As an emerging coverage problem in wireless sensor networks, sweep coverage which introducing mobile sensors to cover points of interest within certain time interval can satisfy monitoring request in some particular application scenarios with less number of nodes than the conventional static coverage approach. In this work, aiming to support dynamical POI coverage and data delivery simultaneous...

Given a text T and a pattern P over alphabet Σ, the classic exact matching problem searches for all occurrences of pattern P in text T . Unlike exact matching problem, order-preserving pattern matching (OPPM) considers the relative order of elements, rather than their real values. In this paper, we propose an efficient algorithm for OPPM problem using the “duel-and-sweep” paradigm. Our algorith...

We show how to implement eecient copying garbage collection for Prolog. We measure the eeciency of the collector compared to a standard mark-sweep algorithm on several programs. We then show how to acco-modate generational garbage collection and Prolog primitives that make the implementation more diicult. The resulting algorithms are simpler and more eecient than the standard mark-sweep method ...

For applying the sweep-line method, a state space reduction technique, it is necessary to provide an automatic calculation of a progress measure. In [1], such a calculation has been proposed for Petri nets. The approach presented there may lead to suboptimal results, therefore the author suggested possible optimizations. In this paper, we check whether the proposed optimization goals indeed lea...

We present data structures for maintaining the relative convex hull of a set of points (sites) in the presence of pairwise non-crossing line segments (barriers) that subdivide a bounding box into simply connected faces. Our data structures have O((n + m) log n) size for n sites and m barriers. They support O(m) barrier insertions and O(n) site deletions in O((m + n) polylog (mn)) total time, an...

Sweep method is one of the most robust techniques to generate hexahedral meshes in extrusion volumes. One of the main issues to be dealt by any sweep algorithm is the projection of a source surface mesh onto the target surface. This paper presents a new algorithm to map a given mesh over the source surface onto the target surface. This projection is carried out by means of a least-squares appro...

This report outlines the design and implementation of an algorithm to sweep a 3 dimensional tetrahedral complex in a particular direction. The problem is considered in its most generality, that is, the tetrahedral complex can be concave and have holes inside it which can themselves be concave. This algorithm can be used to e ciently perform ray-tracing of 3-D objects. The main idea in the algor...

Vehicle Routing Problem (VRP) has become an integral part in logistic operations which determines optimal routes for several vehicles to serve customers. The basic version of VRP is Capacitated VRP (CVRP) which considers equal capacities for all vehicles. The objective of CVRP is to minimize the total traveling distance of all vehicles to serve all the customers. Various methods are used to sol...

This paper presents an improved scheme to compensate nonlinear phase path contamination when the backscattered signal propagates through the ionosphere in high-frequency skywave radar systems. The ionospheric variation often causes the spread of the ocean clutter spectrum in the frequency domain. The energy of the first-order component of ocean clutter dominates in Doppler spectrum, and thus it...