Can a Habit Formation Model really explain the forward premium anomaly?

Verdelhan (2009) shows that if one is to explain the foreign exchange forwardpremium behavior using Campbell and Cochrane (1999)'s habit formation modelone must specify it in such a way to generate pro-cyclical short term risk free rates.At the calibration procedure, we show that this is only possible in Campbell andCochrane's framework under implausible parameters speci cations given that theprice-consumption ratio diverges in almost all parameters sets. We, then, adoptVerdelhan's shortcut of xing the sensivity function (st) at its steady state level toattain a nite value for the price-consumption ratio and release it in the simulationstage to ensure pro-cyclical risk free rates. Beyond the potential inconsistenciesthat such procedure may generate, as suggested by Wachter (2006), with pro-cyclical risk free rates the model generates a downward sloped real yield curve,which is at odds with the data.

Simplified model for the non-linear behaviour representation of reinforced concrete columns under biaxial bending

In the present paper a simplified model is proposed for the force-deformation behaviour of reinforced concrete members under biaxial loading combined with axial force. The starting point for the model development was an existing fixed-length plastic hinge element model that accounts for the non-linear hysteretic behaviour at the element end-sections, characterized by trilinear moment-curvature laws. To take into account the section biaxial behaviour, the existing model was adopted for both orthogonal lateral directions and an interaction function was introduced to couple the hysteretic response of both directions. To calibrate the interaction function it were used numerical results, obtained from fibre models, and experimental results. For the parameters identification, non-linear optimization approaches were adopted, namely: the gradient based methods followed by the genetic, evolutionary and nature-inspired algorithms. Finally, the simplified non-linear model proposed is validated through the analytical simulation of biaxial test results carried out in full-scale reinforced concrete columns

Contributions from Dilatonic Strings to the Flat Behaviour of the Rotational Curves in Galaxies

We analyse the flat behaviour of the rotational curves in some galaxies in the framework of a dilatonic, current-carrying string. We determine the expression of the tangential velocity of test objects following a stable circular equatorial orbit in this spacetime.Comment: This version to be published in the Int. Journal of Modern Phys.

Evidential Communities for Complex Networks

Community detection is of great importance for understand-ing graph structure in social networks. The communities in real-world networks are often overlapped, i.e. some nodes may be a member of multiple clusters. How to uncover the overlapping communities/clusters in a complex network is a general problem in data mining of network data sets. In this paper, a novel algorithm to identify overlapping communi-ties in complex networks by a combination of an evidential modularity function, a spectral mapping method and evidential c-means clustering is devised. Experimental results indicate that this detection approach can take advantage of the theory of belief functions, and preforms good both at detecting community structure and determining the appropri-ate number of clusters. Moreover, the credal partition obtained by the proposed method could give us a deeper insight into the graph structure

Medicamentos e ingestión de alcohol: estudio del almotriptan

Diversos investigadors de l'Hospital Universitari Germans Trias i Pujol i de l'empresa farmacèutica Laboratorios Almirall han dut a terme un estudi per comprovar quin és l'efecte terapèutic de l'almotriptan -un fàrmac utilitzat en el tractament de les crisis de migranya- en relació al consum d'alcohol. Els resultats obtinguts en la recerca indiquen que no és necessari modificar la dosificació del medicament quan s'administra en un pacient en què la crisi de migranya s'ha produït després de la presa d'alcohol.Diversos investigadores del Hospital Universitario Germans Trias i Pujol y de la empresa farmacéutica Laboratorios Almirall han llevado a cabo un estudio para comprobar cuál es el efecto terapéutico del almotriptan - un fármaco utilizado en el tratamiento de las crisis de migraña- en relación al consumo de alcohol. Los resultados obtenidos en la investigación indican que no es necesario modificar la dosificación del medicamento cuando se administra en un paciente en que la crisis de migraña se ha producido después de la ingestión de alcohol

Interface gráfico para análise não-linear de pórticos planos sujeitos a cargas dinâmicas e/ou estáticas

Apesar dos avanços ocorridos na programação ao nível da análise estrutural nãolinear, a sua visualização gráfica ao nível de pré e pós-processamento não se encontra muito desenvolvid. Reconhecida esta lacuna, foi criado um processador gráfico, VISUALANL, orientado para um programa de análise dinâmica não-linear de estruturas reticuladas planas, PORANL. Este programa permite representar o comportamento não-linear e histerético, associado à flexão, de elementos de betão armado, para solicitações estáticas e dinâmicas. Esta ferramenta gráfica permite gerar a geometria da estrutura, assim como definir as características das secções, introduzir apoios, gerar casos de carga e visualizar os resultados, modos de vibração, diagramas de esforços, deformadas, evoluções no tempo de esforços, (deslocamentos e deformações)