Fa. Khodja et A. Bader, Stabilizability of systems of one-dimensional wave equations by one internal or boundary control force, SIAM J CON, 39(6), 2001, pp. 1833-1851
We study the internal and boundary stabilizability of a system of wave equa
tions by one control force. We prove that the classical internal damping ap
plied to only one of the equations never gives exponential stability if the
wave speeds are different and, if the wave speeds are the same, we give ex
plicit necessary and sufficient conditions for the stability to occur. We a
lso study the simultaneous boundary stabilization of the same system.