... convergence rates of the sequencexhαtoudepend on thechoice ofα = α(h). In [6], one has showed that the parameterαcan be chosen by themodified generalized discrepancy principle, i.e.,α ... discrepancyprinciple for the choice˜α = α(h, n)so thatxh˜α,nconverges tou, ash, α → 0andn → ∞.Note that, the generalized discrepancy principle for parameter choice is presented first ... Tˆo´cdˆo.hˆo.i tu.cu’a nghiˆe.m hiˆe.u chı’nh nhˆa.n du.o..c du..a trˆen viˆe.c cho .n tham sˆo´hiˆe.uchı’nh tru.´o.c ho˘a.c sau b˘a`ng nguyˆen l´ydˆo.lˆe.ch...