Dissipative structures in an active diffusive medium with a spatially periodic source

The problem of quasi-harmonic dissipative structures (stratifications) in a distributed active diffusive medium is analyzed in the case in which the medium contains a spatially periodic source of particles, heat, etc., and the period of this source is not the period of the spontaneous stratification which results from the Turing instability. Self-excited oscillatory structures can exist with parameters which vary in time, as can structures with a smooth spatial modulation of parameters. Switching can occur between static and oscillatory stratifications.