In the first we introduce basic notions of scheduling problems, competitive analysis and approximation algorithm, summarize semi online models and their results which appear in recent years.
本文首先简要介绍了排序问题、竞争比分析和近似算法等基本概念，总结了近年来出现的各个半在线模型及其有关结果。
This paper studies semi online parallel machine scheduling problems.
本文主要考虑平行机半在线排序问题。
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