972 resultados para Still life
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When a structure vibrates immersed in a fluid it is known that the dynamic properties of the system are modified. The surrounding fluid will, in general, contribute to the inertia, the rigidity and the damping coefficient of the coupled fluid-structure system. For light structures, like spacecraft antennas, even when the fluid is air the contribution to the dynamic properties can be important. For not so light structures the ratio of the equivalent fluid/structure mass and rigidity can be very small and the fluid contribution could be neglected. For the ratio of equivalent fluid/structure damping both terms are of the same order and therefore the fluid contribution must be studied. The working life of the spacecraft structure would be on space and so without any surrounding fluid. The response of a spacecraft structure on its operational life would be attenuated by the structural damping alone but when the structure is dynamically tested on the earth the dynamic modal test is performed with the fluid surrounding it. The results thus are contaminated by the effects of the fluid. If the damping added by the fluid is of the same order as the structural damping the response of the structure in space can be quite different to the response predicted on earth. It is therefore desirable to have a method able to determine the amount of damping induced by the fluid and that should be subtracted of the total damping measured on the modal vibration test. In this work, a method for the determination of the effect of the surrounding fluid on the dynamic characteristics of a circular plate has been developed. The plate is assumed to vibrate harmonically with the vacuum modes and the generalized forces matrix due to the fluid is thus computed. For a compressible fluid this matrix is formed by complex numbers including terms of inertia, rigidity and damping. The matrix due to the fluid loading is determined by a boundary element method (BEM). The BEM used is of circular rings on the plate surface so the number of elements to obtain an accurate result is very low. The natural frequencies of the system are computed by an iteration procedure one by one and also the damping fluid contribution. Comparisons of the present method with various experimental data and other theories show the efficiency and accuracy of the method for any support condition of the plate.
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Abstract While Europe is slowly recovering from the economic recession, its effects on labour markets are still visible. The number of jobless families has increased and previous research has shown that unemployment can affect the wellbeing of both parents and their children. In this study we explored the links between parental unemployment and youth life satisfaction by considering the potential moderating roles played by satisfaction with family life and perceived family wealth. We used descriptive statistics, correlations, simple moderation and moderated moderation models of regression on data from a representative sample of 3937 Portuguese students (Mage = 13.9 years; SD ± 1.7; 48 % boys). Results showed that the negative effects of parental unemployment on youth life satisfaction were moderated by youth perceived satisfaction with family life but not by perceived wealth. This suggested that during family unemployment, young people satisfied with their family life are less vulnerable to the negative effects of parental unemployment on their life satisfaction. The relationship between parental unemployment and youth well-being requires further research, especially during periods of labour market crisis.
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It is a fact that the uncertainty about a firm’s future has to be measured and incorporated into a company’s valuation throughout the explicit analysis period – in the continuing or terminal value within valuation models. One of the concerns that can influence the continuing value of enterprises, which is not explicitly considered in traditional valuation models, is a firm’s average life expectancy. Although the literature has studied the life cycle of a firm, there is still a considerable lack of references on this topic. If we ignore the period during which a company has the ability to produce future cash flows, the valuations can fall into irreversible errors, leading to results markedly different from market values. This paper aims to provide a contribution in this area. Its main objective is to construct a mortality table for non-listed Portuguese enterprises, showing that the use of a terminal value through a mathematical expression of perpetuity of free cash flows is not adequate. We provide the use of an appropriate coefficient to perceive the number of years in which the company will continue to operate until its theoretical extinction. If well addressed regarding valuation models, this issue can be used to reduce or even to eliminate one of the main problems that cause distortions in contemporary enterprise valuation models: the premise of an enterprise’s unlimited existence in time. Besides studying the companies involved in it, from their existence to their demise, our study intends to push knowledge forward by providing a consistent life and mortality expectancy table for each age of the company, presenting models with an explicitly and different survival rate for each year. Moreover, we show that, after reaching a certain age, firms can reinvent their business, acquiring maturity and consequently postponing their mortality through an additional life period.
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This paper aims to reflect on the teaching of Portuguese language in the context of twenty-first century, taking as its starting point the proposal of multiliteracies. We propose to discuss the applicability of genres in the classroom as a condition to ensure the construction of fundamental knowledge to social practices of language. For this, we rely on recent studies on the possibilities that the genre can bring to practice reading, writing papers, and linguistic analysis. We intend, therefore, to assist the planning of teachers who still find themselves unsure on curricula that suggest what they have to do, but did not say how. Understand the reason why this work is another contribution to the teaching of Portuguese in the final years of elementary school and high school bringing out a space for discussion about what needs to be taught and some teaching procedures that favor the democratization of school and interaction linguistics. Curricular innovations and new ways of thinking about teaching and learning of mother tongue are already part of the reflections of most professionals, but there is still an open field to think of more effective alternatives through multimodality an interactionist conception of language.
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The present work proposes a reading of the artistic-intellectual project of the Portuguese writer Augusto Abelaira, from de novels The City of Flowers and Bolor, in order to place him in the scenery of the Portuguese neo-realism and the intellectual resistance against fascism. The expression of the idealizations and disappointments in the work of Abelaira points to an opposite direction to that identified with the socialist realism and with what was conventionally called doctrinaire neo-realism in Portugal before the public emergency of the controversy between those who defended the primacy of the content and another aesthetic response that problematizes the pre-eminence of a specular model. Thus, there never was an internal homogeneity neither aesthetic nor theoretical in the movement. The public emergency of this debate translates a controversy that is not confined to the aesthetic, but is, in its most profound dimension, theoretical and political. The objective of the work is to demonstrate the writing procedures of Augusto Abelaira as susceptible techniques to represent conceptions of life and of the world able to translate a social demand, that are, ultimately, writing programs appropriate to the envisioned transformations. Therefore, there is not one unique neo-realistic writing program, but there is a neo-realistic aesthetics which is the literary neo-realism itself that the works of Augusto Abelaira helps to compose. Keywords: Augusto Abelaira; Intellectual writer; Neo-realism.
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OBJECTIVE: To evaluate the scored Patient-generated Subjective Global Assessment (PG-SGA) tool as an outcome measure in clinical nutrition practice and determine its association with quality of life (QoL). DESIGN: A prospective 4 week study assessing the nutritional status and QoL of ambulatory patients receiving radiation therapy to the head, neck, rectal or abdominal area. SETTING: Australian radiation oncology facilities. SUBJECTS: Sixty cancer patients aged 24-85 y. INTERVENTION: Scored PG-SGA questionnaire, subjective global assessment (SGA), QoL (EORTC QLQ-C30 version 3). RESULTS: According to SGA, 65.0% (39) of subjects were well-nourished, 28.3% (17) moderately or suspected of being malnourished and 6.7% (4) severely malnourished. PG-SGA score and global QoL were correlated (r=-0.66, P<0.001) at baseline. There was a decrease in nutritional status according to PG-SGA score (P<0.001) and SGA (P<0.001); and a decrease in global QoL (P<0.001) after 4 weeks of radiotherapy. There was a linear trend for change in PG-SGA score (P<0.001) and change in global QoL (P=0.003) between those patients who improved (5%) maintained (56.7%) or deteriorated (33.3%) in nutritional status according to SGA. There was a correlation between change in PG-SGA score and change in QoL after 4 weeks of radiotherapy (r=-0.55, P<0.001). Regression analysis determined that 26% of the variation of change in QoL was explained by change in PG-SGA (P=0.001). CONCLUSION: The scored PG-SGA is a nutrition assessment tool that identifies malnutrition in ambulatory oncology patients receiving radiotherapy and can be used to predict the magnitude of change in QoL.