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Azulejo na arquitetura brasileira: os painéis de Athos Bulcão / Wall tiles at the brazilian architecture: the panels of Athos BulcãoIngrid Moura Wanderley 31 August 2006 (has links)
Estuda a presença do azulejo na arquitetura brasileira desde uma perspectiva histórica e de seu processo produtivo, conferindo particular atenção à obra azulejar do artista plástico Athos Bulcão. O azulejo como material de revestimento percorre a arquitetura brasileira desde suas origens. Forte traço da herança construtiva portuguesa no Brasil, de uso corrente nas edificações coloniais, o azulejo é recuperado no começo do século XX no movimento de formação de uma arquitetura brasileira de caráter nacional, primeiro no neocolonial, e depois pelos modernos. A obra de Athos Bulcão parte dessa retomada e avança em elaborações formais geométrico-abstratas, que atualiza o sentido do azulejo como um protagonista da obra arquitetônica. / This research studies the presence of wall tile in brazilian architecture from a historical point of view and its productive process, granting special attention to Athos Bulcão wall tiles work. The use of wall tiles as a covering material goes back to the origins of brazilian architecture. Strong feature of portuguese architecture inheritance in Brazil, usual in colonial buildings, the use of wall tile recovered at the begin of 20th century with the creation of an authentic brazilian architecture with a strong national character, from the neo colonial style to the modern movement. Athos Bulcãos work begins with this restart and move forward to the development of geometric abstract forms, bringing wall tiles back as a protagonist in architecture.
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Regulation of aortic wall mechanics and stress : An experimental study in manÅstrand, Håkan January 2008 (has links)
The abdominal aorta (AA) in man is a vulnerable artery prone to atherosclerosis as well as aneurysmatic dilation. The underlying aortic composition, mechanical properties as well as the mechanisms responsible for age-related changes and vascular disease are however largely unknown. The aims of this study were 1) to characterize the age- and gender-related changes of the aortic wall components in vivo, using a mechanical model based on ultrasound measurements of pulsatile aortic diameter changes combined with intra-arterial pressure; 2) to validate ultrasound measurements of diameter and intima-media thickness (IMT) of the AA in order to calculate wall stress; 3) to study the stress driven remodeling response of the aortic wall in healthy individuals and the influence of age and gender; and 4) to study wall stress and remodeling of the AA in diabetic patients in order to elucidate the protective influence of diabetes on abdominal aortic aneurysm formation. The stiffness of the isotropic material (mainly elastin) increased in males despite the known decrease in elastin content with age. Further, an exponential increase in stiffness of the anisotropic material (mainly collagen) in males at high physiological pressure was found. This might be due to changed isoforms of collagen and increased glycation with age. Females were less affected than males. The reproducibility of the ultrasound measurements of diameter and IMT in the AA was acceptable (CV; 4% and 11% respectively), making it possible to calculate circumferential aortic wall stress in vivo. The age-related remodeling of the arterial wall led to increased diameter, and compensatory thickening of the wall preventing the circumferential wall stress from increasing in the common carotid artery of males and females, and the AA of females. However, the compensatory increase in wall thickness was defect in the male AA, where stress increased with age. Pulsatile stress influenced the material parameters of the AA, leading to increased stiffness of anisotropic material (mainly collagen), whereas stiffness of isotropic material (mainly elastin) was unaffected. Patients with diabetes mellitus had increased aortic wall thickness than controls, generating less circumferential stress. This coincides with the known reduction of abdominal aortic aneurysms in diabetic patients and may act as a protective factor.
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Elucidation of secondary cell wall secretion mechanisms of Arabidopsis thaliana, Poplar (Populus deltoides x P. trichocarpa) and Pine (Pinus contorta)Kaneda, Minako 05 1900 (has links)
Lignin is a key component of plant secondary cell walls, providing strength to the plant and allowing water transport. Lignin is a polymer of monolignols that are synthesized in the cell and transported into the cellulose rich cell wall. The primary goal of this thesis is to understand the mechanism(s) of monolignol deposition during xylogenesis. The currently accepted theory is that monolignols are exported by Golgi-mediated vesicle delivery to the secondary cell wall. When this theory was re-examined using cryofixed developing pine, quantitative autoradiography showed that monolignols did not accumulate in Golgi but were rapidly translocated from cytosol to cell wall. This suggests alternative mechanisms, such as membrane transporters, work in monolignol export. ATP binding cassette (ABC) transporters were chosen because they transport other secondary metabolites and some ABC transporter encoding genes are highly expressed in lignifying cells. Four candidate ABC transporters were selected in Arabidopsis (ABCB11, ABCB14, ABCB15 from the ABCB/MDR subfamily and ABCG33 from the ABCG/PDR subfamily) and shown to have overlapping, high vasculature expression patterns. Mutants with T-DNA insertions in single ABC transporter genes had no change in lignification of inflorescence stems. However, a reduced polar auxin transport phenotype was detected in mutants of ABCB11, ABCB14 and ABCB15. An additional approach was the use of inhibitors of ABC transporters. A new assay, which was developed to quantify lignification in primary xylem of Arabidopsis roots, demonstrated that ABC inhibitors did not change lignin deposition.
Monolignols are exported and polymerized in the polysaccharide matrix of the cell wall, which includes hemicelluloses that may organize monolignols during polymerization. Since diverse lignified cell types are enriched in either G- or S-lignin, I hypothesized that this pattern could reflect different hemicellulose distributions, which was examined using antibody labeling of xylans or mannans in hybrid poplar xylem. While xylans were generally distributed in all secondary cell walls, mannans were enriched in fibers but not in the ray and vessel walls. In summary, during secondary cell wall deposition, monolignols are exported by unknown transporter(s) rather than Golgi vesicles. In developing poplar wood, the monolignols are deposited into diverse hemicellulose domains in different cell types. / Science, Faculty of / Botany, Department of / Graduate
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In Vitro Investigation of Cell-Free Layer Formation in Microchannels: Dependency on the Red Blood Cell Aggregation and Field of ShearGliah, Omemah Rajab January 2018 (has links)
Red blood cells (RBCs) form approximately 40 to 45% of the human blood volume, and their behaviour and characteristics are the main determinant of blood properties, such as viscosity. RBCs are deformable species and stack together under low shear rate to form aggregates or rouleaux. Flowing RBCs migrate away from the wall leaving a cell-depleted layer known as the cell-free layer (CFL). This layer contributes to the blood viscosity and exchange between the RBCs and the target cells: a thinner CFL enhances the exchange process by reducing the diffusion distance. The formation of this CFL, however, is not yet completely understood.
The goal of this study is to improve the understanding of the formation of the CFL in the micro-flow. This was accomplished by studying the effects of changing both the flow rate and the microchannel geometry on blood flow in microchannels.
In this work, 10% hematocrit human blood suspensions were prepared in native plasma and flowed through poly-dimethylsiloxane (PDMS) microchannels of 100 μm x 34 μm cross-section. Investigation of the flowing cells was performed by using micro particle image velocimetry (μPIV) coupled with a high-speed camera. First, the high-speed camera images were processed with customized Matlab programs to detect and measure the CFL thickness and the RBC aggregates sizes. Second, the blood flow velocity profiles were measured using μPIV in order to determine the actual flow rate, the RBCs’ centerline velocity, and the shear rate.
The results showed that the increase in both flow rate and shear rate significantly reduced the CFL thickness and RBC aggregates size. Comparison of the upstream and downstream measurements in the bifurcating microchannel showed that the change in microchannel geometry did not significantly influence CFL thickness and RBC aggregate size, while within the daughter branches, RBCs tended to flow close to the inner wall resulting in an undetectable CFL at the inner wall and in a larger CFL at the outer wall of the branch. These in vitro results quantitatively relate CFL thickness and RBC aggregate size at different shear rates. The findings are of immediate interest regarding the understanding of microcirculation and improved designs of microchips.
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Reinforced Concrete Shear Walls with Welded Wire Grids as Boundary Element Transverse ReinforcementNavidpour, Mansour 15 May 2018 (has links)
Reinforced concrete shear walls as seismic force resisting systems may experience inelastic deformations if subjected to strong seismic excitations. These walls are designed to provide strength, stiffness, energy dissipation capacity and lateral drift control for seismic resistance. Shear wall deformability is largely dependent on adequate confinement of core concrete in boundary elements, prevention of longitudinal bar buckling, as well as proper design and detailing of the web section.
Conventional transverse reinforcement placed in shear wall boundary elements consists of hoops, overlapping hoops and crossties, based on the geometry and number of longitudinal bars used. The confinement steel requirement of current building codes (ACI 318 or CSA A23.3) often results in congestion of steel cage due to the high transverse reinforcement ratio required. Placing multiple hoops with 135-degree bends combined with crossties to satisfy the code confinement requirements can create concrete placement and construction problems. In addition, the required time to assemble conventional steel cages with multiple individual ties per spacing can be time consuming, potentially impacting the overall cost and duration of construction.
Welded Wire Reinforcement (WWR) is available in the construction industry as concrete reinforcement in the form of welded wire fabric (WWF) manufactured from relatively small diameter wires in comparison to the bar sizes typically used in structural applications. As an alternative to using conventional transverse hoops, prefabricated WWR grids can be used to provide required transverse reinforcement in boundary elements. WWR grids are manufactured using robots to weld cut steel pieces accurately before they are shipped to the job site, resulting in better construction quality and reduced construction time. However, research on the use of WWR is limited in the literature. Further experimental and analytical research is needed to establish design requirements for such reinforcement, especially when used in earthquake resistant construction with requirements for ductile response.
The current research project, involved three main phases; i) tests of 3 large-scale reinforced concrete shear walls with WWR grids used as boundary element transverse reinforcement, ii) material tests of grid samples, including those cast in concrete, iii) non-linear finite element analysis. The wall tests were conducted under slowly-applied lateral deformation reversals to investigate their strength and ductility for suitability as seismic resistant structural elements. Material tests were conducted to have a better understanding of WWR behavior, especially their weld capacity. Analytical research was undertaken to expand the experimental findings on shear wall behavior, as well as to conduct parametric investigation to understand the impact of changes in grid strength and ductility.
The results indicated that WWR grids can be used as boundary element transverse reinforcement in earthquake resistant shear wall. However, strength and ductility of grids should be established carefully prior to such application. Design strength of WWR grids should be established through burst tests to ensure ductile yielding of wire reinforcement prior to premature weld failure. Those grids that exhibit weld failures may be used with reduced design strength to permit the development of sufficient inelastic deformability in flexure-dominant shear walls.
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Vélocimétrie par Image de Particules Holographique pour les Mesures de Turbulence de Paroi / Holographic Particle Image Velocimetry for Wall Turbulence MeasurementsKuhlmann Abrantes, Juliana 30 March 2012 (has links)
La compréhension de la dynamique de la turbulence de paroi a déjà fait l'objet de nombreuses études expérimentales et numériques depuis des décennies. Le principal intérêt pratique de ces études tient au fait que la contrainte de cisaillement pariétale (et donc le frottement) est étroitement liée à la dynamique des structures à la proximité de la paroi. Les techniques expérimentales en mécanique des fluides ont également fait de grands progrès ces dernières années. Ce travail présente le développement d'une méthode expérimentale visant à fournir des mesures 3D-3C de l´écoulement dans la région de très proche paroi, en vue de mesurer la contrainte de cisaillement à la paroi avec une précision améliorée. Dans ce but, une technique originale de Vélocimétrie Holographique par Images de Particules a été mise au point. Les mesures sont effectuées dans un petit volume à proximité de la paroi dans la soufflerie au Laboratoire de Mécanique de Lille. Des mesures détaillées dans un de l’ordre de 1.5mm3 sont rendues possibles grâce l'utilisation d'un objectif de microscope pour l'agrandissement du champ objet. Les particules sont éclairées par le côté, la lumière diffusée a 90o se recombine avec l'onde de référence pour un enregistrement holographique en ligne de type Gabor. Une procédure d'étalonnage a été développée afin de relier l'espace de reconstruction de l’image holographique aux coordonnées dans le volume de mesure. L'analyse des résultats montre que les images de particules sont reconstruites avec une très bonne résolution axiale, ce qui conduit à penser que la configuration est bien adapté à cette type de mesure. Ces résultats montrent également qu’une optimisation et des ajustements sont nécessaires pour d'améliorer les résultats de suivi de particules / Continuously improving the understanding of wall turbulence dynamics has been the goal of many experimental and numerical studies for decades. The main practical aspect that makes this knowledge so crucial is the fact that the wall shear stress is closely related to the dynamics of the near-wall structures. Experimental techniques in fluid mechanics have also experienced a great amount of advances in recent years. The present work details the development of an experimental configuration aimed at providing 3D-3C flow measurements in the very near-wall region of a large wind tunnel facility, leading to the assessment of the wall shear stress with improved accuracy. With that goal, a technique known as Holographic Particle Image Velocimetry is used, and measurements are made in small volumes close to the wall in the wind tunnel at Laboratoire de Mécanique de Lille. Full measurements in volumes as small as 1.5mm3 are made possible with the use of a microscope objective for magnification of the object field. Particles are illuminated from the side and the 90o scattered field recombines with reference wave for holographic inline recording. A calibration procedure is performed in order to relate reconstruction space coordinates to real measurement volume coordinates. Analysis of resulting particle fields shows that particle images reconstruct with very good axial accuracy, leading to believe that the configuration is indeed suited for this type of measurement. However, some optimization and adjustments are needed in order to improve the particle tracking results
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AMBIÊNCIAS NA PAREDE: CONCEPÇÕES ESPACIAIS EM PINTURA E DESENHO / AMBIENCES ON THE WALL SPATIAL CONCEPTIONS IN PAINTING AND DRAWINGNunes, Michele Martins 26 April 2010 (has links)
This master degree dissertation consider the individual plastic production entitled Ambiences on the Wall, composed of eight works that were produced during
the masters course. The plastic proposal starts in perceptions of a particular universe (home-intimacy), seeking its re-development through the creative process, bringing to the same level the relations between painting and drawing, color and achromatic, perennial and ephemeral, memory and present, real and fantastic. In these works, the house's rooms are represented by painting with nuances of gray and by black lines installed on white walls. Opposed to these scenarios are superimposed colored
pictures, composed of appropriated elements of cubism. The visual poetic investigation starts on the establishment of these works, focusing on different conceptions of space that they suggest: the represented spaces, the relationship with the common space and the perceptions of the house s environments. First is presented the proposal, which seeks to combine oil painting on canvas and drawing
on the wall with adhesive. The text deals with the representational systems that are chosen for such combination, and with the counterpoint chromatic x achromatic that the works present. Later, aspects of the works are considered, and also its relationship with the space around it. Finally, the text discusses the thematic issues related to the represented spaces and the figures that inhabit them. / Esta dissertação busca estabelecer uma reflexão referente à produção plástica individual intitulada: Ambiências na Parede, composta por oito trabalhos que foram produzidos durante o curso de mestrado. A proposta plástica parte de
percepções de um universo particular (casa-intimidade), buscando sua reelaboração através do processo criativo, trazendo ao mesmo plano as relações entre pintura e desenho, cor e acromático, perene e efêmero, memória e presente, real e fantástico. Nestas obras, os cômodos da casa são representados através da pintura em nuances de cinza e por linhas pretas instaladas sobre paredes brancas.
Contrapondo-se a estes cenários, são sobrepostas figuras coloridas, compostas por elementos apropriados do cubismo. A investigação poética visual se dá a partir da instauração destes trabalhos, centrando-se nas diferentes concepções espaciais que estas obras sugerem: os espaços representados, a relação com o espaço comum e
a percepção dos ambientes da casa. Primeiramente é apresentada a proposta, que busca combinar pintura a óleo sobre tela e desenho com adesivo sobre a parede.
São abordados os sistemas representacionais escolhidos para tal combinação, bem como o contraponto entre cromático x acromático que as obras apresentam. Posteriormente são refletidos aspectos referentes à obra e sua relação com o
espaço que a circunda. E por fim o texto discorre sobre as motivações temáticas referentes aos espaços representados e as figuras que neles habitam.
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Identité et mémoire : art contemporain en RDA et dans les nouveaux Länder à partir de 1971 : Lutz Dammbeck, Karla Sachse / Identity and Memory : Contemporary art in the GDR and in the new Länder from 1971 : Lutz Dammbeck, Karla SachseSchwabe, Stefanie 30 November 2012 (has links)
Cette thèse propose un regard transitif sur l'art contemporain en RDA des années 1970 et 1980 et dans les nouveaux Länder en s'appuyant sur l'exemple de deux artistes, Lutz Dammbeck et Karla Sachse. Leurs productions artistiques réalisées avant et après la chute du mur de Berlin, reflètent le processus de construction identitaire en RDA et questionnent également la construction de la mémoire collective allemande. Le premier chapitre propose un aperçu des éléments d'histoire qui ont contribué à cette construction identitaire est-allemande qui touchait toute la société. Les artistes présenté-e-s dans le deuxième et troisième chapitre de cette thèse sont exemplaires pour un grand nombre d'artistes pouravoir refusé la doctrine du réalisme socialiste et n’avoir pas attendu la fin de la RDA pour créer des oeuvres pertinentes et subversives. Les années 1989 et 1990, l'année de la chute du mur et l'année de la réunification allemande, représentent bien un tournant géo-politique important, mais ne signifient pas réellement une rupture pour les artistes issu-e-s des scènes alternatives est-allemandes, comme c’est le cas pour Lutz Dammbeck et Karla Sachse / This thesis proposes a transitive view on contemporary art in the GDR in the 1970s and 1980s and in the new Länder based on the example of two artists, and Lutz Dammbeck and Karla Sachse. Their artistic productions performed before and after the fall of the Berlin Wall, reflect the process of identity construction in the GDR and also question the construction of Germany's collective memory. The first chapter provides an overview of the history that contributed to the construction of identity affecting the whole German society. The artists presented in the second and third chapter of this thesis are exemplary for many artists who refused the doctrine of socialist realism and did not wait for the end of the GDR tocreate important and subversive works. The years 1989 and 1990, the year the Berlin Wall fell and the year of German reunification, represent an important geo-political turn, but mean not really an aesthetic rupture for artists from east German alternative scenes as it is the case for Lutz Dammbeck and Karla Sachse
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Dinâmica de paredes de domínios em microfios amorfos recobertos por vidroBeck, Fábio 18 January 2010 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Amorphous glass-coated microwires are materials with soft magnetic properties suitable for various technological applications, mainly magnetic sensors. One of the outstanding properties of microwires with positive magnetostriction is the magnetic bi-stability, that means, the inversion of the magnetization is done by one magnetic domain wall displacement along the wire. In this work it was developed a system to determine the domain wall speed in microwires and studied its dynamic. Particularly, were studied the relation between domain wall speed, magnetic field and magnetoelastic anisotropy in Fe77;5Si7;5B15 microwires. It has been verified that the main source of domain wall damping is the eddy-currents and spin relaxation, both with a strong relation with the magnetoelastic energy. The magnetoelastic energy is changed by the axial applied stress which, by its time, modifies the damping mechanisms. It was also verified
that the domain wall damping present different behavior at low (mainly eddy-currents) and high applied stress (spin relaxation). / Microfios amorfos recobertos por vidro são materiais com propriedades magnéticas macias adequadas para várias aplicações tecnológicas, especialmente sensores magnéticos. Uma das propriedades interessantes dos microfios com magnetostricção positiva é a biestabilidade magnética,
cuja inversão da magnetização se dá pela propagação de uma parede de domínio ao longo do material. Nesse trabalho foi desenvolvido um sistema para a determinação da velocidade de uma parede de domínio em microfios e estudada a dinâmica dessa parede. Em particular, foram estudadas as relações entre velocidade da parede de domínio, campo magnético e anisotropia magnetoelástica em microfios amorfos com composição nominal de Fe77;5Si7;5B15. Verificouse
que os principais mecanismos de amortecimento das paredes de domínio têm origem nas microcorrentes de Foucault (eddy-currents) e na relaxação de spins, ambas com forte dependência da energia magnetoelástica. A energia magnetoelástica varia com a aplicação de uma tensão axial ao fio influenciando os mecanismos de amortecimento. Verificou-se também que a variação do amortecimento efetivo das paredes de domínio com a tensão tem comportamentos
distintos a baixas (eddy-currents) e altas tensões aplicadas (relaxação de spin).
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Development of Steel Slit Wall Dampers with Embedded Condition Assessment Capabilities / 損傷検知機能を内蔵した鋼製スリット壁ダンパーの開発Jacobsen, Andrés Pohlenz 24 November 2010 (has links)
Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第15723号 / 工博第3337号 / 新制||工||1504(附属図書館) / 28268 / 京都大学大学院工学研究科建築学専攻 / (主査)教授 中島 正愛, 教授 吹田 啓一郎, 教授 金子 佳生 / 学位規則第4条第1項該当
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