%0 Journal Article
%T The Bifurcation of Limit Cycles for a Planar Seventh Order Differential System<br>一类7次微分自治系统的极限环分支
%A DU Chaoxiong
%A <br>杜超雄
%J 系统科学与数学
%D 2010
%I 
%X In this paper, a class of planar seventh order differential system is investigated. By introducing two appropriate transformations of system and calculating general focal values carefully, the infinity and two elementary focuses $(\frac{1}{2},\frac{\sqrt{3}}{6}),(-\frac{1}{2},-\frac{\sqrt{3}}{6})$ become three general 5th fine foci at the same time and moreover 15 limit cycles including 10 small limit cycles from two elementary focuses and 5 large limit cycles from the infinity can occur under a certain condition.
%K Bendixson homeomorphous transformation
%K general focal values
%K limit cycle
%K bifurcation<br>Bendixson
%K 同胚变换
%K 广义焦点量
%K 极限环
%K 分支.
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=6E709DC38FA1D09A4B578DD0906875B5B44D4D294832BB8E&cid=37F46C35E03B4B86&jid=0CD45CC5E994895A7F41A783D4235EC2&aid=71C1FE70529F500E8332D75AE7F95416&yid=140ECF96957D60B2&vid=F3090AE9B60B7ED1&iid=F3090AE9B60B7ED1&sid=2B78D85EBFEED708&eid=C4160F9DDB7598AD&journal_id=1000-0577&journal_name=系统科学与数学&referenced_num=0&reference_num=0