Fatemah Ateeq-Allah El-shatery2022-05-192022-05-191110https://drepo.sdl.edu.sa/handle/20.500.14154/10548In this thesis, we present some results in the area of the minimization problems of some functionals and boundary value problems with application in the area of optimal control theory concerning elliptic and parabolic partial differential systems with boundary Neumann conditions involving self-adjoint second order operators with infinite number of variables.enThesis