Machine generated contents note: 1.Introduction -- 2.Loop pairing analysis -- 3.Loop gain margins and stabilizing PID ranges -- 4.Loop phase margins -- 5.Multi-loop PID control based on dRI analysis -- 6.Multivariable PID control based on dominant pole placement -- 7.Optimal multivariable PID control based on LMI approach -- 8.Multivariable PID control for synchronization -- 9.Multivariable process identification.