Inference engine

6,893 views

Published on

Brief introduction on Inference Engine in Expert System.
Forward & Backward Chaining, KBS, KWS

Published in: Education, Technology
0 Comments
1 Like
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total views
6,893
On SlideShare
0
From Embeds
0
Number of Embeds
8
Actions
Shares
0
Downloads
387
Comments
0
Likes
1
Embeds 0
No embeds

No notes for slide

Inference engine

  1. 1. Presented By:Abhishek Pachisia - 090102801Akansha Awasthi - 090102003 B.Tech – I.T.
  2. 2.  An Expert system is a computer system that emulates the decision-making ability of a human expert It is divided into two parts,  Fixed, Independent : The Inference Engine,  Variable: The Knowledge Base Engine reasons about the knowledge base like a human.
  3. 3.  Computer program that tries to derive answers from a knowledge base. Brain of Expert System Inference commonly proceeds by  Forward chaining  Backward chaining
  4. 4. ﴾ Grandfather (Tom -Marry)﴾ Father (Tom -Jack)﴾ Father (Jack -Mary) Here there are two facts ₪ Tom is the father of Jack ₪ Jack is the father of Mary
  5. 5.  An interpreter  The interpreter executes the chosen agenda items by applying the corresponding base rules. A scheduler  The scheduler maintains control over the agenda by estimating the effects of applying inference rules in light of item priorities or other criteria on the agenda. A consistency enforcer  The consistency enforcer attempts to maintain a consistent representation of the emerging solution.
  6. 6.  Conflict resolution  If there are activations then select the one with the highest priority else done Act Sequentially  Perform the actions.  Update the working memory.  Remove the fired activations.
  7. 7.  Match  Update the agenda - Checking if there are activations if their LHS is no longer satisfied. Check for halt - Two commands tell that action is over.  Break  Halt
  8. 8. ¥ Forward chaining¥ Backward chaining
  9. 9.  Takes rule and if its conditions are true adds its conclusion to working memory until no more rules can be applied If the conditions of the rule if A and B then C are true then C is added to working memory. In forward chaining the system simply test the rules in the order that occurs therefore rule order is important.
  10. 10.  The backward chaining inference engines tries to prove a goal by establishing the truth of its conditions The rule if A and B then C the backward chaining engine will try to prove C by first proving A and then proving B. Proving these conditions to be true may well invoke further calls to the engine and so on.
  11. 11. It is a computer program to solve complex problems. Reasons Uses knowledgeKnowledge is acquired represented using variousknowledge representation Techniques Rules, Frames and Scripts. User Inference Knowledge Interface engine base
  12. 12. There are specialized systems for knowledge workers To help them to create new knowledge To ensure that this knowledge is properly integrated into the businessCritical Key roles of knowledge workers Keeping the current knowledge Serving as internal consultants regarding the areas of their knowledge Acting as change agentsKnowledge work systems require strong links To external knowledge bases in addition to specialized hardware and software.
  13. 13. CAD/CAM systems: Computer-aided design (CAD) and Computer-aided manufacturing (CAM) systems automate  The creation and  Revision of designs, using computers and sophisticated graphics software. They provide  Engineers,  Designers, and  Factory managers with precise manufacturing control over industrial design and manufacturing
  14. 14. Virtual reality systems: These use interactive graphics software to  Aid drug designers,  Architects,  Engineers, and  Medical workers by presenting precise, three-dimensional simulations of objects.
  15. 15. Investment workstations: These are high-end PCs used in the financial sector  To analyze trading situations instantaneously and  Facilitate portfolio management.

×