  We summarize and extend some of the results obtained recently for the
microscopic and macroscopic behavior of a pinned harmonic chain, with random
velocity flips at Poissonian times, acted on by a periodic force {at one end}
and in contact with a heat bath at the other end. Here we consider the case
where the system is in contact with two heat baths at different temperatures
and a periodic force is applied at any position. This leads in the hydrodynamic
limit to a heat equation for the temperature profile with a discontinuous slope
at the position where the force acts. Higher dimensional systems, unpinned
cases and anharmonic interactions are also considered.
