On Stability of A Class of Stochastic Neutral -Type Time -Delay Systems

This paper studies mean square exponential bility of linear stochastic neutral type time -delay systems with multiple point delays by using an augmented Lyapunov-Krasovskii functional (LKF) approach. To build a suitable augmented LKF, a method is proposed to find an augmented state vector whose elements are linearly independent. With the help of the linearly independent augmented state vector, the constructed I,KF and properties of the stochastic integral, sufficient delay-dependent stability conditions expressed by linear matrix inequalities (LMIs) are established to guarantee the mean square exponential stability of the system. Differently from previous results where the difference operator associated with the system needs to satisfy a condition in terms of matrix norms, in the current paper the difference operator only needs to satisfy a less restrictive condition in terms of matrix spectral radius.