作者讨论了有序Banach空间中非线性二阶积-微分方程u″(t)+Mu(t)一f(t,u(r),(Su)(r))正-周期解的存在性.利用凝聚映射的不动点指数定理,作者在非线性项满足较容易验证的序条件下获得了若干该问题正ω-周期解的存在性定理.这些结果将有限维空间中的部分结果推广到了无穷维空间中.
By using the fixed point index theorem of condensing mapping, under more general conditions on nonlinear term, some existence results o{ positive co-periodic solutions for nonlinear second-order integro-differential equation u"(t)+Mu(t) = f(t, u(t), (Su)(t)) are obtained in ordered Banach spaces. These results partially extend the results in finite-dimensional spaces to that in infinite-dimensional spaces.