Search results for "tiques"
showing 10 items of 1274 documents
Mapping Carbon Stocks In Central And South America With Smap Vegetation Optical Depth
2019
Mapping carbon stocks in the tropics is essential for climate change mitigation. Passive microwave remote sensing allows estimating carbon from deep canopy layers through the Vegetation Optical Depth (VOD) parameter. Although their spatial resolution is coarser than that of optical vegetation indices or airborne Lidar data, microwaves present a higher penetration capacity at low frequencies (L-band) and avoid cloud masking. This work compares the relationships of airborne carbon maps in Central and South America with both (i) SMAP L-band VOD at 9 km gridding and (ii) MODIS Enhanced Vegetation Index (EVI). Models to estimate carbon stocks are built from these two satellite-derived variables.…
Sensitivity of L-band vegetation optical depth to carbon stocks in tropical forests: a comparison to higher frequencies and optical indices
2019
Supplementary data to this article can be found online at https://doi.org/10.1016/j.rse.2019.111303. Monitoring vegetation carbon in tropical regions is essential to the global carbon assessment and to evaluate the actions oriented to the reduction of forest degradation. Mainly, satellite optical vegetation indices and LiDAR data have been used to this purpose. These two techniques are limited by cloud cover and are sensitive only to the top of vegetation. In addition, the vegetation attenuation to the soil microwave emission, represented by the vegetation optical depth (VOD), has been applied for biomass estimation using frequencies ranging from 4 to 30¿GHz (C- to K-bands). Atmosphere is t…
L-band vegetation optical depth seasonal metrics for crop yield assessment
2018
Attenuation of surface microwave emission due to the overlying vegetation is proportional to the density of the canopy and to its water content. The vegetation optical depth (VOD) parameter measures this attenuation. VOD could be a valuable source of information on agroecosystems, especially at lower frequencies for which greater portion of the vegetation canopy contributes to the observed brightness temperature. In the past, visible-infrared indices have been used to provide yield estimates based on measuring the photosynthetic activity from the surface canopy layer. These indices are affected by clouds and apply only in the presence of solar illumination. In this study we instead use the …
Isotropic-nematic interface in suspensions of hard rods: Mean-field properties and capillary waves
2006
We present a study of the isotropic-nematic interface in a system of hard spherocylinders. First we compare results from Monte Carlo simulations and Onsager density functional theory for the interfacial profiles of the orientational order parameter and the density. Those interfacial properties that are not affected by capillary waves are in good agreement, despite the fact that Onsager theory overestimates the coexistence densities. Then we show results of a Monte Carlo study of the capillary waves of the interface. In agreement with recent theoretical investigations (Eur.Phys.J. E {\bf 18} 407 (2005)) we find a strongly anistropic capillary wave spectrum. For the wave-numbers accessed in o…
Mid-infrared supercontinuum generation in chalcogenide and telluride fibers for sensor devices
2019
This thesis reports on the progress made during my PhD concerning supercontinuum generation and its application in two types of materials: chalcogenide and tellurite glasses. Concerning the chalcogenide axis, two new arsenic-free compositions are developed: Ge20Se60Te20 and Ge20Se70Te10. Thermal and optical properties of these two glasses are studied and two types of fibers are manufactured: a step-index fiber and a suspended core fiber. The generation of supercontinuum in these two fibres, pumped by an optical parametric amplifier, gives competitive results compared to the current state of the art of supercontinuum generation in chalcogenide fibres. Supercontinuums widening between 2 and 1…
Faire l'histoire des derniers ducs capétiens de Bourgogne (1272-1361) : sources, enjeux et méthodes
2018
International audience; La plupart des études portant sur les ducs de Bourgogne ont largement délaissé les Capétiens. L'objectif est d'envisager le gouvernement des quatre derniers ducs de cette dynastie - depuis Robert II (1272-1306) jusqu'à Philippe de Rouvres (1349-1361) - à partir de l'évolution des pratiques documentaires. En dressant un panorama des sources conservées à Dijon, notamment aux Archives Départementales de la Côte-d'Or, il s'agira de saisir les changements et les influences que connaissent les pratiques de gouvernement dans le champ de l'administration, de la comptabilité ou encore des archives
Mapa de la Península Ibérica
Publicat pel bàndol republicà. - Indicació de meridians i paral·lels formant quadrícula. - Relleu representat per tintes hipsomètriques i cotes d'altitud. - Relleu marí representat per isolínies i tintes hipsomètriques. - Llegenda indicant aeroports civils i militars, rutes aèries, bases d'hidroavions, passos aeris i zones d'exclusió aèria. - Representades divisions administratives, xarxes de carreteres i ferrocarrils, fars, ports i estacions meteorològiques Al cantó superior esquerre escut de l'aviació republicana durant la guerra civil
Plano de la Rada y Puerto de Alicante, H.286-A Mar Mediterráneo : Costa S.E de España
Escala expressada en milles. - Orientat amb rosa i fletxa indicant desviació magnètica. - Sondes. - Relleu en sombrejat. - Cultius representats. - Indica els fars pel color Inserta: Tabla de reducció de Metres a Braçes i Peus Primera correcció 1902, darrera 1960
Alicant
Gravat calcogràfic. - Orientat amb nus de 16 vents amb lis indicant el nord. - Relleu per ombrejat i muntanyes de perfil. - Batimetria per sondeig. - Ombrejat a la costa. - Representa la ciutat, el port, el castell i els seus voltants Al cantó superior dret: "Pl. 6"
Plano de la ensenada de Altea, H.288-A
Escala expressada també en milles. - Orientat amb rosa i fletxa indicant la variació magnètica. - Sondes. - Relleu per ombrejat. - Cultius i arbrats representats. - Fars indicats per color Primera correcció 1902 i darrera 1941 Sondes en metres. - Asenyalament del nord magnètic i geogràfic