Application of bispectrmn in leak detection of urban underground gas pipeline;

Due to low pressure,complex circumstance noise and weak leakage signal of the urban underground gas pipeline,it is difficult to detect the signal through general signal processing method which is based on the second-order statistics.

It includes long-distance gas transmission pipeline system and urban gas network system.

Taking Xuanhua for example,the cause ofleakge accident of urban gas network is analyzed,and some preventive measures are put forward.

Methods of load forecast in city gas network;

Taking a city of Liaoning province for example, statistics on leakage accidents of city gas network are made up, the accident causes are analyzed, and some preventive measures are put forward.

Planning and managing cities pipelines network underground is increasingly regarded with the development of geographical information system.

Planning and managing cities pipelines network underground become more and more important with the development of geo-graphical information system.

By means of fault tree analysis method,this paper gives a systemic analysis on the relevant factors which cause the fault of Shanghai city gas transmission and distribution pipeline,and its fault tree is also established.