PSO

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Particle Swarm Optimization
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Study their behavior.....
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How does a particle move ?
Component in the direction of previous motion
New Motion
Component in the direction of personal best
Component in the direction of global best
Component in the direction of local best
Global Best
Local Best
Personal Best
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The Anatomy of a Particle

• A particle is composed of
• - three vectors

Position Velocity Best Position
- Two fitness values
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The Neighborhood Principle
3
8
1
7
4
5
9
2
6
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Social Network Structure
Ring Neighborhood Structure ( pbest version of
PSO )
Star Neighborhood Structure ( gbest version of
PSO )
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Position and Velocity Adjustment
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Velocity Vectors Parameters
c1 c2 are positive acceleration constants.
Inertia Weight
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Initialize Swarm
Mutate Swarm
Evaluate Fitness
Synchronous PSO Algorithm
gbest Replacement
Update Position
with Mutation
pbest Replacement
Update Velocity
gbest Best Solution
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Change the initial parametersand start with new
parameters
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13
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