and NeQuick2 for the years 2008 and 2017. We show that interpolation coefficients may be chosen equal for both stations and both years. Investigating deeper one may observe a small seasonal variations of the residuals of our model: RMS = 0,03 TECU for winter months and RMS = 0,05 TECU for summer months for the smallest number of parameters in our model N=7. For N=10 parameters one obtains RMS < 0,02 TECU. Further research is planned to test the free interpolation ionospheric STEC model on real measurements from GNSS stations. Integration of our model and methods for differential code biases (DCBs in satellite transmitters and ground receivers) separation is obviously necessary for this test. Possible inclusion of higher order ionospheric effects is under study.
РИНЦ
Держатели документа:
Институт вычислительного моделирования СО РАН
ФГАОУ ВО «Сибирский федеральный университет»
Доп.точки доступа:
Валиханов, М.М.; Valikhanov M.M.; Денисенко, В.В.; Denisenko V.V.; Царев, С.П.; Tsarev S.P.
The comparison of several approaches to the interpolation of a trajectory of a navigation satellite
/ E. D. Karepova, V. S. Kornienko // IOP Conference Series: Materials Science and Engineering : Institute of Physics Publishing, 2019. - Vol. 537: International Workshop on Advanced Technologies in Material Science, Mechanical and Automation Engineering - MIP: Engineering-2019 (4 April 2019 through 6 April 2019, ) Conference code: 149243, Is. 2. - Ст. 022054, DOI 10.1088/1757-899X/537/2/022054
. -
Кл.слова (ненормированные):
Interpolation -- Satellites -- Navigation satellites -- Polynomial interpolation -- Real-time application -- Satellite orbit -- Satellite position -- Orbits
Аннотация: Since a satellite orbit is quite smooth, polynomial techniques can be widely used for the interpolation of satellite positions in real-time applications. The paper is devoted to the comparison of different approaches to the polynomial interpolation of the trajectory of a satellite using available data. All approaches have been examined for test and actual data. © 2019 Published under licence by IOP Publishing Ltd.
Scopus,
Смотреть статью
Держатели документа:
Institute of Computational Modeling, Siberian Branch of Russian Academy of Sciences, 50/44 Akademgorodok, Krasnoyarsk, 660036, Russian Federation
Siberian Federal University, 79 Svobodnyi Prospect, Krasnoyarsk, 660041, Russian Federation
Доп.точки доступа:
Karepova, E. D.; Kornienko, V. S.
Кл.слова (ненормированные):
Interpolation -- Satellites -- Navigation satellites -- Polynomial interpolation -- Real-time application -- Satellite orbit -- Satellite position -- Orbits
Аннотация: Since a satellite orbit is quite smooth, polynomial techniques can be widely used for the interpolation of satellite positions in real-time applications. The paper is devoted to the comparison of different approaches to the polynomial interpolation of the trajectory of a satellite using available data. All approaches have been examined for test and actual data. © 2019 Published under licence by IOP Publishing Ltd.
Scopus,
Смотреть статью
Держатели документа:
Institute of Computational Modeling, Siberian Branch of Russian Academy of Sciences, 50/44 Akademgorodok, Krasnoyarsk, 660036, Russian Federation
Siberian Federal University, 79 Svobodnyi Prospect, Krasnoyarsk, 660041, Russian Federation
Доп.точки доступа:
Karepova, E. D.; Kornienko, V. S.