李定凡 的英文怎麼說
中文拼音 [lǐdìngfán]
李定凡
英文
li dingfan-
In the first part, hilbert ' s 16th problem and the studies on it are introduced, and the results of zq - equivariant vector fields of degree 5 ( q = 2, 3, 5, 6 ) are given. in the second part, the definitions of zq - equivariant vector fields and the method of detection functions are stated, and all the forms of nontrivial zq - equivariant planar polynomial vector fields of degree 7 are obtained. in the third part, a concrete numerical example of zt - equivariant perturbed planar hamiltonian system of degree 7 is constructed, and for the unperturbed vector field having maximal number of centers, its global phase portraits are analyzed ( having at least 9 topologically different phase portraits ). then, for a given parameter group, its phase portrait trend is studied
第一部分介紹了hilbert第16問題以及它的研究與發展現狀，給出了近年來利用李繼彬提出的判定函數法得出的z _ q -等變（ g = 2 ， 3 ， 5 ， 6 ）的5次系統關於它的第二部分的研究結果；第二部分介紹了z _ q -等變向量場以及判定函數法，給出了7次平面多項式系統的所有非平凡z _ q -等變向量場具有的形式；第三部分給出了一個7次平面擾動hamilton系統，研究了它的具有最大中心數的未擾動系統（ z _ 7 -等變）的全局象圖，得到了9種不同的拓撲圖形。
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