1·However, the auxiliary lock is not equipped with tow haulage equipment, so double lockage tows require special pull boat assistance.
但是，辅助船闸没有牵引设备，因此双闸拖轮需要有特殊的牵引船协助。
2·Research on continuous ore drawing and haulage equipment for underground metal mines has widely been done in main foreign countries with mining industry.
国外主要矿业国家对地下金属矿山连续出矿运矿设备进行了深入的研究。