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Clustering with obstacles for geographical data mining / V. Estivill-Castro in ISPRS Journal of photogrammetry and remote sensing, vol 59 n° 1-2 (August 2004 - April 2005)
[article]
Titre : Clustering with obstacles for geographical data mining Type de document : Article/Communication Auteurs : V. Estivill-Castro, Auteur ; I. Lee, Auteur Année de publication : 2004 Article en page(s) : pp 21 - 34 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] analyse de groupement
[Termes IGN] base de données localisées
[Termes IGN] classification barycentrique
[Termes IGN] classification par la distance de Mahalanobis
[Termes IGN] distance euclidienne
[Termes IGN] exploration de données géographiques
[Termes IGN] système d'information géographique
[Termes IGN] triangulation de DelaunayRésumé : (Auteur) Clustering algorithms typically use the Euclidean distance. However, spatial proximity is dependent on obstacles, caused by related information in other layers of the spatial database. We present a clustering algorithm suitable for large spatial databases with obstacles. The algorithm is free of user-supplied arguments and incorporates global and local variations. The algorithm detects clusters in complex scenarios and successfully supports association analysis between layers. All this occurs within O(n log n+[s + t] log n) expected time, where n is the number of points, s is the number of line segments that determine the obstacles and t is the number of Delaunay edges intersecting the obstacles. Copyright ISPRS Numéro de notice : A2004-312 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2003.12.003 En ligne : https://doi.org/10.1016/j.isprsjprs.2003.12.003 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26839
in ISPRS Journal of photogrammetry and remote sensing > vol 59 n° 1-2 (August 2004 - April 2005) . - pp 21 - 34[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-04031 RAB Revue Centre de documentation En réserve L003 Disponible A land cover classification product over France at 1 km resolution using Spot4-Vegetation data / K.S. Han in Remote sensing of environment, vol 92 n° 1 (15 July 2004)
[article]
Titre : A land cover classification product over France at 1 km resolution using Spot4-Vegetation data Type de document : Article/Communication Auteurs : K.S. Han, Auteur ; J.L. Champeaux, Auteur ; Jean-Louis Roujean, Auteur Année de publication : 2004 Article en page(s) : pp 52 - 66 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] analyse comparative
[Termes IGN] analyse de groupement
[Termes IGN] base de données d'occupation du sol
[Termes IGN] Corine Land Cover
[Termes IGN] image NOAA-AVHRR
[Termes IGN] image SPOT-Végétation
[Termes IGN] image Terra-MODIS
[Termes IGN] occupation du solRésumé : (Auteur) The present study focuses on the development of a new land cover classification product over France at 1 km resolution. It is based on data sets from the Earth observing system SPOT4/VEGETATION. The satellite measurements are aimed at supporting regional efforts to set up global mosaics on new land cover products. They have been acquired in the frame of the Global Land Cover 2000 project. The instrument design relies on advanced technology, which leads to an improved radiometric and geometric resolution data. Such characteristics allow taking full benefit of the daily repetitiveness of the VEGETATION wide field-of-view sensor without the drawback of a variable pixel size on the image edge. Several physical processing steps are successively operated to the images on a per-pixel basis to remove detector blindness, to filter cloud contamination, and finally to correct both atmospheric and surface anisotropy effects. A new thematic map using the K-means clustering method has been built. First, the results of the satellite-based land cover classification has been successfully compared with the Coordination of Information on the Environment (CORINE) database which serves as a reference to appraise the reliability of the study. Then, it has been inter-compared with land cover products derived from MODIS and AVHRR sensors. For this, an aggregative scheme particularly focused on major land units (forest, grassland, cropland) adopted in order to yield a whole mapping at the same geographic projection and space resolution. The discrepancies between maps enhance the quality of the proposed product, thanks to the use of advanced data processing and a more appropriate method. Numéro de notice : A2004-298 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2004.05.005 En ligne : https://doi.org/10.1016/j.rse.2004.05.005 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26825
in Remote sensing of environment > vol 92 n° 1 (15 July 2004) . - pp 52 - 66[article]Intra-urban location and clustering of road accidents using GIS: a Belgian example / T. Steenberghen in International journal of geographical information science IJGIS, vol 18 n° 2 (march 2004)
[article]
Titre : Intra-urban location and clustering of road accidents using GIS: a Belgian example Type de document : Article/Communication Auteurs : T. Steenberghen, Auteur ; Isabelle Thomas, Auteur ; et al., Auteur Année de publication : 2004 Article en page(s) : pp 169 - 181 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes d'information géographique
[Termes IGN] accident de la route
[Termes IGN] agrégation de données
[Termes IGN] analyse comparative
[Termes IGN] analyse de groupement
[Termes IGN] base de données urbaines
[Termes IGN] Belgique
[Termes IGN] flux
[Termes IGN] géocodage
[Termes IGN] réseau routier
[Termes IGN] sécurité routière
[Termes IGN] segmentation dynamique
[Termes IGN] système d'information géographique
[Termes IGN] trafic routier
[Termes IGN] trafic urbain
[Termes IGN] zone urbaineRésumé : (Auteur) This paper aims to show the usefulness of GIS and point pattern techniques for defining road-accident black zones within urban agglomerations. The location of road accidents is based on dynamic segmentation, address geocoding and intersection identification. One-dimensional (line) and two-dimensional (area) clustering techniques for road accidents are compared. Advantages and drawbacks are discussed in relation to network and traffic characteristics. Linear spatial clustering techniques appear to be better suited when traffic flows can be clearly identified along certain routes. For dense road networks with diffuse traffic patterns, two-dimensional techniques make it possible to identify accident-prone areas. The operationality of the techniques is illustrated by showing the impact of traffic-calming measures on the location and type of accidents in one Belgian town (Mechelen). Numéro de notice : A2004-041 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article DOI : 10.1080/13658810310001629619 En ligne : https://doi.org/10.1080/13658810310001629619 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26569
in International journal of geographical information science IJGIS > vol 18 n° 2 (march 2004) . - pp 169 - 181[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-04021 RAB Revue Centre de documentation En réserve L003 Disponible Approaches to fractional land cover and continuous field mapping: a comparative assessment over the BOREAS [BOReal Ecosystem Atmosphere Study] study region / R. Fernandes in Remote sensing of environment, vol 89 n° 2 (30/01/2004)
[article]
Titre : Approaches to fractional land cover and continuous field mapping: a comparative assessment over the BOREAS [BOReal Ecosystem Atmosphere Study] study region Type de document : Article/Communication Auteurs : R. Fernandes, Auteur ; R. Fraser, Auteur ; et al., Auteur Année de publication : 2004 Article en page(s) : pp 234 - 251 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse comparative
[Termes IGN] analyse de groupement
[Termes IGN] carte d'occupation du sol
[Termes IGN] classification par réseau neuronal
[Termes IGN] image Landsat-TM
[Termes IGN] image SPOT-Végétation
[Termes IGN] inversion
[Termes IGN] méthode des moindres carrés
[Termes IGN] précision infrapixellaire
[Termes IGN] régression multiple
[Termes IGN] tâche image d'un point
[Termes IGN] zone boréaleRésumé : (Auteur) Subpixel land cover mapping involves the estimation of surface properties using sensors whose spatial sampling is coarse enough to produce mixtures of the properties within each pixel. This study evaluates five algorithms for mapping subpixel land cover fractions and continuous fields of vegetation properties within the BOREAS study area. The algorithms include a conventional "hard", perpixel classifier, a neural network, a clustering/look-up-table approach, multivariate regression, and linear least squares inversion. A land cover map prepared using a Landsat TM mosaic was adopted as the source of fine scale calibration and validation data. Coarse scale mixtures of five basic land cover classes and continuous vegetation fields, both corresponding to the field of view of SPOT-VEGETATION imagery (1.15-km pixel size), were synthesised from the TM mosaic using a modelled point spread function. Two measures of land cover distribution were used. fractions of fine scale land cover categories and continuous fields of vegetation structural characteristics. The subpixel algorithms were applied using both proximate ( 400 km) separation between training and validation regions. "Hard" classification performed poorly in estimating proportions or continuous fields. The neural network, look-up-table and multivariate regression algorithms produced good matches of spatial patterns and regional land cover composition for the proximate treatment. However, all three methods exhibited substantial biases with the distant treatment due to the characteristics of the training data. Linear least squares inversion offers a relatively unbiased but less precise alternative for subpixel proportion and fraction mapping as it avoids calibration to the a priori distribution of land cover in the training data. In general, a combination of multivariate regression for proximate training data and linear least squares inversion for distant training data resulted in woody fraction estimates within 20% of the Landsat TM classification-based estimates. Numéro de notice : A2004-026 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2002.06.006 En ligne : https://doi.org/10.1016/j.rse.2002.06.006 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26554
in Remote sensing of environment > vol 89 n° 2 (30/01/2004) . - pp 234 - 251[article]Evaluation of speckle noise MAP filtering algorithms applied to SAR images / F.N.S. Medeiros in International Journal of Remote Sensing IJRS, vol 24 n° 24 (December 2003)
[article]
Titre : Evaluation of speckle noise MAP filtering algorithms applied to SAR images Type de document : Article/Communication Auteurs : F.N.S. Medeiros, Auteur ; N.D.A. Mascarenhas, Auteur ; L.F. Costa, Auteur Année de publication : 2003 Article en page(s) : pp 5197 - 5218 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] analyse de groupement
[Termes IGN] chatoiement
[Termes IGN] filtrage du rayonnement
[Termes IGN] filtre de déchatoiement
[Termes IGN] limite de résolution radiométrique
[Termes IGN] radar à antenne synthétique
[Termes IGN] transformation de HoughRésumé : (Auteur) This work proposes new speckle reduction filters for multilook, amplitude detected Synthetic Aperture Radar (SAR) images based on the maximum a posteriori (MAP) approach and compares their performance. The new filters use an adaptive approach based on the one-dimensional k-means clustering algorithm over the variance ratio and also a regiongrowing procedure. The trade-off between the loss of radiometric resolution and edge preservation is evaluated in the filtered images. In order to obtain quantitative measures of the speckle reduction and of the edge blurring, we used some parameters such as the classical equivalent number of looks and the Hough transform. Experiments have been carried out with natural images corrupted with synthetic speckle noise following the Rayleigh and square root of gamma distributions and with real SAR images. Numéro de notice : A2003-341 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/0143116031000115148 En ligne : https://doi.org/10.1080/0143116031000115148 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=22636
in International Journal of Remote Sensing IJRS > vol 24 n° 24 (December 2003) . - pp 5197 - 5218[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 080-03241 RAB Revue Centre de documentation En réserve L003 Exclu du prêt A comparison of vector and raster GIS methods for calculating landscape metrics used in environmental assessments / T.G. Wade in Photogrammetric Engineering & Remote Sensing, PERS, vol 69 n° 12 (December 2003)PermalinkPrincipal-components-based display strategy for spectral imagery / J.S. Tyo in IEEE Transactions on geoscience and remote sensing, vol 41 n° 3 (March 2003)PermalinkLandscape dynamics of the spread of sudden oak death / M. Kelly in Photogrammetric Engineering & Remote Sensing, PERS, vol 68 n° 10 (October 2002)PermalinkLarge-area land-cover mapping through scene-based classification compositing / B. Guindon in Photogrammetric Engineering & Remote Sensing, PERS, vol 68 n° 6 (June 2002)PermalinkA synergic automatic clustering technique (syneract) for multispectral image analysis / K.Y. Huang in Photogrammetric Engineering & Remote Sensing, PERS, vol 68 n° 1 (January 2002)PermalinkDetection of urban structures in SAR images by robust fuzzy clustering algorithms: the example of street tracking / F. Dell'acqua in IEEE Transactions on geoscience and remote sensing, vol 39 n° 10 (October 2001)PermalinkClustering to improve matched filter detection of weak gas plumes in hyperspectral thermal imagery / C.C. Funk in IEEE Transactions on geoscience and remote sensing, vol 39 n° 7 (July 2001)PermalinkGraph-based representations in pattern recognition, GbR'99 / Walter G. Kropatsch (1999)PermalinkSegmentierung und Interpretation digitaler Bilder mit Markoff-Zufallsfeldern / J. Klonowski (1999)PermalinkSDH 98 Proceedings, 8th international symposium on spatial data handling, Vancouver, July 11 - 15, 1998 / Thomas K. Poiker (1998)Permalink