23 research outputs found

    Application specific photonic integrated circuits through generic integration, a novel paradigm in photonics

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    [EN] This paper reviews our recent work on integrating photonic devices and sub-systems onto a single photonic chip, by means of generic integration.This work has been partially funded through the Spanish Plan Nacional de I+D+i 2008-2011 project ”Coupled Resonator Optical Waveguide eNgineering (CROWN)” grant no. TEC2008-06145/ TEC, by the Generalitat Valenciana through project PROMETEO/2008/092 and by the EC FP6 contract no. 004525 ePIXnet. J.D. Doménech acknowledges the FPI research grant BES-2009-018381.Muñoz Muñoz, P.; Doménech Gómez, JD.; Artundo Martínez, I.; Habib, C.; Leijtens, X.; De Vries, T.; Robbins, D.... (2011). Application specific photonic integrated circuits through generic integration, a novel paradigm in photonics. Waves. 3:58-64. http://hdl.handle.net/10251/57675S5864

    Broadband microwave photonic fully tunable filter using a single heterogeneously integrated III-V/SOI-microdisk-based phase shifter

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    This paper was published in OPTICS EXPRESS and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://dx.doi.org/10.1364/OE.20.010796. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under lawA broadband microwave photonic phase shifter based on a single III-V microdisk resonator heterogeneously integrated on and coupled to a nanophotonic silicon-on-insulator waveguide is reported. The phase shift tunability is accomplished by modifying the effective index through carrier injection. A comprehensive semi-analytical model aiming at predicting its behavior is formulated and confirmed by measurements. Quasi-linear and continuously tunable 2 pi phase shifts at radiofrequencies greater than 18 GHz are experimentally demonstrated. The phase shifter performance is also evaluated when used as a key element in tunable filtering schemes. Distortion-free and wideband filtering responses with a tuning range of similar to 100% over the free spectral range are obtained. (C) 2012 Optical Society of AmericaThe authors wish to acknowledge the technical support given by Rajesh Kumar and Pauline Mechet, as well as the financial support of the European Commission Seventh Framework Programme (FP 7) through the projects GOSPEL, WADIMOS and HISTORIC; the Generalitat Valenciana through the Microwave Photonics research Excellency award programme GVA PROMETEO 2008/092 and also the Plan Nacional I + D TEC2011-29120-C05-05 and TEC2008-06145.Lloret Soler, JA.; Morthier, G.; Ramos Pascual, F.; Sales Maicas, S.; Van Thourhout, D.; Spuesens, T.; Olivier, N.... (2012). Broadband microwave photonic fully tunable filter using a single heterogeneously integrated III-V/SOI-microdisk-based phase shifter. Optics Express. 20(10):10796-10806. doi:10.1364/OE.20.010796S1079610806201

    FIT Count Brasil: monitoramento de visitantes florais por contagem.

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    A Série de livros "Ciência Cidadã" tem como objetivo apresentar ao público diferentes questões científicas que podem ser trabalhadas com o auxílio de cientistas cidadãos e motivar diferentes pessoas (como você, por exemplo) a atuarem como cientistas cidadãos. No presente livro, apresentamos o protocolo intitulado "FIT COUNT: contagem cronometrada de visitantes florais"

    Africanized honey bees are efficient at detecting, uncapping and removing dead brood

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    The hygienic behavior of honey bees is based on a two-step process, including uncapping and removing diseased, dead, damaged, or parasitized brood inside the cell. We evaluated during periods of 1 h the time that hygienic and non-hygienic colonies of Africanized honey bees spend to detect, uncap and remove pin-killed brood using comb inserts with transparent walls placed in observation hives. We observed that hygienic colonies are significantly faster in detecting, uncapping and removing dead brood in the cells (P < 0.001).Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)CNPqFAPES

    Gender identification of five genera of stingless bees (Apidae, Meliponini) based on wing morphology

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    Currently, the identification of pollinators is a critical necessity of conservation programs. After it was found that features extracted from patterns of wing venation are sufficient to discriminate among insect species, various studies have focused on this structure. We examined wing venation patterns of males and workers of five stingless bee species in order to determine if there are differences between sexes and if these differences are greater within than between species. Geometric morphometric analyses were made of the forewings of males and workers of Nannotrigona testaceicornis, Melipona quadrifasciata, Frieseomelitta varia, and Scaptotrigona aff. depilis and Plebeia remota. The patterns of males and workers from the same species were more similar than the patterns of individuals of the same sex from different species, and the patterns of both males and workers, when analyzed alone, were sufficiently different to distinguish among these five species. This demonstrates that we can use this kind of analysis for the identification of stingless bee species and that the sex of the individual does not impede identification. Computer-assisted morphometric analysis of bee wing images can be a useful tool for biodiversity studies and conservation programs.Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)CNPq[151947/2007-4]FAPESP[04/15801-0]FAPESP[06/60615-5
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