The historical reason here is simple – mechanical design was a key element of manufacturing for many years.
历史原因很简单——机械设计多年以来一直是制造企业的一大要素。
2
Power element: an energy conversion device for converting mechanical energy output from a prime mover into a liquid pressure energy.
动力元件：把原动机输出的机械能转变为液体压力能的能量转换装置。
3
The model of L4-L5 functional element was chosed from"mechanical visiual human of China"model database. The intervertebral disk was replaced by the new type artificial disk.