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Titre : Learning to map street-side objects using multiple views Type de document : Thèse/HDR Auteurs : Ahmed Samy Nassar, Auteur ; Sébastien Lefèvre, Directeur de thèse ; Jan Dirk Wegner, Directeur de thèse Editeur : Vannes : Université de Bretagne Sud Année de publication : 2021 Importance : 139 p. Format : 21 x 30 cm Note générale : bibliographie
Thèse de Doctorat de l'Université de Bretagne Sud, spécialité InformatiqueLangues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] apprentissage profond
[Termes IGN] arbre urbain
[Termes IGN] cartographie par internet
[Termes IGN] classification par réseau neuronal convolutif
[Termes IGN] détection d'objet
[Termes IGN] données multisources
[Termes IGN] estimation de pose
[Termes IGN] géolocalisation
[Termes IGN] graphe
[Termes IGN] image Streetview
[Termes IGN] inventaire
[Termes IGN] mobilier urbain
[Termes IGN] vision par ordinateurIndex. décimale : THESE Thèses et HDR Résumé : (auteur) Creating inventories of street-side objects and their monitoring in cities is a labor-intensive and costly process. Field workers are known to conduct this process on-site to record properties about the object. These properties can be the location, species, height, and health of a tree as an example. To monitor cities, gathering such information on a large scale becomes challenging. With the abundance of imagery, adequate coverage of a city is achieved from different views provided by online mapping services (e.g., Google Maps and Street View, Mapillary). The availability of such imagery allows efficient creation and updating of inventories of street-side objects status by using computer vision methods such as object detection and multiple object tracking. This thesis aims at detecting and geo-localizing street-side objects, especially trees and street signs, from multiple views using novel deep learning methods. Note de contenu : 1- Introduction
2- Background
3- Multi-view instance matching with learned geometric soft-constraints
4- Simultaneous multi-view instance detection with learned geometric softconstraints
5- GeoGraphV2: Graph-based aerial & street view multi-view object detection with geometric cues end-to-end
6- ConclusionNuméro de notice : 28674 Affiliation des auteurs : non IGN Thématique : IMAGERIE/INFORMATIQUE Nature : Thèse française Note de thèse : Thèse de Doctorat : Informatique : Université de Bretagne Sud : 2021 Organisme de stage : IRISA DOI : sans En ligne : https://hal.science/tel-03523658 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99920
Titre : Map matching for semi-restricted trajectories Type de document : Article/Communication Auteurs : Timon Behr, Auteur ; Thomas van Dijk, Auteur ; Axel Forsch, Auteur ; Jan‐Henrik Haunert, Auteur ; Sabine Storandt, Auteur Editeur : Leibniz [Allemagne] : Schloss Dagstuhl – Leibniz-Zentrum für Informatik Année de publication : 2021 Conférence : GIScience 2021, 11th International Conference on Geographic Information Science 27/09/2021 30/09/2021 Poznań Pologne Open Access Proceedings Importance : 16 p. Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géomatique
[Termes IGN] appariement de cartes
[Termes IGN] cycliste
[Termes IGN] information sémantique
[Termes IGN] OpenStreetMap
[Termes IGN] piéton
[Termes IGN] positionnement par GPS
[Termes IGN] réseau routier
[Termes IGN] trajet (mobilité)Résumé : (auteur) We consider the problem of matching trajectories to a road map, giving particular consideration to trajectories that do not exclusively follow the underlying network. Such trajectories arise, for example, when a person walks through the inner part of a city, crossing market squares or parking lots. We call such trajectories semi-restricted. Sensible map matching of semi-restricted trajectories requires the ability to differentiate between restricted and unrestricted movement. We develop in this paper an approach that efficiently and reliably computes concise representations of such trajectories that maintain their semantic characteristics. Our approach utilizes OpenStreetMap data to not only extract the network but also areas that allow for free movement (as e.g. parks) as well as obstacles (as e.g. buildings). We discuss in detail how to incorporate this information in the map matching process, and demonstrate the applicability of our method in an experimental evaluation on real pedestrian and bicycle trajectories. Numéro de notice : C2021-081 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Communication DOI : 10.4230/LIPIcs.GIScience.2021.II.12 Date de publication en ligne : 14/09/2021 En ligne : https://doi.org/10.4230/LIPIcs.GIScience.2021.II.12 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=100939 Positional uncertainty of network RTK observations in a modern datum / T. Bernstein in Journal of geodetic science, vol 11 n° 1 (January 2021)
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Titre : Positional uncertainty of network RTK observations in a modern datum Type de document : Article/Communication Auteurs : T. Bernstein, Auteur ; Volker Janssen, Auteur Année de publication : 2021 Article en page(s) : pp 38 - 47 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] compensation de coordonnées
[Termes IGN] Geocentric Datum of Australia 2020
[Termes IGN] incertitude de position
[Termes IGN] Nouvelle-Galles du Sud
[Termes IGN] positionnement cinématique en temps réel
[Termes IGN] station virtuelle de référenceRésumé : (auteur) The Geocentric Datum of Australia 2020 (GDA2020) is Australia’s new and much improved national datum. It is based on a single, nationwide leastsquares network adjustment that rigorously propagates uncertainty. This paper explores three options to include Network Real-Time Kinematic (NRTK) observations and their Positional Uncertainty (PU) in the survey control network of New South Wales (NSW) via the GDA2020 state adjustment. In the first option, PU is empirically estimated based on a dataset of more than 1,500 observations to obtain values that can be uniformly applied to all NRTK observations. In the second option, PU is calculated for each NRTK observation, based on the coordinate quality indicators provided by the Global Navigation Satellite System (GNSS) equipment. Both options continue to treatNRTK observations as point-based position solutions, resulting in poor correlation with surrounding surveycontrol marks. The third option overcomes this issue by utilising the automatically computed GNSS baselines between NRTK observations and their Virtual Reference Station (VRS) to create a connected network that can be adjusted like a static GNSS network. Using a typical urban NRTK survey in Sydney as an example, it is shown that this method offers a rigorous computation of PU, while maintaining the quick and easy nature of NRTK positioning. Numéro de notice : A2021-980 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1515/jogs-2020-0116 Date de publication en ligne : 10/08/2021 En ligne : https://doi.org/10.1515/jogs-2020-0116 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=100977
in Journal of geodetic science > vol 11 n° 1 (January 2021) . - pp 38 - 47[article]Probabilistic positioning in mobile phone network and its consequences for the privacy of mobility data / Aleksey Ogulenko in Computers, Environment and Urban Systems, vol 85 (January 2021)
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Titre : Probabilistic positioning in mobile phone network and its consequences for the privacy of mobility data Type de document : Article/Communication Auteurs : Aleksey Ogulenko, Auteur ; Itzhak Benenson, Auteur ; Itzhak Omer, Auteur Année de publication : 2021 Article en page(s) : n° 101550 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] antenne
[Termes IGN] classification bayesienne
[Termes IGN] confidentialité
[Termes IGN] diagramme de Voronoï
[Termes IGN] estimation bayesienne
[Termes IGN] géolocalisation
[Termes IGN] inférence
[Termes IGN] protection de la vie privée
[Termes IGN] réseau téléphonique
[Termes IGN] téléphonie mobile
[Termes IGN] tessellationRésumé : (auteur) The traditional approach to mobile phone positioning is based on the assumption that the geographical location of a cell tower recorded in a Call Details Record (CDR) is a proxy for a device's location. A Voronoi tessellation is then constructed based on the entire network of cell towers and this tessellation is considered as a coordinate system, with the device located in a Voronoi polygon of a cell tower that is recorded in the CDR. If Voronoi-based positioning is correct, the uniqueness of the device trajectory is very high, and the device can be identified based on 3–5 of its recorded locations. We investigate a probabilistic approach to device positioning that is based on knowledge of each antennas' parameters and number of connections, as dependent on the distance to the antenna. The critical difference between the Voronoi-based and the real world layout is in the essential overlap of the antennas' service areas: The device that is located in a cell tower's polygon can be served by a more distant antenna that is chosen by the network system to balance the network load. Combining data on the distance distribution of the number of connections available for each antenna in the network, we resolve the overlap problem by applying Bayesian inference and construct a realistic distribution of the device location. Probabilistic device positioning demands a full revision of mobile phone privacy and new full set of tools for data analysis. Numéro de notice : A2021-005 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/MATHEMATIQUE Nature : Article DOI : 10.1016/j.compenvurbsys.2020.101550 Date de publication en ligne : 14/10/2020 En ligne : https://doi.org/10.1016/j.compenvurbsys.2020.101550 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96272
in Computers, Environment and Urban Systems > vol 85 (January 2021) . - n° 101550[article]SBAS-aided GPS positioning with an extended ionosphere map at the boundaries of WAAS service area / Mingyu Kim in Remote sensing, vol 13 n° 1 (January-1 2021)
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Titre : SBAS-aided GPS positioning with an extended ionosphere map at the boundaries of WAAS service area Type de document : Article/Communication Auteurs : Mingyu Kim, Auteur ; Jeongrae Kim, Auteur Année de publication : 2021 Article en page(s) : n° 151 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] correction
[Termes IGN] correction ionosphérique
[Termes IGN] décalage d'horloge
[Termes IGN] GPS assisté pour la navigation (technologies)
[Termes IGN] orbite
[Termes IGN] positionnement par GNSS
[Termes IGN] retard ionosphèrique
[Termes IGN] Wide Area Augmentation SystemRésumé : (auteur) Space-based augmentation system (SBAS) provides correction information for improving the global navigation satellite system (GNSS) positioning accuracy in real-time, which includes satellite orbit/clock and ionospheric delay corrections. At SBAS service area boundaries, the correction is not fully available to GNSS users and only a partial correction is available, mostly satellite orbit/clock information. By using the geospatial correlation property of the ionosphere delay information, the ionosphere correction coverage can be extended by a spatial extrapolation algorithm. This paper proposes extending SBAS ionosphere correction coverage by using a biharmonic spline extrapolation algorithm. The wide area augmentation system (WAAS) ionosphere map is extended and its ionospheric delay error is compared with the GPS Klobuchar model. The mean ionosphere error reduction at low latitude is 52.3%. The positioning accuracy of the extended ionosphere correction method is compared with the accuracy of the conventional SBAS positioning method when only a partial set of SBAS corrections are available. The mean positioning error reduction is 44.8%, and the positioning accuracy improvement is significant at low latitude. Numéro de notice : A2021-075 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.3390/rs13010151 Date de publication en ligne : 05/01/2021 En ligne : https://doi.org/10.3390/rs13010151 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96813
in Remote sensing > vol 13 n° 1 (January-1 2021) . - n° 151[article]Sea level acceleration under the magnifier / Huseyin Baki Iz in Journal of geodetic science, vol 11 n° 1 (January 2021)
PermalinkSeasonal flow variability of Greenlandic glaciers : satellite observations and numerical modeling to study driving processes / Anna Derkacheva (2021)
PermalinkSherloc: a knowledge-driven algorithm for geolocating microblog messages at sub-city level / Laura Di Rocco in International journal of geographical information science IJGIS, vol 35 n° 1 (January 2021)
PermalinkStatistical analysis of vertical land motions and sea level measurements at the coast / Kevin Gobron (2021)
PermalinkPermalinkTemporal calibration and synchronization of robotic total stations for kinematic multi-sensor-systems / Tomas Thalmann in Journal of applied geodesy, vol 15 n° 1 (January 2021)
PermalinkVers un protocole de calibration de caméras statiques à l'aide d'un drone / Jean-François Villeforceix (2021)
PermalinkCORS usage for GPS survey in the greater accra region: Advantages, limitation, and suggested remedies / Sebastian Botsyo in Journal of Geovisualization and Spatial Analysis, vol 4 n° 2 (December 2020)
PermalinkExploring the heterogeneity of human urban movements using geo-tagged tweets / Ding Ma in International journal of geographical information science IJGIS, vol 34 n° 12 (December 2020)
PermalinkIntercomparisons of precipitable water vapour derived from radiosonde, GPS and sunphotometer observations / Shaoqi Gong in Geodetski vestnik, vol 64 n° 4 (December 2020 - February 2021)
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