Cyclic arc-connectivity in a Cartesian product digraph
โ Scribed by Zhao Zhang; Yufang Zhu
- Publisher
- Elsevier Science
- Year
- 2010
- Tongue
- English
- Weight
- 319 KB
- Volume
- 23
- Category
- Article
- ISSN
- 0893-9659
No coin nor oath required. For personal study only.
โฆ Synopsis
A digraph D is cycle separable if it contains two vertex disjoint directed cycles. For a cycle separating digraph D, an arc set S is a cycle separating arc-cut if D-S has at least two strong components containing directed cycles. The cyclic arc-connectivity ฮป c (D) is the minimum cardinality of all cycle separating arc-cuts. In this work, we study ฮป c (D) for the Cartesian product digraph D = D 1 ร D 2 . We give a necessary and sufficient condition for D 1 ร D 2 to be cycle separable, and show that ฮป c (D 1 ร D 2 ) = 0 if D 1 ร D 2 is cycle separable but not strongly connected. For the case where D = D 1 ร D 2 is strongly connected, we give an upper bound and a lower bound for ฮป c (D). In particular, it can be determined that ฮป
min{n 1 , n 2 , . . . , n k }, where C n i is a directed cycle of length n i .
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