982 resultados para Self-consistent field theory
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This study investigates the determinants of the fertility rate in China over the 1952-2000 period. Consistent with theory, the key explanatory variables in our fertility model are real per capita income, infant mortality rate, female illiteracy and female labour force participation rates. The long-run results and the test for cointegration are based on the Johansen (1988) and Johansen & Juselius (1990) approach. Our long-run results conform to theory in that all variables appear with their expected signs, and the dummy variable used to capture the effects of the family planning policy indicates that in the years of the policy, fertility rates have been falling by around 10-12%. Our results suggest that socio-economic development - consistent with the traditional structural hypothesis - played a key role in China's fertility transition.
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In this article, we estimate money demand functions for a panel of eight transitional economies, using quarterly data for the period 1995:01 1995 to 2005:03. We find that real M1 and real M2 and their determinants, namely real income and short-term domestic interest rate, are cointegrated, both for individual countries as well as for the panel. Long-run elasticities suggest that consistent with theory, real income positively and nominal interest rate negatively impact real money demand. Our test for panel Granger causality suggests short-run bidirectional causality between M1 and M2 and their determinants. Finally, our tests for stability of the money demand functions reveal more cases of unstable money demand functions when M2 is used as a proxy for money demand.
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We present results of a theoretical study of the effect of surface deformation on a macroscopic system composed of a solid surface interacting with a fluid drop through electrostatic double-layer forces. The analysis involves numerically solving a Laplace equation suitably modified to describe the shape of a liquid drop subjected to a repulsive double-layer force. The latter is evaluated in nonlinear mean-field theory. Some analytical results are also given. The results indicate that although deformation need not be significant on the macroscopic scale, its effect on the interaction is significant and modifies the picture usually presented in DLVO theory. The decay length of the exponential repulsion deviates marginally from the Debye length, dependent on the interfacial tension of the drop. More significantly, at separations where the double-layer force becomes comparable to the internal pressure of the drop, the net force between the two bodies, the local radius of curvature of the drop, and the amount of deformation grow abruptly. The results of this work are relevant to emulsion stability, micelle, vesicle, and cell interactions, and recent experiments on bubble-particle interaction.
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It has been proposed that a sense of control (primary control) is critical to maintaining positive and stable subjective wellbeing (SWB). As people age and control capacity presumably declines (due to physical and cognitive deterioration and increased sociocultural challenges), it is argued that the influence of secondary perceived control (or acceptance) increases to help maintain normative levels of SWB. While previous studies have typically investigated the relationship between perceived control and global estimates of satisfaction (i.e., overall life satisfaction), the present study evaluated the link between perceived control and seven key domains of satisfaction in order to obtain a more comprehensive understanding of the control-satisfaction relationship. A community-based sample of 1,317 individuals (age range: 17–92 years) was utilised to examine potential age-related differences in perceived control (primary and secondary) and satisfaction. Findings revealed that primary and secondary perceived control both increased across age, with secondary perceived control increasing at a higher rate. Primary perceived control had predictive primacy for satisfaction over secondary perceived control (consistent with theory). A moderated mediation effect was also found, suggesting that, in later life, secondary perceived control influences primary perceived control and, in turn, influences satisfaction with various domains. Therefore, while primary control is important to wellbeing, it should be acknowledged that secondary perceived control may have unique significance to the wellbeing of older adults.
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The main aim of this chapter is to provide an introduction to the theoretical work of Pierre Bourdieu, and to outline different ways in which Bourdieu’s work is influential and has been engaged with in education research and to suggest implicitly the usefulness of this work for educational researchers. In order to do this, we draw on a range of Bourdieu’s own writing published singly or with colleagues, emphasising in particular his engagements with education. Part of our treatment also deals with his wider writing that has subsequently been influential for education researchers, and in particular Bourdieu’s anthropological writing and account of practice (Bourdieu 1977, 1990), his approach to social class and cultural issues, his account of the judgement of taste and distinctions (Bourdieu, 1984), and his later politically focused writing (Bourdieu, 1989/1996, 2003, 2004c, 2005a).
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We address credit cycle dependent sovereign credit risk determinants. In our model, the spread determinants' magnitude is conditional on an unobservable endogenous sovereign credit cycle as represented by the underlying state of a Markov regime switching process. Our explanatory variables are motivated in the tradition of structural credit risk models and include changes in asset prices, interest rates, implied market volatility, gold price changes and foreign exchange rates. We examine daily frequency variations of U.S. dollar denominated Eurobond credit spreads of four major Latin American sovereign bond issuers (Brazil, Colombia, Mexico and Venezuela) with liquid bond markets during March 2000 to June 2011. We find that spread determinants are statistically significant and consistent with theory, while their magnitude remarkably varies with the state of the credit cycle. Crisis states are characterized by high spread change uncertainty and high sensitivities with respect to the spread change determinants. We further document that not only changes of local currencies, but also changes of the Euro with respect to the U.S. dollar are significant spread drivers and argue that this is consistent with the sovereigns' ability to pay.
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The effects of annealing on the microstructure, texture, tensile properties, and R value evolution of an IF steel sheet after room-temperature symmetric and asymmetric rolling were examined. Simulations were carried out to obtain R values from the experimental textures using the viscoplastic self-consistent polycrystal plasticity model. The investigation revealed the variations in the textures due to annealing and symmetric/asymmetric rolling and showed that the R values correlate strongly with the evolution of the texture. An optimum heat treatment for the balance of strength, ductility, and deep drawability was found to be at 873 K (600 _C) for 30 minutes.
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This chapter presents an account of the mediatization of education policy through a focus on the development and uptake of the knowledge economy discourse in national education policy and research settings. During the late 20th and early part of the 21st century, Australia, like other nation states around the globe, came to adopt the knowledge economy discourse as a kind of meta-policy that would help connect a variety of statistical indicators and provide direction for a number of policy areas, including education, science, and research funding. In Australia the adoption of a knowledge economy discourse was preceded by coverage from specialized sections of the quality print media, discussed broadly as a debate about the social contract that was afforded to fields charged with developing and producing national capacities for knowledge production. Such a debate mirrored similar claims by Michael Gibbons in the late 1990s, where he argued for a new social contract between science and society. Given the media coverage surrounding the uptake of the knowledge economy discourse and the promotion of the concept by the OECD, this chapter presents an account of the emergence of the knowledge economy discourse through a focus on the mediatization of the concept. The broad argument presented in this account is that what could be called “mediatization effects”, related to the promotion and adoption of policy concepts, are variable, and reach the broader public in inconsistent, time-bound, and sporadic patterns. In order to understand mediatization effects in respect of policy, the paper draws on a broad Bourdieuian informed conceptual framework to understand different kinds of fields, their logics of practice, and importantly here, cross-field effects. Specifically, the focus is on those cross-field effects related to the impact of practices within both national and global fields of journalism on national and global fields of education policy. While the case is an Australian one, the account explores general and more broadly applicable ways to understand links between the globalization and the mediatization of policy.
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The present work introduces a double inclusion elasto-plastic self-consistent (DI-EPSC) scheme for topologies in which crystals can contain subdomains (i.e. twins, etc.). The approach yields a direct coupling between the mechanical response of grains and their subdomains via a concentration relationship on mean fields derived from both the Eshelby and the Tanaka-Mori properties. The latent effect caused by twinning on the mechanical response is observed on both initially extruded and non-textured Mg alloys. For twinned grains, it is shown that deformation system activities and plastic strain distributions within twins drastically depend on the interaction with parent domains. Moreover, a quantitative study on the coupled influence of secondary slip activities on the material response is proposed. © 2014 Published by Elsevier Ltd.
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In situ neutron diffraction of two binary Mg alloys, Mg-0.5 wt.% Y and Mg-2.2 wt.% Y have been carried out in compression. The experimental data has been modelled using the elastoplastic self-consistent methodology in order to determine the critical resolved shear stress for basal slip, second-order 〈c + 〉 pyramidal slip and {101̄2} twinning. It was found that the addition of Y strengthens all three of the deformation modes examined. However, increasing the Y concentration from 0.5% to 2.2% showed no additional hardening in the basal slip and {101̄2} twinning modes, indicating that solute strengthening of these deformation modes is already exhausted by a concentration of 0.5% Y. Second-order pyramidal slip showed additional solute hardening at the higher concentration. © 2014 Published by Elsevier Ltd. on behalf of Acta Materialia Inc. All rights reserved.
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Large carnivores face serious threats and are experiencing massive declines in their populations and geographic ranges around the world. We highlight how these threats have affected the conservation status and ecological functioning of the 31 largest mammalian carnivores on Earth. Consistent with theory, empirical studies increasingly show that large carnivores have substantial effects on the structure and function of diverse ecosystems. Significant cascading trophic interactions, mediated by their prey or sympatric mesopredators, arise when some of these carnivores are extirpated from or repatriated to ecosystems. Unexpected effects of trophic cascades on various taxa and processes include changes to bird, mammal, invertebrate, and herpetofauna abundance or richness; subsidies to scavengers; altered disease dynamics; carbon sequestration; modified stream morphology; and crop damage. Promoting tolerance and coexistence with large carnivores is a crucial societal challenge that will ultimately determine the fate of Earth’s largest carnivores and all that depends upon them, including humans.
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Dr Wake presents a comprehensive thesis of Australian journalism education and training in the context of foreign aid and policy, particularly as applied in the Solomon Islands. Although it is essentially about journalism, the thesis also adds to the field of development studies. Dr Wake has used Bourdieu’s field theory to underpin her critical analysis.
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In the present study, the effect of precipitate characteristics on {101-2} extension twinning have been studied in a Z6 magnesium alloy. A strongly textured Z6 alloy plate was mechanically tested in twinning dominated orientation in solution treated and aged states. Optical microscopy, transmission electron microscopy (TEM) and visco-plastic self consistent (VPSC) modelling are used to examine the effect of precipitate characteristics on twinning. The yield stress was observed to increase by ~80. MPa during ageing and it was estimated that CRSS for twinning increased by ~29. MPa based on VPSC simulations. The increment of twin system strengthening can be attributed to back stress generated by elastically deforming particles.
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In this article, a conceptual framework and research propositions are developed to explain how microfinance provision can translate into new venture creation and existing venture growth in an emerging economy context by engendering higher levels of psychological and social capital in clients. In doing this, the extent to which microfinance institutions provide business support and opportunities for social interaction are identified as factors which may strengthen the impact of microfinance provision on psychological and social capital, especially for poor entrepreneurs in resource-constrained settings. The conceptual framework and research propositions developed will be of use to academics in designing an agenda for future empirical research. In addition, they will help policymakers and microfinance providers to better design microfinance initiatives that enhance the well-being of clients and maximise their entrepreneurial outcomes. © The Author(s) 2013.
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A preocupaçao com a questão da "qualidade e quantidade" no ensino superior no Brasil, e mais, as polêmicas levantadas em torno das funções do Ciclo Básico na Universidade Federal do Espírito Santo, conduziram ao objetivo de um estudo mais aprofundado, das dificuldades de ensinoaprendizagem sentidas na cadeira de Psicologia I. Uma pesquisa piloto orientou para os aspectos teóricos e metodológicos a serem utilizados. Partiu-se de um referencial teórico, adotando-se Karl Marx, Adam Schaff e Pierre Bourdieu, quando se pretendeu analisar a formação da consciência do homem (sua visão de mundo, de sociedade e de si próprio). A Teoria de Campo de Kurt Lewin foi usada como referencial mais específico à parte referente à aprendizagem. Procurou-se situar o problema num contexto mais amplo, nos 2o e 3o capítulos, com abordagens sobre a expansão do ensino superior no Brasil e um histórico sobre a UFES. O estudo empírico foi realizado em dois semestres letivos. Foram entrevistados professores de Psicologia I com a finalidade de constatar a sua habilitação para a função, sua satisfação profissional e a sua visão de aluno e da disciplina que leciona. Aos alunos do Ciclo Básico foram aplicados questionários e entrevistas visando a coleta de dados sobre: nível sócio-econômico, motivações a respeito da escolha profissional e sua visão da disciplina Psicologia l.Com os mesmos objetivos colheu-se dados, através de questionários, junto aos alunos do Ciclo Profissionalizante. Os resultados obtidos evidenciaram que, as dificuldades de aprendizagem não se prendiam, essencialmente, ao programa teórico que era desenvolvido como pré-requisito para outras cadeiras de Psicologia, específicas a cada curso profissionalizante. Constatou-se a necessidade de mudanças nos objeti vos e na metodologia a serem adotados pelos professores, de forma a atingir aos alunos (portadores de expectativas, idéias, sentimentos, cultura e nível sócio-econômico). Ao final da pesquisa foi proposta uma pedagogia, dirigida à equipe de Psicologia I da UFES.