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Journal of Combinatorial Optimization

, Volume 11, Issue 2, pp 177–187 | Cite as

A dynamic programming approach of finding an optimal broadcast schedule in minimizing total flow time

  • Wun-Tat Chan
  • Francis Y. L. Chin
  • Yong Zhang
  • Hong Zhu
  • Hong Shen
  • Prudence W. H. Wong
Article
  • 79 Downloads

Abstract

We study the problem of (off-line) broadcast scheduling in minimizing total flow time and propose a dynamic programming approach to compute an optimal broadcast schedule. Suppose the broadcast server has k pages and the last page request arrives at time n. The optimal schedule can be computed in O(k3(n+k)k−1) time for the case that the server has a single broadcast channel. For m channels case, i.e., the server can broadcast m different pages at a time where m < k, the optimal schedule can be computed in O(nkm) time when k and m are constants. Note that this broadcast scheduling problem is NP-hard when k is a variable and will take O(nkm+1) time when k is fixed and m ≥ 1 with the straightforward implementation of the dynamic programming approach.

Keywords

Broadcast scheduling flow time minimization dynamic programming 

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Copyright information

© Springer Science + Business Media, LLC 2006

Authors and Affiliations

  • Wun-Tat Chan
    • 1
  • Francis Y. L. Chin
    • 1
  • Yong Zhang
    • 1
  • Hong Zhu
    • 2
  • Hong Shen
    • 3
  • Prudence W. H. Wong
    • 4
  1. 1.Department of Computer ScienceUniversity of Hong KongHong Kong
  2. 2.Department of Computer Science and EngineeringFudan UniversityChina
  3. 3.Graduate School of Information ScienceJapan Advanced Institute of Science and TechnologyJapan
  4. 4.Department of Computer ScienceUniversity of LiverpoolUK

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