Expert Systems: Applications, Advantages, and Architecture

Expert Systems

Expert systems are software applications designed to mimic the decision-making abilities of a human expert. They store specialized knowledge within a specific field and utilize logical deduction to solve problems.

Applications

Expert systems find wide applications, particularly in business management. Most companies utilize computers for data processing, accounting, financial decisions, and planning. These tasks involve extensive information processing and numerical operations, making them ideal environments for expert system implementation.

Application Areas

  • Military
  • Telecommunications
  • Chemistry
  • Law
  • Aviation
  • Geology
  • Agriculture
  • Electronics
  • Transportation
  • Education
  • Medicine
  • Industry
  • Finance
  • Management

Advantages

Expert systems excel at processing large volumes of information, a task that can overwhelm human analysts. While humans filter data for relevance, expert systems analyze all available information due to their superior processing speed, leading to more comprehensive decisions.

Limitations

  • Require reprogramming to update information
  • Can be expensive to develop and maintain
  • Inflexible and struggle with unstructured information
  • Limited ability to solve general problems
  • Lack common sense for complex or ambiguous situations

Basic Architecture

Knowledge Base

This component stores domain-specific knowledge, often codified as rules. A rule is a conditional statement linking information in the antecedent (condition) to information in the consequent (result).

Basic Facts

This component holds facts about a specific problem, gathered during a consultation. The system compares these facts with the knowledge base to infer new facts.

Inference Engine

This module simulates human reasoning. It uses the knowledge base and basic facts to deduce new information.

Explanation Subsystem

This module allows the system to explain its reasoning, answering user questions and clarifying how it reached a conclusion.

User Interface

The user interface facilitates natural language interaction between the user and the system. A key requirement is the ability to ask questions.

Tasks Performed by an Expert System

Monitoring

This involves continuously comparing input signals or data with established norms or standards. In predictive maintenance, expert systems serve as diagnostic tools, determining the operational status of complex systems and anticipating potential incidents.

Design

Design involves creating a detailed description of an artifact that meets specific criteria using various knowledge sources. This can include engineering design, industrial design, and other forms.

Planning

Planning involves creating sequences of actions to achieve a goal. Expert systems in planning address challenges like unpredictable consequences, multiple considerations, sub-plan interactions, uncertainty, and diverse data sources.

Control

This involves interpretation, diagnosis, and repair sequencing to guide a process or system. Control systems can be open-loop (requiring operator feedback) or closed-loop (autonomous).

Simulation

Simulation involves creating computer models based on facts, observations, and interpretations to study behavior. Expert systems are well-suited for simulation due to their ability to mimic complex human reasoning.