The method of numerical solving of nonlinear model problems of theory of a complex quasi-potential in doubly-connected nonlinear-layered curvilinear domains considering inverse influence function of flow on a conducti...The method of numerical solving of nonlinear model problems of theory of a complex quasi-potential in doubly-connected nonlinear-layered curvilinear domains considering inverse influence function of flow on a conductivity coefficient of medium was developed on the basis of synthesis of numerical methods of the quasi-conformal mappings and summary representations in conjunction with domain decomposition by method Schwartz. The proposed algorithm allows finding the potential of the quasiideals field, construction a motion grid （fluid-flow grid） simultaneously defining the flow lines that separate of sub-domains constancy of coefficient conductivity and identification the piecewise-constant values of coefficient conductivity, the local flows for the known measurements on boundary of domain.展开更多
This paper proposes the least-squares Galerkin finite dement scheme to solve secona-oraer hyperbolic equations. The convergence analysis shows that the method yields the approximate solutions with optimal accuracy in ...This paper proposes the least-squares Galerkin finite dement scheme to solve secona-oraer hyperbolic equations. The convergence analysis shows that the method yields the approximate solutions with optimal accuracy in （L2 （Ω））2 × L2 （Ω） norms. Moreover, the method gets the approximate solutions with second-order accuracy in time increment. A numerical example testifies the efficiency of the novel scheme. Key words Convergence analysis, Galerkin finite element, hyperbolic equations, least-squares, nu- merical example.展开更多
In this paper, the problem of determining the most general Lie point symmetries group and conservation laws of a well known nonlinear hyperbolic PDE in mathematical physics called the Hunter-Saxton equation （HSE） is...In this paper, the problem of determining the most general Lie point symmetries group and conservation laws of a well known nonlinear hyperbolic PDE in mathematical physics called the Hunter-Saxton equation （HSE） is anaiyzed. By applying the basic Lie symmetry method for the HSE, the classical Lie point symmetry operators are obtained. Also, the algebraic structure of the Lie algebra of symmetries is discussed and an optimal system of one- dimensional subalgebras of the HSE symmetry algebra which creates the preliminary classification of group invariant solutions is constructed. Particularly, the Lie invariants as well as similarity reduced equations corresponding to in- finitesimal symmetries are obtained. Mainly, the conservation laws of the HSE are computed via three different methods including Boyer＇s generalization of Noether＇s theorem, first homotopy method and second homotopy method.展开更多
文摘The method of numerical solving of nonlinear model problems of theory of a complex quasi-potential in doubly-connected nonlinear-layered curvilinear domains considering inverse influence function of flow on a conductivity coefficient of medium was developed on the basis of synthesis of numerical methods of the quasi-conformal mappings and summary representations in conjunction with domain decomposition by method Schwartz. The proposed algorithm allows finding the potential of the quasiideals field, construction a motion grid （fluid-flow grid） simultaneously defining the flow lines that separate of sub-domains constancy of coefficient conductivity and identification the piecewise-constant values of coefficient conductivity, the local flows for the known measurements on boundary of domain.
基金This research is supported by the Mathematical Tianyuan Foundation of China under Grant No. 10726032, the National Natural Science Foundation of China under Grant No. 10471099, and the Fundamental Research Funds for the Central Universities.
文摘This paper proposes the least-squares Galerkin finite dement scheme to solve secona-oraer hyperbolic equations. The convergence analysis shows that the method yields the approximate solutions with optimal accuracy in （L2 （Ω））2 × L2 （Ω） norms. Moreover, the method gets the approximate solutions with second-order accuracy in time increment. A numerical example testifies the efficiency of the novel scheme. Key words Convergence analysis, Galerkin finite element, hyperbolic equations, least-squares, nu- merical example.
文摘In this paper, the problem of determining the most general Lie point symmetries group and conservation laws of a well known nonlinear hyperbolic PDE in mathematical physics called the Hunter-Saxton equation （HSE） is anaiyzed. By applying the basic Lie symmetry method for the HSE, the classical Lie point symmetry operators are obtained. Also, the algebraic structure of the Lie algebra of symmetries is discussed and an optimal system of one- dimensional subalgebras of the HSE symmetry algebra which creates the preliminary classification of group invariant solutions is constructed. Particularly, the Lie invariants as well as similarity reduced equations corresponding to in- finitesimal symmetries are obtained. Mainly, the conservation laws of the HSE are computed via three different methods including Boyer＇s generalization of Noether＇s theorem, first homotopy method and second homotopy method.
