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Genetic optimization of a vehicle fuzzy decision system for intersections

  • Onieva, Enrique
  • Milanés, Vicente
  • Villagrá, Jorge
  • Pérez Rastelli, Joshué Manuel
  • Godoy, Jorge
This paper presents a case study in which an autonomous vehicle must cooperate with a supposedly manually driven one to carry out a cross-roads manœuvre without risk. The main difference with other intersection systems is that the manual vehicle is driven without paying attention to the controlled one, so a cooperative coordination between vehicles is not possible. In this case is the autonomous vehicle the responsible of adapting its speed to the state of the manually driven, for finalizing the manœuvre both in a safe and efficient way. For this purpose, a three layer hierarchical fuzzy rule-based system (FRBS) is developed with the aim of dealing with such a situation: the first layer is in charge of detecting the kind of manœuvre that will be necessary; the second, in the case that an intersection is going to be crossed, is in charge of determining the suitable speed to do so without risk; and the third acts on the vehicle's real speed. The first two layers are implemented by means of fuzzy decision systems, with the second being optimized by a genetic algorithm (GA). The GA evaluates candidates in random simulated scenarios taking into account different factors to calculate the fitness. These factors are: implementing a free collision policy, avoiding unnecessary stops, and terminating the manœuvre as rapidly as possible. © 2012 Elsevier Ltd. All rights reserved., CYCIT (Spain); Plan Nacional (Spain) from the GUIADE, P9/08 ; TRANSIT, TRA2008-06602-C03-01, Peer Reviewed
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Search for Z′ resonances decaying to tt̄ in dilepton+jets final states in pp collisions at √s=7 TeV

  • Chatrchyan, S.
  • Brochero Cifuentes, J. A.
  • Cabrillo, I. J.
  • Calderon, Alicia
  • Chuang, S. H.
  • Duarte Campderros, J.
  • Felcini, Marta
  • Fernández, M.
  • Gómez, G.
  • González Sánchez, J.
  • Graziano, A.
  • Jorda, C.
  • López Virto, A.
  • Marco, Jesús
  • Marco, Rafael
  • Martínez-Rivero, Celso
  • Matorras, Francisco
  • Muñoz Sánchez, F. J.
  • Rodrigo, Teresa
  • Rodríguez Marrero, Ana Y.
  • Ruiz Jimeno, Alberto
  • Scodellaro, Luca
  • Vila, Iván
  • Vilar, Rocío
  • CMS Collaboration
A search for resonances decaying to top quark-antiquark pairs is performed using a dilepton+jets data sample recorded by the CMS experiment at the LHC in pp collisions at √s=7 TeV corresponding to an integrated luminosity of 5.0 fb-1. No significant deviations from the standard model background are observed. Upper limits are presented for the production cross section times branching fraction of top quark-antiquark resonances for masses from 750 to 3000 GeV. In particular, the existence of a leptophobic topcolor particle Z′ is excluded at the 95% confidence level for resonance masses MZ ′<1.3 TeV for ΓZ′=0.012MZ ′, and M<1.9 TeV for ΓZ′=0.10MZ ′. © 2013 CERN., We acknowledge support from BMWF and FWF (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, and FAPESP (Brazil); MEYS (Bulgaria); CERN; CAS, MoST, and NSFC (China); COLCIENCIAS (Colombia); MSES (Croatia); RPF (Cyprus); MoER, SF0690030s09 and ERDF (Estonia); Academy of Finland, MEC, and HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG, and HGF (Germany); GSRT (Greece); OTKA and NKTH (Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); NRF and WCU (Korea); LAS (Lithuania); CINVESTAV, CONACYT, SEP, and UASLPFAI (Mexico); MSI (New Zealand); PAEC (Pakistan); MSHE and NSC (Poland); FCT (Portugal); JINR (Armenia, Belarus, Georgia, Ukraine Uzbekistan); MON, RosAtom, RAS and RFBR (Russia); MSTD (Serbia); SEIDI and CPAN (Spain); Swiss Funding Agencies (Switzerland); NSC (Taipei); ThEP, IPST and NECTEC (Thailand); TUBITAK and TAEK (Turkey); NASU (Ukraine); STFC (United Kingdom); DOE and NSF (USA)., Peer Reviewed
Proyecto:


Search for the standard model Higgs boson produced in association with a top-quark pair in pp collisions at the LHC

  • Chatrchyan, S.
  • Brochero Cifuentes, J. A.
  • Cabrillo, I. J.
  • Calderon, Alicia
  • Chuang, S. H.
  • Duarte Campderros, J.
  • Fernández, M.
  • Gómez, G.
  • González Sánchez, J.
  • Graziano, A.
  • Jorda, C.
  • López Virto, A.
  • Marco, Jesús
  • Marco, Rafael
  • Martínez-Rivero, Celso
  • Matorras, Francisco
  • Muñoz Sánchez, F. J.
  • Rodrigo, Teresa
  • Rodríguez Marrero, Ana Y.
  • Ruiz Jimeno, Alberto
  • Scodellaro, Luca
  • Vila, Iván
  • Vilar, Rocío
  • CMS Collaboration
Open Access: This article is distributed under the terms of the Creative Commons Attribution License.-- et al., A search for the standard model Higgs boson produced in association with a top-quark pair is presented using data samples corresponding to an integrated luminosity of 5.0 fb-1 (5.1 fb-1) collected in pp collisions at the center-of-mass energy of 7 TeV (8 TeV). Events are considered where the top-quark pair decays to either one lepton+jets (tt̄ → ℓvqq̄bb̄) or dileptons (tt̄ → ℓ+vl- rfvn1̄bb̄), ℓ being an electron or a muon. The search is optimized for the decay mode H → bb̄. The largest background to the tt̄H signal is top-quark pair production with additional jets. Artificial neural networks are used to discriminate between signal and background events. Combining the results from the 7 TeV and 8 TeV samples, the observed (expected) limit on the cross section for Higgs boson production in association with top-quark pairs for a Higgs boson mass of 125 GeV is 5.8 (5.2) times the standard model expectation., We acknowledge support from BMWF and FWF (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, and FAPESP (Brazil); MEYS (Bulgaria); CERN; CAS, MoST, and NSFC (China); COLCIENCIAS (Colombia); MSES (Croatia); RPF (Cyprus); MoER, SF0690030s09 and ERDF (Estonia); Academy of Finland, MEC, and HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG, and HGF (Germany); GSRT (Greece); OTKA and NKTH (Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); NRF and WCU (Korea); LAS (Lithuania); CINVESTAV, CONACYT, SEP, and UASLPFAI (Mexico); MSI (New Zealand); PAEC (Pakistan); MSHE and NSC (Poland); FCT (Portugal); JINR (Armenia, Belarus, Georgia, Ukraine Uzbekistan); MON, RosAtom, RAS and RFBR (Russia); MSTD (Serbia); SEIDI and CPAN (Spain); Swiss Funding Agencies (Switzerland); NSC (Taipei); ThEP, IPST and NECTEC (Thailand); TUBITAK and TAEK (Turkey); NASU (Ukraine); STFC (United Kingdom); DOE and NSF (USA). Individuals have received support from the Marie-Curie programme and the European Research Council and EPLANET(EuropeanUnion); the Leventis Foundation; the A.P. Sloan Foundation; the Alexander von Humboldt Foundation; the Belgian Federal Science Policy Office; the Fonds pour la Formation à la Recherche dans l’Industrie et dansl’Agriculture (FRIA-Belgium); the Agentschap voor Innovatie door Wetenschapen Technologie (IWT-Belgium); the Ministry of Education, Youth and Sports(MEYS) of Czech Republic; the Council of Science and Industrial Research, India; the Compagnia di San Paolo(Torino); the HOMINGPLUS programme of Foundation for PolishScience, cofinanced by EU,Re-gional Development Fund; and the Thalis and Aristeia programmes cofinanced byEU-ESFand the Greek NSRF., Peer Reviewed
Proyecto:


Search for supersymmetry in hadronic final states with missing transverse energy using the variables αT and b-quark multiplicity in pp collisions at √s=8 TeV

  • Chatrchyan, S.
  • Brochero Cifuentes, J. A.
  • Cabrillo, I. J.
  • Calderon, Alicia
  • Chuang, S. H.
  • Duarte Campderros, J.
  • Fernández, M.
  • Gómez, G.
  • González Sánchez, J.
  • Graziano, A.
  • Jorda, C.
  • López Virto, A.
  • Marco, Jesús
  • Marco, Rafael
  • Martínez-Rivero, Celso
  • Matorras, Francisco
  • Muñoz Sánchez, F. J.
  • Rodrigo, Teresa
  • Rodríguez Marrero, Ana Y.
  • Ruiz Jimeno, Alberto
  • Scodellaro, Luca
  • Vila, Iván
  • Vilar, Rocío
  • CMS Collaboration
Open Access: This article is distributed under the terms of the Creative Commons Attribution License.-- et al., An inclusive search for supersymmetric processes that produce final states with jets and missing transverse energy is performed in pp collisions at a centre-of-mass energy of 8 TeV. The data sample corresponds to an integrated luminosity of 11.7 fb−1 collected by the CMS experiment at the LHC. In this search, a dimensionless kinematic variable, α T, is used to discriminate between events with genuine and misreconstructed missing transverse energy. The search is based on an examination of the number of reconstructed jets per event, the scalar sum of transverse energies of these jets, and the number of these jets identified as originating from bottom quarks. No significant excess of events over the standard model expectation is found. Exclusion limits are set in the parameter space of simplified models, with a special emphasis on both compressed-spectrum scenarios and direct or gluino-induced production of third-generation squarks. For the case of gluino-mediated squark production, gluino masses up to 950–1125 GeV are excluded depending on the assumed model. For the direct pair-production of squarks, masses up to 450 GeV are excluded for a single light first- or second-generation squark, increasing to 600 GeV for bottom squarks., We acknowledge the enduring support for the construction and operation of the LHC and the CMS detector provided by the following funding agencies: the Austrian Federal Ministry of Science and Research; the Belgian Fonds de la Recherche Scientifique, and Fonds voor Wetenschappelijk Onderzoek; the Brazilian Funding Agencies (CNPq, CAPES, FAPERJ, and FAPESP); the Bulgarian Ministry of Education, Youth and Science; CERN; the Chinese Academy of Sciences, Ministry of Science and Technology, and National Natural Science Foundation of China; the Colombian Funding Agency (COLCIENCIAS); the Croatian Ministry of Science, Education and Sport; the Research Promotion Foundation, Cyprus; the Ministry of Education and Research, Recurrent financing contract SF0690030s09 and European Regional Development Fund, Estonia; the Academy of Finland, Finnish Ministry of Education and Culture, and Helsinki Institute of Physics; the Institut National de Physique Nucle´aire et de Physique des Particules/CNRS, and Commissariat à l’Énergie Atomique et aux E'nergies Alternatives/CEA, France; the Bundesministerium für Bildung und Forschung, Deutsche Forschungsgemeinschaft, and Helmholtz-Gemeinschaft Deutscher Forschungszentren, Germany; the General Secretariat for Research and Technology, Greece; the National Scientific Research Foundation, and National Office for Research and Technology, Hungary; the Department of Atomic Energy and the Department of Science and Technology, India; the Institute for Studies in Theoretical Physics and Mathematics, Iran; the Science Foundation, Ireland; the Istituto Nazionale di Fisica Nucleare, Italy; the Korean Ministry of Education, Science and Technology and the World Class University program of NRF, Republic of Korea; the Lithuanian Academy of Sciences; the Mexican Funding Agencies (CINVESTAV, CONACYT, SEP, and UASLP-FAI); the Ministry of Science and Innovation, New Zealand; the Pakistan Atomic Energy Commission; the Ministry of Science and Higher Education and the National Science Centre, Poland; the Fundaçao para a Ciência e a Tecnologia, Portugal; JINR (Armenia, Belarus, Georgia, Ukraine, Uzbekistan); the Ministry of Education and Science of the Russian Federation, the Federal Agency of Atomic Energy of the Russian Federation, Russian Academy of Sciences, and the Russian Foundation for Basic Research; the Ministry of Science and Technological Development of Serbia; the Secretaría de Estado de Investigación, Desarrollo e Innovación and Programa Consolider-Ingenio 2010, Spain; the Swiss Funding Agencies (ETH Board, ETH Zurich, PSI, SNF, UniZH, Canton Zurich, and SER); the National Science Council, Taipei; the Thailand Center of Excellence in Physics, the Institute for the Promotion of Teaching Science and Technology of Thailand and the National Science and Technology Development Agency of Thailand; the Scientific and Technical Research Council of Turkey, and Turkish Atomic Energy Authority; the Science and Technology Facilities Council, U.K.; the U.S. Department of Energy, and the U.S. National Science Foundation. Individuals have received support from the Marie-Curie program and the European Research Council (European Union); the Leventis Foundation; the A. P. Sloan Foundation; the Alexander von Humboldt Foundation; the Belgian Federal Science Policy Office; the Fonds pour la Formation à la Recherche dans l’Industrie et dans l’Agriculture (FRIA-Belgium); the Agentschap voor Innovatie door Wetenschap en Technologie (IWT-Belgium); the Ministry of Education, Youth and Sports (MEYS) of Czech Republic; the Council of Science and Industrial Research, India; the Compagnia di San Paolo (Torino); and the HOMING PLUS program of Foundation for Polish Science, cofinanced from European Union, Regional Development Fund., Peer Reviewed
Proyecto:


Les conversions d'Européens à l'islam dans l'histoire: esquisse générale

  • García-Arenal, Mercedes
The author discusses the conversion to Islam of Europeans living in or moving to Islamic countries between the 16th and the first half of the 20th century. Taking a historical viewpoint, she highlights continuities and differences which could be of use in the analysis of the present-day situation. She distinguishes between the conversion of whole communities and that of individuals, and finds that identity and culture are more common motives for conversion than strictly religious reasons., Peer reviewed
Proyecto:


Search for supersymmetry in pp collisions at √s=7 TeV in events with a single lepton, jets, and missing transverse momentum

  • Chatrchyan, S.
  • Brochero Cifuentes, J. A.
  • Cabrillo, I. J.
  • Calderon, Alicia
  • Chuang, S. H.
  • Duarte Campderros, J.
  • Felcini, Marta
  • Fernández, M.
  • Gómez, G.
  • González Sánchez, J.
  • Graziano, A.
  • Jorda, C.
  • López Virto, A.
  • Marco, Jesús
  • Marco, Rafael
  • Martínez-Rivero, Celso
  • Martínez-Rivero, Celso
  • Matorras, Francisco
  • Muñoz Sánchez, F. J.
  • Rodrigo, Teresa
  • Rodríguez Marrero, Ana Y.
  • Ruiz Jimeno, Alberto
  • Scodellaro, Luca
  • Vila, Iván
  • Vilar, Rocío
  • CMS Collaboration
Open Access: This article is distributed under the terms of the Creative Commons Attribution License.-- et al., Results are reported from a search for new physics processes in events containing a single isolated high-transverse-momentum lepton (electron or muon), energetic jets, and large missing transverse momentum. The analysis is based on a 4.98 fb−1 sample of proton–proton collisions at a center-of-mass energy of 7 TeV, obtained with the CMS detector at the LHC. Three separate background estimation methods, each relying primarily on control samples in the data, are applied to a range of signal regions, providing complementary approaches for estimating the background yields. The observed yields are consistent with the predicted standard model backgrounds. The results are interpreted in terms of limits on the parameter space for the constrained minimal supersymmetric extension of the standard model, as well as on cross sections for simplified models, which provide a generic description of the production and decay of new particles in specific, topology based final states., We acknowledge support from BMWF and FWF (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, and FAPESP (Brazil); MEYS (Bulgaria); CERN; CAS, MoST, and NSFC (China); COLCIENCIAS (Colombia); MSES (Croatia); RPF (Cyprus); MoER, SF0690030s09 and ERDF (Estonia); Academy of Finland, MEC, and HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG, and HGF (Germany); GSRT (Greece); OTKA and NKTH (Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); NRF and WCU (Korea); LAS (Lithuania); CINVESTAV, CONACYT, SEP, and UASLPFAI (Mexico); MSI (New Zealand); PAEC (Pakistan); MSHE and NSC (Poland); FCT (Portugal); JINR (Armenia, Belarus, Georgia, Ukraine Uzbekistan); MON, RosAtom, RAS and RFBR (Russia); MSTD (Serbia); SEIDI and CPAN (Spain); Swiss Funding Agencies (Switzerland); NSC (Taipei); ThEP, IPST and NECTEC (Thailand); TUBITAK and TAEK (Turkey); NASU (Ukraine); STFC (United Kingdom); DOE and NSF (USA). Individuals have received support from the Marie-Curie programme and the European Research Council and EPLANET(EuropeanUnion); the Leventis Foundation; the A.P. Sloan Foundation; the Alexander von Humboldt Foundation; the Belgian Federal Science Policy Office; the Fonds pour la Formation à la Recherche dans l’Industrie et dansl’Agriculture (FRIA-Belgium); the Agentschap voor Innovatie door Wetenschapen Technologie (IWT-Belgium); the Ministry of Education, Youth and Sports(MEYS) of Czech Republic; the Council of Science and Industrial Research, India; the Compagnia di San Paolo(Torino); the HOMINGPLUS programme of Foundation for PolishScience, cofinanced by EU,Re-gional Development Fund; and the Thalis and Aristeia programmes cofinanced byEU-ESFand the Greek NSRF., Peer Reviewed
Proyecto:


Exposure of snail Hydrobia ulvae to copper spiked estuarine sediment: effects on activity and postexposure feeding

  • Araújo, Cristiano V. M.
  • Blasco, Julián
  • Moreno-Garrido, Ignacio
Trabajo presentado en el XII Congresso Brasileiro de Ecotoxicologia. celebrado en Porto de Galihnas (Brasil) del 25 al 28 de septiembre de 2012., The response of snail Hydrobia ulvae (gastropod) exposed to copper spiked sediment sample has been assessed using two different endpoints: activity and postexposure feeding (indirectly measured as faecal pellets produced). Two main goals were addressed: (i) how H. ulvae activity (crawling) is hampered due to copper exposure via sediment, and (ii) how postexposure feeding is affected after the exposure has been stopped. Initially, organisms were directly exposed to copper spiked sediment samples (0, 20, 80, 200, 400 and 800 ¿g Cu g-1) for 96 h and at the end readings about activity were recorded. Feeding was recorded in a postexposure experiment in water after exposure to spiked sediment. For this last propose, organisms were fed for 24 h and afterwards the feeding was stopped and the faecal pellets produced during the next 3 h were counted. Results attest that activity was roughly influenced by presence of copper in sediment. At the two highest concentrations (400 and 800 ¿g Cu g-1) the activity was respectively 53 and 67% lower (p<0.05) than the reference sample. The 96 h-EC50 for activity was of 451 (407-499) ¿g Cu g-1. Inhibition on feeding (total pellets) reached 54 and 78% at 200 and 400 ¿g Cu g-1, respectively; however, at 800 ¿g Cu g-1 the effect was not so pronounced (inhibition of 38%). The 24 h-EC50 for postexposure feeding was of 190 (±35) ¿g Cu g-1 taking into account the highest concentration and 181 (±10) ¿g Cu g-1 when the highest concentration was not considered. Special attention should be given to the role of sediment as food source in experiment with sediment where postexposure feeding is used as response. At concentration as high as 800 ¿g Cu g-1, the high rate of inactivity may have led the organisms to starvation for 96 h; which seems to have been later recovered in the postexposure experiments and a higher number of pellets was produced. These results showed clearly that the crawling activity of H. ulvae is inhibited due to presence of copper in sediment; however, the experiments of postexposure feeding as response to previous exposure to sediment should consider its role as food source and consequently potential confounding factor., Peer Reviewed
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Graphdiyne Pores: “Ad Hoc” Openings for Helium Separation Applications

  • Bartolomei, Massimiliano
  • Carmona-Novillo, Estela
  • Hernández, Marta I.
  • Campos-Martínez, José
  • Pirani, Fernando
  • Giorgi, Giacomo
7 pags.; 4 figs. ;*S Supporting Information Periodic DFT calculations as well as intermolecular potentials related to different configurations used for graphdiyne pore−methane computations. This material is available free of charge via the Internet at http://pubs.acs.org., Two-dimensional (2D) materials deriving from graphene, such as graphdiyne and 2D polyphenylene honeycomb (2DPPH), have been recently synthesized and exhibit uniformly distributed subnanometer pores, a feature that can be exploited for gas filtration applications. Accurate first-principles electronic structure calculations are reported showing that graphdiyne pores permit an almost unimpeded helium transport while it is much more difficult through the 2DPPH openings. Quantum dynamical simulations on reliable new force fields are performed in order to assess the graphdiyne capability for helium chemical and isotopic separation. Exceptionally high He/CH4 selectivities are found in a wide range of temperatures which largely exceed the performance of the best membranes used to date for helium extraction from natural gas. Moreover, due to slight differences in the tunneling probabilities of 3He and 4He, we also find promising results for the separation of the Fermionic isotope at low temperature. © 2014 American Chemical Society, The work has been funded by Spanish Grants FIS2010-22064-C02-02 and FIS2013-48275-C2-1-P. Allocation of computing time by CESGA (Spain) is also acknowledged. F.P. acknowledges financial support from the Italian Ministry of University and Research (MIUR) for PRIN 2010-2011, Grant 2010 ERFKXL_002., Peer reviewed
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Catalytic acetoxylation of lactic acid to 2-acetoxypropionic acid, en route to acrylic acid

  • Beerthuis, Rolf
  • Granollers, Marta
  • Brown, D. Robert
  • Salavagione, Horacio J.
  • Rothenberg, Gadi
  • Shiju, N. Raveendran
We present an alternative synthetic route to acrylic acid, starting from the platform chemical lactic acid and using heterogeneous catalysis. To improve selectivity, we designed an indirect dehydration reaction that proceeds via acetoxylation of lactic acid to 2-acetoxypropionic acid. This intermediate can then be pyrolized to acrylic acid. Acetic acid is used both as a reagent and a solvent in the first step, and may be recovered in the subsequent pyrolysis step. We tested a range of solid acid catalysts for the acetoxylation step (Y zeolites, sulfated zirconia, ion-exchange resins, sulfonated graphene, and various sulfonated silica gels and mixed oxides). Recycling studies were carried out for the most active catalysts. To enable quantitative analysis using gas chromatography we also developed a reliable silylation derivatization method, which is also reported. These results open opportunities for improving the biorenewable production of acrylic acid., Peer Reviewed
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