本刊英文版2021年64卷第5期(887-1108)摘要

Analysis of the second-order BDF scheme with variable steps for the molecular beam epitaxial model without slope selection Hong-Lin Liao,Xuehua Song,Tao Tang&Tao Zhou Abstract In this work,we are concerned with the stability and convergence analysis of the second-order backward difference formula(BDF2)with variable steps for the molecular beam epitaxial model without slope selection.We first show that the variable-step BDF2 scheme is convex and uniquely solvable under a weak time-step constraint.Then we show that it preserves an energy dissipation law if the adjacent time-step ratios satisfy rk:=τk/τk?1<3.561.Moreover,with a novel discrete orthogonal convolution kernels argument and some new estimates on the corresponding positive definite quadratic forms,the L² norm stability and rigorous error estimates are established,under the same step-ratio constraint that ensures the energy stability,i.e.,0相似文献   

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