A zero-thickness mortar/ interface formulation with application to fracture mechanics

A zero-thickness mortar/interface element formulation is briefly described and demonstrated. This element may be considered as an extension of traditional zero-thickness interface element, in order to represent material interfaces located in between subdomains with non-matching FE meshes. In the context of small strain analysis, these elements may be equipped with the same type of constitutive laws as traditional interface elements. Therefore, if friction or fracture-mechanics-based laws are adopted, mortar/interface elements may be used to represent frictional sliding or cracking following the lines (surfaces) along which they have been pre-inserted. Two basic verification examples of this type are presented, showing that the model can correctly represent uniform states of stress and deformation when connecting unmatched mesh subdomains

A zero-thickness mortar / Interface formulation with application to fracture mechanics

A zero-thickness mortar/interface element formulation is briefly described and demonstrated. This element may be considered as an extension of traditional zero-thickness interface element, in order to represent material interfaces located in between subdomains with non-matching FE meshes. In the context of small strain analysis, these elements may be equipped with the same type of constitutive laws as traditional interface elements. Therefore, if friction or fracture-mechanics-based laws are adopted, mortar/interface elements may be used to represent frictional sliding or cracking following the lines (surfaces) along which they have been pre-inserted. Two basic verification examples of this type are presented, showing that the model can correctly represent uniform states of stress and deformation when connecting unmatched mesh subdomains.Postprint (published version

How are you doing in your grandpa’s country? Labour market performance of Latin American immigrants in Spain.

This paper analyses wage differentials between local and foreign workers from Latin America and the Caribbean in Spain, which was traditionally a country of emigrants, being precisely Hispanic America the main host region of Spanish migrants during the 19th and 20th centuries. In addition, we also compute earnings. The paper exploits the Earnings Structure Survey 2006, which is the first nationally representative sample of both foreign and Spanish employees. Using the Machado-Mata econometric procedure, wage differentials between locals and foreigners are decomposed into the gap related to characteristics and the one due to different returns on endowments (i.e., discrimination). First, we find that, in absolute terms, the latter component grows across wage distribution, reflecting the existence of a kind of glass ceiling. Second, there seem not to be significant wage gap between Latin American and the last of foreign employees, probably because non-native workers are employed in low-skill jobs.Immigration; Wage differentials; Latin America; Spain; Quantile regression.

From guests to hosts: a first whole picture of immigrant-native wage differentials in Spain

This article analyses the immigrant-native wage differentials in Spain, which only recently has become a host country. The paper exploits the Earnings Structure Survey 2006, which is the first nationally representative sample of both foreigner and Spaniard employees. Using the Machado-Mata econometric procedure, wage differentials between locals and foreigners are decomposed into the gap related to characteristics and that due to different returns to endowments (i.e., discrimination). We found that, in absolute terms, the latter component grows across wage distribution, reflecting the existence of a kind of glass ceiling consistent with the evidence of over-education found by previous research.immigration; wage differentials; Spain; quantile regression

An analysis of the competitiveness of the furniture industry in the Valencian Community

In the international economic context, some changes affecting directly the behaviour of industries are taking place. These world level changes are due, in part, to the so called globalization process, that has modified the production activity, growing up the rivalry between firms. If we want to respond with success to the new situation a clear consecuence must generate, and that is the need to maintain a higher level of competitiveness in an industrial area. It is proven that there are competitive industries with a high employment level, a high productivity rate, and an important amount of exports. These industries are the basis of the regional economy, even tha national and, therefore, it is necesary to know the industry structure, and the reasons why a competitive advantage can be stablished. In our opinion, this is the way to get a wide vision of the dynamics of the system. In other words, we need to know which aspects, endogenous or exogenous, can give a competitive advantage to the industry. Spain in general, and in the Valencian Comunity, in particular, has an export-trade orientated structure: The tile industry, the shoe industry or the furniture one, are good examples of competitive industries, which are considered strategic parts of the valencian economic dynamics, even though they are also considered “traditional industries”. We have choosen the furniture industry to analize its competitiveness. The hypothesis that we want to contrast is that “in the Valencian Comunity, or more precisely, in the area of Valencia, an hightly competitive industrial cluster has been formed (defined as critical masses of unususal competitive success in particular fields by Porter, 1998). The relationships between its memebers, the competition and cooperation established among them, and the innovation generated inside it, implicate a dynamic behavior of the firms of the cluster and the competitiveness of the whole industry. In this study, we demonstrate the validity of the “cluster model” to explain competitiveness of the Valencian furniture industry, and how the factors that are implied are local.

Equational Characterization of Covariant-Contravariant Simulation and Conformance Simulation Semantics

Covariant-contravariant simulation and conformance simulation generalize plain simulation and try to capture the fact that it is not always the case that "the larger the number of behaviors, the better". We have previously studied their logical characterizations and in this paper we present the axiomatizations of the preorders defined by the new simulation relations and their induced equivalences. The interest of our results lies in the fact that the axiomatizations help us to know the new simulations better, understanding in particular the role of the contravariant characteristics and their interplay with the covariant ones; moreover, the axiomatizations provide us with a powerful tool to (algebraically) prove results of the corresponding semantics. But we also consider our results interesting from a metatheoretical point of view: the fact that the covariant-contravariant simulation equivalence is indeed ground axiomatizable when there is no action that exhibits both a covariant and a contravariant behaviour, but becomes non-axiomatizable whenever we have together actions of that kind and either covariant or contravariant actions, offers us a new subtle example of the narrow border separating axiomatizable and non-axiomatizable semantics. We expect that by studying these examples we will be able to develop a general theory separating axiomatizable and non-axiomatizable semantics.Comment: In Proceedings SOS 2010, arXiv:1008.190

Estrategias territoriales ante la crisis: cultura del territorio y calidad institucional

Producción CientíficaAnalysis and interpretation of the factors responsible for the economic crisis in Spain in order to assess their impact on the space and its significance in the strategy of public policy. Fundamentally, the need to strengthen the culture of the territory and to advance the quality of institutions as requirements to correct the mistakes that have led to the traumatic effects caused by the crisis is underlined