Abstract
By constructing suitable Liapunov functionals and estimating uniform upper
and lower bounds of solutions, sufficient conditions are obtained for the
global attractivity of positive periodic solutions of the delay differential
system with feedback control dy/dt=y(t)F(t,y(t−τ1(t)),…,y(t−τn(t)),u(t−δ(t))), du/dt=−η(t)u(t)+a(t)y(t−σ(t)). When these results are applied to the periodic logistic equation
with several delays and feedback control, some new results are obtained.