In this article we apply and discuss El-Desouky technique to derive a generalization of the problem of selecting k balls......

我国高速铁路部分牵引变电所地回流比例长期偏高,加剧了地网结构的腐蚀,甚至烧损接地体和设备。本文根据高速铁路牵引供电系统等效......