Intrusion detection, area coverage and border surveillance are important applications of wireless sensor networks today. They can be (and are being) used to monitor large unprotected areas so as to detect intruders as they cross a border or as they penetrate a protected area. We consider the problem of how to optimally move mobile sensors to the fence (perimeter) of a region delimited by a simple polygon in order to detect intruders from either entering its interior or exiting from it. We discuss several related issues and problems, propose two models, provide algorithms and analyze their optimal mobility behavior.

We consider clustering problems under two different optimization criteria. One is to minimize the maximum intracluster distance (diameter), and the other is to maximize the rninimuJn intercluster distance. In particular, we present an algorithm which partitions a set S of n points in the plane into two subsets so that their larger diameter is minimized in time O(nlogn) and space O(n). Another algorithm with the same bounds computes a k-partition of S for any k so that the minimum intercluster distance is maximized. In both instances it is first shown that an optimal parition is determined by either a maximum or minimum spanning tree of S.

true2016-03-16T16:38:26

We present a novel approach to finding the k-sink on dynamic path networks with general edge capacities. Our first algorithm runs in O(n log n + k 2 log 4 n) time, where n is the number of vertices on the given path, and our second algorithm runs in O(n log 3 n) time. Together, they improve upon the previously most efficient O(kn log 2 n) time algorithm due to Arumugam et al. [1] for all values of k. In the case where all the edges have the same capacity, we again present two algorithms that run in O(n + k 2 log 2 n) time and O(n log n) time, respectively, and they together improve upon the previously best O(kn) time algorithm due to Higashikawa et al. [10] for all values of k. ACM Subject Classification F.2.2

No abstract

No abstract

No abstract

No abstract