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37.00 Géomatique - information géographique - infrastructure de donnéesOuvrages de la bibliothèque en indexation 37.70 (5)
Ajouter le résultat dans votre panier Affiner la recherche Interroger des sources externesNovel drawing algorithms and application of texture mapping for 2D cartographic line symbolization / Fei He (2008)
Titre : Novel drawing algorithms and application of texture mapping for 2D cartographic line symbolization Type de document : Thèse/HDR Auteurs : Fei He, Auteur ; Lorenz Hurni, Directeur de thèse Editeur : Zurich : Eidgenossische Technische Hochschule ETH - Ecole Polytechnique Fédérale de Zurich EPFZ Année de publication : 2008 Collection : Dissertationen ETH num. 17439 Importance : 167 p. Format : 15 x 20 cm Note générale : bibliographie
A dissertation submitted to ETH Zurich for the degree of doctor of sciencesLangues : Anglais (eng) Descripteur : [Termes IGN] figuré linéaire
[Termes IGN] objet géographique linéaire
[Termes IGN] symbole graphique
[Termes IGN] texturage
[Vedettes matières IGN] GénéralisationIndex. décimale : 37.70 Généralisation Résumé : (auteur) A high quality map is characterized by the appropriate presentation of the basic graphic elements, including points, lines and areas. At present, most of the commonly used graphic software was designed for general purpose of digital image production; many cartographic principles are not completely satisfied. As a result, a time-consuming modification work is typically required for a convincing cartographic product.
In this thesis, two approaches were studied to improve this situation by focusing on one graphic element, the line. The first approach is dealing with cartographic elaborations of line geometries. New drawing algorithms were developed to generate lines better satisfying the cartographic requirements. Many unsatisfied presentations that often occur at line ends, turns and intersections, can be avoided during the rendering process.
The second approach aims to enrich the line symbols, covering both categories and visual qualities. First, efficient drawing methods were developed to draw some complex lines, including both single and multiple lines. Second, the computer graphic technique of texture mapping was the first time introduced into cartography; which turns out to be an interesting tool to greatly improve line symbolizations. These achievements lead to the production of a new program, SmartLine. It contains a flexible editorial environment, allowing map makers to adjust the graphic attributes of line symbols easily. This work aims to improve the generation of line symbols, which is not only useful for cartographers but also for general users of the interactive map products.Numéro de notice : 17193 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Thèse étrangère Note de thèse : Doctoral dissertation : Sciences : ETH Zurich : 2008 En ligne : http://e-collection.library.ethz.ch/view/eth:30768?q=fei%20he Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81160 Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 17193-01 37.70 Livre Centre de documentation Géomatique Disponible
Titre : An optimisation approach to cartographic generalisation : doctoral thesis Type de document : Thèse/HDR Auteurs : Lars Harrie, Auteur Editeur : Lund [Suède] : Lund University Année de publication : 2001 Importance : 196 p. Format : 16 x 23 cm ISBN/ISSN/EAN : 978-91-628-4652-7 Note générale : bibliographie
Doctoral thesisLangues : Français (fre) Descripteur : [Termes IGN] base de données orientée objet
[Termes IGN] contrainte de cohérence
[Termes IGN] contrainte géométrique
[Termes IGN] généralisation cartographique
[Termes IGN] généralisation cartographique automatisée
[Termes IGN] méthode des moindres carrés
[Termes IGN] mise à jour de base de données
[Termes IGN] optimisation (mathématiques)
[Termes IGN] programmation par contraintes
[Termes IGN] représentation multiple
[Vedettes matières IGN] GénéralisationIndex. décimale : 37.70 Généralisation Résumé : (auteur) Cartographic generalisation is the process of simplifying a representation to suit the scale and purpose of a map. As such, generalisation has always been a central part in map production. This thesis is a contribution to the ongoing work on automating cartographic generalisation. Two topics are treated: optimisation methods in graphic generalisation, and propagation of updates between cartographic data sets of different scales. To enable an optimisation approach to graphic generalisation several topics are studied. Firstly, requirements are stated for defining a good map. These requirements can act as constraints and control the graphic generalisation process. In this thesis, ten analytical constraints for graphic generalisation are proposed, some for single objects and some for groups of objects. Rules are also established regarding when these constraints should be set up. Secondly, the least-squares method is studied as an approach to finding the optimal solution according to the constraints. Related to this, weighting strategies for the constraints are also discussed. Thirdly, computationally efficient methods are tested, which are especially important for establishing spatial relationships between objects and solving the large normal equation systems. Finally, the optimisation approach has been evaluated visually and quantitatively in mid-scale applications. Mapping organisations have to maintain cartographic data sets of different scales (resolutions). Ideally, mapping organisations should only be concerned with updating the most detailed data set and the updates should automatically be propagated to all other data sets. In this study, a prototype system was created for automatic propagation of updates. This system is integrated in an object-oriented map production software, in which the data sets are stored in a multiple representation database. The rules implemented in the prototype system were gathered from data set specifications and by studying printed map series. The propagation of updates performed by the prototype system was compared with manual propagation performed by a cartographer. Note de contenu : 1- Introduction
2- Cartographic generalisation concepts
3- Spatial concepts
4- Review of generalisation research
5- Summary of the papersNuméro de notice : 17192 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Thèse étrangère Note de thèse : Doctoral thesis : Surveying : Lund University : 2001 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81159 Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 17192-01 37.70 Livre Centre de documentation Géomatique Disponible Mécanismes de coordination multi-agents pour la cartographie automatique : Analyse d'un problème spatialisé complexe / Cécile Duchêne (2001)
Titre : Generalisation methods for propagating updates between cartographic data sets : Licentiate thesis Type de document : Mémoire Auteurs : Lars Harrie, Auteur Editeur : Lund [Suède] : Lund University Année de publication : 1998 Importance : 127 p. Format : 15 x 21 cm ISBN/ISSN/EAN : 978-91-630-7502-5 Note générale : Bibliographie
Licentiate thesisLangues : Anglais (eng) Descripteur : [Termes IGN] algorithme de Douglas-Peucker
[Termes IGN] B-Spline
[Termes IGN] filtre de Gauss
[Termes IGN] généralisation cartographique
[Termes IGN] Lamps2
[Termes IGN] modèle (conceptuel) de généralisation
[Termes IGN] opérateur de généralisation
[Termes IGN] programmation par contraintes
[Termes IGN] prototype
[Termes IGN] relation topologique
[Termes IGN] représentation multiple
[Vedettes matières IGN] GénéralisationIndex. décimale : 37.70 Généralisation Résumé : (Auteur) Automation is increasingly important in producing and maintaining cartographic data sets. This thesis deals with automatic methods to propagate updates between cartographic data sets. The major idea is to update only the most detailed data set (master data set) and then propagate these updates automatically to less detailed data sets (target data sets). The approach used is firstly to formulate linguistic rules for the update process. The information sources for these linguistic rules are data set specifications, cartographic data sets, paper maps and practising cartographers. These linguistic rules are translated into logical rules and then implemented in a prototype system. The prototype system is built on top of an object-oriented map production software. The system requires a multiple representation database, which consists of cartographic data sets at different scales together with connectivities between those objects that refer to the same physical entities. The prototype system is built on a conceptual framework of four steps: examination, propagation, generalisation of updates and solving spatial conflicts. The aim of the examination step is to determine which object should be created, modified or deleted in the target data set. The action is dependent on the current status of the target data set and the properties of the update to the master data set. The propagation step executes the outcome of the examination step. Furthermore, this step validates the updates and maintains the integrity of the multiple representation databas6. In the next step — generalisation of updates — the new or modified object in the target data set is generalised to suit the scale of the target data set. The final step treats spatial conflicts due to the update. A new method is proposed for solving spatial conflicts, called the constraint method, which is a generic method that resembles manual generalisation on a conceptual level. Note de contenu : 1 - Cartographic concepts
2 - Spatial concepts
3 - Previous work on generalisation
4 - The constraint method
5 - Prototype system of incremental generalisation
6 - Discussion and concluding remarksNuméro de notice : 21509 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Mémoire licence Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=90349 Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 21509-01 37.70 Livre Centre de documentation Géomatique Disponible
Titre : Displacement as the most powerful indicator of map generalisation Type de document : Rapport Auteurs : Elsa Maria Joao, Auteur Editeur : Londres [Royaume-Uni] : London School of Economics Année de publication : 1996 Collection : Research Papers in Environmental and Spatial analysis num. 28 Importance : 23 p. Format : 14 x 21 cm ISBN/ISSN/EAN : 978-0-7530-0693-1 Langues : Anglais (eng) Descripteur : [Termes IGN] déplacement d'objet géographique
[Termes IGN] erreur de positionnement
[Termes IGN] généralisation cartographique
[Termes IGN] indicateur de qualité
[Termes IGN] qualité de généralisation
[Termes IGN] qualité des données
[Termes IGN] système d'information géographique
[Vedettes matières IGN] GénéralisationIndex. décimale : 37.70 Généralisation Résumé : (auteur) Generalisation is important to Geographical Information Systems (GIS), not only because of the drive towards automating the process, but also because generalisation can seriously affect data quality within spatial databases. Based on the results of an empirical study, this paper presents evidence that among the different types of generalisation effects, displacement is the most powerful indicator of cartographic generalisation. In order to evaluate the significance of displacement as caused by generalisation, a 'cut-off-point' is calculated beyond which the positional error is more likely to be due to generalisation rather than other sources of error affecting positional accuracy. It is found that for all features studied there were local displacements superior to the cut-off-point. The general importance of displacement is also discussed. Note de contenu : Introduction
1- The impact of generalisation on data quality
2- Separating generalisation effects from ther sources of error
3- Evaluating displacement caused by generalisation
ConclusionsNuméro de notice : 21912 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Rapport de recherche Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91574 Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 21912-01 39.20 Livre Centre de documentation Géomatique Disponible
