北京---上海------------------------------温哥华---多伦多

Bruce Francis就是让我第一次飞起来的那个人。

Francis教授不仅给我买了全程机票，还亲自开车到多伦多机场来接我。

Bruce’s scientific career was remarkably rich and varied. He is considered by many to be one of the most influential researchers in control theory.

He received his Ph.D. degree in Electrical Engineering in 1975 under the supervision of Professor Wonham at the University of Toronto.

In his Ph.D. research with Murray Wonham, Bruce investigated the problem of structural stability of linear multivariable regulators. The object of inquiry was a class of feedback controllers capable of regulating some variables in a control system irrespective of parameter variations and external disturbances. 

In this context, Bruce proved that such a controller must by necessity incorporate an internal model of the external disturbances acting on the system. This so-called “Internal Model Principle” is one of the most profound results of linear control theory.

Internal Model Principle，就是控制理论中著名的“内模原理”，1976年发表在automatica上，是由Francis和Wonham合作完成的。

Wonham在控制界的地位类似于杨振宁在中国物理界的地位，是活着的Kalman，大牛中的最牛，年近90仍然活跃在国际学术界，培养了不少中国研究生。

明天晚上，Wonham大师将通过腾讯视频会议讲解“内模原理”的最新发展，敬请关注。