DepartmentofAutomaticControl;
NorthwesternPolytechnicalUniversity;
Xi'an710072;
P.R.China;
InstitureofAerospaceInformationandControl;
SchoolofElectroniceandInformationTechnology;
ShanghaiJiaotongUniversity;
Shanghai200030;
P.R.China;
DepartmentofAutomaticControl;
NorthwesternPolytechnicalUniversity;
Xi'an710072;
P.R.China;