arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1408.4490cs.DS
收藏

随机准时到达问题的易处理寻路算法

Tractable Pathfinding for the Stochastic On-Time Arrival Problem

Mehrdad Niknami, Samitha Samaranayake

摘要:

我们提出了一种新的和更有效的技术来计算的路线,最大限度地提高概率的随机网络,也被称为基于路径的随机准时到达(SOTA)问题。我们的主要贡献是一个寻路算法,它使用的解决方案,以基于政策的SOTA问题-这是伪多项式时间复杂度的时间预算的旅程-作为搜索启发式的最佳path. In特别是,我们表明,这种启发式可以是非常有效的,在实践中,有效地使之成为可能,以解决基于路径的SOTA问题,尽快为基于政策的SOTA问题。我们的第二个贡献是基于策略的预处理的SOTA问题的路径为基础的预处理的扩展。在这个过程中,我们还介绍了弧势,一个更有效的推广随机弧旗,可用于基于策略和路径的SOTA。在开发了路径查找和预处理算法之后,我们在两个不同的现实网络上评估了它们的性能。据我们所知,这些技术提供了最有效的计算策略的路径为基础的SOTA问题的一般概率分布,无论有和没有预处理。

英文摘要:

We present a new and more efficient technique for computing the route that maximizes the probability of on-time arrival in stochastic networks, also known as the path-based stochastic on-time arrival (SOTA) problem. Our primary contribution is a pathfinding algorithm that uses the solution to the policy-based SOTA problem---which is of pseudo-polynomial-time complexity in the time budget of the journey---as a search heuristic for the optimal path. In particular, we show that this heuristic can be exceptionally efficient in practice, effectively making it possible to solve the path-based SOTA problem as quickly as the policy-based SOTA problem. Our secondary contribution is the extension of policy-based preprocessing to path-based preprocessing for the SOTA problem. In the process, we also introduce Arc-Potentials, a more efficient generalization of Stochastic Arc-Flags that can be used for both policy- and path-based SOTA. After developing the pathfinding and preprocessing algorithms, we evaluate their performance on two different real-world networks. To the best of our knowledge, these techniques provide the most efficient computation strategy for the path-based SOTA problem for general probability distributions, both with and without preprocessing.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑