0000000000406518
AUTHOR
Olivier Togni
showing 5 related works from this author
A Note on Radio Antipodal Colouring of Paths
2005
International audience; The radio antipodal number of a graph G is the smallest integer c such that there exists an assignment f : V (G) -> {1, 2, . . . , c} satisfying |f(u) − f(v)| >= D − d(u, v) for every two distinct vertices u and v of G, where D is the diameter of G. In this note we determine the exact value of the antipodal number of the path, thus answering the conjecture given in [G. Chartrand, D. Erwin, and P. Zhang. Radio antipodal colorings of graphs, Math. Bohem. 127(1):57-69, 2002]. We also show the connections between this colouring and radio labelings.
Vertex Distinguishing Edge- and Total-Colorings of Cartesian and other Product Graphs
2012
International audience; This paper studies edge- and total-colorings of graphs in which (all or only adjacent) vertices are distinguished by their sets of colors. We provide bounds for the minimum number of colors needed for such colorings for the Cartesian product of graphs along with exact results for generalized hypercubes. We also present general bounds for the direct, strong and lexicographic products.
Integrated Fuzzy Solution for Network Selection using MIH in Heterogeneous Environment
2013
ISSN: 1942-2644; International audience; Seamless handover between networks in heterogeneous environment is essential to guarantee end-to- end QoS for mobile users. A key requirement is the ability to select seamlessly the next best network. Currently, the implementation of the selection algorithm of the IEEE 802.21 standard by National Institute of Standards and Technology considers only the signal strength as a parameter to select the best destination network. In this paper, we improve the implementation of the existing selection algorithm by proposing an integrated solution to select the best destination network. Our proposed solution consists of proposing a Multi Criteria Selection Algo…
Smart Network Selection and Packet Loss Improvement during Handover in Heterogeneous Environment
2013
BEST PAPER AWARD; International audience; Seamless Handover between networks in heterogeneous environment is essential to guarantee end-to-end QoS for mobile users. A key requirement is the ability to select the next best network. Currently, the implementation of the IEEE 802.21 standard by National Institute of Standards and Technology (NIST) considers only the signal strength as a parameter to determine the best network. In this paper, we propose including additional parameters such as available bandwidth, mobile node speed and type of network during selecting a new network to improve the QoS for mobile user's application. The results of the experiments that we performed using Network Sim…
Arbres couvrants presque disjoints
2015
International audience; Dans un réseau, la recherche de plusieurs arbres couvrants avec des propriétés intéressantes a amené à l'introduc-tion de plusieurs notions : les arbres couvrants arête-disjoints, les arbres indépendants enracinés en un sommet et les arbres complètement indépendants. Afin de généraliser ces notions, nous introduisons la notion d'arbres couvrants (i, j)-disjoints, où i et j sont respectivement le nombre maximum de noeuds internes et d'arêtes communs aux arbres couvrants. Nous montrons que déterminer s'il existe deux arbres couvrants (i, j)-disjoints dans un graphe G est un problème NP-complet pour i et j quelconques, et nous déterminons les valeurs minimales de i et j…