Smoother Basic Principles Under-Relaxed Jacobi 05 1/2 R=R3+(1-)0 ①=23 -5 (UNSTABLE) =1 mode k 入(a)=u(R)+(1-a)=1-c(1-入(E)), 1=1 SMA-HPC⊙2003MT Iterative Methods: Multigrid Techniques 6