arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 2202.01757cs.CG
收藏

$k$-发射器守望者路线

$k$-Transmitter Watchman Routes

Bengt J. Nilsson, Christiane Schmidt

AI总结:

研究$k$-发射器守望者路线问题,证明在简单多边形中求最短路线为NP完全且难以近似,并给出给定起点时的多对数近似算法。

摘要:

我们考虑$k$-发射器守望者的守望者路线问题:站在多边形$P$中的点$p$处,守望者可以看到$q\in P$,如果线段$\overline{pq}$与$P$的边界相交至多$k$次——即$q$对$p$是$k$-可见的。沿着$k$-发射器守望者路线行进时,$P$中的所有点或离散点集$S\subset P$必须对守望者$k$-可见。我们的目标是使$k$-发射器守望者路线的长度最小化。我们证明,即使在简单多边形中,对于离散点集$S\subset P$的最短$k$-发射器守望者路线问题是NP完全的,并且(除非P=NP)无法在对数因子内近似,无论是否给定起点。此外,我们针对给定起点和$S\subset P$的$k$-发射器守望者路线问题提出了一个多对数近似,近似比为$O(\log^2(|S|\cdot n) \log\log (|S|\cdot n) \log(|S|+1))$(其中$|P|=n$)。

英文摘要:

We consider the watchman route problem for a $k$-transmitter watchman: standing at point $p$ in a polygon $P$, the watchman can see $q\in P$ if $\overline{pq}$ intersects $P$'s boundary at most $k$ times -- $q$ is $k$-visible to $p$. Traveling along the $k$-transmitter watchman route, either all points in $P$ or a discrete set of points $S\subset P$ must be $k$-visible to the watchman. We aim for minimizing the length of the $k$-transmitter watchman route. We show that even in simple polygons the shortest $k$-transmitter watchman route problem for a discrete set of points $S\subset P$ is NP-complete and cannot be approximated to within a logarithmic factor (unless P=NP), both with and without a given starting point. Moreover, we present a polylogarithmic approximation for the $k$-transmitter watchman route problem for a given starting point and $S\subset P$ with approximation ratio $O(\log^2(|S|\cdot n) \log\log (|S|\cdot n) \log(|S|+1))$ (with $|P|=n$).

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。

↑