Improved control of delayed measured systems
  In this paper we address the question how the control of delayed measured chaotic systems can be improved. Both unmodified OGY control and difference control can be successfully applied only for a certain range of Lyapunov numbers depending on the delay time. We show that this limitation can be overcome by at least two classes of methods, by rhythmic control and by the memory methods linear predictive logging control (LPLC) and memory difference control (MDC). 
Jens Christian Claussen and Heinz Georg Schuster (University Kiel,   Germany)