The behavior of the coronary artery systems (2) and (3) with different time-varying delays and disturbance ω₁(t) = (0.3 sin(40t),0.1 sin(30t)): (a) time response of x₁,y_a1,y_c1,y_e1, (b) time response of x₂,y_a2,y_c2,y_e2, (c) error state of e_a,e_c,e_e when 0 ≤ t ≤ 10, and (d) error state of e_a,e_c,e_e when 5 ≤ t ≤ 100.