798 resultados para principe local-global
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The subject of climate feedbacks focuses attention on global mean surface air temperature (GMST) as the key metric of climate change. But what does knowledge of past and future GMST tell us about the climate of specific regions? In the context of the ongoing UNFCCC process, this is an important question for policy-makers as well as for scientists. The answer depends on many factors, including the mechanisms causing changes, the timescale of the changes, and the variables and regions of interest. This paper provides a review and analysis of the relationship between changes in GMST and changes in local climate, first in observational records and then in a range of climate model simulations, which are used to interpret the observations. The focus is on decadal timescales, which are of particular interest in relation to recent and near-future anthropogenic climate change. It is shown that GMST primarily provides information about forced responses, but that understanding and quantifying internal variability is essential to projecting climate and climate impacts on regional-to-local scales. The relationship between local forced responses and GMST is often linear but may be nonlinear, and can be greatly complicated by competition between different forcing factors. Climate projections are limited not only by uncertainties in the signal of climate change but also by uncertainties in the characteristics of real-world internal variability. Finally, it is shown that the relationship between GMST and local climate provides a simple approach to climate change detection, and a useful guide to attribution studies.
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In 'Local pragmatics in a Gricean framework', Mandy Simons argues that, contrary to the received view, it is possible to accommodate local pragmatic effects utilising just the mechanisms for pragmatic reasoning provided by Grice. Although I agree with this overarching claim, this paper argues that we need to be careful in our understanding of 'what is said', and the nature of communicated content in general, when deciding between local and global accounts of pragmatic effects.
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This paper provides an overview of the main insights arising from the ‘regional strategy’ literature. It also develops the contours of a new, rich research agenda for future international strategy scholarship, whereby the region should be introduced as an explicit, third geographic level of analysis, in addition to the country-level and the global level. Regional strategy analysis requires a fundamental rethink of mainstream theories in the international strategy sphere. This rethink involves, inter alia, internalization theory, with its resource-based view and transaction cost economics components, as well as the integration (I) – national responsiveness (NR) framework.
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Deviations from the average can provide valuable insights about the organization of natural systems. The present article extends this important principle to the systematic identification and analysis of singular motifs in complex networks. Six measurements quantifying different and complementary features of the connectivity around each node of a network were calculated, and multivariate statistical methods applied to identify singular nodes. The potential of the presented concepts and methodology was illustrated with respect to different types of complex real-world networks, namely the US air transportation network, the protein-protein interactions of the yeast Saccharomyces cerevisiae and the Roget thesaurus networks. The obtained singular motifs possessed unique functional roles in the networks. Three classic theoretical network models were also investigated, with the Barabasi-Albert model resulting in singular motifs corresponding to hubs, confirming the potential of the approach. Interestingly, the number of different types of singular node motifs as well as the number of their instances were found to be considerably higher in the real-world networks than in any of the benchmark networks. Copyright (C) EPLA, 2009
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Global optimization seeks a minimum or maximum of a multimodal function over a discrete or continuous domain. In this paper, we propose a hybrid heuristic-based on the CGRASP and GENCAN methods-for finding approximate solutions for continuous global optimization problems subject to box constraints. Experimental results illustrate the relative effectiveness of CGRASP-GENCAN on a set of benchmark multimodal test functions.
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In this work we prove that the global attractors for the flow of the equation partial derivative m(r, t)/partial derivative t = -m(r, t) + g(beta J * m(r, t) + beta h), h, beta >= 0, are continuous with respect to the parameters h and beta if one assumes a property implying normal hyperbolicity for its (families of) equilibria.
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O estudo tem como questão central o debate sobre as características do processo de globalização e das implicações sociais que dele decorrem para a esfera local. O argumento desenvolvido na análise é de que o processo de globalização seria modelado não apenas por diferentes contextos institucionais, mas também por recursos e por estratégias dos atores sociais implicados. Se, por um lado, o processo de globalização significaria a imposição de novas formas tecnológicas e organizacionais e de novas regras econômicas, por outro lado, interagiria com conjunturas políticas e de mercado, com os diferentes recursos dos atores sociais e com valores e ideologias locais, configurando realidades diversas e processos contraditórios de mudança social. Neste sentido, as mudanças decorrentes da presença de agentes globais conteriam, potencialmente, riscos e oportunidades cuja realização dependeria da capacidade dos atores locais de interagir com aquelas forças e agentes. As relações de poder entre atores globais e locais seriam assimétricas, submetendo estes a intensas e inesperadas mudanças que podem ser traumáticas. Contudo, os atores locais tenderiam a reagir, nas possibilidades de seus recursos e nos horizontes de seus valores, às novas regras e condições, tentando criar alternativas e, com isso, beneficiar-se das novas relações que se estabelecem. Ao sublinhar a complexidade, a contingência e a diversidade das relações global-local, o enfoque teórico-interpretativo adotado no estudo questiona argumentos de que a globalização decorre puramente da “lógica” ou dos “interesses do capital” ou de que as forças da globalização estimulariam integração econômica e social, com efeitos homogêneos. A questão das relações global-local é discutida mediante a análise da instalação, no ano de 2000, do novo pólo automobilístico de Gravataí (RS) – liderado por uma unidade montadora da General Motors do Brasil (GMB) - e de seus reflexos na reestruturação do processo produtivo e nas relações de trabalho e de emprego em empresas fornecedoras locais. A despeito de, no caso em estudo, a GMB não desenvolver programas de apoio à capacitação de fornecedores e de as instituições locais mostrarem-se tímidas e seletivas relativamente a essa tarefa, a montadora requer novos padrões de escala de compras, de qualidade dos componentes, de custos e preços e de valor agregado ao produto, que tendem a estimular a expansão das atividades, a reestruturação do processo produtivo e a flexibilização das relações de trabalho e de emprego, em empresas locais. Ademais, as mudanças verificadas nas empresas locais tendem a assumir diferentes trajetórias que variam de acordo com os seus recursos e estratégias (capital, tipo de produto e tecnologia, experiência no mercado global). Tais constatações autorizam concluir que o processo de globalização é uma imposição, porém, ele não se desenvolve de maneira unilateral, nem produz efeitos homogêneos sobre os atores locais, requerendo destes o aprendizado sobre como mover-se nessa nova realidade e dela obter benefícios coletivos.
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In this paper, we investigated the nonlinear vibrations of a Non-ideal (NIS) electromechanical absorber (NEVA), taking into account a modified mathematical model of (MR) Damper. We observed the presence of the Sornmerfeld effect (it is the steady state frequencies of the DC motor, which it will usually increasing as more power (Voltage) is given to it, in a step-by-step fashion. When a resonance condition it is reached, the better part of this energy it is consumed to generate large amplitude vibrations of the foundation, without sensible change of the motor frequency). The obtained results, by using numerical and analytical simulations, were discussed, in details.
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This paper deals with an energy pumping that occurs in a (MEMS) Gyroscope nonlinear dynamical system, modeled with a proof mass constrained to move in a plane with two resonant modes, which are nominally orthogonal. The two modes are ideally coupled only by the rotation of the gyro about the plane's normal vector. We also developed a linear optimal control design for reducing the oscillatory movement of the nonlinear systems to a stable point.
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Amorphous and crystalline thin films of Mn-doped(0.5%-10%) GaAs and crystalline thin films of Zn1-xCoxO(x = 3%-20%) were investigated by means of magnetic susceptibility and electron spin resonance (ESR). For the Mn-doped GaAs samples, our results show the absence of ferromagnetic ordering for the amorphous films in the 300 > T > 2 K temperature range, in contrast to the ferromagnetism found in crystalline films for T-C < 110 K. A single ESR line with a temperature independent g-value (g similar to 2) is observed for the amorphous films, and the behavior of this ESR linewidth depends on the level of crystallinity of the film. For the Mn-doped GaAs crystalline films, only a ferromagnetic mode is observed for T < TC when the film is ferromagnetic. Turning now the Zn1-xCoxO films, ferromagnetic loops were observed at room temperature for these films. The magnetization data show an increasing of the saturation magnetization M. as a function of x reaching a maximum value for x approximate to 10%. ESR experiments at T = 300 K in the same films show a strong anisotropic ferromagnetic mode (FMR) for x = 0.10.
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SMART material systems offer great possibilities in terms of providing novel and economical solutions to engineering problems. The technological advantages of these materials over traditional ones are due to their unique microstructure and molecular properties. Smart materials such as shape memory alloys (SMA), has been used in such diverse areas of engineering science, nowadays. In this paper, we present a numerical investigation of the dynamics interaction of a nonideal structure (NIS). We analyze the phenomenon of the passage through resonance region in the steady state processes. We remarked that this kind of problem can lead to the so-called Sommerfeld effect: steady state frequencies of the DC motor will usually increase as more power (voltage) is given to it in a step-by-step fashion. When a resonance condition with the structure it is reached, the better part of this energy it is consumed to generate large amplitude vibrations of the foundation without sensible change of the motor frequency as before. The results obtained by using numerical simulations are discussed in details. Copyright © 2009 by ASME.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)