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Exploring 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)
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[article]
Titre : Exploring the heterogeneity of human urban movements using geo-tagged tweets Type de document : Article/Communication Auteurs : Ding Ma, Auteur ; Toshihiro Osaragi, Auteur ; Takuya Oki, Auteur ; Bin Jiang, Auteur Année de publication : 2020 Article en page(s) : pp 2475 -2 496 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes descripteurs IGN] analyse spatio-temporelle
[Termes descripteurs IGN] données issues des réseaux sociaux
[Termes descripteurs IGN] données localisées des bénévoles
[Termes descripteurs IGN] espace urbain
[Termes descripteurs IGN] flux de données
[Termes descripteurs IGN] géoétiquetage
[Termes descripteurs IGN] géolocalisation
[Termes descripteurs IGN] hétérogénéité
[Termes descripteurs IGN] Londres
[Termes descripteurs IGN] migration humaine
[Termes descripteurs IGN] modèle de simulation
[Termes descripteurs IGN] modèle orienté agent
[Termes descripteurs IGN] population urbaine
[Termes descripteurs IGN] Tokyo (Japon)
[Termes descripteurs IGN] TwitterRésumé : (auteur) The availability of vast amounts of location-based data from social media platforms such as Twitter has enabled us to look deeply into the dynamics of human movement. The aim of this paper is to leverage a large collection of geo-tagged tweets and the street networks of two major metropolitan areas—London and Tokyo—to explore the underlying mechanism that determines the heterogeneity of human mobility patterns. For the two target cities, hundreds of thousands of tweet locations and road segments were processed to generate city hotspots and natural streets. User movement trajectories and city hotspots were then used to build a hotspot network capable of quantitatively characterizing the heterogeneous movement patterns of people within the cities. To emulate observed movement patterns, the study conducts a two-level agent-based simulation that includes random walks through the hotspot networks and movements in the street networks using each of three distance types—metric, angular and combined. Comparisons of the simulated and observed movement flows at the segment and street levels show that the heterogeneity of human urban movements at the collective level is mainly shaped by the scaling structure of the urban space. Numéro de notice : A2020-692 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/13658816.2020.1718153 date de publication en ligne : 24/01/2020 En ligne : https://doi.org/10.1080/13658816.2020.1718153 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96233
in International journal of geographical information science IJGIS > vol 34 n° 12 (December 2020) . - pp 2475 -2 496[article]A comparison of neighbourhood relations based on ordinary Delaunay diagrams and area Delaunay diagrams: an application to define the neighbourhood relations of buildings / Hiroyuki Usui in International journal of geographical information science IJGIS, vol 34 n° 11 (November 2020)
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Titre : A comparison of neighbourhood relations based on ordinary Delaunay diagrams and area Delaunay diagrams: an application to define the neighbourhood relations of buildings Type de document : Article/Communication Auteurs : Hiroyuki Usui, Auteur ; Akihiro Teraki, Auteur ; Kei-ichi Okunuki, Auteur ; et al., Auteur Année de publication : 2020 Article en page(s) : pp 2177 - 2203 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes descripteurs IGN] adjacence
[Termes descripteurs IGN] analyse de groupement
[Termes descripteurs IGN] ArcGIS
[Termes descripteurs IGN] bâtiment
[Termes descripteurs IGN] chevauchement
[Termes descripteurs IGN] diagramme de Voronoï
[Termes descripteurs IGN] Tokyo (Japon)
[Termes descripteurs IGN] triangulation de Delaunay
[Termes descripteurs IGN] voisinage (topologie)Résumé : (auteur) The aim of this article is to describe a convenient but robust method for defining neighbourhood relations among buildings based on ordinary Delaunay diagrams (ODDs) and area Delaunay diagrams (ADDs). ODDs and ADDs are defined as a set of edges connecting the generators of adjacent ordinary Voronoi cells (points representing centroids of building polygons) and a set of edges connecting two centroids of building polygons, which are the generators of adjacent area Voronoi cells, respectively. Although ADDs are more robust than ODDs, computation time of ODDs is shorter than that of ADDs (the order of their computation time complexity is O(nlogn)). If ODDs can approximate ADDs with a certain degree of accuracy, the former can be used as an alternative. Therefore, we computed the ratio of the number of ADD edges to that of ODD edges overlapping ADDs at building and regional scales. The results indicate that: (1) for approximately 60% of all buildings, ODDs can exactly overlap ADDs with extra ODD edges; (2) at a regional scale, ODDs can overlap approximately 90% of ADDs with 10% extra ODD edges; and (3) focusing on judging errors, although ADDs are more accurate than ODDs, the difference is only approximately 1%. Numéro de notice : A2020-616 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/13658816.2020.1748191 date de publication en ligne : 15/04/2020 En ligne : https://doi.org/10.1080/13658816.2020.1748191 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95991
in International journal of geographical information science IJGIS > vol 34 n° 11 (November 2020) . - pp 2177 - 2203[article]GEBCO Gridded Bathymetric Datasets for mapping Japan Trench geomorphology by means of GMT scripting toolset / Polina Lemenkova in Geodesy and cartography, vol 46 n° 3 (October 2020)
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Titre : GEBCO Gridded Bathymetric Datasets for mapping Japan Trench geomorphology by means of GMT scripting toolset Type de document : Article/Communication Auteurs : Polina Lemenkova, Auteur Année de publication : 2020 Article en page(s) : pp 98 - 112 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Cartographie thématique
[Termes descripteurs IGN] carte bathymétrique
[Termes descripteurs IGN] déformation de la croute terrestre
[Termes descripteurs IGN] données bathymétriques
[Termes descripteurs IGN] données maillées
[Termes descripteurs IGN] geoïde marin
[Termes descripteurs IGN] géomorphologie
[Termes descripteurs IGN] GMT
[Termes descripteurs IGN] Japon
[Termes descripteurs IGN] modèle numérique de surface
[Termes descripteurs IGN] Pacifique (océan)Résumé : (auteur) The study investigated geomorphology of the Japan Trench located east of Japan, Pacific Ocean. A high-resolution GEBCO Gridded Bathymetric Dataset was used for modeling, mapping and visualization. The study aimed to compare and analyse variations in the geomorphic structures of the two parts of the trench and to visualize variations in the geological, geophysical and bathymetric settings. Technically, the cartographic work was performed using scripting based on the Generic Mapping Toolset (GMT). Modelled cross-sectioning orthogonal profiles transecting the trench in a perpendicular direction were automatically digitized and graphed in the two segments. The results of the bathymetric analysis shown that the southern part is shallower: with deeper values in absolute (139 samples between –7000 to –8000 m) and statistical records (the most frequent values are within –5500 to –5800 m) comparing to the northern segment (–5300 to –5500 m). The geomorphological analysis shows a more complicated relief in the northern part of the trench, which has a higher seismic activity. The southern part has a gentler slope on the Honshu island side. The geoid modeling along the trench ranges in 0–20 mGal. The highest values are recorded by the Honshu Island (>40 mGal). The rest of the area has rather moderate undulations (20–40 mGal). The free-air marine gravity of the Sea of Japan is Numéro de notice : A2020-782 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.3846/gac.2020.11524 date de publication en ligne : 08/10/2020 En ligne : https://doi.org/10.3846/gac.2020.11524 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96477
in Geodesy and cartography > vol 46 n° 3 (October 2020) . - pp 98 - 112[article]Prediction of RTK positioning integrity for journey planning / A. El-Mowafy in Journal of applied geodesy, vol 14 n° 4 (October 2020)
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Titre : Prediction of RTK positioning integrity for journey planning Type de document : Article/Communication Auteurs : A. El-Mowafy, Auteur ; Nobuaki Kubo, Auteur Année de publication : 2020 Article en page(s) : pp 431 – 443 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes descripteurs IGN] gestion des itinéraires
[Termes descripteurs IGN] modèle 3D de l'espace urbain
[Termes descripteurs IGN] modèle de simulation
[Termes descripteurs IGN] planification
[Termes descripteurs IGN] positionnement cinématique en temps réel
[Termes descripteurs IGN] positionnement par GNSS
[Termes descripteurs IGN] Receiver Autonomous Integrity Monitoring
[Termes descripteurs IGN] système de transport intelligent
[Termes descripteurs IGN] Tokyo (Japon)
[Termes descripteurs IGN] trajetRésumé : (auteur) Positioning integrity is crucial for Intelligent Transport Systems (ITS) applications. In this article, a method is presented for prediction of GNSS positioning integrity for ITS journey planning. This information, in addition to other route information, such as distance and time, can be utilized to choose the safest and economical route. We propose to combine the Advanced Receiver Autonomous Integrity Monitoring (ARAIM) technique, tailored for ITS, with 3D city models. Positioning is performed by GNSS Real-Time Kinematic (RTK) method, which can provide the accuracy required for ITS. A new threat model employed for computation of the protection levels (PLs) for RTK positioning is discussed. Demonstration of the proposed approach is performed through a kinematic test in an urban area in Tokyo. The comparison between the prediction method and the actual observations show that the two estimate close satellite geometry and PLs. The method produced PLs that bounds the actual position errors all the time and they were less than the preset alert limit. Numéro de notice : A2020-678 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1515/jag-2020-0038 date de publication en ligne : 20/10/2020 En ligne : https://doi.org/10.1515/jag-2020-0038 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96174
in Journal of applied geodesy > vol 14 n° 4 (October 2020) . - pp 431 – 443[article]Application of UAV photogrammetry with LiDAR data to facilitate the estimation of tree locations and DBH values for high-value timber species in Northern Japanese mixed-wood forests / Kyaw Thu Moe in Remote sensing, vol 12 n° 17 (September 2020)
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Titre : Application of UAV photogrammetry with LiDAR data to facilitate the estimation of tree locations and DBH values for high-value timber species in Northern Japanese mixed-wood forests Type de document : Article/Communication Auteurs : Kyaw Thu Moe, Auteur ; Toshiaki Owari, Auteur ; Naoyuki Furuya, Auteur ; et al., Auteur Année de publication : 2020 Article en page(s) : 19 p. Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes descripteurs IGN] aménagement forestier
[Termes descripteurs IGN] analyse d'image orientée objet
[Termes descripteurs IGN] classification par forêts aléatoires
[Termes descripteurs IGN] couvert forestier
[Termes descripteurs IGN] diamètre à hauteur de poitrine
[Termes descripteurs IGN] données lidar
[Termes descripteurs IGN] image captée par drone
[Termes descripteurs IGN] Japon
[Termes descripteurs IGN] orthophotographie
[Termes descripteurs IGN] peuplement mélangé
[Termes descripteurs IGN] photogrammétrie aérienne
[Termes descripteurs IGN] semis de pointsRésumé : (auteur) High-value timber species play an important economic role in forest management. The individual tree information for such species is necessary for practical forest management and for conservation purposes. Digital aerial photogrammetry derived from an unmanned aerial vehicle (UAV-DAP) can provide fine spatial and spectral information, as well as information on the three-dimensional (3D) structure of a forest canopy. Light detection and ranging (LiDAR) data enable area-wide 3D tree mapping and provide accurate forest floor terrain information. In this study, we evaluated the potential use of UAV-DAP and LiDAR data for the estimation of individual tree location and diameter at breast height (DBH) values of large-size high-value timber species in northern Japanese mixed-wood forests. We performed multiresolution segmentation of UAV-DAP orthophotographs to derive individual tree crown. We used object-based image analysis and random forest algorithm to classify the forest canopy into five categories: three high-value timber species, other broadleaf species, and conifer species. The UAV-DAP technique produced overall accuracy values of 73% and 63% for classification of the forest canopy in two forest management sub-compartments. In addition, we estimated individual tree DBH Values of high-value timber species through field survey, LiDAR, and UAV-DAP data. The results indicated that UAV-DAP can predict individual tree DBH Values, with comparable accuracy to DBH prediction using field and LiDAR data. The results of this study are useful for forest managers when searching for high-value timber trees and estimating tree size in large mixed-wood forests and can be applied in single-tree management systems for high-value timber species. Numéro de notice : A2020-597 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.3390/rs12172865 date de publication en ligne : 03/09/2020 En ligne : https://doi.org/10.3390/rs12172865 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95942
in Remote sensing > vol 12 n° 17 (September 2020) . - 19 p.[article]Shoreline extraction from WorldView2 satellite data in the presence of foam pixels using multispectral classification method / Audrey Minghelli in Remote sensing, vol 12 n° 16 (August 2020)
PermalinkCombination of linear regression lines to understand the response of Sentinel-1 dual polarization SAR data with crop phenology - case study in Miyazaki, Japan / Emal Wali in Remote sensing, vol 12 n° 1 (January 2020)
PermalinkHigh‐resolution national land use scenarios under a shrinking population in Japan / Haruka Ohashi in Transactions in GIS, vol 23 n° 4 (August 2019)
PermalinkVGI contributors’ awareness of geographic information quality and its effect on data quality: a case study from Japan / Jun Yamashita in International journal of cartography, vol 5 n° 2-3 (July - November 2019)
PermalinkMonitoring suspended particle matter using GOCI satellite data after the Tohoku (Japan) tsunami in 2011 / Audrey Minghelli in IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, vol 12 n° 2 (February 2019)
PermalinkConstruction of the Japan Gravity Standardization Net 2016 / Toshihiro Yahagi in Bulletin of the GeoSpatial Information authority of Japan, vol 66 (November 2018)
PermalinkImprovement of countrywide vegetation mapping over Japan and comparison to existing maps / Ram C. Sharma in Advances in Remote Sensing, vol 7 n° 3 (September 2018)
PermalinkA two-stage estimation method with bootstrap inference for semi-parametric geographically weighted generalized linear models / Dengkui Li in International journal of geographical information science IJGIS, vol 32 n° 9-10 (September - October 2018)
PermalinkMigrating pattern of deformation prior to the Tohoku-Oki earthquake revealed by GRACE data / Isabelle Panet in Nature geoscience, vol 11 n° 5 (May 2018)
PermalinkA comparative approach to modelling multiple urban land use changes using tree-based methods and cellular automata: the case of Greater Tokyo Area / Guodong Du in International journal of geographical information science IJGIS, vol 32 n° 3-4 (March - April 2018)
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