论文标题

用于查找最佳路由集的有效算法

An Efficient Algorithm for Finding Sets of Optimal Routes

论文作者

Zoref, Ido, Orda, Ariel

论文摘要

在几种重要的路由环境中,需要确定一组路由,每种路线都优化了不同的标准。例如,在车辆路线的背景下,一条路线将最大程度地减少行驶的总距离,而其他路线也将考虑总旅行时间或总成本或组合的总成本。通常,通过在网络边缘上的不同权重方面找到最佳路线,可以获得提供这样一组不同的路线。可以通过连续执行标准最短路径算法来简单地实现这一点。但是,在大量重量集的情况下,这可能需要过多的这种算法执行,从而产生了极大的运行时间。 我们表明,通常,不同的边缘权重反映了某些“原始”性能指标(例如延迟,成本)的不同组合。在这种情况下,同一边缘的不同权重之间存在固有的依赖性。这很可能会导致最短路线之间的相似之处,每种路线相对于一组特定的权重。在这项研究中,我们旨在利用这种相似性,以提高解决方案方案的性能。 具体而言,我们考虑了通过某些(``RAW'')边缘性能指标的不同线性组合获得的边缘权重。我们建立并验证一种新型算法,该算法有效地计算每组边缘权重的最短路径。我们证明,在合理的假设下,该算法显着优于标准方法。与标准方法类似,算法迭代搜索路线,每组边缘重量为一组;但是,它没有通过在迭代中巧妙地共享信息来减少平均运行时间,而不是独立执行每次迭代。

In several important routing contexts it is required to identify a set of routes, each of which optimizes a different criterion. For instance, in the context of vehicle routing, one route would minimize the total distance traveled, while other routes would also consider the total travel time or the total incurred cost, or combinations thereof. In general, providing such a set of diverse routes is obtained by finding optimal routes with respect to different sets of weights on the network edges. This can be simply achieved by consecutively executing a standard shortest path algorithm. However, in the case of a large number of weight sets, this may require an excessively large number of executions of such an algorithm, thus incurring a prohibitively large running time. We indicate that, quite often, the different edge weights reflect different combinations of some "raw" performance metrics (e.g., delay, cost). In such cases, there is an inherent dependency among the different weights of the same edge. This may well result in some similarity among the shortest routes, each of which being optimal with respect to a specific set of weights. In this study, we aim to exploit such similarity in order to improve the performance of the solution scheme. Specifically, we contemplate edge weights that are obtained through different linear combinations of some (``raw'') edge performance metrics. We establish and validate a novel algorithm that efficiently computes a shortest path for each set of edge weights. We demonstrate that, under reasonable assumptions, the algorithm significantly outperforms the standard approach. Similarly to the standard approach, the algorithm iteratively searches for routes, one per set of edge weights; however, instead of executing each iteration independently, it reduces the average running time by skillfully sharing information among the iterations.

扫码加入交流群

加入微信交流群

微信交流群二维码

扫码加入学术交流群,获取更多资源