Approximate min-max theorems of Steiner rooted-orientations of hypergraphs

Király, Tamás and Lau, Lap Chi (2006) Approximate min-max theorems of Steiner rooted-orientations of hypergraphs. In: 47th Annual IEEE Symposium on Foundations of Computer Science. ANNUAL IEEE SYMPOSIUM ON FOUNDATIONS OF COMPUTER SCIENCE . IEEE Computer Society, Los Alamitos, pp. 283-292. ISBN 0-7695-2720-5


Download (410kB) | Preview


Given an undirected hypergraph and a subset of vertices S ⊆ V with a specified root vertex r ∈ S, the STEINER ROOTED-ORIENTATION problem is to find an orientation of all the hyperedges so that in the resulting directed hypergraph the "connectivity" from the root r to the vertices in S is maximized. This is motivated by a multicasting problem in undirected networks as well as a generalization of some classical problems in graph theory. The main results of this paper are the following approximate min-max relations: • Given an undirected hypergraph H, if S is 2k-hyperedge-connected in H, then H has a Steiner rooted k-hyperarc-connected orientation. • Given an undirected graph G, if S is 2k-element-connected in G, then G has a Steiner rooted k-element-connected orientation. Both results are tight in terms of the connectivity bounds. These also give polynomial time constant factor approximation algorithms for both problems. The proofs are based on submodular techniques, and a graph decomposition technique used in the STEINER TREE PACKING problem. Some complementary hardness results are presented at the end. © 2006 IEEE.

Item Type: Book Section
Uncontrolled Keywords: Theorem proving; Set theory; Problem solving; Graph theory; Computational complexity; Approximation algorithms; Undirected hypergraph; Steiner rooted-orientation problem; GRAPHS; VERTICES
Subjects: Q Science / természettudomány > QA Mathematics / matematika
Depositing User: MTMT SWORD
Date Deposited: 16 Dec 2014 13:35
Last Modified: 16 Dec 2014 13:35

Actions (login required)

Edit Item Edit Item