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On conditions for L2-dissipativity of linearized explicit QGD finite-difference schemes for one-dimensional gas dynamics equations
Doklady Mathematics. 2018. Vol. 98. No. 2. P. 458-463.
An explicit two-time-level and spatially symmetric finite-difference scheme approximating the 1D quasi-gasdynamic system of equations is studied. The scheme is linearized about a constant solution, and new necessary and sufficient conditions for the L2 -dissipativity of solutions of the Cauchy problem are derived, including, for the first time, the case of a nonzero background velocity depending on the Mach number. It is shown that the condition on the Courant number can be made independent of the Mach number. The results provide a substantial development of the well-known stability analysis of the linearized Lax–Wendroff scheme.
Language:
English
Zlotnik A., Lomonosov T., Доклады Академии наук 2018 Т. 482 № 4 С. 375-380
Изучается явная двухслойная по времени и симметричная по пространству разностная схема, аппроксимирующая 1D квазигазодинамическую систему уравнений. Она линеаризуется на постоянном решении и для нее выводятся новые как необходимые, так и достаточные условия $L^2$-диссипативности решений задачи Коши, в том числе впервые при ненулевой фоновой скорости в зависимости от числа Маха.
Показано, что можно обеспечить независимость условия на число ...
Added: May 21, 2018
Zlotnik A., Lomonosov T., Журнал вычислительной математики и математической физики 2019 Т. 59 № 3 С. 481-493
Изучаются явные двухслойные по времени и симметричные по пространству разностные схемы, построенные посредством аппроксимации 1D баротропных квазигазо/квазигидродинамических систем уравнений. Они линеаризуются на постоянном решении с ненулевой скоростью, и для них выводятся как необходимые, так и достаточные условия $L^2$-диссипативности решений задачи Коши в зависимости от числа Маха. Эти условия различаются между собой не более чем в 2 раза. Результаты ...
Added: September 26, 2018
Zlotnik Alexander, Zlotnik Ilya, Computational Methods in Applied Mathematics 2015 Vol. 15 No. 2 P. 233-245
We consider the Cauchy problem for the 1D generalized Schrὅdinger equation on the whole axis. To solve it, any order finite element in space and the Crank-Nicolson in time method with the discrete transpa\-rent boundary conditions (TBCs) has recently been constructed. Now we engage the global Richardson extrapolation in time to derive the high order ...
Added: March 3, 2015
Zlotnik A.A., Lomonosov T.A., Computational Mathematics and Mathematical Physics 2019 Vol. 59 No. 3 P. 452-464
Explicit two-level in time and symmetric in space finite-difference schemes constructed by approximating the 1D barotropic quasi-gas-/quasi-hydrodynamic systems of equations are studied. The schemes are linearized about a constant solution with a nonzero velocity, and, for them, necessary and sufficient conditions for the L2-dissipativity of solutions to the Cauchy problem are derived depending on the Mach number. These conditions ...
Added: March 11, 2019
А. А. Злотник, Т. А. Ломоносов, Доклады Российской академии наук. Математика, информатика, процессы управления (ранее - Доклады Академии Наук. Математика) 2020 Т. 492 № 1 С. 31-37
We study an explicit two-level symmetric in space finite-difference scheme for the multi\-di\-men\-si\-onal barotropic gas dynamics system of equations with quasi-gasdynamic regulari\-za\-tion linearized at a constant solution (with arbitrary velocity). A criterion and both necessary and sufficient conditions for the $L^2$-dissipativity of the solutions to the Cauchy problem for the scheme are derived by the spectral ...
Added: March 4, 2020
Zlotnik A. A., Chetverushkin B. N., Doklady Mathematics 2017 Vol. 95 No. 3 P. 276-281
Entropy balance in the one-dimensional hyperbolic quasi-gasdynamic (HQGD) system of equations is analyzed. In regular flow regimes, it is shown that the behavior of entropy in the HQGD system is determined by terms involving the natural viscosity and thermal conductivity coefficients. The total entropy production differs from the Navier–Stokes equations for viscous compressible heat-conducting gases ...
Added: April 25, 2017
V.A. Gavrilin, A.A. Zlotnik, Computational Mathematics and Mathematical Physics 2015 Vol. 55 No. 2 P. 264-281
The one-dimensional quasi-gasdynamic system of equations in the form of mass, momentum, and total energy conservation laws with general gas equations of state is considered. A family of three-point symmetric spatial discretizations of this system is studied for which the internal energy equation has a suitable form (without imbalance terms). An entropy balance equation is ...
Added: February 21, 2015
Zlotnik A., Lomonosov T., Mathematical Modelling and Analysis 2019 Vol. 24 No. 2 P. 179-194
An entropy dissipative spatial discretization has recently been constructed for the multidimensional gas dynamics equations based on their preliminary parabolic quasi-gasdynamic (QGD) regularization. In this paper, an explicit finite-difference scheme with such a discretization is verified on several versions of the 1D Riemann problem, both well-known in the literature and new. The scheme is compared with the ...
Added: November 28, 2018
Zlotnik A., Lomonosov T., Математическое моделирование 2021 Т. 33 № 5 С. 16-34
We study explicit two-level finite-difference schemes on staggered meshes for two known regularizations of 1D barotropic gas dynamics equations including schemes with discretizations in x that possess the dissipativity property with respect to the total energy. We derive criterions of L^2-dissipativity in the Cauchy problem for their linearizations at a constant solution with zero background ...
Added: April 1, 2021
Chetverushkin B. N., Zlotnik A.A., Russian Journal of Mathematical Physics 2017 Vol. 24 No. 3 P. 299-309
We study a multidimensional hyperbolic quasi-gasdynamic (HQGD) system of equations containing terms with a regularizing parameter $\tau>0$ and 2nd order space and time derivatives; the body force is taken into account. We transform it to the form close to the compressible Navier-Stokes system of equations. Then we derive the entropy balance equation and show that ...
Added: July 19, 2017
Malyshev D., Gribanov D., Discrete Optimization 2018 Vol. 29 P. 103-110
We consider boolean linear programming formulations of the vertex and edge dominating set problems and prove their polynomial-time solvability for classes of graphs with constraint matrices having bounded minors in the absolute value. ...
Added: April 8, 2018
Злотник А.А., Доклады Академии наук 2010 Т. 431 № 5 С. 605-609
Квазигазодинамическая (КГД) система уравнений была предложена Б.Н. Четверушкиным и Т.Г. Елизаровой и затем модифицировалась Т.Г. Елизаровой и Ю.В. Шеретовым. Она рассматривалась только с уравнениями состояния совершенного политропного газа. В работе предложено ее обобщение на случай общих уравнений состояния, связанных равенством Максвелла и удовлетворяющих условиям термодинамической устойчивости. Для КГД системы с общими уравнениями состояния выведен закон ...
Added: December 22, 2015
Vyalyi M., Дискретная математика 1991 Т. 3 № 3 С. 35-45
Added: October 17, 2014
Kuznetsov V. O., Логистика и управление цепями поставок 2018 № 4 (87) С. 27-33
One of the options for a more flexible approach to analyzing the reliability of supply chains is the principal component analysis (PCA). With a large number of variables describing supply chain, it is a difficult task to analyze the structure of variables in two-dimensional space. Within the analysis of the variables dependencies PCA allows to ...
Added: November 29, 2018
Lanham : University Press of America, 2012
The history of logic and analytic philosophy in Central and Eastern Europe is still known to very few people. As an exception to the rule, only two scientific schools became internationally popular: the Vienna Circle and the Lvov-Warsaw School. Nevertheless, the countries included in this region have not only joint history, but also joint cultural ...
Added: February 13, 2013
Malyshev D., / Cornell University. Series math "arxiv.org". 2013. No. 1307.0278v1.
The coloring problem is studied in the paper for graph classes defined by two small forbidden induced subgraphs. We prove some sufficient conditions for effective solvability of the problem in such classes. As their corollary we determine the computational complexity for all sets of two connected forbidden induced subgraphs with at most five vertices except ...
Added: October 3, 2013
Пенза : ПГУ, 2015
В сборник трудов включены доклады юбилейного ХХ-го Международного симпозиума «Надежность и качество», проходившего с 25 по 31 мая 2015 г. в городе Пензе.
Рассмотрены актуальные проблемы теории и практики повышения надежности и качества; эффективности внедрения инновационных и информационных технологий в фундаментальных научных и прикладных исследованиях, образовательных и коммуникативных системах и средах, экономике и юриспруденции; методов и ...
Added: May 31, 2015
Malyshev D., Дискретный анализ и исследование операций 2020 Т. 27 № 4 С. 104-130
Задача о рёберной раскраске для заданного графа состоит в том, чтобы минимизировать количество цветов, достаточное для окрашивания его рёбер так, чтобы соседние рёбра были окрашены в разные цвета. Для всех классов графов, определяемых запрещением подграфов с не более чем 6 рёбрами каждый, известен
сложностной статус этой задачи. В настоящей работе данный результат улучшается и получена полная ...
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Popkov Y., Popkov A., Dubnov Y. A., Автоматика и телемеханика 2020 № 7 С. 148-172
A randomized forecasting method based on the generation of ensembles of entropy-optimal forecasting trajectories is developed. The latter are generated by randomized dynamic regression models containing random parameters, measurement noises, and a random input. The probability density functions of random parameters and measurement noises are estimated using real data within the randomized machine learning procedure. ...
Added: October 31, 2020
Malyshev D., Discrete Mathematics 2015 Vol. 338 No. 11 P. 1860-1865
We completely determine the complexity status of the 3-colorability problem for hereditary graph classes defined by two forbidden induced subgraphs with at most five vertices. ...
Added: April 7, 2014
Marshirov V. V., Marshirova L. E., Сибирский журнал индустриальной математики 2013 Т. XVI № 4 С. 111-120
The paper considers the problem of determining the rate of cooling of metal during solidification at the intersection of the liquidus temperature under intense heat sink from the surface. The solution to this problem it is necessary to determine the process conditions, the boundary and initial conditions for which it is possible to get new ...
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Akopov A. S., Beklaryan L. A., Saghatelyan A. K., Environmental Modelling and Software 2019 Vol. 116 P. 7-25
Urban greenery such as trees can effectively reduce air pollution in a natural and eco-friendly way. However, how to spatially locate and arrange greenery in an optimal way remains as a challenging task. We developed an agent-based model of air pollution dynamics to support the optimal allocation and configuration of tree clusters in a city. The Pareto ...
Added: February 24, 2019
Malyshev D., Journal of Applied and Industrial Mathematics (перевод журналов "Сибирский журнал индустриальной математики" и "Дискретный анализ и исследование операций") 2020 Vol. 14 No. 4 P. 706-721
The edge coloring problem for a graph is to minimize the number of colors that are sufficient to color all edges of the graph so that all adjacent edges receive distinct colors. The computational complexity of the problem is known for all graph classes defined by forbidden subgraphs with at most 6 edges. We improve ...
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Kryuchkov M., Rusakov S. V., Вестник Ижевского государственного технического университета 2015 № 2(66) С. 110-112
This paper describes the results of testing the neuronal technical trend indicator according to the exchange rate of Brent oil in 2014. Testing of the model was carried out on three time series, which characterized by their features. ...
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