doublyadv.加倍地；双重地；二倍地doubly heating furnace双重加热炉doubly - fed machine双馈电机doubly connected curve双连结曲线doubly-fed generator双馈发电机doubly-fed induction双馈感应发电机组doubly teleseopie prop双伸缩立柱doubly center matrices双中心矩阵doubly curved reflector双弯曲反射面doubly connected region双连通区域doubly connected domain双连通域