Expert Systems

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Expert Systems - Definition

Created from research into Artificial Intelligence – AI

Also known as knowledge based systems. Based on Facts & RulesFacts & Rules.

A system that attempts to replicate a human expert in solving specific problems or making decisions

Expert System ComponentsComprises of 3 things

Knowledge BaseExperts in the field are interviewed. Information collected from many sources. Information is entered into the knowledge base.

Inference EngineAlgorithms that interrogate the knowledge base.

HCIAllows anyone to use system. Must be clear and easy to use – often Natural Language

Expert System - features

Limited area of expertise

Rule based

Can operate with uncertain data

Delivers reasoned advice

Expert Systems – main components

Knowledgebase

Knowledgebase

Inferenceengine

Inferenceengine

InterfaceInterface

ExpertSystemExpertSystem

rules

facts

computer program

inputsoutputs

Expert systems - uses

Medical diagnosis

Fault diagnosis

Geological surveys

Social services

Industrial uses

Expert Systems – case studies and demos

ELSIE – 1990’s quantity surveying tool

http://www.exsys.com/demomain.html

For demos of the following expert systems, including:

Cessna Diagnostic & Repair Systems Immigration and Naturalization Service Environmental Compliance Self Appraisal Weather Instrument Product Selector State of Wisconsin - Public School Disciplinary Action Advisor DriveRight Trip 500AL Hardware Installation Expert System

Expert Systems - benefits

Can be faster than human experts

Cost reduction over alternative diagnostics

High reliability possible

Consistent, rationalised decisions & results

Encapsulates and distributes expertise

Can be used as a repository of knowledge

Expert Systems - Limitations

Can make mistakes and will not learn from them

Expert knowledge is hard to obtain. Systems work best when problem is clearly defined and rules are clearly stated

Can create a dearth of skills

Stifles creative processes and exception handling