Robust facility location with mobile customers

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2011
Gül, Evren
In this thesis, we study the dynamic facility location problem with mobile customers considering the permanent facilities. Our general aim is to locate facilities considering the movements of customers in time. The problem is studied for three objectives: P-median, P-center and MINMAX P-median. We show that dynamic facility location problem is a large instance of a static facility location problem for P-median and P-center objectives. In the problem, we represent the movements of each customer in time with a time series. Using clustering approaches, we develop a heuristic approach for the problem with P-median objective. K-means algorithm is used as a clustering algorithm and dynamic time warping is used in order to define similarities between the customer time series. Solution method is tested on several experimental settings. We obtain results, which differ at most 2% from the optimal, in small computation times. Generally, in the literature, MINMAX P-median is solved with a heuristic depending on scenarios planning (see Serra and Marianov, 1998). The heuristic finds an initial solution according to scenarios, later the initial solution is tried to be improved. We provide a bounding procedure on the solution of the problem. The bounds can be used by decision maker to judge the solution quality before proceed. The bounding procedure is also analyzed in different experimental settings.

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Citation Formats
E. Gül, “Robust facility location with mobile customers,” M.S. - Master of Science, Middle East Technical University, 2011.