10,372 research outputs found
The rotational shear layer inside the early red-giant star KIC 4448777
We present the asteroseismic study of the early red-giant star KIC 4448777,
complementing and integrating a previous work (Di Mauro et al. 2016), aimed at
characterizing the dynamics of its interior by analyzing the overall set of
data collected by the {\it Kepler} satellite during the four years of its first
nominal mission. We adopted the Bayesian inference code DIAMOND (Corsaro \& De
Ridder 2014) for the peak bagging analysis and asteroseismic splitting
inversion methods to derive the internal rotational profile of the star. The
detection of new splittings of mixed modes, more concentrated in the very inner
part of the helium core, allowed us to reconstruct the angular velocity profile
deeper into the interior of the star and to disentangle the details better than
in Paper I: the helium core rotates almost rigidly about 6 times faster than
the convective envelope, while part of the hydrogen shell seems to rotate at a
constant velocity about 1.15 times lower than the He core. In particular, we
studied the internal shear layer between the fast-rotating radiative interior
and the slow convective zone and we found that it lies partially inside the
hydrogen shell above and extends across the core-envelope
boundary. Finally, we theoretically explored the possibility for the future to
sound the convective envelope in the red-giant stars and we concluded that the
inversion of a set of splittings with only low-harmonic degree , even
supposing a very large number of modes, will not allow to resolve the
rotational profile of this region in detail.Comment: accepted for publication on Ap
Aproveitamento hidroelétrico da bacia do Douro: um olhar crítico
No presente artigo, faz-se uma breve resenha histórica da evolução do aproveitamento dos recursos hídricos nacionais em termos hidroelétricos, bem como uma análise da situação atual. Dá-se particular destaque à vertente hidroelétrica, mas não se limita a ela. Mostra-se a insuficiência das obras hidráulicas até agora realizadas a nível das nossas principais bacias, em particular no caso da bacia portuguesa do Douro, e alerta-se para as nefastas consequências que poderiam advir caso a situação não se alterasse. O PNBEPH aprovado em 2007 veio contribuir para relançar esta importante temática, a qual pareceu inexplicavelmente esquecida durante quase duas décadas, por parte das entidades às quais competia zelar pelo interesse público e pela salvaguarda dos legítimos direitos e expectativas das populações nacionais
What makes mass housing representations so different, so appealing? The French grands ensembles in comic-strip form
References to mass housing complexes tend to balance between their generally unknown realities and the pervasive power of their representations. These are often nourished by emotional experiences conveyed by words and images in mass media and political discourse – especially when it comes to ghettos or problematic suburbs – and multiple arrays of commercial, documentary, and fictional depictions of everyday realities or aspirational imaginaries. Complementarily, different media types entered middle- and lower-class houses, rendering these mediations bidirectional by progressively conquering their place in the domestic scene. Besides, the history of access to housing runs parallel and often intertwined with the history of media, rendering mass housing an object of mass media and a pop culture subject, entangling different and often contradictory representations.
Simultaneously the country of bande dessinée and the crisis of the banlieues, France is a particularly revealing example. Since the mid-1960s, comic strips acquired a special status in French society that rendered it an accurate cultural barometer of its culture. Alongside, France extensively built social housing estates in the outskirts of its major cities throughout Les Trente Glorieuses. As a result, these grands ensembles often became highly stigmatised and mediatised places with their bars and towers, frequently depicted in cinema, literature, comic strips, and other art forms.
This paper aims to discuss the state of the art of the presence of social housing estates in French comics and present an array of comic books – produced since the 1970s – that depict these architectures and illustrate their social questions. These examples reveal the qualities and expose the contradictions of comics and the seductive power of the medium to explore the urban context of the banlieue, either when narrating its dystopic and violent environments or when enhancing the anthropological and visual qualities of these suburban settings
A Bayesian estimate of the CMB-large-scale structure cross-correlation
Evidences for late-time acceleration of the Universe are provided by multiple
probes, such as Type Ia supernovae, the cosmic microwave background (CMB) and
large-scale structure (LSS). In this work, we focus on the integrated
Sachs--Wolfe (ISW) effect, i.e., secondary CMB fluctuations generated by
evolving gravitational potentials due to the transition between, e.g., the
matter and dark energy (DE) dominated phases. Therefore, assuming a flat
universe, DE properties can be inferred from ISW detections. We present a
Bayesian approach to compute the CMB--LSS cross-correlation signal. The method
is based on the estimate of the likelihood for measuring a combined set
consisting of a CMB temperature and a galaxy contrast maps, provided that we
have some information on the statistical properties of the fluctuations
affecting these maps. The likelihood is estimated by a sampling algorithm,
therefore avoiding the computationally demanding techniques of direct
evaluation in either pixel or harmonic space. As local tracers of the matter
distribution at large scales, we used the Two Micron All Sky Survey (2MASS)
galaxy catalog and, for the CMB temperature fluctuations, the ninth-year data
release of the Wilkinson Microwave Anisotropy Probe (WMAP9). The results show a
dominance of cosmic variance over the weak recovered signal, due mainly to the
shallowness of the catalog used, with systematics associated with the sampling
algorithm playing a secondary role as sources of uncertainty. When combined
with other complementary probes, the method presented in this paper is expected
to be a useful tool to late-time acceleration studies in cosmology.Comment: 21 pages, 15 figures, 4 tables. We extended the previous analyses
including WMAP9 Q, V and W channels, besides the ILC map. Updated to match
accepted ApJ versio
SDG scoring : an analytic hierarchy process approach
The demand for non-financial information has substantially risen in the last few years. Previously, investors only considered financial information on their investment decisions but there is an increased perception that non-financial factors might provide an additional framework on which firms can be measured, which can positively impact their investment success. Due to this, multiple rating agencies have risen as providers of scores reflecting the Environmental, Social and Governance (ESG) position of firms. However, they often seen as not providing the adequate theoretical reasoning and methodological clarity, which in addition to the lack of a consensus on ESG criteria, creates the space for the development of another scoring system with a robust and clear sustainability framework underlying it. Additionally, following the implementation of the Corporate Sustainability Reporting Directive (CSRD), a broader set of firms are required to report on their environmental and social impacts. This might create an information disadvantage for non-CSRD covered firms, which has led these firms to also have the desire to report on these issues. This dissertation presents the development process of a scoring system on which non-financial performance is measured through the Sustainable Development Goals (SDGs), i.e., a robust framework and that combines both financial and non-financial information in a single value, through Multi-Criteria Decision Making, namely, the Analytic Hierarchy Process (AHP). Additionally, it also provides a base framework for firms ESG reporting.Recentemente, a procura por informação não financeiro aumentou bastante. Previamente, os investidores apenas consideravam informação financeira nas suas decisões de investimento, mas há uma crescente perceção de que fatores não financeiros podem fornecer um quadro adicional para a avaliação das empresas, podendo impactar positivamente o sucesso dos seus investimentos. Devido a isso, múltiplas agências de classificação surgiram como provedoras de pontuações que refletem a posição Ambiental, Social e de Governança (ASG) das empresas. No entanto, estas não fornecem o raciocínio teórico e clareza metodológica por trás dessas pontuações, o que, além da diferente definição de critérios ASG entre elas, cria espaço para o desenvolvimento de um outro sistema de pontuação com um quadro de sustentabilidade robusto e claro. Além disso, após a implementação da Diretiva de Relato de Sustentabilidade Corporativa (DRSC), um conjunto mais amplo de empresas é obrigado a relatar sobre os seus impactos ambientais e sociais. Isto pode criar uma desvantagem de informação para as empresas não cobertas pela DRSC, o que levou essas empresas a também terem o desejo de relatar sobre estas questões. Esta Tese apresenta o processo de desenvolvimento de um sistema de pontuação no qual o desempenho não financeiro é medido por meio dos Objetivos de Desenvolvimento Sustentável e que combina informações financeiras e não financeiras num único valor, por meio do processo de tomada de decisão multicritério, nomeadamente, o Processo Analítico Hierárquico (PAH). Além disso, também fornece um quadro básico para o relato ASG das empresas
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