portal type

• 门式,门形

portal type的用法和样例：

例句

1. The portal frames are joined at the top by a cross member.
   在门形框架顶部使用一个横撑相连。
2. Dynamic characteristics of the portal frame are also identified from the WPT of low frequency signals.
   低频的部分则可以进行门形构架的系统识别。