arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1107.1012cs.CGcs.DS
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覆盖圆形区域的最优点移动

Optimal Point Movement for Covering Circular Regions

Danny Z. Chen, Xuehou Tan, Haitao Wang, Gangshan Wu

摘要:

给定平面上圆形区域$C$中的$n$点,研究了将$n$点移动到其边界形成正则$n$ -边形,使得点所经过的欧氏距离的最大值(min-max)或和(min-sum)最小化的问题.这些问题具有应用,例如,在移动传感器屏障覆盖的无线传感器网络。最小-最大问题还有两个版本:决策版本和优化版本。对于最小-最大问题,我们提出了一个$O(n\log^2 n)$时间算法的决策版本和$O(n\log^3 n)$时间算法的优化版本。对于这两个问题版本,以前最好的算法分别需要$O(n^{3.5})$时间和$O(n^{3.5}\log n)$时间。对于最小和问题,我们表明,一个特殊的情况下,所有的点最初躺在边界上的圆形区域可以解决在$O(n^2)$时间,提高以前的$O(n^4)$时间解决方案。对于一般的最小和问题,我们提出了一个3-近似$O(n^2)$时间算法,改进了以前的$(1+π)$ -近似$O(n^2)$时间算法.我们的技术的一个副产品是一个算法,用于动态保持最大匹配的圆形凸二分图,我们的算法可以处理每个顶点插入或删除的图形在$O(\log^2 n)$时间。这个结果本身就很有趣。

英文摘要:

Given $n$ points in a circular region $C$ in the plane, we study the problems of moving the $n$ points to its boundary to form a regular $n$-gon such that the maximum (min-max) or the sum (min-sum) of the Euclidean distances traveled by the points is minimized. The problems have applications, e.g., in mobile sensor barrier coverage of wireless sensor networks. The min-max problem further has two versions: the decision version and optimization version. For the min-max problem, we present an $O(n\log^2 n)$ time algorithm for the decision version and an $O(n\log^3 n)$ time algorithm for the optimization version. The previously best algorithms for the two problem versions take $O(n^{3.5})$ time and $O(n^{3.5}\log n)$ time, respectively. For the min-sum problem, we show that a special case with all points initially lying on the boundary of the circular region can be solved in $O(n^2)$ time, improving a previous $O(n^4)$ time solution. For the general min-sum problem, we present a 3-approximation $O(n^2)$ time algorithm, improving the previous $(1+π)$-approximation $O(n^2)$ time algorithm. A by-product of our techniques is an algorithm for dynamically maintaining the maximum matching of a circular convex bipartite graph; our algorithm can handle each vertex insertion or deletion on the graph in $O(\log^2 n)$ time. This result is interesting in its own right.

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。

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