What is an Expert System?
Expert system is an artificial intelligence program that has expert-level knowledge about a particular domain and knows how to use its knowledge to respond properly. In this context, a domain refers to the area within which the task is being performed.
Ideally the expert systems should substitute a human expert. Edward Feigenbaum of Stanford University has defined expert system as “an intelligent computer program that uses knowledge and inference procedures to solve problems that are difficult enough to require significant human expertise for their solutions. “
The source of knowledge for expert systems may come from human experts, books, magazines and/or even the internet. Expert systems are also known as knowledge-based systems or knowledge-based expert systems.
Components of Expert Systems
Figure [ 1 ] Expert System
The expert system consists of two major components: knowledge-base and inference engine. As show in Figure 1 above, these roles of these components are: 1. The knowledge-base contains the domain knowledge which is used by the inference engine to draw conclusions. 2. The inference engine is the generic control mechanism that applies the axiomatic knowledge to the task-specific data to arrive at some conclusion.
When a user supplies facts or relevant information of query to the expert system, he receives advice or expertise in response. That is, given the facts, it uses the inference engine which in turn uses the knowledge-base to infer the solution.
Characteristics of Expert Systems 1. High performance: They should perform at the level of a human expert. 2. Adequate response time: They should have the ability to respond in a reasonable amount of time. Time is crucial especially for real time systems. 3. Reliability: They must be reliable and should not crash. 4. Understandable: They should not be a black box instead it should be able explain the steps of the
Bibliography: 1. Expert Systems http://intelligence.worldofcomputing.net/ai-branches/expert-systems.html#.UbmRt5xWKFf 2. Rule Based Expert Systems http://intelligence.worldofcomputing.net/expert-systems-articles/rule-based-expert-systems.html#.UbmU9pxWKl6