12.3 A process has the transfer function, G(s) = 2e-²/ (s + 1). Compare the PI controller settings for the fol- lowing design approaches: T2 (a) IMC method (t =

0.2) (b) IMC method (t = 1.0) (c) ITAE performance index (disturbance) (d) ITAE performance index (set point) (e) Which controller has the most conservative settings? Which has the least conservative? (f) For the two controllers of part (e), simulate the closed- loop responses to a unit step disturbance, assuming that G(s) = G(s).