“…Such a divergent problem could be avoided by using regularization methods [1,2,4,7,15,18,19,[21][22][23][24]. For examples, the truncated singular value decomposition technique (TSVD) [10,11,17,19], the zeroth order and first order techniques of Tikhonov regularization technique [1,2,9,12,13,19,20] have been applied to deal with divergent problems. The three techniques can obtain a convergence solution more precisely and reasonably.…”