Optimal Semi-online Scheduling Algorithms on Two Parallel Identical Machines under a Grade of Service Provision

  • Yong Wu
  • Qifan Yang
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6124)


This paper investigates semi-online scheduling problems on two parallel identical machines under a grade of service (GoS) provision. We consider two different semi-online versions where the optimal offline value of the instance is known in advance or the largest processing time of all jobs is known in advance. Respectively for two semi-online problems, we develop algorithms with competitive ratios of 3/2 and \((\sqrt{5}+1)/2\), which are shown to be optimal.


Scheduling Semi-online Grade of service Two machines Competitive ratio 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  • Yong Wu
    • 1
  • Qifan Yang
    • 2
  1. 1.Department of Fundamental Education, Ningbo Institute of TechnologyZhejiang UniversityNingboPR China
  2. 2.Department of MathematicsZhejiang UniversityHangzhouPR China

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