Post on 13-Apr-2017
Expert Systems Expert systems are based on Artificial intelligenceArtificial Intelligence (AI) is an area of computer science whose goal is to develop computers that can think, see, hear, talk and feel like human beings.AI projects develop Industrial Robots and Intelligent computer software.
One of the practical applications of AI is the development of Expert Systems (ES).
An Expert System (ES) is an knowledge-based information system(KBIS), which uses its knowledge about a specific area to act as an expert consultant to users.
ES provide answers to questions in a very specific problem solving area by making human like inferences.
They must be able to explain their reasoning process and conclusions to a user.
ES can provide decision support to end users in the form of advice from an expert consultant in a specific problem area.
ES can support either operations or management activities. In artificial intelligence, an expert system is a computer
system that emulates the decision-making ability of a human expert.
Expert systems are designed to solve complex problems by reasoning about knowledge, like an expert, and not by following the procedure of a developer.
Components of Expert Systems The components of expert system include a knowledge
Base and software modules that perform inferences on the knowledge and communicate answers to a user’s questions.
Expert Advice
Workstation
User Interfac
e Progra
ms
Inference
Engine Progra
m
Knowledge Base
Expert System Software
The Expert System
Knowledge
Engineering
Workstation
Knowledge Acquisition Program
Expert System Development
Expert and/or Knowledge Engineer
Explanation Program
Query
Advice
Non expert user
Knowledge Base
It containsFacts about a specific subject area
(ex. John is an analyst)Heuristics that express the
reasoning procedures of an expert on the subject (ex. If john is an analyst then he needs a workstation)
Software Modules An ES software package contains an inference engine and
other programs for refining knowledge and communicating with users.
The software modules perform inferences on a knowledge base built by an expert/or knowledge engineer. This provide expert answers on an end user’s questions in an interactive process.
The inference engine program - processes the knowledge (such as rules and facts) related to a specific problem.
User interface programs – used for communicating with end users. It also includes an explanation program to explain the reasoning process to a user if required.
Knowledge acquisition programs – they are not part of the ES but are software tools for knowledge base development.
Expert system shell – is a development tool for developing expert systems.
Advantages Provides consistent answers for repetitive decisions, processes and tasks
Holds and maintains significant levels of information
Encourages organizations to clarify the logic of their decision-making.
Never "forgets" to ask a question, as a human might
Disadvantages Lacks common sense needed in some decision making Cannot make creative responses as human expert would in
unusual circumstances Domain experts not always able to explain their logic and
reasoning Errors may occur in the knowledge base, and lead to wrong
decisions Cannot adapt to changing environments, unless knowledge
base is changed
Application of ES Expert systems are mainly used medicine, engineering,
business etc. For example ES can diagnose illness, search minerals,
recommend repairs and do financial planning. The ES systems asks questions of the user, searches its
knowledge base for facts and rules or other knowledge, explains its reasoning process when asked, and gives expert advice to the user in the subject area being explored.
Inferences The act or process of deriving logical
conclusions from premises known or assumed to be true.
The act of reasoning from factual knowledge or evidence.
Heuristic ( "find" or "discover") refers to experience-based techniques for problem solving
Generally speaking, a heuristic is a "rule of thumb," or a good guide to follow when making decisions. In computer science, a heuristic has a similar meaning, but refers specifically to algorithms.
IE program processes the knowledge(rules and facs) related to a specific problem.