可以将根元素看成是有无穷层的文件柜。
Think of the one root element as being like an endless file cabinet.
大多数机械存储系统是简单的，不是由简单的存储对象序列(诸如书架)组成的。即使是一系列的序列，深度只有一层(好比文件柜)。
Most mechanical storage systems are simple, composed either of a single sequence of stored objects (like a bookshelf) or a series of sequences, one level deep (like a file cabinet).
并指出焊接过程中层间温度的控制，在用热处理控制柜自动控制的同时，再采用便携式远红外测温仪对层间温度进行校核，可以避免层间温度超标现象。
In welding process, the over range of the interpass temperature can be avoided by the control of heat treatment equipment and by the check of the far-infrared temperature instrument.
应用推荐