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Une grille de lecture pour l'analyse des formes du peuplement en Europe : l'apport d'une méthode de lissage par potentiels / E. Dumas in Revue internationale de géomatique, vol 11 n°3-4 (septembre 2001 - février 2002)
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Titre : Une grille de lecture pour l'analyse des formes du peuplement en Europe : l'apport d'une méthode de lissage par potentiels Type de document : Article/Communication Auteurs : E. Dumas, Auteur ; Marianne Guérois, Auteur Année de publication : 2001 Article en page(s) : pp 405 - 421 Note générale : Bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Systèmes d'information géographique
[Termes IGN] densité de population
[Termes IGN] données démographiques
[Termes IGN] Europe (géographie politique)
[Termes IGN] lissage de données
[Termes IGN] populationRésumé : (Auteur) Cet article présente l'intérêt d'une méthode de lissage par potentiels pour cartographier les formes du peuplement en Europe à plusieurs niveaux d'analyse. L'application de cette méthode à la région transfrontalière franco-belge permet de poser les bases d'une grille de lecture transposable à d'autres espaces européens. Numéro de notice : A2001-177 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article DOI : sans En ligne : https://archives-rig.revuesonline.com/article.jsp?articleId=471 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=21872
in Revue internationale de géomatique > vol 11 n°3-4 (septembre 2001 - février 2002) . - pp 405 - 421[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 047-01031 RAB Revue Centre de documentation En réserve L003 Disponible Machine learning techniques for determining parameters of cartographic generalisation algorithms / Lagrange (Enseigne de Vaisseau) (2000)
Titre : Machine learning techniques for determining parameters of cartographic generalisation algorithms Type de document : Article/Communication Auteurs : Lagrange (Enseigne de Vaisseau), Auteur ; Landras (Enseigne de Vaisseau), Auteur ; Sébastien Mustière , Auteur Editeur : International Society for Photogrammetry and Remote Sensing ISPRS Année de publication : 2000 Collection : International Archives of Photogrammetry, Remote Sensing and Spatial Information Sciences, ISSN 1682-1750 num. 33-B4 Conférence : ISPRS 2000, 19th ISPRS Congress Technical Commission 4, Mapping and Geographic Information Systems 16/07/2000 23/07/2000 Amsterdam Pays-Bas OA Proceedings archives Importance : pp 718 - 725 Format : 21 x 30 cm Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] 1:250.000
[Termes IGN] apprentissage automatique
[Termes IGN] BD Carto
[Termes IGN] carte routière
[Termes IGN] lissage de données
[Vedettes matières IGN] GénéralisationRésumé : (auteur) This paper reports on research performed in the field of automated map generalization. We address the issue of determining how to set parameters of transformation algorithms. Empirical and theoretical studies have shown that, even given fixed map scale and purpose, these parameter values vary from one object to the other according to different characteristics such as the shape, size or environment of the object. Because of the complexity of cartographic rules and generalisation algorithms, we address this problem with techniques developed in the field of Machine Learning from examples. Specifically, we automatically learn, with neural networks, how to determine an algorithm parameters according to a set of measures describing the object to be transformed. We present the main issues to be addressed to use neural networks. We show that our approach is useful and that its main limit stands in the lack of good measures to describe an object. As a case study, this paper presents results of learning how to set the strength of a smoothing algorithm on a line from the French BDCarto database to represent a road on a 1/250,000 scale road map. Numéro de notice : C2000-029 Affiliation des auteurs : COGIT+Ext (1988-2011) Thématique : GEOMATIQUE Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : sans En ligne : https://www.isprs.org/proceedings/XXXIII/congress/part4/718_XXXIII-part4.pdf Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=103272 Regionale und globale Gravitationsfeldanalyse hochauflösender Satellitendaten mittels Mehrgitterverfahren / S. Rudolph (2000)
Titre : Regionale und globale Gravitationsfeldanalyse hochauflösender Satellitendaten mittels Mehrgitterverfahren Titre original : [Analyse du champ de gravitation régional et global des satellites à haute résolution grâce à des méthodes multi grilles] Type de document : Thèse/HDR Auteurs : S. Rudolph, Auteur Editeur : Munich : Bayerische Akademie der Wissenschaften Année de publication : 2000 Collection : DGK - C Sous-collection : Dissertationen num. 528 Importance : 76 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-7696-9567-0 Langues : Allemand (ger) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] champ de gravitation
[Termes IGN] champ de pesanteur terrestre
[Termes IGN] discrétisation
[Termes IGN] données GOCE
[Termes IGN] données GRACE
[Termes IGN] gradiométrie
[Termes IGN] lissage de données
[Termes IGN] poursuite de satelliteIndex. décimale : 30.42 Gravimétrie Résumé : (Auteur) This thesis investigates the use of multigrid methods in conjunction with gravity field recovery from satellite data. The applied methods represent not only very fast techniques for solving large and non-sparse equation systems, but also yield approximations of the gravity field on different discretization levels. This theme becomes more and more acute because of different dedicated satellite missions. They will provide almost globally distributed gravity field information of unprecedented resolution and precision. Therefore new strategies for using this information have to be developed.
In contrast to the methods based on spherical harmonics a parameterization with space-localizing base functions on a sequence of hierarchically chosen grids is used. The investigation of the unavoidable discretization errors follows. The observation equations in the case of satellite-to-satellite tracking as well as in the case of satellite gravity gradiometry are formulated. The estimation of the unknown coefficients leads to ill-conditioned and fully occupied normal equation systems. A regularization technique has to be applied in order to solve them using the multigrid methods. The transformations between the levels of discretization and the different smoothing operators are dealt with. These operators are compared in the convergence analysis and the dependence upon the ordering of the unknowns is demonstrated.
The gravity field recovery based on the developed methods is examined in simulations concerning the dedicated missions CHAMP, GRACE and GOCE. The global investigations in the case of GRACE show that the L-curve is a proper method for choosing the regularization parameter. In addition the CHAMP simulation demonstrates the effective use of this parameter determination procedure for iteration techniques. The combination of different discretization levels is a main feature of the developed method. Its application in the simulation concerning GOCE leads to a regional refinement, when the estimated gravity field of GRACE is used as a-priori information.Numéro de notice : 27823 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Thèse étrangère Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=56447 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 27823-01 30.42 Livre Centre de documentation Géodésie Disponible Modelling and Inversion of High Precision Gravity Data / E. Lewi (1997)
Titre : Modelling and Inversion of High Precision Gravity Data Type de document : Thèse/HDR Auteurs : E. Lewi, Auteur Editeur : Munich : Bayerische Akademie der Wissenschaften Année de publication : 1997 Collection : DGK - C Sous-collection : Dissertationen num. 471 Importance : 145 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-7696-9511-3 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] anomalie de pesanteur
[Termes IGN] champ de pesanteur local
[Termes IGN] Darmstadt
[Termes IGN] gradient de gravitation
[Termes IGN] levé gravimétrique
[Termes IGN] lissage de données
[Termes IGN] matrice
[Termes IGN] problème inverse
[Termes IGN] tour (bâtiment)Index. décimale : 30.42 Gravimétrie Résumé : (Auteur) In this work, the scope of the present day gravity data acquisition, processing and interpretational technique in using weak signal gravity anomalies, to study mass distributions, has been tested. To carry out this test, measurements were taken in Darmstadt and Bremen. The study in these areas, that encompasses the different stages of gravity data measurement, analysis and modelling procedures, has led to the development of some new methods and algorithms. The survey in Darmstadt was aimed at recovering the shape, location and density of two Rain Water Reservoirs, from measured gravity data. On the other hand the survey in Bremen was aimed at computing the vertical component of the gravity gradient within the "Drop Tower Bremen".
At first, the implementation of a spectral analysis technique in choosing a sampling interval that avoided aliasing effects was discussed and demonstrated, using the data in the Darmstadt survey area. The simulation of data, for this analysis, was partially carried out using an algorithm that can compute the gravitational attraction of cylindrically shaped bodies. This algorithm, which has reduced the well-known problem in computing the gravitational attraction of vertical cylinders on points that lie outside the axis of symmetry, is developed based on an existing theoretical relationship. The effectiveness of this algorithm was also tested in modelling the effect of the different steal and concrete structures in the "Drop Tower Bremen". Besides this, the need to apply a modified terrain correction procedure for data measured at a certain height above the surface of the ground has been shown.
One of the major findings of this study, is the development of a trend analysis method that makes use of the polynomial fitting technique. This technique is advantageous in its capability to suppress the role of the residual in determining the trend surface. Especially its capability to incorporate a priori information about the trend surface enables the modelling procedure to focus on the trend surface only. In addition, the method estimates the densities for the Bouguer and terrain reductions in an environment where all other effects, other than the elevation dependant term, are modelled using different polynomial terms. In conjunction with this, the role of anomalous gradient effect in gravity data interpretation has been discussed and its effect in the Darmstadt survey area has been analysed.
The other major finding of the present study is the development of a three-dimensional gravity inversion technique. This method makes use of diagonal weighting matrices to reduce the need for large computer memory and to save large computational time. Besides this, the use of a priori information together with a regularization method that depends on the misfit between the measured and model data iteratively, leads to the desired stable solution. Based on this three-dimensional gravity inversion method, a software which can be used for different applications has been developed. The test made on simulated data and the field gravity data, in the Darmstadt survey area, showed the effectiveness of the method both in error-free and error contaminated data. The test made on error-free data, simulated by simple shape three-dimensional models, particularly showed the capability of the method in recovering the causative body using a minimal amount of a priori information. The inversion of measured gravity data taken from the Darmstadt survey area showed not only the effectiveness of the inversion method but also the ability of the present day gravity data interpretation technique in analysing weak signal gravity anomalies.
The comparison of the upward continued gravity data and that measured at different heights of the "Drop Tower Bremen" confirmed the validity of Newton's inverse square law, within the accuracy of the survey. Moreover, through the use of this comparison between the measured and analytically continued gravity data, the vertical component of the gravity gradient has been computed with high accuracy. In general, the study in both the Darmstadt and Bremen survey areas showed that the gravity method, if effectively used, can serve as a tool in locating mass distributions, even if these masses generate only weak signal gravity anomalies.Numéro de notice : 28023 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Thèse étrangère Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=63370 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 28023-01 30.42 Livre Centre de documentation Géodésie Disponible 28023-02 30.42 Livre Centre de documentation Géodésie Disponible Mechanical approach of generalisation / Emmanuel Fritsch (1996)
Titre : Mechanical approach of generalisation Type de document : Article/Communication Auteurs : Emmanuel Fritsch , Auteur Editeur : Londres : Association for Geographic Information AGI Année de publication : 1996 Conférence : GISRUK 1996, 4th GIS research UK annual conference 10/04/1996 12/04/1996 Canterbury - Kent Royaume-Uni OA Proceedings archives Importance : pp 49 - 55 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] généralisation cartographique automatisée
[Termes IGN] lissage de données
[Termes IGN] objet géographique linéaire
[Vedettes matières IGN] GénéralisationNuméro de notice : C1996-019 Affiliation des auteurs : COGIT (1988-2011) Thématique : GEOMATIQUE/INFORMATIQUE Nature : Communication Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=65638 Digital image processing / Rafael C. Gonzalez (1993)PermalinkArea-patch generalisation: a competitive approach / Jean-Claude Müller in Cartographic journal (the), vol 29 n° 2 (December 1992)PermalinkAutomatisation de l'extraction du réseau routier sur cartes JOG digitalisées / Marc Pierrot-Deseilligny (1991)PermalinkAn adaptive noise smoothing filter for remotely-sensed images with microphonic noise / S. Cheng in International Journal of Remote Sensing IJRS, vol 10 n° 6 (June 1989)PermalinkEstimation and spectral analysis / J.A.R. Blais (1988)PermalinkMéthodes d'estimations de surfaces à partir d'une image numérique / J. Couronne (1988)PermalinkOn the great circle reduction in the data analysis for the astrometric satellite Hipparcos / Hans van der Marel (1988)PermalinkEtude géographique de la côte nord du Sénégal à partir des données satellitaires MOMS-1 / A.T. Diaw in Bulletin [Société Française de Photogrammétrie et Télédétection], n° 108 (Octobre 1987)PermalinkSmoothing vegetation index profiles : an alternative method for reducing radiometric disturbance in NOAA-AVHRR data / A.V. Dijkt in Photogrammetric Engineering & Remote Sensing, PERS, vol 53 n° 8 (august 1987)PermalinkDigital image processing / Rafael C. Gonzalez (1987)PermalinkSériation visuelle et sériation automatique / Jean-Claude Müller in Annuaire international de cartographie, n° 24 (1984)PermalinkDigital image processing / Rafael C. Gonzalez (1983)PermalinkDigital picture processing, 1. Volume 1 / Azriel Rosenfeld (1982)PermalinkSpatial statistics / B.D. Ripley (1981)PermalinkStudie zur Erfassung und Verarbeitung von Meßdaten dynamischer Systeme / N. Felgendreher (1981)PermalinkIRMS : un programme interactif de traitement d'image d'IBM-France / G. Savary in Bulletin [Société Française de Photogrammétrie et Télédétection], n° 78 (Avril 1980)PermalinkDigital image processing / Rafael C. Gonzalez (1977)PermalinkLissage des observations par la méthode de Whittaker-Robinson-Vondrak / P. Paquet (1974)PermalinkKombination von Doppler-, Laser- und photographischen Beobachtungen in Satellitennetzen / J. Campbell (1973)PermalinkLa pose des équations fondamentales dans les systèmes de moindres carrés / Henri Marcel Dufour (1963)Permalink