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Least visible path analysis in raster terrain / M. Lu in International journal of geographical information science IJGIS, vol 22 n° 6-7 (june 2008)
[article]
Titre : Least visible path analysis in raster terrain Type de document : Article/Communication Auteurs : M. Lu, Auteur ; J.F. Zhang, Auteur ; P. Fan, Auteur ; Zhengjie Fan, Auteur Année de publication : 2008 Article en page(s) : pp 645 - 656 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] analyse de données
[Termes IGN] C++
[Termes IGN] données matricielles
[Termes IGN] implémentation (informatique)
[Termes IGN] modèle numérique de surface
[Termes IGN] regroupement de points
[Termes IGN] visibilitéRésumé : (Auteur) Least visible path analysis is a basic function in terrain visibility analysis. However, current least visible path planning is constrained to least-cost path computing on a cost surface obtained from visibility information of all the terrain points on digital elevation models. This kind of method ignores the visibility correlation caused by the overlapped part of the adjacent points' reverse viewsheds. With regard to such a correlation, this paper proposes a new method using the amalgamation of reverse viewsheds to find an optimal path with the minimal visibility dominance. Both methods are implemented using C++ programming, and the experimental results show that the new method produces more accurate least visible paths than the traditional one does. Numéro de notice : A2008-225 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1080/13658810701602062 En ligne : https://doi.org/10.1080/13658810701602062 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29220
in International journal of geographical information science IJGIS > vol 22 n° 6-7 (june 2008) . - pp 645 - 656[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 Approximating the visible region of a point on a terrain / B. Ben-Moshe in Geoinformatica, vol 12 n° 1 (March - May 2008)
[article]
Titre : Approximating the visible region of a point on a terrain Type de document : Article/Communication Auteurs : B. Ben-Moshe, Auteur ; P. Carmi, Auteur ; M.J. Katz, Auteur Année de publication : 2008 Article en page(s) : pp 21 - 36 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géomatique
[Termes IGN] approximation
[Termes IGN] interpolation
[Termes IGN] Triangulated Irregular Network
[Termes IGN] visibilitéRésumé : (Auteur) Given a terrain and a point p on or above it, we wish to compute the region Rp that is visible from p. We present a generic radar-like algorithm for computing an approximation of Rp. The algorithm interpolates the visible region between two consecutive rays (emanating from p) whenever the rays are close enough; that is, whenever the difference between the sets of visible segments along the cross sections in the directions specified by the rays is below some threshold. Thus the density of the sampling by rays is sensitive to the shape of the visible region. We suggest a specific way to measure the resemblance (difference) and to interpolate the visible region between two consecutive rays. We also present an alternative algorithm, which uses circles of increasing radii centered at p instead of rays emanating from p. Both algorithms compute a representation of the (approximated) visible region that is especially suitable for is-visible-from-p queries, i.e., given a query point q on the terrain determine whether q is visible from p. Finally, we report on the experiments that we performed with these algorithms and with their corresponding fixed versions, using a natural error measure. Our main conclusion is that the radar-like algorithm is significantly better than the others. Copyright Springer Numéro de notice : A2008-068 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1007/s10707-006-0017-5 En ligne : https://doi.org/10.1007/s10707-006-0017-5 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29063
in Geoinformatica > vol 12 n° 1 (March - May 2008) . - pp 21 - 36[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 057-08011 RAB Revue Centre de documentation En réserve L003 Disponible Visibility prediction based on artificial neural networks used in automatic network design / M. Saadatseresht in Photogrammetric record, vol 22 n° 120 (December 2007 - February 2008)
[article]
Titre : Visibility prediction based on artificial neural networks used in automatic network design Type de document : Article/Communication Auteurs : M. Saadatseresht, Auteur ; Masood Varshosaz, Auteur Année de publication : 2007 Article en page(s) : pp 336 - 355 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Photogrammétrie numérique
[Termes IGN] apprentissage automatique
[Termes IGN] incertitude des données
[Termes IGN] photogrammétrie terrestre
[Termes IGN] réseau neuronal artificiel
[Termes IGN] visibilitéRésumé : (Auteur) Automatic design of photogrammetric networks is a complex task for which the visibility and quality constraints need to be both modelled and satisfied simultaneously. The task becomes even more complex when measurements are carried out for the first time on a large and/or complex object surrounded by multiple obstructions in a confined workspace. In this situation, automatic visibility prediction of a target point becomes an extremely difficult task. The visibility information inherent within the initial photogrammetric network can be used to solve this problem. However, this introduces some uncertainty into the prediction result because of the incompleteness of the visibility information. In a previous study, the authors developed an analytical deterministic method, visibility uncertainty prediction (VUP), that used ‘‘visibility spheres’’ to predict the visibility of target points. This paper investigates the use of artificial neural networks (ANNs) in visibility prediction, and presents a new technique, ANN-based visibility uncertainty prediction (AVUP), that works by training a feed-forward multi-layer ANN. The visibility data for this network is extracted from the initial photogrammetric network. Once trained, the network can be used to predict the visibility of any target point from a potential camera station. Various experiments were carried out to evaluate the proposed technique. The results showed that, compared to the previous deterministic method, it is more accurate and has a lower computational cost. Copyright RS&PS + Blackwell Publishing Numéro de notice : A2007-569 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1111/j.1477-9730.2007.00454.x En ligne : https://doi.org/10.1111/j.1477-9730.2007.00454.x Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28932
in Photogrammetric record > vol 22 n° 120 (December 2007 - February 2008) . - pp 336 - 355[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 106-07041 Revue Centre de documentation Revues en salle Disponible Multi-visibility of triangulated terrains / N. Coll in International journal of geographical information science IJGIS, vol 21 n° 9-10 (october 2007)
[article]
Titre : Multi-visibility of triangulated terrains Type de document : Article/Communication Auteurs : N. Coll, Auteur ; M. Fort, Auteur ; et al., Auteur Année de publication : 2007 Article en page(s) : pp 1115 - 1134 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications SIG
[Termes IGN] base de données multi-représentation
[Termes IGN] point de visibilité
[Termes IGN] système d'information géographique
[Termes IGN] Triangulated Irregular Network
[Termes IGN] visibilité
[Termes IGN] visualisation cartographiqueRésumé : (Auteur) Visibility computation on terrain models is an important research topic with many applications in Geographical Information Systems. A multi-visibility map is the subdivision of the domain of a terrain into regions that, according to different criteria, encodes the visibility with respect to a set of view elements. We present an approach for visualising approximated multi-visibility maps of a triangulated terrain corresponding to a set of view elements by using graphics hardware. Our method supports heterogeneous sets of view elements containing points, segments, polygonal chains and polygons and works for weak and strong visibility. Moreover, we are also able to efficiently solve approximated point and polygonal region multi-visibility queries. To illustrate the usefulness of our approach we present results obtained with an implementation of the proposed algorithms. Copyright Taylor & Francis Numéro de notice : A2007-559 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/13658810701300097 En ligne : https://doi.org/10.1080/13658810701300097 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28922
in International journal of geographical information science IJGIS > vol 21 n° 9-10 (october 2007) . - pp 1115 - 1134[article]Exemplaires(2)
Code-barres Cote Support Localisation Section Disponibilité 079-07061 RAB Revue Centre de documentation En réserve L003 Disponible 079-07062 RAB Revue Centre de documentation En réserve L003 Disponible Road safety analysis / Vassilis Pagounis in GIM international, vol 21 n° 8 (August 2007)
[article]
Titre : Road safety analysis Type de document : Article/Communication Auteurs : Vassilis Pagounis, Auteur ; M. Tsakiri, Auteur ; S. Palaskas, Auteur Année de publication : 2007 Article en page(s) : pp 52 - 53 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] accident de la route
[Termes IGN] étude préalable
[Termes IGN] lasergrammétrie
[Termes IGN] réseau routier
[Termes IGN] sécurité routière
[Termes IGN] télémétrie laser terrestre
[Termes IGN] trafic routier
[Termes IGN] visibilitéRésumé : (Auteur) With the growing interest in (inter)national road safety programs comes a need for documentation of road systems for safety analysis and traffic-accident reconstruction studies. This requires reliable, accurate and timely data, which, as the authors demonstrate, Terrestrial Laser Scanning (TLS) can provide. Copyright Reed Business Information Numéro de notice : A2007-330 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28693
in GIM international > vol 21 n° 8 (August 2007) . - pp 52 - 53[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 061-07081 RAB Revue Centre de documentation En réserve L003 Disponible Modeling visibility through vegetation / M. Llobera in International journal of geographical information science IJGIS, vol 21 n° 6-7 (july 2007)PermalinkEtude pour la réalisation de cartes de visibilité satellitaire GNSS / G. Bizouard in XYZ, n° 111 (juin - août 2007)PermalinkModelling and prediction of GPS availability with digital photogrammetry and LiDAR / Georges E. Taylor in International journal of geographical information science IJGIS, vol 21 n° 1-2 (january 2007)PermalinkA layered stereo matching algorithm using segmentation and global visibility constraints / M. Bleyer in ISPRS Journal of photogrammetry and remote sensing, vol 59 n° 3 (May 2005)PermalinkProceedings of the GIS Research UK, 13th Annual Conference, GISRUK 2005, 6-8 April 2005, Geography & Geomatics, University of Glasgow / Roland Billen (2005)PermalinkK-guarding of polyhedral terrain / B. Kaucic in International journal of geographical information science IJGIS, vol 18 n° 7 (november 2004)PermalinkVisibility analysis in vision metrology network design / M. Saadatseresht in Photogrammetric record, vol 19 n° 107 (September - November 2004)PermalinkRemote sensing and spatial data: the establishment and visualisation of 3D computer landscape models as basis for visual impact assessment / B. Koch in GIS Geo-Informations-Systeme, vol 2001 n° 12 (Dezember 2001)PermalinkAccuracy of the Canadian digital terrain data in the Gatineau Region of Quebec / Rob Reeves in Geomatica, vol 55 n° 1 (March 2001)PermalinkThe mapping of terrain visibility / D.R. Miller in Cartographic journal (the), vol 34 n° 2 (December 1997)Permalink