a1 Department of Mathematics, Northeast Normal University, Changchun 130024, P. R. China.
a2 Department of Mathematics, Fudan University, Shanghai 200433, P. R. China.
In this paper, we consider the system governed via the coefficients of a semilinear elliptic equation and give the necessary conditions for optimal control. Furthermore, we obtain the necessary conditions for an optimal domain in a domain optimization problem.
(Received March 29 1996)
(Revised January 27 1998)