Feedback solution of a control problem for a parabolic operator of order 2m (Q803918)

Some optimal control problems with quadratic cost functional for parabolic operators were studied by \textit{M. Giurgiu} [Rev. Roum. Math. Pures Appl. 20, 927-954 (1975; Zbl 0326.49014)]. Following these ideas I studied previously [Rend. Accad. Sci. Fis. Mat., Napoli, IV. Ser. 52(1985), No.2, 29-39 (1987; Zbl 0726.49002)] an optimal control problem for a parabolic operator of order 2m, where I stated some results about existence, uniqueness and regularity. The same problem under more general conditions is considered here again and a differential characterization of the form of the feedback for the optimal control is achieved.