Search results for " Resolution"

Mapping soil and substratum at a very high spatial resolution in the hillslope of Couchey (France)

2012

International audience; In this work, we present a method based on very high spatial resolution (VHSR) aerial images acquired in the visible domain and that map soil surface diversity at the hillslope scale with a spatial resolution of a few centimeters. This method combines aerial VHSR image classification with local soil sampling. Principal component analysis (PCA) and non-supervised classification was performed on image characteristics to define soil surface characteristic classes (SSC). Then soil surface mapping was combined with soil surface descriptions and soil profiles to define soil types by physical and chemical characteristics. As soil results from parent material alteration, ide…

Application of a simple algorithm to estimate daily evapotranspiration from NOAA–AVHRR images for the Iberian Peninsula

2007

International audience; Evapotranspiration (ET) is a key process in land surface–atmosphere studies. It mainly depends on water availability and incoming solar radiation and then reflects the interactions between surface water processes and climate. In this paper, a methodology for retrieving ET from low spatial resolution remote sensing data is presented. It is based on the evaporative fraction concept, and it has been applied to Advanced Very High Resolution Radiometer (AHVRR) data acquired over the Iberian Peninsula. The methodology does not require other data than the data provided by the satellite and may be applied to areas with almost spatially constant atmospheric conditions and whi…

Performances of neural networks for deriving LAI estimates from existing CYCLOPES and MODIS products

2008

International audience; This paper evaluates the performances of a neural network approach to estimate LAI from CYCLOPES and MODIS nadir normalized reflectance and LAI products. A data base was generated from these products over the BELMANIP sites during the 2001-2003 period. Data were aggregated at 3 km x 3 km, resampled at 1/16 days temporal frequency and filtered to reject outliers. VEGETATION and MODIS reflectances show very consistent values in the red, near infrared and short wave infrared bands. Neural networks were trained over part of this data base for each of the 6 MODIS biome classes to retrieve both MODIS and CYCLOPES LAI products. Results show very good performances of neural …

Multitemporal Unmixing of Medium-Spatial-Resolution Satellite Images: A Case Study Using MERIS Images for Land-Cover Mapping

2011

Data from current medium-spatial-resolution imaging spectroradiometers are used for land-cover mapping and land-cover change detection at regional to global scales. However, few landscapes are homogeneous at these scales, and this creates the so-called mixed-pixel problem. In this context, this study explores the use of the linear spectral mixture model to extract subpixel land-cover composition from medium-spatial-resolution data. In particular, a time series of MEdium Resolution Imaging Spectrometer (MERIS) full-resolution (FR; pixel size of 300 m) images acquired over The Netherlands is used to illustrate this study. The Netherlands was selected because of the following: 1) the fragmenta…

SUPER-RESOLUTION IMAGES ON MOBILE SMARTPHONE AIMED AT 3D MODELING

2022

Abstract. In these last years have been calculated several general algorithms to process the images acquired by mobile devices. Nevertheless, they don't always work at their full effectiveness due the numerous constraints and external issues. The latest generation smartphones, pushed by higher user expectations, have increasingly performing camera functions, in particular way, about the always increasing resolution, with a large number of pixels to process or two cameras for stereo view. Considering that pixels in an image sensor synthetizes the number of incoming photons, taking a photograph with a digital camera means to applying a low-pass filter to a scene where the tiny textures, such …

Neutral Iron Emission Lines From The Day-side Of KELT-9b -- The GAPS Programme With HARPS-N At TNG XX

2020

We present the first detection of atomic emission lines from the atmosphere of an exoplanet. We detect neutral iron lines from the day-side of KELT-9b (Teq $\sim$ 4, 000 K). We combined thousands of spectrally resolved lines observed during one night with the HARPS-N spectrograph (R $\sim$ 115, 000), mounted at the Telescopio Nazionale Galileo. We introduce a novel statistical approach to extract the planetary parameters from the binary mask cross-correlation analysis. We also adapt the concept of contribution function to the context of high spectral resolution observations, to identify the location in the planetary atmosphere where the detected emission originates. The average planetary li…

Asymmetric Synthesis of Chiral Bimetallic [Ag28Cu12(SR)24]4– Nanoclusters via Ion Pairing

2016

In this work, a facile ion-pairing strategy for asymmetric synthesis of optically active negatively charged chiral metal nanoparticles using chiral ammonium cations is demonstrated. A new thiolated chiral three-concentric-shell cluster, [Ag28Cu12(SR)24]4–, was first synthesized as a racemic mixture and characterized by single-crystal X-ray structure determination. Mass spectrometric measurements revealed relatively strong ion-pairing interactions between the anionic nanocluster and ammonium cations. Inspired by this observation, the as-prepared racemic mixture was separated into enantiomers by employing chiral quaternary ammonium salts as chiral resolution agents. Subsequently, direct asymm…

Riflessioni critiche sul collegamento fra autotutela sostitutiva e principio di perennità’ dell’azione impositiva

2023

Con opinabile orientamento, la Suprema Corte ha esteso i confini dell’autotutela c.d. sostitutiva fino a ricomprendervi un principio di “perennità” dell’azione amministrativa, che mal si raccorda, laddove non ne nega addirittura la ratio sottostante, con la disciplina positiva che regola i presupposti per l’esercizio della funzione impositiva e per la sua rinnovazione. Siffatto principio, peraltro, appare in contrasto con quello della “buona amministrazione” (diretta declinazione dell’art. 97 Cost.) nella misura in cui essa trova la sua moderna dimensione nell’essere anche strumento di tutela dell’amministrato dall’esercizio (extra ordinem) dei pubblici poteri. The Italian Supreme Court has…

Exploring evolutionary responses to increasing temperature in an environmental opportunistic pathogen

2017

Molecular Signatures of Biogeochemical Transformations in Dissolved Organic Matter from Ten World Rivers

2016

Rivers carry large amounts of dissolved organic matter (DOM) to the oceans thereby connecting terrestrial and marine element cycles. Photo-degradation in conjunction with microbial turnover is considered a major pathway by which terrigenous DOM is decomposed. To reveal globally relevant patterns behind this process, we performed photo-degradation experiments and year-long bio-assays on DOM from ten of the largest world rivers that collectively account for more than one-third of the fresh water discharge to the global ocean. We furthermore tested the hypothesis that the terrigenous component in deep-sea DOM may be far higher than biomarker studies suggest, because of the selective photochemi…