“…Matrix A = diag{mθ, mλ 1 , mλ 2 , mλ 3 , mŨ , mW } collecting the coefficients for the derivative term of all the unknowns with regard to time T , in which, mŨ , mW are the identity matrixes as all the coefficients forÜ ,Ẅ are 1, while the sub-matrixes associated with mθ, mλ 1 , mλ 2 , mλ 3 are all zero as there are no derivative terms of the variables with regard to time T (see (11), also see (2)), so A is a singular matrix. H is a vector collecting all the algebraic functions resulting from spatial discretization for the associated unknowns.…”