Bilel Derbel

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Given a palette $P$ of at most $\xi$ colors, and a parameter $d$, a $(d,\xi)$-coloring of a graph is an assignment of a color from the palette $P$ to every node in the graph such that any two nodes at distance at most $d$ have different colors. We prove that for every $n$-node unit disk graph with maximum degree $\Delta$, there exists a distributed(More)
The paper presents a deterministic distributed algorithm that, given k &#8805; 1, constructs in k rounds a (2k-1,0)-spanner of O(k n<sup>1+1/k</sup>) edges for every n-node unweighted graph. (If n is not available to the nodes, then our algorithm executes in 3k-2 rounds, and still returns a (2k-1,0)-spanner with O(k n<sup>1+1/k</sup>) edges.) Previous(More)
We present new efficient deterministic and randomized distributed algorithms for decomposing a graph with n nodes into a disjoint set of connected clusters with radius at most k−1 and having O(n 1+1/k ) intercluster edges. We show how to implement our algorithms in the distributed $\mathcal{CONGEST}$ model of computation, i.e., limited message size, which(More)
The paper deals with radio network distributed algorithms where nodes are not aware of their one hop neighborhood. Given an n-node graph modeling a multihop network of radio devices, we give a O(log n) time distributed algorithm that computes w.h.p., a constant approximation value of the degree of each node. We also provide a O(∆ log n+ log n) time(More)
The paper presents a deterministic distributed algorithm that given an n node unweighted graph constructs an O(n) edge 3spanner for it in O(log n) time. This algorithm is then extended into a deterministic algorithm for computing an O(k n) edge O(k)-spanner in 2 logk−1 n time for every integer parameter k 1. This establishes that the problem of the(More)
In this paper, we build upon the previous efforts to enhance the search ability of Moead (a decomposition-based algorithm), by investigating the idea of evolving the whole population simultaneously at once. We thereby propose new alternative selection and replacement strategies that can be combined in different ways within a generic and problem-independent(More)
Wireless sensor networks (WSN) have received significant attention over the last few years as they afford a growing number of applications in various fields. At the same time, these networks provide numerous challenges due to their constraints, primarily related to energy scarcity. To overcome energy waste caused by collisions and contention based(More)
Recently, there has been a renewed interest in decomposition-based approaches for evolutionary multiobjective optimization. However, the impact of the choice of the underlying scalarizing function(s) is still far from being well understood. In this paper, we investigate the behavior of different scalarizing functions and their parameters. We thereby(More)
This paper presents efficient deterministic and randomized distributed algorithms for decomposing a graph with n nodes into a disjoint set of connected clusters with small radius and few intercluster edges. Our algorithms can be easily implemented in the distributed CONGEST model of computation i.e., limited message size, improving the time complexity of(More)