报告题目：Graph partitions and the controllability of directed signed networks
报告地点：J9-425
报告时间：9月25日下午2：30
报告人简介：纪志坚, 博士, 青岛大学教授, 博士生导师, 山东省杰出青年科学基金获得者, 山东省有突出贡献的中青年专家。1998年硕士毕业于中国海洋大学, 2005年博士毕业于北京大学。先后出访过加拿大阿尔伯塔大学、美国圣母大学、英国布鲁内耳大学、香港城市大学、新加坡国立大学等国内外知名高校。是中国自动化学会控制理论专业委员会委员, 国家自然科学基金的特约评审员, 是首界国家优秀青年基金的会议评审专家。研究方向为多智能体网络系统、切换系统、多机器人系统的分布式协调控制, 复杂网络的分析与控制等。以第一位次获山东省自然科学奖二等奖和三等奖各1项。
报告内容：We investigate the controllability of signed networks which is presented by weighted and directed signed graphs. Graph partitions such as structural balance and almost equitable partitions (AEPs) are studied. We generalize the definition of AEPs to any graphs, directed or undirected, signed or unsigned, with or without edge weights. Based on AEP theory, a graph-theoretic necessary condition is proposed for the controllability of directed signed networks and an algorithm is given for the computation of the coarsest partition. Besides, the upper bound on the controllable subspace is derived when the system is uncontrollable.