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Assuring the quality of VGI on land use and land cover: experiences and learnings from the LandSense project / Giles M. Foody in Geo-spatial Information Science, vol 26 n° inconnu ([01/08/2023])
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Titre : Assuring the quality of VGI on land use and land cover: experiences and learnings from the LandSense project Type de document : Article/Communication Auteurs : Giles M. Foody, Auteur ; Gavin Long, Auteur ; Michael Schultz, Auteur ; Ana-Maria Olteanu-Raimond , Auteur
Année de publication : 2023 Projets : Landsense / Raimond, Ana-Maria Article en page(s) : n° 2100285 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] assurance qualité
[Termes IGN] données localisées des bénévoles
[Termes IGN] occupation du sol
[Termes IGN] qualité des données
[Termes IGN] utilisation du solRésumé : (auteur) The potential of citizens as a source of geographical information has been recognized for many years. Such activity has grown recently due to the proliferation of inexpensive location aware devices and an ability to share data over the internet. Recently, a series of major projects, often cast as citizen observatories, have helped explore and develop this potential for a wide range of applications. Here, some of the experiences and learnings gained from part of one such project, which aimed to further the role of citizen science within Earth observation and help address environmental challenges, LandSense, are shared. The key focus is on quality assurance of citizen generated data on land use and land cover especially to support analyses of remotely sensed data and products. Particular focus is directed to quality assurance checks on photographic image quality, privacy, polygon overlap, positional accuracy and offset, contributor agreement, and categorical accuracy. The discussion aims to provide good practice advice to aid future studies and help fulfil the full potential of citizens as a source of volunteered geographical information (VGI). Numéro de notice : A2023-081 Affiliation des auteurs : UGE-LASTIG+Ext (2020- ) Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10095020.2022.2100285 Date de publication en ligne : 21/07/2022 En ligne : https://doi.org/10.1080/10095020.2022.2100285 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101337
in Geo-spatial Information Science > vol 26 n° inconnu [01/08/2023] . - n° 2100285[article]Quality assessment of volunteered geographic information for outdoor activities: an analysis of OpenStreetMap data for names of peaks in Japan / Jun Yamashita in Geo-spatial Information Science, vol 26 n° inconnu ([01/08/2023])
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Titre : Quality assessment of volunteered geographic information for outdoor activities: an analysis of OpenStreetMap data for names of peaks in Japan Type de document : Article/Communication Auteurs : Jun Yamashita, Auteur ; Toshikazu Seto, Auteur ; Nobusuke Iwasaki, Auteur ; Yuichiro Nishimura, Auteur Année de publication : 2023 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] données localisées des bénévoles
[Termes IGN] Japon
[Termes IGN] montagne
[Termes IGN] OpenStreetMap
[Termes IGN] oronymie
[Termes IGN] qualité des donnéesRésumé : (auteur) Geographical studies of outdoor activities have increased in recent years with the rise in popularity of these activities worldwide, including in Japan. Volunteered geographic information (VGI) is a key tool for organizing outdoor activities as it offers a means to determine the locational information and names of places. To evaluate the quality of VGI, geospatial data generated by land survey agencies and other VGI are often utilized as reference data. However, since these reference data may not be available, other methods are necessary to assure the quality of VGI. In this study, we examined five trust indicators based on the inherent characteristics of VGI through an empirical case study. We used mountain names extracted from OpenStreetMap in Japan as data because there were almost no other VGI in the vicinity. As a result, we isolated three trust indicators, namely versions, users, and tag corrections, to examine the thematic accuracy of VGI because these were the only statistically significant indicators. However, we found that the prediction rate of thematic accuracy was very low. To improve thematic accuracy, this study recommends using the most accurate versions, applying correctly given tags, and considering the motivations and characteristics of the VGI contributors. Numéro de notice : A2022-611 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10095020.2022.2085188 Date de publication en ligne : 01/07/2022 En ligne : https://doi.org/10.1080/10095020.2022.2085188 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101365
in Geo-spatial Information Science > vol 26 n° inconnu [01/08/2023][article]Resilience of Pyrenean forests after recurrent historical deforestations / Valenti Rull in Forests, vol 14 n° 3 (March 2023)
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Titre : Resilience of Pyrenean forests after recurrent historical deforestations Type de document : Article/Communication Auteurs : Valenti Rull, Auteur ; Teresa Vegas-Vilarrúbia, Auteur Année de publication : 2023 Article en page(s) : n° 567 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] déboisement
[Termes IGN] forêt méditerranéenne
[Termes IGN] histoire
[Termes IGN] historique des données
[Termes IGN] régénération (sylviculture)
[Termes IGN] résilience écologique
[Vedettes matières IGN] Ecologie forestièreRésumé : (auteur) The long-term resilience of Pyrenean forests in the face of historical anthropogenic clearing remains largely unknown. In this paper, a high-resolution (decadal to subdecadal) paleoecological study of mid-elevation Pyrenean forests is presented that encompasses the last two millennia. This long-term record was obtained after sediment coring, dating (varve counting) and pollen analysis of annually laminated (varved) sediments from Lake Montcortès, situated at 1027 m elevation, in the transition between the Mediterranean and montane forest belts. This allowed the definition of three major deforestation/recovery cycles during the Roman, Medieval and Modern times. Each DR cycle is characterized considering three different levels: overall forest trends, forest type and individual taxa. Overall, the studied forests exhibited high resilience, as they recovered almost completely after each deforestation event (bulk resilience). The critical point of no return (tipping point) beyond which forests would have irreversibly disappeared from the region was never reached, even after deforestation magnitudes above 60%. The different forest types identified (conifer, sclerophyll and deciduous) persisted over time, showing similar heterogeneous patterns with minor spatial reorganizations (mosaic resilience). Individually, the main forest taxa underwent minor variations in their relative abundances, always within the same attraction domains (community resilience). The high levels of resilience documented in these Pyrenean forests are attributed to the action of metapopulation and metacommunity processes and mechanisms in a highly dynamic patchy environment. Conservation actions should be focused on the maintenance of these spatial patterns and the associated ecological dynamics. Numéro de notice : A2023-166 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.3390/f14030567 Date de publication en ligne : 13/03/2023 En ligne : https://doi.org/10.3390/f14030567 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102903
in Forests > vol 14 n° 3 (March 2023) . - n° 567[article]Estimation of lidar-based gridded DEM uncertainty with varying terrain roughness and point density / Luyen K. Bui in ISPRS Open Journal of Photogrammetry and Remote Sensing, vol 7 (January 2023)
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Titre : Estimation of lidar-based gridded DEM uncertainty with varying terrain roughness and point density Type de document : Article/Communication Auteurs : Luyen K. Bui, Auteur ; Craig L. Glennie, Auteur Année de publication : 2023 Article en page(s) : n° 100028 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] Alaska (Etats-Unis)
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] Hawaii (Etats-Unis)
[Termes IGN] incertitude des données
[Termes IGN] interpolation
[Termes IGN] modèle numérique de surface
[Termes IGN] semis de points
[Termes IGN] Triangulated Irregular NetworkRésumé : (auteur) Light detection and ranging (lidar) scanning systems can be used to provide a point cloud with high quality and point density. Gridded digital elevation models (DEMs) interpolated from laser scanning point clouds are widely used due to their convenience, however, DEM uncertainty is rarely provided. This paper proposes an end-to-end workflow to quantify the uncertainty (i.e., standard deviation) of a gridded lidar-derived DEM. A benefit of the proposed approach is that it does not require independent validation data measured by alternative means. The input point cloud requires per point uncertainty which is derived from lidar system observational uncertainty. The propagated uncertainty caused by interpolation is then derived by the general law of propagation of variances (GLOPOV) with simultaneous consideration of both horizontal and vertical point cloud uncertainties. Finally, the interpolated uncertainty is then scaled by point density and a measure of terrain roughness to arrive at the final gridded DEM uncertainty. The proposed approach is tested with two lidar datasets measured in Waikoloa, Hawaii, and Sitka, Alaska. Triangulated irregular network (TIN) interpolation is chosen as the representative gridding approach. The results indicate estimated terrain roughness/point density scale factors ranging between 1 (in flat areas) and 7.6 (in high roughness areas), with a mean value of 2.3 for the Waikoloa dataset and between 1 and 9.2 with a mean value of 1.2 for the Sitka dataset. As a result, the final gridded DEM uncertainties are estimated between 0.059 m and 0.677 m with a mean value of 0.164 m for the Waikoloa dataset and between 0.059 m and 1.723 m with a mean value of 0.097 m for the Sitka dataset. Numéro de notice : A2023-120 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1016/j.ophoto.2022.100028 Date de publication en ligne : 17/12/2023 En ligne : https://doi.org/10.1016/j.ophoto.2022.100028 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102494
in ISPRS Open Journal of Photogrammetry and Remote Sensing > vol 7 (January 2023) . - n° 100028[article]Precise orbit determination for BDS-3 GEO satellites enhanced by intersatellite links / Xiaojie Li in GPS solutions, vol 27 n° 1 (January 2023)
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Titre : Precise orbit determination for BDS-3 GEO satellites enhanced by intersatellite links Type de document : Article/Communication Auteurs : Xiaojie Li, Auteur ; Xiaogong Hu, Auteur ; Rui Guo, Auteur ; et al., Auteur Année de publication : 2023 Article en page(s) : n° 8 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Techniques orbitales
[Termes IGN] constellation BeiDou
[Termes IGN] décalage d'horloge
[Termes IGN] orbite géostationnaire
[Termes IGN] orbite précise
[Termes IGN] orbitographie
[Termes IGN] qualité des donnéesRésumé : (auteur) Geostationary orbit (GEO) satellites are an integral part of the BeiDou Navigation Satellite System (BDS). Precise orbit determination (POD) for GEO satellites is difficult due to their geostationary characteristics. The orbit determination accuracy that can be achieved based on regional tracking stations in China cannot satisfy high-precision service requirements. The third generation of BDS (BDS-3) is the first global navigation satellite system that synergistically uses regional monitoring stations and global intersatellite links (ISLs) to realize global service. In this study, the quality of ISL data is analyzed based on the residuals of the intersatellite clock offset and the observed-minus-computed residuals of the ISL data. The orbit determination accuracy is assessed based on the observation residuals, the multiday consistency of the ISL time delays, overlapping orbit comparison, the user equivalent range error (UERE), and the accuracy of the clock offset. The results show that the ISL measurement noise for the GEO satellites is 3 cm, and the multiday consistency accuracy of the ISL time delay is better than 0.07 ns. Compared to the satellite-to-ground link (SGL)-based orbit determination method, the root mean square (RMS) three-dimensional (3D) position error of the overlapping orbit differences (OODs) is improved from 1.11 to 0.22 m with the combined SGL- and ISL-based method. Simultaneously, the UERE improves from 0.57 to 0.19 m, and the accuracy of the satellite clock offset improves from 1.09 to 0.61 ns. Numéro de notice : A2023-001 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s10291-022-01330-3 Date de publication en ligne : 14/10/2022 En ligne : https://doi.org/10.1007/s10291-022-01330-3 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101870
in GPS solutions > vol 27 n° 1 (January 2023) . - n° 8[article]An automated approach for clipping geographic data before projection that maintains data integrity and minimizes distortion for virtually any projection method / Jim Graham in Cartographica, Vol 57 n° 4 (December 2022)
PermalinkComparison of methods for the automatic classification of forest habitat types in the Southern Alps : Application to ecological data from the French national forest inventory / Charlotte Labit in Biodiversity & Conservation, vol 31 n° 13-14 (December 2022)
PermalinkLinkClimate: An interoperable knowledge graph platform for climate data / Jiantao Wu in Computers & geosciences, vol 169 (December 2022)
PermalinkSemantic integration of OpenStreetMap and CityGML with formal concept analysis / Somayeh Ahmadian in Transactions in GIS, vol 26 n° 8 (December 2022)
PermalinkThere’s no best model! Addressing limitations of land-use scenario modelling through multi-model ensembles / Richard J. Hewitt in International journal of geographical information science IJGIS, vol 36 n° 12 (December 2022)
PermalinkGraph neural networks with constraints of environmental consistency for landslide susceptibility evaluation / Haowei Zeng in International journal of geographical information science IJGIS, vol 36 n° 11 (November 2022)
PermalinkAn estimation method to reduce complete and partial nonresponse bias in forest inventory / James A. Westfall in European Journal of Forest Research, vol 141 n° 5 (October 2022)
Permalink3D LiDAR aided GNSS/INS integration fault detection, localization and integrity assessment in urban canyons / Zhipeng Wang in Remote sensing, vol 14 n° 18 (September-2 2022)
PermalinkA general model for creating robust choropleth maps / Wangshu Mu in Computers, Environment and Urban Systems, vol 96 (September 2022)
PermalinkA geographical and content-based approach to prioritize relevant and reliable tweets for emergency management / A. Marcela Suarez in Cartography and Geographic Information Science, Vol 49 n° 5 (September 2022)
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