Not available

Não disponívelOn this work we study stability properties of a system of Difference Equations x(t) = ∑Nk=1 Ak x(t-rk ), x ∈ Rn, Ak, n x n constant matrices, rk > 0, in the case that we allow the delays rk to vary in time. The main result we obtained is that if the above system is stable and the matrices Ak satisfy a commutative condiction Ak A*j = A*j, j, k = 1, 2, ..., n, then the system x(t) = ∑Nk=1 Ak x(t-rk (t)) is also stable