660 resultados para Poles


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The present work has as an objective to seize up some particular meanings of the Feast of Sant Ana (The saint which represents the city of Caicó/RN), a central event of the calendar festive-religious of that city, looking for to perceive on how it combines with the symbolic poles sacred: profane through the social bonds that are present there performed and expressed through the social networking and of local belongings. Such bond ties reveal themselves through a very especial manner, through the migration of returning to the feast, when collectively are produced and updated knowledge and codes that reinforce the representation of the local belonging, nominated as being caicoense . We seek on perceiving how the many events of this feast (from a perspective of a religious order as well as laic) acting on a conclusive way to an identity of the re-meaning of that city, especially in its relation with the migrant natives: the sons and daughters that return to the arms of Sant Ana

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Dissertação para obtenção do grau de Mestre em Arquitectura com Especialização em Gestão Urbanística, apresentada na Universidade de Lisboa - Faculdade de Arquitectura.

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Timber poles are commonly used for telecommunication and power distribution networks, wharves or jetties, piling or as a substructure of short span bridges. Most of the available techniques currently used for non-destructive testing (NDT) of timber structures are based on one-dimensional wave theory. If it is essential to detect small sized damage, it becomes necessary to consider guided wave (GW) propagation as the behaviour of different propagating modes cannot be represented by one-dimensional approximations. However, due to the orthotropic material properties of timber, the modelling of guided waves can be complex. No analytical solution can be found for plotting dispersion curves for orthotropic thick cylindrical waveguides even though very few literatures can be found on the theory of GW for anisotropic cylindrical waveguide. In addition, purely numerical approaches are available for solving these curves. In this paper, dispersion curves for orthotropic cylinders are computed using the scaled boundary finite element method (SBFEM) and compared with an isotropic material model to indicate the importance of considering timber as an anisotropic material. Moreover, some simplification is made on orthotropic behaviour of timber to make it transversely isotropic due to the fact that, analytical approaches for transversely isotropic cylinder are widely available in the literature. Also, the applicability of considering timber as a transversely isotropic material is discussed. As an orthotropic material, most material testing results of timber found in the literature include 9 elastic constants (three elastic moduli and six Poisson's ratios), hence it is essential to select the appropriate material properties for transversely isotropic material which includes only 5 elastic constants. Therefore, comparison between orthotropic and transversely isotropic material model is also presented in this article to reveal the effect of elastic moduli and Poisson's ratios on dispersion curves. Based on this study, some suggestions are proposed on selecting the parameters from an orthotropic model to transversely isotropic condition.

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Non-destructive testing has been used for many years to evaluate the in situ condition of timber piles. Longitudinal impact is usually applied on the top of piles to induce longitudinal wave to detect faults in piles due to the fact that the longitudinalwave has less dispersive nature at lowfrequency. On the other hand,when it comes to evaluation of poles in situ, it is different as poles are partly embedded in soil and it is more practical to produce bending waves, as the top of the pole is not easily accessible. However, bending wave is known for its highly dispersive nature; especially in the low frequency range which is usually induced in low strain integrity testing. As bending wave can be considered as a hybrid of longitudinal and shear waves, it will be helpful, if it could detect the component of these twowaves separately.To do so, components of displacements or accelerations along radial and longitudinal directions need to be determined. By applying Fast Fourier Transform (FFT) on the signals, the dominant frequencies can be obtained. It has been found that, the longitudinal component decreases along radial direction which indicates the presence of bending wave component and this finding allows to the application of ContinuousWavelet Transform (CWT) on the longitudinal component of wave signals in order to obtain phase velocity. Phase velocities at different frequencies are then determined to draw the dispersive curve and compare with analytical phase velocity curve. The dispersion curve matched well with the analytical curve. © 2013 Taylor & Francis Group.

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A class of non-stationary exact solutions of two-dimensional nonlinear Navier–Stokes (NS) equations within a thin rotating spherical shell were found as invariant and approximately invariant solutions. The model is used to describe a simple zonally averaged atmospheric circulation caused by the difference in temperature between the equator and the poles. Coriolis effects are generated by pseudoforces, which support the stable west-to-east flows providing the achievable meteorological flows. The model is superimposed by a stationary latitude dependent flow. Under the assumption of no friction, the perturbed model describes zonal west-to-east flows in the upper atmosphere between the Ferrel and Polar cells. In terms of nonlinear modeling for the NS equations, two small parameters are chosen for the viscosity and the rate of the earth’s rotation and exact solutions in terms of elementary functions are found using approximate symmetry analysis. It is shown that approximately invariant solutions are also valid in the absence of the flow perturbation to a zonally averaged mean flow.

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Low strain integrity testing is commonly used to assess the in situ condition of the poles or piles. For poles, it is important to calculate the embedment length and location of damage which is highly influenced by the accurate determination of the wave velocity. In general, depending on impact location and orientation, both longitudinal and bending waves may generate inside the pole, and these two waves have very distinct characteristics and wave velocity. These differences are even more prominent in the low frequency which is usually induced in the low strain non-destructive testing. Consequently, it will be useful if these two waves can be separated for the condition assessment of the poles. In this paper, a numerical analysis is performed on a pole considering that both waves are generated, and a method is proposed to differentiate these two waves based on an appropriate sensor arrangement that includes the location and the orientation of the sensors. Continuous wavelet transform is applied on the numerical signal to calculate the phase velocity of the waves and compared with analytical phase velocity curves. From the results, it can be seen that appropriate location and orientation of the sensors can separate the longitudinal and flexural waves as they match significantly well with the corresponding analytical phase velocity curves of these two waves.

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This paper presents an application of Wavelet Transfonn (WT) for determination of stress wave velocity for Non-destructive Testing of timber utility poles in service. For surface Non-destructive Testing (NDT), the hammer impact, which produces generally broadband frequency excitation, is used to generate stress wave. Moreover, due to practicality the impact location for field testing of a utility pole is on the side of the pole and 1.5 m above ground level. And the geometry of utility pole could not guarantee non-dispersive longitudinal wave. All of these issues have resulted in lack of accuracy and reliability of results from surface NDT in field testing. In recognition of such problem, this research explores methods to reliably calculate desired wave velocity by isolating wave mode and studying dispersive nature of utility pole. Fast Fourier Transfonn (FFT) is firstly conducted to determine the suitable frequency from a stress wave data. Then WT is applied on the wave data mentioned to perfonn time-frequency analysis. Velocity can be detennined by time history data of desired frequency from WT results which will be compared with the available analytical solution for longitudinal wave velocity. The results of the investigation showed that wavelet transfonn analysis can be a reliable signal processing tool for non-destructive testing in tenns of velocity detennination, which in tum also helps to detennine the embedded length of the timber pole.

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Timber is one of the most widely used structural material all over the world. Round timbers can be seen as a structural component in historical buildings, jetties, short span bridges and also as piles for foundation and poles for electrical and power distribution. To evaluate the current condition of these cylindrical type timber structures, guided wave has a great potential. However, the difficulties associated with the guided wave propagation in timber materials includes orthotropic behaviour of wood, moisture contents, temperature, grain direction, etc. In addition, the effect of fully or partially filled surrounding media, such as soil, water, etc. causes attenuation on the generated stress wave. In order to investigate the effects of these parameters on guided wave propagation, extensive numerical simulation is required to conduct parametric studies. Moreover, due to the presence of multi modes in guided wave propagation, dispersion curves are of great importance. Even though conventional finite element method (FEM) can determine dispersion curves along with wave propagation in time domain, it is highly computationally expensive. Furthermore, incorporating orthotropic behaviour and surrounding media to model a thick cylindrical wave (large diameter cylindrical structures) make conventional FEM inefficient for this purpose. In contrast, spectral finite element method (SFEM) is a semi analytical method to model the guided wave propagation which does not need fine meshes compared to the other methods, such as FEM or finite difference method (FDM). Also, even distribution of mass and stiffness of structures can be obtained with very few elements using SFEM. In this paper, the suitability of SFEM is investigated to model guided wave propagation through an orthotropic cylindrical waveguide with the presence of surrounding soil. Both the frequency domain analysis (dispersion curves) and time domain reconstruction for a multi-mode generated input signal are presented under different loading location. The dispersion curves obtained from SFEM are compared against analytical solution to verify its accuracy. Lastly, different numerical issues to solve for the dispersion curves and time domain results using SFEM are also discussed.

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Cette-recherche-action émerge d’une problématique élaborée à partir de l’observation des pratiques catéchétiques à la paroisse Saint-Joachim dans le diocèse de Montréal. L’essentiel du projet se situe en théologie pratique, menée dans le cadre de la praxéologie pastorale. Un premier chapitre situe l’historique de la catéchèse en paroisse. Le deuxième déploie l’observation de la pratique à partir des pôles structurels et des fonctions d’élaboration, mais aussi par la mise à contribution des parents qui ont accepté de répondre à un questionnaire. Le troisième pose la problématique de la mise à l’écart des parents dans l’éducation à la foi et est suivi d’une interprétation sur un changement de posture et un appel à la coéducation dans la foi tout en prenant compte des évolutions des familles à l’égard du religieux. Cela est fait à partir de référents théologiques principalement, enrichis de référents dans les domaines de l’éducation et des sciences sociales. Des pistes à envisager avec les parents et avec les catéchètes sont ensuite formulées, avec un accent mis sur la pratique du dialogue pastoral et la notion d’accompagnement, et également en faisant le lien avec les différentes dimensions de la vie chrétienne. Le dernier chapitre veut offrir une prospective dans la transmission de la foi en révélant le rôle missionnaire de la catéchèse qui s’accorde avec la nouvelle évangélisation et la pastorale des familles.

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Cette-recherche-action émerge d’une problématique élaborée à partir de l’observation des pratiques catéchétiques à la paroisse Saint-Joachim dans le diocèse de Montréal. L’essentiel du projet se situe en théologie pratique, menée dans le cadre de la praxéologie pastorale. Un premier chapitre situe l’historique de la catéchèse en paroisse. Le deuxième déploie l’observation de la pratique à partir des pôles structurels et des fonctions d’élaboration, mais aussi par la mise à contribution des parents qui ont accepté de répondre à un questionnaire. Le troisième pose la problématique de la mise à l’écart des parents dans l’éducation à la foi et est suivi d’une interprétation sur un changement de posture et un appel à la coéducation dans la foi tout en prenant compte des évolutions des familles à l’égard du religieux. Cela est fait à partir de référents théologiques principalement, enrichis de référents dans les domaines de l’éducation et des sciences sociales. Des pistes à envisager avec les parents et avec les catéchètes sont ensuite formulées, avec un accent mis sur la pratique du dialogue pastoral et la notion d’accompagnement, et également en faisant le lien avec les différentes dimensions de la vie chrétienne. Le dernier chapitre veut offrir une prospective dans la transmission de la foi en révélant le rôle missionnaire de la catéchèse qui s’accorde avec la nouvelle évangélisation et la pastorale des familles.

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In my eight years as a professional journalist, I have been a front line observer of the extreme level of violence which occurs everyday in our society. As victims, consumers or perpetrators of violence, this phenomenon is now a part of our existence. As a reporter for the Spanish national newspaper El País I have been witness to the most terrible acts of violence. In Venezuela, with one of the highest rates of criminality in the world, I saw piles of bodies stacked up in mortuaries. In Argentina, I reported on the most brutal crimes including the rape of children by policemen. I believe that my interest in the manifestations and causes of violence was aroused during my time as a journalist. On a personal level, I was deeply affected by the twin poles of attraction/repulsion which the violent images produced in me. The first time I visited New York in 2003, I talked to various people who were selling photos of the victims of the Twin Tower attacks. They had laid out their wares along the wire fence that separated Ground Zero from the main public areas. One particular photograph made an indelible impression on my mind: a ghost like corpse covered in white dust which was streaked with blood. It is an image I will never forget. If I remember well, a complete album of these gruesome images cost about ten dollars. At the same time, I also became interested in islamic terrorism: its complexity and the great impact it has made on Western society. One only has to look at the front page of the press around the world to read about war, terrorism or the constant violation of human rights. The words Al-Qaeda, Daesh, Boko Haram and Islamic State have sadly become parts of our everyday language. The nihilistic philosophy which promisess eternal life in exchange for self-inmolation is a new, highly worrying reality, especially painful when it involves young people who become indoctrinated through the social media. They have become the most loyal supporters of a fanatical and uncompromising version of Islam. The stark reality is that these young recruits to Jihad (holy war) were born in places like London, Paris, Rome or Madrid...

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Dissertação de Mestrado apresentada no ISPA – Instituto Universitário para obtenção de grau de Mestre na especialidade de Psicologia Clínica

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No funding agencies or grants indicated in the publication.

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This work intended to give a perspective of industrial wood protection in Portugal. A survey was made of the companies treating wood mainly for use classes 3 and 4 such as autoclave treatments with biocides and wood modification procedures. Currently there are 23 companies with 33 production plants with an autoclave installed for wood preservation by impregnation. There are also two companies producing modified wood by thermal treatment. Most of the plants are located in the central and northern regions of Portugal. The leading preservation chemicals used in Portugal are Tanalith E and Celcure brands. The main wood species used in all companies is Pinus pinaster from local producers. The products commercialized by the treating companies are diverse: pre-fabricated houses, garden furniture and playgrounds, decks, poles, stakes, and sawn wood. Modified wood producers sell mostly decks and cladding. Considerable changes are expected in the next few years due to the requirements of European Directives and the typical constraints of the Portuguese market.

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The recent values of heat flow data obtained for Greenland and West Antarctica are higher than it was supposed. In West Antarctica, values higher than 200mW/m2were found (Schroeder et al,2014) and in Greenland, values higher than 140 mW/m2 were detected in the Central part (Petrunin et al,2013). Thermal conductivity values of ice are relatively low at atmospheric pressure. This means that if we consider heat flowing by conduction, near the surface of the globe, with this heat flow values, the thermal gradients mill be elevated. A possible reason presented for the high heat flow values in Greenland is the existence of a thin lithosphere. The study of the ice melting near the poles is related with the changes in sea level. Obtaining this parameter is difficult. The time interval with measurement is not enough to obtain clear information about the past..The spatial distribution of heat flow shows clearly zones in the oceans with high values. How can this heat influence water movements in that regions and the temperature in the oceans?