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A model-based approach for reconstructing a terrain surface from airborne Lidar data / Gunho Sohn in Photogrammetric record, vol 23 n° 122 (June - August 2008)
[article]
Titre : A model-based approach for reconstructing a terrain surface from airborne Lidar data Type de document : Article/Communication Auteurs : Gunho Sohn, Auteur ; Ian J. Dowman, Auteur Année de publication : 2008 Article en page(s) : pp 170 - 193 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] données lidar
[Termes IGN] filtrage de points
[Termes IGN] modèle numérique de surface
[Termes IGN] optimisation (mathématiques)
[Termes IGN] pente
[Termes IGN] semis de pointsRésumé : (Auteur) A lidar filtering technique is used to differentiate on-terrain points and off-terrain points from a cloud of 3D point data collected by a lidar system. A major issue of concern in this low-level filter is to design a methodology to ensure a continual adaptation to variations of terrain slopes and object scales. In this paper, a new lidar filtering technique which hierarchically fragments lidar data into piecewise planar terrain models is introduced. Once a number of hypothetical planar terrain models are generated to fit the terrain surface of the underlying area, the optimal terrain model to produce the minimum labelling errors is determined based on minimum description length (MDL) principles. This hypothesis-verification optimisation is achieved in a coarse-to-fine strategy by which the entire terrain surface is incrementally reconstructed by increasing the number of planar terrain models fitted. The proposed technique was successfully applied to a digital surface model provided within an OEEPE lidar trial, showing 0·94% of Type I errors and 6·75% of Type II errors compared to manually classified reference data. Copyright RS&PS + Blackwell Publishing Numéro de notice : A2008-296 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1111/j.1477-9730.2008.00483.x En ligne : https://doi.org/10.1111/j.1477-9730.2008.00483.x Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29289
in Photogrammetric record > vol 23 n° 122 (June - August 2008) . - pp 170 - 193[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 106-08021 RAB Revue Centre de documentation En réserve L003 Disponible Spatial optimization as a generative technique for sustainable multiobjective land-use allocation / A. Ligmann-Zielinska in International journal of geographical information science IJGIS, vol 22 n° 6-7 (june 2008)
[article]
Titre : Spatial optimization as a generative technique for sustainable multiobjective land-use allocation Type de document : Article/Communication Auteurs : A. Ligmann-Zielinska, Auteur ; R.L. Church, Auteur ; Piotr Jankowski, Auteur Année de publication : 2008 Article en page(s) : pp 601 - 622 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications SIG
[Termes IGN] allocation
[Termes IGN] aménagement du territoire
[Termes IGN] développement durable
[Termes IGN] modèle mathématique
[Termes IGN] optimisation (mathématiques)
[Termes IGN] répartition géographique
[Termes IGN] système d'information géographique
[Termes IGN] utilisation du sol
[Termes IGN] Washington (Etats-Unis ; état)Résumé : (Auteur) In this paper, we examine the applicability of spatial optimization as a generative modelling technique for sustainable land-use allocation. Specifically, we test whether spatial optimization can be used to generate a number of compromise spatial alternatives that are both feasible and different from each other. We present a new spatial multiobjective optimization model, which encourages efficient utilization of urban space through infill development, compatibility of adjacent land uses, and defensible redevelopment. The model uses a density-based design constraint developed by the authors. The constraint imposes a predefined level of consistent neighbourhood development to promote contiguity and compactness of urban areas. First, the model is tested on a hypothetical example. Further, we demonstrate a real-world application of the model to land-use planning in Chelan, a small environmental amenity town in the north-central region of the State of Washington, USA. The results indicate that spatial optimization is a promising method for generating land-use alternatives for further consideration in spatial decision-making. Copyright Taylor & Francis Numéro de notice : A2008-223 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/13658810701587495 En ligne : https://doi.org/10.1080/13658810701587495 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29218
in International journal of geographical information science IJGIS > vol 22 n° 6-7 (june 2008) . - pp 601 - 622[article]Exemplaires(2)
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 Image-based 3D surface reconstruction by combination of photometric, geometric, and real-aperture methods / Pablo d' Angelo in ISPRS Journal of photogrammetry and remote sensing, vol 63 n° 3 (May - June 2008)
[article]
Titre : Image-based 3D surface reconstruction by combination of photometric, geometric, and real-aperture methods Type de document : Article/Communication Auteurs : Pablo d' Angelo, Auteur ; C. Wöhler, Auteur Année de publication : 2008 Article en page(s) : pp 297 - 321 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Photogrammétrie numérique
[Termes IGN] données de terrain
[Termes IGN] gradient de pente
[Termes IGN] pente
[Termes IGN] photométrie
[Termes IGN] polarisation
[Termes IGN] profondeur
[Termes IGN] programmation non linéaire
[Termes IGN] reconstruction 3D
[Termes IGN] réflectanceRésumé : (Auteur) An image-based 3D surface reconstruction method based on simultaneous evaluation of intensity and polarisation features (shape from photopolarimetric reflectance) and its combination with absolute depth data is introduced in this article. The proposed technique is based on the analysis of single or multiple intensity and polarisation images. To compute the surface gradients, we present a global optimisation method based on a variational framework and a local optimisation method based on solving a set of non-linear equations individually for each image pixel. These approaches are suitable for strongly non-Lambertian surfaces and those of diffuse reflectance behaviour and can also be adapted to surfaces of non-uniform albedo. We describe how independently measured absolute depth data is integrated into the shape from photopolarimetric reflectance framework in order to increase the accuracy of the 3D reconstruction result. In this context we concentrate on dense but noisy depth data obtained by depth from defocus and on sparse but accurate depth data obtained by stereo or structure from motion analysis. We show that depth from defocus information should preferentially be used for initialising the optimisation schemes for the surface gradients. For integration of sparse depth information, we suggest an optimisation scheme that simultaneously adapts the surface gradients to the measured intensity and polarisation data and to the surface slopes implied by depth differences between pairs of depth points. In principle, arbitrary sources of depth information are possible in the presented framework. Experiments on synthetic and on real-world data reveal that while depth from defocus is especially helpful for providing an initial estimate of the surface gradients and the albedo in the absence of a-priori knowledge, integration of stereo or structure from motion information significantly increases the 3D reconstruction accuracy. In our real-world experiments, we regard the scenarios of 3D reconstruction of raw forged iron surfaces in the domain of industrial quality inspection and the generation of a digital elevation model of a section of the lunar surface in the context of space-based planetary exploration. Copyright ISPRS Numéro de notice : A2008-213 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2007.09.005 En ligne : https://doi.org/10.1016/j.isprsjprs.2007.09.005 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29208
in ISPRS Journal of photogrammetry and remote sensing > vol 63 n° 3 (May - June 2008) . - pp 297 - 321[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 081-08031 SL Revue Centre de documentation Revues en salle Disponible Seeking the Pareto front for multiobjective spatial optimization problems / B. Huang in International journal of geographical information science IJGIS, vol 22 n° 4-5 (april 2008)
[article]
Titre : Seeking the Pareto front for multiobjective spatial optimization problems Type de document : Article/Communication Auteurs : B. Huang, Auteur ; P. Fery, Auteur ; L. Xue, Auteur ; Y. Wang, Auteur Année de publication : 2008 Article en page(s) : pp 507 - 526 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications SIG
[Termes IGN] approximation
[Termes IGN] erreur systématique
[Termes IGN] optimisation (mathématiques)
[Termes IGN] réseau routier
[Termes IGN] Singapour
[Termes IGN] système d'information géographiqueRésumé : (Auteur) Spatial optimization problems, such as route selection, usually involve multiple, conflicting objectives relevant to locations. An ideal approach to solving such multiobjective optimization problems (MOPs) is to find an evenly distributed set of Pareto-optimal alternatives, which is capable of representing the possible trade-off among different objectives. However, these MOPs are commonly solved by combining the multiple objectives into a parametric scalar objective, in the form of a weighted sum function. It has been found that this method fails to produce a set of well spread solutions by disregarding the concave part of the Pareto front. In order to overcome this ill-behaved nature, a novel adaptive approach has been proposed in this paper. This approach seeks to provide an unbiased approximation of the Pareto front by tuning the search direction in the objective space according to the largest unexplored region until a set of well-distributed solutions is reached. To validate the proposed methodology, a case study on multiobjective routing has been performed using the Singapore road network with the support of GIS. The experimental results confirm the effectiveness of the approach. Copyright Taylor & Francis Numéro de notice : A2008-152 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/13658810701492365 En ligne : https://doi.org/10.1080/13658810701492365 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29147
in International journal of geographical information science IJGIS > vol 22 n° 4-5 (april 2008) . - pp 507 - 526[article]Exemplaires(2)
Code-barres Cote Support Localisation Section Disponibilité 079-08031 RAB Revue Centre de documentation En réserve L003 Disponible 079-08032 RAB Revue Centre de documentation En réserve L003 Disponible Sensitivity analysis of spatially aggregated responses: a gradient-based method / F. Pantus in International journal of geographical information science IJGIS, vol 22 n° 4-5 (april 2008)
[article]
Titre : Sensitivity analysis of spatially aggregated responses: a gradient-based method Type de document : Article/Communication Auteurs : F. Pantus, Auteur ; N. Ellis, Auteur ; H. Possingham, Auteur ; et al., Auteur Année de publication : 2008 Article en page(s) : pp 575 - 599 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] agrégation spatiale
[Termes IGN] algorithme du gradient
[Termes IGN] analyse de sensibilité
[Termes IGN] données socio-économiques
[Termes IGN] espace vectoriel
[Termes IGN] noeud
[Termes IGN] polygoneRésumé : (Auteur) We often need to report on environmental, economic and social indicators, and properties at aggregated spatial scales, e.g. average income per suburb. To do this, we invariably create reporting polygons that are somewhat arbitrary. The question arises: how much does this arbitrary subdivision of space affect the outcome? In this paper, we develop a new, gradient-based framework for carrying out a rigorous analysis of the sensitivity of integrating functions to quantitative changes in their spatial configuration. This approach is applied to both analytical and empirical models, and it allows the reporting of a hierarchy of sensitivity measures (from global to local). We found that the concepts of a vector space representing the spatial configurations and the response (hyper-)surface on which gradients indicate the sensitivities to be helpful in developing the sensitivity analytical framework of spatial configurations in different dimensions. This approach works well with both analytical and empirical integrating functions. This approach resulted in a clear ranking of the sensitivities of the responses to changes in the reporting regions in an existing environmental reporting application. The approach also allowed us to find which vertices, and the directions of change of those vertices, influenced the outcome most. The application of the spatial framework allows the results to be reported in a hierarchical way, from the sensitivities of an integrative response to changes in a whole reserve/reporting system, down to the sensitivity along each of the dimensions of the vertices in the spatial configuration. The results of the spatial sensitivity framework that we developed in this paper can be readily visualized by plotting the sensitivities as vectors on geographic maps. This simplifies the presentation and facilitates the uptake of the results in the situations where the spatial configurations are complicated. Numéro de notice : A2008-155 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/13658810701587784 En ligne : https://doi.org/10.1080/13658810701587784 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29150
in International journal of geographical information science IJGIS > vol 22 n° 4-5 (april 2008) . - pp 575 - 599[article]Exemplaires(2)
Code-barres Cote Support Localisation Section Disponibilité 079-08031 RAB Revue Centre de documentation En réserve L003 Disponible 079-08032 RAB Revue Centre de documentation En réserve L003 Disponible Optimisation de la mise à jour des bases de données géospatiales : proposition d'une procédure automatisée d'appariement géométrique d'objets linéaires / M. Bouziani in Revue internationale de géomatique, vol 18 n° 1 (mars – mai 2008)PermalinkPhase unwrapping for SAR interferometry based on an ant colony optimization algorithm / Z.Q. Wei in International Journal of Remote Sensing IJRS, vol 29 n°3-4 (February 2008)PermalinkPermalinkCSTST 2008, the 5th International conference on soft computing as transdisciplinary science and technology, October 28th - October 31st 2008, University of Cergy-Pontoise, France / Richard Chbeir (2008)PermalinkÉtude comparative de différentes méthodes d'estimation / Samuel Nahmani (2008)PermalinkEtude et développement d'un outil de mise en correspondance / Marie Feisthauer (2008)PermalinkGénéralisation automatique / Julien Gaffuri (2008)PermalinkGNU octave manual, version 3 / J.W. Eaton (2008)PermalinkKalman filtering, theory and practice using MATLAB / Mohinder S. Grewal (2008)PermalinkA new computationally efficient stochastic approach for building reconstruction from satellite data / Florent Lafarge (2008)Permalink