spatial behavior of solutions for a class of hyperbolic equations with nonlinear dissipative terms

This paper deals with the spatial behavior of solutions for a viscoelastic wave equations with nonlinear dissipative terms in a semiinfinite n-dimensional cylindrical domain. an alternative of phragm´enlindel¨of type theorems is obtained in the result. in the case of decay, an upper bound will be derived for the total energy by means of the boundary data. the main point of the contribution is the use of energy method.