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Apparu en 1970, le calcul parallèle permet, contrairement aux applications classiques qui exécutent un algorithme de manière séquentielle, d'exécuter des tâches d'une même application sur plusieurs processeurs en même temps. Les premières architectures -- les supercalculateurs -- qui regroupaient des milliers de processeurs au sein de la même machine, ont fait place aux grappes, à la fin des années 1970 : une interconnexion d'ordinateurs standard par un réseau rapide. Ces architectures s'étant développées un peu partout, les grilles ont fait leur apparition au début des années 1990, de manière à fédérer les ressources de différentes entités en les interconnectant et ainsi disposer d'une plus grande puissance de calcul globale. La grille, telle que nous la considérons dans ce manuscrit sera donc définie comme une interconnexion de grappes par un réseau longue distance.<br /> Les applications parallèles s'appuient la plupart du temps sur le standard MPI qui fonctionne par passage de message. Initialement destiné aux grappes, celui-ci est toujours utilisé pour programmer les communications des applications s'exécutant sur les grilles. Cela permet la réutilisation d'anciennes applications.<br /> Alors que différents problèmes ont été résolus pour les communications au sein des grappes, le réseau longue distance de la grille pose plusieurs problèmes. Tout d'abord, les messages MPI sont transmis de manière fiable sur le réseau longue distance via le protocole TCP. Or TCP, qui reste le protocole de transport utilisé dans la plupart des grilles, est basé sur un transfert de données à l'aide de flux ; il est donc peu adapté aux communications MPI. Ensuite, la grande latence du réseau longue distance implique des communications et des retransmissions de paquets perdus qui sont coûteuses. Enfin, le débit disponible sur le lien d'accès à ce réseau est généralement inférieur à la somme des débits nécessaires si tous les processus communiquent en même temps sur ce lien. Ceci crée de la congestion à la fois au sein d'une même application et à la fois avec les autres applications qui l'utilisent, et il devient nécessaire de gérer ce goulot d'étranglement.<br /> L'objectif principal de cette thèse est d'étudier en détail les interactions entre les applications parallèles et la couche de transport dans les réseaux longue distance des grilles de calcul, puis de proposer des solutions à ces problèmes.

This thesis explores how social networking sites are changing the way individuals socialize in everyday life, and how users mediate this social media. The hypothesis explored is that Facebook user’s perception of risk, when using the site, is related to how they frame the technology. Drawing on conceptual and theoretical tools from science studies and the sociologies of friendship, risk and surveillance, interview data is collected and analysed in order to identify the dynamics that structure Facebook use. It is concluded not only that, as hypothesized, participant’s awareness and perception of risk is based upon their framing of the social networking technology, but also that the framing processes arise from the technosocial hybrid nature of Facebook. That is to say, it is not exclusively based on technological possibility or on existing social practices but instead by a constant balance between the two.

Research on mental disability in the Sub-Sahara African context has recently stagnated, and is in need of a revival. The objectives of this study was to examine (i) the current situation of children and youth with mental disabilities in the Morogoro Region, Tanzania, and (ii) how to create more community awareness on rights of people with mental disabilities in the society, to put the discussion of mental disabilities back on the agenda. To fully grasp the cultural context, we have used interviews with local professionals working with children and youth with mental disabilities, in order to gain knowledge of efficient ways to create more community awareness. Over time there has been a change of attitudes due to improved knowledge, mainly through the increased visibility of people with mental disabilities in the society. However there is still a need to create awareness of the rights of people with mental disabilities, especially in rural areas. In order to influence the current situation for this group, we have concluded, within the frames of social constructionism, that networking through a bottom-up approach could be appropriate to share the burden.

<p>With the ever increasing demand for data communication methods, power line communication has become an interesting alternative method for data communication. Power line communication falls into two categories: one for data transmission between sites in the power grid and the other for home or office networking. When considering home or office networking, existing methods are either too slow for tasks other than simple automation, or are very fast with a higher cost than necessary for the desired function. The objective in this work is to develop a lower cost communication system with an intermediate data transmission rate.</p><p>At first glance, power line communication looks like a good option because of the availability of power outlets in every room of a building. However, the power conductors were installed solely for the purpose of distributing 60 Hz mains power and, for data signals, they exhibit very high attenuation, variable impedance and there is radio frequency shielding. Furthermore, many of the 60 Hz loads produce radio frequency interference that impedes data communication. Previous research has shown that much of the noise is time synchronous with the 60 Hz mains frequency and that the majority of data errors occur during these periods of high noise.</p><p> This work develops a power line communication protocol that coordinates transmissions and uses only the predictable times of lower noise. Using a central control strategy, the power line 60 Hz mains signal is divided into 16 timeslots and each timeslot is monitored for errors. The central controller periodically polls all stations to learn which timeslots have low noise and it then controls all transmissions to make the best use of these good timeslots. The periodic polling allows the system to adapt to changes in electrical loading and noise. This control strategy has been achieved with modest complexity and laboratory measurements have shown throughput approaching 70% of the modem bit rate.</p>

Les communications sont difficiles à maintenir dans les réseaux informatiques quand ils sont dynamiques. Les réseaux de véhicules sont un exemple direct de ces réseaux ad hoc dynamiques. Dans ce manuscrit, nous nous intéressons aux communications unicast dans les réseaux ad hoc dynamiques (réseaux véhiculaires en particulier). Nous avons effectué des tests sur route afin d'analyser les performances de ces réseaux. Les résultats nous ont permis de proposer des améliorations aux communications V2I et V2V. Vue l'étude des performances, nous avons opté pour une architecture opportuniste pour les communications V2I (remontée des données du réseau véhiculaire vers l'infrastructure via une passerelle). Pour les communications V2V, la source et la destination sont mobiles. La communication est alors menacée d'être interrompue. Nous proposons un algorithme de maintien de chemin qui garantit l'acheminement des messages entre les deux entités en mouvement dans le réseau. Cet algorithme utilise les échanges locaux pour ajuster le chemin, et s'affranchit ainsi de la dynamique du réseau. Pour mieux comprendre les limites du routage en général et de notre algorithme de maintien de chemin en particulier, nous utilisons l'approche " best effort " qui formalise un compromis entre la dynamique du réseau et les propriétés d'un algorithme. Nous introduisons les graphes p-dynamiques pour caractériser la dynamique. Ils permettent alors d'exprimer une propriété dite topologique, qui est nécessaire pour garantir une propriété dite de continuité du service offert par l'algorithme. Cette approche de modélisation constitue un premier pas vers une métrique algorithmique de la dynamique des réseaux.

This thesis explores how social networking sites are changing the way individuals socialize in everyday life, and how users mediate this social media. The hypothesis explored is that Facebook user’s perception of risk, when using the site, is related to how they frame the technology. Drawing on conceptual and theoretical tools from science studies and the sociologies of friendship, risk and surveillance, interview data is collected and analysed in order to identify the dynamics that structure Facebook use. It is concluded not only that, as hypothesized, participant’s awareness and perception of risk is based upon their framing of the social networking technology, but also that the framing processes arise from the technosocial hybrid nature of Facebook. That is to say, it is not exclusively based on technological possibility or on existing social practices but instead by a constant balance between the two.

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Kunskapsöverföring har ansetts vara av vikt inom företag och organisationer för att bevara kunskapen, informationen och för att kunna förmedla den vidare till andra medlemmar. Studiens primära syfte var att genom forskningsteorier och intervjuer effektivisera Rädda barnens Ellen och Allan projekt i deras kunskapsöverföring. 5 aktiva medlemmar inom Ellen och Allan projektet intervjuades samt 1 kontrollintervju genomfördes med en rutinerad projektledare från Svenska kyrkan, för att få fram dennes syn på projektets nuvarande situation gällande kunskapsöverföring.      Resultatet visade att det finns en viss otrygghet i rollerna och framförallt hos projektledarna, som inte har någon specifik roll- eller uppdragsbeskrivning. Genom resultatet kunde vi även se att kunskapsöverföringen bör vara ett ingående moment i organisationens projektbeskrivning för att det ska fungera på bästa sätt. Fysiska möten och god kommunikation mellan deltagarna bör även prioriteras för att effektivisera kunskapsöverföringen inom projektet.

Abstract Title: Relationships management in hospitality industry, STF Svenska   Touristförening.   Level: Final assignment for Master Degree in Business Administration   Author: Aleksandr Shalimov , Calistus Godwin   Supervisor: Ernst Hollander   Date: 2013.01   Aim:  The aim of the research is to investigate STF relationships management strategy and networking ability. This research illuminates conceptual understanding of the STF’s network and relationships management strategy.    Method: In order to provide answers to the research question was used case study approach. Qualitative research method was applied, face to face interviews were conducted and in some cases email and telephone interviews was also used. Using cluster sampling, 9 people who have different backgrounds and relations to STF was interviewed. To properly analyze and present this complex relationships phenomenon, narrative approach was used, considered to be the most appropriate to work with, due to the huge amount of qualitative data.   Result &amp; Conclusions: The research showed the existence of complex relationships between STF (Svenska Touristförenengen) and different actors that are involved with STF within its market activities. Companies that are involved in the STF network, at the same time involved in the process of management of relationships, activities and network structure. Development of the network depends on the companies’ abilities to develop mutual relationships (network threads). This requires understanding of the company’s network and abilities to form network. The development of relationships management strategy is the core competence of the STF. In conclusion, looking at all the relationship that STF has built, it could be said that all have being focal to its network building but to a varying degree.  Moreover within applied the study, it was noticed that STF during its 125 years of existence, has facilitated the development of tourism, infrastructure, business, sports, education, and cultural life of the country. It has created and developed social and economic relations, and communication channels. STF plays the role of an initiator, originator, pioneer and cooperator, even as a fellow worker in creating national movements and new trends.   Suggestions for future research: The investigation has been started having in mind Relationships, Outsourcing and Networking theories as anchor theories to be used, but after a while, it turned out that Networking theory and Franchising theory could be used to investigate deeply into the relationships phenomenon with the actors in this case.  But still within the research, it was noticed that some aspects of franchising model was not working properly and sometimes do not meet both STF and Franchisee`s expectations. Therefore suggestion for closer and deeper investigations of relationships pattern between STF and its franchisees is recommended in order to facilitate the development of more viable, functional and effective ways of cooperation. Moreover triangulation is a strategy that increases the validity and reliability of research, so it could be considered for the further research.     Contribution of the thesis: Currently, under the influence of globalization in the social and economic environment, more and more attention is being paid to the study of various relationships and communications theories, for example the development of CRM, Outsourcing and Networking theories. This study involves a closer look on some aspects of the interaction of social and economic environment, particularly the development of social and business networks. The concept of STF could be used to develop other business ideas or even exported to emerging markets, base on a successful strategic implementation of the concept. STF pattern of activities shows that the creation of such organizations as STF and investigative related issues, may contribute to the development of the tourism industry both nationally and internationally. To STF and the Swedish Tourism Board, (tillvexverkert) researches could help in a lot ways by encouraging more research work to improve and better the already existing infrastructures, improve on the services and communications channels.   Key words: STF (Svenska Touristförening), Networking, Relationships, Hospitality Industry, Tourism, Association.