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Barcelona, Spain

UPC , currently referred to as BarcelonaTECH and commonly named just as UPC, is the largest engineering university in Catalonia, Spain - albeit encompassing other disciplines such as mathematics and architecture.BarcelonaTECH's objectives are based on internationalization, as it is Spain's technical university with the highest number of international PhD students and Spain's university with the highest number of international master's degree students. BarcelonaTECH is a university aiming at achieving the highest degree of engineering/technical excellence and has bilateral agreements with several top-ranked European universities.The Polytechnic University of Catalonia is a member of the Top Industrial Managers for Europe network, which allows for student exchanges between leading European engineering schools. It is also a member of several university federations, including the Conference of European Schools for Advanced Engineering Education and Research and UNITECH.The university was founded in March 1971 as the Universitat Politècnica de Barcelona through the merger of engineering and architecture schools originally founded during the 19th century. As of 2007 it has 25 schools in Catalonia located in the cities of Barcelona, Castelldefels, Manresa, Sant Cugat del Vallès, Terrassa, Igualada, Vilanova i la Geltrú and Mataró. UPC has about 30,000 students and 2,500 professors and researchers.Template:When? Wikipedia.

Castellano C.,CNR Institute for Complex Systems | Pastor-Satorras R.,Polytechnic University of Catalonia
Physical Review Letters | Year: 2010

We study the threshold of epidemic models in quenched networks with degree distribution given by a power-law. For the susceptible-infected-susceptible model the activity threshold λc vanishes in the large size limit on any network whose maximum degree kmax∼ diverges with the system size, at odds with heterogeneous mean-field (HMF) theory. The vanishing of the threshold has nothing to do with the scale-free nature of the network but stems instead from the largest hub in the system being active for any spreading rate λ>1/√kmax∼ and playing the role of a self-sustained source that spreads the infection to the rest of the system. The susceptible-infected-removed model displays instead agreement with HMF theory and a finite threshold for scale-rich networks. We conjecture that on quenched scale-rich networks the threshold of generic epidemic models is vanishing or finite depending on the presence or absence of a steady state. © 2010 The American Physical Society.

Serra T.,Polytechnic University of Catalonia
Energy Economics | Year: 2011

Previous literature on volatility links between food and energy prices is scarce and mainly based on parametric approaches. This article examines these links by using a semiparametric GARCH model recently proposed by Long et al. (2011), which is essentially a nonparametric correction of the parametric conditional covariance function. The analysis focuses on price links between crude oil, ethanol and sugar prices in Brazil. Results suggest strong volatility links between the prices studied. Parametric approximations of the conditional covariance matrix may lead to misleading results that can be improved upon by using nonparametric techniques. © 2011 Elsevier B.V.

Pastor-Satorras R.,Polytechnic University of Catalonia | Castellano C.,CNR Institute for Complex Systems | Castellano C.,University of Rome La Sapienza | Van Mieghem P.,Technical University of Delft | And 2 more authors.
Reviews of Modern Physics | Year: 2015

In recent years the research community has accumulated overwhelming evidence for the emergence of complex and heterogeneous connectivity patterns in a wide range of biological and sociotechnical systems. The complex properties of real-world networks have a profound impact on the behavior of equilibrium and nonequilibrium phenomena occurring in various systems, and the study of epidemic spreading is central to our understanding of the unfolding of dynamical processes in complex networks. The theoretical analysis of epidemic spreading in heterogeneous networks requires the development of novel analytical frameworks, and it has produced results of conceptual and practical relevance. A coherent and comprehensive review of the vast research activity concerning epidemic processes is presented, detailing the successful theoretical approaches as well as making their limits and assumptions clear. Physicists, mathematicians, epidemiologists, computer, and social scientists share a common interest in studying epidemic spreading and rely on similar models for the description of the diffusion of pathogens, knowledge, and innovation. For this reason, while focusing on the main results and the paradigmatic models in infectious disease modeling, the major results concerning generalized social contagion processes are also presented. Finally, the research activity at the forefront in the study of epidemic spreading in coevolving, coupled, and time-varying networks is reported. © 2015 American Physical Society. © 2015 American Physical Society.

Serrat C.,Polytechnic University of Catalonia
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2013

I make evident a method for broadband spectral-phase control of light pulses produced in high-order harmonic generation (HHG). Using a feedback loop scheme, I demonstrate that a broad spectral region of the HHG output field can be coherently added to the intense infrared driving pulse with optimal attenuation and time delay parameters to control the phase of the HHG field generated in a second interaction region. I provide computational evidence of the control scheme by considering an optimal flattening of the spectral phase for the production of isolated attosecond pulses. This is proven by considering different spectral widths and for several central photon energies, such as 36 eV, 70 eV, and 120 eV. An iterative procedure of the method allows one to obtain single pulses with less than 1.2 cycles at a central photon energy of 36 eV. This control scheme is a fundamental tool that can be implemented for amplitude and phase shaping of any suitable spectral region in HHG. © 2013 American Physical Society.

Serrat C.,Polytechnic University of Catalonia
Physical Review Letters | Year: 2013

We theoretically study the response of He atoms exposed simultaneously to an intense IR pulse and a weak extreme ultraviolet (XUV) pulse with photon energies far from the principal atomic He resonances. We find that XUV forward scattering from the nonstationary electronic wave packet promoted by the intense IR driving field is strongly enhanced as compared with the normal weak scattering from bound or free electrons. Based on this effect, we predict that large amplification of XUV radiation can be achieved in the cutoff spectral region of high-harmonic generation in He gas. © 2013 American Physical Society.

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