利用重合度理论,获得了一类具有多个偏差变元的二阶中立型泛函微分方程 d^2/dt^2(u(t)-∑ j=1^ncju(t-rj))=f(u(t))u′(t)+α(t)g(u(t))+∑ j=1^nβj(t)g(u(t-rj(t)))+p(t) 周期解存在性的新的充分条件,改进了已有文献的相关结果.
By using a continuation theorem based on coincidence degree theory and inequality technique, some new sufficient conditions of periodic solutions are established for second-order neutral functional differential equation with multiple deviating arguments as follows d^2/dt^2(u(t)-∑ j=1^ncju(t-rj))=f(u(t))u′(t)+α(t)g(u(t))+∑ j=1^nβj(t)g(u(t-rj(t)))+p(t) The results have improved the related reports in the literatures.