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Objets géographiques et simulation agent : entre thématique et méthodologie / Léna Sanders in Revue internationale de géomatique, vol 17 n° 2 (juin – août 2007)
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Titre : Objets géographiques et simulation agent : entre thématique et méthodologie Type de document : Article/Communication Auteurs : Léna Sanders, Auteur Année de publication : 2007 Article en page(s) : pp 135 - 160 Note générale : Bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] interaction spatiale
[Termes IGN] modélisation spatiale
[Termes IGN] niveau d'analyse
[Termes IGN] simulation
[Termes IGN] système multi-agentsRésumé : (Auteur) L'objet de cet article est de discuter des changements apportés par l'approche agent dans la modélisation en géographie. Les questions de choix d'un niveau de modélisation, de forme des relations entre différents niveaux, de prise en compte de la diversité des entités élémentaires et de l'articulation des processus bottom-up et top-down sont abordées à partir de plusieurs exemples. L'accent est mis sur les nuances qu'induisent les points de vue thématique et méthodologique sur ces questions. Copyright Hermès Numéro de notice : A2007-350 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.3166/rig.17.135-160 En ligne : https://doi.org/10.3166/rig.17.135-160 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28713
in Revue internationale de géomatique > vol 17 n° 2 (juin – août 2007) . - pp 135 - 160[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 047-07021 RAB Revue Centre de documentation En réserve L003 Disponible Analysis of a possible future degradation in the DORIS geodetic results related to changes in the satellite constellation / Pascal Willis in Advances in space research, vol 39 n° 10 (May 2007)
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Titre : Analysis of a possible future degradation in the DORIS geodetic results related to changes in the satellite constellation Type de document : Article/Communication Auteurs : Pascal Willis , Auteur Année de publication : 2007 Article en page(s) : pp 1582 - 1588 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] données DORIS
[Termes IGN] DORIS
[Termes IGN] International Terrestrial Reference Frame
[Termes IGN] rotation de la Terre
[Termes IGN] secteur spatial
[Termes IGN] simulation numériqueRésumé : (auteur) Recently, several improvements were made in the DORIS data processing at the IGN/JPL (Institut Geographique National, France; Jet Propulsion Laboratory, California Institute of Technology, USA) analysis center: use of GRACE-derived gravity fields, data preprocessing and station discontinuity detection, etc. This allowed enhanced performances for ground station geodetic positioning (typically 10 mm using a week of data), as well as for polar motion (0.5–1.0 mass for daily determination). However, since the loss in 2004 of the DORIS receiver on the TOPEX/Poseidon mission, only four satellites (SPOT-2, SPOT-4, SPOT-5, and ENVISAT) are currently equipped with DORIS receivers. Furthermore, most of them are aging and some have already far exceeded their expected lifetime. The goal of this paper is to analyze how the geodetic performances could be degraded in the future if one or more of these satellites would unfortunately be lost, and to envisage which satellites are currently the most critical in the DORIS geodetic performances. We have reanalyzed 1 year of recent DORIS data (2005), processing all possible combinations of satellite constellation sub-sets. We then compared these results (station coordinates and polar motion) with those obtained in regular data processing when using DORIS data from all four available satellites in 2005. We demonstrate the importance of the SPOT-5 data, equipped with a new type of on-board DORIS receiver. The study also shows some possible weaknesses in our current ENVISAT orbit computations. Fortunately, new DORIS satellites are also expected in the near future (Jason-2, CRYOSAT-2 and AltiKa), which could improve current DORIS-derived geodetic results due to their specific type of orbit (different from the SPOT sun-synchronous orbits) and also to enhanced on-board receivers. Numéro de notice : A2007-659 Affiliation des auteurs : IGN (1940-2011) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.asr.2006.11.018 Date de publication en ligne : 09/06/2007 En ligne : https://doi.org/10.1016/j.asr.2006.11.018 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102695
in Advances in space research > vol 39 n° 10 (May 2007) . - pp 1582 - 1588[article]Modelling landscape dynamics with Python / D. Karssenberg in International journal of geographical information science IJGIS, vol 21 n° 5 (may 2007)
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Titre : Modelling landscape dynamics with Python Type de document : Article/Communication Auteurs : D. Karssenberg, Auteur ; K. de Jong, Auteur ; J. Van Der Kwast, Auteur Année de publication : 2007 Article en page(s) : pp 483 - 495 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes d'information géographique
[Termes IGN] calcul matriciel
[Termes IGN] données maillées
[Termes IGN] méthode de Monte-Carlo
[Termes IGN] modèle dynamique
[Termes IGN] modélisation 3D
[Termes IGN] propagation d'erreur
[Termes IGN] Python (langage de programmation)
[Termes IGN] simulation
[Termes IGN] visualisation de donnéesRésumé : (Auteur) A new tool for construction of models is presented that allows earth scientists without specialist knowledge in programming to convert theories to numerical computer models simulating landscape change through time. This tool, referred to as the PCRaster Python library, consists of: (1) the standard Python programming language, which is a generic, interpreted scripting language, supporting object oriented programming; (2) a large set of spatial and temporal functions on raster maps that are embedded in the Python language as an extension; (3) a framework provided as a Python class to construct and run iterative temporal models and to calculate error propagation with Monte Carlo simulation; and (4) visualization routines to display spatio-temporal data read and written by this framework. Python is a high-level programming language, and users of the tool do not have to be specialist computer programmers. Users of the PCRaster Python library can take advantage of several other Python libraries, such as extensions for matrix algebra and for modelling in three spatial dimensions. Copyright Taylor & Francis Numéro de notice : A2007-132 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article DOI : 10.1080/13658810601063936 En ligne : https://doi.org/10.1080/13658810601063936 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28495
in International journal of geographical information science IJGIS > vol 21 n° 5 (may 2007) . - pp 483 - 495[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-07031 RAB Revue Centre de documentation En réserve L003 Disponible 079-07032 RAB Revue Centre de documentation En réserve L003 Disponible A probabilistic framework for representing and simulating uncertain environmental variables / Gerard B.M. Heuvelink in International journal of geographical information science IJGIS, vol 21 n° 5 (may 2007)
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Titre : A probabilistic framework for representing and simulating uncertain environmental variables Type de document : Article/Communication Auteurs : Gerard B.M. Heuvelink, Auteur ; J. Brown, Auteur ; E. Emiel Van Loon, Auteur Année de publication : 2007 Article en page(s) : pp 497 - 513 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Information géographique
[Termes IGN] distribution, loi de
[Termes IGN] incertitude d'attribut
[Termes IGN] incertitude de position
[Termes IGN] incertitude des données
[Termes IGN] modèle stochastique
[Termes IGN] simulationRésumé : (Auteur) Understanding the limitations of environmental data is important for managing environmental systems effectively and for encouraging the responsible use of uncertain data. Explicit assessment of the uncertainties associated with environmental data, and their storage in a database, are therefore important. This paper presents a statistical framework for representing and simulating uncertain environmental variables. In general terms, an uncertain variable is completely specified by its probability distribution function (pdf). Pdfs are developed for objects with uncertain locations ('positional uncertainty') and uncertain attribute values ('attribute uncertainty'). Objects comprising multiple space-time locations are separated into 'rigid objects', where positional uncertainty cannot alter the internal geometry of the object, and 'deformable' objects, where positional uncertainty can vary between locations in one object. Statistical dependence is allowed between uncertainties in multiple locations in one object. The uncertainties associated with attribute values are also modelled with pdfs. The type and complexity of these pdfs depend upon the measurement scale and the space-time variability of the uncertain attribute. The framework is illustrated with examples. A prototype software tool for assessing uncertainties in environmental data, storing them within a database, and for generating realizations for use in Monte Carlo studies is also presented. Copyright Taylor & Francis Numéro de notice : A2007-133 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/13658810601063951 En ligne : https://doi.org/10.1080/13658810601063951 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28496
in International journal of geographical information science IJGIS > vol 21 n° 5 (may 2007) . - pp 497 - 513[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-07031 RAB Revue Centre de documentation En réserve L003 Disponible 079-07032 RAB Revue Centre de documentation En réserve L003 Disponible Spatial-temporal specific neighbourhood rules for cellular automata land-use modelling / Stan Geertman in International journal of geographical information science IJGIS, vol 21 n° 5 (may 2007)
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Titre : Spatial-temporal specific neighbourhood rules for cellular automata land-use modelling Type de document : Article/Communication Auteurs : Stan Geertman, Auteur ; M. Hagoort, Auteur ; Henk F.L. Ottens, Auteur Année de publication : 2007 Article en page(s) : pp 547 - 568 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] analyse diachronique
[Termes IGN] automate cellulaire
[Termes IGN] carte d'occupation du sol
[Termes IGN] Kappa de Cohen
[Termes IGN] modélisation spatiale
[Termes IGN] occupation du sol
[Termes IGN] simulation
[Termes IGN] spatial metrics
[Termes IGN] voisinage (relation topologique)Résumé : (Auteur) This paper explores the necessity of using spatial-temporal specific neighbourhood rules for simulation of urban dynamics at a regional level with the help of a Cellular Automata (CA) land-use model (Environment Explorer). Moreover, it explores a method for formulating these spatial-temporal specific neighbourhood rules. Therein, spatial metrics originating from the field of landscape ecology prove to be very useful, in particular the so-called enrichment factor. Analysis of historical data with the help of these spatial metrics revealed evidence of substantial differences in land-use developments between time periods and regions, for example, differences that should be incorporated in land-use models if applied on a more detailed regional scale. In a case study, micro-scale land-use data incorporated in a CA-model were used to analyse and simulate the urban morphological changes over two time periods in four urban regions in the Netherlands. In this study, regional and time-specific neighbourhood rules performed significantly better than a set of generic neighbourhood rules. In contrast, within current practice, most CA land-use modelling makes use of only one uniform set of neighbourhood rules for performing both large area and regional scale land-use simulations. This study questions this common practice and puts it into perspective. Moreover, it indicates some restrictions in the proposed regionalization of the neighbourhood rules; one which is particularly noteworthy is its time-specific dependency of local developments and circum--stances. Copyright Taylor & Francis Numéro de notice : A2007-136 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article DOI : 10.1080/13658810601064892 En ligne : https://doi.org/10.1080/13658810601064892 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28499
in International journal of geographical information science IJGIS > vol 21 n° 5 (may 2007) . - pp 547 - 568[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-07031 RAB Revue Centre de documentation En réserve L003 Disponible 079-07032 RAB Revue Centre de documentation En réserve L003 Disponible Development of a practical photogrammetric network design using evolutionary computing / G. Olague in Photogrammetric record, vol 22 n° 117 (March - May 2007)PermalinkEvaluating the uncertainty caused by Post Office Box addresses in environmental health studies: A restricted Monte Carlo approach / X. Shi in International journal of geographical information science IJGIS, vol 21 n° 3-4 (march - april 2007)PermalinkMéthodes probabilistes pour la reconstruction de données manquantes / B. Beauzamy (2007)PermalinkGABRIEL: Gis activity-based travel simulator, activity scheduling in the presence of real-time information / Mei-Po Kwan in Geoinformatica, vol 10 n° 4 (December 2006)PermalinkIntegration of MODIS data into a simple model for the spatial distributed simulation of soil water content and evapotranspiration / Y. Zhang in Remote sensing of environment, vol 104 n° 4 (30/10/2006)PermalinkDeveloping land use/land cover parameterization for climate-land modelling in East Africa / Nathan Torbick in International Journal of Remote Sensing IJRS, vol 27 n°18 - 19 - 20 (October 2006)PermalinkAgent-based modelling of shifting cultivation field patterns, Vietnam / M.R. Jepsen in International journal of geographical information science IJGIS, vol 20 n° 9 (october 2006)PermalinkA simulation study of the errors of omission and commission for GRACE RL01 gravity fields / B. Gunter in Journal of geodesy, vol 80 n° 7 (October 2006)PermalinkHigh-resolution change estimation of soil moisture using L-band radiometer and Radar observations made during the SMEX02 experiments / U. Narayan in IEEE Transactions on geoscience and remote sensing, vol 44 n° 6 (June 2006)PermalinkSimulation d'un SIG de la distribution spatiale de polluants / M. Erunova in Géomatique expert, n° 51 (01/06/2006)Permalink