Reduction of a distributed system to a lumped system via state feedback

For a class of single input-output linear dynamical systems with time lags, there exist input and state feedback control laws containing delay lines such that the closed-loop systems are zero-state equivalent to systems which are specified by ordinary differential equations without time lags. A necessary and sufficient condition for the existence of these control laws and a constructive procedure for finding these control laws are given. Furthermore, the set of poles of the closed loop system transfer function can be arbitrarily assigned by choosing the feedback laws appropriately.