Non-approximability of precedence-constrained sequencing to minimize setups
نویسنده
چکیده
It is a basic scheduling problem to sequence a set of precedence-constrained tasks to minimize the number of setups, where the tasks are partitioned into classes that require the same setup. We prove a conjecture in (Ph.D. Thesis, School of ISyE, Georgia Institute of Technology, August 1986; Oper. Res. 39 (1991) 1012) that no polynomial-time algorithm for this problem has constant worst-case performance ratio unless P = NP. A very simple algorithm has performance ratio √ n. ? 2003 Elsevier B.V. All rights reserved.
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عنوان ژورنال:
- Discrete Applied Mathematics
دوره 134 شماره
صفحات -
تاریخ انتشار 2004