|
Math Models (MM) are used in every part of GIS. However, the management of MM in Model Base (MB) has some shortage: the grain size of model is often larger, which induces the sharing and expansibility of all model are very poor; the status of MM is static, which 1 induces MB or GIS can not sustain the dynamic creating and flexible management of Math Models; Math Model Base (MMB) is managed with other modules together, which induces system can not manage MMB effectively. The development and utilizing efficiency of GIS MMB are directly affected by these problems which go against the management of the MM and the operation of each function in GIS. Through researching the structure, characteristics of MM in GIS, this paper researched the expressing, management and usage of MM in GIS, with theories about MMB and visual programming technology.1. Through researching the structure of math models in GIS, using model expressing method based on object oriented approach, this paper proposed a concept called "Meta Algorithm", and discussed the classification, basic characteristic and obtained principle of meta algorithm. Then, discussed the concept, functions and characteristic of GIS MMB based on meta algorithm.2. Based on object oriented approach, this paper discussed the organization and classification of math models in GIS MMBS based on meta algorithm, designed logic hierarchy of them. In addition, this paper researched the creating function principle of math model.3. Based on Java program technology, using visualization realizing method, this paper built GIS MMB, and realized the creating process of series-wound and shunt-wound math model visually. Then, this paper built a GIS math model base system platform based on meta algorithm.4. Using GIS MMBS based on meta algorithm, this paper built thematic map MMB and map projection MMB in GIS MMBS based on meta algorithm, then realized the integration in making thematic map and map projection transformation of GIS. With actual using, we proved that the research significance and use value of MMBS based on Meta algorithm is powerful.
|