1. Department of Automation, Xiamen University, Xiamen, China, 361102 (e-mail: laiaiwen123@gmail.com)
2. Laboratoire d'Ingnierie des Systmes Automatis's, Univ Angers, LARIS, Angers, France, 49000 (e-mail: sebastien.lahaye@univ-angers.fr)
3. Institute of Mathematics, Czech Academy of Sciences, Brno, Czech Republic, 616 62 (e-mail: komenda@ipm.cz)