منابع مشابه
A tight lower bound for job scheduling with cancellation
The Job Scheduling with Cancellation problem is a variation of classical scheduling problems in which jobs can be cancelled while waiting for execution. In this paper we prove a tight lower bound of 5 for the competitive ratio of any deterministic online algorithm for this problem, for the case where all jobs have the same processing time. 2005 Elsevier B.V. All rights reserved.
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We consider the on-line version of the original m-machine scheduling problem: given m machines and n positive real jobs, schedule the n jobs on the m machines so as to minimize the makespan, the completion time of the last job. In the on-line version, as soon as a job arrives, it must be assigned immediately to one of the m machines. We study the competitive ratio of the best algorithm for m-ma...
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In one-machine scheduling, MIP time-indexed formulations are often used to provide very good lower bounds through Lagrangian relaxations. In order to get an improved lower bound, we add valid cuts to a time-indexed formulation and show we still have a Lagrangian relaxation that can be solved as a shortest path in a graph. Two branch-and-bound algorithms are then presented for the earliness-tard...
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ژورنال
عنوان ژورنال: Algorithmica
سال: 2008
ISSN: 0178-4617,1432-0541
DOI: 10.1007/s00453-008-9165-3