  The calculation of optimal structures in reaction-diffusion models is of
great importance in many physicochemical systems. We propose here a simple
method to monitor the number of interphases for long times by using a boundary
flux condition as a control. We consider as an illustration a 1-D Allen-Cahn
equation with Neumann boundary conditions. Numerical examples are given and
perspectives for the application of this approach to electrochemical systems
are discussed.
