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A polyhedra-based model for moving regions in databases / Florian Heinz in International journal of geographical information science IJGIS, vol 34 n° 1 (January 2020)
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Titre : A polyhedra-based model for moving regions in databases Type de document : Article/Communication Auteurs : Florian Heinz, Auteur ; Ralf Hartmut Güting, Auteur Année de publication : 2020 Article en page(s) : pp 41 - 73 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes d'information géographique
[Termes descripteurs IGN] base de données orientée objet
[Termes descripteurs IGN] CGAL
[Termes descripteurs IGN] implémentation (informatique)
[Termes descripteurs IGN] isomorphisme
[Termes descripteurs IGN] MADS
[Termes descripteurs IGN] modélisation spatio-temporelle
[Termes descripteurs IGN] objet mobile
[Termes descripteurs IGN] polyèdreRésumé : (auteur) Moving objects databases store and process objects with a focus on their spatiotemporal behaviour. To achieve this, the model of the data must be suitable to efficiently store and process moving objects. Currently, a unit-based model is widely used, where each moving object is divided into one or more time intervals, during which the object behaves uniformly. This model is also used for a data type called moving regions, which resembles moving and shape changing regions as, for example, forest fires or cloud fields. However, this model struggles to support operations like union, difference or intersection of two moving regions; the resulting objects are unnecessarily bloated and uncomfortable to handle because the resulting number of units is generally very high. In this paper, an alternative model for moving regions is proposed, which is based on polyhedra. Furthermore, this work develops an isomorphism between moving regions and polyhedra including all relevant operations, which has the additional advantage that several implementations for those are already readily available; this is demonstrated by a reference implementation using the existing and well-tested Computational Geometry Algorithms Library (CGAL). Numéro de notice : A2020-007 Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/13658816.2019.1616090 date de publication en ligne : 17/05/2019 En ligne : https://doi.org/10.1080/13658816.2019.1616090 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94387
in International journal of geographical information science IJGIS > vol 34 n° 1 (January 2020) . - pp 41 - 73[article]An indoor navigation model and its network extraction / Filippo Mortari in Applied geomatics, Vol 11 n° 4 (December 2019)
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Titre : An indoor navigation model and its network extraction Type de document : Article/Communication Auteurs : Filippo Mortari, Auteur ; Eliseo Clementini, Auteur ; Sisi Zlatanova, Auteur ; Liu Liu, Auteur Année de publication : 2019 Article en page(s) : pp 413–427 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géomatique
[Termes descripteurs IGN] axe médian
[Termes descripteurs IGN] CityGML
[Termes descripteurs IGN] diagramme de Voronoï
[Termes descripteurs IGN] espace topologique
[Termes descripteurs IGN] extraction automatique
[Termes descripteurs IGN] extraction de données
[Termes descripteurs IGN] modèle géométrique du bâti
[Termes descripteurs IGN] modèle numérique du bâti
[Termes descripteurs IGN] modélisation 3D
[Termes descripteurs IGN] positionnement en intérieur
[Termes descripteurs IGN] raisonnement spatiotemporel
[Termes descripteurs IGN] représentation spatio-sémantiqueRésumé : (auteur) We propose a navigation model for indoor environments that combines a 3D geometric modeling of buildings with connection properties of spaces and semantic elements such as openings and installations. The model is an extension of the IndoorGML standard navigation module with a twofold benefit: the extension facilitated the data import from the international standard CityGML and introduced the semantics of various fixtures in indoor space of buildings making the navigation model more suitable for human needs. Several experiments have been conducted by extracting networks from CityGML data and performing a comparison with other network construction techniques. The second contribution of the paper is an algorithm for the automatic extraction of the navigation network. Such an algorithm is a hybrid solution between medial axis approaches and visibility graph approaches. Normally, medial axes approaches are a good representation of human navigation in narrow corridors, especially to avoid obstacles, but introduce distortions in open space. On the other hand, visibility approaches work better in open spaces. In our extraction technique, the resulting network takes advantages of both approaches and better mimics human beings’ navigation in indoor environments. Numéro de notice : A2019-534 Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s12518-019-00273-8 date de publication en ligne : 17/06/2019 En ligne : https://doi.org/10.1007/s12518-019-00273-8 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94129
in Applied geomatics > Vol 11 n° 4 (December 2019) . - pp 413–427[article]Analysing the positional accuracy of GNSS multi-tracks obtained from VGI sources to generate improved 3D mean axes / Antonio Tomás Mozas-Calvache in International journal of geographical information science IJGIS, vol 33 n°11 (November 2019)
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Titre : Analysing the positional accuracy of GNSS multi-tracks obtained from VGI sources to generate improved 3D mean axes Type de document : Article/Communication Auteurs : Antonio Tomás Mozas-Calvache, Auteur ; Francisco Javier Ariza-López, Auteur Année de publication : 2019 Article en page(s) : pp 2170 - 2187 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Infrastructure de données
[Termes descripteurs IGN] axe médian
[Termes descripteurs IGN] contenu généré par les utilisateurs
[Termes descripteurs IGN] données localisées 3D
[Termes descripteurs IGN] données localisées des bénévoles
[Termes descripteurs IGN] positionnement par GNSS
[Termes descripteurs IGN] précision du positionnement
[Termes descripteurs IGN] qualité des données
[Termes descripteurs IGN] réseau routier
[Termes descripteurs IGN] trace GPS
[Termes descripteurs IGN] vitesse de déplacementRésumé : (auteur) The sharing of Global Navigation Satellite System (GNSS) tracks on the Internet is increasing enormously. Every day a great number of users capture routes using different devices and share these data. Individually these tracks present a poor positional accuracy because these devices obtain positions with accuracy of about 5-10 metres. In addition, they are usually captured for navigation and not for surveying. However, we can take advantage of the great quantity of tracks of the same linear element in order to obtain a more accurate solution. This study analyses this possibility using a wide set of tracks obtained in known conditions. We emulated those tracks obtained by Volunteered Geographic Information (VGI) users and we compared the mean axis obtained using all tracks with others obtained from a more accurate source. Additionally, we analyse the displacement of other axes obtained by varying several parameters such as the number of tracks and their length or by dividing the route into sections in function of sinuosity, etc. The results have shown an improved 3D mean axis and the viability of the method proposed in this study in order to use axes obtained from several tracks in maps at certain scales. Numéro de notice : A2019-429 Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/13658816.2019.1645335 date de publication en ligne : 26/07/2019 En ligne : https://doi.org/10.1080/13658816.2019.1645335 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93563
in International journal of geographical information science IJGIS > vol 33 n°11 (November 2019) . - pp 2170 - 2187[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-2019082 RAB Revue Centre de documentation En réserve 3L Disponible 079-2019081 SL Revue Centre de documentation Revues en salle Disponible A method for drawing vertical curve in longitudinal profile in road project / Hüseyin İnce in Survey review, vol 51 n° 368 (September 2019)
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Titre : A method for drawing vertical curve in longitudinal profile in road project Type de document : Article/Communication Auteurs : Hüseyin İnce, Auteur ; Nuri Erdem, Auteur Année de publication : 2019 Article en page(s) : pp 413 - 421 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse numérique
[Termes descripteurs IGN] courbe
[Termes descripteurs IGN] échelle cartographique
[Termes descripteurs IGN] gradient de pente
[Termes descripteurs IGN] profil en long
[Termes descripteurs IGN] projet routierRésumé : (Auteur) In road projects, there is a difficulty in drawing tangent points of the calculated vertical curve, turning point and intermediate points due to horizontal and vertical scale differences. This problem is brought about by the fact that proportional relationship between the two different scales is not known for a length with a certain slope in longitudinal profile. This study proposes a method to eliminate this problem. It also gives an example and discusses the findings. Numéro de notice : A2019-367 Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/00396265.2018.1470071 date de publication en ligne : 15/05/2018 En ligne : https://doi.org/10.1080/00396265.2018.1470071 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93473
in Survey review > vol 51 n° 368 (September 2019) . - pp 413 - 421[article]Empirical stochastic model of detected target centroids: Influence on registration and calibration of terrestrial laser scanners / Tomislav Medic in Journal of applied geodesy, vol 13 n° 3 (July 2019)
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Titre : Empirical stochastic model of detected target centroids: Influence on registration and calibration of terrestrial laser scanners Type de document : Article/Communication Auteurs : Tomislav Medic, Auteur ; Christoph Holst, Auteur ; Jannik Janssen, Auteur ; Heiner Kuhlmann, Auteur Année de publication : 2019 Article en page(s) : pp 179 – 197 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes descripteurs IGN] centroïde
[Termes descripteurs IGN] compensation par moindres carrés
[Termes descripteurs IGN] détection de cible
[Termes descripteurs IGN] données lidar
[Termes descripteurs IGN] données localisées 3D
[Termes descripteurs IGN] étalonnage d'instrument
[Termes descripteurs IGN] incertitude de mesurage
[Termes descripteurs IGN] métrologie dimensionelle
[Termes descripteurs IGN] modèle stochastique
[Termes descripteurs IGN] télémètre laser terrestreRésumé : (auteur) The target-based point cloud registration and calibration of terrestrial laser scanners (TLSs) are mathematically modeled and solved by the least-squares adjustment. However, usual stochastic models are simplified to a large amount: They generally employ a single point measurement uncertainty based on the manufacturers’ specifications. This definition does not hold true for the target-based calibration and registration due to the fact that the target centroid is derived from multiple measurements and its uncertainty depends on the detection procedure as well. In this study, we empirically investigate the precision of the target centroid detection and define an empirical stochastic model in the form of look-up tables. Furthermore, we compare the usual stochastic model with the empirical stochastic model on several point cloud registration and TLS calibration experiments. There, we prove that the values of usual stochastic models are underestimated and incorrect, which can lead to multiple adverse effects such as biased results of the estimation procedures, a false a posteriori variance component analysis, false statistical testing, and false network design conclusions. In the end, we prove that some of the adverse effects can be mitigated by employing the a priori knowledge about the target centroid uncertainty behavior. Numéro de notice : A2019-284 Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1515/jag-2018-0032 date de publication en ligne : 22/03/2019 En ligne : https://doi.org/10.1515/jag-2018-0032 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93119
in Journal of applied geodesy > vol 13 n° 3 (July 2019) . - pp 179 – 197[article]Building detection and regularisation using DSM and imagery information / Yousif A. Mousa in Photogrammetric record, vol 34 n° 165 (March 2019)
PermalinkCentral place indexing : hierarchical linear indexing systems for mixed-aperture hexagonal discrete global grid systems / Kevin Sahr in Cartographica, vol 54 n° 1 (spring 2019)
PermalinkGeographic space as a living structure for predicting human activities using big data / Bin Jiang in International journal of geographical information science IJGIS, Vol 33 n° 3-4 (March - April 2019)
PermalinkThinking outside the square: Evidence that plot shape and layout in forest inventories can bias estimates of stand metrics / Thomas S. H. Paul in Methods in ecology and evolution, vol 10 n° 3 (March 2019)
PermalinkPermalinkSimultaneous chain-forming and generalization of road networks / Susanne Wenzel in Photogrammetric Engineering & Remote Sensing, PERS, vol 85 n° 1 (January 2019)
PermalinkDEM refinement by low vegetation removal based on the combination of full waveform data and progressive TIN densification / Hongchao Ma in ISPRS Journal of photogrammetry and remote sensing, vol 146 (December 2018)
PermalinkHistoric reconstruction of reservoir topography using contour line interpolation and structure from motion photogrammetry / Ana Casado in International journal of geographical information science IJGIS, vol 32 n° 11-12 (November - December 2018)
PermalinkA topology-preserving polygon rasterization algorithm / Chen Zhou in Cartography and Geographic Information Science, Vol 45 n° 6 (November 2018)
PermalinkBoresight calibration of low point density Lidar sensors / Sudhagar Nagarajan in Photogrammetric Engineering & Remote Sensing, PERS, vol 84 n° 10 (October 2018)
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