Gis-based City Gas Emergency Decision Support Model

The development of GIS and DSS peered a new research scale for solving semi-constructed and non-constructed decision-making problems by applying theories and approaches correlating to DSS using space information technology. This paper mainly investigates the emergencies of city gas pipeline by means of combining GIS and DSS to provide important position information, space analyzing function and objective visual decision application method, which enhanced the ability of treating space information and improved the expressing effect.In this paper, the organizing style of "request analysis-technology support-model analysis-decision making analysis" is applied to discuss the decision-making model of city gas pipeline based on GIS. Its content includes several aspects as follows:1) Investigating the present status of correlating fields. Achievements of multi-aspect applications of this field were concluded after researching theories of GIS and DSS home and abroad. Also, the development and shortage of city gas pipeline in this field were analyzed.2) Industrial accidental organization system, basic fulfilling procedure, accident response, first-aid repair and rescue were discussed in detail by analyzing the features and general procedure of gas pipeline emergency. According to the decision on emergencies, combined with GIS, five aspects of the decision were discussed which are alarming, disaster reducing, treating, rescuing and recovering.3) The GIS and DSS and their relating definition and theories were introduced. The technology support and data realization of city gas pipeline include system composition, space data model, data code, classification and exploring approach and platform framework.4) Models of small-hole leakage, pipe leakage and ordinary leakage were chosen in this research according to the features of gas pipeline accidents which are optionally applied due to different leaking diameters to estimate leakage amount. Then one can simulate the gas diffusion by combining the leakage amount with Gaussian Plume model. The visualization of diffusion was realized by applying VC++and MapX.5) When leakage or diffusion occurs in gas pipeline, decision maker can see the affected area objectively, since the GIS space analysis function is applied in buffer analysis and layer summation which overlaps the diffusion map on geographic map that has point, line and plane elements. The statistic data can be use in decision making.