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Multicast connections are efficient for applications such as telemedicine, distributed computing, and distance learning in an all-optical WDM network. To re-optimize the use of network resources such as wavelength channels in the all-optical WDM network, the network operator uses the reconfiguration operation, which affects certain multicast connections. Note that during reconfiguration, a pair of light-trees contributes to the identification of each multicast connection. A light-tree is a path used to transmit an optical flow of a multicast connection. However, the interruption of the flow during reconfiguration of a pair of light-trees may result in the operator having to pay a penalty fee. Thus, the problem studied here is to reconfigure a set of light-trees pairs while minimizing penalty fees. Existing methods focus on reconfiguration that aims to minimize flow interruptions. However, minimizing flow interruptions does not induce the minimum total penalty fees because the penalty fees due to flow interruptions are not always the same for all multicast connections. Therefore, we propose a method that considers the fact that the penalty fees are not the same for all multicast connections to minimize the penalty fees during reconfiguration. The experimental results confirmed the effectiveness of the proposed method.

International audience; Network reconfiguration is an important mechanism for network operators to optimize network performance and optical flow transfer. It concerns unicast and multicast connections. Multicast connections are required to meet the bandwidth requirements of multicast applications, such as Internet Protocol-based TeleVision (IPTV), distance learning, and telemedicine. In optical networks, a multicast connection is made possible by the creation of an optical tree-shaped path called a light-tree. The problem of light-tree pair reconfiguration is addressed in this study. Given an initial light-tree used to transfer an optical flow and a final light-tree that is computed by the network operator to optimize network performance, the goal is to migrate the optical flow from the initial light-tree to the final light-tree without flow interruption. Flow interruption is not desirable for network operators because it forces them to pay financial penalties to their customers. To solve this problem, existing methods use a branch approach that is inefficient if some network nodes do not have wavelength conversion capability. Therefore, we proposed in this study a sub-tree-based method. This approach selects and configures sub-tree pairs from the light-tree pair (initial light-tree, final light-tree) to be reconfigured. Then, we produce a sequence of configurations. The performance study confirms that our method is efficient in solving the problem of light-tree pair reconfiguration because our method does not cause flow interruption.

The image fusion technique is widely used in remote sensing. Its purpose is to provide comprehensive information without arte facts by combining the partial information from different source images. In this study, we propose a new model of images fusion with very high spatial resolution. We use the separation capacities of the Morphological Component Analysis (MCA) to extract the smooth and texture components of our images. These morphological components are then fused separately using the decomposition in the Laplacian pyramids for the smooth part and bivariate Hahn polynomials for texture part. Finally the image fusion is obtained through linear combination of merged smooth and texture components. The experiments carried out on IKONOS, LANDSAT and Quick Bird remote sensing images show the good performances of our method which has been compared to conventional methods. The performances obtained in our experiments are characterized by a small global metric such as ERGAS equals to 3.88 for IKONOS image and 3.65 for QuickBird image compared to 8.70 for IKONOS image and 6.97 for QuickBird for conventional HIS algorithms. We also have a mean loss of 15% for spectral information com pare to those of the conventional methods which revolve around 25%. The degradation of spatial information in order of 17% in contrast to conventional HIS algorithms which oscillate around 21%.

The work on predicting learner performance allows researchers through machine learning methods to participate in the improvement of e-learning. This improvement allows, little by little, e-learning to be promoted and adopted by several educational structures around the world. Neural networks, widely used in various performance prediction works, have made several exploits. However, factors that are highly influential in the field of learning have not been explored in machine learning models. For this reason, our study attempts to show the importance of the forgetting factor in the learning system. Thus, to contribute to the improvement of accuracy in performance predictions. The interest being to draw the attention of researchers in this field to very influential factors that are not exploited. Our model takes into account the study of the forgetting factor in neural networks. The objective is to show the importance of attenuation the forgetting, on the quality of performance predictions in e-learning. Our model is compared to those based on Random Forest and linear regression algorithms. The results of our study show first that neural networks (95.20%) are better than Random Forest (95.15%) and linear regression (93.80%). Then, with the attenuation of forgetting, these algorithms give 96.63%, 95.85% and 93.80% respectively. This work allowed us to show the great relevance of oblivion in neural networks. Thus, the exploration of other unexploited factors will make better performance prediction models.

This paper addresses a production and distribution problem in a supply chain. The supply chain consists of a plant with no storage capacity that produces only one type of product. The manufactured products are then transported to a depot for storage. Customers demand is met by a homogeneous fleet of vehicles that begins and ends their trips at the depot. The objective of the study is to minimize the overall cost of production, inventory and transport throughout the supply chain. A Branch-and-Cut and a hybrid Two Phases Decomposition Heuristic using a Mixed Integer Programming and a Genetic Algorithm have been developed to solve the problem.

The cloud IaaS easily offers to have homogeneous multi-core machines (whether they are "bare metal" machines or virtual machines). On each of these machines, there can be high-performance input-output SSD disks. That allows to distribute the files produced during the execution of the workflow to different machines in order to minimize the additional costs associated with transferring these files. In this paper, we propose a scheduling algorithm called WSRDT (Workflow Scheduling Reducing Data Transfers) whose purpose is to minimize the makespan (execution time) of data-intensive workflows by reducing transfers data between dependent tasks on the network. Intermediate files produced by tasks are stored locally on the disk of the machine where the tasks were executed. We experimentally verify that the increase in the number of cores per machine reduces the additional cost due to data transfers on the network. Experiences with a veritable workflow show those advantages of the algorithms presented. Data-driven scheduling significantly reduces the execution time and the volume of data transferred on the network, our approach outperforms one of the best state-of-the-art algorithms that we have adapted with our hypotheses.

In this article, we present a chatbot model that can automatically respond to learners’ concerns on an online training platform. The proposed chatbot model is based on an adaptation of the similarity of Dice to understand the concerns of learners. The first phase of this approach allows selecting the pre-established concerns that the teacher has in a knowledge base which are closest to those posed by the learner. The second phase consists of selecting among these k most appropriate concerns based on a measure of similarity built on the concept of domain keywords. The experimentation of the prototype of this chatbot makes it possible to find the adequate answers. In the case, where the question refers to a question from the teacher, the learner is asked if the question identified is the one he was referring to. If he answers in the affirmative, the instructions associated with his request are sent to him. If not, the learner’s concern is sent to the human tutor. The hybridization of this chatbot with the human agent comes to enrich the initial knowledge base of the chatbot. The results obtained with the concept based on the keywords of the domain are encouraging. The learner’s comprehension rate is above 50% when applying the concept of domain keywords while the measure of Dice is below 50%.

Belief entropy, which represents the uncertainty measure between several pieces of evidence in the Dempster-Shafer framework, is attracting increasing interest in research. It has been used in many applications and is mainly based on the theory of evidence. To quantify uncertainty, several measures have been proposed in the literature. These measures, sometimes in extended or hybrid forms, use the Shannon entropy principle to determine uncertainty degree. However, the failure to consider the scale of the frame of discernment framework remains an open issue in quantifying uncertainty. In this paper, we propose a new uncertainty measure that takes into account the power set of the frame of discernment. After analysing the different existing methods, we show the performance and effectiveness of our proposed approach.

Following the many natural disasters and global socio-economic upheavals of the 21st century, the concept of resilience is increasingly the subject of much research aimed at finding appropriate responses to these traumas. However, most existing work on resilience is limited to a broad cross-disciplinary panel of non-operational theoretical approaches. Thus, the study of the processes of social resilience is confronted with difficulties of modeling and a lack of appropriate analysis tools. However, the existing stratification methods are too general to take into account the specificities of the resilience and are difficult to use for non-specialists in modeling. In addition, most traditional methods of partition research have limitations including their inability to effectively exploit the research space. In this paper, we propose a classification algorithm based on the technique of genetic algorithms and adapted to the context of social resilience. Our objective function, after penalization by two criteria, allows to explore widely the space of research for solutions while favoring classes quite homogeneous and well separated between them.

The purpose of this paper is to provide a decision support tool based on a mathematical model and an algorithm that can help in the assessment of the level of vulnerability of children in Cote d'Ivoire. So, this study was conducted in three phases, the first one includes the settlement of a data warehouse. Then the second involves the application of probabilistic model. The final phase deals with the classification of children considered vulnerable in descending order from the most to the least vulnerable. The purpose of this classification is to better manage the resources of donors to support vulnerable children. This work is part of the activities of UMRI The resilience of Cote d’Ivoire. This is to propose mathematical and computational tools to facilitate the work of the Centre for social resilience. The use of the context of children made vulnerable due to crises or diseases is an example of practical application of our social resilience model

The flexible optical networks are the promising solution to the exponential increase of traffic generated by telecommunications networks. They combine flexibility with the finest granularity of optical resources. Therefore, the flexible optical networks position themselves as a better solution than conventional WDM network. In the operational phase, traffic of connections fluctuates. In fact, the user’s need is not the same during day periods. Such traffic may experiment evidence of rising working hours, end of months or years and decreases during the night or on holidays. This variation requires the expansion or contraction of the number of frequency slots allocated to a connection to match the exact needs of the moment. The expansion of the traffic around the reference frequency of connection may lead to blockage because it must share frequency slots with neighboring connections in compliance with the constraints of continuity, contiguity, and non-overlapping. In this study, we offer a technique for allocating frequency slots for time-varying traffic connections. We share out the additional traffic load on different spectrum paths by respecting the constraint of time synchronization related to the differential delay to reduce the blocking rate due to traffic fluctuation.

International audience; Efficient reconfiguration of optical multicast trees in wavelength division multiplexing (WDM) networks is required. Multimedia applications which consume a huge bandwidth, require multicasting. So, multicast concept is extended to optical networks to improve performance. Today, networks are facing many phenomena such as changes in the traffic model, failures, additions or deletions of some network resources due to a maintenance operation. To cope with these phenomena, network operators compute new topology according to the applications requirements. Some real-time multicast applications are not indulgent with lightpath interruptions. So the configuration of the network must be done as quickly as possible to be spontaneously deal with the problem before other events appear and without connection interruption. To the best of our knowledge, there is no work in the literature that considers the reconfiguration of an optical multicast tree to another one without connection interruption. We prove that it is impossible to reconfigure any initial tree into any final tree using only one wavelength and without connection interruption. We propose in this paper BpBAR_2 method, using several wavelengths to reconfigure optical WDM network. This algorithm does tree reconfiguration without lightpath interruption, reduce the reconfiguration setup time and the cost of wavelengths used.

The standard 802.11b became a reference as regards data-processing communication wireless, but its system of safety presents several vulnerabilities. This is why of many encodings and other technical solutions came to assistance of the 802.11b. Even if these solutions do not resolve in a final way the problem of safety, it should be noted that they strongly improve it. We propose to tackle the problem of safety met in the networks 802.11b by the study of the various evolutions concerning the systems of safety and we present the architecture of a solution of safety based on the use of a gate Web and standard IEEE 802.1x. Through this architecture we show that it is possible to implement an architecture which can improve safety in wireless LAN 802.11b.

Cognitive radio devices have been considered as a key technology for next-generation of wireless communication. These devices in the context of IEEE 802.11 standards and IEEE 802.16 standards, can opportunistically utilize the wireless spectrum to achieve better user performance and improve the overall spectrumutilization efficiency, mainly in the unlicensed 5 GHz bands. However, opportunistic use of wireless spectrum creates news problems such as peaceful coexistence with other wireless technologies, such as the radiolocation systems, as well as understanding the influence of interference that each of these networks can create. In this paper, we suggest a dynamic access model that considerably reduces this interference and allows efficiency and fairness use of the wireless spectrum., {"references":["Shared Spectrum Compagny, \"Spectrum occupancy measurement.\" site\ninternet, http://www.sharedspectrum.com/measurements/.","M. O¨ ner and F. K. Jondral, \"On the extraction of the channel allocation\ninformation in spectrum pooling systems,\" IEEE Journal on Selected\nAreas in Communications, vol. 25, no. 3, pp. 558-565, 2007.","J. Mitola, \"The software radio architecture\" IEEE Communications, Vol.\n33, N°5, 1995, pp. 26-38.","D. Cˇ abric' and R. W. Brodersen, \"Physical layer design issues unique\nto cognitive radio systems,\" in Proceedings of the 16th IEEE\nInternational Symposium on Personal, Indoor and Mobile Radio\nCommunications (PIMRC -05), pp. 759-763, Berlin, Germany,\nSeptember 2005.","Y. Xing, R. Chandramouli, S.Mangold, and S. S. N, \"Dynamic spectrum\naccess in open spectrum wireless networks,\" IEEE Journal on Selected\nAreas in Communications, vol. 24, no. 3, pp. 626-637, 2006.","Natasha Devroye, Mai Vu, and Vahid Tarokh \"Achievable Rates and\nScaling Laws for Cognitive Radio Channels\". EURASIP Journal on\nWireless Communications and Networking, Volume 2008.","H. Gintis, Game Theory Evolving: A Problem-Centered Introduction to\nModeling Strategic Behavior. Princeton University Press, 2000.","X. Jing and D. Raychaudhuri, \"Spectrum co-existence of IEEE 802.11b\nand 802.16a networks using CSCC etiquette protocol\" in Proceedings of\nthe 1st IEEE Symposium on New Frontiers in Dynamic SpectrumAccess\nNetworks (DySPAN -05), pp. 243-250, Baltimore, Md, USA, November\n2005.","Dipankar Raychaudhuri and Xiangpeng Jing. \"A spectrum etiquette\nprotocol for efficient coordination of radio devices in unlicensed bands\".\n14th IEEE PIMRC2003, September 2003.\n[10] G. Bianchi, \"Performance analysis of the IEEE 802.11 distributed\ncoordination function\" IEEE Journal on Selected Areas in\nCommunications, vol. 18, no. 3, pp. 535-547, 2000.\n[11] Industrie Canada, \"Gestion du spectrum et telecommunication.\" Site\ninternet, http://www.ic.gc.ca/eic/site/smt-gst.nsf/fra/.\n[12] T. A. Weiss and F. K. Jondral, \"Spectrum pooling: an innovative\nstrategy for the enhancement of spectrum efficiency,\" IEEE\nCommunications Magazine, vol. 42, no. 3, pp. S8-S14, 2004.\n[13] S. Gilbert, \"Introduction to linear Algebra, \"Wellesley-Cambridge\nPress\". 1998.\n[14] S. Mangold and K. Challapali, \"Coexistence of wireless networks in\nunlicensed frequency bands\". Wireless World Research Forum #9\nZurich Switzerland, July 2003.\n[15] Steven De Jonc, Karl Tuyls and Katja Verbeeck \"Artificial agents\nlearning human fairness\". Proceedings of the 7th international joint\nconference on Autonomous agents and multiagent systems, Volume 2\nPages: 863-870, 2008, ISBN: 978-0-9817381-1-6.\n[16] Yiping Xing and R. Chandramouli Stefan Mangold and Sai Shankar N\n\"Analysis and Performance Evaluation of a Fair Channel Access\nProtocol for Open Spectrum Wireless Networks\". IEEE International\nConference, volume 2, pp. 1179-1183, May 2005 ISBN: 0-7803-8938-7.\n[17] Durga P. Satapathy and Jon M. Peha \"Spectrum Sharing Without\nLicenses: Opportunities and Dangers\" Proceedings of The\nTelecommunications Policy Research Conference (TPRC), Section 3, pp.\n15-29, 1996.\n[18] C.T. Chou, Hyoil, K., Sai Shankar, N., and Shin, K. G., \"Spectrum\nagility radio for broadband applications\" EETimes In Focus Article,\nAug. 23.\n[19] C.T. Chou, Hyoil, K., Sai Shankar, N., and Shin, K. G., \"Spectrum\nagility radio : radio resource measurements for opportunistic spectrum\nusage\". IEEE Globecom 2004, Dallas TX, USA, Nov. 2004.\n[20] C.T. Chou, Hyoil, K., Sai Shankar, N., and Shin, K. G., \"What and how\nmuch to gain from Spectrum Agility\" Submitted to IEEE/ACM Trans.\nOn Networking, June 2004."]}

The security of their network remains the priorities of almost all companies. Existing security systems have shown their limit; thus a new type of security systems was born: honeypots. Honeypots are defined as programs or intended servers which have to attract pirates to study theirs behaviours. It is in this context that the leurre.com project of gathering about twenty platforms was born. This article aims to specify a model of honeypots attack. Our model describes, on a given platform, the evolution of attacks according to theirs hours. Afterward, we show the most attacked services by the studies of attacks on the various ports. It is advisable to note that this article was elaborated within the framework of the research projects on honeyspots within the LABTIC (Laboratory of Information Technologies and Communication)., {"references":["E. Alata, M Dacier ÔÇÿ-Leurré.com : retour d-expérience sur\nplusieurs mois d-utilisation d-un pot de miel distribué\nmondialement--.","Home Page du projet Honeynet,\nhttp ://www.honeynet.org/, dernière visite 19 /09/2005.","L. Spitzner, Honeypots: Tracking Hackers, Add.-Wesley, ISBN\nfrom-321-10895-7, 2002.","French Honeynet Project, http: //honeynet.rstack.org.","F. Pouget, T. Holz, _A Pointillist Approach for Comparing\nHoneypots_, Proc. Conference on Detection of Intrusions and\nMalware & Vulnerability Assessment (DIMVA 2005), Vienne\n9.","ACI Sécurité et Informatique, http ://acisi.loria.fr.","Fabien Pouget. Leurré.com, the Eurecom Honeypot Project\nintroduction. http://www.eurecom.fr/~pouget/leurrecom.htm.","NGUYEN Programme d-alerte base sur des pots de mile,\nseptembre 2005.","VMware Corporation Home Page, http: //www.vmware.com\n[10] Honeyd Home page,\nhttp: //www.citi.umich.edu/u/provos/honeyd\n[11] https://riviera.eurecom.fr/.\n[12] fr.wikipedia.org/wiki/Loi_normale; last access sept 2006.\n[13] Honeypot-Based Forensics F Pouget and M Dacier, Proceedings\nof the Asia Pacific Information Technology Security\nConference, (Auscert), 2004.\n[14] What-s port 445 used for in windows 2000/XP; www.petri.co.il\n[15] Global Intrusion Detection: Prelude Hybrid IDS Mathieu\nBlanc1, Laurent Oudot1, and Vincent Glaume, rapport de\nrecherche 2002.\n[16] The Value of Honeypots, Part Two: Honeypot Solutions and\nLegal Issues by Lance Spitzner with extensive help from Marty\nRoesch last updated October 23, 2001.\n[17] The value of Honeypots, Part one: Definitions and Values of\nHoneypots Lance Spitzner 2001-10-10."]}

The third generation (3G) of cellular system adopted the spread spectrum as solution for the transmission of the data in the physical layer. Contrary to systems IS-95 or CDMAOne (systems with spread spectrum of the preceding generation), the new standard, called Universal Mobil Telecommunications System (UMTS), uses long codes in the down link. The system is conceived for the vocal communication and the transmission of the data. In particular, the down link is very important, because of the asymmetrical request of the data, i.e., more remote loading towards the mobiles than towards the basic station. Moreover, the UMTS uses for the down link an orthogonal spreading out with a variable factor of spreading out (OVSF for Orthogonal Variable Spreading Factor). This characteristic makes it possible to increase the flow of data of one or more users by reducing their factor of spreading out without changing the factor of spreading out of other users. In the current standard of the UMTS, two techniques to increase the performances of the down link were proposed, the diversity of sending antenna and the codes space-time. These two techniques fight only fainding. The receiver proposed for the mobil station is the RAKE, but one can imagine a receiver more sophisticated, able to reduce the interference between users and the impact of the coloured noise and interferences to narrow band. In this context, where the users have long codes synchronized with variable factor of spreading out and ignorance by the mobile of the other active codes/users, the use of the sequences of code pseudo-noises different lengths is presented in the form of one of the most appropriate solutions., {"references":["Houda KHERDHER ? Mémoire pour grade de ma├«tre ès science : Effet\ndes codes correcteurs d-erreurs sur les systèmes CDMA ├á taux multiples,\nUniversité Laval.","Direct sequence spread spectrum sequences par Christophe Boulanger\n(Sagem-Paris, Rue Watt, 75013 Paris), Gérard Loubet (INPG/LIS,\nCampus Universitaire, 38402 St Martin D'heres), Jean René Lequepeys\n(CEA-LETI, CEA GRENOBLE, Rua des Martyrs, 38054 GRENOBLE)\net Laurent Ouvry CEA-LETI, Cea Grenoble, Rua des Martyrs, 38054\nGrenoble).","Statistique d-ordre supérieur pour le traitement du signal, J.L.Lacoume,\nP.O.Ambland, P.Comon, (Masson, paris, 1997).","Pursley, M.B., \"Performance Evaluation for Phase-coded Spread-\nSpectrum Multiple-Acces Communication. Part 1: System Analysis\".\nIEEE Transactions on Communications, Vol 1. COM-25. No. 8, pp. 795-\n799, Ao├╣t 1977.","Pursley, M.B. et Sarwate, D.V., \"Performance Evaluation for Phasecoded\nSpread-Spectrum Multiple-Acces Comrnunication. Part 2: Code\nSequence Analysis\". IEEE Transactions on Communications, Vol.\nCOM-25, No. 8, pp. 800-803, Ao├╣t 1977.","Pursley, M.B. et ROEFS, H.F.A., \"Numerical Evaluation of Correlation\nParameters for Optimal Phases of Binary Shift-Register Sequences\".\nIEEE Transactions on Communications, Vol. COM-27, NO. 10, pp.\n1597- 1604, October 1979.","Ottosson, T. et Svensson, A., \"Multi-Rate Schemes in DS/CDMA\nSystems\". Proc. IEEE VTC'95, Chicago, Juillet 1995.","Analyse des systèmes linéaires (chapitre 1 ├á 4) Jean COAT et Jean-\nMarie Escane."]}

Internet is without any doubt the fastest and effective mean of communication making it possible to reach a great number of people in the world. It draws its base from exchange points. Indeed exchange points are used to inter-connect various Internet suppliers and operators in order to allow them to exchange traffic and it is with these interconnections that Internet made its great strides. They thus make it possible to limit the traffic delivered via the operators of transits. This limitation allows a significant improvement of the quality of service, a reduction in the latency time just as a reduction of the cost of connection for the final subscriber. Through this article we will show how the installation of an IXP allows an improvement and a diversification of the services just as a reduction of the Internet connection costs., {"references":["RFC 1633: Integrated Services in the Internet Architecture: An\nOverview, R. Braden, D. Clark, S. Shenker, 1994.","RFC 1889: RTP: A Transport Protocol for Real-Time Applications H.\nSchulzrinne, S. Casner, R.Frederick, V. Jacobson, 1996.","RFC 2205: Resource ReSerVation Protocol (RSVP) -- Version 1\nFunctional Specification, R. Braden, Ed., L. Zhang, S. Berson, S.\nHerzog, S. Jamin 1997.","RFC 2211: Specification of the controlled load Network element Service\nWroclawsky 1997.","RFC 2212: Specification of Guaranteed Quality of Service. Shenker, C.\nPartridge, R. Guerin 1997.","RFC 2215: General Characterization Parameters for Integrated Service\nNetwork Elements. S. Shenker, J. Wroclawski 1997.","RFC 2474: Definition of the Differentiated Services Field (DS Field) in\nthe IPv4 and IPv6 Headers. K. Nichols, S. Blake, F. Baker, D. Black\n1998.","Halfway Proposition, http://www.afrispa.org/Initiatives.htm","Routing in the Internet John W. Stewart III, BGP4 Inter- Domain,\njstewart@juniper.net\n[10] Association Africaine des Fournisseurs de services Internet,\nhttp://www.afrispa.org/\n[11] BGP Case Studies Document ID: 26634 [en ligne],\nhttp://www.cisco.com/warp/public/459/bgp-toc.html\n[12] Via l-Afrique: Création de point d-échange Internet (IXP) locaux et\nrégionaux en vue de réaliser des économies en termes financiers et de\nlargeur de bande. Russel Southwood, Union International des\nTélécommunications, CRDI 2004.\n[13] Enic-TELECOM: Historique de la QoS\nhttp://wapiti.enic.fr/commun/ens/peda/options/ST/RIO/pub/exposes/exp\nosesrio2004ttnfa05/ MalygaSokowicz/partie1.htm\n[14] Université Paul Sabatier (Toulouse III) Le modèle DiffServ, André\nAoun 2001 http://www.httr.ups-tlse.fr/pedagogie/cours/tcpip/\ndiffserv/index.html\n[15] Introduction ├á la problématique des Réseaux avec QoS - Plan et\nContexte http://rangiroa.essi.fr/cours/reseau2/02-IREQoS2002-a.pdf\nEric Gressier-Soudan 2002.\n[16] Réseaux IP et Qualité de Service http://www.supinfoprojects.\ncom/fr/2003/ip%5Fnetworks%5Fqos Alan TRANCART\nIngénieur Supinfo Paris Promotion SUPINFO 2003.\n[17] Tout sur MPLS, http://www.frameip.com/mpls Benbella Benduduh et\nJean Marc Fourcade, création du document 2001.\n[18] La qualité de service dans l'Internet, Laurent Toutain, Jean Marie\nBonnin, Octavio Medina, ENST Bretagne - Campus de Rennes, BP 78 -\n35 512 Cesson Sévigné Cedex.\n[19] V. Jacobson, Congestion avoidance and control, Proceeding of the\nACM SIGCOMM, ao├╗t 1988.\n[20] RFC 2581, M. Allman, V. Paxson, W. Stevens, TCP Congestion\nControl. Avril 1999.\n[21] Dimensionnement de DiffServ basé sur des métriques de performance\nIbrahima Niang - Dominique Seret, Université Paris 5, René Descartes\nUFR de Mathématiques et Informatique.\n[22] Les principes d-équité appliqués aux réseaux de télécommunications\nCorrine Touati, Université de Nice Sophia-Antipolis, 2003.\n[23] Traffic Management Specification, Natalie Giroux 1996.\n[24] A Mathematical Framework for Designing a Low-Loss, Low-Delay\nInternet. Network and Spatial Economics. Steven H. Low et\nRayadurgam Srikant. 2003.\n[25] The bargaining problem Econometrics, John F. Nash Jr 1950.\n[26] A game theoretic framework for bandwidth allocation and pricing in\nbroadband networks. Haïkel Yaiche, Ravi R. Mazumdar, and Catherine\nRosenberg 2000.\n[27] Fairness in network optimal flow control: optimality of product forms.\nRavi Mazumdar, Lorne G. Mason, and Christos Douligeris 1991."]}

Nowadays data backup format doesn-t cease to appear raising so the anxiety on their accessibility and their perpetuity. XML is one of the most promising formats to guarantee the integrity of data. This article suggests while showing one thing man can do with XML. Indeed XML will help to create a data backup model. The main task will consist in defining an application in JAVA able to convert information of a database in XML format and restore them later., {"references":["G. Sedrati-Dinet. (2006, June 22). Des formats ouverts pour\nl-interoperabilité dans les administrations. (online). Available:\nhttp://www.ffii.fr/Des-formats-ouverts-pour-l-interoperabilite-dans-lesadministration","J. P. Archambault.(2001, October). XML : vers un format documentaire\nuniversel \" (online). Available:\nhttp://www.epi.asso.fr/revue/articles/a0401a.htm","B. Guerry ,D. Taraborelli (2003, November 4). Why use open format?\n(Online). Available: http://www.openformats.org/main","J. P. Meyniac. (2004, May 28). Format de fichiers, attention danger !\nAvailable : http://www.clionautes.org","Open vs. proprietary formats, 2004. Available:\nhttp://www.openformats.org/en1","Definition of open format, http://www.answers.com/topic/open-format","D. Wilson ÔÇÿ-Sélectionner le bon format texte--, Gazette Linux, Janvier\n2004, Vol. n┬░98. Available: http://ftp.traduc.org/doc-vf/gazettelinux/\nhtml/2004/098/lg98-N.html","T. Boyer (2005, September 5). La norme XML. Supinfo-Projects\nAvailable : http://www.supinfo-projects.com/en/2005/norme_xml/","M. Duperrier. (2003, February 21). XML expliqué ├á mon directeur\ngénéral. (Online). Available:\nhttp://xmlfr.org/documentations/articles/030220-0001\n[10] CommentCaMarche. Présentation de XML. (Online) . Available :\nhttp://abdi.pureweb.fr/telechargements/xml.doc\n[11] XML parser. http://www.w3schools.com/xml/xml_parser.asp\n[12] OASIS ODF Adoption TC. (2006, December 10). Les avantages du\nformat OpenDocument. (Online). Available: http://www.oasisopen.\norg/committees/download.php/21451/oasis_odf_advantages_fr_10\ndec2006.odt"]}

Multicast transmissions allow an host (the source) to send only one flow bound for a group of hosts (the receivers). Any equipment eager to belong to the group may explicitly register itself to that group via its multicast router. This router will be given the responsibility to convey all information relating to the group to all registered hosts. However in an environment in which the final receiver or the source frequently moves, the multicast flows need particular treatment. This constitutes one of the multicast transmissions problems around which several proposals were made in the Mobile IPv6 case in general. In this article, we describe the problems involved in this IPv6 multicast mobility and the existing proposals for their resolution. Then architecture will be proposed aiming to satisfy and optimize these transmissions in the specific case of a mobile multicast receiver in NC-HMIPv6 environment., {"references":["S. Bhattacharyya, \"An Overview of Source-Specific Multicast (SSM)\",\nRFC 3569, July 2003.","O. Christ, T. C. Schmidt, and M. Waehlisch, \"A Light-Weight\nImplementation Scheme of the Tree Morphing Protocol for Mobile\nMulticast Sources\", Proc. of 33rd Euromicro Conf., IEEE/CS, Sept.\n2007.","G. Cizault, \"IPv6: Théorie et pratique\", 4ème Edition, 2006.","S. Deering, W. Fenner and B. Haberman, \"Multicast Listener Discovery\n(MLD) for IPv6\", RFC 2710, October 1999.","B. Fenner, M. Handley, H. Holbrook, and I. Kouvelas, \"Protocol\nIndependent Multicast - Sparse Mode PIM-SM): Protocol Specification\n(Revised)\", RFC 4601, August 2006.","A. Garyfalos, and K. Almeroth, \"A Flexible Overlay Architecture for\nMobile IPv6 Multicast\", IEEE Journ. on Selected Areas in Comm., 23\n(11), pp. 2194-2205, November 2005.","A. Garyfalos, K. Almeroth, and K. Sanzgiri, \"Deployment Complexity\nVersus Performance Efficiency in Mobile Multicast\",\nhttp://imj.ucsb.edu/papers/BROADWIM-04.pdf.gz","K. Guillouard, Y. Khouaja, P. Bertin, and J. M. Bonnin, \"Gestion\nHiérarchique de la Mobilité IPv6 Contr├┤lée par le réseau\", http://wwwrp.\nlip6.fr/dnac/3.2-khouaja-article.pdf, 2002.","M. Handley, I. Kouvelas, T. Speakman, and L. Vicisano, \"Bi-directional\nProtocol Independent Multicast (BIDIR-PIM)\", draft-ietf-pim-bidir-\n09.txt, February 2007.\n[10] H. Holbrook and B. Cain, \"Source-Specific Multicast for IP\", RFC\n4607, August 2006.\n[11] C. Jannetau, Y. Tian,, S. Csaba, \"Comparison of Three Approaches\nTowards Mobile Multicast\", www.comnets.rwth- aachen.de/~o_drive/\npublications/ist-summit-2003-IPMobile Multicast-paperv2.0.pdf.\n[12] C. Jelger, \"Multipoint et Mobilité: Optimsations pour IPv6\", LSIITUMR\n7005 - CNRS/ULP, Université Louis Pasteur, mai 2002.\n[13] C. Jelger, T. Noel, \"Multicast for Mobile Hosts in IP Networks: Progress\nand Challenges\", IEEE Wireless Comm., pp 58-64, Oct. 2002.\n[14] C. Jelger, and T. Noel, \"Supporting Mobile SSM sources for IPv6\n(MSSMSv6)\", Internet Draft (work in progress, expired), January 2002.\n[15] D.B. Johnson, C. Perkins and J. Arkko,\"Mobility Support in IPv6\", RFC\n3775, June 2004.\n[16] Kellil, M., Romdhani, Kellil, H.-Y. Lach, A. Bouabdallah, and H.\nBettahar, \"Multicast Receiver and Sender Access Control and its\nApplicability to Mobile IP Environments: A Survey\", IEEE Comm.\nSurveys & Tutorials 7(2), pp. 46-70, 2005.\n[17] R. Koodli, \"Fast Handovers for Mobile IPv6\", RFC 4068, July 2004.\n[18] G. Leoleis, G. Prezerakos, and I. Venieris, \"Seamless multicast\nmobility support using fast MIPv6 extensions\", Computer Comm. 29,\npp. 3745-3765, 2006.\n[19] R.C. Lin and K. Cheng, \"Scalable Multicast Protocol in IP-Based\nMobile Networks\", Wireless Networks and Applications, 5, pp. 259-271,\n2000.\n[20] T. Noel, N. Montavont, and P. Bertin, \"Mobilité IPv6 et WLAN:\nExpérimentation et évaluation ├á l'échelle d'un campus\", LSIIT.\nUniversité Louis Pasteur. Strasbourg, décembre 2002, http://wwwrp.\nlip6.fr/dnac/7.1-noel-article.pdf\n[21] C. Perkins, \"IP Mobility Support for IPv4\", RFC 3344, August 2002.\n[22] I. Romdhani, M. Kellil, H.-Y. Lach et. al. \"IP Mobile Multicast:\nChallenges and Solutions\", IEEE Comm. Surveys, 6(1), 2004.\n[23] Romdhani, I., Bettahar, H. and Bouabdallah, A. \"Transparent handover\nfor mobile multicast sources\", in P. Lorenz and P. Dini, eds,\n'Proceedings of the IEEE ICN'06', IEEE Press, 2006.\n[24] H. Soliman, C. Castelluccia, K. El-Malki, and L. Bellier, \"Hierarchical\nMobile IPv6 mobility management\", RFC 4140, August 2005.\n[25] T.C. Schmidt, and M. Waehlisch, \"Multicast Mobility in MIPv6:\nProblem Statement and Brief Survey\", draft-irtf-mobopts-mmcastv6-ps-\n00.txt, May 2007.\n[26] T.C. Schmidt, and M. Waehlisch, \"Seamless Multicast Handover in a\nHierarchical Mobile IPv6 Environment (M-HMIPv6)\", draft-schmidtwaehlisch-\nmhmipv6-04.txt, December 2005.\n[27] Thaler, D. \"Supporting Mobile SSM Sources for IPv6\", Proceedings of\nIETF meeting Dec. 2001, individual.\nURL:www.ietf.org/proceedings/01dec/slides/magma-2.pdf\n[28] R. Vida and L. Costa (Eds.) \"Multicast Listener Discovery Version 2\n(MLDv2) for IPv6\", RFC3810, June 2004.\n[29] R. Vida, L. Costa, and S. Fdida, \"M-HBH - Efficient Mobility\nManagement in Multicast\", Proc. of NGC '02, pp. 105-112, ACM Press\n2002.\n[30] F. Xia, and B. Sarikaya, \"FMIPv6 extensions for Multicast Handover\",\ndraft-xia-mipshop-fmip-multicast-00.txt, September 2006.\n[31] Zhang, H. et al \"Mobile IPv6 Multicast with Dynamic Multicast Agent\",\ndraft-zhang-mipshop-multicast-dma-03.txt, (work in progress), January\n2007."]}

A satured liquid is warmed until boiling in a parallelepipedic boiler. The heat is supplied in a liquid through the horizontal bottom of the boiler, the other walls being adiabatic. During the process of boiling, the liquid evaporates through its free surface by deforming it. This surface which subdivides the boiler into two regions occupied on both sides by the boiled liquid (broth) and its vapor which surmounts it. The broth occupying the region and its vapor the superior region. A two- fluids model is used to describe the dynamics of the broth, its vapor and their interface. In this model, the broth is treated as a monophasic fluid (homogeneous model) and form with its vapor adiphasic pseudo fluid (two-fluid model). Furthermore, the interface is treated as a zone of mixture characterized by superficial void fraction noted α* . The aim of this article is to describe the dynamics of the interface between the boiled fluid and its vapor within a boiler. The resolution of the problem allowed us to show the evolution of the broth and the level of the liquid., {"references":["Bedaux D., Albano A. M., Mazur P., Boundary conditions and non equilibrium thermodynamics, Physica 82A, 1996, pp. 438-462.","Bilicki Z., Michaelides E. E., Thermodynamic of bubbly none equilibrium in liquid-vapor flows, Valter Degruyer, 1997.","Boure J. A., 1978, Two-phase flows and Heat transfer with application to Nuclear reactor Design problem, Hemisphere Pub Corp. Washington, 1978.","Danho E., Non linear distributions theory for jump conditions in two-phase flows instabilities, In journal of Africa Mathematical Union, 1993.","Drew D. A. and Segal L. A., Averaged equations for two-phase flow, Studies in Appl. Math. L, 1971, pp. 205-231.","Drumheller, D. S. and Bedford, A., A theory of liquids with vapor bubbles. J. Acoust. Soc. Am. 667, 1971, pp. 186-200.","Gatignol R., Dynamics of multiphase flows across Interfaces, edited by Annie Steichen, Springer-Verlag, 1996.","Hewitt G. H., Two phase flows and heat transfer with application to nuclear reactor design problems, pp. 1-15.","Hsieh D. Y., On dynamics of bubbly liquids, Advances in applied mechanics 26, 63-13, Academic Press, 1988. [10] Lombard B, Piraux J., Numerical treatment of two-dimensional interfaces for acoustic and elastic waves, Journal of computational physics, 195-1, 2004, pp. 90-116. [11] Properriti, A., Boundary conditions at liquid-vapor Interfaces, Meccanica 19, 1979 p p. 123-136. [12] Roger P. and Thomas D. T., Computational Methods for Fluids Flows, Springer-Verlag New York, Heidelberg Berlin, 1983. [13] William G. and Kevin O., ''On the general Equations for Flow in Porous media and their Reduction to Darcy's Law'' Water Ressources Research, Vol. 12. ,n┬░2, April 1976 pp. 148-154."]}

Nowadays, many scientific applications need to be parallelized. This parallelization allows to complete simultaneously several independent tasks with the same application on different processor cores. Thus, the execution time (makespan) of such a application can be shortened compared to its sequential version (where all the tasks are executed on the same processor core one after the other). Parallelizable applications are as diverse and varied. There are many scientific computing application in the fields of drug research, nuclear simulation, simulation of mechanical properties of machines, astronomical research, banking simulation, image processing, etc.Many applications can be modeled as scientific workflows, i.e. They can be represented by Directed Acyclic Graphs (DAG) where the nodes represent the different tasks of the application to be completed. The arcs represent the dependency constraints between the tasks (a task can only start its execution when all its parent tasks have finished their execution). In scientific workflows, some tasks load input files and/or produce output files during their execution. An output file of a task can be reused as input for another task. This raises the issue of scheduling these tasks and files in order to reduce the impact of file transfers on the network and to minimize the makespan and/or the cost of completing the parallel software, especially when the different processor cores required are not necessarily on the same machine.Scientific workflows used to run mainly on clusters. Today, the IaaS (Infrastructure as a Services) offers of cloud computing providers represent a new execution environment for this type of parallel applications. However, this migration to cloud computing brings new scheduling challenges. Indeed, since on IaaS platforms, resources appear virtually unlimited and each user who wishes to run his application is charged according to the resources used, the major problem that arises is how to find a good compromise between the execution time of his application and the cost of using the resources.We thus propose a solution for this bi-criteria optimization problem of finding a trade-off between the makespan of scientific workflows and the cost of using cloud resources, by conducting this study in several steps. The first step is to suggest a single-criteria optimization algorithm that attempts to minimize the makespan of workflows when the resources to be used are fixed. This algorithm has been compared to the very popular HEFT algorithm.Then, in another study we showed that for the same total number of processor cores, using fewer virtual machines containing many processor cores each one is more beneficial than using more virtual machines each containing fewer processor cores. This is because it significantly reduces the makespan of scientific workflows. We also suggest a faster method of generating a Pareto front from the previously suggested algorithm and running the simulations on fewer platforms than the competing approach which is the MOHEFT algorithm. MOHEFT being the best algorithm in the literature for solving the above mentioned bicriteria problem. It should be recalled that a Pareto front represents the optimal points obtained from the execution of a multi-criteria optimization algorithm. The outcomes show that the suggested approach gives better Pareto fronts compared to MOHEFT in addition to giving more points (thus more choices to the user) in these Pareto fronts compared to those of MOHEFT, and to get out the Pareto fronts in much less time than MOHEFT. Finally, in a last contribution, we suggested a dichotomous search procedure to suggest fewer points than those on the full Pareto front in order to facilitate the user’s choice. This approach eliminates points from the Pareto front that are not interesting in practice, although they are theoretically optimal points because they are not dominated by the other points., Aujourd’hui de nombreuses applications scientifiques nécessitent d’être parallélisées. Cette parallélisation permet d’exécuter simultanément plusieurs tâches indépendantes d’une même application sur des cœurs de processeurs différents. Ainsi on peut considérablement réduire le temps d’exécution (makespan) d’une telle application par rapport à sa version séquentielle (où toutes les tâches s’exécutent sur un même cœur de processeur l’une après l’autre). Les applications parallélisables sont aussi diverses que variées. On trouve de nombreuses applications de calcul scientifique dans les domaines de la recherche de médicaments, de la simulation nucléaire, de la simulation des propriétés mécaniques des engins, de la recherche astronomique, de la simulation bancaire, du traitement d’images, etc.De nombreuses applications sont modélisables sous forme de workflows scientifiques, c’est-à-dire que ces applications peuvent être représentées par des graphes orientés acycliques où les nœuds représentent les différentes tâches de l’application à exécuter. Les arcsreprésentent, quant à eux, les contraintes de dépendances entre les tâches (une tâche ne peut commencer son exécution que lorsque toutes les tâches parentes de cette tâche ont terminé leur exécution). Dans les workflows scientifiques, certaines tâches chargent des fichiers en entrée et/ou produisent des fichiers en sortie lors de leurs exécutions. Un fichier en sortie d’une tâche peut être réutilisé en entrée d’une autre tâche. Il se pose donc la problématique de l’ordonnancement de ces tâches et de ces fichiers afin de réduire l’impact des transferts de fichiers sur le réseau et de minimiser le makespan et/ou le coût d’exécution de l’application parallèle, surtout lorsque les différents cœurs de processeurs sollicités ne se trouvent pas nécessairement sur la même machine.Les workflows scientifiques s’exécutaient principalement sur les grappes de calcul (clusters). Aujourd’hui les offres IaaS (Infrastrure as a Services) des fournisseurs de cloud computing représentent un nouvel environnement d’exécution de ce type d’applications parallèles. Toutefois, cette migration vers le cloud computing entraîne de nouveaux défis d’ordonnancement à relever. En effet, puisque sur les plateformes IaaS, les ressources paraissent virtuellement illimitées et que chaque utilisateur qui souhaite y exécuter son application est facturé en fonction des ressources utilisées, le problème majeur qui se pose est comment trouver un bon compromis entre le temps d’exécution de son application et le coûtd’utilisation des ressources.Nous proposons ainsi une solution pour ce problème d’optimisation bi-critères de recherche de compromis entre le makespan des workflows scientifiques et le coût d’utilisation des ressources du cloud, en menant cette étude en plusieurs étapes. La première étape consiste à proposer un algorithme d’optimisation monocritère qui tente de minimiser le makespan des workflows lorsque les ressources à utiliser sont fixées. Cet algorithme a été comparé au très populaire algorithme HEFT.Ensuite, dans une autre étude nous montrons que pour un même nombre total de cœurs de processeurs souhaité, utiliser moins de machines virtuelles contenant de nombreux cœurs de processeurs chacune est plus bénéfique qu’utiliser plus de machines virtuelles contenant chacune moins de cœurs de processeurs. En effet, cela permet de réduire considérablement le makespan des workflows scientifiques.Nous avons aussi proposé une méthode plus rapide de génération d’un front de Pareto à partir de l’algorithme proposé précédemment et en lançant les simulations sur un nombre réduit de plateformes par rapport à l’approche concurrente qui est l’algorithme MOHEFT. MOHEFT étant le meilleur algorithme de la littérature pour la résolution du problème bicritère sus-énoncé. Il faut rappeler qu’un front de Pareto représente les points optimaux obtenus à l’issu de l’exécution d’un algorithme d’optimisation multicritères. Les résultats obtenus montrent que l’approche proposée donne de meilleurs fronts de Pareto par rapport à MOHEFT en plus de donner plus de points (donc plus de choix à l’utilisateur) dans ces fronts de Pareto par rapport à ceux de MOHEFT, et de sortir les fronts de Pareto en des temps très inférieurs à ceux de MOHEFT. Enfin dans une dernière contribution, nous avons proposé une procédure par recherche dichotomique pour suggérer moins de points que ceux qui sont sur le front de Pareto complet afin de faciliter le choix à l’utilisateur. Cette approche élimine des points du front de Pareto qui ne sont pas intéressants en pratique, bien qu’étant des points optimaux théoriquement car non dominés par les autres points.

Massive Open Online Courses (MOOCs) have seen their numbers increase significantly since the democratization of the Internet. In addition, recently with the COVID-19 pandemic, the trend has intensified. If communication devices such as discussion forums are an integral part of the learning activities of MOOCs, there is still a lack of tools allowing instructors and researchers to guide and finely analyze the learning that takes place there. Dashboards summarizing students' activites are regularly offered to instructors, but they do not allow them to understand collective activities in the forums. From a socio-constructivist point of view, the exchanges and interactions sought by instructors in forums are essential for learning (Stephens, 2014). So far, studies have analyzed interactions in two ways: semantically but on a small scale or statistically and on a large scale but ignoring the quality of the interactions. The scientific contribution of this thesis relates to the proposal of an interactive detection approach of collective activities which takes into account their temporal, semantic and social dimensions. We seek to answer the problem of detecting and observing the collective dynamics that take place in MOOC forums. By collective dynamic, we mean all the qualitative and quantitative interactions of learners in the forums and their temporal changes. We want to allow instructors to intervene to encourage these activities favorable to learning. We rely on studies (Boroujeni 2017, Dascalu 2017) which propose to combine statistical analysis of interactions and automatic language processing to study the flow of information in forums. But, unlike previous studies, our approach is not limited to global or individual-centered analysis. We propose a method of designing indicators and dashboards allowing changes of scales and customization of views in order to support instructors and researchers in their task of detecting, observing and analyzing collective dynamics. To support our approach, we set up questionnaires and conducted semi-structured interviews with the instructors. As for the evaluation of the first indicators built at each iteration of our approach, we used various data sources and formats: Coursera (CSV), Hangout (JSON), Moodle (SQL).; Les formations à distance en ligne, en particulier les MOOC, voient leurs effectifs augmenter depuis la démocratisation d'Internet. Malgré leur popularité croissante ces cours manquent encore d'outils permettant aux instructeurs et aux chercheurs de guider et d'analyser finement les apprentissages qui s'y passent. Des tableaux de bord récapitulant l'activité des étudiants sont régulièrement proposés aux instructeurs, mais ils ne leur permettent pas d'appréhender les activités collectives, or du point vue socio-constructiviste, les échanges et les interactions que les instructeurs cherchent généralement dans les forums sont essentiels pour les apprentissages (Stephens, 2014). Jusqu'à présent, les études ont analysé les interactions soit sémantiquement mais à petite échelle, soit statistiquement et à grande échelle mais en ignorant la qualité des interactions. La proposition de cette thèse est une nouvelle approche de détection interactive des activités collectives qui prend en compte à la fois leurs dimensions temporelles, sémantiques et sociales. Nous cherchons un moyen de permettre aux instructeurs d'intervenir et d'encourager les dynamiques collectives qui sont favorables pour les apprentissages. Ce que nous entendons par "dynamique collective", c'est l'évolution des interactions à la fois qualitatives et quantitatives, des apprenants dans des forums. Nous nous appuyons sur des études (Boroujeni 2017, Dascalu 2017) qui proposent d'associer l'analyse statistique des interactions et le traitement automatique de la langue, pour étudier les flux d'informations dans les forums. Mais, à la différence des études précédentes, notre approche ne se limite pas à une analyse globale ou centrée sur un individu. Nous proposons une méthode de conception d’indicateurs et de tableaux de bord permettant les changements d'échelles et la personnalisation des vues afin de soutenir les instructeurs et les chercheurs dans leur tâche de détection, d'observation et d'analyse des dynamiques collectives de sous-groupes d'apprenants.

In this thesis, we address the problem of the quality of information in Internet of Things. One of the main challenges of this concept is to integrate intelligence into systems or applications in order to make them autonomous. It is no longer a question of the system taking action when the system obtains information, but of carrying out a verification step before any decision-making. Indeed, informations provided by sensors can be subject to many imperfections that can obstruct decision making. To solve these problems related to quality of information, we proposed two fusion approaches based on Dempster-Shafer theory. The first approach consists to quantify the uncertainty of data from information sources. This measure is based on the belief entropy, and takes into account the shortcomings of existing measures. The second approach, called ABC_IoT, is a pre-processing method to study the problem of information veracity in IoT applications. The principle of ABC_IoT, to ensure the veracity of multi-source information, is to use information from other sources to improve decision-making. To do this, we use two elements necessary for a good quality of information: the uncertainty quantification in the sources of information and the reliability of the sources of information. For uncertainty quantification, we use the new uncertainty measurement. In addition, we use two concepts of reliability to assess trust in information sources. We illustrate our contributions in the field of smart cities where the use of ABC_IoT helps to ensure better decision-making., Dans cette thèse, nous abordons le problème de la qualité de l’information dans l’Internet des Objets, un nouveau paradigme connu aussi sous l’appellation objets connectés. L’un des principaux enjeux de ce concept consiste à intégrer de l’intelligence dans les systèmes ou applications afin de les rendre autonomes. Il ne s’agit plus pour le système de passer directement à l’action lorsqu’il obtient une information, mais de mener une étape de vérification avant toute prise de décision. En effet, les informations issues des capteurs peuvent être sujettes à de nombreuses imperfections pouvant entraver la prise de décision. Pour apporter une solution à ces problèmes liés à la qualité de l’information, nous proposons deux approches de fusion basées sur la théorie des croyances de Dempster-Shafer. La première approche est une mesure permettant de quantifier l’incertitude dans l’information. Cette mesure est basée sur l’entropie des croyances, et tient compte des insuffisances des mesures existantes. La deuxième approche dénommée ABC_IoT, est une méthode de pré-traitement pour étudier le problème de la véracité des informations dans les applications IoT. Le principe de l’ABC_IoT, pour vérifier la véracité des informations multisources, consiste à utiliser des informations issues de plusieurs sources pour améliorer la prise de décision. Pour ce faire, nous utilisons deux éléments nécessaires pour une bonne qualité des informations : la quantification des incertitudes et la fiabilité des sources d’information. Concernant la quantification de l’incertitude, nous utilisons la nouvelle mesure de l’incertitude. De plus, nous utilisons deux notions de fiabilité pour évaluer la confiance au niveau des sources d’information. Nous illustrons nos contributions dans le domaine des villes intelligentes où l’utilisation de l’ABC_IoT permet d’assurer une meilleure prise de décision.