In this paper we begin from the feature of the assembly and disassembly modeling in the virtual maintenance, propose a layeringmethod to assembly and disassembly modeling building.
本文从虚拟维修中装配拆卸模型的基本特点入手，给出了在进行虚拟维修中所需要的模型的层次化组织结构。
2
Introduces the principle and method of quality system files layering and numbering.
介绍了质量体系文件分层和编号的原则和方法。
3
In order to solute these questions, the author puts forward the method of layering turning which is easy to operate, to understand and to master.