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La indústria de l’automoció fabrica una gran part de components del vehicle obtinguts mitjançant el procés d’estampació en calent per tal d’obtenir components més lleugers, més resistents i amb formes més complexes. Amb aquestes característiques permet augmentar la seguretat dels ocupants del vehicle, millorar el procés de producció augmentant la rendibilitat i reduir el pes del vehicle, fet que provocarà una disminució de les emissions de CO2 i per tant, una millora mediambiental. El principal mecanisme de desgast de les matrius utilitzades per a realitzar l’estampació en calent és la transferència de material de la peça a la matriu d’estampació. En aquest treball es realitzaran assajos electroquímics amb la intenció de poder netejar aquest material que s’adhereix a les matrius d’estampació. S’ha estudiat l’acer USIBOR AlSi que és l’acer més utilitzat en el procés d’estampació, realitzant proves amb l’acer sense estampar i amb l’acer després de ser estampat.

Congenital defects can be caused by chromosomal anomalies, which are classified in numerical or structural abnormalities, depending on whether they affect, if may affect the number of chromosomes or their structure. For the correct detection of these defects before birth prenatal diagnosis is used, which allow detection in the fetus. Prenatal screening is technique that shows the pregnant women if there is a risk of suffering an aneuploidy over the total number of pregnant women in the population. Subsequently, this risk can be confirmed by a diagnostic test in cases where the risk increases. The main objective of this study is the preparation of the evaluation report of the screening program for the year 2017 at the “Laboratori Clínic Territorial de Girona” based on the calculated screening and their origin, the monitoring of positive screenings, the results of the pathological karyotypes and an analysis of the quality indicators. In addition, an analysis of the reasons for the not calculated screening due to lack of the ecography searching for possible improvement actions through the writing of a report to Obstetrics services. And finally, an analysis of how can affect the activity the implementation of the aneuploidies prenatal screening by fetal DNA in maternal blood according to the diagnostic algorithm approved by CatSalut in 2017, and the Head of Service of the “Laboratori Clínic Territorial de Girona”. More over with the analysis results, the main origins and the number of abnormal karyotypes that occurred in 2017 have been identified. The sensitivity and specificity of the aneuploidy screening program in this laboratory has also been evaluated. In addition, it was possible to identify the main reasons for the 265 screenings that were not calculated by pending ultrasound and we studied possible actions to improve the results obtained. Finally, it has been verified that the implementation of the aneuploidies screening by fetal DNA in maternal blood would mean the increase in activity and also the reduction of the number of false negatives and therefore a greater detection of a trisomy

Large-scale failures in telecommunication networks have been traditionally mitigated by attempting to preserve global connectivity in the network. However, although communication inside communities may be of high relevance, their preservation is a challenging task. To achieve this, we propose a new concept of community that combines not only the topological information of the network but also the traffic-level interaction. This new concept is then used to present six novel community-based strategies that, when working within a limited budget, are able to determine which are the best candidate nodes to protect. The strategies proposed have been tested over four different types of networks and have been compared with other well-known immunization or protection methods. Results show that community-based strategies better preserve the inner community traffic with respect to traditional approaches. Furthermore, in some cases, both global and intra-community traffic preservation is able to be improved This work is partly supported by the Spanish Ministerio de Ciencia e Innovacion through project RoGER (Robustness against large-scale failures in interdomain routing, TEC2012-32336), Juan de la Cierva subprogram grant no. JCI-2010-08322, and by the Generalitat de Catalunya through the Research Support Program project SGR-1202 and AGAUR FI-DGR 2012 grant

Network science has significantly advanced in the last decade, providing insights into the underlying structure and dynamics of complex networks. Critical infrastructures such as telecommunication networks play a pivotal role in ensuring the smooth functioning of modern day living. These networks have to constantly deal with failures of their components. In multiple failure scenarios, where traditional protection and restoration schemes are not suitable because of the quantity of resources that would be required, the concept of robustness is used in order to quantify just how good a network is under such a large-scale failure scenario. The aim of this thesis is to, firstly, investigate the current challenges that might lead to multiple failure scenarios of present day networks and, secondly, to propose novel metrics able to quantify the network robustness., La ciència de les xarxes (o network science) ha avançat significativament en l'última dècada, proporcionant coneixement sobre l'estructura subjacent i la dinàmica de les xarxes complexes (o complex networks). Infraestructures crítiques com xarxes de telecomunicacions, juguen un paper fonamental per garantir el bon funcionament de la vida moderna. Aquestes xarxes han de lidiar constantment amb fallades dels seus components. En escenaris de fallades múltiples, on els esquemes de protecció i restauració tradicionals no són adequats degut a la gran quantitat de recursos que serien necessaris, el concepte de robustesa (o robustness) s'utilitza per tal de quantificar com de bona és una xarxa quan es produeix una fallada a gran escala. L'objectiu d'aquesta tesi és, en primer lloc, investigar les amenaces actuals de les xarxes d'avui en dia que poden portar a escenaris de fallades múltiples i, en segon lloc, proposar nous indicadors capaços de quantificar la robustesa d'aquestes xarxes.

Our society nowadays is governed by complex networks, examples being the power grids, telecommunication networks, biological networks, and social networks. It has become of paramount importance to understand and characterize the dynamic events (e.g. failures) that might happen in these complex networks. For this reason, in this paper, we propose two measures to evaluate the vulnerability of complex networks in two different dynamic multiple failure scenarios: epidemic-like and cascading failures. Firstly, we present epidemic survivability (ES), a new network measure that describes the vulnerability of each node of a network under a specific epidemic intensity. Secondly, we propose cascading survivability (CS), which characterizes how potentially injurious a node is according to a cascading failure scenario. Then, we show that by using the distribution of values obtained from ES and CS it is possible to describe the vulnerability of a given network. We consider a set of 17 different complex networks to illustrate the suitability of our proposals. Lastly, results reveal that distinct types of complex networks might react differently under the same multiple failure scenario This work is partially supported by Spanish Ministry of Science and Innovation projects TEC 2012-32336 and MTM 2011-27739-C04-03, SGR-1202, AGAUR FI-DGR 2012 and BE-DGR 2012 grants (M. M.)

The enlargement of the European Union to 25 members implies that relative position of Andalusia will improve with regard to the new GDP per capita average. This fact may derive a reduction in structural funds support for this Spanish region objective 1. This paper is focused in the ex-post assessment of the CSF 1994–99 in Andalusia. Direct and indirect effects, as well as cross-border leakage are analysed. We aim to compare stimuli induced from structural funds in the rest of the national economy with those remaining in Andalusia. If effects on the rest of Spain were important in relative terms, the central idea of regional policy, which defines community convergence tools, would be questioned. Results show evidences for this hypothesis in the case of Andalusia, given the importance of the effects generated in the rest of Spain and the biases of CSF funds towards sectors with a high need for imports, some of which are characterized by an intensive use of the region’s natural resources. Key Words: Structural Funds; Ex-post Evaluation; Convergence; Input-Output; Cross-border leakages. JEL classification: C67; C82; R58