1. The Coordination of Parallel Search with Common Components
Stephen Chen and Gregory Pitt York University

2. Heuristic Search Search Operators Control Strategies June 23, 2005
IEA-AIE 2005

3. An Obvious Failing
Point search operators do not have historical information!
June 23, 2005
IEA-AIE 2005

4. Search Operator Strategies
What can be improved?
What is worth keeping?
June 23, 2005
IEA-AIE 2005

5. Random Local Minima
June 23, 2005
IEA-AIE 2005

6. Simulated Annealing
June 23, 2005
IEA-AIE 2005

7. Summary Random search space, random search strategy
All the intelligence of simulated annealing is in the control strategy
June 23, 2005
IEA-AIE 2005

8. Distribution of Local Minima (Boese)
Length
Average distance from other local minima
June 23, 2005
IEA-AIE 2005

9. “Big-Valley” – Globally Convex
June 23, 2005
IEA-AIE 2005

10. “Directed” Simulated Annealing
June 23, 2005
IEA-AIE 2005

11. Coordination with Common Components
June 23, 2005
IEA-AIE 2005

12. Restricted Mutations Parent 1 1 1 1 0 0 1 0 1 1 1
Common
Uncommon
Uncommon
June 23, 2005
IEA-AIE 2005

13. TSP Results Instance n=1 n=2 n=4 n=8 pcb1173 8.55 8.07 5.08 8.05 4.88
7.49
4.40
fl1400
5.82
4.33
3.15
3.58
2.45
2.86
1.94
fl1577
10.97
9.09
2.48
7.69
2.19
6.91
1.49
June 23, 2005
IEA-AIE 2005

14. Summary Globally convex search space, “respectful” search operator
Add some intelligence to the search operator
June 23, 2005
IEA-AIE 2005

15. Conclusion
The preservation of common components can improve the performance of parallel search procedures in globally convex search spaces
June 23, 2005
IEA-AIE 2005