Component Geographic Information System And The Develop Of A Typical Example

(The Institute of Globe Exploration Science and Technology, Jilin University, Changchun 130026, China)Geographic Information System (GIS) is a system of computer software, hardware and data, and personnel to help manipulate, analyze and present information that tied to a spatial location. GIS is a special field of Information Technologies and plays a more and more important role in the information age we are now creating. Components GIS, briefly called ComGIS, is a new generation of GIS based on Components Software and Component-Based Development technologies. We have investigated new software technologies concerning Components-Based Development which include Components Object Model (COM), Distributed Components Object Model (DCOM), Objects Linking and Embedding (OLE), as well as ActiveX. ComGIS is easy to use and integrate with other kinds of software components. ComGIS is a perfect and economical way to make GIS for both professional and non-professional people. ComGIS is the most important technology to implement the next generation Distributed Object WebGIS. ComGIS for the selection of ethanol factory site, developed by Visual Basic and Visual C++ based on SuperMap Objects, comprise the general functions of GIS that is the foundation to analyse the spatial data. The analysis of the selection of ethanol factory site is based upon analysis functions such as Buffer analysis, topo-analysis and so on. The system used the ActiveX for Factory Site Selection that contains the function of factory site selection developed by author and six units of Supermap Objects ActiveX,which is SuperWorkspace, SuperMap, SuperLengend, SuperWdkpManager, SuperGridView and SuperTopo. The ActiveX for Factory Site Selection, namely SiteSelectAnalyst, contains one method with 11 parameters. ActiveX for Factory Site Selection, which can be extend in the future, is designed on Shortest Path Analysis by translate free factory site selection to pointing site selection. Contrast each potential site with others by transportation cost in ten years, so we can select the ethanol factory site efficiently, accurately and quantificationally by using ComGIS for the selection of ethanol factory site. In the future, we will evaluate the cost of building factory,building road and electric power transmission in the ActiveX for Factory Site Selection.