ZY13000/20/40D掩护式液压支架设计

针对某矿区实际工作面使用工况,对液压支架的总体参数、结构形式、技术特点进行了重点研究,设计了ZY13000/20/40D两柱掩护式液压支架。使用结果表明,该支架结构稳定、支护效果好,能够满足井下工作面使用要求,可以为类似工况的液压支架设计提供相关经验。

Factorizations of groups and related topics

This is a survey of some recent progress in the theory of groups with factorizations. Some of the methods can be used to obtain information about finite groups in general, nilpotent algebras and nearrings.