Existence and stability of positiveperiodic solution for BAM neural networks with delays

In this paper, we use Krasnoselʹskiiʹs fixed-point theorem in cones and Lyapunovfunctions to study the existence and stability of a positive periodic solution for a class of two-layer heteroassociative networks called bidirectional associative memory (BAM) networks with state dependent delays d x i d t = − a i ( t ) x i ( t ) + ∑ j = 1 m c j i ( t ) f j ( y j ( α j i ( t , y j ( t ) ) ) ) + I i ( t ) , d y j d t = − b j ( t ) y j ( t ) + ∑ i = 1 n d i j ( t ) f i ( x i ( β i j ( t , x i ( t ) ) ) ) + J j ( t ) , where i = 1,2,, n, j =m.