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Adjustment of observation accuracy harmonisation parameters in optimising the network’s reliability / Edward Nowak in Reports on geodesy and geoinformatics, vol 105 n° 1 (June 2018)
[article]
Titre : Adjustment of observation accuracy harmonisation parameters in optimising the network’s reliability Type de document : Article/Communication Auteurs : Edward Nowak, Auteur ; Waldemar Odziemczyk, Auteur Année de publication : 2018 Article en page(s) : pp 53 – 59 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] fiabilité des données
[Termes IGN] harmonisation des donnéesRésumé : (Auteur) Appropriate precision and low cost are the basic conditions that have to be fulfilled by a project of a geodetic network. Reliability, translating into the ability to detect gross errors in the observations and higher certainty of the obtained point position, is an important network characteristic. The principal way to provide appropriate network reliability is to acquire a suitably large number of redundant observations. Optimisation of the observation accuracy harmonisation procedure allowing for the acquisition of an appropriate level of reliability through modification of the observation a priori standard deviations is the focus of this study. Parameterisation of the accuracy harmonisation is proposed. Furthermore, the influence of the individual parameter operation on the effectiveness of the harmonisation procedure is tested. Based on the results of the tests an optimal set of harmonisation parameters which guarantees the maximal efficiency of the harmonisation algorithm is proposed. Numéro de notice : A2018-441 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.2478/rgg-2018-0006 Date de publication en ligne : 17/07/2018 En ligne : https://doi.org/10.2478/rgg-2018-0006 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91012
in Reports on geodesy and geoinformatics > vol 105 n° 1 (June 2018) . - pp 53 – 59[article]Influence of sample size on automatic positional accuracy assessment methods for urban areas / Francisco Javier Ariza-López in ISPRS International journal of geo-information, vol 7 n° 6 (June 2018)
[article]
Titre : Influence of sample size on automatic positional accuracy assessment methods for urban areas Type de document : Article/Communication Auteurs : Francisco Javier Ariza-López, Auteur ; Juan J. Ruiz-Lendínez, Auteur ; Manuel A. Ureña-Cámara, Auteur Année de publication : 2018 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] base de données urbaines
[Termes IGN] distance de Kolmogorov-Smirnov
[Termes IGN] échantillon
[Termes IGN] polygone
[Termes IGN] précision de localisation
[Termes IGN] précision planimétrique
[Termes IGN] qualité des données
[Termes IGN] zone urbaineRésumé : (Auteur) In recent years, new approaches aimed to increase the automation level of positional accuracy assessment processes for spatial data have been developed. However, in such cases, an aspect as significant as sample size has not yet been addressed. In this paper, we study the influence of sample size when estimating the planimetric positional accuracy of urban databases by means of an automatic assessment using polygon-based methodology. Our study is based on a simulation process, which extracts pairs of homologous polygons from the assessed and reference data sources and applies two buffer-based methods. The parameter used for determining the different sizes (which range from 5 km up to 100 km) has been the length of the polygons’ perimeter, and for each sample size 1000 simulations were run. After completing the simulation process, the comparisons between the estimated distribution functions for each sample and population distribution function were carried out by means of the Kolmogorov–Smirnov test. Results show a significant reduction in the variability of estimations when sample size increased from 5 km to 100 km. Numéro de notice : A2018-346 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.3390/ijgi7060200 Date de publication en ligne : 28/05/2018 En ligne : https://doi.org/10.3390/ijgi7060200 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=90570
in ISPRS International journal of geo-information > vol 7 n° 6 (June 2018)[article]Modeling aggregated expertise of user contributions to assess the credibility of OpenStreetMap features / Bani Idham Muttaqien in Transactions in GIS, vol 22 n° 3 (June 2018)
[article]
Titre : Modeling aggregated expertise of user contributions to assess the credibility of OpenStreetMap features Type de document : Article/Communication Auteurs : Bani Idham Muttaqien, Auteur ; Franck O. Ostermann, Auteur ; Robert Lemmens, Auteur Année de publication : 2018 Article en page(s) : pp 823 - 841 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] contenu généré par les utilisateurs
[Termes IGN] données localisées des bénévoles
[Termes IGN] expertise
[Termes IGN] fiabilité des données
[Termes IGN] OpenStreetMap
[Termes IGN] qualité des données
[Termes IGN] utilisateur civilRésumé : (Auteur) The emergence of volunteered geographic information (VGI) during the past decade has fueled a wide range of research and applications. The assessment of VGI quality and fitness‐of‐use is still a challenge because of the non‐standardized and crowdsourced data collection process, as well as the unknown skill and motivation of the contributors. However, the frequent approach of assessing VGI quality against external data sources using ISO quality standard measures is problematic because of a frequent lack of available external (reference) data, and because for certain types of features, VGI might be more up‐to‐date than the reference data. Therefore, a VGI‐intrinsic measure of quality is highly desirable. This study proposes such an intrinsic measure of quality by developing the concept of aggregated expertise based on the characteristics of a feature's contributors. The article further operationalizes this concept and examines its feasibility through a case study using OpenStreetMap (OSM). The comparison of model OSM feature quality with information from a field survey demonstrates the successful implementation of this novel approach. Numéro de notice : A2018-580 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/tgis.12454 Date de publication en ligne : 17/08/2018 En ligne : https://doi.org/10.1111/tgis.12454 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92328
in Transactions in GIS > vol 22 n° 3 (June 2018) . - pp 823 - 841[article]Volunteered geographic information quality assessment using trust and reputation modelling in land administration systems in developing countries / Kealeboga K. Moreri in International journal of geographical information science IJGIS, vol 32 n° 5-6 (May - June 2018)
[article]
Titre : Volunteered geographic information quality assessment using trust and reputation modelling in land administration systems in developing countries Type de document : Article/Communication Auteurs : Kealeboga K. Moreri, Auteur ; David Fairbairn, Auteur ; Philip James, Auteur Année de publication : 2018 Article en page(s) : pp 931 - 959 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Cadastre étranger
[Termes IGN] base de données foncières
[Termes IGN] données localisées des bénévoles
[Termes IGN] pays en développement
[Termes IGN] qualité des donnéesRésumé : (Auteur) This article presents an innovative approach to establish the quality and credibility of Volunteered Geographic Information (VGI) such that it can be considered in Land Administration Systems (LAS) on a Fit for Purpose (FFP) basis. A participatory land information system can provide affordable and timely FFP information about land and its resources. However, the establishment of such a system involves more than just technical solutions and administrative procedures: many social, economic and political aspects must be considered. Innovative approaches like VGI can help address the lack of accurate, reliable and FFP land information for LAS, but integration of such sources relies on the quality and credibility of VGI. Verifying volunteer efforts can be difficult without reference to ground truth: a novel Trust and Reputation Modelling methodology is proposed as a suitable technique to effect such VGI data set validation. This method has been applied to successfully demonstrate that VGI can produce accurate and reliable data sets which can be used to conduct regular systematic updates of geographic information in official systems. It relies on a view that the public can police themselves in establishing proxy measures of VGI quality thus facilitating VGI to be used on a FFP basis in LAS. Numéro de notice : A2018-195 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/13658816.2017.1409353 Date de publication en ligne : 25/01/2018 En ligne : https://doi.org/10.1080/13658816.2017.1409353 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=89860
in International journal of geographical information science IJGIS > vol 32 n° 5-6 (May - June 2018) . - pp 931 - 959[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-2018031 RAB Revue Centre de documentation En réserve L003 Disponible An efficient visualization method for polygonal data with dynamic simplification / Mingguang Wu in ISPRS International journal of geo-information, vol 7 n° 4 (April 2018)
[article]
Titre : An efficient visualization method for polygonal data with dynamic simplification Type de document : Article/Communication Auteurs : Mingguang Wu, Auteur ; Taisheng Chen, Auteur ; Kun Zhang, Auteur ; Zhimin Jing, Auteur ; et al., Auteur Année de publication : 2018 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] algorithme de Douglas-Peucker
[Termes IGN] données localisées
[Termes IGN] intégrité topologique
[Termes IGN] maillage
[Termes IGN] OpenStreetMap
[Termes IGN] polygone
[Termes IGN] polyligne
[Termes IGN] simplification de contour
[Termes IGN] tessellation
[Termes IGN] visualisation de données
[Vedettes matières IGN] GénéralisationRésumé : (Auteur) Polygonal data often require rendering with symbolization and simplification in geovisualization. A common issue in existing methods is that simplification, symbolization and rendering are addressed separately, causing computational and data redundancies that reduce efficiency, especially when handling large complex polygonal data. Here, we present an efficient polygonal data visualization method by organizing the simplification, tessellation and rendering operations into a single mesh generalization process. First, based on the sweep line method, we propose a topology embedded trapezoidal mesh data structure to organize the tessellated polygons. Second, we introduce horizontal and vertical generalization operations to simplify the trapezoidal meshes. Finally, we define a heuristic testing algorithm to efficiently preserve the topological consistency. The method is tested using three OpenStreetMap datasets and compared with the Douglas Peucker algorithm and the Binary Line Generalization tree-based method. The results show that the proposed method improves the rendering efficiency by a factor of six. Efficiency-sensitive mapping applications such as emergency mapping could benefit from this method, which would significantly improve their visualization performances. Numéro de notice : A2018-108 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.3390/ijgi7040138 En ligne : https://doi.org/10.3390/ijgi7040138 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=89537
in ISPRS International journal of geo-information > vol 7 n° 4 (April 2018)[article]Inference and analysis across spatial supports in the big data era : Uncertain point observations and geographic contexts / Colin Robertson in Transactions in GIS, vol 22 n° 2 (April 2018)PermalinkA taxonomy of quality assessment methods for volunteered and crowdsourced geographic information / Lívia Castro Degrossi in Transactions in GIS, vol 22 n° 2 (April 2018)Permalink3D micro-mapping : Towards assessing the quality of crowdsourcing to support 3D point cloud analysis / Benjamin Herfort in ISPRS Journal of photogrammetry and remote sensing, vol 137 (March 2018)PermalinkAnalyse du risque végétation dans les emprises ferroviaires à partir de données LiDAR acquises par drones / Luc Perrin in XYZ, n° 154 (mars - mai 2018)PermalinkInformer sur la qualité pour favoriser l’ouverture des données : proposition d’une méthode basée sur la norme ISO 19157 / Stéphane Lévêque in Signature, n° 65 (mars 2018)PermalinkProgrès de la cartographie forestière mais persistance d'incertitudes : Cas de Madagascar / Georges Serpantié in Cartes & Géomatique, n° 235-236 (mars - juin 2018)PermalinkQuality assessment and accessibility mapping in an image-based geocrowdsourcing testbed / Matthew T. Rice in Cartographica, vol 53 n° 1 (Spring 2018)PermalinkQuelle cohérence nationale des données géographiques des schémas régionaux de cohérence écologiques / Dominique Andrieu in Cartes & Géomatique, n° 235-236 (mars - juin 2018)PermalinkThe effect of acquisition error and level of detail on the accuracy of spatial analyses / Filip Biljecki in Cartography and Geographic Information Science, Vol 45 n° 2 (March 2018)PermalinkA grounding-based ontology of data quality measures / Franz-Benjamin Mocnik in Journal of Spatial Information Science (JoSIS), n° 16 ([01/02/2018])Permalink