La nouvelle génération de réseaux mobiles (5G) devrait faire face, durant les cinq prochaines années, à une importante croissance du volume de données, échangé entre plusieurs milliards d'objets et d'applications connectés. En outre, l'émergence de nouvelles technologies, telles que Internet of Things (IoT), conduite autonome et réalité augmentée, impose de plus fortes contraintes de performance et de qualité de service (QoS). Répondre aux besoins cités, tout en réduisant les dépenses d'investissement et d'exploitation (CAPEX/OPEX), sont les objectifs poursuivis par les opérateurs télécom, qui ont défini une nouvelle architecture d'accès radio, appelée Cloud Radio Access Network (C-RAN). Le principe du C-RAN est de centraliser, au sein d'un pool, les parties de traitement, BaseBand Unit (BBU), d'un RAN traditionnel. Les BBU sont alors dissociées de la station de base et de la partie radio, Remote Radio Unit (RRU). Ces deux parties restent néanmoins connectées à travers un réseau intermédiaire appelé Fronthaul (FH). Dans cette thèse, nous allons concevoir une nouvelle architecture C-RAN partiellement centralisée qui intègrera une plateforme de virtualisation basée sur un environnement Xen, nommée " Metamorphic Network " (MNet). A travers cette architecture, nous viserons à : i) mettre en place un pool, dans lequel des ressources physiques (processeurs, mémoire, ports réseaux, etc.) seront partagées entre des BBU virtualisées et d'autres applications, ii) établir un réseau FH ouvert aux fournisseurs de services et aux tierces parties, facilitant ainsi le déploiement des services au plus près des utilisateurs, pour une meilleure qualité d'expérience, iii) exploiter, à travers le FH, les infrastructures Ethernet existantes pour réduire les CAPEX/OPEX et enfin, iv) atteindre les performances réseau préconisées pour la 5G. Dans la première contribution, nous allons définir une nouvelle architecture Xen pour la plateforme MNet, intégrant le framework de packet processing, OpenDataPlane (ODP), au sein d’un domaine Xen privilégié, nommé « Driver Domain ». Notre objectif, à travers cette architecture, est d’accélérer le traitement des paquets de données transitant par MNet, en évitant la surutilisation, par ODP, des cœurs du processeur physique (CPU) de la plateforme. Pour cela, des cœurs CPU virtuels (vCPU) seront alloués dans le Driver Domain pour être exploités durant le traitement des paquets par ODP. Cette nouvelle plateforme MNet servira de base pour notre architecture C-RAN. Dans la seconde contribution, nous allons implémenter, au sein du FH, deux solutions réseau. La première solution, consistera à déployer le réseau de couche 2, Transparent Interconnection of Lots of Links (TRILL), pour connecter les différents éléments de notre architecture C-RAN. La seconde solution, consistera à déployer un réseau Software Defined Network (SDN), géré par le contrôleur distribué ONOS, qui sera virtualisé dans le pool BBU. Une comparaison des performances réseau sera réalisée entre ces deux solutions. / Over the next five years, the new generation of mobile networks (5G) would face a significant growth of the data volume, exchanged between billions of connected objects and applications. Furthermore, the emergence of new technologies, such as Internet of Things (IoT), autonomous driving and augmented reality, imposes higher performance and quality of service (QoS) requirements. Meeting these requirements, while reducing the Capital and Operation Expenditures (CAPEX/OPEX), are the pursued goals of the mobile operators. Consequently, Telcos define a new radio access architecture, called Cloud Radio Access Network (C-RAN). The C-RAN principle is to centralize, within a pool, the processing unit of a radio interface, named BaseBand Unit (BBU). These two units are interconnected through a Fronthaul (FH) network. In this thesis, we design a new partially centralized C-RAN architecture that integrates a virtualization platform, based on a Xen environment, called Metamorphic Network (MNet). Through this architecture, we aim to: i) implement a pool in which physical resources (processors, memory, network ports, etc.) are shared between virtualized BBUs and other applications; ii) establish an open FH network that can be used by multiple operators, service providers and third parties to deploy their services and Apps closer to the users for a better Quality of Experience (QoE); iii) exploit, through the FH, the existing Ethernet infrastructures to reduce CAPEX/OPEX; and finally iv) provide the recommended network performance for the 5G. In the first contribution, we define a new Xen architecture for the MNet platform integrating the packet-processing framework, OpenDataPlane (ODP), within a privileged Xen domain, called Driver Domain (DD). This new architecture accelerates the data packet processing within MNet, while avoiding the physical CPUs overuse by ODP. Thus, virtual CPU cores (vCPU) are allocated within DD and are used by ODP to accelerate the packet processing. This new Xen architecture improves the MNet platform by 15%. In the second contribution, we implement two network solutions within the FH. The first solution consist of deploying a layer 2 network protocol, Transparent Interconnection of Lots of Links (TRILL), to connect multiple elements of our C-RAN architecture. The second solution consists of implementing a Software Defined Network (SDN) model managed by Open Network Operating System (ONOS), a distributed SDN controller that is which is virtualized within BBU pool. Moreover, a network performance comparison is performed between these two solutions.

Este trabalho de pesquisa aprofunda o conhecimento associado aos sistemas de automação modernos baseados em redes de controle LonWorks®, visando torná-los mais facilmente utilizáveis como meios de implementar ambientes pervasivos. Para tanto, foi proposto um modelo de relacionamento dinamicamente reconfigurável entre dispositivos de uma rede de controle, que permite conferir a um sistema de automação distribuído algumas características previstas na computação pervasiva. É proposta uma extensão do modelo de objetos na tecnologia LonWorks®, utilizando conceitos de middleware, de forma a conferir aos módulos da rede a capacidade de auto-gerenciamento dinâmico, de modo a modificar os seus comportamentos à medida que novas situações sejam identificadas. A extensão proposta foi aplicada experimentalmente, visando a sua validação e refinamento, como o sistema de comunicação interno de uma empresa, substituindo os PABXs convencionais, considerado em maiores detalhes. Constatou-se a impossibilidade de sua implementação com a tecnologia LonWorks® atual, que utiliza conexões estáticas, necessitando de um operador ou integrador para configurá-las, caso não seja adotada a extensão proposta. Como estudo de caso o projeto de um PABX baseado na tecnologia LonWorks® foi avaliado e discutido, contribuindo para a geração de uma nova metodologia de concepção de sistemas de automação que possam atender algumas propostas previstas na computação pervasiva. É proposto integrar a Tecnologia da Informação e Comunicação, com as ações e os comportamentos convencionais que as pessoas apresentam. Essa metodologia proposta supera os desafios de projetistas de sistemas de automação de ambientes, em especial os prediais, e obtém integração entre processos de forma que as pessoas não percebam que estão interagindo com um computador, cuja presença deverá cada vez mais se tornar onipresente. Além de facultar interfaces fáceis e naturais, tem-se também a incorporação dos conceitos da computação sensível a contexto nos sistemas de automação. / Pervasive or ubiquitous computing, proposes the integration between the information and communication technology with the actions and common behaviors presented by people. One of the challenges that it imposes to the environmental automation systems developers, specially building automation developers, is that this integration is processed in such a way that people do not realize they are interacting with a computer, thus its presence becomes omnipresent. Besides the need of an easy and natural interface, there is also the need to incorporate the sensitive computing context to the automation systems. The current control networks utilized in automation systems, building, home and industrial control do not show resources that support the requirements of pervasive computing. This research intend to improve the knowledge associated to modern automation systems, based on LonWorks® control networks, viewing to make them more easily usable as ways to implement pervasive environments. For that, a dynamically settable relationship model was proposed between the intelligent devices of a control network, which allows providing some foreseen characteristics on pervasive computing in a distributed automation system. A LonWorks® technology object model extension is proposed, using middleware concepts, in a dynamic way, to modify behaviors when new situations are identified. The proposed extension was experimentally applied to a few use cases, aiming at its validation and refinement, such as the internal communication of a company, which replaces the usual PABX, which was considered in greater detail. The impossibility of its implementation was found with the current technology, without the use of the proposed extension. Those cases were evaluated and discussed, contributing to a new automation system concept technology that can support provided proposals on pervasive computing.

Este trabalho de pesquisa aprofunda o conhecimento associado aos sistemas de automação modernos baseados em redes de controle LonWorks®, visando torná-los mais facilmente utilizáveis como meios de implementar ambientes pervasivos. Para tanto, foi proposto um modelo de relacionamento dinamicamente reconfigurável entre dispositivos de uma rede de controle, que permite conferir a um sistema de automação distribuído algumas características previstas na computação pervasiva. É proposta uma extensão do modelo de objetos na tecnologia LonWorks®, utilizando conceitos de middleware, de forma a conferir aos módulos da rede a capacidade de auto-gerenciamento dinâmico, de modo a modificar os seus comportamentos à medida que novas situações sejam identificadas. A extensão proposta foi aplicada experimentalmente, visando a sua validação e refinamento, como o sistema de comunicação interno de uma empresa, substituindo os PABXs convencionais, considerado em maiores detalhes. Constatou-se a impossibilidade de sua implementação com a tecnologia LonWorks® atual, que utiliza conexões estáticas, necessitando de um operador ou integrador para configurá-las, caso não seja adotada a extensão proposta. Como estudo de caso o projeto de um PABX baseado na tecnologia LonWorks® foi avaliado e discutido, contribuindo para a geração de uma nova metodologia de concepção de sistemas de automação que possam atender algumas propostas previstas na computação pervasiva. É proposto integrar a Tecnologia da Informação e Comunicação, com as ações e os comportamentos convencionais que as pessoas apresentam. Essa metodologia proposta supera os desafios de projetistas de sistemas de automação de ambientes, em especial os prediais, e obtém integração entre processos de forma que as pessoas não percebam que estão interagindo com um computador, cuja presença deverá cada vez mais se tornar onipresente. Além de facultar interfaces fáceis e naturais, tem-se também a incorporação dos conceitos da computação sensível a contexto nos sistemas de automação. / Pervasive or ubiquitous computing, proposes the integration between the information and communication technology with the actions and common behaviors presented by people. One of the challenges that it imposes to the environmental automation systems developers, specially building automation developers, is that this integration is processed in such a way that people do not realize they are interacting with a computer, thus its presence becomes omnipresent. Besides the need of an easy and natural interface, there is also the need to incorporate the sensitive computing context to the automation systems. The current control networks utilized in automation systems, building, home and industrial control do not show resources that support the requirements of pervasive computing. This research intend to improve the knowledge associated to modern automation systems, based on LonWorks® control networks, viewing to make them more easily usable as ways to implement pervasive environments. For that, a dynamically settable relationship model was proposed between the intelligent devices of a control network, which allows providing some foreseen characteristics on pervasive computing in a distributed automation system. A LonWorks® technology object model extension is proposed, using middleware concepts, in a dynamic way, to modify behaviors when new situations are identified. The proposed extension was experimentally applied to a few use cases, aiming at its validation and refinement, such as the internal communication of a company, which replaces the usual PABX, which was considered in greater detail. The impossibility of its implementation was found with the current technology, without the use of the proposed extension. Those cases were evaluated and discussed, contributing to a new automation system concept technology that can support provided proposals on pervasive computing.

Vatten är ett livsmedel som vi kommer i kontakt med dagligen. För att inte råka ut för sjuk-domar och infektioner renas dricksvattnet på vattenverken, främst för att reducera antalet patogener, d.v.s. sjukdomsframkallande mikroorganismer. Man brukar prata om tre grupper mikroorganismer i vattenrening; bakterier, virus och parasiter. Dessa grupper är vitt skilda i många avseenden och reduceras därför olika bra av olika reningssteg. Ju mer kunskap man kan få om reningsprocessen, desto bättre kan reningen optimeras. Därmed minimeras riskerna för konsumenterna att drabbas av infektioner. I det här arbetet används två modeller för att beskriva och utvärdera Borgs vattenverk som drivs av Norrköping Vatten AB. Modellen God desinfeksjonspraksis (GDP) är ett resultat av ett norskt projekt och baserar sig på formler och tabeller. Först avgörs råvattenkvaliteten genom att vattenverkets storlek och förekomst av mikroorganismer bedöms. Därefter görs diverse avdrag för förebyggande åtgärder, rening utöver desinfektion m.m. Slutligen bedöms desinfektionsgraden genom att det tillsatta klorets avklingning bestäms för beräkning av Ct-värdet; produkten av kontakttiden och koncentrationen. Genom att jämföra råvattenkvaliteten med avdragen och desinfektions-graden kan en bedömning göras om huruvida reningsprocessen är tillräcklig eller inte. I Mikrobiologisk riskanalys (MRA) bygger man upp en modell av sitt vattenverk i ett program och väljer patogenhalter för råvattnet. Efter det beräknar programmet renings-processens reduktion, riskerna för daglig respektive årlig sannolikhet för infektion samt DALYs, som gör att man kan jämföra risken för vattenburen smitta med exempelvis risken att förolyckas i trafiken. Det amerikanska naturvårdsverket och WHO har satt gränsen för den acceptabla årliga sannolikheten för infektion på grund av vattenrelaterad sjukdom till 1/10 000 invånare respektive 1 µDALYs. Fördelen med MRA är att när man väl byggt upp sitt vattenverk i programmet kan olika scenarion simuleras genom att patogenhalterna varieras. Tyvärr är det svårt att uppskatta patogenhalterna då de provtagningar som skulle behövas sällan är gjorda. Även litteraturvärden kan vara svårt att hitta, särskilt för virus som är så små att de är svåra att analysera. Resultatet av bägge modellerna visade på att Borgs vattenverks reduktionsförmåga är tillräcklig med avseende på bakterier, men inte för virus och parasiter. I MRA är det emellertid svårt att säga hur korrekt detta påstående är, då endast litteraturvärden kunnat användas för de två sistnämnda patogenerna. En del provtagningar har gjorts och då har inga parasiter kunnat påvisas i råvattnet, men för att inte underskatta riskerna användes litteratur-värdena ändå. GDP påvisade inga stora brister i reduceringen av virus och parasiter och i MRA låg resultatet i samma storleksordning som gränsen för DALYs. Eventuellt behöver alltså inga stora åtgärder vidtas för att minska de mikrobiologiska riskerna. De viktigaste stegen i reningsprocessen är långsamfiltrering, desinfektion med fritt klor och fällning och sedimentering med efterföljande filtrering. Infektionsrisken blir störst om fällningssteget slås ut. I samtliga simulerade scenarion låg infektionssannolikheten för bakterier fortfarande på en acceptabel nivå. Det värsta scenariot av de modellerade är om avloppsledningen från Skärblacka skulle börja läcka samtidigt som det regnar kraftigt. Det skulle leda till att förorening från betesmark spolas med ut i Motala Ström där råvattnet hämtas. Detta ger den högsta patogenhalten och därmed också den största infektionsrisken. / Water is one of the most basic things in life and is something we come in contact with on a daily basis. To prevent diseases and infections, the drinking water is purified, mainly in order to reduce the number of pathogens. The most important groups of microorganisms in water purification are bacteria, viruses, and parasites. These groups are very different in many respects and are therefore reduced most efficiently by different purification processes. If more knowledge is gained, the waterworks can optimize the purification process. This would lead to a minimization of the risk of getting infections caused by consuming the drinking water. In this paper two models are used to describe and evaluate Borg’s waterworks, run by Norrköping Vatten AB. Good Disinfection Practice (GDP) is the result of a Norwegian project and is based on formulas and tables. First, the raw water quality is determined by evaluating the presence of microorganisms and the number of people supplied. Then deductions are made due to security precautions and water treatment besides disinfection etc.  Finally the disinfection is determined by calculating the reduction of the added chlorine to gain the Ct-value, which is the product of the contact time and concentration. By comparison of the raw water, the deductions and the disinfection, the purification process can be evaluated as sufficient or not. In Quantitative Microbial Risk Assessment (QMRA) the purification process is modelled and concentrations of pathogens in the raw water are chosen. The program then calculates the reduction of the pathogens by the purification process. The result is also presented as probability of daily or annual infection and DALYs, which makes it possible to compare the risks of waterborne diseases with for example, the risk of traffic accidents. The US Environmental Protection Agency and the World Health Organization have determined the limit for the acceptable annual probability of infection due to water-related disease to 1/10,000 and 1 µDALYs. The advantage of the QMRA is that once you have modelled your purification process a variety of scenarios can be simulated. Unfortunately, it is difficult to estimate the concentrations of pathogens in the raw water and the acquired analysis are rarely made. Even literature values can be difficult to find, especially for viruses due to the difficulties in analysing them because of their small size. Both the models’ results showed that Borg’s waterworks reduction capacity is sufficient for bacteria, but not viruses and parasites. It is however difficult to say how accurate this conclusion is. In QMRA only literature values have been used as a basis to determine the risk for viruses and parasites. In fact, no parasites have been found when samples have been run on the raw water. But since an overestimation of the risk is to be preferred, literature values were used anyway. GDP showed only small shortcomings in the reduction of viruses and parasites and the values obtained from QMRA were in the same order of magnitude as the limit of DALYs. Therefore only small measures might be needed to lower the microbiological risks. The most important steps in the purification process are slow sand filtration, disinfection with free chlorine and precipitation and sedimentation with subsequent filtering. Elimination of the precipitating step results in the greatest risk of infection. In all the scenarios simulated the likelihood of infections caused by bacteria is still acceptable.  The worst-case scenario would be a sewage water leak during heavy raining. The rain would cause excrement from cattle to be washed into and contaminate the raw water in addition to the sewage contamination. This provides the highest concentration of pathogens in the raw water and therefore also the greatest risk of infection.

A importância do Estado de São Paulo (ESP) é notável no desenvolvimento do Brasil, seja no setor econômico ou energético, o que justifica o estudo do comportamento do clima nessa região. O conhecimento da variabilidade da precipitação é imprescindível na gestão de recursos hídricos e possui grande impacto na agricultura e geração de energia por meio de fontes hidrelétricas. Estudos anteriores apontaram efeitos não-lineares do El Niño-Oscilação Sul (ENOS) sobre a precipitação no ESP; entretanto, nenhum estudo específico acerca da influência da Oscilação interdecadal do Pacífico (ODP) nesta área foi ainda realizado, embora haja alguns impactos conhecidos na América do Sul. Deste modo, este trabalho estudou a relação entre anomalias de precipitação no ESP e a ODP, no período de 1901 a 2007, de forma a auxiliar as pesquisas na linha da previsão climática nessa região do Brasil. Na primeira etapa, foram descritos os regimes de precipitação tanto para a América do Sul como localmente, para o ESP, onde se destacaram fatores como a topografia e a influência do Oceano Atlântico. Posteriormente, foram calculados quantis anuais e mensais que permitiram classificar cada evento quanto ao total de precipitação. Regiões pluviometricamente homogêneas foram determinadas no ESP com base na climatologia e nos quantis de precipitação. Notou-se a relação construtiva entre eventos ENOS e as fases da ODP, com máximo durante o verão austral. Os sinais da ODP são percebidos em todo o ESP principalmente na primavera e no verão austrais. Uma análise complementar mostrou que as fases da Oscilação Multidecadal do Atlântico (AMO) também contribuem para a precipitação no ESP durante o verão e a primavera austrais no litoral, durante o verão no interior, e ao longo da primavera na região da Serra da Mantiqueira. Aparentemente, não há relação entre os eventos ENOS e a AMO. / São Paulo State (SPS) is remarkably important to the development of Brazil, economically or energetically, and this justifies climate studies on that region. Knowing rainfall variability is essential to water resources management and it has a great impact on agriculture an power production by hydroelectric power plants. Previous studies have detected non-linear effects of El Niño-Southern Oscillation (ENSO) on SPS rainfall however no specific work deals with PDO influence in this area besides some impacts on South America are known. Therefore this work has studied the relationship between rainfall anomalies in SPS and PDO from 1901 to 2007 to contribute to the climate forecasting improvement. First it was described the rainfall regime in South America, and locally in SPS where topography and the Atlantic Ocean influences were of special importance. Then annual and monthly quantiles were calculated to allow the classification of events according to rainfall totals. Rainfall homogeneous regions were established in SPS using climatology and quantiles. It was observed the constructive relationship between ENSO events and PDO phases, mainly on austral summer. PDO signals were noticed all over the SPS mostly on austral spring and summer. An additional analysis showed that Atlantic Multidecadal Oscillation (AMO) phases also contribute to SPS rainfall during austral summer and spring at the coast, only on summer at the country and during spring at the Mantiqueira Slopes. Apparently, there is no relation between ENSO events and AMO phases.

I resolved the sedimentary architecture of a shallow water (< 500 m), hemipelagic sediment drift located on the Marion Plateau, seaward and downstream of the Great Barrier Reef (GBR). The drift responded increasingly to sea-level fluctuations during the Pleistocene. In the early Pleistocene, local climatic variations introduce a precessional rhythm to drift architecture that is out of phase with sea level-forced cyclicity. Beginning in the mid Pleistocene, sea level variations dominate drift architecture, with the highest carbonate and terrigenous fluxes likely occurring during highstand and transgression, respectively. At the sea-level transgression of MIS 15 and subsequent isotope stages, the phasing of maximum terrigenous flux corresponds to sea-level transgression, indicating siliciclastic sediment accumulated on the continental shelf behind an exposed barrier reef during the lowstand of MIS 16 and was remobilized by rising sea-level. These sedimentological data indicate GBR initiation occurred during MIS 17. The normal polarity exhibited by the central GBR and thick section of underlying sediments rules out initiation during MIS 19. MIS 17 was the first of the asymmetric glacial cycles characteristic of the Late Pleistocene. If the Florida Keys and Belize barrier reef initiations were indeed simultaneous with that of the GBR, then the changing nature of cyclicity in global sea level and climatic fluctuations likely influenced the initiation of the world's major, modern barrier reefs.

With the exponential growth of the Web and the inherent polysemy and synonymy problems of the natural languages, search engines are facing many challenges such as information overload, mismatch of search results, missing relevant documents, poorly organized search results, and mismatch of human mental model of clustering engines. To address these issues, much effort including employing different information retrieval (IR) models, information categorization/clustering, personalization, semantic Web, ontology-based IR, and so on, has been devoted to improve the relevance of search results. The major focus of this study is to dynamically re-organize Web search results under a socially constructed hierarchical knowledge structure, to facilitate information seekers to access and manipulate the retrieved search results, and consequently to improve the relevance of search results. / To achieve the above research goal, a special search-browser is developed, and its retrieval effectiveness is evaluated. The hierarchical structure of the Open Directory Project (ODP) is employed as the socially constructed knowledge structure which is represented by the Tree component of Java. Yahoo! Search Web Services API is utilized to obtain search results directly from Yahoo! search engine databases. The Lucene text search engine calculates similarities between each returned search result and the semantic characteristics of each category in the ODP; and thus to assign the search results to the corresponding ODP categories by Majority Voting algorithm. When an interesting category is selected by a user, only search results categorized under the category are presented to the user, and the quality of the search results is consequently improved. / Experiments demonstrate that the proposed approach of this research can improve the precision of Yahoo! search results at the 11 standard recall levels from an average 41.7 per cent to 65.2 per cent; the improvement is as high as 23.5 per cent. This conclusion is verified by comparing the improvements of the P@5 and P@10 of Yahoo! search results and the categorized search results of the special search-browser. The improvement of P@5 and P@10 are 38.3 per cent (85 per cent - 46.7 per cent) and 28 per cent (70 per cent - 42 per cent) respectively. The experiment of this research is well designed and controlled. To minimize the subjectiveness of relevance judgments, in this research five judges (experts) are asked to make their relevance judgments independently, and the final relevance judgment is a combination of the five judges’ judgments. The judges are presented with only search-terms, information needs, and the 50 search results of Yahoo! Search Web Service API. They are asked to make relevance judgments based on the information provided above, there is no categorization information provided. / The first contribution of this research is to use an extracted category-document to represent the semantic characteristics of each of the ODP categories. A category-document is composed of the topic of the category, description of the category, the titles and the brief descriptions of the submitted Web pages under this category. Experimental results demonstrate the category-documents of the ODP can represent the semantic characteristics of the ODP in most cases. Furthermore, for machine learning algorithms, the extracted category-documents can be utilized as training data which otherwise demand much human labor to create to ensure the learning algorithm to be properly trained. The second contribution of this research is the suggestion of the new concepts of relevance judgment convergent degree and relevance judgment divergent degree that are used to measure how well different judges agree with each other when they are asked to judge the relevance of a list of search results. When the relevance judgment convergent degree of a search-term is high, an IR algorithm should obtain a higher precision as well. On the other hand, if the relevance judgment convergent degree is low, or the relevance judgment divergent degree is high, it is arguable to use the data to evaluate the IR algorithm. This intuition is manifested by the experiment of this research. The last contribution of this research is that the developed search-browser is the first IR system (IRS) to utilize the ODP hierarchical structure to categorize and filter search results, to the best of my knowledge.

Ce travail de thèse propose un cadre méthodologique pour l'ingénierie et la réingénierie de la formation à distance qui s'appuie sur les récents efforts de normalisation des technologies éducatives. Ce cadre s'adresse aux concepteurs, afin de les accompagner dans leur travail, et de favoriser l'acquisition de nouvelles connaissances et compétences, notamment d'ordre conceptuel, organisationnel et méthodologique. En amenant les concepteurs à spécifier de manière explicite leurs intentions de conception d'un système de formation dans des modèles, et en confrontant ces modèles de spécification avec les usages observés durant les sessions d'apprentissage, nous accompagnons la nécessaire démarche réflexive de l'équipe de conception sur ses méthodes, et favorisons le développement et la capitalisation des savoir-faire et des démarches pédagogiques au sein d'une communauté de concepteurs.<br /><br />Nous avons proposé le cadre de référence du processus distribué ouvert de l'ISO (International Organization for Standardization) et de l'IEC (International Electrotechnical Commission) comme le méta-standard à adresser aux concepteurs de la communauté EIAH. La vision globale d'un système est explicitée par des mécanismes de transformations de différents points de vue.<br /><br />Un tel cadre a pour intérêt d'adresser un ensemble de termes à la communauté de concepteurs soucieux de partager les pratiques. Ce vocabulaire permet d'expliciter les invariants et les principes généraux, structuraux et fonctionnels d'un système de formation. Le travail présenté dans cette thèse vise à définir différentes instances d'un tel méta-standard et à illustrer ainsi les différents apports de ce modèle à la communauté des concepteurs des EIAH. La présentation du travail se structure autour de trois analyses instrumentées par le cadre ODP-RM (Object Distributed Processsing - Reference Model), trois réflexions sur la conception d'un EIAH portant sur l'utilisation des technologies éducatives normées, sur la réingénierie dans les EIAH et sur le processus de développement dirigé par les modèles. Les illustrations présentées dans le mémoire montrent le potentiel du cadre choisi à formaliser ces différents constats et à créer un ensemble d'instances décrivant de nouveaux éléments méthodologiques à adresser à la communauté de concepteurs d'un système de formation.

Carbonate preservation in the oceans occurs at a depth called the carbonate compensation depth (CCD). The CCD is where the input rate of carbonate from the surface of the ocean is balanced by the dissolution rate. Factors controlling the CCD are the CO2 in the atmosphere, weathering, and productivity in the surface water, the depth of the lysocline and deep water currents (and their ocean circulation). Two previous studies have investigated the variation of the CCD through geologic time, one in the equatorial Pacific (Pälike et al., 2012) and the other compiled results from the Pacific, Atlantic and Indian Oceans (Van Andel, 1975). The project consisted of compiling a database of sediment lithologies for many more sites in the Atlantic since the compilation by Van Andel, 1975, and together with a subsidence model of the ocean crust the systematic variations of CCD could be investigated. The results show that the CCD varies both spatially and temporally in accordance with previous studies. The reconstruction of the CCD needs further analysis, and possibly data from the oldest drilling program, the Deep Sea Drilling Project (DSDP). One result that is very important is that this study includes a total of 91 sites in the Atlantic Ocean, far more than in any of the other two studies. Future work can build upon the already started database of sediment lithologies.

A importância do Estado de São Paulo (ESP) é notável no desenvolvimento do Brasil, seja no setor econômico ou energético, o que justifica o estudo do comportamento do clima nessa região. O conhecimento da variabilidade da precipitação é imprescindível na gestão de recursos hídricos e possui grande impacto na agricultura e geração de energia por meio de fontes hidrelétricas. Estudos anteriores apontaram efeitos não-lineares do El Niño-Oscilação Sul (ENOS) sobre a precipitação no ESP; entretanto, nenhum estudo específico acerca da influência da Oscilação interdecadal do Pacífico (ODP) nesta área foi ainda realizado, embora haja alguns impactos conhecidos na América do Sul. Deste modo, este trabalho estudou a relação entre anomalias de precipitação no ESP e a ODP, no período de 1901 a 2007, de forma a auxiliar as pesquisas na linha da previsão climática nessa região do Brasil. Na primeira etapa, foram descritos os regimes de precipitação tanto para a América do Sul como localmente, para o ESP, onde se destacaram fatores como a topografia e a influência do Oceano Atlântico. Posteriormente, foram calculados quantis anuais e mensais que permitiram classificar cada evento quanto ao total de precipitação. Regiões pluviometricamente homogêneas foram determinadas no ESP com base na climatologia e nos quantis de precipitação. Notou-se a relação construtiva entre eventos ENOS e as fases da ODP, com máximo durante o verão austral. Os sinais da ODP são percebidos em todo o ESP principalmente na primavera e no verão austrais. Uma análise complementar mostrou que as fases da Oscilação Multidecadal do Atlântico (AMO) também contribuem para a precipitação no ESP durante o verão e a primavera austrais no litoral, durante o verão no interior, e ao longo da primavera na região da Serra da Mantiqueira. Aparentemente, não há relação entre os eventos ENOS e a AMO. / São Paulo State (SPS) is remarkably important to the development of Brazil, economically or energetically, and this justifies climate studies on that region. Knowing rainfall variability is essential to water resources management and it has a great impact on agriculture an power production by hydroelectric power plants. Previous studies have detected non-linear effects of El Niño-Southern Oscillation (ENSO) on SPS rainfall however no specific work deals with PDO influence in this area besides some impacts on South America are known. Therefore this work has studied the relationship between rainfall anomalies in SPS and PDO from 1901 to 2007 to contribute to the climate forecasting improvement. First it was described the rainfall regime in South America, and locally in SPS where topography and the Atlantic Ocean influences were of special importance. Then annual and monthly quantiles were calculated to allow the classification of events according to rainfall totals. Rainfall homogeneous regions were established in SPS using climatology and quantiles. It was observed the constructive relationship between ENSO events and PDO phases, mainly on austral summer. PDO signals were noticed all over the SPS mostly on austral spring and summer. An additional analysis showed that Atlantic Multidecadal Oscillation (AMO) phases also contribute to SPS rainfall during austral summer and spring at the coast, only on summer at the country and during spring at the Mantiqueira Slopes. Apparently, there is no relation between ENSO events and AMO phases.