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                Complete classification on center of cubic planar systems with a line of symmetry

                發布者:文明辦作者:發布時間:2022-06-17瀏覽次數:10


                主講人:李鋒 臨沂大學教授


                時間:2022年6月18日14:30


                地點:騰訊會議 241 673 194


                舉辦單位:數理學院


                主講人介紹:李鋒,臨沂大學數學與統計學院教授,碩士生導師,美國《數學評論》評論員,韓國水原大學兼職博士生導師。2012年於中南大學數學與計算科學學院獲理學博士學位。2014年,受國家留學基金資助,赴加拿大西大略大學訪學一年。現主持國家自然科學基金面上項目1項。在Journal of Differential Equations, 中國科學、Nonlinear Analysis等雜誌發表論文20余篇,2016年獲山東省自然科學學術創新獎。


                內容介紹:In this talk, bi-center and bi-isochronous center problems in cubic planar systems which are symmetric with respect to a straight line will be discussed. These systems can be transformed to ones which are symmetric with respect to the $y$-axis and have two symmetric singular points at $(\pm 1,0)$, which can be classified as elementary and nilpotent singular points. A complete classification is given on the centers, including nine conditions for elementary singular points and four conditions for nilpotent singular points. Moreover, six bi-isochronous center conditions are obtained for the elementary singular points.