NEUMANN CONTROL OF UNSTABLE PARABOLIC-SYSTEMS - NUMERICAL APPROACH

The present article is concerned with the Neumann control of systems m odeled by scalar or vector parabolic equations of reaction-advection-d iffusion type with a particular emphasis on systems which are unstable if uncontrolled. To solve these problems, we use a combination of fin ite-difference methods for the time discretization, finite-element met hods for the space discretization, and conjugate gradient algorithms f or the iterative solution of the discrete control problems. We apply t hen the above methodology to the solution of test problems in two dime nsions, including problems related to nonlinear models.