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Spatial objects / R. Thompson in GIM international, vol 22 n° 7 (July 2008)
[article]
Titre : Spatial objects Type de document : Article/Communication Auteurs : R. Thompson, Auteur ; Peter J. M. Van Oosterom, Auteur Année de publication : 2008 Article en page(s) : pp 23 - 27 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] base de données localisées
[Termes IGN] cohérence des données
[Termes IGN] coordonnées cartésiennes géocentriques
[Termes IGN] normalisation
[Termes IGN] objet géographique 3D
[Termes IGN] objet géographique complexe
[Termes IGN] polyèdre convexe
[Termes IGN] polytope
[Termes IGN] représentation vectorielle
[Termes IGN] spécification de produit
[Termes IGN] validité des donnéesRésumé : (Auteur) With the expending use of spatial information comes a growing need to interchange this information. Parallel runs of development of spatial databases serving multiple applications. Both have highlighted the need for consistency of representation and behaviour of spatial objects across computing platforms. Copyright Reed Business Information Numéro de notice : A2008-219 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29214
in GIM international > vol 22 n° 7 (July 2008) . - pp 23 - 27[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 061-08071 SL Revue Centre de documentation Revues en salle Disponible A simplicial complex-based DBMS approach to 3D topographic data modelling / F. Penninga in International journal of geographical information science IJGIS, vol 22 n° 6-7 (june 2008)
[article]
Titre : A simplicial complex-based DBMS approach to 3D topographic data modelling Type de document : Article/Communication Auteurs : F. Penninga, Auteur ; Peter J. M. Van Oosterom, Auteur Année de publication : 2008 Article en page(s) : pp 751 - 779 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] base de données topographiques
[Termes IGN] données localisées 3D
[Termes IGN] modèle conceptuel de données localisées
[Termes IGN] reconstruction 3D du bâti
[Termes IGN] SIG 3D
[Termes IGN] simplification de contour
[Termes IGN] système de gestion de base de données
[Termes IGN] tétraèdreRésumé : (Auteur) This paper introduces a new compact topological 3D data structure. The proposed method models the real world as a complete decomposition of space and this subdivision is represented by a constrained tetrahedral network (TEN). Operators and definitions from the mathematical field of simplicial homology are used to define and handle this TEN structure. Only tetrahedrons need to be stored explicitly in a (single column) database table, while all simplexes of lower dimensions, constraints and topological relationships can be derived in views. As a result the data structure is relatively compact and easy to update, while it still offers favourable characteristics from a computational point of view as well as presence of topological relationships. Copyright Taylor & Francis Numéro de notice : A2008-231 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article DOI : 10.1080/13658810701673535 En ligne : https://doi.org/10.1080/13658810701673535 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29226
in International journal of geographical information science IJGIS > vol 22 n° 6-7 (june 2008) . - pp 751 - 779[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-08041 RAB Revue Centre de documentation En réserve L003 Disponible 079-08042 RAB Revue Centre de documentation En réserve L003 Disponible Unfolding the Earth: myriahedral projections / J. Van Wijk in Cartographic journal (the), vol 45 n° 1 (February 2008)
[article]
Titre : Unfolding the Earth: myriahedral projections Type de document : Article/Communication Auteurs : J. Van Wijk, Auteur Année de publication : 2008 Article en page(s) : pp 32 - 42 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Projections
[Termes IGN] carroyage géographique
[Termes IGN] planisphère
[Termes IGN] polyèdre
[Termes IGN] projection équivalenteRésumé : (Auteur) Myriahedral projections are a new class of methods for mapping the earth. The globe is projected on a myriahedron, a polyhedron with a very large number of faces. Next, this polyhedron is cut open and unfolded. The resulting maps have a large number of interrupts, but are (almost) conformal and conserve areas. A general approach is presented to decide where to cut the globe, followed by three different types of solution. These follow from the use of meshes based on the standard graticule, the use of recursively subdivided polyhedra and meshes derived from the geography of the earth. A number of examples are presented, including maps for tutorial purposes, optimal foldouts of Platonic solids, and a map of the coastline of the earth. Copyright British Cartographic Society Numéro de notice : A2008-132 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1179/000870408X276594 En ligne : https://doi.org/10.1179/000870408X276594 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29127
in Cartographic journal (the) > vol 45 n° 1 (February 2008) . - pp 32 - 42[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 030-08011 RAB Revue Centre de documentation En réserve L003 Disponible
Titre : 3D topography : a simplicial complex-based solution in a spatial DBMS Type de document : Thèse/HDR Auteurs : F. Penninga, Auteur Editeur : Delft : Netherlands Geodetic Commission NGC Année de publication : 2008 Collection : Netherlands Geodetic Commission Publications on Geodesy, ISSN 0165-1706 num. 66 Importance : 192 p. Format : 17 x 24 cm ISBN/ISSN/EAN : 978-90-6132-304-4 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géomatique
[Termes IGN] algorithme du simplexe
[Termes IGN] base de données localisées 3D
[Termes IGN] données localisées 3D
[Termes IGN] milieu urbain
[Termes IGN] modèle conceptuel de données localisées
[Termes IGN] objet géographique 3D
[Termes IGN] système de gestion de base de données
[Termes IGN] tétraèdre
[Termes IGN] Triangulated Irregular Network
[Termes IGN] visualisation 3DIndex. décimale : 32.00 Topographie - généralités Résumé : (Auteur) Current topographic products are limited to a real world representation in only two dimensions, with at best some additional point heights and contour lines. Modelling the real world in two dimensions implies a rather drastic simplification of three di-mensional real world elements. By representing these elements in two dimensions, loss of information is inevitable. Due to this simplification, accuracy of analysis results is limited and a meaningful, insightful representation of complex situations is hard to obtain. Environmental issues like high concentrations of particulate matter along highways in urban areas, the effects of noise and odour propagation and risk analysis of liquefied petroleum gas storage tanks are random examples of current issues in 3D urban planning in which more precision is required than 2D analyses can offer. In a time with increasing attention for these kind of environmental and sustainability issues, limitations of 2D models become real problematic and trigger the demand for 3D topography.
The development of 3D topography is also supply-driven, especially by the increasing availability of high density laser scan data. Height data becomes available with point densities -multiple height points per square meter- that were previously unthinkable with traditional photogrammetric stereo techniques. Direct 3D data ac-quisition by terrestrial laser scanning is emerging, thus providing detailed measure-ments of facades, tunnels and even indoor topography. The fast developments in this field are partly triggered by the emerging popularity of personal navigation devices, which will use 3D models in the future to simplify user interpretation of the (map) display.
Objective and research question
The objective of this research is to develop a data structure that is capable of han-dling large data volumes and offers support for loading, updating, querying, analysis and especially validation. To achieve this, a triangular approach will be used, due to its advantages in maintaining consistency, its robustness and editability. This tri-angular approach creates a network of triangles (in 2D) or tetrahedrons (in 3D), in which topographic features are represented by sets of triangles or tetrahedrons. Such a network is an example of an irregular tessellation, in which the real world is de--composed into smaller (triangle/tetrahedron-shaped) building blocks. The resulting networks are called TINs (Triangular Irregular Networks) or TENs (TEtrahedronised irregular Networks). The presence of boundaries of topographic features are ensured by the use of constraints, preventing the deletion of crucial boundary edges and trian-gles. Algorithms exist to calculate these constrained triangulations and constrained tetrahedronisations of topographic data.
In this research a two-step approach will be adopted. First one has to decide how real-world objects should be modelled into features, secondly one needs to store these features in such a way that the requirements in terms of querying, analysis and validation are met. An obvious step in dealing with large volumes of geographically referenced data, is to use a spatial database.
This objective is expressed in the main research question:
How can a 3D topographic representation be realised in a feature-based triangular data model?
Note that the term 'triangular' is used here in general dimension, so both triangle-and tetrahedron-based models will be considered. As mentioned before, a two-step approach will be adopted to achieve a solution to the main research question. In accordance with the two steps, two key questions can be distinguished:
How to develop a conceptual model that describes the real world phenomena (the topographic features), regarding the general purpose-characteristic of to-pographic data sets?
How to implement this conceptual model, i.e. how to develop a suitable DBMS data structure?
The results of this research will be summarised according to this two-step approach.
A conceptual data model for 3D topography
One of the basic assumptions within this research is the use of triangular data models. As a result, topographic features will be described as sets of triangles and these fea-tures will be connected by triangles as well, thus creating one triangular network. This research explored two different approaches to triangular modelling of 3D topography.
The first one is a very pragmatic hybrid approach that combines a 2.5D* sur-face with 3D objects for those cases where 2.5D modelling is not sufficient. In terms of triangular data structures, this approach combines a TIN with several TENs. These irregular data structures not only allow varying point density (de-pending on local model complexity), but extend this irregularity into varying even model dimensionality, thus offering the ultimate fit-for-purpose approach. Unfortunately, connecting TIN and TEN networks appeared to be very difficult at design level and during prototype implementation.
The second approach avoids these problems, since it is a full 3D approach using only a TEN. Two fundamental observations are of great importance:
Physical objects have by definition a volume. In reality, there are no point, line or polygon objects; only point, line or polygon representations exist (at a certain level of abstraction/generalisation).
The real world can be considered a volume partition: a set of nonoverlap-ping volumes that form a closed (i.e. no gaps within the domain) modelled space. Objects like 'earth' or 'air' are thus explicitly included in the model.
In topographic data models, planar features like walls or roofs are obviously very useful. They can be part of the volumetric data model as 'derived features', i.e. these features depend on the relationship between volume features. For example, the earth surface is the boundary between air and earth features, while a wall or a roof are the result of adjacent building and air features. In terms of UML, these planar features are modelled as association classes. As a result, planar features are lifetime dependent from the association between two volume features.
Among the advantages of the full volumetric approach are its explicit inclusion of air and earth (often subject of analysis), its extensibility (geology, air traf-fic/telecommunication corridors, etc.) and its strong mathematical definition (full connectivity enables the use of topology for query, analysis and validation). As a re-sult, topographic features will be modelled in a TEN. Each feature will be represented by a set of tetrahedrons.
A data structure for 3D topography
The newly developed data structure has three important characteristics:
It has a solid mathematical foundation. Operators and definitions from the mathematical field of Poincare simplicial homology (part of algebraic topology) are used to handle simplexes^, the basic elements in a triangular data structure. Simplexes are well defined, ordered and constructed of simplexes of lower di-mension. The boundary operator can be used to derive these less dimensional
*See section 2.2 for an overview of often-used dimension indicators
tA simplex can loosely be defined as the simplest shape in a dimension, in which simplest refers to minimising the number of points required to define such a shape, for instance a point, a line, a triangle and a tetrahedron. See section 4.1 for a proper mathematical definition simplexes. Based on the ordering of simplexes, one can determine orientation, a useful concept in GIS. Another important concept from simplicial homology is the simplicial complex, since such a set of connected simplexes will be used to model 3D topographic features.
It is developed as a spatial database data structure. Applying definitions and operators from simplicial homology enables one to store a TEN in a relatively compact way. The new simplicial complex-based method requires only explicit storage of tetrahedrons, while simplexes of lower dimensions (triangles, edges, nodes), constraints (which guarantee feature boundary presence) and topologi-cal relationships can be derived in views. Using functions to derive views from a table is typical database functionality. In this implementation, simplexes are en-coded by their vertices, similar to the annotation in simplicial homology. These simplex encodings are extended with a feature identifier, indicating which to-pographic feature is (partly) represented by this simplex. So, a tetrahedron is encoded as 83 =< vq, Vi, V2,v^, fid >. Two variants in simplex encoding have been developed: coordinate concatenation and identifier concatenation. The concept of coordinate concatenation is to concatenate x, y and z coordinates as node identifiers and to concatenate the resulting unique node codes to describe simplexes of higher dimension. The alternative approach, identifier concatena-tion, uses separate (meaningless) node identifiers to encode simplexes to reduce the number of coordinate repetitions, since a specific node will be part of multi-ple tetrahedrons. This approach requires an additional node table to store node geometries.
It is an editable data structure, which is a crucial prerequisite to be a feasible approach for topographic data storage. Incremental updates are required, since complete rebuilds of the TEN structure will be time-consuming due to the ex-pected data volumes. Whereas most existing update algorithms for constrained tetrahedronisations use node insertions, followed by edge reconstruction, this research presents edge insertion operators. Nine exhaustive and mutually exclusive cases are distinguished, based on the location in the TEN of the inserted edge's nodes. These operators guarantee the constrained edge's presence in the structure. Existing operators might fail to recover these edges, due to the pres-ence of nearby constrained edges, which would typically happen in topographic data sets.
Conclusions
This dissertation presents a new topological approach to data modelling, based on a tetrahedral network. Operators and definitions from the field of simplicial homology are used to define and handle this structure of tetrahedrons. Simplicial homology provides a solid mathematical foundation for the data structure and offers full control over orientation of simplexes and enables one to derive substantial parts of the TEN structure efficiently, instead of explicitly storing all primitives. DBMS characteristics as the usage of views, functions and function-based indexes are extensively used to realise this potential data reduction. A proof-of-concept implementation was created and tests with several data sets show that the prevailing view that tetrahedrons are more expensive in terms of storage when compared to polyhedrons, is not correct when using the proposed approach. Storage requirements for 3D objects in tetrahe-dronised form (excluding the space in between these objects) and 3D objects stored as polyhedrons, are in the same order of magnitude.
A TEN has favourable characteristics from a computational point of view. All elements of the tetrahedral network consist by definition of flat faces, all elements are convex and they are well defined. Validation of 3D objects is also simplified by tetrahedronisation. Furthermore, a full volumetric approach enables future integra-tion of topography with other 3D data like geological layers, polluted regions or air traffic and telecommunication corridors. The price of this full volumetric approach in terms of storage space is high (about 75% of the tetrahedrons models air or earth); nevertheless this approach is likely to become justifiable due to current developments towards sustainable urban development and increased focus on environmental issues.
Now the innovative aspects of the proposed method has to be identified. Neither the idea to use a TEN data structure for 3D data nor the idea to use simplexes (in terms of simplicial homology) in a DBMS implementation is new. However, the proposed approach reduces data storage and eliminates the need for explicit updates of both topology and simplexes of lower dimension. By doing so, the approach tackles common drawbacks as TEN extensiveness and laboriousness of maintaining topology. Furthermore, applying simplicial homology offers full control over orientation of sim-plexes, which is a significant advantage, especially in 3D. In addition to this aspect, the mathematical theory of simplicial homology offers a solid theoretical foundation for both the data structure and data operations. Integrating these concepts with database functionality results in a new innovative approach to 3D data modelling.
An often raised objection to a TEN approach is its presumed complexity. Obviously, a l:n relation exists between features and their tetrahedron representations. However, as long as a user handles only features (as polyhedrons) and implemented algorithms translate these polyhedrons into operations on the TEN, one can over-come the perceived complexity. Furthermore, the prevailing view that tetrahedrons are more expensive in terms of storage than polyhedrons has been falsified in this research.
Overall, the simplicial complex-based modelling approach provides a provable correct modelling method. The use of tetrahedrons is justified by the mathematical benefits and the acceptable storage requirements. Obviously, including air and earth within the model comes at a price, but -as stated earlier- this approach is likely to become justifiable, due to current sustainability and environmentally-driven developments. The decision to develop the data structure as a database structure contributes to the overall feasibility, since a database will become indispensable due to the expected data volumes.Note de contenu : Acknowledgements
1 Introduction
1.1 Motivation
1.2 Objective and main research question
1.3 Research scope and limitations
1.4 Contribution of the work
1.5 Outline
2 Research background
2.1 Problem domain: Towards 3D topography
2.2 Defining dimensions in the range 2D-3D
2.3 Deriving requirements for the conceptual data model and structure from the problem
2.4 Managing 3D data: related research on 3D data structures
2.5 Triangular data structures and algorithms
2.6 Relevant database concepts
I Conceptual modelling of 3D Topography
3 Two triangular data models for 3D topography
3.1 Approach 1: an integrated 2.5D/3D model
3.2 Approach 2: a full 3D data model
3.3 The choice for the full 3D approach
II A Data structure for 3D Topography
4 Theoretical foundations: Poincare simplicial homology
4.1 Mathematical description of simplexes
4.2 Orientation of simplexes
4.3 Combining simplexes: simplicial complexes
4.4 Operations on simplexes and simplicial complexes
5 A simplicial complex-based solution for 3D topography
5.1 Representing topographic features in a TEN
5.2 Early ideas: three TEN-based data structures for the full 3D approach
5.3 Preferred solution: applying simplicial homology to the TEN
5.4 Implementing the data structure in a DBMS environment
5.5 Summary
6 Updating features in the Data Structure
6.1 Incremental update: feature insertion
6.2 Incremental update: feature deletion
6.3 Quality improvement of TEN structure
6.4 Initial bulk loading and bulk rebuild
III Evaluation and conclusions
7 Evaluation and discussion
7.1 Evaluation material: three different data sets
7.2 Evaluating bulk tetrahedronisation process
7.3 Evaluating storage requirements
7.4 Evaluating initial visualisation tools
7.5 Discussing requirements for 3D data sets with correct topology
7.6 Identifying future developments
8 Conclusions
8.1 Results.
8.2 Main conclusions
8.3 Discussion
8.4 Future researchNuméro de notice : 15361 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Thèse étrangère DOI : sans En ligne : https://www.ncgeo.nl/index.php/en/publicatiesgb/publications-on-geodesy/item/250 [...] Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=62703 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 15361-01 32.00 Livre Centre de documentation Topographie Disponible 15361-02 32.00 Livre Centre de documentation Topographie Disponible
Titre : Analyses et requêtes de données géographiques 3D : contributions de la cristallographie géométrique Type de document : Thèse/HDR Auteurs : Benoit Poupeau , Auteur ; Anne Ruas , Directeur de thèse ; Olivier Bonin , Encadrant ; Benoit Deffontaines , Encadrant Editeur : Champs/Marne : Université de Marne-la-Vallée Année de publication : 2008 Importance : 223 p. Format : 21 x 30 cm Note générale : Bibliographie
Thèse pour obtenir le grade de docteur de l'université Paris-Est Marne-la-Vallée en sciences de l'information géographiqueLangues : Français (fre) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] analyse spatiale
[Termes IGN] bati
[Termes IGN] données localisées 3D
[Termes IGN] effondrement de terrain
[Termes IGN] espace topologique
[Termes IGN] graphe
[Termes IGN] polyèdre
[Termes IGN] primitive géométrique
[Termes IGN] primitive volumique
[Termes IGN] requête spatiale
[Termes IGN] théorie des graphesIndex. décimale : THESE Thèses et HDR Résumé : (Auteur) Un des rôles des SIG 3D est d'intégrer et de mettre en cohérence des données issues de producteurs de données variés tout en respectant les choix faits en fonction des besoins des utilisateurs, en termes de géométrie et de topologie. Les SIG 3D actuels utilisent généralement une modélisation géométrique et topologique unique qui facilite, entre autres, les requêtes comme celles calculées à partir des modèles topologiques tels que le parcours de proche en proche des primitives géométriques d'un objet ou de ses voisins. En contrepartie, cette homogénéisation entraîne une perte des spécificités des modèles, de lourds calculs de conversion et ne corrige pas, sans une aide extérieure, les problèmes inhérents à l'acquisition et à la modélisation. Cette thèse propose un modèle d'analyse pour les SIG 3D permettant d'opérer des requêtes sur un objet (analyse intra-objet), quel que soit le choix technique de l'utilisateur, ou sur un ensemble d'objets (analyse inter-objets), même s'ils ne sont pas parfaitement cohérents. A partir de principes issus de la cristallographie, ce modèle, nommé Cristage, analyse les symétries de chaque objet pour décrire sa structure, c'est-à-dire la manière dont les primitives sont agencées entre elles. Complémentaire des modèles topologiques, cette première abstraction donne une vision globale de l'objet, ce qui facilite certaines requêtes comme l'extraction du toit d'une cavité ou la simplification géométrique d'un bâtiment 3D. L'analyse des différents éléments de symétrie (plans, axes et centre) offre une seconde abstraction : la maille. Considérée en cristallographie comme l'enveloppe du plus petit parallélépipède conservant les propriétés géométriques, elle est utilisée comme une boîte englobante adaptée à la forme de l'objet. Elle permet, en particulier, la mise en relation logique des objets géographiques, quelle que soit leur dimension. A l'aide des mailles, deux graphes sont calculés. Le premier, qualifié de graphe d'incidence, décrit les relations entre objets et facilite le parcours entre eux. Le second, appelé graphe temporel, dessine, pour un objet, l'évolution de ses relations avec son environnement. Ce modèle, développé dans le prototype éponyme, a été utilisé dans diverses applications dont la simplification de bâtiments 3D et dans un contexte d'affaissement minier. Note de contenu : Introduction Générale
- Contexte
- Problématique
- Approche retenue
- Organisation du mémoire
CH 1 ETAT DE L'ART EN MODELISATION 3D DES OBJETS ET PROPOSITION D'UN MODELE ADAPTE A L'ANALYSE
1.1 Introduction : de la visualisation à l'analyse
1.2 La modélisation géométrique
1.2.1 Introduction : aperçu des classifications
1.2.2 Les modèles constructifs
1.2.3 Les modèles par énumération spatiale
1.2.4 Les modèles par frontière
1.2.5 Conclusion sur les modèles géométriques
1.3 La modélisation topologique
1.3.1 Notions de topologie
1.3.2 Les modèles topologiques 2D
1.3.3 Les modèles topologiques dans Rn
1.3.4 Conclusion sur les modèles topologiques
1.4 L'approche « géométrico-topologique » du modèle Cristage : une première proposition
1.5 Conclusion : vers une analyse des principaux éléments constitutifs des objets géographiques
CH 2 ANALYSE MORPHOLOGIQUE DES OBJETS GEOGRAPHIQUES
2.1 Introduction : l'analyse de la forme, un complément au modèle géométricotopologique de Cristage
2.2 Notions de cristallographie
2.2.1 Introduction : de Stenon à Miller, un bref aperçu de l'histoire de la cristallographie géométrique
2.2.2 Motif
2.2.3 Réseau
2.2.4 Maille
2.2.5 Structure
2.2.6 Conclusion : la cristallographie, outil de description adapté aux objets géographiques ?
2.3 Apports de la cristallographie pour une description haut niveau des objets géographiques
2.3.1 Introduction : intégration des concepts issus de la cristallographie
2.3.2 La projection stéréographique
2.3.3 La symétrie comme outil d'analyse
2.3.4 Structure de l'objet géographique
2.3.5 Maille de l'objet géographique
2.3.6 Conclusion : la cristallographie, clé de voûte de notre abstraction de l'information géographique en vue de son analyse
2.4 Deux applications de la structure et la maille : la subdivision géométrique et la simplification de bâtiments 3D
2.4.1 Introduction : la structure et la maille, outils d'analyse
2.4.2 La subdivision en convexes
2.4.3 La simplification de bâtiments
2.4.4 Conclusion : la maille ou l'élément fondamental pour une analyse intra-objet.
2.5 Conclusion générale : la cristallographie et l'abstraction de l'information géographique
CH 3 MISE EN RELATIONS DES OBJETS GEOGRAPHIQUES
3.1 Introduction : la modélisation d'un phénomène ou les besoins d'une analyse spatio-temporelle
3.2 Mise en relation des objets géographiques
3.2.1 Introduction : vers une abstraction généralisée des objets géographiques
3.2.2 Rappels sur les espaces proximaux
3.2.3 Principes de mise en relation
3.2.4 Description des relations entre objets géographiques
3.2.5 Conclusion : de la description à l'évolution des relations
3.3 Évolution des relations dans le temps
3.3.1 Introduction : l'intégration du temps ou l'évolution temporelle
3.3.2 Rappels en théorie des graphes
3.3.3 Le graphe d'adjacence
3.3.4 Le graphe temporel
3.3.5 Conclusion : vers une gestion particulière des interfaces
3.4 Conclusion générale : utilisation des mailles et des graphes dans un contexte d'affaissement minier
Conclusions et perspectives générales
- Réflexions sur une modélisation 3D unique pour un SIG
- Propositions sur la structureNuméro de notice : 13660 Affiliation des auteurs : COGIT (1988-2011) Thématique : GEOMATIQUE Nature : Thèse française Note de thèse : Thèse de doctorat : Sciences de l'information géographique : Paris-Est Marne-la-Vallée : 2008 Organisme de stage : COGIT (IGN) nature-HAL : Thèse DOI : sans En ligne : http://www.theses.fr/2008PEST0254 Format de la ressource électronique : URL accès réservé Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=45230 Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 13660-01 K325 Livre LASTIG Dépôt en unité Exclu du prêt PermalinkLe sauvetage des églises de Voskopoja (Albanie) : la documentation métrique des fresques pour leur sauvegarde et leur restauration / Thomas Leroy in XYZ, n° 109 (décembre 2006 - février 2007)PermalinkReprésentation du champ de pesanteur sur des repères d'ondelettes sphériques / Isabelle Panet in Bulletin d'information scientifique et technique de l'IGN, n° 75 (mars 2006)PermalinkTechnological aspects of a full 3D cadastral registration / Jantien E. Stoter in International journal of geographical information science IJGIS, vol 19 n° 6 (july 2005)PermalinkK-guarding of polyhedral terrain / B. Kaucic in International journal of geographical information science IJGIS, vol 18 n° 7 (november 2004)PermalinkContribution à la reconstruction du bâti en milieu urbain, à l'aide d'images aériennes stéréoscopiques à grande échelle : étude d'une approche structurelle / Franck Taillandier (2004)PermalinkDétermination d'une surface polyédrique continue optimale à partir d'un fouillis de plans / Hassan Jibrini (2004)PermalinkA linear algorithm for computing the spherical harmonic coefficients of the gravitational potential from a constant density polyhedron / Olivier Jamet (2004)PermalinkSemiautomated building extraction based on CSG model-image fitting / Yi-Hsing Tseng in Photogrammetric Engineering & Remote Sensing, PERS, vol 69 n° 2 (February /2003)PermalinkDéveloppement en harmoniques sphériques de la contribution au potentiel de gravité d'un volume polyédrique représenté par sa surface externe / E. Thomas (2003)Permalink