Search results for "Planetary Science"
showing 10 items of 4367 documents
Synergy of Sentinel-1 and Sentinel-2 Time Series for Cloud-Free Vegetation Water Content Mapping with Multi-Output Gaussian Processes
2023
Optical Earth Observation is often limited by weather conditions such as cloudiness. Radar sensors have the potential to overcome these limitations, however, due to the complex radar-surface interaction, the retrieving of crop biophysical variables using this technology remains an open challenge. Aiming to simultaneously benefit from the optical domain background and the all-weather imagery provided by radar systems, we propose a data fusion approach focused on the cross-correlation between radar and optical data streams. To do so, we analyzed several multiple-output Gaussian processes (MOGP) models and their ability to fuse efficiently Sentinel-1 (S1) Radar Vegetation Index (RVI) and Senti…
Prevalencia y factores de desgaste profesional en radiólogos durante la pandemia COVID-19
2022
Antecedentes: La epidemia por coronavirus 2019 (COVID-19) se ha extendido por todo el mundo desde principios de 2020, sometiendo a los profesionales sanitarios a una sobrecarga laboral ya un mayor nivel de estrés físico y emocional. Objetivos: El objetivo de este estudio es determinar la prevalencia de desgaste profesional y sus posibles factores asociados en los radiólogos españoles durante la COVID-19, y su comparación con la situación previa a la pandemia. Métodos: Estudio observacional realizado entre los meses de abril y agosto de 2020 (durante la pandemia) mediante una encuesta en línea. Se obtuvieron un total de 150 respuestas. Se recopiló y comparó la información demográfica y labor…
Global Estimation of Biophysical Variables from Google Earth Engine Platform
2018
This paper proposes a processing chain for the derivation of global Leaf Area Index (LAI), Fraction of Absorbed Photosynthetically Active Radiation (FAPAR), Fraction Vegetation Cover (FVC), and Canopy water content (CWC) maps from 15-years of MODIS data exploiting the capabilities of the Google Earth Engine (GEE) cloud platform. The retrieval chain is based on a hybrid method inverting the PROSAIL radiative transfer model (RTM) with Random forests (RF) regression. A major feature of this work is the implementation of a retrieval chain exploiting the GEE capabilities using global and climate data records (CDR) of both MODIS surface reflectance and LAI/FAPAR datasets allowing the global estim…
Biological and Mechanical Characterization of the Random Positioning Machine (RPM) for Microgravity Simulations
2021
The rapid improvement of space technologies is leading to the continuous increase of space missions that will soon bring humans back to the Moon and, in the coming future, toward longer interplanetary missions such as the one to Mars. The idea of living in space is charming and fascinating; however, the space environment is a harsh place to host human life and exposes the crew to many physical challenges. The absence of gravity experienced in space affects many aspects of human biology and can be reproduced in vitro with the help of microgravity simulators. Simulated microgravity (s-μg) is applied in many fields of research, ranging from cell biology to physics, including cancer biology. In…
Més enllà de Kohlberg: l'aprenentatge ètic per a la coherència entre judici, sentiments i accions morals
2017
espanolPara la comunidad educativa el desarrollo moral sigue siendo un asunto de preocupacion. Varios agentes educativos dedican tiempo y esfuerzo a un tema que, actualmente, evidencia una clara separacion entre lo teorico y lo practico, un sesgo entre lo que uno piensa y lo que uno hace, entre el razonamiento y las acciones morales. Las finalidades y las intenciones de los agentes educativos son respetables; pero contrariamente a estas, ninos y adolescentes actuan de manera demasiado reactiva y les cuesta generalizar ciertos comportamientos. En esta linea, el planteamiento de Kohlberg, centrado en el desarrollo del juicio y el razonamiento moral, parece proporcionarles principalmente eleme…
TISSBERT: A benchmark for the validation and comparison of NDVI time series reconstruction methods
2018
[EN] This paper introduces the Time Series Simulation for Benchmarking of Reconstruction Techniques (TISSBERT) dataset, intended to provide a benchmark for the validation and comparison of time series reconstruction methods. Such methods are routinely used to estimate vegetation characteristics from optical remotely sensed data, where the presence of clouds decreases the usefulness of the data. As for their validation, these methods have been compared with previously published ones, although with different approaches, which sometimes lead to contradictory results. We designed the TISSBERT dataset to be generic so that it could simulate realistic reference and cloud-contaminated time series …
S’aimer à l’heure du numérique : la relation conjugale à l’épreuve de l’hyperconnectivité
2014
L’introduction des nouveaux objets connectés (NOC) dans les foyers vient réinterroger la relation conjugale. Avec les objets nomades, le couple doit faire face à un individualisme connecté. Ils amplifient notamment la privatisation des territoires dans l’espace domestique semblant de ce fait affecter la conversation conjugale. À travers notre enquête, nous avons constaté que les technologies de l’information et de la communication (TIC) peuvent certes avoir un impact négatif sur la relation de couple, mais peuvent a contrario venir renforcer la relation en donnant entre autres une nouvelle place à l’écrit dans la communication conjugale. Des différences apparaissent toutefois selon les type…
Rotational effects on the oscillation frequencies of newly born proto-neutron stars
2003
In this paper we study the effects of rotation on the frequencies of the quasi-normal modes of a proto-neutron star (PNS) born in a gravitational collapse during the first minute of life. Our analysis starts a few tenths of seconds after the PNS formation, when the stellar evolution can be described by a sequence of equilibrium configurations. We use the evolutionary models developed by Pons et al. (1999; 2001) that describe how a non rotating star cools down and contracts while neutrino diffusion and thermalization processes dominate the stellar dynamics. For assigned values of the evolution time, we set the star into slow rotation and integrate the equations of stellar perturbations in th…
High-spectral-resolution Fabry-Pérot interferometers overcome fundamental limitations of present volcanic gas remote sensing techniques
2023
Remote sensing (RS) of volcanic gases has become a central tool for studying volcanic activity. For instance, ultraviolet (UV) skylight spectroscopy with grating spectrographs (GS) enables SO2 (and, under favourable conditions, BrO) quantification in volcanic plumes from autonomous platforms at safe distances. These measurements can serve volcanic monitoring and they cover all stages of volcanic activity in long measurement time series, which substantially contributes to the refinement of theories on volcanic degassing. Infrared (IR) remote sensing techniques are able to measure further volcanic gases (e.g., HF, HCl, CO2, CO). However, the employed Fourier transform spectrometers (FTSs) are…
Assessment of Sentinel-2-MSI Atmospheric Correction Processors and In Situ Spectrometry Waters Quality Algorithms
2022
The validation of algorithms developed from in situ reflectance to estimate water quality variables has the challenge of atmospheric correction (AC) when applied to satellite images. Estimating water quality variables from satellite images requires an accurate estimation of remote sensing reflectances (Rrs) which vary according to the AC applied. Validation processes for both Rrs and water quality algorithms were carried out, relating the in situ Rrs (convoluted to Sentinel-2-MSI spectral response function) with the satellite Rrs coming from different ACs (C2RCC, C2X, C2XC, and Polymer), and also relating the in situ water quality variable data with estimated water quality variable values, …