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Geographies of maritime transport, Ch. 4. Geography versus topology in the evolution of the global container shipping network (1977-2016) / César Ducruet (2020)
Titre de série : Geographies of maritime transport, Ch. 4 Titre : Geography versus topology in the evolution of the global container shipping network (1977-2016) Type de document : Chapitre/Contribution Auteurs : César Ducruet, Auteur ; Justin Berli , Auteur ; Mattia Bunel , Auteur Editeur : Camberley [Royaume Uni] : Edward Elgar Publishing Année de publication : 2020 Projets : 1-Pas de projet / Importance : pp 49 - 70 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] données spatiotemporelles
[Termes IGN] navire
[Termes IGN] système d'information géographique
[Termes IGN] théorie des graphes
[Termes IGN] transport maritimeRésumé : (Auteur) The dynamical properties of so-called spatial and complex networks are often overlooked in graph theory and network science in general. Container shipping provides a rare example of a global transport network that went through tremendous technological and geographic changes in the last decades or so. This chapter proposes for the first time an empirical analysis of no less than 40 years of inter-port vessel movement data (1977-2016) to describe the evolving properties of the global container shipping network. Main results confirm a number of stylized facts such as the growing size, connectivity, and centralization of this network due to several factors such as economies of scale in liner shipping and the rationalization of related maritime services, the emergence of hub ports, etc. We also provide a new cartography of how had the global container shipping network been geographically distributed over time, thereby highlighting major shifts in terms of port hierarchies and main corridors. We believe that this chapter will contribute to a better understanding of the complex linkages between network structure, technological change, and spatial change, opening the way for new research paths on maritime transport research and network science in general when focusing on evolutionary dynamics. Numéro de notice : H2020-002 Affiliation des auteurs : LASTIG COGIT+Ext (2012-2019) Autre URL associée : vers HAL Thématique : GEOMATIQUE Nature : Chapître / contribution nature-HAL : ChOuvrScient DOI : 10.4337/9781788976640.00008 Date de publication en ligne : 16/04/2020 En ligne : https://doi.org/10.4337/9781788976640.00008 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95084 Documents numériques
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Geography vs. topology... - pdf auteurAdobe Acrobat PDF Image processing applications in object detection and graph matching: from Matlab development to GPU framework / Beibei Cui (2020)
Titre : Image processing applications in object detection and graph matching: from Matlab development to GPU framework Type de document : Thèse/HDR Auteurs : Beibei Cui, Auteur ; Jean-Charles Créput, Directeur de thèse Editeur : Dijon : Université Bourgogne Franche-Comté UBFC Année de publication : 2020 Importance : 137 p. Format : 21 x 30 cm Note générale : bibliographie
Thèse de Doctorat de l'Université Bourgogne Franche-Comté préparée à l'Université de Technologie de Belfort-Montbéliard, InformatiqueLangues : Français (fre) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] appariement de graphes
[Termes IGN] détection d'objet
[Termes IGN] entropie
[Termes IGN] extraction de traits caractéristiques
[Termes IGN] graphe planaire
[Termes IGN] Matlab
[Termes IGN] ondelette
[Termes IGN] processeur graphique
[Termes IGN] Ransac (algorithme)
[Termes IGN] reconnaissance de formesIndex. décimale : THESE Thèses et HDR Résumé : (auteur) Automatically finding correspondences between object features in images is of main interest for several applications, as object detection and tracking, flow velocity estimation, identification, registration, and many derived tasks. In this thesis, we address feature correspondence within the general framework of graph matching optimization and with the principal aim to contribute, at a final step, to the design of new and parallel algorithms and their implementation on GPU (Graphics Processing Unit) systems. Graph matching problems can have many declinations, depending on the assumptions of the application at hand. We observed a gap between applications based on local cost objective functions, and those applications with higher-order cost functions, that evaluate similarity between edges of the graphs, or hyperedges when considering hypergraphs. The former class provides convolution-based algorithms already having parallel GPU implementations. Whereas, the latter class puts the emphasis on geometric inter-feature relationships, transforming the correspondence problem to a purely geometric problem stated in a high dimensional space, generally modeled as an integer quadratic programming, for which we did not find GPU implementations available yet.Two complementary approaches were adopted in order to contribute to addressing higher-order geometric graph matching on GPU. Firstly, we study different declinations of feature correspondence problems by the use of the Matlab platform, in order to reuse and provide state-of-the-art solution methods, as well as experimental protocols and input data necessary for a GPU platform with evaluation and comparison tools against existing sequential algorithms, most of the time developed in Matlab framework. Then, the first part of this work concerns three contributions, respectively, to background and frame difference application, to feature extraction problem from images for local correspondences, and to the general graph matching problem, all based on the combination of methods derived from Matlab environment. Secondly, and based on the results of Matlab developments, we propose a new GPU framework written in CUDA C++ specifically dedicated to geometric graph matching but providing new parallel algorithms, with lower computational complexity, as the self-organizing map in the plane, derived parallel clustering algorithms, and distributed local search method. These parallel algorithms are then evaluated and compared to the state-of-the-art methods available for graph matching and following the same experimental protocol. This GPU platform constitutes our final and main proposal to contribute to bridging the gap between GPU development and higher-order graph matching. Note de contenu : 1- Introduction
2- Background
3- Background subtraction and frame difference for multi-object detection
4- Using Marr-wavelets and entropy/response to automatic feature detection
5- Affinity-preserving fixed point APRIP in Matlab framework for graph matching
6- Planar graph matching in GPU
7- Conclusion and future workNuméro de notice : 28328 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Thèse française Note de thèse : Thèse de Doctorat : Informatique : UBFC : 2020 Organisme de stage : CIAD Dijon DOI : sans En ligne : https://tel.archives-ouvertes.fr/tel-02902973/document Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98402
Titre : Multi-scale point cloud analysis Titre original : Analyse multi-échelle de nuage de points Type de document : Thèse/HDR Auteurs : Thibault Lejemble, Auteur ; Loïc Barthe, Directeur de thèse Editeur : Toulouse : Université de Toulouse 3 Paul Sabatier Année de publication : 2020 Importance : 142 p. Format : 21 x 30 cm Note générale : bibliographie
Thèse en vue du Doctorat de l'Université de Toulouse en Informatique et TélécommunicationsLangues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] analyse multiéchelle
[Termes IGN] analyse multirésolution
[Termes IGN] anisotropie
[Termes IGN] approche hiérarchique
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] extraction automatique
[Termes IGN] géométrie différentielle
[Termes IGN] graphe
[Termes IGN] reconnaissance de formes
[Termes IGN] segmentation en plan
[Termes IGN] segmentation en régions
[Termes IGN] semis de points
[Termes IGN] visualisation 3DIndex. décimale : THESE Thèses et HDR Résumé : (auteur) 3D acquisition techniques like photogrammetry and laser scanning are commonly used in numerous fields such as reverse engineering, archeology, robotics and urban planning. The main objective is to get virtual versions of real objects in order to visualize, analyze and process them easily. Acquisition techniques become more and more powerful and affordable which creates important needs to process efficiently the resulting various and massive3D data. Data are usually obtained in the form of unstructured 3D point cloud sampling the scanned surface. Traditional signal processing methods cannot be directly applied due to the lack of spatial parametrization. Points are only represented by their 3D coordinates without any particular order. This thesis focuses on the notion of scale of analysis defined by the size of the neighborhood used to locally characterize the point-sampled surface. The analysis at different scales enables to consider various shapes which increases the analysis pertinence and the robustness to acquired data imperfections. We first present some theoretical and practical results on curvature estimation adapted to a multi-scale and multi-resolution representation of point clouds. They are used to develop multi-scale algorithms for the recognition of planar and anisotropic shapes such as cylinder sand feature curves. Finally, we propose to compute a global 2D parametrization of the underlying surface directly from the 3D unstructured point cloud. Note de contenu : Introduction
1- Multi-scale differential analysis of point clouds
2- Plane detection using persistence analysis of graph
3- An isotropic features detection using curvature lines
4- Point cloud parametrization
ConclusionNuméro de notice : 28583 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Thèse française Note de thèse : Thèse de Doctorat : Informatique et Télécommunications : Toulouse 3 : 2020 Organisme de stage : Institut de recherche en informatique de Toulouse En ligne : https://tel.archives-ouvertes.fr/tel-03170824/document Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97923
Titre : Planar maps, random walks and circle packing : École d'été de probabilités de Saint-Flour XLVIII - 2018 Type de document : Guide/Manuel Auteurs : Asaf Nachmias, Éditeur scientifique Editeur : Berlin, Heidelberg, Vienne, New York, ... : Springer Année de publication : 2020 Collection : Lecture notes in Mathematics num. 2243 Importance : 120 p. ISBN/ISSN/EAN : 978-3-030-27968-4 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Statistiques
[Termes IGN] arbre aléatoire
[Termes IGN] fonction harmonique
[Termes IGN] graphe planaire
[Termes IGN] modèle de MarkovIndex. décimale : 23.60 Statistiques et probabilités Résumé : (Editeur) This open access book focuses on the interplay between random walks on planar maps and Koebe’s circle packing theorem. Further topics covered include electric networks, the He–Schramm theorem on infinite circle packings, uniform spanning trees of planar maps, local limits of finite planar maps and the almost sure recurrence of simple random walks on these limits. One of its main goals is to present a self-contained proof that the uniform infinite planar triangulation (UIPT) is almost surely recurrent. Full proofs of all statements are provided. A planar map is a graph that can be drawn in the plane without crossing edges, together with a specification of the cyclic ordering of the edges incident to each vertex. One widely applicable method of drawing planar graphs is given by Koebe’s circle packing theorem (1936). Various geometric properties of these drawings, such as existence of accumulation points and bounds on the radii, encode important probabilistic information, such as the recurrence/transience of simple random walks and connectivity of the uniform spanning forest. This deep connection is especially fruitful to the study of random planar maps. The book is aimed at researchers and graduate students in mathematics and is suitable for a single-semester course; only a basic knowledge of graduate level probability theory is assumed. Note de contenu : 1. Introduction
1.1 The Circle Packing Theorem
1.2 Probabilistic Applications
2. Random Walks and Electric Networks
2.1 Harmonic Functions and Voltages
2.2 Flows and Currents
2.3 The Effective Resistance of a Network
2.4 Energy
2.5 Infinite Graphs
2.6 Random Paths
2.7 Exercises
3. The CirclePacking Theorem
3.1 Planar Graphs, Maps and Embeddings
3.2 Proof of the Circle Packing Theorem
4. Parabolic and Hyperbolic Packings
4.1 Infinite Planar Maps
4.2 The Ring Lemma and Infinite Circle Packings
4.3 Statement of the He–Schramm Theorem
4.4 Proof of the He–Schramm Theorem
4.5 Exercises
5. Planar Local Graph Limits
5.1 Local Convergenceof Graphs and Maps
5.2 The Magic Lemma
5.3 Recurrence of Bounded Degree Planar Graph Limits
5.4 Exercises
6. Recurrence of Random Planar Maps
6.1 Star-Tree Transform
6.2 Stationary Random Graphs and Markings
6.3 Proof of Theorem
7. Uniform Spanning Trees of Planar Graphs
7.1 Introduction
7.2 Basic Properties of the UST
7.3 Limits over Exhaustions:The Free and Wired USF
7.4 Planar Duality
7.5 Connectivity of the Free Forest
7.6 Exercises
8. Related TopicsNuméro de notice : 26541 Affiliation des auteurs : non IGN Thématique : MATHEMATIQUE Nature : Manuel de cours DOI : 10.1007/978-3-030-27968-4 En ligne : http://doi.org/10.1007/978-3-030-27968-4 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97764 A space-time varying graph for modelling places and events in a network / Ikechukwu Maduako in International journal of geographical information science IJGIS, vol 33 n° 10 (October 2019)
[article]
Titre : A space-time varying graph for modelling places and events in a network Type de document : Article/Communication Auteurs : Ikechukwu Maduako, Auteur ; Monica Wachowicz, Auteur Année de publication : 2019 Article en page(s) : pp 1915 - 1935 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] accident de la route
[Termes IGN] analyse des risques
[Termes IGN] analyse spatio-temporelle
[Termes IGN] connexité (graphes)
[Termes IGN] graphe
[Termes IGN] relation topologique
[Termes IGN] représentation spatiale
[Termes IGN] réseau routier
[Termes IGN] système d'information géographique
[Termes IGN] voisinage (relation topologique)Résumé : (auteur) Modelling topological relationships between places and events is challenging especially because these relationships are dynamic, and their evolutionary analysis relies on the explanatory power of representing their interactions across different temporal resolutions. In this paper, we introduce the Space-Time Varying Graph (STVG) based on the whole graph approach that combines directed and bipartite subgraphs with a time-tree for representing the complex interaction between places and events across time. We demonstrate how the proposed STVG can be exploited to identify and extract evolutionary patterns of traffic accidents using graph metrics, ad-hoc graph queries and clustering algorithms. The results reveal evolutionary patterns that uncover the places with high incidence of accidents over different time resolutions, reveal the main reasons why the traffic accidents have occurred, and disclose evolving communities of densely connected traffic accidents over time. Numéro de notice : A2019-393 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/13658816.2019.1603386 Date de publication en ligne : 17/04/2019 En ligne : https://doi.org/10.1080/13658816.2019.1603386 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93497
in International journal of geographical information science IJGIS > vol 33 n° 10 (October 2019) . - pp 1915 - 1935[article]Analysis of collaboration networks in OpenStreetMap through weighted social multigraph mining / Quy Thy Truong in International journal of geographical information science IJGIS, vol 33 n° 7 - 8 (July - August 2019)PermalinkComputing and querying strict, approximate, and metrically refined topological relations in linked geographic data / Blake Regalia in Transactions in GIS, vol 23 n° 3 (June 2019)PermalinkDeeply integrating linked data with geographic information systems / Gengchen Mai in Transactions in GIS, vol 23 n° 3 (June 2019)PermalinkPiecewise-planar approximation of large 3D data as graph-structured optimization / Stéphane Guinard in ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences, vol IV-2/W5 (May 2019)PermalinkA graph-based approach for the structural analysis of road and building layouts / Mathieu Domingo in Geo-spatial Information Science, vol 22 n° 1 (March 2019)PermalinkImproving LiDAR classification accuracy by contextual label smoothing in post-processing / Nan Li in ISPRS Journal of photogrammetry and remote sensing, vol 148 (February 2019)PermalinkPoint clouds for direct pedestrian pathfinding in urban environments / Jesus Balado in ISPRS Journal of photogrammetry and remote sensing, vol 148 (February 2019)PermalinkPermalinkPermalinkSpatial data management in apache spark: the GeoSpark perspective and beyond / Jia Yu in Geoinformatica, vol 23 n° 1 (January 2019)Permalink