The Steiner ratio of the clustered Steiner tree problem is three
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چکیده
The Clustered Steiner tree problem is a variant of Steiner minimum tree problem. The required vertices are partitioned into clusters, and the subtrees spanning different clusters must be disjoint in a feasible clustered tree. In this paper we show that the Steiner ratio of the cluster Steiner tree problem is three, where the Steiner ratio is defined as the largest possible ratio of the minimal cost without using any Steiner vertex to the optimal cost.
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تاریخ انتشار 2014