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An integrated approach to the generalization of geological maps / T.C. Downs in Cartographic journal (the), vol 39 n° 2 (December 2002)  

Public [article]  inCartographic journal (the) > vol 39 n° 2 (December 2002) . - pp 137 - 152 Titre : An integrated approach to the generalization of geological maps Type de document : Article/Communication Auteurs : T.C. Downs, Auteur ; William A Mackaness, Auteur Année de publication : 2002 Article en page(s) : pp 137 - 152 Langues : Anglais (eng) Descripteur : [Termes IGN] base de données multi-représentation [Termes IGN] carte géologique [Termes IGN] cartographie géologique [Termes IGN] cohérence des données [Termes IGN] généralisation cartographique automatisée [Termes IGN] réalité de terrain [Vedettes matières IGN] Généralisation Résumé : (Auteur) The British Geological Survey is recognizing the consumer's need for customized 'builtforpurpose'geoscientific data sets. It is witnessing a move away from being merely producers of standard scale cartographic products. This research proposes an automated tool for the generalization of geological maps, which may assist the organization in meeting these demands. The research shows that in order to derive a coarse scale geological map from a fine scale geological database there is a requirement for contextual sensitivity. To achieve an appropriate result the interaction between the themes represented on the map must be considered and should reflect the interaction of geological objects in the real world. A case study is presented which illustrates how standard cartographic generalization operations can be combined, using a rule base, into a partially automated process to generalize a geological data set from 1.50 000 to 1.250 000 scale. Independent geoscientific professionals evaluated the results from the case study. The tool provides consistency and tracabilty in the generation of multiscale geoscientific data. The evaluation suggests that, with further research, higher levels of autonomous generalization are achievable. In its current form it is a highly useful tool as a testbed for defining generalization requirements in geological mapping, an aid to the production of standard scale maps and a basis for creating customer specific data sets. Numéro de notice : A2002-311 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1179/caj.2002.39.2.137 En ligne : https://www.tandfonline.com/doi/abs/10.1179/caj.2002.39.2.137 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=22222 [article]

Exemplaires(1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
030-02021	RAB	Revue	Centre de documentation	En réserve L003	Disponible

Topographic map generalization: association of road elimination with thematic attributes / Z. Li in Cartographic journal (the), vol 39 n° 2 (December 2002)  

Public [article]  inCartographic journal (the) > vol 39 n° 2 (December 2002) . - pp 153 - 166 Titre : Topographic map generalization: association of road elimination with thematic attributes Type de document : Article/Communication Auteurs : Z. Li, Auteur ; Y.H. Choi, Auteur Année de publication : 2002 Article en page(s) : pp 153 - 166 Langues : Anglais (eng) Descripteur : [Termes IGN] agrégation de détails [Termes IGN] attribut [Termes IGN] cartographie topographique [Termes IGN] élimination [Termes IGN] généralisation cartographique automatisée [Termes IGN] géocodage [Termes IGN] Hong-Kong [Termes IGN] objet géographique linéaire [Termes IGN] réseau routier [Vedettes matières IGN] Généralisation Résumé : (Auteur) It has been widely recognized that, in order to automate the map generalization process, cartographic knowledge needs to be formalized. One method of knowledge acquisition is to analyse existing maps. Previous studies have concentrated on describing the phenomena on the surface. A typical example is the percentage change of the number of symbols or the percentage of open space on smaller scale maps. This study aims to go one step further, i.e. to analyse the association such changes with thematic attributes. In this study, road features on topographic maps of Hong Kong from 1:1000 to 1:200 000 are studied; six types of thematic attributes, i.e. 'type', 'length', 'width', 'number of lanes', 'number of traffic ways' and 'connectivity', are considered; and two statistic parameters, Lambda and Somers' Delta, are employed. It has been discovered that the dependence of road elimination on these attributes occurs in the following order : type (0.73), length (0.53), number of lanes (0.48), number of traffic directions (0.41), width (0.36) and connectivity (0.19). If these numbers are normalized into percentages, then these values become: type (27%), length (20%), number of lanes (18%), number of traffic directions (15%), width (13%) and connectivity (7%). Such results could be used to formulate an overall weight to determine whether a particular road should be deleted, merged or combined in the generalization process, in order to retain a certain proportion of roads at a smaller scale. Numéro de notice : A2002-312 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1179/caj.2002.39.2.153 En ligne : https://www.tandfonline.com/doi/abs/10.1179/caj.2002.39.2.153 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=22223 [article]

Exemplaires(1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
030-02021	RAB	Revue	Centre de documentation	En réserve L003	Disponible