An improved lower bound for rank four scheduling

被引:8
作者
Chen, Lin [1 ]
Ye, Deshi [1 ]
Zhang, Guochuan [1 ]
机构
[1] Zhejiang Univ, Coll Comp Sci, Hangzhou, Zhejiang, Peoples R China
关键词
Complexity; APX-hardness; Scheduling; APPROXIMATION;
D O I
10.1016/j.orl.2014.06.003
中图分类号
C93 [管理学]; O22 [运筹学];
学科分类号
070105 ; 12 ; 1201 ; 1202 ; 120202 ;
摘要
We consider the classical minimum makespan scheduling problem, where the processing time of job j on machine i is p(ij), and the matrix P = (p(ij))(mxn) is of a low rank. It is proved in Bhaskara et al. (2013) that rank 7 scheduling is NP-hard to approximate to a factor of 3/2 - epsilon, and rank 4 scheduling is APX-hard (a factor of 1.03 - epsilon). We improve this result by showing that rank 4 scheduling is already NP-hard to approximate within a factor of 3/2 - epsilon. (C) 2014 Elsevier B.V. All rights reserved.
引用
收藏
页码:348 / 350
页数:3
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