Institution
Polytechnic University of Catalonia
Education•Barcelona, Spain•
About: Polytechnic University of Catalonia is a education organization based out in Barcelona, Spain. It is known for research contribution in the topics: Finite element method & Population. The organization has 16006 authors who have published 45325 publications receiving 949306 citations. The organization is also known as: UPC - BarcelonaTECH & Technical University of Catalonia.
Topics: Finite element method, Population, Context (language use), Computer science, Nonlinear system
Papers published on a yearly basis
Papers
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University College London1, Pierre-and-Marie-Curie University2, Blaise Pascal University3, Leibniz Association4, Barcelona Supercomputing Center5, Polytechnic University of Catalonia6, Weizmann Institute of Science7, Paul Sabatier University8, University of Oxford9, International Centre for Theoretical Physics10
TL;DR: In this paper, a comparison of five regional atmospheric models with dust modules is made, in terms of their simulation of meteorology, dust emission and transport, focusing on a 3-day dust event over the Bodele depression in northern Chad, the world's single most important dust source.
Abstract: Mineral dust aerosols play an important role in the climate system. Coupled climate-aerosol models are an important tool with which to quantify dust fluxes and the associated climate impact. Over the last decade or more, numerous models have been developed, both global and regional, but to date, there have been few attempts to compare the performance of these models. In this paper a comparison of five regional atmospheric models with dust modules is made, in terms of their simulation of meteorology, dust emission and transport. The intercomparison focuses on a 3-day dust event over the Bodele depression in northern Chad, the world's single most important dust source. Simulations are compared to satellite data and in situ observations from the Bodele Dust Experiment (BoDEx 2005). Overall, the models reproduce many of the key features of the meteorology and the large dust plumes that occur over the study domain. However, there is at least an order of magnitude range in model estimates of key quantities including dust concentration, dust burden, dust flux, and aerosol optical thickness. As such, there remains considerable uncertainty in model estimates of the dust cycle and its interaction with climate. This paper discusses the issues associated with partitioning various sources of model uncertainty.
148 citations
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TL;DR: In this article, a proof of the existence of invariant tori with a Diophantine rotation vector for Hamiltonian systems is given, which is based on the use of the geometric properties of Hamiltonian system which do not require the system either to be written in action-angle variables or to be a perturbation of an integrable one.
Abstract: We give a proof of a KAM theorem on existence of invariant tori with a Diophantine rotation vector for Hamiltonian systems. The method of proof is based on the use of the geometric properties of Hamiltonian systems which, in particular, do not require the Hamiltonian system either to be written in action-angle variables or to be a perturbation of an integrable one. The proposed method is also useful to compute numerically invariant tori for Hamiltonian systems. We also prove a translated torus theorem in any number of degrees of freedom.
148 citations
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TL;DR: In this article, a reconfigurable antenna capable of independently reconfiguring the operating frequency, radiation pattern and polarization is presented, where a switched grid of small metallic patches known as pixel surface is used as a parasitic layer to provide reconfiguration capabilities.
Abstract: This communication presents a reconfigurable antenna capable of independently reconfiguring the operating frequency, radiation pattern and polarization. A switched grid of small metallic patches, known as pixel surface, is used as a parasitic layer to provide reconfiguration capabilities to existing antennas acting as driven element. The parasitic pixel layer presents advantages such as low profile, integrability and cost-effective fabrication. A fully operational prototype has been designed, fabricated and its compound reconfiguration capabilities have been characterized. The prototype combines a patch antenna and a parasitic pixel surface consisting of 6 $\,\times\,$ 6 pixels, with an overall size of $0.6 \lambda \times 0.6 \lambda$ and 60 PIN-diode switches. The antenna simultaneously tunes its operation frequency over a 25% frequency range, steers the radiation beam over ${\pm 30^\circ}$ in E and H-planes, and switches between four different polarizations ( ${\mathhat{\rm x}},$ ${\mathhat{\rm y}}$ , LHCP, RHCP). The average antenna gain among the different parameter combinations is 4 dB, reaching 6–7 dB for the most advantageous combinations. The distance between the driven and the parasitic layers determines the tradeoff between frequency tuning range (12% to 25%) and radiation efficiency (45% to 55%).
148 citations
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TL;DR: In this article, the early age hydration mechanisms of accelerated CEM I pastes were evaluated using liquid phase analysis, conductimetry, isothermal calorimetry and in situ XRD and SEM.
148 citations
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TL;DR: A dramatic enhancement of the monovalent/divalent cation selectivities of Nafion 115 membranes through coating with multilayer poly(4-styrenesulfonate) (PSS)/protonated poly(allylamine) (PAH) films is reported.
Abstract: Electrodialysis (ED) membranes typically exhibit modest selectivities between monovalent and divalent ions. This paper reports a dramatic enhancement of the monovalent/divalent cation selectivities of Nafion 115 membranes through coating with multilayer poly(4-styrenesulfonate) (PSS)/protonated poly(allylamine) (PAH) films. Remarkably, K+/Mg2+ ED selectivities reach values >1000, and similar monovalent/divalent cation selectivities occur with feed solutions containing K+ and Ca2+. For comparison, the corresponding K+/Mg2+ selectivity of bare Nafion 115 is only 1.8 ± 0.1. However, with 0.01 M KNO3 and 0.01 M Mg(NO3)2 in the source phase, as the applied current density increases from 1.27 to 2.54 mA cm–2, the K+/Mg2+ selectivities of coated membranes decrease from >1000 to 22. Water-splitting at strongly overlimiting current densities may lead to a local pH increase close to the membrane surface and alter film permeability or allow passage of Mg(OH)x species to decrease selectivity. When the source phase co...
148 citations
Authors
Showing all 16211 results
Name | H-index | Papers | Citations |
---|---|---|---|
Frede Blaabjerg | 147 | 2161 | 112017 |
Carlos M. Duarte | 132 | 1173 | 86672 |
Ian F. Akyildiz | 117 | 612 | 99653 |
Josep M. Guerrero | 110 | 1197 | 60890 |
David S. Wishart | 108 | 523 | 76652 |
O. C. Zienkiewicz | 107 | 455 | 71204 |
Maciej Lewenstein | 104 | 931 | 47362 |
Jordi Rello | 103 | 694 | 35994 |
Anil Kumar | 99 | 2124 | 64825 |
Surendra P. Shah | 99 | 710 | 32832 |
Liang Wang | 98 | 1718 | 45600 |
Aharon Gedanken | 96 | 861 | 38974 |
María Vallet-Regí | 95 | 711 | 41641 |
Bonaventura Clotet | 94 | 784 | 39004 |
Roberto Elosua | 90 | 481 | 54019 |