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A method for drawing vertical curve in longitudinal profile in road project / Hüseyin İnce in Survey review, vol 51 n° 368 (September 2019)
[article]
Titre : A method for drawing vertical curve in longitudinal profile in road project Type de document : Article/Communication Auteurs : Hüseyin İnce, Auteur ; Nuri Erdem, Auteur Année de publication : 2019 Article en page(s) : pp 413 - 421 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse numérique
[Termes IGN] courbe
[Termes IGN] échelle cartographique
[Termes IGN] gradient de pente
[Termes IGN] profil en long
[Termes IGN] projet routierRésumé : (Auteur) In road projects, there is a difficulty in drawing tangent points of the calculated vertical curve, turning point and intermediate points due to horizontal and vertical scale differences. This problem is brought about by the fact that proportional relationship between the two different scales is not known for a length with a certain slope in longitudinal profile. This study proposes a method to eliminate this problem. It also gives an example and discusses the findings. Numéro de notice : A2019-367 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/00396265.2018.1470071 Date de publication en ligne : 15/05/2018 En ligne : https://doi.org/10.1080/00396265.2018.1470071 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93473
in Survey review > vol 51 n° 368 (September 2019) . - pp 413 - 421[article]
Titre : Contour lines generation in karstic plateaus for topographic maps Type de document : Article/Communication Auteurs : Guillaume Touya , Auteur ; Hugo Boulze , Auteur ; Anouk Schleich, Auteur ; Hervé Quinquenel , Auteur Editeur : International Cartographic Association ICA - Association cartographique internationale ACI Année de publication : 2019 Autre Editeur : Göttingen : Copernicus publications Collection : Proceedings of the ICA Projets : 1-Pas de projet / Conférence : ICC 2019, 29th International Cartographic Conference ICA, Mapping everything for everyone 15/07/2019 20/07/2019 Tokyo Japon Open Access Proceedings of the ICA Importance : 8 p. Format : 21 x 30 cm Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] carte topographique
[Termes IGN] contour
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] effondrement de terrain
[Termes IGN] grotte
[Termes IGN] Jura, massif du
[Termes IGN] karst
[Termes IGN] lissage de données
[Termes IGN] modèle numérique de terrain
[Termes IGN] QGISRésumé : (auteur) Contour lines are a key features of topographic maps as they make the comprehension of terrain more easy. But they are no longer drawn by cartographers, they are mostly automatically derived from digital terrain models. Despite real progress in this automated derivation, some specific terrain landscapes remain incorrectly depicted with such techniques, and this is the case for karstic plateaus full of sinkholes. This paper proposes a specific automated method to derive better contour lines in plateaus, particularly around sinkholes. The process first detects karstic plateaus with many sinkholes, as well as the individual sinkholes. Then, the DTM is smoothed to better reflect the terrain in the plateau and in its surroundings. As a third step, the contour lines around sinkholes are enhanced to draw legible round features that better reflect the real terrain. The process was implemented in a QGIS plugin and tested on a small area with a karstic plateau in the Jura mountain in France, and the cartographers of IGN, the French national mapping agency assessed the results as a great improvement compared to the generic automated process to derive contour lines. Numéro de notice : C2019-011 Affiliation des auteurs : LASTIG COGIT (2012-2019) Thématique : GEOMATIQUE/IMAGERIE Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : 10.5194/ica-proc-2-133-2019 Date de publication en ligne : 10/07/2019 En ligne : http://dx.doi.org/10.5194/ica-proc-2-133-2019 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93259 Voir aussiDocuments numériques
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Contour lines generation - pdf éditeurAdobe Acrobat PDF DEM refinement by low vegetation removal based on the combination of full waveform data and progressive TIN densification / Hongchao Ma in ISPRS Journal of photogrammetry and remote sensing, vol 146 (December 2018)
[article]
Titre : DEM refinement by low vegetation removal based on the combination of full waveform data and progressive TIN densification Type de document : Article/Communication Auteurs : Hongchao Ma, Auteur ; Weiwei Zhou, Auteur ; Liang Zhang, Auteur Année de publication : 2018 Article en page(s) : pp 260 - 271 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] algorithme de Levenberg-Marquardt
[Termes IGN] coefficient de rétrodiffusion
[Termes IGN] contour
[Termes IGN] décomposition de Gauss
[Termes IGN] densification
[Termes IGN] extraction de la végétation
[Termes IGN] filtrage de la végétation
[Termes IGN] forme d'onde pleine
[Termes IGN] hauteur de la végétation
[Termes IGN] modèle numérique de surface
[Termes IGN] semis de points
[Termes IGN] signal laser
[Termes IGN] Triangulated Irregular NetworkRésumé : (Auteur) Filtering of low vegetation with height less than approximately 1.5 m is a challenging problem, especially in mountainous areas covered by heavy low foliage, bushes and sub-shrubberies, etc. The paper proposes an approach for obtaining a more accurate Digital Elevation Model (DEM) by removing low vegetation from point cloud. The approach combines point cloud with full waveform data, and begins by filtering point cloud by way of progressive TIN densification (PTD) method. Ground points are thus extracted, but mixed with false ground points, which are mainly from low vegetation and other manmade low objects. Gaussian decomposition by grouping Levenberg–Marquardt (LM) algorithm with F test is performed for the full waveforms corresponding to the extracted ground points. Echo widths and backscattering coefficients are calculated based on the parameters extracted from the decomposition, and used to discriminate points of low vegetation from points of other low objects, allowing the false ground points reflected from low vegetation to be labeled. New elevation values are calculated from the last echoes of the waveforms from low vegetation, and the DEM is updated by replacing the original elevations with the calculated ones. The resultants are assessed both quantitatively by check points and qualitatively by rendered DEM and contour lines generated from it. The accuracy of the refined DEM with low vegetation removal increases by 31% compared with the original DEM in the experiment, showing the effectiveness of the proposed approach. Numéro de notice : A2018-539 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2018.09.009 Date de publication en ligne : 21/10/2018 En ligne : https://doi.org/10.1016/j.isprsjprs.2018.09.009 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91553
in ISPRS Journal of photogrammetry and remote sensing > vol 146 (December 2018) . - pp 260 - 271[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-2018131 RAB Revue Centre de documentation En réserve L003 Disponible 081-2018133 DEP-EXM Revue LASTIG Dépôt en unité Exclu du prêt 081-2018132 DEP-EAF Revue Nancy Dépôt en unité Exclu du prêt Historic reconstruction of reservoir topography using contour line interpolation and structure from motion photogrammetry / Ana Casado in International journal of geographical information science IJGIS, vol 32 n° 11-12 (November - December 2018)
[article]
Titre : Historic reconstruction of reservoir topography using contour line interpolation and structure from motion photogrammetry Type de document : Article/Communication Auteurs : Ana Casado, Auteur ; Borbala Hortobagyi, Auteur ; Erwan Roussel, Auteur Année de publication : 2018 Article en page(s) : pp 2427 - 2446 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] analyse comparative
[Termes IGN] barrage
[Termes IGN] bathymétrie
[Termes IGN] contour
[Termes IGN] image aérienne
[Termes IGN] interpolation linéaire
[Termes IGN] lac
[Termes IGN] modèle numérique de surface
[Termes IGN] modèle numérique de terrain
[Termes IGN] reconstruction 3D
[Termes IGN] structure-from-motionRésumé : (Auteur) The geometry of impounded surfaces is a key tool to reservoir storage management and projection. Yet topographic data and bathymetric surveys of average-aged reservoirs may be absent for many regions worldwide. This paper examines the potential of contour line interpolation (TOPO) and Structure from Motion (SfM) photogrammetry to reconstruct the topography of existing reservoirs prior to dam closure. The study centres on the Paso de las Piedras reservoir, Argentina, and assesses the accuracy and reliability of TOPO- and SfM- derived digital elevation models (DEMs) using different grid resolutions. All DEMs were of acceptable quality. However, different interpolation techniques produced different types of error, which increased (or decreased) with increasing (or decreasing) grid resolution as a function of their nature, and relative to the terrain complexity. In terms of DEM reliability to reproduce area–elevation relationships, processing-related disagreements between DEMs were markedly influenced by topography. Even though they produce intrinsic errors, it is concluded that both TOPO and SfM techniques hold great potential to reconstruct the bathymetry of existing reservoirs. For areas exhibiting similar terrain complexity, the implementation of one or another technique will depend ultimately on the need for preserving accurate elevation (TOPO) or topographic detail (SfM). Numéro de notice : A2018-527 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/13658816.2018.1511795 Date de publication en ligne : 05/09/2018 En ligne : https://doi.org/10.1080/13658816.2018.1511795 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91365
in International journal of geographical information science IJGIS > vol 32 n° 11-12 (November - December 2018) . - pp 2427 - 2446[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-2018061 RAB Revue Centre de documentation En réserve L003 Disponible A smooth curve as a fractal under the third definition / Ding Ma in Cartographica, vol 53 n° 3 (Fall 2018)
[article]
Titre : A smooth curve as a fractal under the third definition Type de document : Article/Communication Auteurs : Ding Ma, Auteur ; Bin Jiang, Auteur Année de publication : 2018 Article en page(s) : pp 203 - 210 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Cartographie
[Termes IGN] approche hiérarchique
[Termes IGN] courbe
[Termes IGN] lissage de courbe
[Termes IGN] logarithme
[Termes IGN] objet fractalRésumé : (Auteur) It is commonly believed in the literature that smooth curves, such as circles, are not fractal, and only non-smooth curves, such as coastlines, are fractal. However, this article demonstrates that a smooth curve can be fractal, under a new, relaxed, third definition of fractal – a set or pattern is fractal if the scaling of far more small things than large ones recurs at least twice. The scaling can be rephrased as a hierarchy, consisting of numerous smallest, a very few largest, and some in between the smallest and the largest. The logarithmic spiral, as a smooth curve, is apparently fractal because it bears the self-similarity property, or the scaling of far more small squares than large ones recurs multiple times, or the scaling of far more small bends than large ones recurs multiple times. A half-circle or half-ellipse and the UK coastline (before or after smooth processing) are fractal if the scaling of far more small bends than large ones recurs at least twice. Numéro de notice : A2018-483 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.3138/cart.53.3.2017-0032 Date de publication en ligne : 01/10/2018 En ligne : https://doi.org/10.3138/cart.53.3.2017-0032 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91208
in Cartographica > vol 53 n° 3 (Fall 2018) . - pp 203 - 210[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 031-2018031 SL Revue Centre de documentation Revues en salle Disponible Progressive registration of image features and 3D vector lines for orientation modelling / Wen-Chi Chang in Photogrammetric record, vol 33 n° 161 (March 2018)PermalinkPermalinkRegistration of images to Lidar and GIS data without establishing explicit correspondences / Gabor Barsai in Photogrammetric Engineering & Remote Sensing, PERS, vol 83 n° 10 (October 2017)PermalinkOn the visibility locations for continuous curves / Sarang Joshi in Computers and graphics, vol 66 (August 2017)PermalinkForce-directed layout of origin-destination flow maps / Bernhard Jenny in International journal of geographical information science IJGIS, vol 31 n° 7-8 (July - August 2017)PermalinkAbsolute orientation based on line coordinates / Qing H. Sheng in Photogrammetric record, vol 32 n° 157 (March - May 2017)PermalinkPermalinkPermalinkmR-V: Line simplification through mnemonic rasterization / Emmanuel Stefanakis in Geomatica, vol 70 n° 4 (December 2016)PermalinkFourier-based multi-scale representation and progressive transmission of cartographic curves on the internet / Pengcheng Liu in Cartography and Geographic Information Science, vol 43 n° 5 (November 2016)Permalink