Descripteur



Etendre la recherche sur niveau(x) vers le bas
GTP-PNet: A residual learning network based on gradient transformation prior for pansharpening / Hao Zhang in ISPRS Journal of photogrammetry and remote sensing, vol 172 (February 2021)
![]()
[article]
Titre : GTP-PNet: A residual learning network based on gradient transformation prior for pansharpening Type de document : Article/Communication Auteurs : Hao Zhang, Auteur ; Jiayi Ma, Auteur Année de publication : 2021 Article en page(s) : pp 223 - 239 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes descripteurs IGN] apprentissage profond
[Termes descripteurs IGN] classification dirigée
[Termes descripteurs IGN] fusion d'images
[Termes descripteurs IGN] gradient
[Termes descripteurs IGN] image multibande
[Termes descripteurs IGN] image panchromatique
[Termes descripteurs IGN] Normalized Difference Vegetation Index
[Termes descripteurs IGN] pansharpening (fusion d'images)
[Termes descripteurs IGN] régressionRésumé : (auteur) Pansharpening aims to fuse low-resolution multi-spectral image and high-resolution panchromatic (PAN) image to produce a high-resolution multi-spectral (HRMS) image. In this paper, a new residual learning network based on gradient transformation prior, termed as GTP-PNet, is proposed to generate the high-quality HRMS image with accurate spectral distribution as well as reasonable spatial structure. Different from previous deep models that only rely on supervision of the HRMS reference image, we introduce the gradient transformation prior to the deep model, so as to improve the solution accuracy. Our model consists of two networks, namely gradient transformation network (TNet) and pansharpening network (PNet). TNet is committed to seeking the nonlinear mapping between gradients of PAN and HRMS images, which is essentially a spatial relationship regression of imaging bands in different ranges. PNet is the residual learning network used to generate the HRMS image, which is not only supervised by the HRMS reference image, but also constrained by the trained TNet. As a result, the HRMS image generated by PNet not only approximates the HRMS reference image in the spectral distribution, but also conforms to the gradient transformation prior in the spatial structure. Experimental results demonstrate the significant superiority of our method over the current state-of-the-arts in terms of both subjective visual effect and quantitative metrics. We also apply our method to produce the HR normalized difference vegetation index in remote sensing, which can achieve the best performance. Moreover, our method is much competitive compared with the state-of-the-art alternatives in running efficiency. Numéro de notice : A2021-089 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2020.12.014 date de publication en ligne : 11/01/2021 En ligne : https://doi.org/10.1016/j.isprsjprs.2020.12.014 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96859
in ISPRS Journal of photogrammetry and remote sensing > vol 172 (February 2021) . - pp 223 - 239[article]Réservation
Réserver ce documentExemplaires (2)
Code-barres Cote Support Localisation Section Disponibilité 081-2021021 SL Revue Centre de documentation Revues en salle Disponible 081-2021022 DEP-RECF Revue Nancy Bibliothèque Nancy IFN Disponible SAR image speckle reduction based on nonconvex hybrid total variation model / Yuli Sun in IEEE Transactions on geoscience and remote sensing, vol 59 n° 2 (February 2021)
![]()
[article]
Titre : SAR image speckle reduction based on nonconvex hybrid total variation model Type de document : Article/Communication Auteurs : Yuli Sun, Auteur ; Lin Lei, Auteur ; Dongdong Guan, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : pp 1231 - 1249 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes descripteurs IGN] artefact
[Termes descripteurs IGN] chatoiement
[Termes descripteurs IGN] détection de contours
[Termes descripteurs IGN] distribution de Fisher
[Termes descripteurs IGN] gradient
[Termes descripteurs IGN] image radar moirée
[Termes descripteurs IGN] régularisation d'image
[Termes descripteurs IGN] variableRésumé : (auteur) Speckle noise inherent in synthetic aperture radar (SAR) images seriously affects the visual effect and brings great difficulties to the postprocessing of the SAR image. Due to the edge-preserving feature, total variation (TV) regularization-based techniques have been extensively utilized to reduce the speckle. However, the strong scatters in SAR image with radiometry several orders of magnitude larger than their surrounding regions limit the effectiveness of TV regularization. Meanwhile, the ℓ1 -norm first-order TV regularization sometimes causes staircase artifacts as it favors solutions that are piecewise constant, and it usually underestimates high-amplitude components of image gradient as the ℓ1 -norm uniformly penalizes the amplitude. To overcome these shortcomings, a new hybrid variation model, called Fisher–Tippett (FT) distribution- ℓp -norm first-and second-order hybrid TVs (HTpVs), is proposed to reduce the speckle after removing the strong scatters. Especially, the FT-HTpV inherits the advantages of the distribution based data fidelity term, the nonconvex regularization, and the higher order TV regularization. Therefore, it can effectively remove the speckle while preserving point scatters and edges and reducing staircase artifacts well. To efficiently solve the nonconvex minimization problem, an iterative framework with a nonmonotone-accelerated proximal gradient (nmAPG) method and a matrix-vector acceleration strategy are used. Extensive experiments on both the simulated and real SAR images demonstrate the effectiveness of the proposed method. Numéro de notice : A2021-114 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2020.3002561 date de publication en ligne : 08/07/2020 En ligne : https://doi.org/10.1109/TGRS.2020.3002561 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96924
in IEEE Transactions on geoscience and remote sensing > vol 59 n° 2 (February 2021) . - pp 1231 - 1249[article]Turgor – a limiting factor for radial growth in mature conifers along an elevational gradient / Richard L. Peters in New phytologist, vol 229 n° 1 (January 2021)
![]()
[article]
Titre : Turgor – a limiting factor for radial growth in mature conifers along an elevational gradient Type de document : Article/Communication Auteurs : Richard L. Peters, Auteur ; Kathy Steppe, Auteur ; Henri E. Cuny , Auteur ; Dirk J.W. de Pauw, Auteur ; David Frank, Auteur ; Marcus Schaub, Auteur ; Cyrille B.K. Rathgeber, Auteur ; Antoine Cabon, Auteur ; Patrick Fonti, Auteur
Année de publication : 2021 Projets : 3-projet - voir note / Article en page(s) : pp 213 - 229 Note générale : bibliographie
Funding information : COST Action network. Grant Number: STReESS/FP1106 -&- Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung. Grant Numbers: CLIMWOOD/160077, Early Postdoc.Mobility/P2BSP3_184475, LOTFOR/150205Langues : Anglais (eng) Descripteur : [Termes descripteurs IGN] cerne
[Termes descripteurs IGN] changement climatique
[Termes descripteurs IGN] croissance végétale
[Termes descripteurs IGN] gradient
[Termes descripteurs IGN] gradient de pente
[Termes descripteurs IGN] Larix decidua
[Termes descripteurs IGN] modèle de croissance
[Termes descripteurs IGN] modèle de simulation
[Termes descripteurs IGN] Picea abies
[Termes descripteurs IGN] pinophyta
[Termes descripteurs IGN] puits de carbone
[Termes descripteurs IGN] sécheresse
[Vedettes matières IGN] Végétation et changement climatiqueRésumé : (auteur) A valid representation of intra‐annual wood formation processes in global vegetation models is vital for assessing climate change impacts on the forest carbon stock. Yet, wood formation is generally modelled with photosynthesis, despite mounting evidence that cambial activity is rather directly constrained by limiting environmental factors. Here, we apply a state‐of‐the‐art turgor‐driven growth model to simulate 4 yr of hourly stem radial increment from Picea abies (L.) Karst. and Larix decidua Mill. growing along an elevational gradient. For the first time, wood formation observations were used to validate weekly to annual stem radial increment simulations, while environmental measurements were used to assess the climatic constraints on turgor‐driven growth. Model simulations matched the observed timing and dynamics of wood formation. Using the detailed model outputs, we identified a strict environmental regulation on stem growth (air temperature > 2°C and soil water potential > −0.6 MPa). Warmer and drier summers reduced the growth rate as a result of turgor limitation despite warmer temperatures being favourable for cambial activity. These findings suggest that turgor is a central driver of the forest carbon sink and should be considered in next‐generation vegetation models, particularly in the context of global warming and increasing frequency of droughts. Numéro de notice : A2021-063 Affiliation des auteurs : IGN+Ext (2020- ) Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/nph.16872 date de publication en ligne : 07/12/2020 En ligne : https://doi.org/10.1111/nph.16872 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96863
in New phytologist > vol 229 n° 1 (January 2021) . - pp 213 - 229[article]Using quantum optical sensors for determining the Earth’s gravity field from space / Jurgen Müller in Journal of geodesy, vol 94 n° 8 (August 2020)
![]()
[article]
Titre : Using quantum optical sensors for determining the Earth’s gravity field from space Type de document : Article/Communication Auteurs : Jurgen Müller, Auteur ; Hu Wu, Auteur Année de publication : 2020 Article en page(s) : n° 71 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes descripteurs IGN] capteur optique
[Termes descripteurs IGN] champ de pesanteur terrestre
[Termes descripteurs IGN] données GOCE
[Termes descripteurs IGN] données GRACE
[Termes descripteurs IGN] gradient
[Termes descripteurs IGN] gradiomètre
[Termes descripteurs IGN] gravimétrie spatiale
[Termes descripteurs IGN] horloge du satellite
[Termes descripteurs IGN] incertitude temporelle
[Termes descripteurs IGN] longueur d'onde
[Termes descripteurs IGN] onde myriamétrique
[Termes descripteurs IGN] optique quantiqueRésumé : (auteur) Quantum optical technology provides an opportunity to develop new kinds of gravity sensors and to enable novel measurement concepts for gravimetry. Two candidates are considered in this study: the cold atom interferometry (CAI) gradiometer and optical clocks. Both sensors show a high sensitivity and long-term stability. They are assumed on board of a low-orbit satellite like gravity field and steady-state ocean circulation explorer (GOCE) and gravity recovery and climate experiment (GRACE) to determine the Earth’s gravity field. Their individual contributions were assessed through closed-loop simulations which rigorously mapped the sensors’ sensitivities to the gravity field coefficients. Clocks, which can directly obtain the gravity potential (differences) through frequency comparison, show a high sensitivity to the very long-wavelength gravity field. In the GRACE orbit, clocks with an uncertainty level of 1.0×10−18 are capable to retrieve temporal gravity signals below degree 12, while 1.0×10−17 clocks are useful for detecting the signals of degree 2 only. However, it poses challenges for clocks to achieve such uncertainties in a short time. In space, the CAI gradiometer is expected to have its ultimate sensitivity and a remarkable stability over a long time (measurements are precise down to very low frequencies). The three diagonal gravity gradients can properly be measured by CAI gradiometry with a same noise level of 5.0 mE/Hz−−−√. They can potentially lead to a 2–5 times better solution of the static gravity field than that of GOCE above degree and order 50, where the GOCE solution is mainly dominated by the gradient measurements. In the lower degree part, benefits from CAI gradiometry are still visible, but there, solutions from GRACE-like missions are superior. Numéro de notice : A2020-537 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-020-01401-8 date de publication en ligne : 24/07/2020 En ligne : https://doi.org/10.1007/s00190-020-01401-8 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95730
in Journal of geodesy > vol 94 n° 8 (August 2020) . - n° 71[article]Etablissement d’une mesure gravimétrique absolue et d’un gradient vertical d’accélération de pesanteur dans les locaux du Laboratoire national d’essais (LNE) à Paris 15ème / Renaud Degoy (2020)
Titre : Etablissement d’une mesure gravimétrique absolue et d’un gradient vertical d’accélération de pesanteur dans les locaux du Laboratoire national d’essais (LNE) à Paris 15ème Type de document : Rapport Auteurs : Renaud Degoy, Auteur Editeur : Saint-Mandé : Institut national de l'information géographique et forestière - IGN Année de publication : 2020 Collection : Publications techniques en géodésie num. 600828675-02 Importance : 21 p. Format : 21 x 30 cm Langues : Français (fre) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes descripteurs IGN] accélération de la pesanteur
[Termes descripteurs IGN] gradient
[Termes descripteurs IGN] levé gravimétriqueNote de contenu : 1- Contexte
2- Equipement et numérotation
3- Observations
4- Traitements
5- Résultats
6- AnnexesNuméro de notice : 28547 Affiliation des auteurs : IGN+Ext (2020- ) Thématique : POSITIONNEMENT Nature : Rapport nature-HAL : Rapport Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97408 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 28547-01 7D Livre SGN K001 Exclu du prêt PermalinkContext pyramidal network for stereo matching regularized by disparity gradients / Junhua Kang in ISPRS Journal of photogrammetry and remote sensing, vol 157 (November 2019)
PermalinkAutomatic registration of images to untextured geometry using average shading gradients / Tobias Plötz in International journal of computer vision, vol 125 n° 1-3 (December 2017)
PermalinkOn the determination of the effect of horizontal ionospheric gradients on ranging errors in GNSS positioning / Ekaterina A. Danilogorskaya in Journal of geodesy, vol 91 n° 5 (May 2017)
PermalinkPermalinkFloristic composition and across-track reflectance gradient in Landsat images over Amazonian forests / Javier Muro in ISPRS Journal of photogrammetry and remote sensing, vol 119 (September 2016)
PermalinkA methodology for near real-time change detection between Unmanned Aerial Vehicle and wide area satellite images / Anastasios L. Fytsilis in ISPRS Journal of photogrammetry and remote sensing, vol 119 (September 2016)
PermalinkGenetic differentiation of European larch along an altitudinal gradient in the French Alps / Maxime Nardin in Annals of Forest Science [en ligne], vol 72 n° 5 (July 2015)
PermalinkUn approche esthétique pour l'enseignement de la composition de gradients colorés / Laurent Jégou in Cartes & Géomatique, n° 222 (décembre 2014)
PermalinkA fast volume-gradient-based band selection method for hyperspectral image / X. Geng in IEEE Transactions on geoscience and remote sensing, vol 52 n° 11 tome 1 (November 2014)
Permalink