Search results for "Planet"
showing 10 items of 5662 documents
Análisis de métodos de validación cruzada para la obtención robusta de parámetros biofísicos
2015
[EN] Non-parametric regression methods are powerful statistical methods to retrieve biophysical parameters from remote sensing measurements. However, their performance can be affected by what has been presented during the training phase. To ensure robust retrievals, various cross-validation sub-sampling methods are often used, which allow to evaluate the model with subsets of the field dataset. Here, two types of cross-validation techniques were analyzed in the development of non-parametric regression models: hold-out and k-fold. Selected non-parametric linear regression methods were least squares Linear Regression (LR) and Partial Least Squares Regression (PLSR), and nonlinear methods were…
A New Algorithm for the Retrieval of Sun Induced Chlorophyll Fluorescence of Water Bodies Exploiting the Detailed Spectral Shape of Water-Leaving Rad…
2021
Sun induced chlorophyll fluorescence (SICF) emitted by phytoplankton provides considerable insights into the vital role of the carbon productivity of the earth’s aquatic ecosystems. However, the SICF signal leaving a water body is highly affected by the high spectral variability of its optically active constituents. To disentangle the SICF emission from the water-leaving radiance, a new high spectral resolution retrieval algorithm is presented, which significantly improves the fluorescence line height (FLH) method commonly used so far. The proposed algorithm retrieves the reflectance without SICF contribution by the extrapolation of the reflectance from the adjacent regions. Then, the SICF …
Radio Insight into the Nature of Type IIb Progenitors
2011
AbstractWe present the results of over two decades of radio observations of type IIb Supernovae with the Very Large Array and the Australia Telescope Compact Array. These radio studies illustrate the need for multi-wavelength follow-up to determine the progenitor scenario for type IIb events.
On the Variability of the Temperature Coefficients of mc-Si Solar Cells with Irradiance
2016
Abstract The temperature sensitivity of silicon solar cells is in general assumed to be constant with irradiance in PV forecasting models, although it has been demonstrated experimentally that this is not true. In this study a theoretical model is established that describes the variation of the temperature coefficients of a silicon solar cell as a function of the irradiance. It is shown that the temperature sensitivity of the solar cell efficiency is decreasing with the irradiance and that the main reason for this behavior comes from the increase of the open-circuit voltage with light intensity. Moreover, a dependency of the cell's ideality factor on the irradiance has to be assumed to rece…
Una aproximació intrasubjecte a la teoria prospectiva
2018
espanolEn el presente estudio hemos retomado la investigacion llevada a cabo por Kahneman y Tversky (1979) que dio origen a su Teoria Prospectiva. La importancia de esta teoria radica, por un lado, en la critica que supuso a la teoria de la utilidad esperada y, por otro lado, a que permitio la formulacion del efecto de certidumbre –o certeza–, de reflexion y del efecto marco. Estos autores utilizaron en sus estudios generalmente disenos experimentales intra-sujeto. Nuestro objetivo ha consistido en comprobar si los efectos encontrados por estos autores se mantienen igualmente a pesar de llevar a cabo un ana- lisis intra-sujeto, estableciendo como hipotesis que sus planteamientos no serian r…
A comparison of Microtops II and satellite ozone measurements in the period 2001-2011
2013
Daily average total ozone Microtops measurements obtained during several campaigns conducted from 2001 to 2011 at latitudes from 31 to 68N and in different seasons are compared with satellite observations. The Microtops ozone is derived using different wavelength combinations (Channel I, 305.5/312.5. nm; Channel II, 312.5/320. nm; and Channel III, 305.5/312.5/320. nm). Satellite data from TOMS, OMI, GOME, and GOME-2 are used in the comparison. The three Microtops channels show a high correlation with the satellite retrievals. Channel I shows the best results and produces a mean bias deviation (MBD) less than 2.14% with respect to TOMS, OMI and GOME. The MBD increases to 3% in the comparison…
Range-based versus automated markerless image-based techniques for rock art documentation
2014
Nowadays there is a huge proliferation of fully automatic image-based solutions producing either three-dimensional (3D) point clouds or 3D models. However, the reliability of the output is not usually reported and clarified. This paper presents a comparison of the 3D modelling results achieved on two rock art shelters at separate archaeological sites using a high-resolution digital camera. The 3D point clouds were produced using automatic image-based photogrammetric and computer vision software running either locally (FOTOGIFLE and VisualSFM) or through a webbased reconstruction service (Autodesk 123D Catch). The first two automatic approaches are compared with a manual bundle block adjustm…
Reviving the EU project: from values to new territorial development models
2020
Le but de cet article est d’analyser les relations entre l'aménagement du territoire, la cohésion territoriale (comme but à atteindre et comme politique) et les valeurs qui sous-tendent le projet de l'Union européenne (UE). Les territoires, les cultures et l’histoire des pays de l'UE peuvent jouer un rôle afin de redéfinir l'UE comme modèle social et politique de référence à l'échelle mondiale. Dans la « nouvelle grande transition » (écologique, économique, sociale, urbaine, féministe, démocratique…), la dimension territoriale et les politiques publiques jouent un rôle clé dans la définition des futurs possibles : nouveau modèle de développement économique, nouveaux modèles spatiaux et nouv…
Thermal Analysis of the Solar Orbiter PHI Electronics Unit
2020
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La Seconda Vita dell'Ambiente Costruito
2021
Il contributo inquadra i saggi, gli studi, le ricerche e progetti pubblicati sul numero 9 di AGATHÓN su ‘La Seconda Vita dell’Ambiente Costruito’, tema di interesse per il mondo accademico, delle professioni e dell’industria. Cambiamenti climatici, eccessivo consumo di suolo e di risorse non rinnovabili, produzione sempre crescente di rifiuti, emergenza pandemica e crisi socio-economica globale sono entrati di fatto nel nostro quotidiano: seppur drammatiche, per certi versi, tali questioni possono essere colte come un’opportunità per ripensare il modo e il mondo in cui viviamo. In questo contesto di ‘rivoluzione’(Floridi, 2020) e di ‘policrisi’ (Losasso, 2020), e con riferimento specifico a…