For most scheduling problems the set of machines is fixed initially and remains unchanged for the duration of the problem. We consider two basic online scheduling problems with the modification that initially the algorithm possesses no machines, but that at any point additional machines may be purchased. Upper and lower bounds on the competitive ratio are shown for both problems.


Schedule Problem Time Model Competitive Ratio Online Algorithm Optimal Cost 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1999

Authors and Affiliations

  • Csanád Imreh
    • 1
    • 2
  • John Noga
    • 3
  1. 1.Department of InformaticsJózsef Attila UniversitySzegedHungary
  2. 2.Stochastic Research Group, Hungarian Academy of SciencesTechnical UniversityBudapestHungary
  3. 3.Mathematics DepartmentTechnical University GrazGrazAustria

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