Search results for "Design"
showing 10 items of 5885 documents
Rains of Solitons in a Fiber Laser
2009
We report a novel and intriguing nonlinear dynamics observed in a fiber laser cavity, in which soliton pulses are created from an extended noisy background and drift until they reach a condensed phase comprising several tens of aggregated solitons. This soliton flow can be adjusted with manual cavity tuning, and can even be triggered by the injection of an external low-power cw laser.
Analysis of the angular acceptance of surface plasmon Bragg mirrors
2007
International audience; We analyze an important aspect of the behavior of surface plasmon polariton (SPP) Bragg mirrors: the dependence of the angular acceptance for reflection on the incidence angle. By means of leakage radiation microscopy, both in direct and Fourier space, we observe that the angular acceptance diminishes for increasing incidence angles. This effect, which can considerably affect the design of devices based on these elements, is shown to be the consequence of the decrease of the bandgap width with increasing incidence angle. (c) 2007 Optical Society of America.
Dielectric-loaded plasmonic waveguide-ring resonators
2009
International audience; Using near-field microscopy, the performance of dielectric-loaded plasmonic waveguide-ring resonators (WRRs) operating at telecom wavelengths is investigated for various waveguide-ring separations. It is demonstrated that compact ( footprint similar to 150 mu m(2)) and efficient ( extinction ratio similar to 13 dB) WRR-based filters can be realized using UV-lithography. The WRR wavelength responses measured and calculated using the effective-index method are found in good agreement. (c) 2009 Optical Society of America
A near-field actuated optical nanocavity
2008
International audience; We demonstrate here that switching and tuning of a nanocavity resonance can be achieved by approaching a sub-micrometer tip inside its evanescent near-field. The resonance energy is tuned over a wide spectral range (Δλ/λ~10-3) without significant deterioration of the cavity peak-transmittance and of the resonance linewidth. Such a result is achieved by taking benefits from a weak tip-cavity interaction regime in which the tip behaves as a pure optical path length modulator.
Bend- and splitting loss of dielectric-loaded surface plasmon-polariton waveguides.
2008
International audience; The design, fabrication, characterization, and modeling of basic building blocks of plasmonic circuitry based on dielectric- loaded surface polariton waveguides, such as bends, splitters, and Mach- Zehnder interferometers are presented. The plasmonic components are realized by depositing subwavelength dielectric ridges on a smooth gold film using mass-production- compatible UV-photolithography. The near-field characterization at telecommunication wavelengths shows the strong mode confinement and low radiation and bend losses. The performance of the devices is found in good agreement with results obtained by full vectorial three-dimensional finite element simulations.…
Demonstration of a reef knot microfiber resonator.
2009
We propose a new way to realize a microfiber optical resonator by implementing the topology of a reef knot using two microfibers. We describe how this structure, which includes 4 ports and can serve as an add-drop filter, can be fabricated. Resonances in an all-silica reef knot are measured and good fits are obtained from a simple resonator model. We also show the feasibility of assembling a hybrid silica-chalcogenide reef knot structure.
Retour d’expériences sur le semis-direct sous couvert sans glyphosate
2019
Cet article présente les travaux menés dans le cadre du projet ENGAGED. Ce projet a été initié en 2016 à la demande d'agriculteurs normands qui pratiquent le Semis Direct sous Couvert Permanent de légumineuses pérenne (luzerne, trèfle) dans des rotations avec colza, blé, orge. Il vise à construire des systèmes de cultures basés sur la couverture permanente avec des Indicateurs de Fréquence de Traitements (IFT) herbicide inférieur à 1 sans avoir recours à l’utilisation du glyphosate. La faisabilité technique et les performances économiques des systèmes de cultures seront évaluées. La première phase de ce projet consiste à identifier les leviers existants pour gérer les adventices sous un cou…
Mixed Driven Refinement Design of Multidimensional Models based on Agglomerative Hierarchical Clustering
2015
20 pages; International audience; Data warehouses (DW) and OLAP systems are business intelligence technologies allowing the on-line analysis of huge volume of data according to users' needs. The success of DW projects essentially depends on the design phase where functional requirements meet data sources (mixed design methodology) (Phipps and Davis, 2002). However, when dealing with complex applications existing design methodologies seem inefficient since decision-makers define functional requirements that cannot be deduced from data sources (data driven approach) and/or they have not sufficient application domain knowledge (user driven approach) (Sautot et al., 2014b). Therefore, in this p…
Une méthodologie et un outil pour le prototypage rapide des entrepôts de données en utilisant le data mining : application à la biodiversité des oise…
2014
International audience; Data Warehouses (DWs) are large repositories of data aimed at supporting the decision-making process by enabling flexible and interactive analyses via OLAP systems. Rapid prototyping of DWs is necessary when OLAP applications are complex. Some work about the integration of Data Mining and OLAP systems has been done to enhance OLAP operators with mined indicators, and/or to define the DW schema. However, to best of our knowledge, prototyping methods for DWs do not support this kind of integration. Then, in this paper we present a new prototyping methodology for DWs, extending [3], where DM methods are used to define the DW schema. We validate our approach on a real da…
The role and management of crop-weed interactions in agroecological cropping systems
2020
International audience