“…With ℓ " 1, 2, ¨¨¨, k, we denote by p ℓ ą 1, the power exponents of nonlinear terms, moreover, the dissipative terms B t u ℓ and p´∆q σ B t u ℓ stand for the frictional dissipation (or external damping) and visco-elastic dissipation (or strong damping), respectively. The corresponding linear equation of (1) we have in mind is # u tt `p´∆q σ u `ut `p´∆q σ u t " 0, x P R n , t ě 0 up0, xq " u 0 pxq, u t p0, xq " u 1 pxq,…”