These asphalts are used in the construction of built-up roof coverings, the coating of undergroundtransmission pipes and other applications.
这些沥青可用于组合屋面复盖层的建造、地下输送管线的涂层及其他应用领域。
2
Because of the longer repair time for undergroundtransmission systems, expensive duplication facilities are sometimes installed to reduce the risk of overlap-ping outages4.
由于地下输电系统的修理时间较长，因此有时就安装双套重复设施以降低重叠停电的危险。
3
As the CANBUS transmission distance is limited, it is necessary to design a CANBUS repeater which ADAPTS to long-distance undergroundtransmission to store and forward the CAN signals.