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Autonomous Priority Based Routing for Online Social NetworksOthman, Salem 14 June 2018 (has links)
No description available.
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Some new localized quality of service models and algorithms for communication networks : the development and evaluation of new localized quality of service routing algorithms and path selection methods for both flat and hierarchical communication networksMustafa, Elmabrook B. M. January 2009 (has links)
The Quality of Service (QoS) routing approach is gaining an increasing interest in the Internet community due to the new emerging Internet applications such as real-time multimedia applications. These applications require better levels of quality of services than those supported by best effort networks. Therefore providing such services is crucial to many real time and multimedia applications which have strict quality of service requirements regarding bandwidth and timeliness of delivery. QoS routing is a major component in any QoS architecture and thus has been studied extensively in the literature. Scalability is considered one of the major issues in designing efficient QoS routing algorithms due to the high cost of QoS routing both in terms of computational effort and communication overhead. Localized quality of service routing is a promising approach to overcome the scalability problem of the conventional quality of service routing approach. The localized quality of service approach eliminates the communication overhead because it does not need the global network state information. The main aim of this thesis is to contribute towards the localised routing area by proposing and developing some new models and algorithms. Toward this goal we make the following major contributions. First, a scalable and efficient QoS routing algorithm based on a localised approach to QoS routing has been developed and evaluated. Second, we have developed a path selection technique that can be used with existing localized QoS routing algorithms to enhance their scalability and performance. Third, a scalable and efficient hierarchical QoS routing algorithm based on a localised approach to QoS routing has been developed and evaluated.
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Dynamic vehicle routing : solution methods and computational tools / Méthodes de résolution et outils informatiques pour les tournées de véhicules dynamiquesPillac, Victor 28 September 2012 (has links)
Les activités de transport jouent un rôle crucial autant dans le domaine de la production que dans celui des services. En particulier, elles permettent d’assurer la distribution de biens et de services entre fournisseurs, unités de production, entrepôts, distributeurs, et clients finaux. Plus spécifiquement, les problèmes de tournées de véhicules (VRP) considèrent la mise au point d’un ensemble de tournées de coût minimal servant la demande en biens ou en services d’un ensemble de clients distribués géographiquement, tout en vérifiant un ensemble de contraintes opérationnelles. Alors qu’il s’agissait d’un problème statique, des avancées technologiques récentes permettent aux organisations de gérer leur flotte de véhicules en temps réel. Cependant, ces nouvelles technologies introduisent également une plus grande complexité dans les tâches de gestion de flotte, révélant une demande pour des outils d’aide à la décision dédiés aux problèmes de tournées de véhicules dynamiques. Dans ce contexte, les contributions de la présente thèse de doctorat s’organisent autour de trois axes : (i) elle présente un état de l’art détaillé des problèmes de tournées dynamiques; (ii) elle introduit des frameworks d’optimisation génériques adaptés à une grande variété de problèmes ; (iii) elle définit un problème de tournées novateur et aux nombreuses applications. / Within the wide scope of logistics management,transportation plays a central role and is a crucialactivity in both production and service industry.Among others, it allows for the timely distributionof goods and services between suppliers, productionunits, warehouses, retailers, and final customers.More specifically, Vehicle Routing Problems(VRPs) deal with the design of a set of minimal costroutes that serve the demand for goods orservices of a set of geographically spread customers,satisfying a group of operational constraints.While it was traditionally a static problem, recenttechnological advances provide organizations withthe right tools to manage their vehicle fleet in realtime. Nonetheless, these new technologies alsointroduce more complexity in fleet managementtasks, unveiling the need for decision support systemsdedicated to dynamic vehicle routing. In thiscontext, the contributions of this Ph.D. thesis arethreefold : (i) it presents a comprehensive reviewof the literature on dynamic vehicle routing ; (ii)it introduces flexible optimization frameworks thatcan cope with a wide variety of dynamic vehiclerouting problems ; (iii) it defines a new vehicle routingproblem with numerous applications.
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Outils pour l'optimisation de la consommation des véhicules électriques / Optimization tools for electric vehicles energy consumptionBaouche, Fouad 02 June 2015 (has links)
Le contexte écologique et économique actuel incite les autorités et le public à la réduction des émissions de CO2 et les dépendances vis-à-vis des hydrocarbures. Le transport représente 23 % des émissions de polluants dans le monde, et ce chiffre passe à 39 % pour la France. L’adoption de nouvelles solutions de transport est primordiale pour la réduction de ces émissions. L’électromobilité représente une alternative viable aux véhicules thermiques conventionnels. Si les véhicules électriques permettent une mobilité avec zéro émission, certaines de leurs caractéristiques empêchent leur développement. Les principaux freins à l’adoption de ce type de véhicules sont l’autonomie limitée, le faible déploiement des stations de recharge en milieu urbain (et extra urbain) ainsi que les temps de recharge importants. Aussi, afin de promouvoir l’usage de ce type de mobilité, il incombe de développer des outils visant à optimiser la consommation électrique tenant compte des caractéristiques liées à ce type de mobilité. C’est l’objectif de ce travail de thèse qui se focalise sur le développement d’outils permettant d’optimiser l’usage de véhicules électriques. Pour ce faire, trois grands axes sont définis : la modélisation des véhicules électriques, l’affectation des stations de recharge et le choix d’éco-itinéraires. La première partie de cette thèse s’intéresse à l’estimation de la consommation des véhicules électriques ainsi qu’à la présentation de la librairie de modèles dynamiques VEHLIB d’estimation de la consommation de ce type de véhicules. La seconde partie est consacrée à l’affectation optimale des stations de recharge. Une méthodologie de déploiement d’infrastructures de recharge est proposée pour la ville de Lyon avec prise en compte de la demande de mobilité issue des enquêtes ménages déplacements. La troisième partie de la thèse s’intéresse à la thématique du choix d’éco-itinéraire (green routing). Celle-ci aboutit à la proposition d’une méthodologie multi-objectif de recherche de stations de recharge afin de déterminer des itinéraires optimaux avec déviation vers ces stations lorsque l’état de charge de la batterie du véhicule ne permet pas de terminer le trajet. Pour finir, une expérimentation a été réalisée à l’aide d’un véhicule électrique équipé de capteurs de position et de consommation pour d’une part valider les méthodologies proposées et d’autre part analyser les facteurs exogènes qui influent sur la consommation des véhicules électriques. / The current ecological and economic context encourages the authorities and the public to reduce CO2 emissions and oil dependence. The transportation is responsible for 23% of pollutants emissions in the world, and this proportion increases up to 37% in France/ The adoption of new transport solutions is primordial to reduce these emissions. Electro mobility is a viable alternative to conventional vehicles. While electric vehicles offer mobility with zero emissions, some of their characteristicds impede their development. The main obtacle to the adoption of these vehicles is the limited autonomy, a sparse distribution of charging stations in urban areas as well as a significant charging time. Also, to promote the use of this type of mobility, it is primordial to develop tools that optimize the energy consumption and take in to account the characteristics associated with this type of mobility. To achieve this, three areas are difined: modeling of electric vehicles, optimized charging station deployment and eco routing. The first part of this theis focuses on the consumption estimation of the electric vehicles and the presentation of the dynamic model library VEHLIB. The second part is dedicated to optimal allocation of charging stations; A methodology for the deployment of electric vehicle charging infrastructures is proposed for the urban area o fthe city of Lyon, taking into account the mobility demand derived from the household travel surveys.The third part of the thesis deals with the eco-routing (green routing). A multi-objective methodology for eco routing with recharge en-route is proposed. The solutions take into account battery state does not permit to finish the trip.Finally, an experiment was carried out using an electric vehicle equipped with position and consumption sensors in order to validate the proposed methodologies and analyze exogenous factor that impact the electric vehicle consumption.
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Optimisation de la conception du design du harnais de commande des véhicules spatiaux / Optimization of the design of the space vehicle control harness designRoynette, Eliott 02 July 2018 (has links)
Il y a soixante ans, le 4 octobre 1957, Spoutnik, le premier satellite artificiel conçu par l’homme, est envoyé dans l’espace. Sa seule fonction est d’émettre un bip radio à des fréquences de 20 et 40 MHz pour démontrer la puissance spatiale de l’URSS. Depuis cette époque les satellites se sont multipliés et leurs missions se sont diversifiées. Aujourd’hui, les missions des satellites sont si variées que certains quittent l’orbite terrestre. On parle dans ce cas de sondes, même si, dans le reste de cette thèse, ils seront inclus dans le terme "satellite". La mission des satellites la plus connue du grand public est la découverte de l’univers et l’exploration interplanétaire avec de célèbres satellites comme le télescope spatial international Hubble ou des sondes comme Rosetta, Voyager 1 et 2, ... Cependant de nos jours, même si l’exploration spatiale reste un enjeu majeur de l’humanité, la plupart des satellites ont des missions plus modestes qui ont pourtant un impact important sur la vie économique et politique. Les satellites en question ont aujourd’hui deux buts : la défense et le commercial. Dans les deux cas on peut diviser les satellites en deux groupes distincts : les satellites d’observation et les satellites de télécommunication. Pour fonctionner tous ces satellites utilisent un harnais électrique. Le harnais électrique regroupe tous les câbles présents dans le satellite et qui ne transportent pas de données client. Dans le cadre de cette thèse nous nous intéressons à l’optimisation de la conception du harnais électrique des satellites. / Sixty years ago, on October 4, 1957, Sputnik, the first man-made artificial satellite, was sent into space. Its only function is to emit a radio beep at frequencies of 20 and 40 MHz to demonstrate the space power of the USSR. Since then, satellites have been multiple and their missions have diversified. Today, the missions of the satellites are so varied that some leave Earth's orbit. We speak in the case of probes, even if, in the rest of this thesis, they will be included in the term "satellite". The best-known satellite mission of the general public is the discovery of the universe and interplanetary exploration with satellite satellites such as the Hubble International Space Telescope or probes such as Rosetta, Voyager 1 and 2, ... nevertheless nowadays Although space exploration remains a major issue for humanity, most satellites have smaller missions that have a significant impact on economic and political life. The satellites in question today have two goals: defense and commercial. In both cases the satellites can be divided into two distinct groups: observation satellites and telecommunication satellites. To operate all these satellites, use an electrical harness. The electrical harness includes all the cables present in the satellite and which does not carry any customer data. As part of this we are interested in optimizing the design of the electrical harness of satellites.
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Le routage dans les réseaux de capteurs multimédia / Routing in Wireless Multimedia Sensor NetworksZeghilet, Houda 08 December 2013 (has links)
Aujourd'hui, la prolifération de matériel peu coûteux tels que les caméras et les microphones capables de capturer du contenu multimédia de façon ubiquitaire a conduit à l'émergence des réseaux de capteurs sans fil multimédia/vidéo (RCSFM /RCSFV). En conséquence, un grand éventail d'applications peuvent être projetées dans de nombreux domaines de la vie de tous les jours. Par rapport aux réseaux de capteurs traditionnels (RCSF), les RCSFVs présentent des défis uniques principalement en raison de la grande quantité de données à capturer et à transmettre au-dessus d'un réseau contraint en ressources. Dans ce travail, nous avons d'abord proposé un protocole de routage hiérarchique appelé ELPC (Energy Level Passive Clustering) dont l'objectif principal est d'améliorer la durée de vie du réseau en présence de flux vidéo. Ceci est obtenu grâce à l'équilibrage des charges au moment de la construction de la topologie où le rôle de tête de groupe est alterné entre les noeuds candidats en fonction de leur niveau d'énergie. La deuxième contribution consiste en un protocole de routage multichemin qui prend les interférences inter-chemin en considération. Au lieu de supprimer complètement les interférences, notre protocole de routage multichemin tente de les minimiser en se basant sur l'ajout d'informations supplémentaires sur les noeuds voisins dans les messages de construction de la topologie. De plus, nous proposons un schéma de files d'attente à priorités multiples où l'influence des types de données. Les résultats des simulations montrent que l'utilisation de chemins moins interférents combinée à un régime de multipriorité permet une meilleure qualité vidéo / Nowadays, the proliferation of inexpensive hardware such as CMOS cameras and microphones that are able to ubiquitously capture multimedia content has led to the emergence of wireless multimedia/video sensor networks (WMSN/WVSN). As a consequence, a wide spectrum of applications can be projected in many areas and everyday life. Compared to traditional WSNs, WVSNs introduce unique challenges due mainly to the big amount of data to be captured and transmitted over a constrained network. In this work, we first propose a cluster-based (hierarchical) routing protocol called ELPC (Energy Level Passive Clustering) where the main objective is to enhance the network lifetime while handling video applications. This is achieved thanks to a load balancing feature where the role of clusterheads is alternated among candidate nodes depending on their energy level. The second contribution consists in a multipath routing protocol with interference awareness. Instead of completely suppressing interferences, our multipath routing protocol tries to minimize them through a simple algorithm without extra overhead. Multiple paths are built at once while minimizing their inter-path interferences thanks to some additional information on neighboring nodes piggybacked on the route request messages. In addition to interference awareness, we propose a multiqueue multipriority scheme where the influence of data type in a video is considered. Simulation results show that using less interfering paths combined to a multiqueue multipriority scheme allows for better video quality
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The Multi-product Location-Routing Problem with Pickup and Delivery / Problèmes de tournées de véhicules avec des contraintes de localisation et d'allocationRahmani, Younes 11 December 2015 (has links)
Dans les problèmes de localisation-routage classiques (LRP), il s'agit de combiner des décisions stratégiques liées aux choix des sites à ouvrir (centres de traitement) avec des décisions tactiques et opérationnelles liées à l'affectation des clients aux sites sélectionnés et a la confection des tournées associées. Cette thèse propose de nouveaux modèles de localisation-routage permettant de résoudre des problématiques issues de réseaux logistiques, devenus aujourd'hui de plus en plus complexes vu la nécessité de mutualisation de ressources pour intégrer des contraintes de développement durable et des prix de carburants qui semblent augmenter de manière irrémédiable. Plus précisément, trois aspects ont été intégrés pour généraliser les modèles LRP classiques de la littérature : 1) l'aspect pickup and delivery, 2) l'aspect multi-produits, et 3) la possibilité de visiter un ou plusieurs centres de traitement dans une tournée donnée. Nous avons étudié deux schémas logistiques, qui ont donné lieu à deux nouveaux modèles de localisation et de routage, le MPLRP-PD (LRP with multi-product and pickup and delivery), qui peut être vu comme une extension des problèmes de tournées de véhicules avec collecte et livraison, intégrant une décision tactique liée à la localisation des centres de traitement (noeud avec collecte et livraison) dans un réseau de distribution à un seul échelon, et le 2E-MPLRP-PD (Two-echelon LRP with multi-product and pickup and delivery) qui est une généralisation du LRP à deux échelons avec les contraintes citées plus-haut. Ces deux modèles ont été formalisés par des programmes linéaires en variables mixtes (MIP). Des techniques de résolution, basées sur des méthodes de type heuristique, clustering, métaheuristique, ont été proposées pour résoudre le MPLRP-PD et le 2E-MPLRP-PD. Les jeux d'essais de la littérature ont été généralisés pour tester et valider les algorithmes proposés / In the framework of Location-Routing Problem (LRP), the main idea is to combine strategic decisions related to the choice of processing centers with tactical and operational decisions related to the allocation of customers to selected processing centers and computing the associated routes. This thesis proposes a new location-routing model to solve problems which are coming from logistics networks, that became nowadays increasingly complex due to the need of resources sharing, in order to integrate the constraints of sustainable development and fuels price, which is increasing irreversibly. More precisely, three aspects have been integrated to generalize the classical LRP models already existed in the literature: 1) pickup and delivery aspect, 2) multi-product aspect, and 3) the possibility to use the processing centers as intermediate facilities in routes. We studied two logistics schemes gives us two new location-routing models: (i) MPLRP-PD (Multi-product LRP with pickup and delivery), which can be viewed as an extension of the vehicle routing problem with pick-up and delivery, including a tactical decision related to the location of processing centers (node with pick-up and delivery), and (ii) 2E-MPLRP-PD (Two-echelon multi-product LRP with pickup and delivery), which is a generalization of the two-echelon LRP. Both models were formalized by mixed integer linear programming (MIP). Solving techniques, based on heuristic methods, clustering approach and meta-heuristic techniques have been proposed to solve the MPLRP-PD and the 2E-MPLRP-PD. The benchmarks from the literature were generalized to test and to validate the proposed algorithms
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Context-aware hybrid data dissemination in vehicular networksUnknown Date (has links)
This work presents the development of the Context-Aware Hybrid Data Dissemination
protocol for vehicular networks. The importance of developing vehicular networking data
dissemination protocols is exemplified by the recent announcement by the U.S. Department of Transportation (DOT) National Highway Traffic Safety Administration (NHTSA) to enable vehicle-to-vehicle (V2V) communication technology. With emphasis on safety, other useful applications of V2V communication include but are not limited to traffic and routing, weather, construction and road hazard alerts, as well as advertisement and entertainment. The core of V2V communication relies on the efficient dispersion of relevant data through wireless broadcast protocols for these varied applications. The challenges of vehicular networks demand an adaptive broadcast protocol capable of handling diverse applications. This research work illustrates the design of a wireless broadcast protocol that is context-aware and adaptive to vehicular environments taking into consideration vehicle density, road topology, and type of data to be disseminated. The context-aware hybrid data dissemination scheme combines store-and-forward and multi-hop broadcasts, capitalizing on the strengths of both these categories and mitigates the weaknesses to deliver data with maximum efficiency to a widest possible reach. This protocol is designed to work in both urban and highway mobility models. The behavior and performance of the hybrid data dissemination scheme is studied by varying the broadcast zone radius, aggregation ratio, data message size and frequency of the broadcast messages. Optimal parameters are determined and the protocol is then formulated to become adaptive to node density by keeping the field size constant and increasing the number of nodes. Adding message priority levels to propagate safety messages faster and farther than non-safety related messages is the next context we add to our adaptive protocol. We dynamically
set the broadcast region to use multi-hop which has lower latency to propagate
safety-related messages. Extensive simulation results have been obtained using realistic vehicular network scenarios. Results show that Context-Aware Hybrid Data Dissemination Protocol benefits from the low latency characteristics of multi-hop broadcast and low bandwidth consumption of store-and-forward. The protocol is adaptive to both urban and highway mobility models. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection
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Planejamento de rotas dirigidas com base no problema de roteamento humanoRodrigues, Rafael Emidio Murata 30 August 2018 (has links)
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Previous issue date: 2018-08-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In our lives, we constantly move in streets and neighborhoods. In general, we consider
time and (or distance) when planning the route. However, their solutions may face
complex problems arising from the different possibilities of solutions. Similar to route
planning, the Vehicle Routing Problem was introduced by George B. Dantzig and John
H. Ramser in 1959 and consists of delivering gasoline to several fuel stations; at first
a mathematical proposal, later became an algorithmic approach, for planning of routes
of delivery of products in an optimized way (searching the "shortest path"). Although,
during the search of shortest path, they are limited to the use of the streets. In this
context emerges the Human Routing Problem, such an approach is not limited to
streets, but makes use of all possible paths, by vehicles and humans. Such a problem
can be observed in route planning at airports, museums and a supply chain company
that wants to optimize the route of delivery of its products and increase customer
satisfaction. Based on the Vehicle Routing Problem, the Human Routing Problem will
be proposed. Its problematic will be demonstrated in a prototype, capable of assisting
in the planning of human routes and three use cases. Ideas of Human Routing Problem
had inspiration in the collective foraging insects / Na nossa vida, nos locomovemos constantemente em ruas e bairros. Em geral,
consideramos o tempo e (ou a distância), ao planejar a rota. Contudo, suas soluções
podem enfrentar problemas complexos, decorrentes das diversas possibilidades de
soluções. Semelhante a planejamento de rotas, o Problema de Roteamento de
Veículos foi introduzido por George B. Dantzig, e John H. Ramser em 1959 e consiste
em entregar gasolina diversos postos de combustível; a princípio uma proposta
matemática, mais tarde tornou-se uma abordagem algorítmica, para planejamento de
rotas de entrega de produtos de forma otimizada (buscando o “menor caminho”).
Embora, durante a busca de menor caminho, limitam-se ao uso de ruas. Neste
contexto emerge o Problema de Roteamento Humano, tal abordagem não se limita a
ruas, mas faz uso de todos os caminhos possíveis, por veículos e humanos. Tal
problemática, pode ser observada nos planejamentos de rotas em aeroportos,
museus e em uma empresa de supply chain que deseja otimizar a rota de entrega dos
seus produtos, e aumentar a satisfação dos seus clientes. Tomando como base
central, o Problema de Roteamento de Veículos será proposto o Problema de
Roteamento Humano. Sua problemática, será demonstrado em um protótipo, capaz
de auxiliar no planejamento de rotas humanas e três casos de uso. As ideias do
Problema de Roteamento Humano tiveram inspiração no forrageamento dos insetos
coletivos
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Collision guided routing for ad hoc mobile wireless networksBa Surra, Shadi Saleh Ali January 2013 (has links)
Ad hoc mobile wireless networks are self-configuring infrastructureless networks of mobile devices connected via wireless links. Each device can send and receive data, but it should also forward traffic unrelated to its own use. All need to maintain their autonomy, and effectively preserve their resources (e.g. battery power). Moreover, they can leave the network at any time. Their intrinsic dynamicity and fault tolerance makes them suitable for applications, such as emergency response and disaster relief, when infrastructure is nonexistent or damaged due to natural disasters, such as earthquakes and flooding, as well as more mundane, day-to-day, uses where their flexibility would be advantageous. Routing is the fundamental research issue for such networks and refers to finding and maintaining routes between nodes. Moreover, it involves selecting the best route where many may be available. However, due to the freedom of movement of nodes, new routes need to be constantly recalculated. Most routing protocols use pure broadcasting to discover new routes, which takes up a substantial amount of bandwidth. Intelligent rebroadcasting reduces these overheads by calculating the usefulness of a rebroadcast, and the likelihood of message collisions. Unfortunately, this introduces latency and parts of the network may become unreachable. This dissertation presents a routing protocol that uses a new parallel and distributed guided broadcasting technique to reduce redundant broadcasting and to accelerate the path discovery process, while maintaining a high reachability ratio as well as keeping node energy consumption low. This broadcasting scheme is implemented in a Mobile Ad Hoc Network (MANET) and a Wireless Mesh Network (WMN). To reduce overheads further, a Zone based Routing with Parallel Collision Guided Broadcasting Protocol (ZCG) in MANET is introduced. This uses a one hop clustering algorithm that splits the network into zones led by reliable leaders that are mostly static and have plentiful battery resources. For WMN, a Social-aware Routing Protocol (SCG) is designed that draws upon social network theory to associate longstanding social ties between nodes, using their communication patterns to divide the network into conceptual social groups, which allows cluster members to protect each other from redundant broadcasts by using intelligent rebroadcasting. The performance characteristics of the new protocols are established through simulations that measure their behaviour and by comparing them to other well-known routing protocols, namely the: AODV, DSR, TORA and the OLSR, as appropriate, it emerges that two new protocols, the ZCG and SCG, perform better in certain conditions, with the latter doing consistently well under most circumstances.
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