Gis Environment, The Failure Of Water Supply Pipe Network Decision-making System

Geographic Information System (GIS) is introduced radically in this thesis. Optimized schemes of valve shutdown and hydro dynamical calculations called decision-making project under GIS environment as the accident of urban water supply network happenstance are key introduced. And design method, whole construction and key technologies of Decision-making system under GIS environment when the accident of urban water supply network happenstance (GIS-GF) are analyzed at the same time.GIS-GF are applied programs developed by MmpBasic language of second develop tool in Maplnfo, and by the way of integrating maps, that is to say, map window in Maplnfo is integrated into Visual Basic program by Visual Basic language. In this system, spatial data and graphics of water supply network are managed by Maplnfo tables. Characteristic data of water supply network are stored in the Access data basement. And they are connected by OLE method and put into some operations.Establishment of optimized module of valve shutdown scheme is the key part in the GF-GIS system, and is the foundation of realizing hydro calculation module. Valve shutdown module is established by BFS algorithm in Plot Theory, basing on pological relationship of water supply network, it implemented optimized valve attemper. Hydro dynamics status when the accident of urban water supply network happens or after valve shutdown are simulate by hydrodynamic calculations of network with lower hydro-pressure.After system analysis, constructions and functions of GF-GIS are put forward according software engineering methods. From narration of the up-to-date manned system and then on, applications of these function modules are showed by steps.