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Ad hoc networking research has received considerable attention in recent years as it represents the next phase of networking evolution. Efficient and reliable routing of data from the source to destination with minimal power consumption remains the crux of the research problem. Fading mechanisms inherent in wireless communications can impact the packet routing mechanisms in these types of networks. In this thesis, we develop a mathematical framework for evaluating several network diversity schemes that take advantage of the random nature of fading to provide/ enhance the network performance. The efficacy of these different network diversity mechanisms are examined in slow-fading, frequency non-selective Rice and Nakagami-m multipath fading channels. Performance metrics such as the end-to-end outage probability and the end-to-end average symbol error rate are studied in the analysis of these types of networks with the proposed network diversity schemes. Numerical results reveal that the proposed schemes can offer significant power efficiency improvement in a variety of operating scenarios of practical interest. / Master of Science

International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Ad hoc networking protocols enable the formation of self-organizing networks with automatic selfhealing operation in dynamic environments. There are a number of existing or planned ad hoc implementations and a body of research on protocols and performance. Ad Hoc technologies promise significant impact in future communications architectures. This paper presents a general overview of ad hoc networking and presents specific examples, including a recent implementation of a prototype ad hoc networked sensor system. The protocols used have unique characteristics derived by tailoring particular protocols to the specific application requirements. The potential relevance of ad hoc networking to possible telemetry applications is discussed.

<p>Under min sista termin på lärarprogrammet har fokus bland annat legat på betyg. Vanligtvis är det politikers syn på betyg som framkommer i betygsdebatten. Syftet med min undersökning är att lyfta fram elevperspektivet i betygsdebatten. Detta ledde fram till min huvudfråga om vilken syn gymnasieelever har på betyg. För att få reda på detta ställde jag delfrågor om betygens rättvisa, betygens existens och upplevelsen av betyg. Metoden jag använde för att besvara frågorna var intervjuer med gymnasieelever på Karlbergsgymnasiet i Åmål. Resultatet av intervjuerna sammanställdes genom ad hoc-metoden, vilket innebar att jag försökte finna mönster i elevernas svar.</p><p>Det jag kom fram till i min undersökning är att majoriteten av gymnasieeleverna tycker att betygen inte är rättvisa. Men de anser att betyg behövs eftersom de fungerar som urvalsinstrument till högre studier och jobb och ger information om hur eleven ligger till. Flera elever vill ha fler betygssteg, för att betygen ska bli mer rättvisa. Vissa elever tycker betyg är dåligt för att de jämför sig med andra och får dåligt självförtroende av det. De negativa känslorna som ett dåligt betyg kan frambringa gör att vissa elever ger upp skolarbetet. Men andra elever motiveras av betyg och studerar mer på grund av dem. Detta visar på komplexiteten i fenomenet betyg. Gymnasieeleverna har både en positiv och negativ syn på betyg.</p> / <p>During my last term of teacher training the syllaby content, among other subjects, have been focused on school grades. Commonly the debate concerning school grades reflect the opinions of party politicians. The purpose of my research is to enhance the perspective of pupils´ opinions in this same debate. This very purpose brought on my main issue concerning the idea about grades among upper secondary school pupils. In order to investigate this issue I have formulated questions, put to upper secondary pupils, about the apprehension of fairness or justice in school grades, their opinion about the presence of school grades and their personal experience of them. The research method choosen to answer my questions was interview. Upper secondary pupils in a community of southern Sweden were interviewed.</p><p>The answers were analysed and structured according to the ad-hoc method, indicating that I tried to reveal patterns among the expressions given by the pupils.</p><p>The findings from my study imply that a majority of the students interviewed do consider grades to be unfair. They do think though that grades are needed as a means of selection for higher education as well as employment and that grades do inform about the level of achievement of the pupils. Several pupils in my study advocate an increased number of grade levels to promote more justice in the use of school grades. Some pupils think that grades are bad because they use to compare themselves to other schoolmates, a behaviour that tends to lower their ego. The negative feelings that may be accomplished by low grades tend to make some pupils give up school. Other students find grades motivating and grades make them study more earnestly. These answers do reveal the complexity in the issue of school grades. Upper secondary pupils do hold positive as well as negative attitudes towards school grades.</p>

UNCITRAL Arbitration Rules and their application in practice The purpose of the thesis is to analyse the UNCITRAL Arbitration Rules and the ways they are applied and interpreted by parties of dispute and arbitrators in international commercial arbitration. The thesis is divided into two parts. In the fist part the basic principles and legal framework of international commercial arbitration are described. Differences between institutional arbitration and ad hoc arbitration are discussed and special chapters are dedicated to permanent arbitration courts in the Czech Republic and important international arbitration institutions. Second part begins by discussion of the UNCITRAL Commission history and describes historical development of the UNCITRAL Arbitration Rules. Analysis of individual articles follows. With some articles there is established common international practice regarding their application or interpretation in international commercial arbitration. In such cases these practices and interpretations are discussed in more detail. Some articles of the revised 2010 version of the UNCITRAL Arbitration Rules are significantly different compared to the 1976 version of the UNCITRAL Arbitration Rules. These differences are analysed comparatively. Legal-analytical, legal-descriptive and legal-...

Travailler dans un contexte ad hoc et dynamique, pour les agents, empêche : 1- l'existence d'une vue globale du système qui reflète une image complète de l'environnement de déploiement ; 2- l'existence de connaissances a priori sur la manière de se coordonner en raison de l'absence d'une structure centralisée et de la disponibilité aléatoire des entités considérés. Nous avons proposé différentes stratégies comportementales pour faciliter la stabilisation dynamique des interactions entre les agents et la convergence vers les meilleurs états de coordination. Notre conception des alliances et des recommandations permet à un agent d'évoluer de manière autonome, d'identifier dynamiquement les agents voisins fiables avec qui coopérer et de former avec son voisinage des partitions Nash-stables selon les exigences de l'environnement de déploiement. Pour répondre à la difficulté de corrélation entre les comportements locaux des agents et les propriétés de l'environnement de déploiement des agents, nous utilisons de manière originale les modèles Markoviens. Nous nous sommes aussi focalisés sur la prise en compte des interdépendances entre les agents pour augmenter leur efficacité dans un souci d'optimisation les coûts imposés aux composants ad-hoc communicants où les agents sont déployés. Cela nous a amené à proposer le modèle S-NRB (Sequentiel Non-return Broadcast) et le modèle P-NRB (Parallel Non-return Broadcast) pour la coordination distribuée qui cherchent à maximiser le bien-être social des agents. Pour mettre en exergue les propriétés intrinsèques de nos méthodes, toutes nos propositions ont été étudiées de manière théorique et expérimentale grâce à notre simulateur / An ad-hoc and stochastic context prevents : 1- the existence of a global view of the system that reflects a complete image of the deployment environment ; 2- the existence of a priori knowledge because of the lack of a centralized structure, the dynamic of the tasks and the random availability of the entities. We proposed different strategies to facilitate the dynamic stabilization of the interactions between the agents and the convergence towards better coordination states. Our conception of alliances and recommendations allows an agent to evolve independently, to dynamically identify reliable neighboring agents with whom to cooperate and to form Nash-stable or Core stable coalitions according to the requirements of the deployment environment. To face with the challenges of the correlation between local behavior of the agents and the properties of their environment, we use in an original way the Markovian models. We also focused on taking into account the interdependencies between the agents to increase their efficiency in order to optimize the imputed costs of the ad-hoc components where the agents are deployed. This led us to propose both mechanisms, the S-NRB (Sequential Non-return Broadcast) and the P-NRB (Parallel Non-return Broadcast) for distributed coordination seeking to maximize the social welfare of the agents. To highlight the intrinsic properties of our methods, our whole proposals have been studied theoretically and experimentally through our simulator

Le mandat ad hoc est le nom donné à une technique ancienne, utilisée à différentes fins, pour conférer une mission particulière à une personne désignée par l'autorité judiciaire. Le terme "ad hoc", une locution latine, signifie "pour cela" et "en remplacement de". Cette expression s'applique : "à toute personne ou à tout organe à qui est assigné une mission précise et momentanée et qui reçoit des pouvoirs limités à cette fin". On retrouve ainsi dans différentes branches du droit des "mandataires" aux noms divers mais qui pourtant entrent dans la définition du mandat ad hoc : mandataire successoral, administrateur ad hoc, etc.... Une distinction entre ces différentes notions et celle de mandataire ad hoc, au sens du Livre 6 du Code de commerce, s'est alors imposée dans la présente étude puisqu'il n'existe pas un statut commun du mandataire ad hoc. Le mandat ad hoc du Livre VI du Code de commerce est issu de la pratique prétorienne du tribunal de commerce de Paris qui avait considéré qu'il entrait dans la mission du président du tribunal de commerce de faciliter la recherche d'une solution lorsqu'une entreprise éprouve des difficultés graves, d'ordre juridique, économique ou financier. Il se rapproche du mandataire ad hoc en matière de copropriété en pré-difficulté dans sa mission de négociation. Il a néanmoins été possible de dégager deux rôles essentiels des mandataires ad hoc, à savoir, un rôle de représentation et un rôle de négociation. Les réformes en cours en matière d'entreprises et de copropriétés en difficulté visent à mettre en place un véritable statut du mandataire ad hoc. Dans toutes les branches du droit, le mandataire ad hoc n'a pas de statut juridique mais simplement un embryon de statut. Cette notion de mandataire ad hoc, son succès mais également ses failles sont à mettre en exergues. La nécessité d'harmoniser les règles existantes afin de créer un statut homogène en vue de renforcer la sécurité juridique s'avère nécessaire. / The ad hoc mandate is the name given to an ancient procedure, used for different purposes, to confer a particular mission to a person designated by the judicial authority. The term "ad hoc" is a Latin expression which means "for this" and "replacement for". This term applies to "any person or a body who/which is assigned a specific and temporary mission and receives limited powers to do so"."Representatives" going by different names can therefore be found in various branches of the Law but nonetheless fall within the definition of ad hoc mandate: personal representative, ad hoc administrator, etc. A distinction between these concepts and the one of the ad hoc representative as defined in Book 6 of the Commercial Code had then to be made in the present study since there is no common status applying to ad hoc representatives. The ad hoc mandate as defined in Book VI of the Commercial Code is the result of the Praetorian practice of the Commercial Court of Paris which considered that facilitating the search for a solution when a company was experiencing serious legal, economic or financial difficulties was a mission of the President of the Commercial Court. It is similar to the role of an ad hoc representative dealing as a negotiator with pre-difficulties in condominium matters. However, it was possible to identify two essential roles of ad hoc representatives, namely the representation role and the negotiation role. Ongoing reforms concerning businesses and condominiums in difficulty aim to establish a real status for the ad hoc representative. In all branches of the Law, the ad hoc representative has no legal status per se but merely an embryo of a status. The notion of ad hoc representative, its success as well as its shortcomings has to be highlighted. It has now become a necessity to harmonize the existing rules in order to create a uniformed status so as to reinforce the judicial security.

[pt] Um avanço importante gerado pela tecnologia de TV digital é a possibilidade de interatividade com os usuários, realizada por meio do assim chamado canal de retorno. As redes ad hoc têm um grande potencial para atender esse tipo de serviço, pois podem ser empregadas em diversas áreas geográficas e idealmente de forma independente de infra- estrutura. Isso diminui o seu custo e propícia o aumento da velocidade de implantação deste tipo de rede. Uma das principais questões técnicas a serem resolvidas no contexto das redes móveis ad hoc é a necessidade de algoritmos eficientes para a realização do roteamento dos pacotes. O projeto Terminodes, desenvolvido pelo Instituto Federal de Tecnologia da Suíça, desenvolveu um protocolo de roteamento que utiliza a informação de localização. Este método de roteamento é freqüentemente proposto como um meio para prover escalabilidade em redes ad hoc distribuídas sobre áreas geográficas extensas. O roteamento baseado em localização é difícil quando há áreas de exclusão na topologia da rede e os nós são móveis ou freqüentemente desconectados para fins de economia de bateria. Portanto, a investigação da robustez do protocolo para esses casos é fundamental para avaliar seu uso em redes que podem servir como canal de retorno de TV digital. / [en] An important advance generated by the technology of digital TV is the possibility of interactivity with the users, what is done by means of the return channel. The mobile ad hoc networks have a great potential to provide this type of service, because it can ideally be used in diverse geographic areas and independent of any infrastructure. This minimizes the costs and the time needed to implement the network for this canal. One of the main questions techniques in the context of the mobile ad hoc networks is the necessity of efficient routing algorithms. The Terminodes project, developed by the Federal Institute of Technology of Switzerland, developed a routing protocol that is based in location information. This routing method frequently is a way to provide scalability in large ad hoc networks. The routing based on location is difficult when it has areas of exclusion in the topology of the network and the nodes are mobile or they are frequently disconnected to save battery. Therefore, assess the robustness of the protocol for these cases is basic to evaluate its use in networks for the digital TV return channel.

En cas de catastrophes importantes, telles qu’un tremblement de terre ou un incendie, l’efficacité des forces de la sécurité civile nécessite une bonne coordination des différents groupes d’intervention. Suivant la nature et l’importance du sinistre, l’infrastructure des moyens de communications classique peut être détruite. Les forces d’intervention ont donc besoin de nouveaux outils de communication dits réseaux de circonstance. Ces réseaux posent de nouveaux problèmes de routage, pour maintenir la connectivité, mais aussi d’allocation de ressources, particulièrement importante dans un contexte de sécurité où les communications doivent être garanties. Dans une première partie, nous avons abordé la problématique de l’allocation de ressources dans les réseaux de circonstance utilisant le partage TDMA. Nos solutions visent une répartition équitable des canaux et prennent en compte une zone d’interférence double de celle de transmission.Evaluer de nouvelles politiques dans des réseaux déployés sur des scènes de catastrophe nécessite de nouveaux modèles de mobilité. Nous avons donc également développé un nouveau modèle de mobilité spécifique au déplacement des équipes de la sécurité civile. / When a major disaster occurs, such as an earthquake or fire, the efficiency of the rescue workers depends of the coordination between the different emergency teams. This coordination needs reliable communication equipments. In such a situation, however, the infrastructure for wireless communication is generally destroyed or unusable. It is therefore necessary to find adapted communication tools for the rescue workers known as opportunistic networks. These networks pose new challenging problems such as, for instance, resource allocation which is particularly important for the QoS satisfaction. In the first part of our thesis, we addressed the problem of resource allocation in ad hoc networks using the TDMA access mechanism. Our solutions aim to perform a fair distribution of channels and take into account an interference area twice as large as the transmission range. Evaluation of new policies for opportunistic networks deployed in disaster areas requires new mobility models. We developed a novel mobility model dedicated to the movement of rescue workers. Our model includes the group mobility and some characteristics of human mobility. It also incorporates a mechanism to circumvent obstacles presents in the simulation area.

Avec le succès des communications sans fil, il devient possible d'accéder au réseau partout et à tout moment sans avoir recours à connecter physiquement les appareils communicants à une infrastructure. Les nœuds (ordinateurs portables, smartphones, etc) peuvent analyser les différents canaux radio afin de pouvoir s'associer à un réseau sans fil disponible (station de base, point d'accès, etc.). Un avantage indéniable de ses technologies sans fil est la possibilité d'être mobile tout en restant connecté. Cependant, la mobilité est une tâche difficile à gérer car elle doit être abordée à différentes couches pour être transparente aux utilisateurs. Dans les MANET (Mobile Ad hoc Network), les protocoles de routage utilisent des métriques pour sélectionner les meilleures routes. Les métriques peuvent refléter la qualité de la liaison sans fil et aider à gérer la mobilité.Mais, un retard important entre l'estimation des métriques et leur inclusion dans le processus de routage rend cette approche inefficace.Les travaux de cette thèse s'intéressent à la proposition de nouvelles méthodes de calcul des métriques de routage pour gérer le problème de la mobilité dans les réseaux ad hoc. Les nouvelles métriques doivent refléter la qualité du lien et être sensibles à la mobilité en même temps. Nous considérons les métriques classiques, en particulier ETX (Expected Transmission Count) et ETT (Expected Transmission Time). Nous introduisons de nouvelles méthodes pour anticiper les valeurs de ces métriques en utilisant des algorithmes de prédiction. Nous utilisons une approche Cross layer, qui permet l'utilisation conjointe de l'information à partir des couches 1, 2 et 3. La validation de nouvelles méthodes de calcul des métriques de routage nécessite une évaluation au travers d'un véritable banc d'essai. Nous avons donc également mis en œuvre les nouvelles métriques de routage dans un testbed afin d'évaluer et de comparer leurs performances avec les métriques classiques. / With the success of wireless communications, it becomes possible to access the network anywhere at any time without the need for physically connect communicating devices in an infrastructure. The nodes (laptops, smartphones, etc.) can analyze different radio channels to be able to associate with an available wireless network (base station, access point, etc.). An undeniable advantage of wireless technologies is the ability to be mobile while staying connected. However, mobility is difficult to manage because it must be addressed at different layers to be transparent to users. In MANET (Mobile Ad hoc Network) routing protocols use metrics to select the best routes. The metric can reflect the quality of the wireless link and help manage mobility.But a significant delay between the estimate metrics and their inclusion in the routing process makes this approach ineffective.The work of this thesis are interested in proposing new methods for calculating routing metrics to manage the problem of mobility in ad hoc networks. The new metrics should reflect the quality of the link and be sensitive to the mobility simultaneously. We consider the classical metrics, particularly ETX (Expected Transmission Count) and ETT (Expected Transmission Time). We introduce new methods to predict the values of these metrics using prediction algorithms.We use a cross layer approach, which allows the joint use of information from layers 1, 2 and 3. The validation of new methods for calculating routing metrics requires evaluation through a real bench test. So we also implemented new routing metrics in a testbed to assess and compare their performance with classical metrics.