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Auteur Y. Zhang |
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3D building modelling with digital map, Lidar data and video image sequences / Y. Zhang in Photogrammetric record, vol 20 n° 111 (September - November 2005)
[article]
Titre : 3D building modelling with digital map, Lidar data and video image sequences Type de document : Article/Communication Auteurs : Y. Zhang, Auteur ; Z. Zhang, Auteur ; et al., Auteur Année de publication : 2005 Article en page(s) : pp 285 - 302 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Photogrammétrie numérique
[Termes IGN] aérotriangulation
[Termes IGN] capteur aérien
[Termes IGN] compensation par faisceaux
[Termes IGN] élément d'orientation externe
[Termes IGN] modèle 3D de l'espace urbain
[Termes IGN] modélisation 3D
[Termes IGN] orthoimage
[Termes IGN] texture d'imageRésumé : (Auteur) Three-dimensional (3D) reconstruction and texture mapping of buildings or other man-made objects are key aspects for 3D city landscapes. An effective coarse-to-fine approach for 3D building model generation and texture mapping based on digital photogrammetric techniques is proposed. Three video image sequences, two oblique views of building walls and one vertical view of building roofs, acquired by a digital video camera mounted on a helicopter are used as input images. Lidar data and a coarse two-dimensional (2D) digital vector map used for car navigation are also used as information sources. Automatic aerial triangulation (AAT) suitable for a high overlap image sequence is used to give initial values of camera parameters of each image. To obtain accurate image lines, the correspondence between outlines of the building and their line-features in the image sequences is determined with a coarse-to-fine strategy. A hybrid point/line bundle adjustment is used to ensure the stability and accuracy of reconstruction. Reconstructed buildings with fine textures superimposed on a digital elevation model (DEM) and ortho-image are realistically visualised. Experimental results show that the proposed approach of 3D city model generation has a promising future in many applications. Numéro de notice : A2005-381 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1111/j.1477-9730.2005.00316.x En ligne : https://doi.org/10.1111/j.1477-9730.2005.00316.x Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27517
in Photogrammetric record > vol 20 n° 111 (September - November 2005) . - pp 285 - 302[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 106-05031 RAB Revue Centre de documentation En réserve L003 Disponible Detection of buried targets via active selection of labeled data: Application to sensing subsurface UXO / Y. Zhang in IEEE Transactions on geoscience and remote sensing, vol 42 n° 11 (November 2004)
[article]
Titre : Detection of buried targets via active selection of labeled data: Application to sensing subsurface UXO Type de document : Article/Communication Auteurs : Y. Zhang, Auteur ; X. Liao, Auteur ; L. Carin, Auteur Année de publication : 2004 Article en page(s) : pp 2535 - 2543 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] cible cachée
[Termes IGN] classification
[Termes IGN] détection de cible
[Termes IGN] erreur moyenne quadratique
[Termes IGN] matrice
[Termes IGN] matrice d'information de Fischer
[Termes IGN] mine antipersonnel
[Termes IGN] signature spectraleRésumé : (Auteur) When sensing subsurface targets, such as land-mine and unexploded ordnance (UXO), the target signatures are typically a strong function of environmental and historical circumstances. Consequently, it is difficult to constitute a universal training set for design of detection or classification algorithms. In this paper, we develop an efficient procedure by which information-theoretic concepts are used to design the basis functions and training set, directly from the site-specific measured data specifically, assume that measured data (e.g., induction and/or magnetometer) are available from a given site, unlabeled in the sense that it is not known a priori whether a given signature is associated with a target or clutter. For N signatures, the data may be expressed as {Xi, Yi}i=1,N, where xi is the measured data or buried object i, and yi is the associated unknown binary label (target/nontarget). Let the N xi define the set X. The algorithm works in four steps : 1) the Fisher information matrix is used to select a set of basis functions for the kernel-based algorithm, this step defining a set of n signatures Bn X that are most informative in characterizing the signature distribution of the site; 2) the Fisher information matrix is used again to define a small subset Xs X, composed of those xi for which knowledge of the associated labels yi would be most informative in defining the weights, for the basis functions in Bn ; 3) the buried objects associated with the signatures in Xs., are excavated, yielding the associated labels yi, represented by the set Ys.; and 4) using Bn, Xs, and Ys, a kernel-based classifier is designed for use in classifying all remaining buried objects. This framework is discussed in detail, with example results presented for an actual buried-UXO site. Numéro de notice : A2004-462 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2004.836270 En ligne : https://doi.org/10.1109/TGRS.2004.836270 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26982
in IEEE Transactions on geoscience and remote sensing > vol 42 n° 11 (November 2004) . - pp 2535 - 2543[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-04111 RAB Revue Centre de documentation Revues en salle Disponible Knowledge-based approaches to accurate mapping of mangroves from satellite data / J. Gao in Photogrammetric Engineering & Remote Sensing, PERS, vol 70 n° 11 (November 2004)
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Titre : Knowledge-based approaches to accurate mapping of mangroves from satellite data Type de document : Article/Communication Auteurs : J. Gao, Auteur ; H. Chen, Auteur ; Y. Zhang, Auteur ; et al., Auteur Année de publication : 2004 Article en page(s) : pp 1241 - 1248 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse comparative
[Termes IGN] Auckland
[Termes IGN] carte de la végétation
[Termes IGN] carte thématique
[Termes IGN] classificateur paramétrique
[Termes IGN] classification à base de connaissances
[Termes IGN] classification dirigée
[Termes IGN] image SPOT
[Termes IGN] littoral
[Termes IGN] mangrove
[Termes IGN] précision sémantique
[Termes IGN] raisonnement spatialRésumé : (Auteur) Mangroves are difficult to map accurately from satellite data by means of parametric classification because of their spectral similarity to other coastal vegetation despite their habitat being inside coastal waters. This study aims to improve the mapping accuracy through incorporation of such spatial knowledge about mangroves in the Waitemata Harbor of Auckland, New Zealand, from SPOT data. The spatial knowledge was combined with spectral knowledge in the mapping. Supervised classification was found to map stunted and lush mangroves at an accuracy of, respectively, 46.7 percent and 68.3 percent. These accuracy levels rose, respectively, to 83.3 percent and 96.7 percent after the spatial knowledge was sequentially incorporated into the mapping. A similar accuracy level was achieved from knowledge-based spatial reasoning. If integrated simultaneously with spectral knowledge, spatial knowledge did not improve the accuracy noticeably because of difficulty in gaining quality spectral knowledge. It is concluded that knowledge-based, post-classification processing considerably improves the accuracy of mapping mangroves over parametric classification. Numéro de notice : A2004-456 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : 10.14358/PERS.70.11.1241 En ligne : https://doi.org/10.14358/PERS.70.11.1241 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26976
in Photogrammetric Engineering & Remote Sensing, PERS > vol 70 n° 11 (November 2004) . - pp 1241 - 1248[article]Landsat urban mapping based on a combined spectral-spatial methodology / B. Guindon in Remote sensing of environment, vol 92 n° 2 (15/08/2004)
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Titre : Landsat urban mapping based on a combined spectral-spatial methodology Type de document : Article/Communication Auteurs : B. Guindon, Auteur ; Y. Zhang, Auteur ; C. Dillabaugh, Auteur Année de publication : 2004 Article en page(s) : pp 218 - 232 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] Calgary
[Termes IGN] cartographie urbaine
[Termes IGN] classification
[Termes IGN] données maillées
[Termes IGN] données vectorielles
[Termes IGN] fusion d'images
[Termes IGN] identification automatique
[Termes IGN] image Landsat-TM
[Termes IGN] milieu urbain
[Termes IGN] occupation du sol
[Termes IGN] Ontario (Canada)
[Termes IGN] Ottawa
[Termes IGN] pixel
[Termes IGN] utilisation du solRésumé : (Auteur) Urban mapping using Landsat Thematic Mapper (TM) imagery presents numerous challenges. These include spectral mixing of diverse land cover components within pixels, spectral confusion with other land cover features such as fallow agricultural fields and the fact that urban classes of interest are of the land use and not the land cover category. A new methodology to address these issues is proposed. This approach involves, as a first step, the generation of two independent but rudimentary land cover products, one spectral-based at the pixel level and the other segment-based. These classifications are then merged through a rule-based approach to generate a final product with enhanced land use classes and accuracy. A comprehensive evaluation of derived products of Ottawa, Calgary and cities in southwestern Ontario is presented based on conventional ground reference data as well as inter-classification consistency analyses. Producer accuracies of 78% and 73% have been achieved for urban 'residential' and 'commercial/industrial' classes. respectively. The capability of Landsat TM to detect low density residential areas is assessed based on dwelling and population data derived from aerial photography and the 2001 Canadian census. For low population densities (i.e. below 3000 persons/km2), density is observed to be monotonically related to the fraction of pixels labeled 'residential'. At higher densities, the fraction of pixels labeled 'residential' remains constant due to Landsat's inability to distinguish between high-rise apartment dwellings and commercial/industrial structures. Numéro de notice : A2004-335 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2004.06.015 En ligne : https://doi.org/10.1016/j.rse.2004.06.015 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26862
in Remote sensing of environment > vol 92 n° 2 (15/08/2004) . - pp 218 - 232[article]An initial study on automatic reconstruction of ground DEMs from airborne IfSAR DSMs / Y. Zhang in Photogrammetric Engineering & Remote Sensing, PERS, vol 70 n° 4 (April 2004)
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Titre : An initial study on automatic reconstruction of ground DEMs from airborne IfSAR DSMs Type de document : Article/Communication Auteurs : Y. Zhang, Auteur ; C. Vincent Tao, Auteur ; J.B. Mercer, Auteur Année de publication : 2004 Article en page(s) : pp 427 - 438 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] interféromètrie par radar à antenne synthétique
[Termes IGN] milieu urbain
[Termes IGN] modèle numérique de surfaceRésumé : (Auteur) The demands for ground digital elevation models (DEMs) have been increasing rapidly. Many modern mapping technologies, such as lidar scanning, interferometric SAR (IfSAR), and stereo image matching, are capable of generating digital surface models (DSMs) directly. Research on deriving DEMs from DSMs is a topical area. Airborne IfSAR technology has been in commercial operation since 1996. However, it is still technically challenging to automate the process of generating DEMs from IfSAR DSMs. The lack of scientific studies in this area is mainly caused by the sensitivity and availability of commercial IfSAR data. In this study, researchers have been working with the commercial IfSAR system developer to perform an initial study on automatic reconstruction of ground DEMsfrom IfSAR DSMs. This paper presents a compact and yet efficient version of our developed approach. This approach has been tested by using many IfSAR DSMs in different hilly urban areas with light and moderate variations in relief. An accuracy analysis of the reconstructed ground DEMs against the laser DSMs and DEMs has also been performed to test the reliability and efficiency of our approach. Numéro de notice : A2004-119 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.70.4.427 En ligne : https://doi.org/10.14358/PERS.70.4.427 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26646
in Photogrammetric Engineering & Remote Sensing, PERS > vol 70 n° 4 (April 2004) . - pp 427 - 438[article]Quantitative assessment of a haze suppression methodology for satellite imagery: effect on land cover classification performance / Y. Zhang in IEEE Transactions on geoscience and remote sensing, vol 41 n° 5 (May 2003)PermalinkWater quality retrievals from combined Landsat TM data and ERS-2 SAR data in the Gulf of Finland / Y. Zhang in IEEE Transactions on geoscience and remote sensing, vol 41 n° 3 (March 2003)PermalinkCybercity GIS (CCGIS): integration of DEMs, images, and 3D models / Q. Zhu in Photogrammetric Engineering & Remote Sensing, PERS, vol 68 n° 4 (April 2002)PermalinkBeiträge zum Entwurf von optimalen Beobachtungsplänen für tektonische Überwachungsnetze / Y. Zhang (1987)Permalink