关于Liénard系统的正半轨线与特征曲线相交的充要条件

THE NECESSARY AND SUFFICIENT CONDITIONS OF THE GENERALIZED LIéNARD SYSTEM FOR INTERSECTION OF POSITIVE SEMIORBITS WITH CHARACTERISTIC CURVE

讨论了Li啨ｎａｒｄ系统 x =y -F(x) , y =- g(x)过平面上任意一点的正半轨线与特征曲线 y =F(x)相交的充要条件 ,对Villari和Zanolin在文

In this paper, we obtain some sufficient and necessary conditions of the Liénard system =y-F(x),=-g(x) for intersecton of positive semiorbits with characteristic curve y=F(x) through any point on plane. This result answers the question in Villari and Zanlin's paper [1].