Title: Expert Systems

Presentation By:Muhammad AamirMuhammad AamirRoll no:0303

Expert Systems

“..An intelligent computer program that uses knowledge and inference procedures to solve problems that are difficult enough to require significant human expertise for their solution..” (Feigenbaum 1982)

Expert System

Basic concept of expert system : User supplies facts or other information to the expert system

and receives expert advice or expertise in response.

Internally, the expert system consists of two main components :

the knowledge-base contains the knowledge the inference engine draws conclusions from the knowledge

Knowledge-base

Inference Engine

User

Expertise

Expert System

Facts

Expert System Functionality• Assist human expert when integrating various decisions

• Replace human expert decision making when not available

Expert systems : programming computers to make decisions in real-life situations (for example, some expert systems help doctors diagnose diseases based on symptoms)

Applications of Expert Systems

Peachtree:Used by accountant for

making Database,Financial documents

Applications of Expert Systems

PROSPECTOR:Used by geologists to

identify sites for drilling or mining

PUFF:Medical system for diagnosis of

respiratory conditions

Components of an Expert System

• The knowledge base is the collection of facts and rules which describe all the knowledge about the problem domain

• The inference engine is the part of the system that chooses which facts and rules to apply when trying to solve the user’s query

• The user interface is the part of the system which takes in the user’s query in a readable form and passes it to the inference engine. It then displays the results to the user.

Why use Expert Systems?

• Experts are not always available. An expert system can be used anywhere, any time.

• Human experts are not 100% reliable or consistent

• Experts may not be good at explaining decisions

• Cost effective

Problems with Expert Systems

• Limited domain• Systems are not always

up to date, and don’t learn

• No “common sense”• Experts needed to setup

and maintain system

Limitations of Expert Systems• Limited to relatively narrow problems• Cannot readily deal with “mixed”

knowledge• Possibility of error• Cannot refine own knowledge base• Difficult to maintain• May have high development costs• Raise legal and ethical concerns

Any Queries

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