广义Liénard系统极限环的存在性与唯一性

The Existence and Uniqueness of Limit Cycles for General Liénard System

就广义Li啨nard系统在允许G(±∞)<+∞,特别是允许limx→+∞F(x)=-∞或limx→-∞F(x)=+∞的情况下,给出了其极限环存在性与唯一性的几组新的充分条件。

For general Liénard system, permitting G(+∞)<+∞,(lim)x→+∞F(x)=-∞ or (lim)x→-∞F(x)=+∞,we gave some new sufficient conditions of existence and uniqueness of limit cycles for general Liénard system.