The Riccati equation method is used to establish some global solvability criteria for a classes of Lane–Emdem–Fowler and Van der Pol type equations. Two oscillation theorems are proved. The results obtained are applied to the Emden–Fowler equation and to the Van der Pol type equation.

中文翻译：

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一类二阶非线性常微分方程的全局可解性和振荡准则，包含一些重要的经典模型

Riccati 方程方法用于为一类 Lane-Emdem-Fowler 和 Van der Pol 类型方程建立一些全局可解性准则。证明了两个振荡定理。获得的结果应用于 Emden-Fowler 方程和 Van der Pol 型方程。