Half-integrality of node-capacitated multiflows and tree-shaped facility locations on trees
نویسندگان
چکیده
منابع مشابه
Half-integrality of node-capacitated multiflows and tree-shaped facility locations on trees
In this paper, we establish a novel duality relationship between node-capacitated multiflows and tree-shaped facility locations. We prove that the maximum value of a tree-distance-weighted maximum node-capacitated multiflow problem is equal to the minimum value of the problem of locating subtrees in a tree, and the maximum is attained by a half-integral multiflow. Utilizing this duality, we sho...
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We consider an undirected graph G = (VG,EG) with a set T ⊆ VG of terminals, and with nonnegative integer capacities c(v) and costs a(v) of nodes v ∈ VG. A path in G is a T -path if its ends are distinct terminals. By a multiflow we mean a function F assigning to each T -path P a nonnegative rational weight F(P ), and a multiflow is called feasible if the sum of weights of T -paths through each ...
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ژورنال
عنوان ژورنال: Mathematical Programming
سال: 2011
ISSN: 0025-5610,1436-4646
DOI: 10.1007/s10107-011-0506-7