Dissertations / Theses: 'Communication de véhicule à infrastructure'

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Plainchault, Patrick. "Sécurisation de la conduite par communication véhicule infrastructure à base de transpondeurs." Toulouse, INPT, 2005. http://ethesis.inp-toulouse.fr/archive/00000137/.

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Comment utiliser la communication entre les véhicules et l'infrastructure à base de transpondeurs pour sécuriser le déplacement automobile? Dans un premier temps, nous présentons un état de l'art des systèmes de localisation (LIDAR, RADAR, caméras vidéo, marqueur magnétique, GPS, gyroscope, et cartes embarquées. . . ), de communication (DAB, UMTS, DSRC, Bluetooth, WIFI, Infrarouge. . . ) et sur la technologie des transpondeurs. Puis nous rappelons les principes liés à l'étude d'un transpondeur sachant que ce système de communication s'appuie sur deux éléments principaux : 1) le lecteur et son antenne embarqués dans le véhicule 2 ) le transpondeur logé dans la bande de roulement composé d'antennes, d'un microcontrôleur et d'une mémoire. Enfin, nous présentons les résultats obtenus et quelques applications possibles : contrôle latéral et longitudinal, le calcul d'interdistance et la détection de circulation à contre sens
For many years, car manufacturers have been trying to ensure the safety of automobile movements. This thesis relates how a transponder based communication between vehicles and infrastructure can be used. In the first part overview of localisation systems (LIDAR, RADAR, video cameras, magnetic strip following, GPS, gyro platforms and cartography systems embedded in the vehicle), local communication (DAB, UMTS, DSRC, Bluetooth, WIFI, InfraRed,. . . ) and transponder technology are presented. Then it recalls the principles of transponder. This communication system consists of two main elements: 1) a base station with an antenna embedded in a vehicle, 2) a transponder, located in the tread including an antenna, a microcontroller for data processing and communication and a memory. Finally, also some results and applications: lateral and longitudinal positioning, inter distance calculation and detection of wrong way traffic are presented

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Hamidoun, Khadija. "Nouvelles architectures adaptatives de modulation et codage ULB selon la QoS requise pour la communication véhicule-infrastructure." Thesis, Valenciennes, 2016. http://www.theses.fr/2016VALE0004.

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Dans ce travail de thèse, nous proposons d'utiliser la technologie ULB pour établir un nouveau système de communication haut débit Radio Impulsionnelle (IR-ULB), basé sur un nouveau schéma de modulation nommé M-OAM (M-Orthogonal Amplitude Modulation) et les formes d'ondes orthogonales MGF (Modified Gegenbaeur Function). Ce système est dédié aux applications sans fil à courte portée, notamment les communications multimédia et le transport intelligent (ITS). Les modulations M-OAM proposées, sont évaluées sous le canal AWGN et les canaux ULB à trajets multiples à savoir IEEE.802.15.3a et IEEE.802.15.4a. Les résultats de simulation montrent que la performance du système proposé, en terme de taux d'erreur binaire (BER), est du même ordre que celle des modulations ULB traditionnelles. En outre, les modulations M-OAM offrent un très haut débit de données avec une faible complexité d'implémentation. En effet, la conception d'un tel système doit certes fournir un très haut débit mais aussi servir un grand nombre d'utilisateurs simultanément avec une bonne qualité de service. Dans cette optique, une nouvelle technique d'accès multiple DS-MGF-OAM est proposée. Ce système multi-utilisateur fait usage de la technique DS-ULB et l'orthogonalité des impulsions MGF pour permettre une communication efficace avec un nombre maximal d'utilisateurs. Néanmoins, l'effet de trajets multiples réduit la qualité de la transmission. Ainsi, la contribution de deux architectures de réception dans l'amélioration des performances est étudiée, à savoir le récepteur RAKE et l'égaliseur MMSE (Minimum Mean Square Error). Cette étude montre que le système de communication M-OAM offre de bonnes performances en terme de qualité de services (QoS). Après l'étape de simulation, les résultats expérimentaux des systèmes proposés dans les environnements réelles sont analysés et discutés. Dans la dernière partie de ce document, nous avons réalisé un prototype de traitement en temps réel sur une plateforme FPGA, offrant des temps de calcul à 3GHz grâce à des algorithmes parallélisables sur des architectures re-configurables
In this thesis, we propose to use the UWB technology to establish a new communications system Impulse Radio (IR-UWB), based on a new modulation scheme called M-OAM (Orthogonal M-Amplitude Modulation) and orthogonal waveforms MGF (Modified Gegenbauer Function). This system is dedicated to the short-range wireless applications, especially multimedia communications and intelligent transportation (ITS). The proposed modulations M-OAM, are evaluated under the AWGN channel and UWB multipath channel namely IEEE.802.15.3a and IEEE.802.15.4a. Simulation results show that the performance of the proposed system in terms of bit error rate (BER) is the same as that of traditional UWB modulations. In addition, M-OAM modulations offer the highest data rate with low complexity of implementation. Indeed, the design of a such system should certainly provide a very high speed but also serve a large number of concurrent users with good quality of service. In this context, a new multiple access technique DS-MGF-OAM is proposed. This multi-user system makes use of the DS-UWB technology and orthogonal pulses MGF to enable effective communication with a maximum number of users. However, the multi-path effect reduces the quality of the transmission. Thus, the contribution of two receiver architectures in performance improvement is studied, namely the RAKE receiver and MMSE (Minimum Mean Square Error) equalizer. This study shows that the M-OAM communication system offers good performance in terms of quality of service (QoS). Following the simulation step, the experimental results of the proposed systems in real environments are analyzed and discussed. In the last part of this document, we performed a real-time protoptype on an FPGA platform, offering calculation time of 3GHz through parallelizable algorithms on reconfigurable architectures

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Randriamasy, Malalatiana. "Localisation et transmissions sécurisées pour la communication Véhicule à Infrastructure (V2I) : Application au service de télépéage ITS-G5." Thesis, Normandie, 2019. http://www.theses.fr/2019NORMR011/document.

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La localisation précise des véhicules et la sécurité des échanges sont deux grands axes qui font la fiabilité des services fournis dans les systèmes de transport intelligent. Ces dernières années, elles font l’objet de nombreux projets de recherche pour des champs d’application divers. Dans cette thèse, le contexte d’application est la réalisation d’un service de télépéage utilisant la technologie ITS-G5. Cette technologie de communication sans-fil permet dans un premier temps le partage des informations de sécurité routière entre les véhicules (V2V), le véhicule et l’infrastructure (V2I). Dans cette thèse, on propose une architecture permettant d’échanger des transactions de télépéage utilisant les équipements communicants en ITS-G5 embarqués dans les véhicules connectés et les unités bord de route (UBR) de l’infrastructure. Les problématiques de nos travaux de recherche se concentrent sur la méthode de localisation des véhicules ayant effectué la transaction afin de pouvoir la valider et sur la sécurité de l’architecture proposée pour assurer l’échange de cette transaction. Afin de bien localiser les véhicules lors du passage au péage, notre approche propose la compréhension de la cinématique du véhicule par une modélisation adéquate à partir des données recueillies dans les messages coopératifs (CAM : Cooperative Awareness Message) en approche du péage. Cela améliorera les informations de géolocalisation déjà présentes. Notre objectif est d’arriver à une précision de moins d’un mètre pour distinguer 2 véhicules adjacents. D’autre part, le protocole de sécurité proposé permet d’assurer l’authentification des équipements participant à l’échange et à la validation de la transaction, l’intégrité des données échangées ainsi que la confidentialité des échanges compte tenu du contexte de communication sans-fil et de la sensibilité des données échangées. Une preuve de concept de la solution de télépéage utilisant la technologie ITS-G5 est développée et intègre nos deux contributions
The precise localization of vehicles and the security of communication are requirements that make almost of the services provided in intelligent transport systems (ITS) more reliable. In recent years, they have been the subject of numerous research projects for various fields of application. In this thesis, the context is the development of an electronic toll service using the ITS-G5 technology. This wireless communication technology initially allows the sharing of traffic safety information between vehicles (V2V), vehicle and infrastructure (V2I). In our work, we propose a tolling application using equipment operating in ITS-G5 embedded in the connected vehicles and roadside units. For this, ensuring both precise geolocation of the vehicles and security of communication are required to validate the transaction.In order to properly locate the vehicles during the toll crossing, our approach is based on the understanding of the kinematics of the vehicle through a suitable modeling from the data collected in the cooperative messages (called CAM: Cooperative Awareness Message). This approach aims to improve the geolocation information already present in the message. Our goal is to achieve vehicle localization with an accuracy lower than one meter to distinguish two adjacent vehicles. On the other hand, the proposed tolling protocol ensures the authentication of the equipment or entities involved in the exchange and the validation of the transaction, the integrity of the transmitted data as well as the confidentiality of the communication. In this way, we take into account the context of the wireless communication and the sensitivity of the exchanged data. Our two contributions are integrated in the implemented Proof of Concept of the tolling application using the ITS-G5 technology

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Yan, Fei. "Contribution à la modélisation et à la régulation du trafic aux intersections : intégration des communications Vehicule-Infrastructure." Phd thesis, Université de Technologie de Belfort-Montbeliard, 2012. http://tel.archives-ouvertes.fr/tel-00720641.

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Dans ce mémoire de thèse, nous avons étudié le problème de régulation du trafic en considérant les nouvelles technologies dans le cadre des Systèmes de Transport Intelligent (STI). Une nouvelle stratégie de contrôle est introduite afin d'exploiter le potentiel des infrastructures de la circulation à un niveau maximum. Plus précisément, basée sur la technologie VII " Intégration Véhicule-Infrastructure ", l'infrastructure routière aux carrefours (considérée aussi comme contrôleur) peut communiquer avec les véhicules autonomes qui arrivent à un carrefour de manière continue. Les données importantes sur les véhicules telles que la vitesse, la position et la destination sont alors reçues par des capteurs avancés et envoyées au contrôleur en temps réel. Par conséquent, il est possible d'élaborer une stratégie de contrôle du trafic en considérant chaque véhicule comme une entité indépendante. En d'autres termes, le droit de passage est attribué à chaque véhicule en fonction de son état et en fonction de l'état global du trafic au carrefour. Seuls les véhicules qui ont reçu le droit de passage peuvent traverser le carrefour. Le contrôle du trafic au niveau d'un carrefour vise donc à déterminer les séquences de passage des véhicules, c'est-à-dire les séquences de distribution des droits de passage.Cependant, la plus grande difficulté pour appliquer cette nouvelle stratégie est la contradiction entre l'optimisation des séquences de passages des véhicules et la complexité temporelle. Pour résoudre cette contradiction, nous avons d'abord formulé mathématiquement la problématique de régulation et nous avons ensuite étudié sa complexité. Nous avons prouvé dans un premier temps que le problème de régulation du trafic formulé à l'intersection isolée est NP-hard sous certaines conditions (nombre arbitraire de groupes de flux compatibles GFC,...) et ceci en se basant sur la réduction au problème de 3-Partition. Dans un deuxième temps, nous avons appliqué les méthodes de résolutions exactes sur un carrefour isolé pour proposer des algorithmes exacts (Branch and Bound et Programmation dynamique) permettant de trouver une séquence de passage optimale. Plusieurs propriétés du problème ont été introduites et prouvées et ceci afin qu'elles soient exploitées par ces algorithmes. Ces propriétés ont pour objectif de réduire considérablement l'espace de recherche et par conséquent le temps d'exécution de ces algorithmes exacts.Par ailleurs, nous n'avons pas limité nos recherches sur des carrefours isolées mais nous avons appliqué l'approche de contrôle proposée sur un réseau de carrefours tout en considérant un seul contrôleur. Cependant, un algorithme exact appliqué sur plusieurs carrefours ne peut pas être assez rapide surtout lorsqu'on a besoin de communiquer presque instantanément des informations aux véhicules (en temps réel). Nous avons proposé donc des méthodes de résolutions approchées afin de trouver en un temps raisonnable une séquence de passage satisfaisante pour chaque carrefour. Ces algorithmes (Algorithmes génétiques) ont en effet, besoin de moins de temps de calcul tout en assurant une bonne qualité de solution.Enfin, nous illustrons la mise en œuvre des déférentes approches proposées à travers des résultats de simulation afin d'évaluer leurs performances.

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Dahmouni, Nor El Islam. "Caractérisation multidimensionnelle du canal de propagation et contribution de l'intelligence artificielle à la classification des scénarios de propagation pour les communications véhiculaires." Electronic Thesis or Diss., Université de Lille (2022-....), 2024. http://www.theses.fr/2024ULILN014.

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Au cours des dernières années, les réseaux mobiles ont considérablementamélioré leurs performances, notamment avec l'avènement de la 5G offrant desdébits bien plus élevés que ceux de la 4G. Ces avancées sont attribuables aux progrèstechnologiques dans divers domaines tels que les systèmes antennaires intégrés et lescomposants électroniques alliant rapidité et faible consommation. La 5G inaugureune ère de services diversifiés incluant l'Internet des Objets (IoT) et lescommunications véhiculaires, de Véhicule à Infrastructure (V2I) et de Véhicule àVéhicule (V2V). Dans ce contexte, la 5G propose une classe de communication(URLLC) offrant une latence ultra-faible et une fiabilité accrue.Pour accroître les performances de la 5G en termes d'efficacité spectrale, denombre d'utilisateurs et de temps de latence, des recherches ont débuté en octobre2022 dans le cadre de la Release 18 du 3GPP avec, pour objectif, d'explorer lepotentiel que pourrait apporter l'Intelligence Artificielle (IA) et les modèlesd'apprentissage type Machine Learning (ML) dans l'interface radio. Ce projet viseainsi à optimiser la technique d'estimation du canal et d'allocation des ressources,ainsi que la précision de positionnement. Le point commun à ces 3 objectifs est lecanal de propagation.Cette thèse se focalise sur les liens V2I dans les milieux suburbains et dans lestunnels.L'originalité des travaux réside dans i) la caractérisation multidimensionnelle(temps-espace-fréquence-polarisation) du canal en milieu suburbain et tunnel grâceaux nombreuses campagnes de mesures effectuées avec la sondeur de canalMaMIMOSA, ii) l'analyse de la variabilité temporelle et spatiale du canal MIMO, iii)création d'une base de données des paramètres du canal et iv) l'adaptation desmodèles d'apprentissage automatique pour la détection des types de scénario depropagation (LOS/NLOS). Notons que l'état de l'art ne concerne que les milieuxindoor ou l'environnement urbain avec des liens satellitaires.Ces travaux ont permis de constituer une base de données expérimentalesobtenues à partir de l'exploitation de mesures faites en site suburbain et en tunnel, etrespectivement sur ∼100k et ∼200k matrices de canal V2I. Le modèle ML pour laclassification des scénarios de propagation, soit en visibilité directe (LOS), soit sansvisibilité directe (NLOS), affiche des performances de prédiction de 97,9%
Over the past few years, mobile networks have significantly improved theirperformance, especially with the advent of 5G offering much higher data rate than4G. These advancements are attributable to technological progress in various areassuch as integrated antenna systems and electronic components that combine highresponse time with low power consumption. 5G ushers in an era of diversifiedservices including the Internet of Things (IoT) and vehicular communications, fromVehicle-to-Infrastructure (V2I) and Vehicle-to-Vehicle (V2V). In this context, 5Gintroduces a class of communication (URLLC) offering ultra-low latency andincreased reliability.To enhance the performance of 5G in terms of spectral efficiency, the number ofusers, and latency time, research began in October 2022 as part of the 3GPP Release18 with the goal of exploring the potential that Artificial Intelligence (AI) andMachine Learning (ML) models could bring to the radio interface. This project aimsto optimize the channel estimation technique and resource allocation, as well aspositioning accuracy.As part of these studies, this thesis focuses on V2I links in suburban environmentsand tunnels. Its objective is to create an experimental database of the most relevantparameters of the propagation channel, which will then allow for the training of MLmodels. On this point, the state of the art only concerns indoor environments or theurban environment with satellite links.The originality of the work lies in : i) measurement campaigns carried out inrealistic environments and scenarios, ii) the multidimensional characterization(time-space-frequency-polarization) of the propagation channel considering MIMO(Multiple Input Multiple Output-MIMO) antenna networks at the transmission andreception, iii) the analysis of the temporal and spatial variability of MIMO channels,and, iv) the adaptation of machine learning models for the classification ofpropagation scenarios.These works have led to the creation of an experimental database obtained fromthe exploitation of measurements made in suburban sites and tunnels, andrespectively on approximately 100k and 200k V2I channel matrices. The ML modelfor the classification of propagation scenarios, either in line of sight (LOS) or Non lineof sight (NLOS), shows prediction performances of 97.9% ; the number of points inLOS and NLOS is balanced to feed the model

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Belmekki, Sabrine. "Multi-level risk and collective perception for high quality of service automated mobility in a highly dynamic V2X connected environment." Electronic Thesis or Diss., Université de Lille (2022-....), 2023. http://www.theses.fr/2023ULILB009.

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Les technologies des véhicules automatisés se développent rapidement et sont deplus en plus présentes dans notre vie quotidienne pour créer des systèmes de trans-port entièrement connectés. Les constructeurs automobiles équipent à présent lesderniers modèles de véhicules de certaines fonctions d'aide à la conduite. Les avan-tages potentiels de ces véhicules incluent la réduction des collisions, l'atténuationdes embouteillages, la réduction de la consommation de carburant, et une flexibil-ité accrue pour les personnes qui n'ont pas accès aux transports. Pour permettrel'automatisation de ces fonctions, il est nécessaire de disposer de données relativesà la détection d'obstacles, la configuration de la route et l'environnement.L'objectif de cette étude est d'examiner l'adaptabilité et l'aptitude du modèle decommunication de la feuille de branche de chaîne (Chain Branch Leaf-CBL) dansles systèmes coopératifs et d'examiner son impact sur les réponses de la circula-tion. De plus, la recherche vise à déterminer le rôle des unités en bord de route etl'efficacité de la perception à plusieurs niveaux dans la prévention des risques. Lebut ultime de cette recherche est d'améliorer la communication et la collaborationentre les véhicules conventionnels et autonomes, ce qui se traduira par une circu-lation plus sûre et plus efficace.Dans cette thèse, nous avons étudié l'utilisation d'une architecture et des stratégiesde communication adaptées pour améliorer la qualité de service en utilisant les in-formations des véhicules entourant l'égo véhicule. Nous avons proposé le conceptde Chain Branch Leaf-Gateway Clustering pour réaliser une topologie optimaled'unité de bord de route-UBR assurant une haute qualité et continuité de service.Nous avons également étudié la perception multi-niveau pour estimer les risquesde collision multi-niveau (local, local étendu, branche étendu et global).Par la suite, nous utilisons les métriques (Time to collision (TTC), Time TimeHeadway (TH), Distance of Gruyer (DG), Risk estimator with uncertainties andmultidimensional model (RIMUM)). Pour estimer les quatre risques de collision(étendus) dans des conditions optimales avec une localisation et une perceptionparfaites, et la situation d'incertitude de la perception avec une localisation par-faite. Les résultats montrent que les risques étendus permettent une meilleureanticipation de la collision que le risque local.De plus, nous avons développé une nouvelle version étendue du modèle Chainbranch leaf-Gateway (CBL-G), qui s'avère plus efficace en termes de couverture.L'architecture hiérarchique du modèle nous permet de calculer les risques de col-lision avec une plus grande précision. La classification en différents niveaux derisque nous permet de identifier les situations potentiellement dangereuses. Dans nos projets de recherche futurs, nous planifions d'étudier d'autres situationstelles que les intersections routières, les sorties et les entrées d'autoroutes ainsique les ronds-points. De plus, nous aimerions explorer les cas dans lesquels il est impossible de localiser les nœuds à travers la chaîne en passant à travers des tun-nels et élaborer des indicateurs de risque qui explorent tous les composants clés(véhicule ego, conducteur, obstacle, route et environnement)
The use of automated vehicle (AV) technologies such as self-driving cars is becoming more prevalent in daily life. These technologies aim to create fully- connectedtransportation systems, still there are concerns that remain unaddressed. Studieshave shown that AVs can reduce collisions, ease traffic congestion, and providetransportation options for those who lack access. Yet, car manufacturers havealready implemented certain automated features in their vehicles. One importantaspect of AVs is improving communication between the vehicle and roadside.The objective of this study is to investigate the adaptability and suitability of theChain branch leaf (CBL) communication model in cooperative systems to exam-ine its impact on traffic responses. Additionally, the research aims to determinethe role of Roadside Units and the effectiveness of multi-level perception in riskmitigation. The ultimate goal of this research is to improve communication andcollaboration between autonomous vehicles leading to safer and more efficient traf-fic flow.This thesis focuses on the estimation of obstacle attributes, the road, and theego-vehicle to improve the quality of service on the road through communication,localization, and perception functions. We propose architectures and communica-tion strategies that will take into account the information of surrounding vehiclesto optimize coverage and estimate collision risk at different levels including local,extended local, extended branch, and global.Subsequently, we use the most relevant metrics (Time to Collision (TTC), TimeHeadway (TH), Distance of Gruyer (DG), RISK (R), Risk estimator with Uncer-tainties and Multidimensional model (RIMUM)), to estimate the four (extended)collision risks. In optimal conditions first with perfect location and perception,and then the uncertainty scenario of perception with perfect location. Resultsshow that the extended risks allow better anticipation of the collision than thelocal risk.Furthermore, we have developed a new extended version of the Chain branch leaf-Gateway (CBL-G) model, which proves to be more efficient in terms of coverage.The hierarchical architecture of the model allows us to calculate collision riskswith greater accuracy. The different levels of risk allow us to identify potentiallydangerous situations earlier, which is considered to be very relevant for incidentprevention.In our future research projects, we plan to study other situations such as roadintersections, highway exits, and entrances, as well as roundabouts. Additionally,we would also like to explore cases where we are unable to locate nodes throughthe chain (such as passing through tunnels). And elaborate risk indicators thatexplore all key components (ego vehicle, driver, obstacle, road, and environment)

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Grégoire, Girard Pierre-Luc. "Communication inter-véhicules et route-à-véhicule. Apprentissage de la communication inter-véhicules." Thesis, Université Laval, 2008. http://www.theses.ulaval.ca/2008/25810/25810.pdf.

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L'industrie des transports est un acteur important de l'économie mondiale. Des millions d'emplois sont touchés de près ou de loin par cette industrie. De plus, le nombre de véhicules sur terre ne cesse d'augmenter et il est rendu courant dans plusieurs pays industrialisés d'avoir plus d'une voiture par famille. Tout cela entraîne également son lot de problèmes, notamment au niveau de la sécurité routière et de la pollution. Depuis des décennies, des compagnies privées et des organisations publiques se penchent sur ces problèmes. Ils innovent constamment en améliorant les véhicules et les infrastructures du réseau routier. Les voitures ne sont pas seulement de plus en plus sécuritaires mais aussi de plus en plus confortables et conviviales. Cependant, la plupart des systèmes intelligents présents dans les voitures acquièrent de l'information grâce aux capteurs. Ceux-ci sont limités et certaines données ne peuvent être accessibles aux capteurs. La solution repose donc sur l'utilisation de la communication sans fil pour échanger des informations entre les véhicules et entre les infrastructures et les véhicules. Le sujet de cette maîtrise porte sur la communication inter-véhicules et route-à-véhicule. Elle se divise en deux parties. Tout d'abord, dans le cadre du projet AUTO21 au laboratoire DAMAS, un protocole de communication inter-véhicules doit être développé pour implanter un système de régulateur de vitesse collaboratif et adaptatif (« Collaborative Adaptative Cruise Control », CACC). La théorie multi-agents et l'apprentissage par renforcement sont utilisés pour apprendre une politique de communication optimale. La deuxième partie porte sur la communication route-à-véhicule appliquée au problème d'optimisation des feux de signalisation. Deux approches multiagents sont utilisées pour optimiser la gestion des feux. Les agents placés aux intersections reçoivent de l'information relative au trafic grâce à la communication route-à-véhicule et tentent d'adopter une politique de contrôle optimale.

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Grégoire-Girard, Pierre-Luc. "Communication inter-véhicules et route-à-véhicule : apprentissage de la communication inter-véhicules." Master's thesis, Université Laval, 2008. http://hdl.handle.net/20.500.11794/20541.

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L'industrie des transports est un acteur important de l'économie mondiale. Des millions d'emplois sont touchés de près ou de loin par cette industrie. De plus, le nombre de véhicules sur terre ne cesse d'augmenter et il est rendu courant dans plusieurs pays industrialisés d'avoir plus d'une voiture par famille. Tout cela entraîne également son lot de problèmes, notamment au niveau de la sécurité routière et de la pollution. Depuis des décennies, des compagnies privées et des organisations publiques se penchent sur ces problèmes. Ils innovent constamment en améliorant les véhicules et les infrastructures du réseau routier. Les voitures ne sont pas seulement de plus en plus sécuritaires mais aussi de plus en plus confortables et conviviales. Cependant, la plupart des systèmes intelligents présents dans les voitures acquièrent de l'information grâce aux capteurs. Ceux-ci sont limités et certaines données ne peuvent être accessibles aux capteurs. La solution repose donc sur l'utilisation de la communication sans fil pour échanger des informations entre les véhicules et entre les infrastructures et les véhicules. Le sujet de cette maîtrise porte sur la communication inter-véhicules et route-à-véhicule. Elle se divise en deux parties. Tout d'abord, dans le cadre du projet AUTO21 au laboratoire DAMAS, un protocole de communication inter-véhicules doit être développé pour implanter un système de régulateur de vitesse collaboratif et adaptatif (" Collaborative Adaptative Cruise Control ", CACC). La théorie multi-agents et l'apprentissage par renforcement sont utilisés pour apprendre une politique de communication optimale. La deuxième partie porte sur la communication route-à-véhicule appliquée au problème d'optimisation des feux de signalisation. Deux approches multiagents sont utilisées pour optimiser la gestion des feux. Les agents placés aux intersections reçoivent de l'information relative au trafic grâce à la communication route-à-véhicule et tentent d'adopter une politique de contrôle optimale.

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Zhang, Shu. "Communication infrastructure supporting real-time applications." Aachen Shaker, 2007. http://d-nb.info/988385538/04.

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Zhang, Shu. "Communication infrastructure supporting real-time applications /." Aachen : Shaker, 2008. http://www.gbv.de/dms/ilmenau/toc/565672754.PDF.

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Ayaida, Marwane. "Contribution aux communications intra-véhicule et inter-véhicules." Thesis, Reims, 2012. http://www.theses.fr/2012REIMS016/document.

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Les véhicules modernes sont équipés de périphériques permettant d'automatiser des tâches (changement de vitesse de transmission, régulation de vitesse, etc.) ou de fournir des services à l'utilisateur (aide à la conduite, détection d'obstacles, etc.). Les communications entre les véhicules permettent d'élargir ces services grâce à la collaboration de plusieurs véhicules (prévention des accidents, gestion du trafic routier, etc.). La multiplication de ces périphériques, de leurs interfaces et protocoles rend l'échange de données plus complexe. Par ailleurs, la communication inter- véhicules est plus contraignante à cause de la haute mobilité des véhicules. Dans cette thèse, nous proposons la conception d'un canal de communication Connect to All (C2A) qui permet d'assurer l'interopérabilité entre les périphériques embarqués dans un véhicule. En effet, il détecte la connexion à chaud d'un équipement, le reconnaît et lui permet d'échanger des données avec les autres périphériques connectés. La conception du canal commence par la modélisation de ce canal en utilisant deux techniques différentes (l'outil de modélisation et de vérification UPPAAL et le Langage de Description et de Spécification (LDS)). La vérification des modèles proposés a pour but de valider le fonctionnement. Ensuite, nous détaillons une implémentation réelle du canal sur une carte embarquée qui vise à démontrer la faisabilité du concept d'interopérabilité de C2A.Nous avons aussi étudié les effets de la mobilité dans la communication inter-véhiculaires grâce à une approche hybride mixant le routage et un service de localisation. Cette approche offre un mécanisme qui permet de réduire les coûts de la localisation des véhicules tout en augmentant les performances de routage. En plus, nous comparons deux applications de cette approche : Hybrid Routing and Grid Location Service (HRGLS) et Hybrid Routing and Hierarchical Location Service (HRHLS) avec des approches originelles pour démontrer la valeur ajoutée. Cette approche est enrichie avec un algorithme de prédiction de mobilité. Ce dernier permet de mieux cerner le déplacement des véhicules en les estimant. De même, l'approche hybride avec prédiction de mobilité Predictive Hybrid Routing and Hierarchical Location Service (PHRHLS) est comparée à HRHLS et l'approche originelle afin de révéler les bénéfices de la prédiction de mobilité
Modern vehicles are equipped with various devices that aim to automate tasks (shift transmission, cruise control, etc.) or to provide services to the user (driver assistance, obstacle detection, etc.). Communications between vehicles help to expand these services through the collaboration of several vehicles (accident prevention, traffic management, etc.). The proliferation of these devices, their interfaces and protocols makes the data exchange more complex. In addition, inter-vehicle communication is more restrictive because of the vehicles' high mobility.In this work, we propose the design of a communication channel Connect to All (C2A) that ensures the interoperability between embedded devices in a vehicle. In fact, it detects the equipment connection, recognizes it and allows it to exchange data with other devices. The channel design starts by the modelling step using two different techniques (the model checker tool UPPAAL and the Specification and Description Language (SDL). Then, we validate the designed models. We also detail a concrete implementation of the channel on an embedded chip that aims to show the C2A interoperability concept feasibility.We also studied the mobility effects in the inter-vehicular communication through a hybrid approach mixing routing and location-based service. This approach provides a mechanism to reduce vehicle-tracking costs while increasing routing performances. Moreover, we compare two applications of this approach: Hybrid Routing and Grid Location Service (HRGLS) and Hybrid Routing and Hierarchical Location Service (HRHLS) with classical approaches to prove the added value. Then, this approach is improved with a mobility prediction algorithm. The latter allows a better understanding of the vehicle movements by estimating them. Similarly, the hybrid approach with mobility prediction Predictive Hybrid Routing and Hierarchical Location Service (PHRHLS) is compared with the basic approach and HRHLS in order to show the mobility prediction advantages

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12

Pop, Septimia-Cristina. "Conception et développement d'une infrastructure de communication collaborative." Phd thesis, Grenoble INPG, 2005. http://tel.archives-ouvertes.fr/tel-00081666.

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Ces dernières années le déploiement de réseaux sans fil a changé le paysage des réseaux informatiques. Grâce à l'évolution de la technologie informatique un utilisateur peut étendre son environnement de travail habituel en bénéficiant de la connectivité réseau accrue. La gestion souple de la mobilité lui permet d'accéder à différents environnements de collaboration. Cette thèse considère le problème de partage de l'affichage d'applications dans les conditions de la diversification des contextes de collaboration. Étant donné le déploiement du système de fenêtrage X et du système d'affichage à distance VNC, nous les avons choisi comme base pour notre travail. D'une part, nous avons conçu un système de partage d'applications X qui gagne en flexibilité par son interface du contrôle d'évènements d'entrée. Le système repose sur un multiplexeur de flots X conçu comme un service actif qui peut être chargé dynamiquement sur une plate-forme générique. D'autre part, nous avons transformé le système VNC en un système coopératif flexible. Le nouveau système est construit autour d'un proxy dynamiquement contrôlé à distance. Le proxy peut être programmé pour gérer différentes sessions de collaboration. Chaque session de collaboration peut utiliser des flots de données de VNC multiples. L'ouverture du système vers des politiques de contrôle d'évènements entrée permet l'adaptation au contexte de coopération. Finalement nous présentons des nouvelles perspectives concernant les possibilités de collaboration assistée par la technologie informatique dans un réseau informatique quelconque.

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Zhang, Shu [Verfasser]. "Communication Infrastructure Supporting Real-Time Applications / Shu Zhang." Aachen : Shaker, 2008. http://d-nb.info/1162790318/34.

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De, Stefano Timothy. "Information communication technology, broadband infrastructure and firm performance." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/37298/.

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Chitedze, Zimani. "Mobility management for Wi-Fi infrastructure and mesh networks." University of the Western Cape, 2012. http://hdl.handle.net/11394/2960.

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Magister Scientiae - MSc
This thesis shows that mobility management protocols for infrastructure Internet may be used in a wireless mesh network environment. In this research Mobile IPv6 and Fast Handover for Hierarchical Mobile IPv6 are successfully implemented in a wireless mesh network environment. Two experiments were carried out: vertical and horizontal handover simulations. Vertical handover simulation involved a heterogeneous wireless environment comprising both wireless local area and wireless mesh networks. An OPNET Mobile IPv6 model was used to simulate the vertical handover experiment. Horizontal handover simulation involved Mobile IPv6 and Fast Handover for Hierarchical Mobile IPv6 applied in ns2 wireless mesh network. The vertical handover results show that MIPv6 is able to manage vertical handover between wireless local area and wireless mesh network. The horizontal handover results illustrate that in mesh networks, Fast Handover for Hierarchical Mobile IPv6's performance is superior to Mobile IPv6. Fast Handover for Hierarchical Mobile IPv6 generates more throughput and less delay than Mobile IPv6. Furthermore, Fast Handover for Hierarchical Mobile IPv6 drops less data packets than Mobile IPv6. The simulations indicate that even though there are multi-hop communications in wireless mesh networks, the performance of the multi-hop routing may not play a big role in the handover performance. This is so because the mesh routers are mostly static and the multi-hop routes are readily available. Thus, the total handover delay is not affected too much by the WMN hops in the paths for signaling message transmission.
South Africa

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16

Kanyaboina, Rajanikanth. "E-staurant a software infrastructure for restaurant management /." [Gainesville, Fla.] : University of Florida, 2001. http://etd.fcla.edu/etd/uf/2001/anp1605/finaldoc.pdf.

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Thesis (M.S.)--University of Florida, 2001.
Title from first page of PDF file. Document formatted into pages; contains x, 65 p.; also contains graphics. Vita. Includes bibliographical references (p. 63-64).

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Nordstedt, David Roger. "MicroJini a service discovery and delivery infrastructure for pervasive computing /." [Gainesville, Fla.] : University of Florida, 2001. http://purl.fcla.edu/fcla/etd/UFE0000338.

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Thesis (M.E.)--University of Florida, 2001.
Title from title page of source document. Document formatted into pages; contains xi, 76 p.; also contains graphics. Includes vita. Includes bibliographical references.

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18

Schafrik, Steven J. "Underground Wireless Mesh Communication Infrastructure Design Prediction and Optimization." Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/19365.

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In an underground coal mine, the measure of a communication system is the coverage area it can provide at a quality that ensures a miner can communicate with other miners in and out of the mine during normal and emergency operations. The coverage area of a wireless mesh communication system can be calculated using the tool, COMMs, developed and discussed in this document. This tool can also be used to explore emergency operations, or operations where the mesh infrastructure is degraded or destroyed. Most often, the communication system is also capable of transmitting data from sensors including a set of sensors, such as Radio Frequency Identification readers, described as the tracking system.
An underground tracking system is described as a system that calculates a location in a useful coordinate when a tracked device is underground. The tracked device is a representative of a miner, group of miners or equipment, depending on state law and the mine\'s deployment. The actual location of the miner or equipment being tracked is the Ground Truth Position (GTP) and the tracking system\'s representation in the same coordinate system at the same time is the Tracking System Position (TSP). In an excellent tracking system the actual location, GTP, and TSP will be very close to each other. This work also develops a set of calculated metrics that describe tracking system performance.
The Tracking Coverage Area metric refers to the area within the mine that the tracking system either actively measures a tracked device\'s location or infers it based on the spatial limitations of the mine and information other than active measurements. Average Accuracy is the arithmetic mean of a set of distances from the TSP to the GTP associated with a tracking system. The Average Cluster Radius metric is the average distance a set of TSPs are from their center point, which is determined by the average location of a TSP relative to the GTP. A 90% Confidence Distance is the distance from a tracked device\'s actual location (i.e., GTP) that is greater than 90% of the collected distance from GTP to TSP magnitudes ("90th percentile").
Regulatory guidelines in the United States currently define different tracking qualities at locations in the mine. These can be classified in location categories of Working Face, Strategic Areas, and Escapeways and Travel-ways.
All direct paths via escapeway or travel-way from the mine portal to the working face should be simplified into a one-dimensional path that is subdivided by the three regulatory categories. Each of these subdivisions should be described using the metrics defined above.
These metrics can be predicted using COMMs for a tracking system that is utilizing an underground wireless mesh system that uses Received Signal Strength Indicators (RSSI) to calculate the TSP. Because the tracking system\'s algorithm to convert RSSI into a TSP is proprietary to the manufacturer, in order to develop predictions the engineer must collaborate with the manufacturer. In this document, the predictions and calculations were obtained in conjunction with the manufacturer and proved to be accurate describing the tracking system that was designed and tested.
Ph. D.

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19

Hestell, Filip, and Felix Zuber. "Designing an Efficient Communication Infrastructure for the Power Grid." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-254231.

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A step towards renewable energy is the smart grid, i.e. a power grid that is capable of smart distribution and load managing. This requires the participating components, nodes, to be able to communicate in a reliable fashion. The work of this project was to take on a mathematical approach by using the study of network science, which resulted in the design of a communication network topology for the power grid. The main focus of this undertaking was to quantify how a node in the power grid reacts to change in power flow, which was denoted as its sensitivity. By using Matpower, a tool programmed in Matlab, and our developed method, a communication network was able to be designed using a threshold algorithm. This method worked for the small scale power grids considered in this project, but a different approach might be needed for larger grids.

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Mahdy, Ahmed M. "A broadband infrastructure for ad hoc networks with optical wireless." [Lincoln, Neb. : University of Nebraska-Lincoln], 2005. http://0-www.unl.edu.library.unl.edu/libr/Dissertations/2005/MahdyDis.pdf.

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Chu, Carlson. "Development of broadband information infrastructure in Hong Kong /." Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B19876804.

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Plascencia, Cruz Luis Emmanuel. "Contrôle de la communication par lumière visible dans un environnement de véhicule de peloton." Electronic Thesis or Diss., université Paris-Saclay, 2022. http://www.theses.fr/2022UPAST075.

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L'utilisation de VLC pour des applications aussi différentes nécessite d'abord une intégration fluide de la technologie dans la pile de protocoles. La première question est de savoir comment un module d'application peut être conscient qu'un lien VLC est disponible, comment il peut découvrir les voisins et comment il peut trouver l'homologue de communication prévu. Dans les WLAN, par exemple, le balisage de couche MAC et le protocole de découverte de voisin IPv6 (NDP) jouent les rôles clés dans la découverte de voisin / route au niveau des couches MAC et réseau, permettant la transmission de données au voisin prévu. Malheureusement, à notre connaissance, aucun travail n'a été effectué sur la découverte de voisins pour les réseaux VLC et les protocoles WLAN / IPv6 ne peuvent pas être simplement connectés à VLC, principalement en raison des caractéristiques uniques du FOV unidirectionnel et étroit. Plus précisément, afin de rendre VLC opérationnel dans des environnements véhiculaires réels, il est nécessaire de concevoir un protocole de contrôle d'accès moyen (MAC) qui assure un échange d'informations V2V continu avec la présence des problèmes difficiles provenant de la dynamique de la mobilité, des interférences multi-utilisateurs. et le bruit ambiant
Using VLC for such different applications requires a smooth integration of the technology into the protocol stack. The first question is how an application module can be aware that a VLC link is available, how it can discover the neighbors, and how it can find the intended communication peer. In WLANs, for instance, the MAC layer beaconing and the IPv6 neighbor discovery protocol (NDP) play critical roles in neighbor/route discovery at both the MAC and network layers, allowing data transmission to the intended neighbor. Unfortunately, to our knowledge, there is no work has been done on neighbor discovery for VLC networks, and the WLAN/IPv6 protocols cannot be plugged into VLC, mainly because of the unique uni-directional and narrow FOV characteristics. More specifically, to make VLC operational in natural vehicular environments, it is necessary to design a Medium Access Control (MAC) protocol that ensures continuous V2V information exchange with the presence of the challenging issues coming from the mobility dynamics, multi-user interference, and environmental noise

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Pazi, Shaban M. "Cost-effective Information and Communication Technology (ICT) infrastructure for Tanziania." Thesis, University of Sussex, 2010. http://sro.sussex.ac.uk/id/eprint/6272/.

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The research conducted an Information and Communication Technology (ICT) field survey, the results revealed that Tanzania is still lagging behind in the ICT sector due to the lack of an internationally connected terrestrial ICT infrastructure; Internet connectivity to the rest of the world is via expensive satellite links, thus leaving the majority of the population unable to access the Internet services due to its high cost. Therefore, an ICT backbone infrastructure is designed that exploits optical DWDM network technology, which un-locks bandwidth bottlenecks and provides higher capacity which will provide ICT services such as Internet, voice, videos and other multimedia interactions at an affordable cost to the majority of the people who live in the urban and rural areas of Tanzania. The research analyses and compares the performance, and system impairments, in a DWDM system at data transmission rates of 2.5 Gb/s and 10 Gb/s per wavelength channel. The simulation results show that a data transmission rate of 2.5 Gb/s can be successfully transmitted over a greater distance than 10 Gb/s with minimum system impairments. Also operating at the lower data rate delivers a good system performance for the required ICT services. A forty-channel DWDM system will provide a bandwidth of 100 Gb/s. A cost analysis demonstrates the economic worth of incorporating existing optical fibre installations into an optical DWDM network for the creation of an affordable ICT backbone infrastructure; this approach is compared with building a completely new optical fibre DWDM network or a SONET/SDH network. The results show that the ICT backbone infrastructure built with existing SSMF DWDM network technology is a good investment, in terms of profitability, even if the Internet charges are reduced to half current rates. The case for building a completely new optical fibre DWDM network or a SONET/SDH network is difficult to justify using current financial data.

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Anne, Matthieu. "Intégration de services perceptuels dans une infrastructure de communication ambiante." Grenoble INPG, 2006. http://www.theses.fr/2006INPG0164.

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L'informatique ubiquiste se matérialise aujourd'hui par une croissance exponentielle du nombre d'objets communicants (OC) dans notre environnement. Dans cette perspective, un système complet de perception de l'environnement peut être constitué dynamiquement par une fédération d'OC répartis. Nous proposons un cadre conceptuel comme support d'un tel système perceptuel dans un environnement distribué. Ce cadre est utilisé pour la modélisation et l'intégration numérique des informations perçues, l'expression de la complémentarité des dispositifs de perception et leurs descriptions en vue d'une intégration dans une infrastructure de services. Nous présentons une méthode permettant au système perceptuel de se composer dynamiquement afin d'exploiter les capacités individuelles des OC et de répondre au mieux aux besoins des applications clientes. Cette approche a été validée par la réalisation d'applications adaptatives au contexte pour la communication ambiante
Entry into the era of Ubiquitous Computing is leading to an exponential growth in the number of communicating device (CD) that can be found in the human environment. A consequence is that it has become possible to dynamically compose systems for perception ofhuman activities from ad hoc assemblies ofavailable CD's. Ln this thesis we present a conceptual framework for dynamic composition of ad hoc perceptual systems. We examine the problem of modelling and integration for fusing perceptual information, the expression of the complementary nature of perceptual devices, and the description of devices required for dynamic composition. We present a method for the dynamic composition of perceptual services designed to exploit the complementary nature of the perceptual devices. This approach has been validated by realization of adaptive user services that are sensitive to the context of human activity

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Rautu, Dorin Marian. "Déploiement temporaire d'une infrastructure de communication à base de drones." Thesis, Toulouse, INPT, 2019. http://www.theses.fr/2019INPT0086.

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Dernièrement, l'utilisation des drones est en pleine expansion dans multiples domaines, par exemple récemment la livraison des colis ou des repas. Parallèlement, les stations de base mobiles sont incapables parfois de satisfaire les exigences des utilisateurs, surtout en cas d'événements imprévus, tels que les catastrophes, les rassemblements ou les rencontres sportives. Une solution prometteuse consiste à profiter de la disponibilité des drones pour pallier les déficiences des réseaux cellulaires en les aidant à satisfaire les demandes par l'extension de la couverture à l'aide des points d'accès installés à bord des drones. Bien que les drones offrent un déploiement rapide, le placement devient l'un des problèmes clés. Dans ce manuscrit nous nous intéressons à ce type de réseaux et au placement des drones en proposant une méthode de déploiement fondée sur une analogie avec la loi de Coulomb, les utilisateurs et les drones agissant comme des charges électriques, les drones étant attirés par les utilisateurs
Recently, the use of drones is booming in many areas, newly in parcel or meal shippement. Analogue to this deployment,the flexibility and resilience requirements of cellular networks are not always met by terrestrial base stations, mainly in the case of unforeseen events, such as natural disasters, gatherings or sports events. One promising solution is to benefit from the availability of drones in order to fulfill the temporary failures of cellular networks by helping them to meet the demands by extending the coverage using the access points installed onboard the UAVs. Although drones offer rapid deployment, the placement becomes one of the key issues. In this thesis we focus on this type of networks and in the drone placement by proposing a deployment method based on an analogy with Coulomb's law, the users and the drones acting like electric charges, the drones being attracted by users

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Rajapakshalage, D. (Dhanushka). "Infrastructure based communication architecture to facilitate autonomous driving and communications." Master's thesis, University of Oulu, 2019. http://jultika.oulu.fi/Record/nbnfioulu-201909242926.

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Abstract. The traditional autonomous vehicle (AV) architecture places a heavy burden on graphics processing units of the vehicle due to heavy signal processing requirements. Ultimately this results in performance degradation in AVs. This is mainly due to advanced sensors, which enable the vision for AVs, like Light Detection and Ranging (LiDAR), radars and cameras. In most of the AV models accepted by many leading automobile companies, LiDAR plays a significant role. It generates a high definition (HD) point cloud of the surroundings to obtain a precise map. AV makes decisions based on that by processing Terabyte (Tb) scale data within the AV. Still, vehicle-mounted LiDARs are not capable of providing information beyond a human driver’s vision. To provide a solution for the above-mentioned drawbacks of the traditional AVs, we propose an infrastructure based communication architecture to facilitate autonomous driving and communications. A set of coordinated LiDAR modules with integrated transceivers, which are mounted at an elevation with a bird’s eye view, can provide a much larger field of vision (FoV). Decisions are taken from a centralized body. We prove the technical feasibility of the system from sensing and communication point of view. The proposed architecture can play a supportive role with traditional AV architectures and it can be applied to many cases such as to automate harbours and factory floors. In the second part of the thesis, we address a resource allocation problem with ultra-reliable and low latency communication (URLLC) for a factory floor. We have analytically proven the capability of the proposed system to establish a reliable (packet error probability less than 10^(-5)) and low latency (less than 1 ms transmission delay) links with sufficient throughput (kilobit scale) using a convex optimization problem. Latency, throughput and reliability variations are studied under the short packet transmission of the proposed system.

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Bertaux, Lionel. "Architecture réseau pour véhicule de transport en commun communiquant." Phd thesis, Université Paul Sabatier - Toulouse III, 2013. http://tel.archives-ouvertes.fr/tel-00910772.

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Avec la démocratisation des appareils mobiles, les transports en commun sont amenés à proposer de nouveaux services à leur usagers et notamment une connexion à Internet. Le véhicule de transport en commun agit alors comme un routeur mobile fournissant une connexion fiable à ses noeuds et doit pour cela être connecté en permanence à un point d'accès. Les zones de couverture étant limitées par les technologies utilisées et par les obstacles, des changements de réseaux sont alors nécessaires et provoquant différents évènements pouvant impacter les performances des protocoles de Transport : introduction de latences dues à la configuration des interfaces, modification des caractéristiques du chemin utilisé par la communication.. Dans cette thèse nous étudions cet impact en déterminant son origine puis nous proposons des solutions visant à le réduire de deux manières : en réduisant les latences introduites par le changement de réseau et en diminuant l'impact de la modification des caractéristiques du réseau.

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Neander, Jonas. "Using Existing Infrastructure as Support for Wireless Sensor Networks." Licentiate thesis, Mälardalen University, Department of Computer Science and Electronics, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-144.

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Denna avhandling handlar om hur befintliga datorinfrastrukturer i t.ex. sjukhus och industrier kan avlasta sensornätverk med energikrävande uppgifter. Vi har forskat på olika aspekter som gör det möjligt att förlänga livslängden på dessa sensornätverk. Avhandlingen presenterar en ny plattform för sensornätverk tillsammans med inledande simuleringar som påvisar att vår plattform ökar livslängden på dessa typer av nätverk.

Generella sensornätverk är uppbyggda av tätt grupperade, trådlösa, batteridrivna datorer som kan vara så små som en kubikmillimeter. Datorerna kallas för sensorer eller sensornoder eftersom de har en eller flera inbyggda sensorer som känner av sin omgivning. En sensor har till uppgift att samla information från sin omgivning, t.ex. temperatur, fuktighet, vibrationer, hjärtslag eller bilder. Sensorerna skickar sedan informationen till en insamlingsstation någonstans i nätverket.

I de typer av tillämpningar vi tittar på är det viktigt att minimera energiförbrukningen, så att man maximerar livslängden på sensornätverket. Avhandlingen presenterar en lösning där befintlig datorinfrastruktur fungerar som hjälpdatorer/avlastare till ett sensornätverk. Hjälpdatorerna, eller basstationerna som vi kallar dem i avhandlingen, hanterar energikrävande uppgifter som t.ex. vilken sensor som ska kommunicera med vem samt vid vilken tidpunkt etc. Då kan sensorerna i nätverket fokusera på att utföra sina egna uppgifter tills dess att basstationen säger att uppgifterna ändrats.

Simuleringar visar att vår plattform kan skicka upp till 97 % mera information till basstationen än en jämförbar plattform med samma energimängd. 88 % av våra sensorer är fortfarande vid liv när den andra plattformens sensorer förbrukat all sin energi.

Ett exempel på hur dessa typer av nätverk kan användas är att övervaka patienters hälsa och kondition i sjukhus eller sjukhem. Patienter behöver inte ha en fast sängplats där en viss typ av medicinskt övervakningsinstrument finns tillgänglig utan kan placeras där det finns en ledig sängplats. Via trådlös kommunikation skickar sensorerna sedan hälsoinformation som t.ex. hjärtfrekvens och blodtryck till en basstation som i sin tur skickar vidare till ett centralt övervakningsinstrument någonstans på sjukhuset. Övervakningsinstrumentet behandlar informationen och larmar personal med rätt kompetens vid behov. Larmet kan skickas till en mobiltelefon eller en liten handdator som personalen alltid bär med sig. Med larmet skickas även information om var patienten befinner sig och all nödvändig data för att personalen snabbt ska kunna ställa en första diagnos. På detta sätt kan man spara in på antalet specialbyggda sängplatser och slippa dyrbara installationer av medicintekniska utrustningar knutna till en sängplats.

Recent advancements in electronic design, such as low-power circuits, energy efficient wireless communication, and improved energy supply, has enabled the vision of wireless sensor networks to become a reality. Wireless sensor networks typically consist of hundreds up to thousands of collaborating low-cost, battery-driven and wireless sensor nodes with scarce resources. The wireless sensor nodes are typical small physical entities, and usually small as a matchbox but can in extreme cases be no larger than a cubic millimeter.

In this thesis we present an architecture called AROS that uses existing infrastructure to aid in the management of wireless sensor networks. As an example, the existing infrastructure could be situated in hospitals or industrial buildings. The existing infrastructure can aid in prolonging the lifetime of the wireless sensor network by having "unlimited'' energy, long range radio capacity, and high-speed computers. We enable prolonged lifetime by centralizing some of the energy consuming administrative functionality of wireless sensor networks.

We show, by simulations, that the AROS architecture is able to prolong the lifetime of the sensor nodes. AROS is compared to a well known cluster based architecture, LEACH. The comparisons show that AROS with static configuration performs at least as well as LEACH in small wireless sensor networks in the size 100x100m, and up to 97 % better in long distance wireless sensor networks in the size of 400x400m. We show that AROS still has got 88 % of its sensor nodes alive when LEACHs' network demises.

In our simulations we have also studied how dynamic network clustering in AROS, using a TDMA scheduler and non-mobile wireless sensor nodes, affects the amount of data received by a base station. We show that AROS is better than LEACH-C in collecting data to the base station with the same total amount of energy for long distance networks and that AROS performs as well or better than LEACH-C in small wireless sensor networks.

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Shang, Lu. "Économie de l’Innovation : le cas du véhicule intelligent." Thesis, Lille 1, 2010. http://www.theses.fr/2010LIL12010.

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Intitulée « Economie de l’innovation – le cas du véhicule intelligent », cette thèse analyse la montée en puissance de l’innovation dans le transport à travers la croissance de l’intelligence artificielle dans les véhicules, les infrastructures et les postes centralisés de régulation et de surveillance. Elle introduit de nouveaux instruments théoriques en économie de l’innovation, définissant le cadre d’une économie comportementale de l’innovation. Ces nouveaux instruments théoriques sont appliqués au cas des concepteurs et des consommateurs-conducteurs du véhicule intelligent. Les apports novateurs portent sur : - l’impact sur la sécurité routière des systèmes intelligents ; - les conditions de l’acceptabilité et de la diffusion des systèmes intelligents ;- l’évolution de l’industrie automobile vers le véhicule intelligent ; - la conception générale du véhicule intelligent : l’intelligence artificielle intégrée dans le véhicule comme un outil ou le véhicule comme accessoire de l’intelligence du mouvement
Titled “Economy of innovation – The case of the intelligent (smart ?) vehicle”, this thesis deals with the growing innovation in the transportation means through the growing importance of artificial intelligence in vehicles, in infrastructures, and in centralized regulation and monitoring centers. It presents new theoretical instruments applicable for the economy of innovation by defining the framework of its behavioral aspects. These new theoretical instruments are applied to the case of designers and to the case of consumers-drivers of the intelligent vehicle. Innovative topics are the following: - the impact of intelligent systems on road safety, - the conditions for accepting and spreading intelligent systems, - the evolution of the car industry towards the intelligent vehicle, - the global design of the intelligent vehicle: the artificial intelligence embedded in the vehicle as an assistant tool or the vehicle as secondary to the intelligence of the movement

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Deaton, Brady James. "The influence of communications infrastructure on agricultural growth /." This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-12052009-020226/.

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Gessler, Fredrik. "The development of wireless infrastructure standards." Doctoral thesis, KTH, Industrial Economics and Management, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3338.

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This thesis treats the development of wirelessinfrastructure standards resulting from co-operative research,development and standardisation efforts. It strives to identifykey influences on this development process, and toconceptualise the process itself. With this as a basis, it goeson to analyse potential implications for companies in thewireless industry, and for the role of co-operatively developedstandards in this field. The focus of the thesis is on thecreation of standards through development efforts, rather thanthe selection of standards in official forums, or by themarket.

Two deep empirical studies provide the foundation of thethesis. The first one deals with the development of the DigitalEnhanced Cordless Telecommunications (DECT) standard. DECT isan open, de jure standard that was designed by a number oftelecommunications manufacturers. The standard was formallyapproved by the European Telecommunications Standards Institute(ETSI) in 1992. The second study treats the development ofThird Generation (3G) mobile infrastructure standards, withspecial focus on the radio interface standards such as WidebandCode Division Multiple Access (WCDMA). The development of thefamily of 3G standards today known as International MobileTelecommunications 2000 (IMT-2000) began more than 15 yearsago, and the first version of formally adopted air interfacestandards was released in 2000 by the Third GenerationPartnership Project (3GPP). The research and development goinginto the specification of the standards has involved all majorplayers in the wireless industry.

The two studies have involved numerous interviews withindustry professionals, academics, regulators, and others. Inaddition, a multitude of technical reports and articles,meeting documents, press releases, etc., have been analysed toprovide good documentation of the development processes. Theempirical studies have also been complemented with extensiveliterature studies into the areas of technical development andstandardisation.

Apart from two "thick descriptions" of importantdevelopments in the wireless industry, the main result of thethesis is a conceptual framework for how wirelessinfrastructure standards are developed. The frameworkdemonstrates that the development is influenced by thepre-history of the standard in terms of existing systems, aswell as research and development that had been pursued inrelevant fields. Furthermore it shows that preconceptions ofmarket needs and user behaviour are key aspects of the designof the standard. During the development process technologicalcontroversies tend to appear as a manifestation of differentcompetitive intentions among the involved players. In theresolution of these controversies, the stage is set for futurecompetition between suppliers of products adhering to thestandard.

The pre-history of a standard, as well as the marketpreconceptions, originate in the semi-independent processes oftechnological development, and market diffusion, respectively.When the time frame of the conceptual framework is expanded,generations of standards following upon each other can beidentified. Each new generation incorporates new developments,and improved functionality and performance, but also builds onexisting solutions. The technical standards, such as DECT orWCDMA, act as wasp-like waists between the technologicaldevelopment and the market diffusion processes.

The thesis shows that wireless infrastructure standards to agreat extent are created through technical development efforts.The processes also involve political, competitive, andregulatory deliberations, but technical content often definesthe form even for these debates. This points to the importanceof considering standards-setting in terms of a developmentprocess rather than as a set of formal decisions made by astandards body. A consequence of this is that companiesdesiring to influence the design of a particular standardshould strive to be in the forefront of research anddevelopment related to that standardisation effort. This is thekey to leading the development of new wireless infrastructurestandards.

Key words:standards, de jure standards,standardisation, standards-development, competition,technological development, wireless communications, wirelessinfrastructures, telecommunications, WCDMA, DECT, IMT-2000,FPLMTS, 3G

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Corp, Lovisa, and Mikael Mattsson. "Security and Infrastructure for Mobile Phone Payments using Near Field Communication." Thesis, KTH, Maskinkonstruktion (Inst.), 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-99335.

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Near Field Communication (NFC) is a short distance radio frequency communication technology that is suitable for use in a mobile handset. The technology enables payment cards, transport tickets and access cards to be replaced by software in the handset, thereby creating a mobile wallet with virtual cards. This thesis is focused on the mobile phone payment environment including NFC technology, industry collaboration and security. The research is based on literature studies, interviews and the development of a prototype system. The prototype was developed to demonstrate payments and loyalty membership transactions using an NFC-equipped mobile phone. The technology of NFC is ready for commercial use since the most critical standards have been published. What remains to be done before widespread technology implementation is to establish the payment infrastructure. This consists of compatible systems and a solid business model supported by industry collaboration agreements. When wireless communication and embedded systems including software applications are introduced to the payment environment, new threats to payment security arise. Due to this, there is a need for continuous research to maintain the security and suppress new attack methods but the current protection against attacks in these areas is strong. A suggestion for future work is to further study the threats from software attacks as well as usability aspects regarding mobile phone payment systems. Another suggestion is to further develop the prototype for integration into an existing payment system.
Near Field Communication är en radiokommunikationsteknologi för korta avstånd som lämpar sig väl för användning i mobiltelefoner. Teknologin möjliggör att betalkort, transportbiljetter och accesskort kan ersättas med mjukvara i telefonen, vilket innebär att mobiltelefonen kan användas som en virtuell plånbok. Det här examensarbetet fokuserar på området kring mobila betalningar. Rapporten är uppdelad i tre huvudteman: NFC-teknologi, affärsmodell och säkerhet. Efterforskningen inom området är baserad på litteraturstudier, intervjuer och utvecklingen av en prototyp. Prototypen har utvecklats för demonstration av hur betalning och bonuskortstransaktioner via mobiltelefon kan utföras. NFC-teknologin är redo för kommersiellt bruk tack vare att de mest kritiska standarderna är publicerade. Det som kvarstår innan teknologin kan implementeras på bred front är infrastrukturen kring betalningar med mobiltelefon. Denna består av kompatibla system och en solid affärsmodell understödd av överenskommelser inom industrin. När trådlös kommunikation och inbyggda system inklusive mjukvaruapplikationer introduceras i betalningsmiljön, uppkommer nya hot mot betalningssäkerheten. På grund av detta behövs det kontinuerlig forskning för att upprätthålla säkerheten och stävja nya attackmetoder men det nuvarande skyddet mot attacker inom dessa områden är starkt. Ett förslag för vidare arbete är att utföra ytterligare studier om mjukvaru-attacker och om användbarhet beträffande betalsystem för mobiltelefoner. Ett annat förslag är att vidareutveckla prototypen för integrering i ett existerande betalsystem.

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Böhm, Annette, and Magnus Jonsson. "Real-time communication support for cooperative, infrastructure-based traffic safety applications." Högskolan i Halmstad, Centrum för forskning om inbyggda system (CERES), 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-16211.

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The implementation of ITS (Intelligent Transport Systems) services offers great potential to improve the level of safety, efficiency and comfort on our roads. Although cooperative traffic safety applications rely heavily on the support for real-time communication, the Medium Access Control (MAC) mechanism proposed for the upcoming IEEE 802.11p standard, intended for ITS applications, does not offer deterministic real-time support, that is, the access delay to the common radio channel is not upper bounded. To address this problem, we present a framework for a vehicle-to-infrastructure-based (V2I) communication solution extending IEEE 802.11p by introducing a collision-free MAC phase assigning each vehicle an individual priority based on its geographical position, its proximity to potential hazards and the overall road traffic density. Our solution is able to guarantee the timely treatment of safety-critical data, while minimizing the required length of this real-time MAC phase and freeing bandwidth for best-effort services (targeting improved driving comfort and traffic efficiency). Furthermore, we target fast connection setup, associating a passing vehicle to an RSU (Road Side Unit), and proactive handover between widely spaced RSUs. Our real-time MAC concept is evaluated analytically and by simulation based on a realistic task set from a V2I highway merge assistance scenario.

Copyright © 2011 Annette Böhm and Magnus Jonsson. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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Unyapoth, Asis. "Nomadic π-calculi : expressing and verifying communication infrastructure for mobile computation." Thesis, University of Cambridge, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.621172.

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Guidi, Davide <1977&gt. "A communication infrastructure to support knowledge level agents on the web." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2007. http://amsdottorato.unibo.it/374/1/TesiDottorato_Davide_Guidi.pdf.

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Agent Communication Languages (ACLs) have been developed to provide a way for agents to communicate with each other supporting cooperation in Multi-Agent Systems. In the past few years many ACLs have been proposed for Multi-Agent Systems, such as KQML and FIPA-ACL. The goal of these languages is to support high-level, human like communication among agents, exploiting Knowledge Level features rather than symbol level ones. Adopting these ACLs, and mainly the FIPA-ACL specifications, many agent platforms and prototypes have been developed. Despite these efforts, an important issue in the research on ACLs is still open and concerns how these languages should deal (at the Knowledge Level) with possible failures of agents. Indeed, the notion of Knowledge Level cannot be straightforwardly extended to a distributed framework such as MASs, because problems concerning communication and concurrency may arise when several Knowledge Level agents interact (for example deadlock or starvation). The main contribution of this Thesis is the design and the implementation of NOWHERE, a platform to support Knowledge Level Agents on the Web. NOWHERE exploits an advanced Agent Communication Language, FT-ACL, which provides high-level fault-tolerant communication primitives and satisfies a set of well defined Knowledge Level programming requirements. NOWHERE is well integrated with current technologies, for example providing full integration for Web services. Supporting different middleware used to send messages, it can be adapted to various scenarios. In this Thesis we present the design and the implementation of the architecture, together with a discussion of the most interesting details and a comparison with other emerging agent platforms. We also present several case studies where we discuss the benefits of programming agents using the NOWHERE architecture, comparing the results with other solutions. Finally, the complete source code of the basic examples can be found in appendix.

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Guidi, Davide <1977&gt. "A communication infrastructure to support knowledge level agents on the web." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2007. http://amsdottorato.unibo.it/374/.

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Agent Communication Languages (ACLs) have been developed to provide a way for agents to communicate with each other supporting cooperation in Multi-Agent Systems. In the past few years many ACLs have been proposed for Multi-Agent Systems, such as KQML and FIPA-ACL. The goal of these languages is to support high-level, human like communication among agents, exploiting Knowledge Level features rather than symbol level ones. Adopting these ACLs, and mainly the FIPA-ACL specifications, many agent platforms and prototypes have been developed. Despite these efforts, an important issue in the research on ACLs is still open and concerns how these languages should deal (at the Knowledge Level) with possible failures of agents. Indeed, the notion of Knowledge Level cannot be straightforwardly extended to a distributed framework such as MASs, because problems concerning communication and concurrency may arise when several Knowledge Level agents interact (for example deadlock or starvation). The main contribution of this Thesis is the design and the implementation of NOWHERE, a platform to support Knowledge Level Agents on the Web. NOWHERE exploits an advanced Agent Communication Language, FT-ACL, which provides high-level fault-tolerant communication primitives and satisfies a set of well defined Knowledge Level programming requirements. NOWHERE is well integrated with current technologies, for example providing full integration for Web services. Supporting different middleware used to send messages, it can be adapted to various scenarios. In this Thesis we present the design and the implementation of the architecture, together with a discussion of the most interesting details and a comparison with other emerging agent platforms. We also present several case studies where we discuss the benefits of programming agents using the NOWHERE architecture, comparing the results with other solutions. Finally, the complete source code of the basic examples can be found in appendix.

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Munasinghe, Kumudu S., University of Western Sydney, of Science Technology and Environment College, and School of Computing and Information Technology. "VPN over a wireless infrastructure : evaluation and performance analysis." THESIS_CSTE_CIT_Munasinghe_K.xml, 2005. http://handle.uws.edu.au:8081/1959.7/662.

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This thesis presents the analysis and experimental results for an evaluation of the performance and Quality of Service (QoL) levels of a virtual private network( QoL) levels of a Virtual Private Network (VPN) implementation of an IEEE 802.11b wireless infrastructure. The VPN tunnelling protocol considered for the above study is IP security (IPSec). The main focus of the research is to identify the major performance limitations and their underlying causes for such VPN implementations under study. The experimentation and data collection involved in the study spans over a number of platforms to suit a range of practical VPN implementations over a wireless medium. The collected data includes vital QoS and performance measures such as the application throughput, packet loss, jitter, and round-trip delay. Once the baseline measure is established, a series of experiments are conducted to analyse the behaviour of a single IPSec VPN operating over an IEEE 802.11b infrastructure, after which the experimentation is extended by investigating the trends of the performance metrics of a simultaneously multiple VPN setup. The overall results and analysis of the investigation concludes that the CPU processing power, payload data size, packet generation rate and the geographical distance are critical factors affecting the performance of such VPN tunnel implementations. Furthermore, it is believed that these results may give vital clues for enhancing and achieving optimal performance and QoS levels for VPN applications over WLANs
Master of Science (Hons.)

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Divekar, Tapan. "PEMOCO an infrastructure for personal mobile e-commerce for Java-enabled smart phones /." [Gainesville, Fla.] : University of Florida, 2001. http://purl.fcla.edu/fcla/etd/UFE0000314.

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Thesis (M.S.)--University of Florida, 2001.
Title from title page of source document. Document formatted into pages; contains ix, 73 p.; also contains graphics. Includes vita. Includes bibliographical references.

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Deaton, Brady J. "The influence of communications infrastructure on agricultural growth." Thesis, Virginia Tech, 1993. http://hdl.handle.net/10919/46149.

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Gukhool, Balkrishna Sharma. "Communication continue en mode infrastructure dans les réseaux véhiculaires utilisant IEEE 802.11P." Mémoire, Université de Sherbrooke, 2009. http://savoirs.usherbrooke.ca/handle/11143/1543.

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Les handovers sont des phénomènes inévitables dans les réseaux sans-fil mobiles. Lors du passage d'une station mobile d'un point d'accès à un autre, le handover affecte la qualité des transmissions, et ainsi, il est néfaste à la performance des réseaux sans-fil. De nombreuses techniques de réduction du délai lié au handover ont été proposées, mais la plupart ne sont pas adaptées aux attentes du nouveau type de réseau sans-fil mobile qu'est le réseau véhiculaire. Ce travail propose donc l'implémentation d'une méthode de réduction du délai encouru lors d'un handover dans les réseaux véhiculaires qui opèrent sous une technologie d'accès sans-fil adaptée pour les besoins des réseaux véhiculaires. Le travail est composé de deux blocs : le premier est l'implémentation d'IEEE 802.11p, qui est une variante de la norme générique d'IEEE 802.11 et qui est développée spécialement pour l'accès dans les réseaux véhiculaires, dans un simulateur de réseaux. L'autre partie concerne le choix d'une méthode de réduction du délai lié à l'étape de la recherche du handover. En tenant compte des réalités technologiques, le choix s'est porté sur une technique préconisant l'utilisation des cache pour contenir et diffuser de l'information sur les points d'accès avoisinants. La méthode proposée a été testée et a donné de très bons résultats réalistes. L'intégration des modules complémentaires pour refléter l'ensemble de la technique proposée au niveau du simulateur s'est aussi faite sans problèmes majeurs.

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Khodaei, Mohammad. "Secure and Privacy Preserving Vehicular Communication Systems: Identity and Credential Management Infrastructure." Licentiate thesis, KTH, Kommunikationsnät, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-193030.

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Vehicular Communication (VC) systems can greatly enhance road safety and transportation efficiency. Vehicles are equipped with sensors to sense their surroundings and the internal Controller Area Network (CAN) bus. Hence, vehicles are becoming part of a large-scale network, the so-called Internet of Vehicles (IoV). Deploying such a large-scale VC system cannot materialize unless the VC systems are secure and do not expose their users’ privacy. Vehicles could be compromised or their sensors become faulty, thus disseminating erroneous information across the network. Therefore, participating vehicles should be accountable for their actions. Moreover, user privacy is at stake: vehicles should disseminate spatio-temporal information frequently. Due to openness of the wireless communication, an observer can eavesdrop the communication to infer users’ sensitive information, thus profiling users. The objective is to secure the communication, i.e., prevent malicious or compromised entities from affecting the system operation, and ensure user privacy, i.e., keep users anonymous to any external observer but also for security infrastructure entities and service providers.In this thesis, we focus on the identity and credential management infrastructure for VC systems, taking security, privacy, and efficiency into account. We begin with a detailed investigation and critical survey of the standardization and harmonization efforts. We point out the remaining challenges to be addressed in order to build a Vehicular Public-Key Infrastructure (VPKI). We provide a VPKI design that improves upon existing proposals in terms of security and privacy protection and efficiency. More precisely, our scheme facilitates multi-domain operations in VC systems and enhances user privacy, notably preventing linking of pseudonyms based on timing information and offering increased protection in the presence of honest-but-curious VPKI entities. We further extensively evaluate the performance of the full-blown implementation of our VPKI for a large-scale VC deployment. Our results confirm the efficiency, scalability and robustness of our VPKI.

QC 20160927

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Qiu, Bin. "Next Generation Information Communication Infrastructure and Case Studies for Future Power Systems." Diss., Virginia Tech, 2002. http://hdl.handle.net/10919/27308.

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As the power industry enters the new century, powerful driving forces, uncertainties and new services and functions are compelling electric utilities to make dramatic changes in the way they communicate. Expanding network services such as real time monitoring are also driving the need for more increasing bandwidth in the communication network backbone. These needs will grow further as new remote real-time protection and control applications become more feasible and pervasive. This dissertation addresses two main issues for the future power system information infrastructure: communication network infrastructure and associated power system applications. Optical network no doubt will become the predominate network for the next generation power system communication. The rapid development of fiber optic network technology poses new challenges in the areas of topology design, network management and real time applications. Based on advanced fiber optic technologies, an all-fiber network was investigated and proposed. The study will cover the system architecture and data exchange protocol aspects. High bandwidth, robust optical network could provide great opportunities to the power system for better service and efficient operation. In the dissertation, different applications were investigated. One of the typical applications is the SCADA information accessing system. An Internet-based application for the substation automation system will be presented. VLSI (Very Large Scale Integration) technology is also used for one-line diagrams auto-generation. High transition rate and low latency optical network is especially suitable for power system real time control. In the dissertation, a new local area network based Load Shedding Controller (LSC) for isolated power system will be presented. By using PMU and fiber optic network, an AGE (Area Generation Error) based accurate wide area load shedding scheme will also be proposed. The objective is to shed the load in the limited area with minimum disturbance.
Ph. D.

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Plainchault, Patrick Bosch Thierry. "Sécurisation de la conduite par communication véhicule infrastructure à base de transpondeurs." Toulouse : INP Toulouse, 2005. http://ethesis.inp-toulouse.fr/archive/00000137.

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Davies, Jessica. "Expanding the spatial data infrastructure model to support spatial wireless applications /." Connect to thesis, 2003. http://eprints.unimelb.edu.au/archive/00001044.

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Munasinghe, Kumudu S. "VPN over a wireless infrastructure : evaluation and performance analysis." Thesis, View thesis, 2005. http://handle.uws.edu.au:8081/1959.7/662.

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This thesis presents the analysis and experimental results for an evaluation of the performance and Quality of Service (QoL) levels of a virtual private network( QoL) levels of a Virtual Private Network (VPN) implementation of an IEEE 802.11b wireless infrastructure. The VPN tunnelling protocol considered for the above study is IP security (IPSec). The main focus of the research is to identify the major performance limitations and their underlying causes for such VPN implementations under study. The experimentation and data collection involved in the study spans over a number of platforms to suit a range of practical VPN implementations over a wireless medium. The collected data includes vital QoS and performance measures such as the application throughput, packet loss, jitter, and round-trip delay. Once the baseline measure is established, a series of experiments are conducted to analyse the behaviour of a single IPSec VPN operating over an IEEE 802.11b infrastructure, after which the experimentation is extended by investigating the trends of the performance metrics of a simultaneously multiple VPN setup. The overall results and analysis of the investigation concludes that the CPU processing power, payload data size, packet generation rate and the geographical distance are critical factors affecting the performance of such VPN tunnel implementations. Furthermore, it is believed that these results may give vital clues for enhancing and achieving optimal performance and QoS levels for VPN applications over WLANs

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Ward, Ben. "Integrated asset management systems for water infrastructure." Thesis, University of Exeter, 2015. http://hdl.handle.net/10871/18819.

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Owners of infrastructure assets have responsibility for the management of a diverse portfolio of civil engineering assets. These assets make up the foundations of modern society and are arguably pivotal in the economic growth and wellbeing of a nation. It is of no surprise therefore, that asset management business practises have risen in popularity as the UK’s infrastructure asset base continues to grow and inevitably ages with time. In the context of water and waste water infrastructure assets, which communities rely upon for health, economy and environmental sustainability, it is widely acknowledged that these assets have historically suffered from underinvestment. Whilst funding shortfalls have been evidenced historically, through the inadequacy of infrastructure to meet the needs and challenges of the past, it is of great concern that infrastructure expenditure is reducing in real terms as a result of the global financial crisis. This is leading to a widening funding gap between the available and the required finances for infrastructure investment which is further compounded by natural phenomena and human behaviours, i.e., climate change, population growth and urbanisation. To further intensify the problem, asset planning and management in the water industry is considered a complex and challenging discipline because of high interdependencies and the vast quantity of assets themselves. In acknowledgement of this global position, this thesis seeks to address some of the key challenges faced by utility companies in the adoption of asset management best practice across water and waste water assets, namely: • Operational decision making - the efficient and effective specification of least-cost rehabilitation programmes from condition information that ensure behavioural alignment with an organisations strategic objectives. • Tactical decision making - achieving risk based asset level inspection prioritisation that considers serviceability performance, for two particularly challenging asset groups: i.) High value - low volume assets and ii). Low value - high volume buried infrastructure. • Strategic decision making - identifying optimal long-term investment plans and asset management policies for assets that have previously not benefited from such technological advancements. To improve upon operational decision making, the author capitalises on the availability of condition inspection information for buried sewerage infrastructure by applying advanced optimisation techniques to help form an environment where the decision makers is presented with an array of optimal rehabilitation solutions. The trade-off curve that is presented uniquely evaluates solutions for the benefits they offer in-terms of: condition improvement, cost and operational performance. A financially favourable comparison (up to 45% saving) is drawn between the optimisation results which are automatically generated by the model and those that have been developed manually by experienced engineers in a ‘real world’ case study. However, it could be argued that the greatest benefit arises from the trade curve of feasible solutions which are presented to the decision maker across a range of investment levels. In recognition that tactical and strategic decision making have been the focus of a substantial amount of research for commonly found infrastructure assets, i.e., public sewers and water mains, a focus has been placed on improving upon and adopting best practise across infrastructure assets which have not previously benefited from the technological developments across these decision making levels. Firstly, a methodology for translating standardised condition inspection information into more meaningful reliability scores, to support risk based planning and decision making, is presented for service reservoirs. A service reservoir can be regarded as high value- low volume infrastructure asset and would typically have its condition evaluated between 1 (poor) to 5 (good). A case study demonstrates how this new reliability scoring mechanism has been successfully applied during a typical structural condition survey. The output from this process is a fully document reliability assessment for each component of the service reservoir. The output can be aggregated to provide an overall reliability assessment for the structure and/or used to target specific remedial works to troublesome components. Secondly, two methodologies are presented which address the fact that high volume – low value infrastructure assets across both the water distribution and wastewater collection networks, are typically less well understood and often sub-optimally managed in comparison to more critical or higher value assets. 1. A methodology has been developed to help UK water companies overcome the recent legislative changes associated with Section105A of the Water Act; which has transferred ownership of the private sewer network to UK water companies. The new methodology which has been developed, has allowed one of the UK’s water and sewerage companies to initiate a proactive asset management programme with the aim of addressing the deteriorating condition of these assets whilst also tackling their associated serviceability performance. Initially, a number of GIS tools are used to provide an estimate of the likely extent of the transferred network before a well-established public sewer deterioration model is used to predict the condition and operational performance of these S105A assets over time. 2. A novel deterioration modelling framework is developed by coupling the latest geospatial technologies with statistical deterioration modelling techniques. The modelling framework is specifically applied to small diameter water distribution assets (25-50mm diameter), known as communication pipes, which connect individual properties to the water distribution mains. Reliability curves are developed from failure data provided by two UK based Water Companies that have captured specific communication pipe failure records since 2001. The deterioration modelling curves and supporting data are compared and contrasted to demonstrate the robustness of this modelling approach, which is shown to be capable of modelling failure rates to a high degree of accuracy. This was validated by comparing the predicted number of failures against three years of failure data not used during the model building process. The yearly failure counts were predicted to within +/-5% accuracy and the overall cumulative modelled failure count at the end of 2014 was predicted within 1%. To conclude, the successful deterioration modelling tools for communication pipes are explored further, via the development of a strategic whole life cost optimisation framework for these assets. The outputs from the previous geospatial mapping tool are used alongside the calibrated Weibull deterioration curves to drive a whole life cost and performance analysis. Against this improved understanding of whole life costs, an optimisation algorithm is used to evaluate the trade-off between whole life costs (totex) and the prevention of future asset failures (serviceability). The model successfully identifies optimised investment policies according to the decision maker’s priorities which is evidenced in a case study that shows outperformance against existing maintenance policies for these assets. Financial savings in the region of £8.5M, or the prevention of 1,320 asset failures, were shown to be possible over a 25 years planning horizon in the case study. For the avoidance of confusion, the term ‘integrated’ is considered from the perspective of the three decision making levels associated with the management of an asset, namely: strategic, tactical and operational decision making. Therefore, data quality improvements and the management of information transactions between decisional levels are inherently considered within all of the methodologies developed in this thesis.

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Cai, Shichao. "Système d'information et d'assistance à la conduite pour la mise en oeuvre de la sécurité à bord d'un véhicule." Phd thesis, Université de Technologie de Belfort-Montbeliard, 2011. http://tel.archives-ouvertes.fr/tel-00673897.

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Dans un souci d'amélioration des conditions de sécurité routière, l'union Européenne s'est fixée comme objectif de réduire le nombre de décès sur les routes. Le projet Européen ASSET aspire à l'amélioration de la sécurité et de la protection des conducteurs, des engins roulants ainsi que des infrastructures routières. Notre travail de thèse s'inscrit pleinement dans le cadre du projet ASSET et a pour application le développement d'outils théoriques et pratiques intégrant un véhicule lambda pour l'amélioration de la sécurité routière. L'objectif de la thèse est de réaliser ou d'utiliser les bus de communication de terrain au sein du véhicule, permettant à ce dernier de communiquer avec tous ses organes et de récolter des informations importantes qui seront dans un deuxième temps communiquées en liaison sans fil aux autres véhicules (ou à une centrale) afin de renseigner sur l'état du véhicule ou de la route. Nous proposons un système ubiquitaire intelligent nommé PCAN (Pervasif Controller Area Network), qui aspire à être un système embarqué automatique et intelligent dans un véhicule pour améliorer la sécurité routière et le confort de conduite. Concrètement, ce système PCAN permet de recueillir des informations contextuelles sur l'environnement extérieur et intérieur du véhicule et aussi de communiquer en liaison sans fil avec d'autres systèmes externes. Lesystème est composé d'un bus CAN ouvert, d'un système de communication sans fil et d'un ordinateur embarqué. Le bus CAN ouvert est composé de nœuds permettant l'ajout direct de différents capteurs ou actionneurs. Deux différents ordinateurs embarqués ont été utilisés : Le CompactRio et un ordinateur portable. Grâce à ces derniers, des modules de communication sans fil ont été utilisés permettant l'échange des données par Wi-Fi, ZigBee et GPRS. Toutes les informations collectées peuvent être affichées au conducteur grâce à un écran tactile.Le système PCAN est implémenté dans un véhicule Citroën C4. Sur la base de ce véhicule intelligent, nous avons développé des scénarios et applications afin d'améliorer la sécurité routière et le confort de conduite. Une application de l'avertissement de l'ABS est développée et testée expérimentalement pour deux scénarios : un avertissement par V2V direct et un avertissement par V2I ou V2V indirect. Concernant l'avertissement V2V en communication ZigBee, une application de la localisation de véhicule en détresse est proposée grâce à une modélisation mathématique de la distance en fonction de la qualité du signal. Par ailleurs, un algorithme d'optimisation est réalisé pour rechercher la station de service (ou le point de recharge dans le cas d'un véhicule électrique) optimale en fonction de différents critères.Le système PCAN peut recueillir des informations contextuelles sur le véhicule et son environnement, il peut également établir des communications sans fil. Ces fonctionnalités sont enrichies par la possibilité d'effectuer le contrôle/commande de certains composants du véhicule raccordés au PCAN. Nous utilisons le système PCAN afin de contrôler et de commander à distance un actionneur mécatronique du véhicule. La méthode de commande est basée sur une association originale d'un PID avec un régulateur à base de Logique Floue (LF).

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Gordon, George S. D. "Design of indoor communication infrastructure for ultra-high capacity next generation wireless services." Thesis, University of Cambridge, 2013. https://www.repository.cam.ac.uk/handle/1810/245080.

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The proliferation of data hungry wireless devices, such as smart phones and intelligent sensing networks, is pushing modern wireless networks to their limits. A significant shortfall in the ability of networks to meet demand for data is imminent. This thesis addresses this problem through examining the design of distributed antenna systems (DAS) to support next generation high speed wireless services that require high densities of access points and must support multiple-input multiple-output (MIMO) protocols. First, it is shown that fibre links in DAS can be replaced with low-cost, broadband free-space optical links, termed radio over free-space optics (RoFSO) links. RoFSO links enable the implementation of very high density DAS without the need for prohibitively expensive cabling infrastructure. A 16m RoFSO link requiring only manual alignment is experimentally demonstrated to provide a spurious-free dynamic range (SFDR) of > 100dB/Hz^2/3 over a frequency range from 300MHz- 3.1GHz. The link is measured to have an 802.11g EVM dynamic range of 36dB. This is the first such demonstration of a low-cost broadband RoFSO system. Following this, the linearity performance of RoFSO links is examined. Because of the high loss nature of RoFSO links, the directly-modulated semiconductor lasers they use are susceptible to high-order nonlinear behaviour, which abruptly limits performance at high powers. Existing measures of dynamic range, such as SFDR, assume only third-order nonlinearity and so become inaccurate in the presence of dominant high-order effects. An alternative measure of dynamic range called dynamic-distortion-free dynamic range (DDFDR) is then proposed. For two different wireless services it is observed experimentally that on average the DDFDR upper limit predicts the EVM knee point to within 1dB, while the third-order SFDR predicts it to within 6dB. This is the first detailed analysis of high-order distortion effects in lossy analogue optical links and DDFDR is the first metric able to usefully quantify such behaviour. Next, the combination of emerging MIMO wireless protocols with existing DAS is examined. It is demonstrated for the first time that for small numbers of MIMO streams (up to ~4), the capacity benefits of MIMO can be attained in existing DAS installations simply by sending the different MIMO spatial streams to spatially separated remote antenna units (RAU). This is in contrast to the prevailing paradigm of replicating each MIMO spatial stream at each RAU. Experimental results for two representative DAS layouts show that replicating spatial streams provides an increase of only ~1% in the median channel capacity over merely distributing them. This compares to a 3-4% increase of both strategies over traditional non-DAS MIMO. This result is shown to hold in the multiple user case with 20 users accessing 3 base stations. It is concluded that existing DAS installations offer negligible capacity penalty for MIMO services for small numbers of spatial streams, including in multi-user MIMO scenarios. Finally, the design of DAS to support emerging wireless protocols, such as 802.11ac, that have large numbers of MIMO streams (4-8) is considered. In such cases, capacity is best enhanced by sending multiple MIMO streams to single remote locations. This is achieved using a novel holographic mode division multiplexing (MDM) system, which sends each separate MIMO stream via a different propagation mode in a multimode fibre. Combined channel measurements over 2km of mode-multiplexed MMF and a typical indoor radio environment show in principle a 2x2 MIMO link providing capacities of 10bit/s/Hz over a bandwidth of 6GHz. Using a second experimental set-up it is shown that the system could feasibly support at least up to a 4x4 MIMO system over 2km of MMF with a condition number >15dB over a bandwidth of 3GHz, indicating a high degree of separability of the channels. Finally, it is shown experimentally that when a fibre contains sharp bends (radius between 20mm and 7.2mm) the first 6 mode-groups used for multiplexing exhibit no additional power loss or cross-coupling compared with unbent fibre, although mode-groups 7, 8 and 9 are more severely affected. This indicates that at least 6x6 multiplexing is possible in standard installations with tight fibre bends.

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Munasinghe, Kumudu S. "VPN over a wireless infrastructure evaluation and performance analysis /." View thesis, 2005. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20050920.141716/index.html.

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Thesis (M.Sc. (Hons.)) -- University of Western Sydney, 2005.
A thesis submitted in fulfillment of the requirements for the award of the degree Master of Science (Honours) to the University of Western Sydney on March 2005. Includes bibliography.

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Chu, Carlson, and 朱嘉遜. "Development of broadband information infrastructure in Hong Kong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31268742.

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