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Safe separation distance score : a new metric for evaluating wildland firefighter safety zones using lidar / Michael J. Campbell in International journal of geographical information science IJGIS, vol 31 n° 7-8 (July - August 2017)
[article]
Titre : Safe separation distance score : a new metric for evaluating wildland firefighter safety zones using lidar Type de document : Article/Communication Auteurs : Michael J. Campbell, Auteur ; Philip E. Dennison, Auteur ; Bret W. Butler, Auteur Année de publication : 2017 Article en page(s) : pp 1448 - 1466 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] Californie (Etats-Unis)
[Termes IGN] carte thématique
[Termes IGN] distance euclidienne
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] hauteur des arbres
[Termes IGN] incendie de forêt
[Termes IGN] protection civile
[Termes IGN] topographie locale
[Termes IGN] zone tamponRésumé : (Ateur) Safety zones are areas where firefighters can retreat to in order to avoid bodily harm when threatened by burnover or entrapment from wildland fire. At present, safety zones are primarily designated by firefighting personnel as part of daily fire management activities. Though critical to safety zone assessment, the effectiveness of this approach is inherently limited by the individual firefighter’s or crew boss’s ability to accurately and consistently interpret vegetation conditions, topography, and spatial characteristics of potential safety zones (e.g. area and geometry of a forest clearing). In order to facilitate the safety zone identification and characterization process, this study introduces a new metric for safety zone evaluation: the Safe Separation Distance Score (SSDS). The SSDS is a numerical representation of the relative suitability of a given area as a safety zone according to its size, geometry, and surrounding vegetation height. This paper describes an algorithm for calculating pixel-based and polygon-based SSDS from lidar data. SSDS is calculated for every potential safety zone within a lidar dataset covering Tahoe National Forest, California, USA. A total of 2367 potential safety zones with an SSDS ≥1 were mapped, representing areas that are suitable for fires burning in low wind and low slope conditions. The highest SSDS calculated within the study area was 9.65, a score that represents suitability in the highest wind-steepest slope conditions. Potential safety zones were clustered in space, with areas in the northern and eastern portions of the National Forest containing an abundance of safety zones while areas to the south and west were completely devoid of them. SSDS can be calculated for potential safety zones in advance of firefighting, and can allow firefighters to carefully compare and select safety zones based on their location, terrain, and wind conditions. This technique shows promise as a standard method for objectively identifying and ranking safety zones on a spatial basis. Numéro de notice : A2017-308 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/13658816.2016.1270453 En ligne : http://dx.doi.org/10.1080/13658816.2016.1270453 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=85355
in International journal of geographical information science IJGIS > vol 31 n° 7-8 (July - August 2017) . - pp 1448 - 1466[article]Exemplaires(2)
Code-barres Cote Support Localisation Section Disponibilité 079-2017041 RAB Revue Centre de documentation En réserve L003 Disponible 079-2017042 RAB Revue Centre de documentation En réserve L003 Disponible An unsupervised two-stage clustering approach for forest structure classification based on X-band InSAR data — A case study in complex temperate forest stands / Sahra Abdullahi in International journal of applied Earth observation and geoinformation, vol 57 (May 2017)
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Titre : An unsupervised two-stage clustering approach for forest structure classification based on X-band InSAR data — A case study in complex temperate forest stands Type de document : Article/Communication Auteurs : Sahra Abdullahi, Auteur ; Mathias Schardt, Auteur ; Hans Pretzsch, Auteur Année de publication : 2017 Article en page(s) : pp 36 - 48 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] bande X
[Termes IGN] Bavière (Allemagne)
[Termes IGN] carte de Kohonen
[Termes IGN] classification barycentrique
[Termes IGN] classification non dirigée
[Termes IGN] distance euclidienne
[Termes IGN] forêt tempérée
[Termes IGN] image radar moirée
[Termes IGN] image TanDEM-X
[Termes IGN] image TerraSAR-X
[Termes IGN] interféromètrie par radar à antenne synthétique
[Termes IGN] structure d'un peuplement forestierRésumé : (auteur) Forest structure at stand level plays a key role for sustainable forest management, since the biodiversity, productivity, growth and stability of the forest can be positively influenced by managing its structural diversity. In contrast to field-based measurements, remote sensing techniques offer a cost-efficient opportunity to collect area-wide information about forest stand structure with high spatial and temporal resolution. Especially Interferometric Synthetic Aperture Radar (InSAR), which facilitates worldwide acquisition of 3d information independent from weather conditions and illumination, is convenient to capture forest stand structure. This study purposes an unsupervised two-stage clustering approach for forest structure classification based on height information derived from interferometric X-band SAR data which was performed in complex temperate forest stands of Traunstein forest (South Germany). In particular, a four dimensional input data set composed of first-order height statistics was non-linearly projected on a two-dimensional Self-Organizing Map, spatially ordered according to similarity (based on the Euclidean distance) in the first stage and classified using the k-means algorithm in the second stage. The study demonstrated that X-band InSAR data exhibits considerable capabilities for forest structure classification. Moreover, the unsupervised classification approach achieved meaningful and reasonable results by means of comparison to aerial imagery and LiDAR data. Numéro de notice : A2017-368 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.jag.2016.12.010 En ligne : https://doi.org/10.1016/j.jag.2016.12.010 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=85785
in International journal of applied Earth observation and geoinformation > vol 57 (May 2017) . - pp 36 - 48[article]Continuously generalizing buildings to built-up areas by aggregating and growing / Dongliang Peng (2017)
Titre : Continuously generalizing buildings to built-up areas by aggregating and growing Type de document : Article/Communication Auteurs : Dongliang Peng, Auteur ; Guillaume Touya , Auteur Editeur : New York [Etats-Unis] : Association for computing machinery ACM Année de publication : 2017 Conférence : UrbanGIS 2017, 3rd ACM SIGSPATIAL workshop 07/11/2017 10/11/2017 Redondo Beach Californie - Etats-Unis Proceedings ACM Langues : Anglais (eng) Descripteur : [Termes IGN] bati
[Termes IGN] construction
[Termes IGN] distance euclidienne
[Termes IGN] mise à l'échelle
[Termes IGN] polygone
[Termes IGN] simplification de contour
[Vedettes matières IGN] GénéralisationRésumé : (auteur) To enable smooth zooming, we propose a method to continuously generalize buildings from a given start map to a smaller-scale goal map, where there are only built-up area polygons instead of individual building polygons. We name the buildings on the start map original buildings. For an intermediate scale, we aggregate the original buildings that will become too close by adding bridges. We grow (bridged) original buildings based on buffering, and simplify the grown buildings. We take into account the shapes of the buildings both at the previous map and goal map to make sure that the buildings are always growing. The running time of our method is in O (n3), where n is the number of edges of all the original buildings.
The advantages of our method are as follows. First, the buildings grow continuously and, at the same time, are simplified. Second, right angles of buildings are preserved during growing: the merged buildings still look like buildings. Third, the distances between buildings are always larger than a specified threshold. We do a case study to show the performances of our method.Numéro de notice : C2017-027 Affiliation des auteurs : LASTIG COGIT+Ext (2012-2019) Thématique : GEOMATIQUE Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : 10.1145/3152178.3152188 Date de publication en ligne : 01/12/2017 En ligne : https://doi.org/10.1145/3152178.3152188 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=89290 Correction of terrestrial LiDAR intensity channel using Oren–Nayar reflectance model: An application to lithological differentiation / Dario Carrea in ISPRS Journal of photogrammetry and remote sensing, vol 113 (March 2016)
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Titre : Correction of terrestrial LiDAR intensity channel using Oren–Nayar reflectance model: An application to lithological differentiation Type de document : Article/Communication Auteurs : Dario Carrea, Auteur ; Antonio Abellan, Auteur ; Florian Humair, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 17 - 29 Note générale : bibliothèque Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] angle d'incidence
[Termes IGN] correction d'image
[Termes IGN] distance euclidienne
[Termes IGN] données lidar
[Termes IGN] réflectance du sol
[Termes IGN] semis de points
[Termes IGN] télémétrie laser terrestre
[Termes IGN] test de performanceRésumé : (auteur) Ground-based LiDAR has been traditionally used for surveying purposes via 3D point clouds. In addition to XYZ coordinates, an intensity value is also recorded by LiDAR devices. The intensity of the backscattered signal can be a significant source of information for various applications in geosciences.
Previous attempts to account for the scattering of the laser signal are usually modelled using a perfect diffuse reflection. Nevertheless, experience on natural outcrops shows that rock surfaces do not behave as perfect diffuse reflectors. The geometry (or relief) of the scanned surfaces plays a major role in the recorded intensity values.
Our study proposes a new terrestrial LiDAR intensity correction, which takes into consideration the range, the incidence angle and the geometry of the scanned surfaces. The proposed correction equation combines the classical radar equation for LiDAR with the bidirectional reflectance distribution function of the Oren–Nayar model. It is based on the idea that the surface geometry can be modelled by a relief of multiple micro-facets. This model is constrained by only one tuning parameter: the standard deviation of the slope angle distribution (σslope) of micro-facets.
Firstly, a series of tests have been carried out in laboratory conditions on a 2 m2 board covered by black/white matte paper (perfect diffuse reflector) and scanned at different ranges and incidence angles. Secondly, other tests were carried out on rock blocks of different lithologies and surface conditions. Those tests demonstrated that the non-perfect diffuse reflectance of rock surfaces can be practically handled by the proposed correction method.
Finally, the intensity correction method was applied to a real case study, with two scans of the carbonate rock outcrop of the Dents-du-Midi (Swiss Alps), to improve the lithological identification for geological mapping purposes. After correction, the intensity values are proportional to the intrinsic material reflectance and are independent from range, incidence angle and scanned surface geometry. The corrected intensity values significantly improve the material differentiation.Numéro de notice : A2016-532 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2015.12.004 En ligne : https://doi.org/10.1016/j.isprsjprs.2015.12.004 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81616
in ISPRS Journal of photogrammetry and remote sensing > vol 113 (March 2016) . - pp 17 - 29[article]Impact de l’anisotropie du milieu dans les études de profilage géographique / Marie Trotta in Revue internationale de géomatique, vol 25 n° 4 (octobre - décembre 2015)
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Titre : Impact de l’anisotropie du milieu dans les études de profilage géographique Type de document : Article/Communication Auteurs : Marie Trotta, Auteur ; Cécile Deprez, Auteur ; Jean-Paul Donnay, Auteur Année de publication : 2015 Article en page(s) : pp 561 - 579 Note générale : Bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] anisotropie
[Termes IGN] Belgique
[Termes IGN] densité d'information
[Termes IGN] distance euclidienne
[Termes IGN] données statistiques
[Termes IGN] origine - destination
[Termes IGN] répartition géographique
[Termes IGN] réseau routier
[Termes IGN] zone géographiqueRésumé : (auteur) Cet article a pour objectif d’évaluer le biais introduit par l’usage de la distance euclidienne dans le cadre d’analyses de profilage géographique. Elle procède par une comparaison des distances routières et euclidiennes calculées sur près de 1 000 couples d’origines-destinations (sites de crimes – point d’ancrage du criminel) issus de la base de données de la police fédérale belge. Les comparaisons sont différenciées selon la densité du réseau de voirie (milieux rural et urbanisé) et les paramètres statistiques des distributions résultantes sont exploités dans l’application du modèle de décroissance avec la distance, principal outil de profilage géographique. Numéro de notice : A2015-927 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.3166/RIG.25.561-579 Date de publication en ligne : 24/06/2016 En ligne : https://doi.org/10.3166/RIG.25.561-579 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79729
in Revue internationale de géomatique > vol 25 n° 4 (octobre - décembre 2015) . - pp 561 - 579[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 047-2015041 RAB Revue Centre de documentation En réserve L003 Disponible An alternative method to constructing time cartograms for the visual representation of scheduled movement data / Rehmat Ullah in Journal of maps, vol 11 n° 4 ([01/08/2015])PermalinkVery high resolution image matching based on local features and k-means clustering / Amin Sedaghat in Photogrammetric record, vol 30 n° 150 (June - August 2015)PermalinkDetection of abrupt changes in spatial relationships in video sequences / Abdalbassir Abou-Elailah (2015)PermalinkSpectral-angle-based Laplacian Eigenmaps for non linear dimensionality reduction of hyperspectral imagery / L. Yan in Photogrammetric Engineering & Remote Sensing, PERS, vol 80 n° 9 (September 2014)PermalinkA fully constrained linear spectral unmixing algorithm based on distance geometry / Hanye Pu in IEEE Transactions on geoscience and remote sensing, vol 52 n° 2 (February 2014)PermalinkUrban network analysis: Centrality, sinuosity and shortcut detection / Theophile Emmanouilidis in Revue internationale de géomatique, vol 23 n° 3 - 4 (septembre 2013 - février 2014)PermalinkDevelopment of a network-based method for unmixing of hyperspectral data / V. Karathanassi in IEEE Transactions on geoscience and remote sensing, vol 50 n° 3 (March 2012)PermalinkComputational method for the point cluster analysis on networks / K. Sugihara in Geoinformatica, vol 15 n° 1 (January 2011)PermalinkQuality assessment of 3D building data / Devrim Akca in Photogrammetric record, vol 25 n° 132 (December 2010 - February 2011)PermalinkUsing clustering methods in geospatial information systems / X. Wang in Geomatica, vol 64 n° 3 (September 2010)Permalink