8 resultados para Adequate Family

em Repositório Científico do Instituto Politécnico de Lisboa - Portugal


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Family firm is a field of growing interest. The aim of this article is to understand whether CEOs identity impacts family firm’s stock returns. From a sample of Portuguese and Spanish family firms findings show that who manages the firms result in significantly different risk exposure. Moreover, we find that the abnormal return found by Fahlenbrach (2009) to founder-controlled firms disappear when we use valueweighted portfolios and include two new factors: market aggregate illiquidity and debt intensity to the four-factor Carhart model. Finally, our results explain why the majority of family firm is controlled by its founder.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Tribimaximal leptonic mixing is a mass-independent mixing scheme consistent with the present solar and atmospheric neutrino data. By conveniently decomposing the effective neutrino mass matrix associated to it, we derive generic predictions in terms of the parameters governing the neutrino masses. We extend this phenomenological analysis to other mass-independent mixing schemes which are related to the tribimaximal form by a unitary transformation. We classify models that produce tribimaximal leptonic mixing through the group structure of their family symmetries in order to point out that there is often a direct connection between the group structure and the phenomenological analysis. The type of seesaw mechanism responsible for neutrino masses plays a role here, as it restricts the choices of family representations and affects the viability of leptogenesis. We also present a recipe to generalize a given tribimaximal model to an associated model with a different mass-independent mixing scheme, which preserves the connection between the group structure and phenomenology as in the original model. This procedure is explicitly illustrated by constructing toy models with the transpose tribimaximal, bimaximal, golden ratio, and hexagonal leptonic mixing patterns.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In the two-Higgs-doublet model (THDM), generalized-CP transformations (phi(i) -> X-ij phi(*)(j) where X is unitary) and unitary Higgs-family transformations (phi(i) -> U-ij phi(j)) have recently been examined in a series of papers. In terms of gauge-invariant bilinear functions of the Higgs fields phi(i), the Higgs-family transformations and the generalized-CP transformations possess a simple geometric description. Namely, these transformations correspond in the space of scalar-field bilinears to proper and improper rotations, respectively. In this formalism, recent results relating generalized CP transformations with Higgs-family transformations have a clear geometric interpretation. We will review what is known regarding THDM symmetries, as well as derive new results concerning those symmetries, namely how they can be interpreted geometrically as applications of several CP transformations.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Dissertação apresentada à Escola Superior de Educação de Lisboa para obtenção do grau de mestre em Ciências da Educação - Especialidade Intervenção Precoce

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Neste artigo apresentam-se os resultados do projecto de investigação/acção Promoção da qualidade dos cuidados prestados em amas e creche familiar (resposta enquadrada pelo Decreto-Lei n.º158/84). É um estudo exploratório, de carácter longitudinal, que teve como principais objectivos: (1) avaliar a qualidade da resposta creche familiar em duas instituições do Distrito de Lisboa; (2) analisar se variáveis como a idade, nível de escolaridade e tempo de experiência das amas, o rácio TE/ama e a idade das crianças estavam associadas à qualidade de cuidados prestada; (3) sistematizar os passos de um programa de promoção da qualidade baseado numa metodologia de consultoria; e (4) determinar os efeitos do programa de consultoria na promoção da qualidade. Participaram neste projecto 10 amas enquadradas na creche familiar de um centro infantil do Centro Distrital de Segurança Social de Lisboa, 21 amas de centros infantis da Santa Casa da Misericórdia de Lisboa e os Técnicos de Enquadramento responsáveis pelo apoio técnico. A Family Child Care Environment Rating Scale, Revised Edition (FCCERS-R) de Harms, Cryer e Clifford (2007), traduzida pela equipa de investigação, foi o principal instrumento utilizado. A recolha de dados decorreu em três momentos: (1) avaliação inicial; (2) reunião de consultoria; e (3) avaliação final.Os resultados encontrados mostram que a qualidade dos cuidados prestados pelas amas é adequada/mínima, com excepção dos itens relacionados com a interacção ama-criança onde a qualidade é boa, sendo a subescala actividades aquela onde foram encontrados valores mais baixos. Não foram encontradas associações significativas entre a qualidade e o tempo experiência das amas. Relativamente às restantes variáveis – idade das amas, rácio TE/ama e idade das crianças – encontraram-se algumas associações com a qualidade global e em algumas das subescalas da FCCERS-R. Foram encontradas diferenças entre os dados da 1ª e da 2ª observação que parecem poder associar-se ao processo de consultoria implementado.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Discrete data representations are necessary, or at least convenient, in many machine learning problems. While feature selection (FS) techniques aim at finding relevant subsets of features, the goal of feature discretization (FD) is to find concise (quantized) data representations, adequate for the learning task at hand. In this paper, we propose two incremental methods for FD. The first method belongs to the filter family, in which the quality of the discretization is assessed by a (supervised or unsupervised) relevance criterion. The second method is a wrapper, where discretized features are assessed using a classifier. Both methods can be coupled with any static (unsupervised or supervised) discretization procedure and can be used to perform FS as pre-processing or post-processing stages. The proposed methods attain efficient representations suitable for binary and multi-class problems with different types of data, being competitive with existing methods. Moreover, using well-known FS methods with the features discretized by our techniques leads to better accuracy than with the features discretized by other methods or with the original features. (C) 2013 Elsevier B.V. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The synthesis of two new inherently chiral calix[4]arenes (ICCs, 1 and 2), endowed with electron-rich concave surfaces, has been achieved through the desymmetrization of a lower rim distal-bridged oxacyclophane (OCP) macrocycle. The new highly emissive ICCs were resolved by chiral HPLC, and the enantiomeric nature of the isolated antipodes proved by electronic circular dichroism (CD). Using time-dependent density functional calculations of CD spectra, their absolute configurations were established. NMR studies with (S)-Pirkle's alcohol unequivocally showed that the host-guest interactions occur in the chiral pocket comprehending the calix-OCP exo cavities and the carbazole moieties.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Dissertação apresentada à Escola Superior de Educação de Lisboa para obtenção de grau de mestre em Educação Especial