具有奇异和偏差变元的二阶Liénard型中立微分方程的正周期解

Positive Periodic Solutions for Secondorder Neutral Lienard Differential Equations with a Singularity and Deviating Arguments

研究了一类具有奇异和偏差变元的二阶Lienard型中立微分方程的正周期解的存在性通过利用重合度理论和不等式分析技巧，获得了方程正周期解存在性新的充分条件，推广和改进了早期文献的相关结果．最后，给出一个例子，说明所得结果的可行性．

The existence of positive periodic solutions for a class of second-order neutral Lienard differential equations with a singularity and deviating arguments are studied. By employing continuation theorem of coincidence degree theory and inequality analysis technique, some new sufficient conditions of the existence of positive periodic solutions are obtained. Which extend and improve previously known results. Finally, an example is given to illustrate the feasibility of obtained results.