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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

A field and laboratory study on the dynamic response of the Eddystone lighthouse to wave loading

Banfi, Davide January 2018 (has links)
Because little was known about how the masonry lighthouses constructed during the 19th century at exposed locations around the British Isles were responding to wave action, the dynamic response of the Eddystone lighthouse under wave impacts was investigated. Like other so called 'rock lighthouses', the Eddystone lighthouse was built on top of a steep reef at a site that is fully submerged at most states of the tide. Consequently, the structure is exposed to loading by unbroken, breaking and broken waves. When the breaking occurs, wave loading leads to complex phenomena that cannot be described theoretically due to the unknown mixture of air and water involved during the wave-structure interaction. In addition, breaking waves are generally distinguished from unbroken and broken wave due to the fact that they cause impulsive loads. As a consequence, the load effects on the structural response require a dynamic analysis. In this investigation the dynamic response of the Eddystone lighthouse is investigated both in the field and by means of a small-scale model mounted in a laboratory wave channel. In particular, field data obtained by the use of geophones, cameras and a wave buoy are presented together with wave loading information obtained during the laboratory tests under controlled conditions. More than 3000 structural events were recorded during the exceptional sequence of winter storms that hit the South-West of England in 2013/2014. The geophone signals, which provide the structural response in terms of velocity data, are differentiated and integrated in order to obtain accelerations and displacements respectively. Dynamic responses show different behaviours and higher structural frequencies, which are related to more impulsive loads, tend to exhibit a predominant sharp peak in velocity time histories. As a consequence, the structural responses have been classified into four types depending on differences of ratio peaks in the time histories and spectra. Field video images indicate that higher structural frequencies are usually associated with loads caused by plunging waves that break on or just in front of the structure. However, higher structural velocities and accelerations do not necessarily lead to the largest displacements of around a tenth of mm. Thus, while the impulsive nature of the structural response depends on the type of wave impact, the magnitude of the structural deflections is strongly affected by both elevation of the wave force on the structure and impact duration, as suggested by structural numerical simulations and laboratory tests respectively. The latter demonstrate how the limited water depth strongly affects the wave loading. In particular, only small plunging waves are able to break on or near the structure and larger waves that break further away can impose a greater overall impulse due to the longer duration of the load. As a consequence of the depth limited conditions, broken waves can generate significant deflections in the case of the Eddystone lighthouse. However, maximum accelerations of about 0.1g are related to larger plunging waves that are still able to hit the lighthouse with a plunging jet. When compared to the Iribarren number, the dimensionless irregular momentum flux proposed by Hughes is found to be a better indicator concerning the occurrence of the structural response types. This is explained by the fact that the Iribarren number does not to take into account the effects of the wide tidal range at the Eddystone reef, which has a strong influence on the location of the breaking point with respect to the lighthouse. Finally, maximum run up were not able to rise up to the top of the lighthouse model during the laboratory tests, despite this having been observed in the field. As a consequence, the particular configuration of the Eddystone reef and the wind could have a considerable bearing and exceptional values of the run up, greater than 40 m, cannot be excluded in the field.
42

Os faróis do saber e seus agentes de leitura em Curitiba – Paraná

Pereira, Paulla Rosane dos Santos Coelho 29 March 2016 (has links)
Submitted by Priscilla Araujo (priscilla@ibict.br) on 2017-06-19T17:12:57Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Paulla_Pereira.pdf: 1753502 bytes, checksum: fd110eb7bab38c19825058abd6655e44 (MD5) / Made available in DSpace on 2017-06-19T17:12:58Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Paulla_Pereira.pdf: 1753502 bytes, checksum: fd110eb7bab38c19825058abd6655e44 (MD5) Previous issue date: 2016-03-29 / Esta dissertação apresenta uma visão panorâmica dos Faróis do Saber da cidade de Curitiba – PR e do perfil dos agentes de leitura lotados em tais unidades. O objetivo é delinear um perfil da instituição e de seus colaboradores diretos, trazendo visibilidade a esta iniciativa bemsucedida na área de bibliotecas públicas e escolares, envolvendo a utilização de Tecnologias de Informação e Comunicação (TIC). As indagações gerais foram: o que são os Faróis do Saber? Como eles são administrados? Qual é o perfil dos agentes de leitura neles alocados, e como eles interagem com seu público? Para embasamento da pesquisa foram abordadas reflexões teóricas sobre bibliotecas públicas, bibliotecas escolares e a aplicação das TIC nesses ambientes. Também abordam-se teoricamente o conjunto de habilidades e as potencialidades reunidas sob a alcunha da competência em informação, no contexto escolar e para o profissional que lida com informação. Os métodos empregados para a obtenção de dados sobre os Faróis do Saber foram a análise dos documentos pertinentes levantados junto à Gerência de Bibliotecas e Faróis do Saber da Prefeitura Municipal de Curitiba, a entrevista junto ao gestor das unidades e o questionário online aplicado aos agentes de leitura que trabalham nos Faróis. O exame do material existente sobre os Faróis aponta que eles agem como bibliotecas públicas ou escolares, de acordo com a localização em que foi construído. Também acentua a importância do planejamento cultural como um todo, abrangendo diversas facetas de seu impacto na sociedade. Os resultados da entrevista com o gestor indicam que ele busca agregar a comunidade do entorno nas ações dos faróis, e que a gerência está empenhada na disponibilização não apenas de acervo e equipamentos digitais, mas de atividades especificamente elaboradas para cada grupo de usuários, aplicadas e acompanhadas pelos agentes de leitura. Os questionários aplicados aos agentes de leitura revelam que as rodas de leitura e a contação de histórias são as ações que se destacam como atividades regulares. Esses profissionais consideram que os aspectos relativos ao uso do computador, disponibilidade da internet e atualização do acervo deveriam ser desenvolvidos para garantir a sustentabilidade dos faróis. O perfil obtido dos agentes de leitura respondentes revela que este são formados geralmente em pedagogia; que a maioria possui alguma especialização no currículo, percebendo a importância da educação continuada em suas atividades e no desenvolvimento de competências em informação. Os agentes de leitura demonstram compreender a importância dos Faróis para a cidade, e do seu trabalho, no apoio à população e na construção da cidadania. Os dados levantados demonstram que há espaço para o desenvolvimento de ações envolvendo TIC e outras atividades culturais como a criação literária. / The objective of this dissertation is to provide a profile of the Faróis do Saber (Knowledge Lighthouses) of the city of Curitiba in Brazil and of their information professionals aiming at promoting greater visibility to this successful public initiative that involves public and school libraries. The research questions include, among others: what are their characteristics as information centers for public school students and for the community in general? What are the basic activities regularly promoted by the Faróis do Saber? How do they use information and communication technology (ICT) in these activities? What are the general characteristics of the information professionals (reading agents) working in these institutions, what is the profile of their information literacy, as well as their evaluation of the Faróis do Saber? As these institutions have a hybrid function as school and public libraries, we consider the literature that reflects about the functions of the public library as a social space and as a space for the promotion of reading abilities. The pedagogical functions of the school libraries, how ICT resources can be used in school and community libraries and what are the required information competences of information professionals in these contexts are also discussed. Empirical data were obtained from documents obtained from the Municipality, from an interview applied to the general manager of the Faróis do Saber and from a questionnaire applied to information professionals responsible for daily activities. The analysis of the interview indicate that the manager tries to involve the community in the activities promoted and that he is concerned with the effective use of the digital equipment provided, as well as with the promotion of activities planned for specific user groups. Data obtained from the reading agents reveal that the main regular activities are the promotion of reading. These professionals perceive the importance of the Faróis for the city and of their work for the community and in citizenship building. They also consider that computer and internet use and collection development should receive more attention to guarantee the sustainability of the institution. Pedagogy is the more frequent professional background and they usually have some specialization in their curricula. As a whole data obtained suggest that there is space for actions involving several cultural activities, as literary creation, with more intensive use of ICT.
43

L’archéologie sous-marine en Egypte. Rappel critique de son histoire et propositions pour une politique de gestion des vestiges immergés en Egypte, à la lumière des autres expériences en Méditerranée. / The underwater archeology in Egypt. Recall of its history and proposals for a management policy of the submerged vestiges in Egypt, in the light of other experiences in the Mediterranean.

El sayed, Mohamed 23 November 2012 (has links)
À côté de la jeune histoire de l’archéologie sous-marine égyptienne qui est retracée dans ce travail, les expériences similaires dans le monde méditerranéen sont beaucoup plus anciennes. Elles remontent au XVe siècle avec la découverte d’une épave du Ier siècle ap. J.-C. dans le lac Nemi, puis à la récupération d'une partie de la cargaison de l'épave antique d'Anticythère en 1901 grâce aux pêcheurs d'éponges grecs, ainsi qu’à la découverte en 1907 de l'épave romaine de Mahdia en Tunisie. Elles constituent des événements marquants dans le domaine de l'archéologie sous-marine. Mais l’archéologie sous-marine s’est développée de manière spectaculaire avec l’invention du scaphandre autonome par les français Jacques-Yves Cousteau et l’ingénieur Émile Gagnan. Cette invention provoqua une véritable révolution dans le domaine des activités sous-marines en 1942-1943. Ensuite les découvertes se succédèrent dans le bassin méditerranéen pendant plus d’un demi-siècle et de nombreux pays à travers le monde décidèrent de la mise en place de service archéologique spécialement dédié aux activités subaquatiques et sous-marines.Cette thèse porte sur une politique de gestion des vestiges immergés en Egypte, à la lumière des autres expériences en Méditerranée, afin d’attirer l'attention sur la richesse du patrimoine subaquatique égyptien à travers une étude dans le détail et dans son ensemble de l’action du Conseil suprême des Antiquités de l’Égypte et des diverses missions étrangères travaillant en Egypte. Elle propose une politique de protection efficace du patrimoine culturel subaquatique en Egypte, et des suggestions de développement du tourisme archéologique sous-marin et subaquatique, pour transformer ces richesses englouties en vecteur économique, tout en assurant leur protection adéquate par une législation spécifique qui n’existe pas encore en Egypte. / Beside this short history of underwater archeology in Egypt which is described in this work, similar experiences in the Mediterranean are much older, they go back to the fifteenth century with the discovery of a wreck from the first century AD, in Lake Nemi, later, the recovery of some objects from the ancient wreck of Anticythère in 1901 by the Greek fishermen of sponge, and the discovery in 1907 of the Roman wreck of Mahdia in Tunisia, are remarkable in the field of underwater archeology. But the underwater archeology has developed with the invention of the aqualung by the French Jacques-Yves Cousteau and the engineer Emile Gagnan. This invention caused a revolution in the field of underwater activities in 1942-1943. Then the underwater discoveries in the Mediterranean were succeeded and increased for more than a half century, and many countries around the world decided the establishment of an archaeological service specifically dedicated to underwater activities. This study focusses on management policy of underwater archaeology in Egypt, in the light of other experiences in the Mediterranean, in order to draw attention to the importance of the Egyptian underwater archaeology through a study in details of the activities of the Supreme council of Antiquities in Egypt and of the different foreign missions working in Egypt and to propose an effective protection policy of underwater cultural heritage in Egypt, also to develop the tourism of underwater archaeology, and to transform these vestiges in an economic vector, while ensuring an adequate protection by specific legislation that does not exist yet in Egypt.
44

De brignatium à gesoriacum : les amers, les navires et les ports en mare externum sous l'empire Romain / From Brigantium to Gesoriacum : the Landmarks, the Boats and the Harbours in Mare Externum under the Roman Empire

Delacroix, Barbara 08 December 2016 (has links)
La navigation sur l’arc atlantique à l’époque romaine est un sujet immense qui pâtit encore trop souvent de l’avis sceptique de chercheurs obnubilés par la Méditerranée. Il a donc fallu détricoter le mythe de l’océan infranchissable par l’étude approfondie des éléments interdépendants constitutifs de la navigation fluvio-maritime et moteurs de l’économie de l’arc atlantique, à savoir : l’amer, le navire et le port. Aussi l’étude de l’organisation du commerce atlantique sur les voies fluviales et maritimes, de La Corogne à Boulogne-sur-Mer, a-t-elle abouti à l’établissement d’une typologie « atlantique » tripartite. / Navigation in the Atlantic arc – enlarged to the English Channel and the North Sea – in Roman period, is a vast topic that, too often, still suffers from the sceptical opinion of researchers obsessed with the Mediterranean. It has been necessary to unravel the myth of the impassable Ocean, by means of a deep study of the mutually dependent elements forming the maritime and fluvial navigation and driving force of the Atlantic arc economy: the landmark, the vessel and the harbour. Moreover, the study of the organization of the Atlantic trade through the maritime and fluvial routes, from A Coruña to Boulogne-sur-Mer, have result in the establishment of a three-party ‘Atlantic’ typology.

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