Search results for "Optical image"

showing 4 items of 4 documents

Classifying Major Explosions and Paroxysms at Stromboli Volcano (Italy) from Space

2021

Stromboli volcano has a persistent activity that is almost exclusively explosive. Predominated by low intensity events, this activity is occasionally interspersed with more powerful episodes, known as major explosions and paroxysms, which represent the main hazards for the inhabitants of the island. Here, we propose a machine learning approach to distinguish between paroxysms and major explosions by using satellite-derived measurements. We investigated the high energy explosive events occurring in the period January 2018–April 2021. Three distinguishing features are taken into account, namely (i) the temporal variations of surface temperature over the summit area, (ii) the magnitude of the …

High energygeographygeography.geographical_feature_categorysatellite remote sensingExplosive materialLand surface temperaturemachine learning classifierScienceQPlume heightoptical imageryMagnitude (mathematics)volcanic explosionsPlumeVolcanoGeneral Earth and Planetary Sciencesradar imageryvolcanic explosions; satellite remote sensing; machine learning classifier; optical imagery; radar imagerySeismologyGeologyVolcanic ashRemote Sensing
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Single cigar-shaped nanopores functionalized with amphoteric amino acid chains: experimental and theoretical characterization.

2012

We present an experimental and theoretical characterization of single cigar-shaped nanopores with pH-responsive carboxylic acid and lysine chains functionalized on the pore surface. The nanopore characterization includes (i) optical images of the nanostructure obtained by FESEM; (ii) different chemical procedures for the nanopore preparation (etching time and functionalizations; pH and electrolyte concentration of the external solution) allowing externally tunable nanopore responses monitored by the current-voltage (I-V) curves; and (iii) transport simulations obtained with a multilayer nanopore model. We show that a single, approximately symmetric nanopore can be operated as a reconfigurab…

NanoporeRe-configurablePHAmino acid chainsEtching timeElectrical signalCarboxylic AcidsGeneral Physics and AstronomyFunctionalizationsElectrolytePore surfaceElectrochemistryFunctionalizedCarboxylic acidOptical imageNanoporesElectric conductivityI - V curveElectrochemistryGeneral Materials ScienceTheoretical modelRectifying behaviorsFundamental conceptsRectifying propertiesSurface propertyGeneral EngineeringHydrogen-Ion ConcentrationCigar-shaped nanoporeCharacterization (materials science)Data processingChemistryNanoporeAmino acidsIon channelTransport simulationIodineLogic functionsNanostructureMaterials scienceLogicSurface PropertiesCharacterizationNanotechnologyTunabilitiesArticleDrug controlled releaseElectrical resistivity and conductivityEtchingTransport processPH-responsiveCurrent voltage curveDiodeChemical proceduresCarboxylic acidsLysineElectric ConductivityModels TheoreticalGeometrical opticsNanostructuresAmphoteric amino acid chainsCurrent-voltage curvesExternal solutionsFISICA APLICADAElectrolyte concentrationACS nano
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Contribution à l'étude de la formation des images optiques en microscopie champ proche optique: effet de la sonde en deux dimensions

2004

This work consists in the development of a theoretical tool for the purpose to undertake numerical simulations able to take into account the coupling between the probe and the object. The first part, concerns the combination of the differential method and the algorithms T and S, to overcome numerical problems which appear in the cases where the size of system (probe - object) is more realistic. The developed global model is two-dimensional and applied in polarization TE under the normal diffraction condition. We have used the developed model to study the formation of optical image by monomodes and multimodes probes. The obtained optical images at constant height, have allowed us to study th…

Optique de champ prochePhotonic Scanning Tunnelling Microscopy ( PSTM)Near-field opticImages optiquesMéthode différentielle et Algorithmes matricielsmatrix algorithmsprobe-object couplingCouplage sonde-objetOptical imagesOptical ProbeMéthode différentielle et Algorithmes matriciels.[PHYS.PHYS] Physics [physics]/Physics [physics]differential methodMicroscope à effet Tunnel Photonique (PSTM)
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Observation of Light Confinement Effects with a Near-Field Optical Microscope.

1996

This Letter reports the experimental observation of light confinement effects by near-field optical microscopy. Depolarization effects giving rise to light confinement close to nanoscopic objects have been unambiguously observed in near-field optical images of subwavelength dielectric pads etched on a flat glass substrate. According to the incident polarization, this phenomenon leads to reverse contrasts in the near-field optical image of the same subwavelength objects.

Optical imageMaterials sciencegenetic structuresbusiness.industryNear-field opticsPhysics::OpticsGeneral Physics and AstronomyDielectricFlat glassPolarization (waves)law.inventionOpticsOptical microscopelawOptoelectronicsNear field optical microscopebusinessNanoscopic scalePhysical review letters
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