La diffusion des techniques et du savoir-faire est un thème fort en matière d’hydraulique somptuaire. Les recherches menées sur la communauté des fontainiers français au service du roi d’Espagne Philippe V permettent d’approfondir cette problématique. Installés sur le domaine royal de La Granja de San Ildefonso dans la Sierra de Guadarrama près de Ségovie, les fontainiers mettent en œuvre les innovations techniques déjà appliquées sur le chantier de Versailles. Cette étude de cas ouvre la réflexion, d'une part, sur les transferts techniques et la circulation des savoirs entre France et Espagne à l'époque moderne, à une période où des liens étroits se sont tissés entre la cour madrilène et la cour versaillaise, et d'autre part, sur la place de l'Espagne comme centre d'innovation technologique.Les jardins et leurs fontaines deviennent objet de démonstration du pouvoir, expression de la domination politique et de la puissance royale. La symbolique de faste associée aux effets d'eau des fontaines de La Granja de San Ildefonso nécessite l'installation d'un nouveau réseau de techniciens spécialisés. Le roi d'Espagne fait alors appel à des fontainiers issus de Sceaux, Versailles, Trianon, Marly et Chantilly. Ces experts hydrauliciens participent pleinement au succès de l'opération, aux côtés des jardiniers, sculpteurs et architectes, prenant part à la conception des systèmes d’alimentation en eau des jardins et à l'entretien de ces infrastructures au quotidien.Tout au long du XVIIIe siècle, les innovations techniques mises en œuvre sur les jardins royaux français, transmises par l'intermédiaire de cette communauté de fontainiers expatriés, vont s'agréger à la tradition locale hydraulique espagnole, déjà le fruit de plusieurs transferts technologiques. Les jardins de San Ildefonso doivent être replacés dans une perspective à dimension européenne de diffusion des savoir-faire du personnel technique royal français. / The study about the community of French hydraulic engineers in Spain in the service of King Philip V is to question the history of technology focusing on royal palaces hydraulics and the circulation of knowledge. The arrival of the French hydraulic engineers in La Granja de San Ildefonso changed the hydraulic technologies in Spain. From this perspective, hydraulics is an expression of political domination. This case study allows to investigate technological innovations and their transfers between France and Spain during modern times, a period when the links between both the Madrid and the Versailles courts were very close.A new network of specialized technicians was necessary to give full dimension to the political domination which was perfectly conveyed by the fountains of La Granja de San Ildefonso with their highly symbolic and breath-taking water effects. That is why the King of Spain hired hydraulic engineers from Sceaux, Versailles, Trianon, Marly and Chantilly. It was thanks to these experts who designed water supply systems and daily routines to take care of the installations, by the side of gardeners, sculptors and architects, that the project ended up being a great success.During the whole 18th century, technical innovations were implemented in the French royal gardens, taught through this community of expatriated hydraulic engineers and enriched the local hydraulic Spanish tradition which was already the result of various technological transfers. The San Ildefonso gardens must be placed on a European perspective regarding the expertise of the French royal technical workforce.

In this work I have been looking at three small everyday sites that can tell big and unexpected stories of how we live together. These sites appear unremarkable at first glance, but on a second look are filled with contradictions and conflicts of interest. I speculate that these marginalised sites operate like “architectural footnotes” helping break the tempo, rhythm and tone of the city while expanding the scope of the narrative beyond the local and specific reading. I’m interested in how we can make sense of the city and critique it in a meaningful way when it appears so fragmented and seems impossible to define in single terms. I have been testing different approaches ranging from surveying, counting, measuring and mapping, to model making, interviews, drawing, film-making and texts. I have been interested in how these diverse methods can help me understand the city in different ways and what they do when used together.In part one: A Fence I investigate a trend towards the increasing enclosure of private courtyard/gardens and the severing of established pathways that are incredibly important for navigating the area. This led to questioning how ground-floor habitation, different forms of tenure, and regulation, affects public access and passage in the area.In part two: A Drinking Fountain I attempted to map the defunct drinking fountains in Stockholm and trace the origin of their (ubiquitous) design. Instead of finding fountains, however, I found a vacuum of responsibility, and questions were raised around why some infrastructures are more important than others and how shared/societal needs seem to have been increasingly privatised. In part three: Some Planting I looked at a recently built area of “urban-community-farming” in the middle of local park. Here tensions between the public, private and common are brought to the fore, questioning how attempts towards more local and participatory democratic processes affect rights of access to, and use of, public spaces, around flexibility and durability, and how we balance short term demands with long term visions.When seen together these “footnotes” can describe a trend towards withdrawal of the state and municipality through the dismantling of infrastructures, deregulation and outsourcing, resulting in an increasingly individualistic and privatised city. This is perhaps unsurprising in itself, but the work that comes out of these sites has helped reveal (to me at least) some of the surprising ways in which this has happened and continues to do so (albeit in different forms) and how this affects the ways in which we inhabit the everyday city.

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Ce manuscrit est centré sur la conception, l'amélioration et l'évaluation des protocoles des couches RESEAU, MAC et PHY. En particulier, nous nous focalisons sur la conception de nouveaux protocoles distribués pour une utilisation optimale/améliorée des ressources radio disponibles. Par ailleurs, nous caractérisons les performances des réseaux ad hoc à accès aléatoire au canal en utilisant des paramètres de plusieurs couches avec aptitude de transfert d'information (data forwarding). La majeure partie de nos analyses se base sur le concept d'interaction entre les couches OSI (cross-layer). En effet, cette nouvelle et attractive approche est devenue en peu de temps omniprésente dans le domaine de recherche et développement et dans le domaine industriel. Les métriques de performances qui nous intéressent sont la stabilité des files d'attentes de transfert, le débit, le délai et la consommation d'énergie. Principalement, la compréhension de l'interaction entre les couches MAC/PHY et routage du standard IEEE 802.11e DCF/EDCF, d'une part, et l'interaction entre noeuds en terme d'interférences, d'autre part, constituent le coeur central de notre travail / The present dissertation deals with the problem of under-utilization of collision channels and other related problems in wireless networks. It deals with the design of random access protocols for wireless systems and provides a mathematical framework for performance evaluation of multihop based heterogeneous wireless networks. This thesis is divided into three parts. In the first part, we propose new versions of slotted aloha incorporating power control, priority and hierarchy. Our simulations were important to understand the behaviour of such a system and the real impact of involved parameters (transmit power, transmit rate, arrival rate, hierarchy order). Both team problem (common objective function is maximized) and game problem (each user maximizes its own objective) were discussed. Introducing hierarchy seems to provide many promising improvement without/or with a low amount of external information. We also proposed two distributed algorithms to learn the desired throughput. Next, we developed in the second part an analytical Framework to evaluate performances of multihop based heterogeneous Wireless networks. We built a cross-layer model and derived expression of stability, end-to-end throughput and end-to-end delay. Furthermore, we provided an accurate approximation for the distribution of end-to-end delay in multihop ad hoc networks (operating with slotted aloha protocol). As a direct application, we highlighted how streaming and conversational flows could be supported in this class of ubiquitous networks. The third part of this thesis is devoted to understanding and modelling of IEEE 802.11e DCF/EDCF-operated multihop ad hoc networks. We indeed built a complete and simple APPLICATION/NETWORK/MAC/PHY cross-layered model with finite retries per packet per flow. We analyzed the stability of forwarding queues and derived expression of end-to-end throughput. We finally proposed a Fountain code-based MAC layer to improve the throughput/fairness over the network

Reliable and energy-efficient delivery of multimedia to mobile terminals in dynamic networks is a very challenging problem. In this thesis, we focus on a cooperative extension to the Digital Video Broadcasting – Handheld (DVB-H) standard, forming a cooperative broadcast network whereby terminal-to-terminal cooperation creates a distributed form of multi-input-multi-output (MIMO) that supplements existing fixed network infrastructure. First, we develop a novel and computationally-efficient hierarchical Markov model that is able to accurately perform a cross-layer packet error mapping between the physical and transport layers of the DVB-H/IPDC (IP DataCast) protocol stack. We then construct a discrete-event simulator in MATLAB® that incorporates all of the necessary modules to conduct dynamic multiterminal network simulations. Next, the convergence of cooperative wireless communication, Raptor application layer forward error correction (AL-FEC) and Network Coding (NC) is examined. Originally proposed for broadcasting over the Internet, the application of Raptor codes to wireless cooperative communications networks has been limited to date, but they have been mandated for use in DVB-H. Network coding is used to reduce energy consumption by opportunistically recombining and rebroadcasting required combinations of packets. Two novel coding-enabled cooperative relaying protocols are developed for multicast and multiple unicast file distribution scenarios that are transparent, fully distributed, and backwards compatible with today's systems. Our protocols are able to exploit several different forms of diversity inherent to modern wireless networks, including spatial diversity, radio interface diversity, and symbol diversity. Extensive simulations show that our protocols simultaneously achieve breakthroughs in network energy efficiency and reliability for different terminal classes and densities, allowing greatly improved user experiences. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2010-08-03 19:45:54.943

Wireless Sensor Networks (WSNs) that use tiny wireless devices capable of communicating, processing, and sensing promise to have applications in virtually all fields. Smart homes and smart cities are just few of the examples that WSNs can enable. Despite their potential, WSNs suffer from reliability and energy limitations. In this study, we address the problem of designing Distributed Data Storage Systems (DDSSs) for WSNs using decentralized erasure codes. A unique aspect of WSNs is that their data is inherently decentralized. This calls for a decentralized mechanism for encoding and decoding. We propose a distributed data storage framework to increase data survivability in WSNs. The framework utilizes Decentralized Erasure Codes for Data Survivability (DEC-DS) which allow for determining the amount of redundancy required in both hardware and data to allow sensed data to survive failures in the network. To address the energy limitations, we show two approaches to implement the proposed solution in an energy efficient manner. The two approaches employ Random Linear Network Coding (RLNC) to exploit coding opportunities in order to save energy and in turn prolong network life. A routing based scheme, called DEC Encode-and-Forward (DEC-EaF), applies to networks with routing capability, while the second, DEC Encode-and-Disseminate (DEC-EaD), uses a variation of random walk to build the target code in a decentralized fashion. We also introduce a new decentralized approach to implement Luby Transform (LT)-Codes based DDSSs. The scheme is called Decentralized Robust Soliton Storage (DRSS) and it operates in a decentralized fashion and requires no coordination between sensor nodes. The schemes are tested through extensive simulations to evaluate their performance. We also compare the proposed schemes to similar schemes in the literature. The comparison considers energy efficiency as well as coding related aspects. Using the proposed schemes can greatly improve the reliability of WSNs especially under harsh working conditions. / Thesis (Ph.D, Electrical & Computer Engineering) -- Queen's University, 2013-09-30 22:43:04.509

Thesis (MScEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: The discovery of sparse graph codes, used in forward error correction strate- gies, has had an unrivaled impact on Information theory over the past decade. A recent advancement in this field, called Fountain codes, have gained much attention due to its intelligent rate adaptivity, and lend itself to applications such as multicasting and broadcasting networks. These particular properties can be considered valuable in a wireless sensor network setting as it is capable of providing forward error correction, and the added conceptual network protocol related extensions. A wireless sensor network testbed in France, called SensLAB, provides an experimental facility for researchers to develop and evaluate sensor network protocols, aside from a simulation environment. Tremendous value can be added to the SensLAB community if an appropriate forward error correction design, such as Fountain codes, is deemed feasible for use on such a platform. This thesis investigates the use of Fountain codes, in a binary erasure channel environment, as a forward error correction strategy for the distribution of reliable data content over the SensLAB platform. A short message length LT code using two different decoding mechanisms were developed and evaluated for possible implementation. Furthermore, a short message length Raptor code was developed by using supplementary theory and optimisation techniques that permit scalability in terms of the message size. The results favoured the Raptor code design as it performs close to near optimal while still satisfying the rateless- and universality property, at low computational complexity. / AFRIKAANSE OPSOMMING: Die ontdekking van yl-grafiekkodes, van toepassing op foutkorreksie strategieë, het onlangs 'n ongeewenaarde impak op Informasieteorie gehad. In 'n onlangse vooruitgang in hierdie veld, genoem Fonteinkodes, word daar meer fokus geplaas op die intelligente tempo aanpassingsvermoë van hierdie kodes, wat nuttige toepassing kan inhou in multi-saai- en uitsaai netwerke. Hierdie eienskappe kan moontlik as waardevol beskou word in draadlose sensor netwerke weens die fout regstellingsvermoë en die bykomende konseptuele netwerk protokol verwante uitbreidings. 'n Draadlose sensor netwerk toetsplatvorm in Frankryk, genoem die SensLAB, bied navorsers die geleentheid om eksperimentele sensor netwerk protokolle te ontwikkel en te toets buite 'n tipiese simulasie-omgewing. Groot waarde kan bygevoeg word aan die SensLAB gemeenskap indien 'n geskikte foutkorreksie strategie ontwikkel word, soos Fonteinkodes, en as geskik beskou kan word vir hierdie platvorm. In hierdie tesis word Fonteinkodes saam met die SensLAB platvorm ondersoek, binne die raamwerk van 'n binêre verlieskanaal, om vir foutkorreksie oor die verspreiding van betroubare data in SensLAB op te tree. 'n Kort boodskap LT kode word voorgestel deur van twee verskillende dekoderings meganismes gebruik te maak. 'n Alternatief, genaamd Raptorkode, was ook ondersoek. 'n Raptorkode. 'n Kort boodskap Raptor kode, wat ontwikkel is met bykomende teorie en optimeringstegnieke, word ook voorgestel. Die bykomende tegnieke bied 'n skaleerbare boodskap lengte terwyl dit tempoloos en universeel bly, en lae kompleksiteit bied.

[pt] Para transmissão da informação de maneira confiável, em canais com apagamento, foram criados os códigos LT (Luby Transform), uma das principais classes de códigos fontanais. Estes códigos não têm uma taxa fixa, em outras palavras, eles têm taxa versátil. Esta dissertação aborda o estudo da transmissão de imagens através de canal ruidoso, AWGN (Aditive White Gaussian Noise), com o uso de Códigos LT. Investigou-se o desempenho usando uma modulação BPSK, dois esquemas foram testados: Um esquema para canal que inclui apagamento (BESC) e um outro que foi proposto usando um código Hamming em série com um código LT. O esquema LT-Hamming apresentou um ganho de código maior que o esquema BESC e o código convolucional de semelhantes características. Foi testado o esquema LT-Hamming para diferentes tipos de imagens em um canal AWGN usando a técnica SPIHT para a compressão das imagens. Para obter uma medida objetiva da qualidade da imagem recuperada foi usado o parâmetro PSNR (Peak Sinal to Noise Ratio) e foram apresentadas algumas imagens com o objetivo de analisar sua qualidade através de uma inspeção visual. Dado que o código LT é versátil para o que diz respeito à taxa de código, foi proposto um método para método para atribuir diferentes níveis de proteção da informação codificada, UEP (Unequal Error Protection). / [en] To transfer reliably information in erasure channels, LT (Luby Transform) codes were created, they are part of the main class of fountain codes, this codes don’t have fixed rate, in other words, they have a versatile code rate. This thesis address to the study of images transmission through noisy channel, AWGN (Aditive White Gaussian Noise) using LT codes. We investigated the performance using a BPSK modulation, two schemes were tested: A scheme of channel that includes deletion (BESC) and another that was proposed, using a Hamming code in series with a LT code. The LT-Hamming scheme present a gain code larger than BESC scheme and convolutional codes of similar characteristics. Was tested LT-Hamming scheme for different types of images on AWGN channel using the SPIHT technique for images compression. To obtain an objective measure of image quality was used the PSNR (Peak Signal Noise Ratio) and some images were presented in order to analize its quality through visual inspection given that LT code is a versatile for what concern the code rate it was proposed a method to assign different protection levels to the code information, UEP (Unequal Error Protection).

Submitted by JÚLIO HEBER SILVA (julioheber@yahoo.com.br) on 2016-11-22T18:56:50Z No. of bitstreams: 2 Dissertação - Isabel Adelorada Ciappina - 2016.pdf: 8586414 bytes, checksum: a6cf18895da4c8727267aa619d96a7f6 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Jaqueline Silva (jtas29@gmail.com) on 2016-11-30T15:45:46Z (GMT) No. of bitstreams: 2 Dissertação - Isabel Adelorada Ciappina - 2016.pdf: 8586414 bytes, checksum: a6cf18895da4c8727267aa619d96a7f6 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-11-30T15:45:46Z (GMT). No. of bitstreams: 2 Dissertação - Isabel Adelorada Ciappina - 2016.pdf: 8586414 bytes, checksum: a6cf18895da4c8727267aa619d96a7f6 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-10-28 / There are different debate about the history teaching that runs through decade the thread, inside them find debate as of Rusen (2007) in connection the teaching methodology and objective of teach history. The subject comes since the teacher‟s formation in the university, until your insertion in the class, with incorporation attempt the research made university in the pedagogic-didactic action for that no distances, serving as complementation form of theory with practice. The way that contributes very with approximation is the proposal by Bittencourt (2011) that mentions the utilization differents languages and source in the history teaching in the classroom, such as the use of literary fountain, for to bring the students of history contents. Therefore, a focus this research is in teach method through of using of literary fountain, in order to make it more attractive for students. Other teach focus is in the formation history thought of renaissance by humanists, contained in the proposed documents for analysis, in the workshops. The problems that move this research are: How to right the use literary fountain the history teaching? Because students are motivated to study history in high school? How to teach renaissance for high school students? Which this humanist thought in the “introduction” of the following works: Madness praise of Erasmo of Rotterdam, Utopia of Thomas More and The prince of Maquiavel? This study it embases in the notion of historic conscience of Rusen (2007), us estudy of didactic made for Bittencour (2011) and until didactic relations with practice teaching of Fonseca (2003). Besides, it supplement with the practice of workshops for to test the functionally of teaching method proposal the long of research. Arriving the conclusion that to approach literary fountain in the history teaching to turn the lessons more interesting keeping attention of students and proposing more participation them in the classroom, stimulating your reasoning and critical sense about of renaissance. / Existem diversos debates sobre o ensino de história, que perpassam décadas a fio, dentre eles encontram-se discussões como as de Rüsen (2007), em relação à metodologia de ensino e ao objetivo de se estudar história. Esses assuntos vêm desde a formação do professor, na universidade, até a sua inserção na sala de aula, com a tentativa de incorporar as pesquisas feitas na universidade nas ações didático-pedagógicas, para que não se distanciem, servindo como forma de complementação da teoria com a prática. Uma maneira que contribui muito com essa aproximação é a proposta por Bittencourt (2011), que menciona a utilização de diferentes linguagens e fontes no ensino de história em sala de aula, como o uso de fontes literárias, para aproximar os alunos dos conteúdos de história. Por isso, um dos focos desta pesquisa está no método de ensino através do uso de fontes literárias, no intuito de torná-lo mais atrativo para os alunos. Outro foco de estudo está na formação do pensamento histórico do Renascimento, pelos humanistas, contidas nos documentos propostos para a análise, nas oficinas. Os problemas que movem esta pesquisa são: Como adequar o uso de fontes literárias ao ensino de História? Porque os alunos se encontram desmotivados ao estudar História no Ensino Médio? Como ensinar o Renascimento para alunos do Ensino Médio? Qual o pensamento humanista presente na “introdução” das seguintes obras: Elogio da Loucura de Erasmo de Rotterdam, Utopia de Thomas More e O Príncipe de Maquiavel? Este estudo se embasa na noção de consciência histórica de Rüsen (2007), nos estudos de didática feitos por Bittencourt (2011) e ainda nas relações de didática com prática de ensino de Fonseca (2003). Além disto, se complementa com a prática de oficinas para testar a funcionalidade do método de ensino, proposto ao longo da pesquisa. Chega-se a conclusão que abordar fontes literárias, do Renascimento no ensino de história, torna as aulas mais interessantes e prendem mais a atenção dos alunos proporcionando maior participação destes, em sala de aula, estimulando seus raciocínios e senso crítico a respeito do Renascimento.

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