Research On Inference For Geography Expert System

The research object of this paper is an expert system building tool called DEST (Distributed Expert System Tool), which is built on Visual C++ 6.0 platform with MFC. After studying the system, improving the inference mechanism and interactive interface of the system in order to meet the users' requirement and amend the weaknesses of the system are done in this paper.For inference mechanism, two aspects of development are introduced in this paper. One is getting data from database during inference process. When inference process needs to get user's answer to continue its reasoning; it can get data from database directly instead of asking user if the user's answers have been stored in the database. This function enhances resource sharing and the efficiency of inference. The other is supporting database operation in expert system. User can do following operations on expert system manager interface, such as viewing the database table, updating content of a cell in a table; inserting or deleting one row in a table. This function enhances the convenience of database maintenance for user.For interactive interface, two aspects of development are introduced in this paper. One is dealing with specific data types in a message which is sent from inference process to interactive interface. It can show correct interface to user according to the specific data types. After obtaining the user's answer, it transfers the answer to predefined format to compose a message, and send the message to inference process. The other one is supporting to show multi-media, which includes image and video. When media information is included in a message sent from inference process, the interactive interface shows the media in a proper way. The type of the image could be JPG, GIF, BMP, PNG and so on; and the type of the video could be AVI and WMV.