Synchronization stability of continuous/discrete complex dynamical networks with interval time-varying delays

The synchronization problem of continuous/discrete general complex dynamical networks with time-varying delays is investigated. The delays considered in this paper are assumed to vary in an interval, where the lower and upper bounds are known. Based on a piecewise analysis method, the variation interval of the time delay is firstly divided into several subintervals, by checking the variation of derivative of a Lyapunov functional in every subinterval, then the convexity of matrix function method and the free-weighting matrix method are fully used in this paper. Some new delay-dependent synchronization stability criteria are derived in the form of linear matrix inequalities. Several numerical examples show that our method can lead to much less conservative results than those in the existing references.