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The amount of audio-visual information has increased dramatically with the advent of High Speed Internet. Furthermore, technological advances in recent years in the field of information technology, have simplified the use of video data in various fields by the general public. This made it possible to store large collections of video documents into computer systems. To enable efficient use of these collections, it is necessary to develop tools to facilitate access to these documents and handling them. In this paper we propose a method for indexing and retrieval of video sequences in a video database of large dimension, based on a weighting technique to calculate the degree of membership of a concept in a video also a structuring of the data of the audio-visual (context / concept / video). Finally, we decided to create a search system, offering in addition to the usual commands, different types of access to the system, depending on the disability of the person. Indeed, the application consists of a search system but offers access to commands through voice or gestures. Our contribution at the experimental level consists with the implementation of prototype. We integrated the techniques proposed in system to evaluate it contributions in terms of effectiveness and precision., Comment: 6 pages, in French. International conference Human-Machine Interaction and Image IHMIM14, May 2014, Hammamet, Tunisia

Several authors modelled networks ad hoc by oriented or disoriented graphs, whereby the problem of allowance (allocation) of the frequencies at the level of the network was transformed into coloring problem of nodes in the graph. Graph coloring is a tool to characterize the graphs. In our study, we were interested in particular in the coloring of vertex. In this domain, a large number of parameters of coloring were defined. A coloring for which two neighboring summits do not have same color is called proper coloring. We proposed to evaluate two other parameters vertex coloring maximizing the number of colors to use: b-chromatic number and especially the number of Grundy. These studies have focused on two types of graphs, which are the powers graphs and Cartesian sum of graphs. In the first part, we determined borders among Grundy for the Cartesian sum of graphs and finally we proposed algorithms for the coloration of graphs. First of all, we gave some properties and results for simple graphs (stable, chain, cycle, full, star, bipartisan). Secondly, we studied the Cartesian sum of two graphs by giving exact values of the number of Grundy for diverse classes of graphs (sum of a chain and a chain, a chain and a cycle, a cycle and a cycle) then we estimated borders of this parameter for the sum of a complete graph and any other graph. In the second part, we presented the results of the Cartesian sum of several graphs and in the last part; we also gave an algorithm for generating graphs with a given number of Grundy. Thereafter, we studied another parameter namely the partial coloring Grundy. The properties of this parameter are close to those of total Grundy. Finally, we used parameters of coloring total Grundy and partial Grundy to generate algorithms of coloring of graphs. We proposed algorithms of coloring basing on the properties of certain graphs., Comment: in French

A coloring of a graph G = (V,E) is a partition {V1, V2, . . ., Vk} of V into independent sets or color classes. A vertex v Vi is a Grundy vertex if it is adjacent to at least one vertex in each color class Vj . A coloring is a Grundy coloring if every color class contains at least one Grundy vertex, and the Grundy number of a graph is the maximum number of colors in a Grundy coloring. We derive a natural upper bound on this parameter and show that graphs with sufficiently large girth achieve equality in the bound. In particular, this gives a linear time algorithm to determine the Grundy number of a tree.

The problem of the data routing management, it provides a method or a strategy that guarantees at any time the connection between any pair of nodes in the network. This routing method must be able to cope with frequent changes in the topology and also other characteristics of the ad hoc network as bandwidth, the number of links, network resources etc.. We also illustrate the utility of the proposed algorithms: the problem of assignment or frequency allotment in a radio network or mobile phones as in the following way: how to attribute a frequency to every transmitter(issuer) or an unity(unit) of the network, so that two broadcasting stations (issuers) which can interfere have frequencies distant enough from each other ? Thus to affect the wavelengths means finding a coloring of the graph, but because the network is not stable and the topology is dynamic, we need a method which maintains the initial allocation of the frequencies or to look for a new allocation to maintain the stability of the network., Comment: In French

The Grundy number of a graph G is the maximum number k of colors used to color the vertices of G such that the coloring is proper and every vertex x colored with color i, is adjacent to (i - 1) vertices colored with each color j, In this paper we give bounds for the Grundy number of some graphs and Cartesian products of graphs. In particular, we determine an exact value of this parameter for n-dimensional meshes and some n-dimensional toroidal meshes. Finally, we present an algorithm to generate all graphs for a given Grundy number

A Grundy k-coloring of a graph G, is a vertex k-coloring of G such that for each two colors i and j with i < j, every vertex of G colored by j has a neighbor with color i. The Grundy chromatic number (G), is the largest integer k for which there exists a Grundy k-coloring for G. In this note we first give an interpretation of (G) in terms of the total graph of G, when G is the complement of a bipartite graph. Then we prove that determining the Grundy number of the complement of bipartite graphs is an NP-Complete problem

Our work becomes integrated into the general problem of the stability of the network ad hoc. Some, works attacked (affected) this problem. Among these works, we find the modelling of the network ad hoc in the form of a graph. We can resume the problem of coherence of the network ad hoc of a problem of allocation of frequency We study a new class of graphs, the fat-extended P4 graphs, and we give a polynomial time algorithm to calculate the Grundy number of the graphs in this class. This result implies that the Grundy number can be found in polynomial time for many graphs, Comment: 5 pages

Our work becomes integrated into the general problem of the stability of the network ad hoc. Some, works attacked this problem. Among these works, we find the modelling of the network ad hoc in the form of a graph. Thus the problem of stability of the network ad hoc which corresponds to a problem of allocation of frequency amounts to a problem of allocation of colors in the vertex of graph. we present use a parameter of coloring the number of Grundy. The Grundy number of a graph G, denoted by (G), is the largest k such that G has a greedy k-coloring, that is a coloring with colours obtained by applying the greedy algorithm according to some ordering of the vertices of G. In this paper, we study the Grundy number of the lexicographic, Cartesian and direct products of two graphs in terms of the Grundy numbers of these graphs., Comment: 13 pages, International Journal of Next-Generation Networks (IJNGN),December 2013

This paper presents a new progressive compression method for triangular meshes. This method, in fact, is based on a schema of irregular multi-resolution analysis and is centered on the optimization of the rate-distortion trade-off. The quantization precision is adapted to each vertex during the encoding / decoding process to optimize the rate-distortion compromise. The Optimization of the treated mesh geometry improves the approximation quality and the compression ratio at each level of resolution. The experimental results show that the proposed algorithm gives competitive results compared to the previous works dealing with the rate-distortion compromise., Comment: 8 pages, 5 figures