Fuzzy logic

Post on 12-Nov-2014

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Fuzzy logic

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AAPRESENTATION PRESENTATION

ONONFUZZY LOGICFUZZY LOGIC

PREPARED BY:-PREPARED BY:-

PATEL SAHIL(06DME025)PATEL SAHIL(06DME025)

SAMA RIYAZ(06DME026)SAMA RIYAZ(06DME026)

ARTIFICIAL INTELLIGENCE

“AI is the science of making machine do things that would require intelligence if done by man.”

The logic which we use to have fast response in a critical situations is fuzzy logic.

Fuzzy Logic: What is it???

Fuzzy logic is a superset of conventional (Boolean) logic that has been extended to handle the concept of partial truth - truth values between "completely true" and "completely false"

It is a different way of looking at the world. It is a superset of Boolean logic! It deals with “shades of gray!”

A Better Method to Deal Withthe Real World

Not just “True” and “False.” Takes on a range of values – True – Mostly True – Half True – Kind of True – False Values range from 0 to 1. – Including decimal values (0.2, 0.7, etc.)

Fuzzy Logic Process

“Crisp” Input

“fuzzy” input

Fuzzification

Fuzzy logic

“Fuzzy” OutputDe-Fuzzification

“Crisp” Output

Fuzzification

How tall is Kevin? Very Tall? Tall? Average? Short? Very Short?

How tall is Kevin?

Very Tall (7 feet)? Tall (6 feet)? Average (5 feet)? Short (4 feet)? Very Short (3 feet)?

Some examplesSome examples

If you are 5 feet: Very tall - 0% - Very Tall (7 feet)? Tall - 0% - Tall (6 feet)? Average 100% -Average (5 feet)? Short - 0% - Short (4 feet)? Very Short - 0% - Very Short (3 feet)?

If you are If you are 5½ feet:5½ feet: Very tall - 0%Very tall - 0% -Very Tall (7 feet)?-Very Tall (7 feet)? Tall - Tall - 50%50% --Tall (6 feet)?Tall (6 feet)? Average - Average - 50%50% --Average (5 feet)?Average (5 feet)? Short - 0%Short - 0% -Short (4 feet)?-Short (4 feet)? Very Short - 0%Very Short - 0% -Very Short (3 feet)?-Very Short (3 feet)?

Not in boolean logicNot in boolean logic

De-Fuzzification Two Methods:-1) Winner Take All

-Output “Hard Right” = 70%- It is the winner!- Output = 100 (from output mapping)- Looses some of the smoothness of fuzzy logic.

2) Weighted Average - Output “Hard Right” = 70% - Output “Left” = 20% - Output = 73.3

Benefits of Fuzzy System Modeling

Ability to Model Highly Complex Business Problems Ability to Model System Involving Multiple Experts Reduce Model Complexity Improve Handling of Uncertain and Possibilities

Common Objections to Fuzzy Logic

Much of the opposition to fuzzy logic is based on the misconception

Fuzzy logic invites the belief that the modeling process generates imprecise answers

Applications

ABS Brakes Expert Systems Control Units Bullet train between Tokyo and Osaka Video Cameras Automatic Transmissions

Conclusion

The exact directions and extent of future developments will be dictated by advancing technology and market forces

Fuzzy logic is a tool and can only useful and powerful when combined with Analytical Methodologies and Machine Reasoning Techniques

Any Question?????

Thank you