为探究吕家坨井田地质构造格局,根据钻孔勘探资料,采用分形理论和趋势面分析方法,研究了井田7......

为探究吕家坨井田地质构造格局,根据钻孔勘探资料,采用分形理论和趋势面分析方法,研究了井田7......

By utilizing a fixed point theorem on cone, some new results on the existence of positive periodic solutions for nonauto......

This paper is to solve several problems on the global attractivity of the zero solution of the nonautonomous difference ......