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Scalable and privacy-respectful interactive discovery of place semantics from human mobility traces / Natalia Andrienko in Information visualization, vol 15 n° 2 (April 2016)
[article]
Titre : Scalable and privacy-respectful interactive discovery of place semantics from human mobility traces Type de document : Article/Communication Auteurs : Natalia Andrienko, Auteur ; Gennady Andrienko, Auteur ; Georg Fuchs, Auteur ; Piotr Jankowski, Auteur Année de publication : 2016 Article en page(s) : pp 117 - 153 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] analyse géovisuelle
[Termes IGN] analyse multicritère
[Termes IGN] données spatiotemporelles
[Termes IGN] information sémantique
[Termes IGN] migration pendulaire
[Termes IGN] mobilité urbaine
[Termes IGN] protection de la vie privée
[Termes IGN] réseau social
[Termes IGN] téléphone intelligent
[Termes IGN] trace GPS
[Vedettes matières IGN] GéovisualisationRésumé : (auteur) Mobility diaries of a large number of people are needed for assessing transportation infrastructure and spatial development planning. Acquisition of personal mobility diaries through population surveys is a costly and error-prone endeavour. We examine an alternative approach to obtaining similar information from episodic digital traces of people’s presence in various locations, which appear when people use their mobile devices for making phone calls, accessing the Internet or posting georeferenced contents (texts, photos or videos) in social media. Having episodic traces of a person over a long time period, it is possible to detect significant (repeatedly visited) personal places and identify them as home, work or place of social activities based on temporal patterns of a person’s presence in these places. Such analysis, however, can lead to compromising personal privacy. We have investigated the feasibility of deriving place meanings and reconstructing personal mobility diaries while preserving the privacy of individuals whose data are analysed. We have devised a visual analytics approach and a set of supporting tools making such privacy-preserving analysis possible. The approach was tested in two case studies with publicly available data: simulated tracks from the VAST Challenge 2014 and real traces built from georeferenced Twitter posts. Numéro de notice : A2016--019 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1177/1473871615581216 En ligne : https://doi.org/10.1177/1473871615581216 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83874
in Information visualization > vol 15 n° 2 (April 2016) . - pp 117 - 153[article]
Titre : Crowd-sourced reconstruction of building interiors Type de document : Thèse/HDR Auteurs : Michael Peter, Auteur ; Dieter Fritsch, Directeur de thèse Editeur : Munich : Bayerische Akademie der Wissenschaften Année de publication : 2016 Collection : DGK - C, ISSN 0065-5325 num. 768 Importance : 147 p. ISBN/ISSN/EAN : 978-3-7696-5180-5 Note générale : bibliographie Langues : Anglais (eng) Allemand (ger) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] carte d'intérieur
[Termes IGN] cartographie collaborative
[Termes IGN] données localisées des bénévoles
[Termes IGN] échelle cartographique
[Termes IGN] image binaire
[Termes IGN] modélisation 2D
[Termes IGN] modélisation 3D du bâti BIM
[Termes IGN] navigation à l'estime
[Termes IGN] numérisation de carte
[Termes IGN] plan incendie
[Termes IGN] positionnement en intérieur
[Termes IGN] segmentation binaire
[Termes IGN] squelettisation
[Termes IGN] trace GPSRésumé : (auteur) Location-based services (LBS) have gained huge commercial and scientific interest in recent years, due to the ubiquitous and free availability of maps, global positioning systems, and smartphones. To date, maps and positioning solutions are mostly only available for outdoor use. However, humans spend most of their time indoors, rendering indoor LBS interesting for applications such as location-based advertisement, customer tracking and customer flow analysis. Neither of the two prerequisites for indoor LBS - a map of the user's environment and a positioning system - is currently generally available: Most positioning methods currently under scientific investigation are based either on fingerprint maps of electro-magnetic signals (e.g. WiFi) or inertial measurement units. To overcome the flaws of these methods, they are often supported by models for the human movement which in turn rely on indoor maps. Ready-made maps, on the other hand, are generally unavailable due to indoor mapping being mostly manual, expensive and tedious. The vast amount of unmapped indoor space therefore calls for the transfer of methods used by Volunteered Geographic Information (VGI) communities like OpenStreetMap to indoor mapping. These methods comprise the digitization of features of interest such as building outlines from aerial images released to the community and the use of position traces. In this thesis, approaches are illustrated which can serve to enable this transfer. On the one hand, the thesis shows how photographs of evacuation plans - which are a compulsory part of the safety equipment of publicly used buildings in many countries - can substitute for the aerial images in the indoor domain. Due to the standardised nature of such plans, the manual digitization employed by VGI mappers in the outdoor domain can be replaced by an automatic reverse-engineering pipeline. To this end, the image is pre-processed and symbols, which depict evacuation routes or emergency equipment, are detected. Subsequently, foreground objects (i.e. walls) are distinguished from the background using an adequate binarisation operation. Based on the binary image, the sought-after vector information can be extracted by skeletonisation and skeleton tracing. The model is finalised by a bridging operation of the previously detected symbols which occlude parts of walls or stairs. As the model resulting from these operations is only available in a coordinate system defined by the original image, the transformation to a world-coordinate system or, at least, the unknown scale has to be determined. To this end, the indoor model is matched to an available model of the building's external shell. By detection of stairs, an approximate floor height can be computed and the 2D model is extruded to a 3D model. On the other hand, geometric features and semantic annotations may be added to existing models using pedestrian traces recorded by an indoor positioning system. As suitable generally available and low-cost systems do not exist yet, their existence is simulated in this work by a dead-reckoning system basing on a foot-mounted inertial measurement system. Methods for the derivation of the initial position and orientation necessary for the application of such a system are shown, as well as methods enabling the correction of remaining errors. The latter comprise an alignment approach using the external building shell and a map-matching method which employs the existing coarse model derived from the evacuation plan. Building on the collected pedestrian traces, semi-automatic and automatic approaches for the existing models' semantic and geometric refinement are presented which range from semantic annotation using the analysis of photographed doorplates to automatic door reconstruction. Furthermore, a geometric update of single rooms by conjoint analysis of the coarse model, pedestrian traces and a hand-held low-cost range camera is described. Lastly, works of indoor mapping are presented which are based on pedestrian traces and higher-level knowledge about the interior structure of the building modelled in an indoor grammar. Due to the differing characteristics of the two central elements of building interiors, corridors and rooms, the grammar is composed of a Lindenmayer system modelling the floor's corridor system and a split grammar describing the room layout which is found in the non-corridor spaces. The grammar is put to the test by applying it to distributedly collected noisy trace data. Numéro de notice : 19790 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Thèse étrangère Note de thèse : PhD Dissertation : Photogrammetry : Stuttgart : 2016 nature-HAL : Thèse DOI : 10.18419/opus-8729 En ligne : http://doi.org/10.18419/opus-8729 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=85009 Detection of potential updates of authoritative spatial databases by fusion of Volunteered Geographical Information from different sources / Stefan Ivanovic (2015)
Titre : Detection of potential updates of authoritative spatial databases by fusion of Volunteered Geographical Information from different sources Type de document : Article/Communication Auteurs : Stefan Ivanovic (1988 - 2020) , Auteur ; Ana-Maria Olteanu-Raimond , Auteur ; Sébastien Mustière , Auteur ; Thomas Devogele , Auteur Editeur : Milan : Politechnico di Milano Année de publication : 2015 Collection : Geomatics workbooks (Laboratorio di geomatica), ISSN 1591-092X num. 12 Conférence : FOSS4G 2015 Europe conference, Free and open-source software for geospatial 15/07/2015 17/07/2015 Como Italie open access abstracts Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] analyse comparative
[Termes IGN] appariement automatique
[Termes IGN] détection automatique
[Termes IGN] données localisées de référence
[Termes IGN] données localisées des bénévoles
[Termes IGN] Géoxygène (plateforme de généralisation)
[Termes IGN] mise à jour de base de données
[Termes IGN] PostgreSQL
[Termes IGN] précision de localisation
[Termes IGN] qualité des données
[Termes IGN] sport
[Termes IGN] trace GPSRésumé : (auteur) Nowadays, needs for very up to date referential spatial data increase significantly. Thus, a continuous update of authoritative spatial databases becomes highly demanding task in both aspects, technical and financial. In the same time, alternative sources of spatial data, such as Volunteered Geographical Information – VGI (Goodchild, 2007) seems to be suitable solution. This data is easy available and is being collected in almost every moment somewhere in the world. The main objective of our research is proposing a method for identifying potential updates in authoritative spatial databases using VGI data, more precisely GPS tracks. We identified walkway and tractor as very challenging types of roads for continuous update due to their intermittent nature (e.g. they appear and disappear very often) and various landscape (e.g. forest, high mountains, seashore, etc.). Even though, these types of roads are not of the highest priority for a national mapping agency, they are still very important for production of touristic maps and for other different applications such as defense, sport activities, etc. That is why we have focused on GPS traces obtained in sport activities. To detect potential update, links between similar features need to be defined. This step consists in applying a data matching algorithm in order to match VGI and authoritative data. Then, the question of VGI tracks quality arises. Furthermore, VGI traces are collected without any specified procedures, less or inexistent metadata, usually by low class GPS devices. Hence, heterogeneity of data is very high as well as spatial inaccuracy. In this work we focus on examination of data quality, especially on its spatial and temporal aspects. First, we present an overview of VGI data sources (websites) and the heterogeneities that characterize them. In terms of data, we can rely on spatiotemporal data (i.e. coordinates and sometimes elevation and timestamps) as well as on a variety of descriptive information in text format such as: type of activity, difficulty, trace description etc. Second, providing a comprehensive analysis of elements which affect GPS data quality is necessary. Sources of errors related to technical aspect of GPS data collection are partially important for our work. Since we use data obtained by low class GPS receivers, which positional accuracy is at meter level, we are not concerned about the sources that affect the accuracy at sub-meter level. Therefore, our attention is directed to identifying and classifying sources of errors according to which extent they affect positional accuracy of GPS tracks. Finally, we are interested in evaluation of data quality by analyzing VGI data itself, without comparing it to referential data. Thus, we tend to obtain the more statistical indicators of data quality that we can, such as indicators of: spatial dispersion, precision, reliability, correlation between data etc. As a result, a process of automatic collection of GPS traces from web-sites and storing them into PostgreSQL database was created. Evaluation of data quality is conducted by using an open source platform GeOxygene, developed by COGIT laboratory. Numéro de notice : C2015-040 Affiliation des auteurs : LASTIG COGIT+Ext (2012-2019) Thématique : GEOMATIQUE Nature : Communication nature-HAL : ComSansActesPubliés-Unpublished DOI : sans En ligne : http://geomatica.como.polimi.it/workbooks/n12/ Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83204 Documents numériques
en open access
Detection of potential updates - résuméAdobe Acrobat PDF
Titre : Using mobile phone traces to understand activity and mobility in Dakar, Senegal Type de document : Article/Communication Auteurs : Ed Manley, Auteur ; Adam Dennett, Auteur ; Michael Batty, Auteur Editeur : Leeds [Royaume-Uni] : University of Leeds Année de publication : 2015 Conférence : GISRUK 2015, 23th GIS Research UK annual conference 15/04/2015 17/04/2015 Leeds Royaume-Uni open access proceedings Importance : pp 387 - 395 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] analyse spatio-temporelle
[Termes IGN] Dakar (Sénégal)
[Termes IGN] distribution spatiale
[Termes IGN] données massives
[Termes IGN] mobilité urbaine
[Termes IGN] pays en développement
[Termes IGN] téléphone intelligent
[Termes IGN] trace GPS
[Vedettes matières IGN] GéovisualisationRésumé : (auteur) With the emergence of mobile phone trace datasets, new opportunities have arisen for improving the understanding large-scale mobility behaviours. The potential impact of these insight derived from these data is no more significant than in the developing country context, where existing data collection infrastructure is limited or non-existent. In this research, mobile phone data for Dakar, Senegal is used to better understand urban activity and mobility dynamics. To achieve this, a clustering method is introduced that extracts the spatial distribution, and the temporal characteristics, of the activities of individual mobile phone users. With this classification of individual locations of activity, citywide trends in activity and mobility over time are derived. The paper concludes in discussing the potential and limitations of this approach, and the outlook for associated analyses that employ mobile phone trace data. Numéro de notice : C2015-051 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/URBANISME Nature : Communication DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83865 Documents numériques
en open access
Using mobile phone tracesAdobe Acrobat PDF Analyse des préférences spatiales de la faune à partir de différentes sources de données géographiques / Laurence Jolivet (2014)
contenu dans Actes du Colloque International de Géomatique et d'Analyse Spatiale, SAGEO 2014 / Jérôme Gensel (2014)
Titre : Analyse des préférences spatiales de la faune à partir de différentes sources de données géographiques Type de document : Article/Communication Auteurs : Laurence Jolivet , Auteur ; Marianne Cohen, Auteur ; Anne Ruas , Auteur Editeur : [s.l.] : [s.n.] Année de publication : 2014 Conférence : SAGEO 2014, Spatial Analysis and GEOmatics 24/11/2014 27/11/2014 Saint-Martin-d'Hères, Grenoble France open access proceedings Langues : Français (fre) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] données localisées
[Termes IGN] faune
[Termes IGN] trace GPSRésumé : (auteur) La faune est influencée par les éléments du paysage lors de ses déplacements. Nous cherchons à déterminer si les préférences spatiales des animaux peuvent être détectées à partir de suivis GPS de renards, chevreuils et cerfs et en les intégrant dans un SIG conjointement aux données géographiques du Référentiel à Grande Échelle. Les analyses spatiales menées nous permettent de retrouver certaines préférences connues. Nous proposons ensuite des analyses complémentaires à partir d’autres sources de données, qui précisent ou nuancent le rôle des éléments du paysage. Numéro de notice : C2014-002 Affiliation des auteurs : LASTIG COGIT+Ext (2012-2019) Thématique : GEOMATIQUE Nature : Poster nature-HAL : Poster-avec-CL DOI : sans En ligne : https://halshs.hal.science/halshs-02344627 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=78469 Documents numériques
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Analyses des préférences spatiales de la faune - postprintAdobe Acrobat PDF Acquisition de connaissances sur les déplacements quotidiens des individus dans un contexte de risques naturels : Protocoles d’enquête à l’aide de technologies mobiles / Sidonie Christophe (2010)Permalink