  In this paper we consider feedback stabilization for parabolic variational
inequalities of obstacle type with time and space depending reaction and
convection coefficients and show exponential stabilization to nonstationary
trajectories. Based on a Moreau-Yosida approximation, a feedback operator is
established using a finite (and uniform in the approximation index) number of
actuators leading to exponential decay of given rate of the state variable.
Several numerical examples are presented addressing smooth and nonsmooth
obstacle functions.
