Détail de l'auteur
Auteur H. Yu |
Documents disponibles écrits par cet auteur (3)
Ajouter le résultat dans votre panier Affiner la recherche Interroger des sources externes
Effects of topographic variability and Lidar sampling density on several DEM interpolation methods / Q. Guo in Photogrammetric Engineering & Remote Sensing, PERS, vol 76 n° 6 (June 2010)
[article]
Titre : Effects of topographic variability and Lidar sampling density on several DEM interpolation methods Type de document : Article/Communication Auteurs : Q. Guo, Auteur ; W. Li, Auteur ; H. Yu, Auteur ; O. Alvarez, Auteur Année de publication : 2010 Article en page(s) : pp 701 - 712 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] classification barycentrique
[Termes IGN] densité des points
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] fonction spline d'interpolation
[Termes IGN] interpolation
[Termes IGN] interpolation inversement proportionnelle à la distance
[Termes IGN] krigeage
[Termes IGN] modèle numérique de terrain
[Termes IGN] Triangulated Irregular Network
[Termes IGN] variabilitéRésumé : (Auteur) This study aims to quantify the effects of topographic variability (measured by coefficient variation of elevation, CV) and lidar (Light Detection and Ranging) sampling density on the DEM (Digital Elevation Model) accuracy derived from several interpolation methods at different spatial resolutions. Interpolation methods include natural neighbor (NN), inverse distance weighted (IDW), triangulated irregular network (TIN), spline, ordinary kriging (OK), and universal kriging (UK). This study is unique in that a comprehensive evaluation of the combined effects of three influencing factors (CV, sampling density, and spatial resolution) on lidar-derived DEM accuracy is carried out using different interpolation methods. Results indicate that simple interpolation methods, such as IDW, NN, and TIN, are more efficient at generating DEMs from lidar data, but kriging-based methods, such as OK and UK, are more reliable if accuracy is the most important consideration. Moreover, spatial resolution also plays an important role when generating DEMs from lidar data. Our results could be used to guide the choice of appropriate lidar interpolation methods for DEM generation given the resolution, sampling density, and topographic variability. Numéro de notice : A2010-228 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.76.6.701 En ligne : https://doi.org/10.14358/PERS.76.6.701 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30422
in Photogrammetric Engineering & Remote Sensing, PERS > vol 76 n° 6 (June 2010) . - pp 701 - 712[article]Exploring potential human activities in physical and virtual spaces: a spatio-temporal GIS approach / H. Yu in International journal of geographical information science IJGIS, vol 22 n° 4-5 (april 2008)
[article]
Titre : Exploring potential human activities in physical and virtual spaces: a spatio-temporal GIS approach Type de document : Article/Communication Auteurs : H. Yu, Auteur ; Shih-Lung Shaw, Auteur Année de publication : 2008 Article en page(s) : pp 409 - 430 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes d'information géographique
[Termes IGN] données spatiotemporelles
[Termes IGN] espace-temps
[Termes IGN] monde virtuel
[Termes IGN] SIG 3D
[Termes IGN] Time-geographyRésumé : (Auteur) Today, the opportunity for potential human activity has gone beyond physical space to virtual space. Based on a proposed conceptual framework that models the relationships between physical and virtual spaces, this paper presents an attempt to adjust the space-time prism concept of Haumlgerstrand's time geography to identify potential activity opportunities in virtual space, focusing on the virtual space access channels available in physical space. A three-dimensional (3D) spatio-temporal Geographic Information System (GIS) design has been developed in this research to accommodate the adjusted space-time prism concept to support the representation, visualization, and analysis of potential human activities and interactions in physical and virtual spaces using the prism representation. Following the design, a prototype system has been successfully implemented in a 3D GIS environment. Such a system can provide powerful analytical tools for studies related to potential human activities and applications such as location-based services (LBS) and accessibility analysis in the information age. Copyright Taylor & Francis Numéro de notice : A2008-147 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article DOI : 10.1080/13658810701427569 En ligne : https://doi.org/10.1080/13658810701427569 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29142
in International journal of geographical information science IJGIS > vol 22 n° 4-5 (april 2008) . - pp 409 - 430[article]Réservation
Réserver ce documentExemplaires (2)
Code-barres Cote Support Localisation Section Disponibilité 079-08031 RAB Revue Centre de documentation En réserve L003 Disponible 079-08032 RAB Revue Centre de documentation En réserve L003 Disponible Spatio-temporal GIS design for exploring interactions of human activities / H. Yu in Cartography and Geographic Information Science, vol 33 n° 1 (January 2006)
[article]
Titre : Spatio-temporal GIS design for exploring interactions of human activities Type de document : Article/Communication Auteurs : H. Yu, Auteur Année de publication : 2006 Article en page(s) : pp 3 - 19 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes d'information géographique
[Termes IGN] analyse spatio-temporelle
[Termes IGN] ArcGIS
[Termes IGN] co-positionnement
[Termes IGN] données spatiotemporelles
[Termes IGN] géographie humaine
[Termes IGN] interaction spatiale
[Termes IGN] maladie infectieuse
[Termes IGN] programmation informatique
[Termes IGN] prototype
[Termes IGN] réalité virtuelle
[Termes IGN] sécurité
[Termes IGN] segmentation dynamique
[Termes IGN] système d'information géographique
[Termes IGN] Time-geographyRésumé : (Auteur) An effective representation of human activities in geographic information systems (GIS) presents a challenging research topic. Recent developments of information and communication technologies (ICT), which enable a virtual space and allow people to interact with others remotely, make such efforts even more difficult. This paper first extends the space-time path concept of Hägerstrand's time geography to represent both physical and virtual activities in a space-time context. A spatio-temporal GIS design which can accommodate the extended space-time path concept is proposed to support the exploration of spatio-temporal patterns of human interactions in physical and virtual spaces. Using time as a linear referencing system, a temporal dynamic segmentation method was developed to dynamically locate physical and virtual activities on space-time paths. The GIS design supports the identification of four different spatio-temporal patterns (i.e., co-existence, co-location in space, co-location in time, and no co-location in either space or time) of human interactions through their space-time paths. Using a hypothetical activity dataset, a prototype system is implemented as a three-dimensional GIS (i.e., two-dimensional space + one-dimensional time) in ArcGIS. The prototype system demonstrates the feasibility and potential of applying spatio-temporal GIS concepts to extend Hägerstrand's time-geographic framework for the representation and analysis of human interactions in both physical and virtual spaces. The proposed GIS design can be useful in such applications as understanding traffic congestion, tracking terrorist activities, and modeling the spread of infections diseases. Copyright CAGIS Numéro de notice : A2006-202 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article DOI : 10.1559/152304006777323136 En ligne : https://doi.org/10.1559/152304006777323136 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27929
in Cartography and Geographic Information Science > vol 33 n° 1 (January 2006) . - pp 3 - 19[article]Réservation
Réserver ce documentExemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 032-06011 RAB Revue Centre de documentation En réserve L003 Disponible