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تسجيل مستخدم جديدA Fourier Pseudospectral Method for the Good Boussinesq Equation with Second Order Temporal Accuracy
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In this paper, we discuss the nonlinear stability and convergence of a fully discrete Fourier pseudospectral method coupled with a specially designed second order time-stepping for the numerical solution of the good Boussinesq equation. Our analysis improves the existing results presented in earlier literature in two ways. First, an $l_infty(0, T^*; H2)$ convergence for the solution and $l_infty(0, T^*; l_2)$ convergence for the time-derivative of the solution are obtained in this paper, instead of the $l_infty(0, T^*; l_2)$ convergence for the solution and the $l_infty(0, T^*; H^{-2})$ convergence for the time-derivative, given in [17]. In addition, the stability and convergence of this method is shown to be unconditional for the time step in terms of the spatial grid size, compared with a severe restriction time step restriction $Delta t leq Ch^2$ reported in [17].
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