Some are tethered to ships, whereas others are cast free to operate like miniature submarines, although these too need the services of a supportvessel.
有一些与船只绑定，另一些则如同微型潜水艇一样自由航行，但也是需要有供给船只服务的。
2
This phase incorporated device enhancements designed to improve deliverability and the duration ofvesselsupport.
该期试验采用改进的支架设计从而改善支架的输送能力和血管支撑的时间。
3
Structural and mechanical design are performed according to the requirement on the overall design and design input for the reactor pressure vesselsupportof Qinshan Phase II NPP Project.