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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.
361

Le développement commercial de la Roumanie : entreprises françaises et intégration européenne / Comercial development of Romania : french companies and european integration

Nastase, Gianina Elena 19 March 2015 (has links)
La grande distribution en Roumanie est un phénomène récent qui justifie une étude. Ce phénomène est apparu dans les années 1992, après la chute du régime communiste en décembre 1989. Cet évènement a permis une libération des énergies dans tous les domaines, en particulier celui du commerce. La grande distribution s'est implantée à Bucarest et particulièrement à la périphérie pour ensuite s'orienter vers le centre-ville. La présence des axes de transport à l'entrée de la ville a facilité le groupement de plusieurs acteurs. En effet, le premier hypermarché s'est installé sur l'autoroute A1 près de Pitesti, au nord-ouest de Bucarest. Un deuxième groupement de sociétés s'est implanté à l'est de Bucarest, vers l'autoroute du Soleil qui relie la capitale au port Constanta. Le phénomène de la grande distribution s'est développé grâce à l'initiative des acteurs étrangers. Le manque des stratégies nationales explique que l'infrastructure et le transport sont insuffisants. Par son implantation périphérique, la grande distribution contribue à déplacer les limites de la ville. Cela montre à quel point l'activité commerciale détermine la périurbanisation et conditionne l'apparition de la zone métropolitaine bucarestoise / Hypermarket distribution is a rather recent phenomenon which justifies a study. It started in 1992 after the fall of the communist regime in December 1989. This event allowed a liberation of the energies in all the domains, in particular in the retail / trade. In the first time, large retailers took place in Bucharest and particularly in the suburbs. In a second time, it spread in the main town. The North of the capital is well enough served in highways. Thanks to the situation, a lot of commercial actors can settle in this place which becomes a trade area. We notice that the first hypermarket opened near the A1 highway towards Pitesti on the North West of Bucharest. A second group of companies goes to the East of Bucharest, next to the Sun highway which links the capital to the port Constanta. The phenomenon became more important thanks to foreign actors. The lack of national strategies explains that the utilities and transport's accessibility are insufficient. Because of its place around the town, hypermarket distribution moved the limits of the town. So we can observe that the trade is linked to suburbanization and marked the apparition of the metropolitan area of Bucarest
362

Storgatan 2.0 : A Concept to discuss redesign ideas for the main pedestrian street of Växjö

Vuori, Sanni January 2017 (has links)
Storgatan 2.0 is a study and design concept investigating the need for change of the main pedestrian street of the city of Växjö, in South Sweden. In order to propose a basis for discussions, and work as an inspiration for further renewal ideas, the design concept presents various, initial redesign visualisations of the site, Storgatan pedestrian street. The theoretical framework of this study leans on conducting urban studies with human-centred approach to city development. The exploratory research phase of the project was performed through several methods, including site observation, interview, and a survey for the local citizens. Also, relevant secondary research and necessary investigation of the context, Sweden, are part of the study. In the end, the project focuses on sorting and analysing the data, by using various visual thinking tools as a method. The outcome of the project is a proposal visualising the possibilities for Storgatan, based on the research results. The visualisations are not meant to provide detail-oriented final solutions, but defend the potential of Storgatan to become a stronger version of the main pedestrian street – an enjoyable, pedestrian-prioritised public place that is actively used and shaped by the citizens.
363

Etude de structures coplanaires à métamatériaux et à couche magnétique / Study of coplanar metamaterials structures with magnetic layer

Boukchiche, Faris 30 November 2010 (has links)
La croissance récente des télécommunications nécessite la conception de circuits miniaturisés fonctionnant au-delà du gigahertz. Les activités de recherche sont énormément consacrées à l’étude de circuits intégrés associés à des structures planaires. Les circuits planaires qui ont récemment subi d’importants développements technologiques, sont très attractifs pour leurs faibles coûts de réalisation, leur faible poids et dimensions. Les filtres connus en hyperfréquence peuvent être réalisés à partir de lignes imprimées planaires. Beaucoup de ces composants passifs ne présentent aucune agilité en fréquence. Le problème d’agilité en fréquence est résolu en utilisant des composants actifs ajustables ou des composants passifs dont on peut modifier les propriétés en appliquant un champ électrique (ferroélectrique) ou un champ magnétique (ferrite. . .). Le principal objectif de cette thèse est de proposer et de caractériser une ligne coplanaire main gauche aveclaquelle on peut obtenir un fonctionnement agile en fréquence et relativement de faibles pertes.C'est une étude sur de nouveaux matériaux "main gauche" ou métamatériaux réalisés à partir de lignes coplanaires sur substrat ferrite. L'utilisation de ces substrats permet une certaine agilité en fréquence. L’étude débute par la modélisation d’un segment de ligne non réciproque, puis l'étude de la structure complète (capacité — ligne non réciproque — inductance). La détermination des paramètres ABCD de la cellule élémentaire (L-C), permet de retrouver les paramètres S de cette cellule. On en déduira les constantes de propagation dans les deux sens et on vérifiera que la celluleest un matériau planaire « main gauche » non réciproque / The recent growth in telecommunications requires the design of miniaturized circuits operating beyond the gigahertz. Research activities are enormously dedicated to the study of integrated circuits associated with planar structures. Planar circuits, that have recently undergone major technological developments, are very attractive for their moderate cost of realization, low weight and dimensions. Filters known in microwave can be made from printed planar lines. Many of these passive components have no frequency agility. The problem of frequency agility is solved using adjustable active components or passive components which we can modify the properties by applying an electric field (ferroelectric) or a magnetic field (ferrite ...). The main objective of this thesis is to propose and characterize a coplanar line left hand with which we can obtain an agile frequency operation and relatively low losses. It is a study on new materials "left hand" or metamaterials made from coplanar lines on ferrite substrate. The use of these substrates allows some frequency agility. The study begins by modeling a non-reciprocal line segment, then study the complete structure (capacity - non- reciprocal line - inductance). The determination of the ABCD parameters of the unit cell (LC), allows us to find the S parameters of this cell. We will deduct the constants of propagation in both directions and we will verify that the cell is a non-reciprocal "left hand" planar material
364

Envoltórios circunstelares de estrelas jovens de massa intermediária / Circumstellar envelopes of intermediate mass young stars

Rodrigo Georgetti Vieira 20 September 2012 (has links)
As estrelas Herbig Ae/Be (HAeBe) representam os objetos de massa intermediária (2-10 Msol) na pré-sequência principal. Algumas de suas propriedades físicas são pouco compreendidas até o momento. Somente o estudo conjunto das informações fornecidas em diversos comprimentos de onda pode revelar as características do material circunstelar destes objetos. O objetivo deste trabalho de doutorado é analisar sob vários aspectos a estrutura, a composição e a evolução destes ambientes circunstelares. Para realização deste estudo, adotamos a amostra de candidatas a estrelas HAeBe detectadas pelo Pico dos Dias Survey (Vieira et al. 2003). Evitamos as possíveis contaminações desta amostra por estrelas em estágios mais avançados utilizando diagramas de cores, estimativas de extinção e características espectrais. A química da poeira circunstelar foi analisada a partir das propriedades dos espectros ISO disponíveis para nossos objetos. O perfil espectral do silicato em torno de 10 microns revelou características evolutivas do material circunstelar. O status evolutivo dos objetos mais embebidos foi determinado por meio de estimativas da massa de seus envoltórios circunstelares. Este estudo indicou que a maior parte desta sub-amostra se encontra no estágio intermediário entre a Classe 0 (Menv>>M*) e a Classe I (Menv<M*) de estrelas jovens. Detalhes da morfologia do disco de PDS340 foram analisados por imagens no infravermelho-médio, obtidas em bancos de dados. Estas observações impuseram vínculos à extensão e orientação espacial do disco nesta faixa espectral. As observações disponíveis em vários comprimentos de onda revelaram características da estrutura e evolução do material circunstelar associado a estrelas HAeBe. A perspectiva do desenvolvimento de um modelo completo que abranja todas estas informações é descrita na conclusão do trabalho. / Herbig Ae/Be (HAeBe) objects are intermediate mass (2 -10 Msun) stars in the pre-main sequence. Some of their properties remain not well understood to date. Only a full multi-wavelength study is able to reveal a reasonable scenario for their circumstellar material. The purpose of the present work is to study the structure, composition and evolution of these circumstellar environments. To address this issues, the sample of HAeBe candidates detected by the Pico dos Dias Survey (Vieira et al., 2003) was adopted. To avoid the contamination by more evolved stars, we developed an analysis based on two-color diagrams, extinction values and spectral features. The chemistry of the circumstellar dust was studied based on Infrared Space Observatory spectra available to our sample. The silicate feature around 10 micron revealed evolutionary information of the circumstellar material. The evolutionary stage of the more embedded sources was determined by estimates of their envelope masses. This study indicates almost all of this sub-sample to be in the intermediate phase between Class 0 (Menv>>Msun) and Class I (Menv<Msun). Mid-infrared images, retrieved from archive data, introduced morphological constraints to the orientation and extension of the disk associated to PDS340. The available observations for several wavelengths revealed some characteristics of the structure and evolution of the circumstellar material associated to HAeBe stars. The perspective of the development of a complete model, which encompasses all the available data, is described in the conclusion of this work.
365

White dwarf and subdwarf stars in the sloan digital sky survey / Estrelas anãs brancas e subanãs no sloan digital sky survey

Pelisoli, Ingrid Domingos January 2018 (has links)
Estrelas anãs brancas são o último estágio evolutivo observável de mais de 95% das estrelas e também um resultado comum na evolução de estrelas binárias. O estudo de anãs brancas é, portanto, uma ferramenta poderosa na compreensão da evolução de estrelas simples e binárias, da função de massa inicial local, e da perda de massa após a sequência principal, levando-nos a uma melhor compreensão do histórico de formação e evolução estelar de diferentes populações. Para que esses estudos sejam possíveis, é necessária uma amostra grande e preferencialmente completa de anãs brancas, cobrindo todo o intervalo de parâmetros físicos. A maneira mais simples de obter isso é utilizando dados de grandes projetos de mapeamento. O Sloan Digital Sky Survey já permitiu o aumento do número de anãs brancas conhecidas em cinco vezes até o data release 10. Neste trabalho, estendemos a busca por anãs brancas aos novos objetos no data release 12, descobrindo 3 157 novas anãs brancas e 1 349 novas subanãs. Pela primeira vez, estendemos essa busca para log g < 6.5, correspondente a M < 0.3 M⊙. Anãs brancas abaixo desse limite de massa não podem formar-se em um tempo de Hubble; contudo, se a estrela é parte de um sistema de binárias próximas, a perda de massa pode ser tão intensa que a anã branca resultante tem massa inferior ao limite por evolução simples. Esses objetos são chamados anãs brancas de massa extremamente-baixa (ELMs, do inglês extremely-low mass white dwarfs) Elas têm Teff < 20 000 K e 5.0 . log g . 6.5 e espectros muito similares a estrelas A de sequência principal. Menos de cem são conhecidas, e a maioria dos objetos foi descoberta tendo em conta um critério de seleção tendencioso, que excluiu ELMs frias (Teff < 9 000 K) e com mais baixa massa (M . 0.15 M⊙), tornando difícil verificar modelos e compreender as propriedades das ELMs como classe. Nós identificamos milhares de objetos cujas propriedades físicas, temperatura efetiva e log g, estão no intervalo de produtos de evolução binária, como as ELMs. Nós os chamamos de sdAs, referindo-nos ao seu log g que as coloca abaixo da sequência principal e seu espectro dominado por hidrogênio. As sdAs parecem conter populações estelares sobrepostas, e encontramos que 7% são mais compatíveis com (pre-)ELMs do que com objetos de sequência principal. Obtivemos espectroscopia resolvida temporalmente para 26 objetos e pudemos confirmar que 15 estão em binárias. Um objeto faz parte de um sistema eclipsante, enquanto outro é pulsante — o oitavo membro da classe de ELMs pulsantes. Outros seis objetos também apresentaram pulsações em nossas observações, cinco desses estão na vizinhança da faixa de instabilidade das ELMs. Com estes resultados, aumentamos a população de ELMs por um fator de 20%, elevando a fração de ELMs de 4 para 20%, um valor que é consistente com as previsões de modelos evolucionários. / White dwarf stars are the final observable evolutionary state of over 95% of stars and also a common outcome in binary evolution. Therefore, studying white dwarfs is a powerful tool to understand both single and binary stellar evolution, local initial mass function, and post-main sequence mass loss, leading us to a better comprehension of the history of stellar formation and evolution of different stellar populations. In order to make this type of studies possible, a large and preferably complete sample of white dwarf stars, covering the whole range of physical parameters, is required. The simplest way to achieve that is to take advantage of data provided by large surveys. The Sloan Digital Sky Survey has already allowed the increase of the number of known white dwarf stars fivefold up to its data release 10. In this work, we extended the search for white dwarfs to the new objects in the data release 12, discovering 3 157 new white dwarfs and 1 349 new subdwarfs. For the first time, we have extended this search to log g < 6.5, corresponding to M < 0.3 M⊙. White dwarfs below this mass limit cannot be formed through single evolution within a Hubble time; however, if the star is part of a close binary system, the mass loss of the system may be so intense that the resulting white dwarf has mass below the single evolution limit. These objects are known as extremely-low mass white dwarfs (ELMs) They show Teff < 20 000 K and 5.0 . log g . 6.5 and spectra very similar to main sequence A stars. Less than a hundred of them are known, and most objects were discovered relying on biased selection criteria, that excluded cool (Teff < 9 000 K), lowermass (M . 0.15 M⊙) ELMs, making it difficult to validate the models and comprehend the properties of the ELMs as a class. We have identified thousands of objects whose physical properties, effective temperature and surface gravity, place them in the range of by-products of binary interaction such as the ELMs. We have called them sdAs, referring to their sub-main sequence log g and hydrogen dominated spectra. They seem to be composed of overlapping stellar populations, and we found that at least 7% are more likely ELMs or their precursors, the pre-ELMs, than main sequence stars. Obtaining time-resolved spectroscopy for 26 objects, we could confirm 15 to be in close binaries. One of them is also an eclipsing system, while another is a pulsator — the eighth member of the pulsating ELM class. Other six new pulsators were found as part of our follow-up, five of them in the vicinity of the ELM instability strip. With these results, we increase the population of ELMs by 20%, raising the fraction of cool ELMs from 4 to 20%, which is consistent with the predictions from the evolutionary models.
366

Study of Long Span Bridge Design Based on Long Term Maintenance in Developing Countries / 途上国における長期維持管理を前提にした長大橋の設計法に関する研究

Matsumoto, Tsuyoshi 23 March 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22414号 / 工博第4675号 / 新制||工||1729(附属図書館) / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 杉浦 邦征, 教授 河野 広隆, 教授 八木 知己 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
367

Acute Coronary Syndrome With Unprotected Left Main Coronary Artery Culprit ― An Observation From the AOI-LMCA Registry ― / 左冠動脈主幹部を責任病変とした急性冠症候群 -AOI-LMCAレジストリ後向き観察研究-

Higami, Hirooki 24 September 2021 (has links)
京都大学 / 新制・論文博士 / 博士(医学) / 乙第13435号 / 論医博第2234号 / 新制||医||1054(附属図書館) / (主査)教授 石見 拓, 教授 佐藤 俊哉, 教授 湊谷 謙司 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM
368

Synthesis of SARS-CoV-2 Main Protease Inhibitors

Elfström, Mia January 2021 (has links)
Coronaviruses have been responsible for several global disease outbreaks over the last 20 years, including the “Severe Acute Respiratory Syndrome” in 2002/2003, the “Middle East Respiratory Syndrome” in 2012, and the “Coronavirus Disease of 2019 (COVID19)”. These viruses are highly contagious and can cause multiple medical disorders upon contraction, such as common cold or lower respiratory infections. SARS-CoV-2, the newly emerged coronavirus variant of 2019, has been confirmed as the cause of the ongoing COVID19 pandemic, which infected over 167 million people worldwide and, by the end of May 2021, has a death toll of over 3 million people. Even though several SARS-CoV-2 vaccines have made it to the market, no proven options have yet been discovered for treating COVID19 infections. The aim of this project is, therefore, to improve the potency of two active SARS-CoV-2 main protease (Mpro) inhibitors (ML188 and X77) by performing a structure-activity-relationship study where two specific sites of the inhibitors are altered. The inhibition activity of these compounds is then tested on isolated SARS-CoV-2 Mpro. The four-component Ugi reaction was utilized to synthesize the ML188 and X77 analogs, which were purified by column chromatography before testing. During this project, six pure analogs were successfully synthesized and will be sent shortly for testing. Inhibitors with good activity against SARS-CoV-2 Mpro will be further tested for their antiviral activity in cell-based infection assays. The results obtained from this study will later be used to perform a second structure-activity-relationship study to further improve the potency of the two inhibitors by developing a 2nd generation library.
369

Návrh úpravy letadla WT10 Advantic s pevným podvozkem dle předpisu CS-23 / Modification of the WT10 aircraft for the fixed landing gear according to the CS-23 requirements

Kubiena, Jaromír January 2017 (has links)
In this thesis, we deal with the design of a shock absorber variant for the type of main landing gear design of the aircraft WT10 Advantic. Then we focus on the design of the selected variant of the main landing gear. Next, we follow regulation CS-23 demands to calculate the load cases for the selected main lending gear. Then we design shock absorber based on the load during landing. We compile the equation of motion of the aircraft, which describes motion of the aircraft during landing, then we compute the equation. Finally, we focus on a stress analysis of the main landing gear and the shock absorber.
370

Zdravotně technické instalace a plynovod v penzionu pro seniory / Sanitary technical installations and pipeline in the pension for the elderly

Benková, Erika January 2020 (has links)
The master thesis is focused on the design of sanitary technical installations and pipeline in the pension for the elderly, in the cadastral area of Hodonín city. The pension is located in a plane terrain and is designed with four storeys, a partial basement and 3 aboveground floors. There are staff facilities, changing rooms, technical facilities, offices, gym, laundry, furniture storeroom, tool storeroom and maintenance room in underground floor. On the first floor there are kitchen, various storerooms, doctor, nursing facilities,meeting rooms and in the third part of the building are rooms for seniors. From the second to third floor there are rooms for seniors, doctor, nursing facilities, meeting rooms and dining rooms. The theoretical part deals with the issue of the occurrence of Legionell. The calculation and project part solves the sewerage, water supply and gas distribution in the given building.

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