短語詞組短語upstream approach channel 上游引航道upstream approach channel of lock 上游引航道hfc upstream channel hfc 回傳系統(tǒng)upstream and downstream channel 上下行通道upstream adjacent navigation channel 上游引航道upstream channel in HFC HFC 上行通路debugging of upstream channel 回傳通道調(diào)試 返回 upstream channel