The Onset of Synchronization in Systems of Globally Coupled Chaotic and   Periodic Oscillators
  A general stability analysis is presented for the determination of the transition from incoherent to coherent behavior in an ensemble of globally coupled, heterogeneous, continuous-time dynamical systems. The formalism allows for the simultaneous presence of ensemble members exhibiting chaotic and periodic behavior, and, in a special case, yields the Kuramoto model for globally coupled periodic oscillators described by a phase. Numerical experiments using different types of ensembles of Lorenz equations with a distribution of parameters are presented. 
Edward Ott, Paul So, Ernest Barreto and Thomas Antonsen