问答题 翻译：The operation of a gas transmission system that moves gas over a large geographic area and contains several compressor stations and other facilities is a complex control challenge.

问答题 翻译：The success of nontechnical methods averages 4.4% or about one third as success as technical methods.

问答题 翻译：They are built on the same principle as the supertankers the wall of ship is also the wall of the oil tanks.