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Auteur M. Yuan |
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Assessing spatial uncertainty of LIDAR-derived building model: a case study in downtown Oklahoma city / M. Cheuk in Photogrammetric Engineering & Remote Sensing, PERS, vol 75 n° 3 (March 2009)
[article]
Titre : Assessing spatial uncertainty of LIDAR-derived building model: a case study in downtown Oklahoma city Type de document : Article/Communication Auteurs : M. Cheuk, Auteur ; M. Yuan, Auteur Année de publication : 2009 Article en page(s) : pp 257 - 269 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] données lidar
[Termes IGN] estimation de précision
[Termes IGN] incertitude géométrique
[Termes IGN] milieu urbain
[Termes IGN] modèle numérique du bâti
[Termes IGN] Oklahoma (Etats-Unis)
[Termes IGN] reconstruction 3D du bâtiRésumé : (Auteur) Light Detection and Ranging (lidar) technology enables cost-effective rapid production of digital models that capture topography and vertical structures of surface features at a fine spatial resolution. The capability has promoted lidar applications for mapping terrain, buildings, forest stands, and coastal features that cannot be adequately captured by other remote sensing means over a large area. However, in complex terrain, lidar data and lidar-derived products may contain significant uncertainty. This research provides a simple method to assess the spatial uncertainty of lidar-derived building model, using downtown Oklahoma City, Oklahoma as an example. Results indicate that significant uncertainty could be found in urban environment where: (a) building structures are complex, (b) buildings are constructed with reflective materials, and (c) vegetation grows near-by. In addition, cities under rapid development also challenge the accuracy assessment of 3D building models. To conclude, we suggest: (a) careful pre-flight planning before data collection, (b) improve the feature extraction algorithm if possible, (c) use of other remote sensing data, and (d) accuracy assessment on suggested urban environments to reduce the spatial uncertainty of lidar data and lidar-derived products. Copyright ASPRS Numéro de notice : A2009-036 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.75.3.257 En ligne : https://doi.org/10.14358/PERS.75.3.257 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29666
in Photogrammetric Engineering & Remote Sensing, PERS > vol 75 n° 3 (March 2009) . - pp 257 - 269[article]Towards a general theory of geographic representation in GIS / Michael F. Goodchild in International journal of geographical information science IJGIS, vol 21 n° 3-4 (march - april 2007)
[article]
Titre : Towards a general theory of geographic representation in GIS Type de document : Article/Communication Auteurs : Michael F. Goodchild, Auteur ; M. Yuan, Auteur ; T.J. Cova, Auteur Année de publication : 2007 Article en page(s) : pp 239 - 260 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] continuité géographique
[Termes IGN] discrétisation
[Termes IGN] modèle conceptuel de données localisées
[Termes IGN] modèle orienté objet
[Termes IGN] objet géographique
[Termes IGN] quantité continue
[Termes IGN] quantité discrète
[Termes IGN] représentation continueRésumé : (Auteur) Geographic representation has become more complex through time as researchers have added new concepts, leading to apparently endless proliferation and creating a need for simplification. We show that many of these concepts can be derived from a single foundation that we term the atomic form of geographic information. The familiar concepts of continuous fields and discrete objects can be derived under suitable rules applied to the properties and values of the atomic form. Fields and objects are further integrated through the concept of phase space, and in the form of field objects. A second atomic concept is introduced, termed the geo-dipole, and shown to provide a foundation for object fields, metamaps, and the association classes of object-oriented data modelling. Geographic dynamics are synthesized in a three-dimensional space defined by static or dynamic object shape, the possibility of movement, and the possibility of dynamic internal structure. The atomic form also provides a tentative argument that discrete objects and continuous fields are the only possible bases for geographic representation. Copyright Taylor & Francis Numéro de notice : A2007-110 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article DOI : 10.1080/13658810600965271 En ligne : https://doi.org/10.1080/13658810600965271 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28473
in International journal of geographical information science IJGIS > vol 21 n° 3-4 (march - april 2007) . - pp 239 - 260[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-07021 RAB Revue Centre de documentation En réserve L003 Disponible 079-07022 RAB Revue Centre de documentation En réserve L003 Disponible A framework to enhance semantic flexibility for analysis of distributed phenomena / J Mcintosh in International journal of geographical information science IJGIS, vol 19 n° 10 (november 2005)
[article]
Titre : A framework to enhance semantic flexibility for analysis of distributed phenomena Type de document : Article/Communication Auteurs : J Mcintosh, Auteur ; M. Yuan, Auteur Année de publication : 2005 Article en page(s) : pp 999 - 1018 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] analyse d'image orientée objet
[Termes IGN] analyse spatiale
[Termes IGN] distribution spatiale
[Termes IGN] données maillées
[Termes IGN] données vectorielles
[Termes IGN] information sémantique
[Termes IGN] modèle conceptuel de données spatio-temporelles
[Termes IGN] modèle logique de données
[Termes IGN] problème des valeurs limites
[Termes IGN] représentation des détails topographiques
[Termes IGN] représentation multiple
[Termes IGN] requête spatiotemporelle
[Termes IGN] seuillage
[Termes IGN] système d'information géographique
[Termes IGN] varianceRésumé : (Auteur) While some geographic phenomena hold uniform properties, such as land-use zones, many geographic phenomena are distributed such that their properties vary across an extended area. While such distributed phenomena are best represented as continuous surfaces, individual objects (or features) often emerge among clusters of high or low values in a field. For example, areas of relatively high elevation may be viewed as hills, while flat low-lying areas are perceived as plains in a terrain. A comprehensive spatial analysis of distributed phenomena should examine both the spatial variance of its attribute surfaces and the characteristics of individual objects embedded in the field. An immediate research challenge to meet such spatial analysis needs is that these emerging features often have vague boundaries that vary according to the use and the user. The nature, and even existence, of these objects depend upon the range of values, or thresholds, used to define them. We propose a representation framework that takes a dual raster-vector approach to capture both field- and object-like characteristics of distributed phenomena and maintain multiple representations of embedded features delineated by boundaries that are likely to be relevant for the expected uses of the data. We demonstrate how boundaries influence the analysis and understanding of spatiotemporal characteristics of distributed phenomena. Using precipitation as a proof of concept, we show how the proposed framework enhances semantic flexibility in spatiotemporal query and analysis of distributed phenomena in geographic information systems. Numéro de notice : A2005-496 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/13658810500197652 En ligne : https://doi.org/10.1080/13658810500197652 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27632
in International journal of geographical information science IJGIS > vol 19 n° 10 (november 2005) . - pp 999 - 1018[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-05091 RAB Revue Centre de documentation En réserve L003 Disponible 079-05092 RAB Revue Centre de documentation En réserve L003 Disponible Representing complex geographic phenomena in GIS / M. Yuan in Cartography and Geographic Information Science, vol 28 n° 2 (April 2001)
[article]
Titre : Representing complex geographic phenomena in GIS Type de document : Article/Communication Auteurs : M. Yuan, Auteur Année de publication : 2001 Article en page(s) : pp 83 - 96 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] données spatiotemporelles
[Termes IGN] modèle conceptuel de données
[Termes IGN] modèle orienté objet
[Termes IGN] Oklahoma (Etats-Unis)
[Termes IGN] phénomène météorologique
[Termes IGN] précipitation
[Termes IGN] processus
[Termes IGN] représentation géographique
[Termes IGN] requête spatiotemporelle
[Termes IGN] système d'information géographiqueRésumé : (Auteur) Conventionally, spatial data models have been designed according to object- or field-based conceptualizations of reality. Conceptualization of complex geographic phenomena that have both object and field-like properties, such as wildfire and precipitation, has not yet been incorporated into GIS data models. To this end, a new conceptual framework is proposed in this research for organizing data about such complex geographic phenomena in a GIS as a hierarchy of events, processes, and states. In this framework, discrete objects are used to show how events and processes progress in space and time, and fields are used to model how states of geographic themes vary in a space-time frame. Precipitation is used to demonstrate the construction and application of the proposed framework with digital precipitation data from April 15 to May 22, 1998, for the state of Oklahoma, U.S.A. With the proposed framework, two sets of algorithms have been developed. One set automatically assembles precipitation events and processes from the data and stores the precipitation data in the hierarchy of events, processes, and states, so that attributes about events, processes, and states are readily available for information query. The other set of algorithms computes information about the spatio-temporal behavior and interaction of events and processes. The proposed approach greatly enhances support for complex spatio-temporal queries on the behavior and relationships of events and processes. Numéro de notice : A2001-098 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article DOI : 10.1559/152304001782173718 En ligne : https://doi.org/10.1559/152304001782173718 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=21798
in Cartography and Geographic Information Science > vol 28 n° 2 (April 2001) . - pp 83 - 96[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 032-01021 RAB Revue Centre de documentation En réserve L003 Disponible