The Design Of Rete Algorithm And Its Application In The Intelligent Guidance

Rules engine developed by the reasoning engine is a kind of components embedded in the application, encapsulating a very good reasoning algorithm and conflict resolution mechanisms. It has a very good solution to the inference mechanisms and the efficiency. It has separated from the business application, using as a predefined semantic module to make business decisions. It can accepted the data entry, explain the business rules, and make business decisions in accordance with business rules. At present, there are some world's top commercial business rules engine products such as Ilog JRules, JESS, Drools, all using the Rete algorithm. Rete algorithm uses pattern-matching approach to reasoning, without limiting the number of rules, greatly improving the efficiency with a lot of middle results. It has been considered to be the most efficient inference algorithm so far. But it has some disadvantages as following: In the Rete algorithm, whenαnode is empty, beta nodes join with an emptyαnode, an empty link will happen. In the matching process, the fact are relatively less, when the number of rules increased sharply , there will be many empty link occurred, having seriously impact on the system running time.Therefore, this paper invents a dynamic connection method to improve Rete algorithm, design and implement a rule engine based on the improved algorithm, applied to the diagnosis of physical electrical experiments. With the original algorithm and improved algorithm for the experimental comparison, the improved one made great improvement in the performance . The system is developed in Microsoft Visual C + +6.0 platform, using ODBC database connectivity technology. In this paper, the main contents are as follows:(1) Summarize the latest developments of the rule engine technology and the existing problems. With the Analysis of the mainstream rules engine used in a variety of algorithms, we compare their strengths and weaknesses. We pay more attention on the analysis of the Rete algorithm and point out the disadvantages needing to improve.(2) Dynamic connection method is invented to solve the problem, dynamically add and remove joinnode with emptyαnodes avoiding the empty link in the matching process. So it can execute with shorter time and less space, improving the efficiency of the reasoning.(3)Design a rule engine based on the improved Rete Algorithm, take the experimental fault of resistance measurement of the small light bulbs as an example, develop a small prototype reseasoning system.