COCOON 2000: Computing and Combinatorics pp 232-241 | Cite as

Ordinal On-Line Scheduling on Two Uniform Machines

  • Zhiyi Tan
  • Yong He
Conference paper
First Online:
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1858)

Abstract

We investigate the ordinal on-line scheduling problem on two uniform machines. We present a comprehensive lower bound of any ordinal algorithm, which constitutes a piecewise function of machine speed ratio s ≥ 1. We further propose an algorithm whose competitive ratio matches the lower bound for most of s ∈ (1,∞). The total length of the intervals of s where the competitive ratio does not match the lower bound is less than 0:7784 and the biggest gap never exceeds 0:0521.

Keywords

Competitive Ratio Online Algorithm Speed Ratio List Schedule Online Schedule 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
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Copyright information

© Springer-Verlag Berlin Heidelberg 2000

Authors and Affiliations

  • Zhiyi Tan
    • 1
  • Yong He
    • 1
  1. 1.Department of MathematicsZhejiang UniversityHangzhouP.R. China

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