Contents I. Introduction
A complex dynamical network is a collection of dynamic systems, called nodes, connected by links that exhibit complex topological properties. Complex dynamical networks have been widely exploited to model many complex systems in sciences, engineering and society, and have attracted tremendous attention in recent years (see [2], [3] and the references therein). As the major collective behavior, synchronization is one of the key issues that have been extensively addressed. A vast number of papers on the topic have appeared. Some surveys have recently appeared in [24] and [29]. This topic has been mainly explored mathematically in the physics community with some recent papers in Circuits and Systems [28], Automatic Control [15], [30] and Mathematics [23] journals. The topic is not unrelated to the study of consensus problems in swarms [12], [18], [25], [31] which can be seen as a kind of time-varying network.
