報告題目：On the Phases of Sectorial Operators
報 告 人：于天秋教授 黑龍江大學
報告時間：2020年11月13日 15:00-16:00
報告地點：騰訊會議 ID：428 239 511 密碼：123456
校内聯系人：張遠航 zhangyuanhang@jlu.edu.cn
報告摘要：
In this talk, we define the phases of a sectorial operator based on numerical range and to clarify some of their properties. For the class of operators of the form strictly positive plus compact, we establish a majorization relation between the phases of the spectrum of AB and the phases of two sectorial operators A and B. This is then applied to give a necessary and sufficient condition for the invertibility of I+AB with both gain and phase information of two sectorial operators A and B, which plays a crucial role in feedback stability analysis.
報告人簡介：
于天秋，黑龍江大學數學科學學院教授, 碩士生導師, 2011-2017年先後在大連理工大學和香港科技大學從事博士後和訪問學者工作. 主要從事算子理論、Hilbert空間上線性系統魯棒穩定性等方向的研究. 研究成果主要發表在SIAM Journal on Control and Optimization， PAMS, System& Control Letters，Journal of The Franklin Institute等期刊。
