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Minimum Weighted Completion Time

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Encyclopedia of Algorithms

Years and Authors of Summarized Original Work

  • 1999; Afrati et al.

Problem Definition

The minimum weighted completion time problem involves (i) a set J of n jobs, a positive weight w j for each job j ∈ J, and a release date r j before which it cannot be scheduled; (ii) a set of m machines, each of which can process at most one job at any time; and (iii) an arbitrary set of positive values {pi, j}, where pi, j denotes the time to process job j on machine i. A schedule involves assigning jobs to machines and choosing an order in which they are processed. Let C j denote the completion time of job j for a given schedule. The weighted completion time of a schedule is defined as ∑j ∈ Jw j C j , and the goal is to compute a schedule that has the minimum weighted completion time.

In the scheduling notation introduced by Graham et al. [8], a scheduling problem is denoted by a 3-tuple α | β | γ, where α denotes the machine environment, β denotes the additional constraints on jobs, and γdenotes...

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Acknowledgements

The Research of V.S. Anil Kumar and M.V. Marathe was supported in part by NSF Award CNS-0626964. A. Srinivasan’s research was supported in part by NSF Award CNS-0626636.

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Correspondence to V. S. Anil Kumar .

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Kumar, V.S.A., Marathe, M., Parthasarathy, S., Srinivasan, A. (2016). Minimum Weighted Completion Time. In: Kao, MY. (eds) Encyclopedia of Algorithms. Springer, New York, NY. https://doi.org/10.1007/978-1-4939-2864-4_240

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