Locations on a line and generalization to the dynamic p-medians

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Date

2012

Author

Güden, Hüseyin

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This study deals with four location problems. The first problem is a brand new location problem on a line and considers the location decisions for depots and quarries in a highway construction project. We develop optimal solution properties of the problem. Using these properties, a dynamic programming algorithm is proposed. The second problem is also a brand new dynamic location problem on a line and locates concrete batching mobile and immobile facilities for a railroad construction project. We develop two mixed integer models to solve the problem. For solving large size problems, we propose a heuristic. Performances of models and the heuristic are tested on randomly generated instances plus a case study data and results are presented. The third problem is a generalization of the second problem to network locations. It is a dynamic version of the well known p-median problem and incorporates mobile facilities. The problem is to locate predetermined number of mobile and immobile facilities over a planning horizon such that sum of facility movement and allocation costs is minimized. Three constructive heuristics and a branch-and-price algorithm are proposed. Performances of these solution procedures are tested on randomly generated instances and results are presented. In the fourth problem we consider a special case of the third problem, allowing only conventional facilities. The algorithm for the third problem is improved so that generating columns and solving a mixed integer model are used repetitively. Performance of the algorithm is tested on randomly generated instances and results are presented

Subject Keywords

Industrial location., Store location., Roads, Heuristic algorithms., Standard deviations., Operations research.

URI

http://etd.lib.metu.edu.tr/upload/12614934/index.pdf
https://hdl.handle.net/11511/22077

Collections

Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

H. Güden, “Locations on a line and generalization to the dynamic p-medians,” Ph.D. - Doctoral Program, Middle East Technical University, 2012.