Research On A Computer-aided Design System For The Planning Of Irrigation Districts Based On Geographical Information System

With the development platform of Microsoft Visual Basic 6.0, a computer-aided design system based on Geographical Information System for the planning of irrigation districts is developed in this thesis. A new OO(Object Oriented) programming method is adopted in which various software such as Visual Basic, MapInfo Professional 6.0, Microsoft Access and so on are integrated in by the "Automation" technique provided by VB.The determination of the irrigation parameters, dynamic planning of channel drain and corollary building in irrigation area, the parameters calculation of channel and drain design, the evaluation of quantities, economic analysis, the output of design results can be done automatically so as to meet to the requirements of irrigation district planning. The GIS technique is applied to this system for the first time. Electronic map of Maplnfo is introduced into the environment of object oriented by the use of Map X 4.0 module. The operations such as dynamic add, delete and edit of objects can be done real-time dynamically by operators in the environment of object oriented on the present diagram of irrigation distric. At the same time, the spatial-data and attribute-data of irrigation district are managed separately. The spatial-data is used by the file system, whereas, the attribute-data exist in the relevent database. The figures and database are related through the only ID number in order to realize two-way inquiry, so that, the irrigation district layout data are collected automatically. Moreover, in the estimation of the quantity of the irrigation project, an enquiry system about database of the buildings work of irrigation district is established through the statistic of the main buildings of irrigation district in this paper.The programming methods, system structures, developing processes of every part are described in detail in this paper. In the end, the directions of the system are demonstrated in a sample area which lies in the Wudun village, Huaiyin City, Jiangsu Province, the running results show that the system is operated easily, the interface is friendly, the running speed is fast, the planning results is reasonable, which meet the command in advanced, and the system has a preferable practicability.