%0 Journal Article
%T MULTIPLE PERIODIC SOLUTIONS TO A CLASS OF SECOND-ORDER FUNCTIONAL DIFFERENTIAL EQUATIONS<br>一类二阶泛函微分方程的多重周期解
%A ZHENG Dongmei
%A LU Shiping
%A <br>郑冬梅
%A 鲁世平
%J 系统科学与数学
%D 2010
%I 
%X By means of variational principle and $Z_{2}$ group index theory, we obtain the existence of multiple periodic solutions to second-order functional differential equations $x'(t-\tau)+c(x(t)-x(t-2\tau))'-x(t-\tau)+\lambda f(t,x(t),x(t-\tau),x(t-2\tau))=0$.
%K Variational structure
%K $Z_{2}$ group index theory
%K critical point
%K the Palais-Smale condition
%K multiple periodic solutions<br>变分原理
%K $Z_{2}$不变群指标
%K 临界点
%K P.S.条件
%K 多重周期解.
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=6E709DC38FA1D09A4B578DD0906875B5B44D4D294832BB8E&cid=37F46C35E03B4B86&jid=0CD45CC5E994895A7F41A783D4235EC2&aid=3F034EB0475CF1826149116F81D34453&yid=140ECF96957D60B2&vid=340AC2BF8E7AB4FD&iid=38B194292C032A66&sid=0918129209B14F3E&eid=73648F51F187AC5E&journal_id=1000-0577&journal_name=系统科学与数学&referenced_num=0&reference_num=9