【24h】

Online Bin Covering: Expectations vs. Guarantees

机译:在线垃圾箱覆盖:期望与保证

获取原文

摘要

Bin covering is a dual version of classic bin packing. As usual, bins have size one and items with sizes between zero and one must be packed. However, in bin covering, the objective is to cover as many bins as possible, where a bin is covered if the sizes of items placed in the bin sum up to at least one. We are considering the online version of bin covering. Two classic algorithms for online bin packing that have natural dual versions are Harmonic_k and Next-Fit. Though these two algorithms are quite different in nature, competitive analysis does not distinguish these bin covering algorithms. In order to understand the combinatorial structure of the algorithms better, we turn to other performance measures, namely relative worst order, random order, and max/max analysis, as well as analyses under restricted input assumptions or uniformly distributed input. In this way, our study also supplements the ongoing systematic studies of the relative strengths of various performance measures. We make the case that when guarantees are needed, even under restricted input sequences, the dual Harmonic_k algorithm is preferable. In addition, we establish quite robust theoretical results showing that if items come from a uniform distribution or even if just the ordering of items is uniformly random, then dual Next-Fit is the right choice.
机译:垃圾箱盖是经典垃圾箱包装的双重版本。像往常一样,垃圾箱的尺寸为一,必须包装零到一之间的物品。但是,在垃圾箱覆盖中,目标是覆盖尽可能多的垃圾箱,如果放置在垃圾箱中的物品大小之和至少为一个,则覆盖一个垃圾箱。我们正在考虑垃圾桶覆盖物的在线版本。具有自然双重版本的两种用于在线箱装箱的经典算法是Harmonic_k和Next-Fit。尽管这两种算法本质上是完全不同的,但是竞争分析并未区分这两种bin覆盖算法。为了更好地理解算法的组合结构,我们转向其他性能度量,即相对最差顺序,随机顺序和最大/最大分析,以及在受限输入假设或均匀分布输入下的分析。这样,我们的研究还补充了正在进行的有关各种绩效指标相对优势的系统研究。我们假设当需要保证时,即使在受限的输入序列下,对偶Harmonic_k算法也是可取的。此外,我们建立了非常可靠的理论结果,表明如果项目来自统一的分布,或者即使项目的排序是均匀随机的,那么双重Next-Fit是正确的选择。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号