Study On Water Networks Optimal Rehabilitation Under MAPGIS

Urban water network is an important part of the water-supply systems in our daily life. According with the development of economic, expanding of city and increasing of demand,the developing cities are facing the problem of upgrading and expansion of water distribution system.Because of the huge investment and management cost, optimal upgrading and expansion can save much money and actualize good eenomic and social situation.The accomplishment of this paper is concerned with the practical water networks uprading and expansion engineering of development area in Harbin.With the fast development of the computer technology and the expanding of the social demand, the application of GIS becomes more and more popular. The paper works in the platform of Urban Water Supply Pipeline Network Management System (UWSPNMS) based on Geographical Information System (GIS),and carrys on second time development using high-level programming language Visual Bisic6.0.And constructs tow more power model, water demand forecast model and the pipeline network optimal rehabilitation model.Forecast for water demand is the foundation for rehabilitation.By comparing with several commen methods, BP nervous network is defined. According to the practical situation of development area in Harbin,using the BP nervous network constructed the BP nervous network water consumption forecast model.This model is proved by practice.By studying water distribution theory, conbining with water distribution system of Harbin city development district, the paper establishes current water distribution modeling and the programming water distribution modeling in MAPGIS.Then states imulation and analysis for existing water distribution system settle base of optimal rehabilitation in Harbin water distribution system.According to the rehabilitation methods and economy factors, the paper establishes the function and water distribution systems rehabilitation model. Aiming at the actual instance of Harbin, this paper solves the optimal parameter of water distribution systems.Owing to the discrete character of the pipe diameter, with the function being a multimodal function, and optimal rehabilitation being complex nonlinear programming (NLP) matter, this paper selects genetic algorithm for solvin optimal rehabilitation model. Aiming at traditional GA problems that appeared in practice, this paper ameliorates traditional GA, and applies ameliorative GA to solving optimal rehabilitation model for Harbin water distribution systems.This method were porved to be feasible and applied。...