摘要

The lowest order H (1)-Galerkin mixed finite element method (for short MFEM) is proposed for a class of nonlinear sine-Gordon equations with the simplest bilinear rectangular element and zero order Raviart-Thomas element. Base on the interpolation operator instead of the traditional Ritz projection operator which is an indispensable tool in the traditional FEM analysis, together with mean-value technique and high accuracy analysis, the superclose properties of order O(h (2))/O(h (2) + tau (2)) in H (1)-norm and H(div;Omega)-norm are deduced for the semi-discrete and the fully-discrete schemes, where h, tau denote the mesh size and the time step, respectively, which improve the results in the previous literature.

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