中文摘要：

钱学森教授曾对＂系统＂给出一个简明的定义：＂系统是指依一定秩序相互联系的一组事物＂.一般说来,系统辨识可以认为是利用已知先验信息和输入–输出数据来建立系统数学模型的科学.经过半个多世纪的发展,系统辨识已成为一个定义较为明确、发展相当成熟的研究领域,在思想方法、理论基础、实际应用等诸多方面都有丰富的研究成果.进入新世纪,伴随着科学技术的突飞猛进,新学科、新研究领域不断涌现,给传统的系统辨识带来了新的挑战与机遇.因而,从这个角度说,系统辨识仍是一个年轻的、朝气蓬勃的学科.本文将讨论系统辨识在新机遇下一些具有潜力的重要方向,提出一些值得关注的热点问题,以此为楔入点,抛砖引玉,希望能引发进一步的讨论.

英文摘要：

The traditional paradigm of system identification employs prior information on system structures and environments and input/output observation data to derive system models.Extensive research and development on its methodologies,theoretical foundation,algorithms,verifications,and applications over the past half century have estab-lished a mature field with a rich literature and substantial benchmark applications.However,rapid advancement in science,technology,engineering,and social medias has ushered in a new era of systems science and control in which challenges and opportunities are abundant for system identification.In this sense,system identification remains an exciting,young,viable,and critical field that mandates new paradigms to meet such challenges.This article points out some potentially important aspects of system identification in these new paradigms,suggests some worthy areas of research focus,and most importantly opens the forum for further discussions.