Lagrangean relaxation with clusters for point-feature cartographic label placement problems
نویسندگان
چکیده
This paper presents two new mathematical formulations for the Point-Feature Cartographic Label Placement Problem (PFCLP ) and a new Lagrangean relaxation with clusters (LagClus) to provide bounds to these formulations. The PFCLP can be represented by a conflict graph and the relaxation divides the graph in small sub problems (clusters) that are easily solved. The edges connecting clusters are relaxed in a Lagrangean way and a subgradient algorithm improves the bounds. The LagClus was successfully applied to a set of instances up to 1000 points providing the best results of those reported in the literature.
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ورودعنوان ژورنال:
- Computers & OR
دوره 35 شماره
صفحات -
تاریخ انتشار 2008