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Amundsen Sea bathymetry: the benefits of using gravity data for bathymetric prediction / M. Mcmillan in IEEE Transactions on geoscience and remote sensing, vol 47 n° 12 Tome 2 (December 2009)
[article]
Titre : Amundsen Sea bathymetry: the benefits of using gravity data for bathymetric prediction Type de document : Article/Communication Auteurs : M. Mcmillan, Auteur ; A. Sheperd, Auteur ; D. Vaughan, Auteur ; et al., Auteur Année de publication : 2009 Article en page(s) : pp 4223 - 4228 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bathymétrie
[Termes IGN] Amundsen, mer d'
[Termes IGN] Arctique, océan
[Termes IGN] données altimétriques
[Termes IGN] fond marin
[Termes IGN] gravimétrie en mer
[Termes IGN] image ERS
[Termes IGN] levé gravimétrique
[Termes IGN] méthode de Monte-Carlo
[Termes IGN] plateau continental
[Termes IGN] prédiction
[Termes IGN] profondeurRésumé : (Auteur) Bathymetric charts are essential for modeling oceanic processes, yet, in remote areas, direct measurements of seafloor depth are often scarce. It is possible to augment sparse depth soundings with dense satellite-derived gravity data to provide additional bathymetric detail in regions devoid of sounding data. We demonstrate this method by using marine gravity derived from the European Remote Sensing (ERS-1) satellite altimeter, combined with depth soundings, to form a bathymetric prediction of the Amundsen Sea, West Antarctica. We estimate the root mean square error of depth estimates at unsurveyed locations in our solution to be ~120 m. We use a Monte Carlo method to assess the value of gravity as a bathymetric predictor in sparsely surveyed regions by comparing our solution to predictions formed from depth soundings alone. When less than ~11% of 10-km grid cells contain depth soundings, inclusion of gravity data improves the depth accuracy of the solution by up to 17%, as compared to a minimum curvature surface interpolation of the depth soundings alone. When depth data are sparse, our gravity-derived prediction reveals additional short-wavelength bathymetric features, such as troughs on the continental shelf, which are not resolved by interpolations of the depth soundings alone. Copyright IEEE Numéro de notice : A2009-493 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2009.2023665 En ligne : https://doi.org/10.1109/TGRS.2009.2023665 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30122
in IEEE Transactions on geoscience and remote sensing > vol 47 n° 12 Tome 2 (December 2009) . - pp 4223 - 4228[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-09121B RAB Revue Centre de documentation En réserve L003 Disponible Interferometric SAR for characterization of ravines as a function of their density, depth, and surface cover / R.S. Chatterjee in ISPRS Journal of photogrammetry and remote sensing, vol 64 n° 5 (September - October 2009)
[article]
Titre : Interferometric SAR for characterization of ravines as a function of their density, depth, and surface cover Type de document : Article/Communication Auteurs : R.S. Chatterjee, Auteur ; S. Saha, Auteur ; Satish Kumar, Auteur ; et al., Auteur Année de publication : 2009 Article en page(s) : pp 472 - 481 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] bande C
[Termes IGN] caractérisation
[Termes IGN] érosion hydrique
[Termes IGN] image ERS-SAR
[Termes IGN] image radar moirée
[Termes IGN] Inde
[Termes IGN] interféromètrie par radar à antenne synthétique
[Termes IGN] profondeurRésumé : (Auteur) In recent years, the problem of ravine erosion with consequent loss of usable land has received much attention worldwide. The Chambal ravine zone in India is well known for being an extremely intricate, deeply incised network of ravines in a 10 km wide zone on the flanks of the Chambal River. It occupies an area of not, vert, similar0.5 million hectares at the expense of fertile agricultural land of the Chambal Valley. The broad grouping of the ravines considering their reclamation potential, as carried out by previous workers based on visual interpretation of optical remote sensing data, is mostly descriptive in nature. In the present study, characterization of the ravines as a function of their erosion potential expressed through ravine density, ravine depth, and ravine surface cover was made in quantitative terms exploiting the preferential characteristics of side-looking, long-wavelength, coherent SAR signal and precision measurements associated with the InSAR technique. The outlines of ravines appear remarkably prominent in SAR backscattered amplitude images due to the high sensitivity of the SAR signal to terrain ruggedness. Using local statistics-based meso and macro textural information of SAR backscattered amplitude images in 7*7 pixel windows (the pixel size being 20 m*20 m), the ravine-affected area has been classified into three density classes, namely low, moderate, and high density ravine classes. C-band InSAR digital elevation models (DEMs) of sparsely vegetated ravine areas essentially give the terrain height. From the pixel-by-pixel terrain height, the ravine depth was calculated by differencing the maximum and minimum terrain heights of the pixels in a 100 m distance range. Considering the vertical precision of the ERS InSAR DEMs of not, vert, similar5 m and ravine depth classification by previous workers [Sharma, H.S., 1968. Genesis and pattern of ravines of the Lower Chambal Valley, India. Special Issue. 21st International Geographical Union Congress 30(4), 14–24; Seth, S.P., Bhatnagar, R.K., Chauhan, S.S., 1969. Reclamability classification and nature of ravines of Chambal Command Areas. Journal of Soil and Water Conservation in India 17 (3–4), 39–44.], three depth classes, namely shallow (20 m) ravines, were made. Using the temporal decorrelation property of the close time interval InSAR data pair, namely the ERS SAR tandem pair, four ravine surface cover classes, namely barren land, grass/scrub/crop land, sparse vegetation, and wet land/dense vegetation, could be delineated, which was corroborated by the spectral signatures in the optical range and selective ground truths. Copyright ISPRS Numéro de notice : A2009-400 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2008.12.005 En ligne : https://doi.org/10.1016/j.isprsjprs.2008.12.005 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30031
in ISPRS Journal of photogrammetry and remote sensing > vol 64 n° 5 (September - October 2009) . - pp 472 - 481[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-09051 SL Revue Centre de documentation Revues en salle Disponible GIS modeling of wave exposure at the seabed: a depth-attenuated wave exposure model / T. Bekkby in Marine geodesy, vol 31 n° 2 (June - September 2008)
[article]
Titre : GIS modeling of wave exposure at the seabed: a depth-attenuated wave exposure model Type de document : Article/Communication Auteurs : T. Bekkby, Auteur ; E. Isachsen, Auteur ; et al., Auteur Année de publication : 2008 Article en page(s) : pp 117 - 127 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications SIG
[Termes IGN] eaux côtières
[Termes IGN] faune aquatique
[Termes IGN] modèle océanographique
[Termes IGN] océanographie spatiale
[Termes IGN] profondeur
[Termes IGN] relief sous-marin
[Termes IGN] Stockholm (Suède)
[Termes IGN] substrat
[Termes IGN] système d'information géographique
[Termes IGN] vagueRésumé : (Auteur) Several studies have documented relationships between wave exposure and distribution, density, and size of marine species. Hence, this factor is at a high level in the hierarchical habitat classification system EUNIS and is one of the Water Framework Directive water typology criteria of coastal waters. Isaeligus (2004) has developed a continuous simplified wave model (SWM) that has been applied to several Nordic countries. Here we refine this model by introducing depth-attenuation, giving us the advantage of a model for wave exposure as it will actually work at the seabed. The values of the depth-attenuated model SWM(d) are approximately similar to the SWM model in shallow areas but noticeably lower in deep areas. The two models were compared in an analysis of the distribution of seabed substrate in the Stockholm archipelago. Using the depth-attenuated wave exposure instead of the SWM model as predictor in substrate modeling improved these models considerably. Copyright Taylor & Francis Numéro de notice : A2008-497 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/01490410802053674 En ligne : https://doi.org/10.1080/01490410802053674 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29566
in Marine geodesy > vol 31 n° 2 (June - September 2008) . - pp 117 - 127[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 230-08021 RAB Revue Centre de documentation En réserve L003 Disponible Image-based 3D surface reconstruction by combination of photometric, geometric, and real-aperture methods / Pablo d' Angelo in ISPRS Journal of photogrammetry and remote sensing, vol 63 n° 3 (May - June 2008)
[article]
Titre : Image-based 3D surface reconstruction by combination of photometric, geometric, and real-aperture methods Type de document : Article/Communication Auteurs : Pablo d' Angelo, Auteur ; C. Wöhler, Auteur Année de publication : 2008 Article en page(s) : pp 297 - 321 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Photogrammétrie numérique
[Termes IGN] données de terrain
[Termes IGN] gradient de pente
[Termes IGN] pente
[Termes IGN] photométrie
[Termes IGN] polarisation
[Termes IGN] profondeur
[Termes IGN] programmation non linéaire
[Termes IGN] reconstruction 3D
[Termes IGN] réflectanceRésumé : (Auteur) An image-based 3D surface reconstruction method based on simultaneous evaluation of intensity and polarisation features (shape from photopolarimetric reflectance) and its combination with absolute depth data is introduced in this article. The proposed technique is based on the analysis of single or multiple intensity and polarisation images. To compute the surface gradients, we present a global optimisation method based on a variational framework and a local optimisation method based on solving a set of non-linear equations individually for each image pixel. These approaches are suitable for strongly non-Lambertian surfaces and those of diffuse reflectance behaviour and can also be adapted to surfaces of non-uniform albedo. We describe how independently measured absolute depth data is integrated into the shape from photopolarimetric reflectance framework in order to increase the accuracy of the 3D reconstruction result. In this context we concentrate on dense but noisy depth data obtained by depth from defocus and on sparse but accurate depth data obtained by stereo or structure from motion analysis. We show that depth from defocus information should preferentially be used for initialising the optimisation schemes for the surface gradients. For integration of sparse depth information, we suggest an optimisation scheme that simultaneously adapts the surface gradients to the measured intensity and polarisation data and to the surface slopes implied by depth differences between pairs of depth points. In principle, arbitrary sources of depth information are possible in the presented framework. Experiments on synthetic and on real-world data reveal that while depth from defocus is especially helpful for providing an initial estimate of the surface gradients and the albedo in the absence of a-priori knowledge, integration of stereo or structure from motion information significantly increases the 3D reconstruction accuracy. In our real-world experiments, we regard the scenarios of 3D reconstruction of raw forged iron surfaces in the domain of industrial quality inspection and the generation of a digital elevation model of a section of the lunar surface in the context of space-based planetary exploration. Copyright ISPRS Numéro de notice : A2008-213 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2007.09.005 En ligne : https://doi.org/10.1016/j.isprsjprs.2007.09.005 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29208
in ISPRS Journal of photogrammetry and remote sensing > vol 63 n° 3 (May - June 2008) . - pp 297 - 321[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-08031 SL Revue Centre de documentation Revues en salle Disponible Acquisitions sensors: part 1 multibeam echo sounder / Huibert-Jan Lekkerkerk in Geoinformatics, vol 11 n° 3 (01/04/2008)
[article]
Titre : Acquisitions sensors: part 1 multibeam echo sounder Type de document : Article/Communication Auteurs : Huibert-Jan Lekkerkerk, Auteur Année de publication : 2008 Article en page(s) : pp 48 - 51 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bathymétrie
[Termes IGN] bathymétrie acoustique
[Termes IGN] fond marin
[Termes IGN] modèle numérique bathymétrique
[Termes IGN] onde acoustique
[Termes IGN] profondeur
[Termes IGN] relief sous-marin
[Termes IGN] sondeur multifaisceaux
[Termes IGN] télédétection acoustiqueRésumé : (Auteur) The first step in any geo-information process is the acquisition of data. In this new series we will describe different types of acquisition sensors in detail. With this issue being a water special, the first acquisition sensor to be analysed is the multibeam echo sounder. Copyright GEOinformatics Numéro de notice : A2008-135 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29130
in Geoinformatics > vol 11 n° 3 (01/04/2008) . - pp 48 - 51[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 262-08031 SL Revue Centre de documentation Revues en salle Disponible Épaisseur d'eau minimale mesurable en rivière sur fronts d'ondes lidar simulés / A. Lesaignoux in Revue Française de Photogrammétrie et de Télédétection, n° 186 (Juin 2007)PermalinkAutomated subpixel photobathymetry and water quality mapping / R.L. Huguenin in Photogrammetric Engineering & Remote Sensing, PERS, vol 70 n° 1 (January 2004)PermalinkAnalyse d'images aériennes haute résolution : détection et modélisation du bâti en zone urbaine / Matthieu Cord (1998)PermalinkLes possibilités de la photographie aérienne pour l'étude des faibles profondeurs de la marge continentale et des fleuves / Albert Clos-Arceduc (1969)Permalink