摘要
本文利用拓扑度理论和某些新技巧，研究了一类中立型时滞模型周期正解的存在性，得到了一些新结果，解决了一个公开问题，并推广、改进了一些已知文献的结果，同时也改正了文［３］中微分运算的错误和定理２．
In this paper,by using theory of topological degree and some new techniques,the existence of a positive periodic solution of the neutral delay model is studied. A new result is obtained. An open question is answered, and results in some known references are extended and improved. In addition,mistake of a differential operation and Theorem 2 in [3] is corrected.
基金
云南省应用基础研究基金资助项目!(97A012G和1999F0017M)
