Research On Application Uncertainty Reasoning In Diseases And Pests Expert System

With the rapid development of urbanization, at the same time of building material and spiritual, people are increasingly high requirements on the ecological environment. Urban green belt has played an important role of protecting city's ecological environment. In recent years, the green belts are constantly infringed by diseases and pests, which are so overwhelmed by green belt. According to statistics of gardening sectors, over ninety percent of acer saccharum were infringed by Anoplophora glabripennis of Harbin City in 2008. In 2009, the resurgence of pests caused severe economic losses.Based on the description above; it established practical and efficient diseases and pests expert system for effective prediction, diagnosis and prevention.According to the characteristics of diseases and pests which are in green belts, the article chooses way of non-automatic knowledge acquisition, and through knowledge extraction, knowledge conversion, knowledge input and knowledge test, which ensure the accuracy and completeness of knowledge. It uses production representation as knowledge representation, and constructs knowledge bases of the diseases and pests in green belt. It establishes practical and standard pest prediction models, so that forecasting of pests is more accurate.In the process of diseases and pests diagnosis and prevention, uncertain symptoms are pervasive. However, the uncertainty will have a direct impact on the final conclusions. Therefore, the system uses the uncertainty reasoning mechanism, with the analysis of certainty factor CF model and subjective Bayes model, which establishs the credibility of subjective Bayes model. The model eliminates the credibility the dependence of the CF model and subjective Bayes model with prior probability P(H), and uses in pest and disease diagnostic reasoning.It is a system with diseases and pests diagnosis, prediction, and prevention, the basic information about tree species and diseases and pests. It achieves scientific and intelligent management of diseases and pests in green belts. The system uses B/S architecture, in the front of today's popular JSP technology and background is MySQL database management system which provides powerful support with data connections, access and control.