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Visualisation of origins, destinations and flows with OD maps / J. Wood in Cartographic journal (the), vol 47 n° 2 (May 2010)  

Public [article]  inCartographic journal (the) > vol 47 n° 2 (May 2010) . - pp 117 - 129 Titre : Visualisation of origins, destinations and flows with OD maps Type de document : Article/Communication Auteurs : J. Wood, Auteur ; A. Slingsby, Auteur ; Jason Dykes, Auteur Année de publication : 2010 Article en page(s) : pp 117 - 129 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géomatique [Termes IGN] arc [Termes IGN] cartographie des flux [Termes IGN] cartographie dynamique [Termes IGN] généralisation cartographique automatisée [Termes IGN] matrice [Termes IGN] migration humaine [Termes IGN] trajectographie (positionnement) [Termes IGN] visualisation cartographique [Termes IGN] visualisation de données Résumé : (Auteur) We present a new technique for the visual exploration of origins (O) and destinations (D) arranged in geographic space. Previous attempts to map the flows between origins and destinations have suffered from problems of occlusion usually requiring some form of generalisation, such as aggregation or flow density estimation before they can be visualized. This can lead to loss of detail or the introduction of arbitrary artefacts in the visual representation. Here, we propose mapping OD vectors as cells rather than lines, comparable with the process of constructing OD matrices, but unlike the OD matrix, we preserve the spatial layout of all origin and destination locations by constructing a gridded two-level spatial treemap. The result is a set of spatially ordered small multiples upon which any arbitrary geographic data may be projected. Using a hash grid spatial data structure, we explore the characteristics of the technique through a software prototype that allows interactive query and visualisation of 105-106 simulated and recorded OD vectors. The technique is illustrated using US county to county migration and commuting statistics. Copyright British Cartographic Society Numéro de notice : A2010-258 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1179/000870410X12658023467367 Date de publication en ligne : 18/07/2013 En ligne : https://doi.org/10.1179/000870410X12658023467367 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30452 [article]

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Higher order vagueness in geographical information: empirical geographical population of type N fuzzy sets / P. Fischer in Geoinformatica, vol 11 n° 3 (September - November 2007)  

Public [article]  inGeoinformatica > vol 11 n° 3 (September - November 2007) . - pp 311 - 330 Titre : Higher order vagueness in geographical information: empirical geographical population of type N fuzzy sets Type de document : Article/Communication Auteurs : P. Fischer, Auteur ; T. Cheng, Auteur ; J. Wood, Auteur Année de publication : 2007 Article en page(s) : pp 311 - 330 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image [Termes IGN] analyse discriminante [Termes IGN] classification floue [Termes IGN] détection de contours [Termes IGN] Ecosse [Termes IGN] géomorphologie locale [Termes IGN] imprécision géométrique [Termes IGN] sous ensemble flou Résumé : (Auteur) Fuzzy set theory has been suggested as a means for representing vague spatial phenomena, and is widely known for directly addressing some of the issues of vagueness such as the sorites paradox. Higher order vagueness is widely considered a necessary component of any theory of vagueness, but it is not so well known that it too is competently modelled by Type n Fuzzy sets. In this paper we explore the fuzzy representation of higher order vagueness with respect to spatial phenomena. Initially we relate the arguments on philosophical vagueness to Type n Fuzzy sets. As an example, we move on to an empirical generation of spatial Type 2 Fuzzy sets examining the spatial extent of mountain peaks in Scotland. We show that the Type 2 Fuzzy sets can be populated by using alternative parameterisations of a peak detection algorithm. Further ambiguities could also be explored using other parameters of this and other algorithms. We show some novel answers to interrogations of the mountain peaks of Scotland. The conclusion of this work is that higher order vagueness can be populated for Type 2 and higher fuzzy sets. It does not follow that it is always necessary to examine these higher order uncertainties, but a possible advantage in terms of the results of spatial inquiry is demonstrated. Copyright Springer Numéro de notice : A2007-379 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1007/s10707-006-0009-5 En ligne : https://doi.org/10.1007/s10707-006-0009-5 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28742 [article]

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057-07031	RAB	Revue	Centre de documentation	En réserve L003	Disponible