A PTAS for Minimizing the Total Weighted Completion Time on Identical Parallel Machines
نویسندگان
چکیده
We consider the problem of scheduling a set of n jobs on m identical parallel machines so as to minimize the weighted sum of job completion times. This problem is NP-hard in the strong sense. The best approximation result known so far was a 2 (1 + √ 2)-approximation algorithm that has been derived by Kawaguchi and Kyan back in 1986. The contribution of this paper is a polynomial time approximation scheme for this setting, which settles a problem that was open for a long time. Moreover, our result constitutes the =rst known approximation scheme for a strongly NP-hard scheduling problem with minsum objective.
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We consider the well known problem of scheduling jobs with release dates to minimize their average weighted completion time. When multiple machines are available, the machine environment may range from identical machines (the processing time required by a job is invariant across the machines) at one end of the spectrum to unrelated machines (the processing time required by a job on each machine...
متن کاملA PTAS for Minimizing Weighted Completion Time on Uniformly Related Machines
We consider the well known problem of scheduling jobs with release dates to minimize their average weighted completion time. When multiple machines are available, the machine environment may range from identical machines (the processing time required by a job is invariant across the machines) at one end of the spectrum to unrelated machines (the processing time required by a job on each machine...
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عنوان ژورنال:
- Math. Oper. Res.
دوره 25 شماره
صفحات -
تاریخ انتشار 2000