Article ID: | iaor20051466 |
Country: | United Kingdom |
Volume: | 55 |
Issue: | 7 |
Start Page Number: | 728 |
End Page Number: | 736 |
Publication Date: | Jul 2004 |
Journal: | Journal of the Operational Research Society |
Authors: | McCormick G., Powell R.S. |
Keywords: | scheduling, optimization: simulated annealing |
The scheduling of pumps for clean water distribution is a partially discrete non-linear problem with many variables. The scheduling method described in this paper typically produces costs within 1% of a linear program-based solution, and can incorporate realistic non-linear costs that may be hard to incorporate in linear programming formulations. These costs include pump switching and maximum demand charges. A simplified model is derived from a standard hydraulic simulator. An initial schedule is produced by a descent method. Two-stage simulated annealing then produces solutions in a few minutes. Iterative recalibration ensures that the solution agrees closely with the results from a full hydraulic simulation.