Stability of Positive Differential Systems With Delay

We first prove an explicit criterion for positive linear time-varying differential systems with distributed delay. Then some simple criteria for exponential stability of positive linear time-invariant differential systems with delay are presented. Finally, we extend obtained results to linear differential systems with time-varying delay and to nonlinear differential systems with delay. The results given in this technical note are extensions of some recent results in ,[7],[11] and [14].