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contenu dans Agile 2004, 7th Agile Conference on Geographic Information Science, Heraklion (Greece), 29 April - 1 May 2004 / Fred Toppen (2004)
Titre : A prototype cross-border GML data service Type de document : Article/Communication Auteurs : L. Lehto, Auteur ; Tapani Sarjakoski, Auteur ; A. Hvas, Auteur ; et al., Auteur Editeur : Association of Geographic Information Laboratories in Europe AGILE Année de publication : 2004 Conférence : AGILE 2004, 7th international conference on geographic information science 29/04/2004 01/05/2004 Heraklion Grèce Open access proceedings Importance : pp 361 - 367 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Information géographique
[Termes IGN] GML
[Termes IGN] intégration de données
[Termes IGN] service de géoinformation
[Termes IGN] Web Feature Service
[Termes IGN] XSLTRésumé : (Auteur) Introduction of Geography Markup Language (GML) has opened new opportunities for creating integrated cross-border spatial data services. As an XML application, GML facilitates data integration by providing open, vendor-independent syntax for encoding spatial data. However, individual GML application schemas are inherently dependent on the local data content and thus vary from country to country. Those differences are also reflected in the corresponding Web Feature Service (WFS) queries. Consequently, a cross-border data service must support two-way transformations : those applied to incoming queries and those carried out on the delivered dataset. As the traffic in both directions is encoded in XML syntax, the same techniques can be employed in both tasks. In this paper, an approach based on a general-purpose XML processing tool, XSL Transformation (XSLT), is proposed and first experiences gained from a four-nation cross-border prototype service are described. Numéro de notice : C2004-011 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Communication DOI : sans En ligne : https://agile-online.org/images/conferences/2004/documents/papers/4-2-3_Lehto.pd [...] Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=65022 Comparisons of land cover and LAI estimates derived from ETM+ and MODIS for four sites in North America: a quality assessment of 2000/2001 provisional MODIS / W.B. Cohen in Remote sensing of environment, vol 88 n° 3 (15/12/2003)
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Titre : Comparisons of land cover and LAI estimates derived from ETM+ and MODIS for four sites in North America: a quality assessment of 2000/2001 provisional MODIS Type de document : Article/Communication Auteurs : W.B. Cohen, Auteur ; T.K. Maiersperger, Auteur ; S.T. Gower, Auteur ; S.W. Running, Auteur ; et al., Auteur Année de publication : 2003 Article en page(s) : pp 233 - 255 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] Advanced Very High Resolution Radiometer
[Termes IGN] agriculture
[Termes IGN] analyse comparative
[Termes IGN] forêt
[Termes IGN] image Landsat-ETM+
[Termes IGN] Leaf Area Index
[Termes IGN] Moderate Resolution Imaging Spectroradiometer
[Termes IGN] occupation du solRésumé : (Auteur) The MODIS land science team produces a number of standard products, including land cover and leaf area index (LAI). Critical to the success of MODIS and other sensor products is an independent evaluation of product quality. In that context, we describe a study using field data and Landsat ETM+ to map land cover and LAI at four 49-km2 sites in North America containing agricultural cropland (AGRO), prairie grassland (KONZ), boreal needleleaf forest, and temperate mixed forest. The purpose was to: (1) develop accurate maps of land cover, based on the MODIS IGBP (International Geosphere-Biosphere Programme) land cover classification scheme; (2) derive continuous surfaces of LAI that capture the mean and variability of the LAI field measurements; and (3) conduct initial MODIS validation exercises to assess the quality of early (i.e., provisional) MODIS products. ETM+ land cover maps varied in overall accuracy from 81% to 95%. The boreal forest was the most spatially complex, had the greatest number of classes, and the lowest accuracy. The intensive agricultural cropland had the simplest spatial structure, the least number of classes, and the highest overall accuracy. At each site, mapped LAI patterns generally followed patterns of land cover across the site. Predicted versus observed LAI indicated a high degree of correspondence between field-based measures and ETM+ predictions of LAI. Direct comparisons of ETM+ land cover maps with Collection 3 MODIS cover maps revealed several important distinctions and similarities. One obvious difference was associated with image/map resolution. ETM+ captured much of the spatial complexity of land cover at the sites. In contrast, the relatively coarse resolution of MODIS did not allow for that level of spatial detail. Over the extent of all sites, the greatest difference was an overprediction by MODIS of evergreen needleleaf forest cover at the boreal forest site, which consisted largely of open shrubland, woody savanna, and savanna. At the agricultural, temperate mixed forest, and prairie grassland sites, ETM+ and MODIS cover estimates were similar. Collection 3 MODISbased LAI estimates were considerably higher (up to 4m2 4m-2) than those based on ETM+ LAI at each site. There are numerous probable reasons for this, the most important being the algorithms' sensitivity to MODIS reflectance calibration, its use of a prelaunch AVHRR-based land cover map, and its apparent reliance on mainly red and near-IR reflectance. Samples of Collection 4 LAI products were examined and found to consist of significantly improved LAI predictions for KONZ, and to some extent for AGRO, but not for the other two sites. In this study, we demonstrate that MODIS reflectance data are highly correlated with LAI across three study sites, with relationships increasing in strength from 500 to 1000 m spatial resolution, when shortwave-infrared bands are included. Numéro de notice : A2003-345 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2003.06.006 En ligne : https://doi.org/10.1016/j.rse.2003.06.006 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26425
in Remote sensing of environment > vol 88 n° 3 (15/12/2003) . - pp 233 - 255[article]Efficient flow computation on massive grid terrain datasets / L. Arge in Geoinformatica, vol 7 n° 4 (December 2003)
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Titre : Efficient flow computation on massive grid terrain datasets Type de document : Article/Communication Auteurs : L. Arge, Auteur ; J.S. Chase, Auteur ; et al., Auteur Année de publication : 2003 Article en page(s) : pp 283 - 313 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Informatique
[Termes IGN] algorithmique
[Termes IGN] crue
[Termes IGN] données massives
[Termes IGN] écoulement des eaux
[Termes IGN] flux de données
[Termes IGN] géomorphologie
[Termes IGN] itinéraire
[Termes IGN] jeu de données localisées
[Termes IGN] mise à l'échelle
[Termes IGN] traitement de données localiséesRésumé : (Auteur) As detailed terrain data becomes available, GIS terrain applications target larger geographic areas at finer resolutions. Processing the massive datasets involved in such applications presents significant challenges to GIS systems and demands algorithms that are optimized for both data movement and computation. In this paper we present efficient algorithms for flow routing on massive grid terrain datasets, extending our previous work on flow accumulation. Our algorithms are developed in the framework of external memory algorithms and use I/0-techniques to achieve efficiency. We have implemented the algorithms in the Terraflow system, which is the first comprehensive terrain flow software system designed and optimized for massive data. We compare the performance of Terraflow with that of state-of-the-art commercial and opensource GIS systems. On large terrains, Terraflow outperforms existing systems by a factor of 2 to 1,000, and is capable of solving problems no system was previously able to solve. Numéro de notice : A2003-386 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article DOI : 10.1023/A:1025526421410 En ligne : https://doi.org/10.1023/A:1025526421410 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26466
in Geoinformatica > vol 7 n° 4 (December 2003) . - pp 283 - 313[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 057-03041 RAB Revue Centre de documentation En réserve L003 Disponible National report of France [to the Symposium of the IAG Subcommission for Europe (EUREF) held in Ponta Delgada , 5-8 June 2002] / Thierry Duquesnoy (01/12/2003)
contenu dans Report on the Symposium of the IAG Subcommission for Europe (EUREF) held in Ponta Delgada , 5-8 June 2002 & reports of the EUREF technical working group, EUREF publication n° 12 / Joao Agria Torres (2002)
Titre : National report of France [to the Symposium of the IAG Subcommission for Europe (EUREF) held in Ponta Delgada , 5-8 June 2002] Type de document : Article/Communication Auteurs : Thierry Duquesnoy , Auteur ; Bruno Garayt , Auteur ; et al., Auteur Editeur : Francfort sur le Main : Bundesamt für Kartographie und Geodäsie Année de publication : 01/12/2003 Conférence : EUREF 2002, Symposium of the AIG Subcommission for Europe 05/06/2002 08/06/2002 Ponta Delgada Portugal Open access proceedings Importance : pp 250 - 253 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] Institut géographique national (France)
[Termes IGN] réseau géodésique permanent français
[Termes IGN] station GPSRésumé : (documentaliste) Le rapport National de la France s'articule autour de la présentation du Réseau GPS Permanent (RGP), les centres opérationnels, et les activités relatives au système de référence ETRS89. Numéro de notice : C2002-015 Affiliation des auteurs : IGN (1940-2011) Thématique : POSITIONNEMENT Nature : Communication DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=64973 Polyline spatial join evaluation using raster approximation / L.G. Azevedo in Geoinformatica, vol 7 n° 4 (December 2003)
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Titre : Polyline spatial join evaluation using raster approximation Type de document : Article/Communication Auteurs : L.G. Azevedo, Auteur ; R.S. Monteiro, Auteur ; et al., Auteur Année de publication : 2003 Article en page(s) : pp 315 - 336 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géomatique
[Termes IGN] approximation
[Termes IGN] base de données localisées
[Termes IGN] filtre numérique
[Termes IGN] jointure spatiale
[Termes IGN] polyligne
[Termes IGN] requête spatialeRésumé : (Auteur) The main subject of spatial joins is polygons and polylines. Typical polygons and polylines can occupy several Kbytes. Since approximations use much less space, the processing of spatial joins can be greatly improved by the use of filters that reduce the need for examining the exact geometry of spatial objects in order to find the intersecting ones. Candidate pairs of approximations of spatial objects are evaluated using such filters. As a result, three possible sets of answers are identified: the positive one, composed of intersecting pairs; the negative one, composed of non-intersecting pairs; and the inconclusive one, composed of the remaining pairs of candidates. There are many approximations designed for polygons, but few are suitable for approximating polylines. This paper presents a spatial join processor based on the multi step query processor (MSQP) architecture [24]. We have developed a new polyfine approximation, named five color direction raster signature (5CDRS) [18]. It is used as the filter of MSQP's second step. The performance of the join processor and the approximation was evaluated with real world data sets. The results showed that our approach, when compared to others presented in the literature, reduced the inconclusive answers by 29% in the average. Consequently, the need for retrieving the representation of polylines and carrying out exact geometry tests is reduced by the same factor. As the exact geometry test is the most time consuming step, we have noticed that the overall time is also reduced by 38% in the average. The disk accesses are reduced by 41% in the average. Numéro de notice : A2003-387 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1023/A:1025569305481 En ligne : https://doi.org/10.1023/A:1025569305481 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26467
in Geoinformatica > vol 7 n° 4 (December 2003) . - pp 315 - 336[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 057-03041 RAB Revue Centre de documentation En réserve L003 Disponible Extending satellite remote sensing to local scales: land and water resources monitoring using high-resolution imagery / K.E. Sawaya in Remote sensing of environment, vol 88 n° 1 (30/11/2003)PermalinkIkonos spatial resolution and image interpretability characterization / R. Ryan in Remote sensing of environment, vol 88 n° 1 (30/11/2003)PermalinkMangrove research and coastal ecosystem studies with SPOT-4 HRVIR and TERRA ASTER in the Arabian Gulf / Hideo Saito in International Journal of Remote Sensing IJRS, vol 24 n° 21 (November 2003)PermalinkSpectral reflectance characterization of shallow lakes from the Brazilian pantanal wetlands with field and airborne hyperspectral data / L.S. Galvao in International Journal of Remote Sensing IJRS, vol 24 n° 21 (November 2003)PermalinkStudy of urban spatial patterns from SPOT panchromatic imagery using textural analysis / Qian Zhang in International Journal of Remote Sensing IJRS, vol 24 n° 21 (November 2003)PermalinkTowards an operational system for regional-scale rice yield estimation using a time-series of Radarsat ScanSAR images / Y. Li in International Journal of Remote Sensing IJRS, vol 24 n° 21 (November 2003)PermalinkA credit assignment approach to fusing classifiers of multiseason hyperspectral imagery / C. Bachmann in IEEE Transactions on geoscience and remote sensing, vol 41 n° 11 (November 2003)PermalinkA new maximum-likelihood joint segmentation technique for multitemporal SAR and multiband optical images / P. Lombardo in IEEE Transactions on geoscience and remote sensing, vol 41 n° 11 (November 2003)PermalinkOptimizing Indoor GPS performance: receiver frequency standards / L.D. Vittorini in GPS world, vol 14 n° 11 (November 2003)Permalinkvol 24 n° 20 - October 2003 - Geospatial knowledge processing for natural ressource management (Bulletin de International Journal of Remote Sensing IJRS) / Remote sensing and photogrammetry societyPermalink