Introduction to Particles Swarm Optimization
Presented By Mat S
Particle Swarm OptimizationInventors: James Kennedy and Russell Eberhart An Algorithm originally developed to imitate the
motion of a Flock of Birds, or insects Assumes Information Exchange (Social Interactions)
among the search agents Basic Idea: Keep track of
– Global Best (G best)– Self Best (P best)
How does it work? Problem:
Find X which minimizes f(X) Particle Swarm:
– Start: Random set of solution vectors– Experiment: Include randomness in the choice of new states.– Remember: Encode the information about good solutions.– Improvise: Use the ‘experience’ information to
initiate search in a new regions
Particle Swarm Optimization
Particle Swarm Optimization
Vi pbest and Vik
Particle Swarm Optimization
Overview of PSO
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Example
Find minimum value in the function:
(x - 15)^2 + (y - 20)^2 = 0Answer:
x = 15 and y = 20
Now.. Please find minimum value using PSO!
Example
1st iterations
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Example
Iteration X Y (X-15)^2+(Y-20)^2 Gbest1 10 10 125 25
2 10 14.9721 50.27981356 25
3 10 23.77597 39.25795364 15.7092
Example
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0 0 0.2934 1 0 2 0.2934 10 10 2 0.2934 10 10
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Example
4.972 6.464 0.7404 1 6.4637 2 0.7404 10 10 2 0.7404 10 10
8.804 11.445 0.2934 1 11.445 2 0.2934 14.97 14.97 2 0.2934 10 10
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Example
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Particle Swarm Optimization
What is P best ?What is G best ?
Look at the datapbestngbest.xls
Demo
Thank You
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