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Merging R-trees: efficient strategies for local bulk insertion / L. Chen in Geoinformatica, vol 6 n° 1 (March - May 2002)
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Titre : Merging R-trees: efficient strategies for local bulk insertion Type de document : Article/Communication Auteurs : L. Chen, Auteur ; R. Choubey, Auteur ; E.A. Rundensteiner, Auteur Année de publication : 2002 Article en page(s) : pp 7 - 34 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] arbre-R
[Termes IGN] index spatial
[Termes IGN] indexation spatiale
[Termes IGN] intégration de données
[Termes IGN] jeu de données localisées
[Termes IGN] requête spatialeRésumé : (Auteur) A lot of recent work has focussed on bulk loading of data into multidimensional index structures in order to efficiently construct such structures for large data sets. In this paper, we address this problem with particular focus on R-trees - which are an important class of index structures used widely in commercial database systems. We propose a new technique, which as opposed to the current technique of inserting data one by one, bulk inserts entire new data sets into an active R-tree. This technique, called STLT (for small-tree-large-tree), considers the new data set as an R-tree itself (small tree), identifies and prepares a suitable location in the original R-tree (large tree) for insertion, and lastly performs the insert of the small tree into the large tree. Besides an analytical cost model of STLT, extensive experimental studies both on synthetic and real GIS data sets are also reported. These experiments not only compare STLT against the conventional technique, but also evaluate the suitability and limitations of STLT under different conditions, such as varying buffer sizes, ratio between existing and new data sizes, and skewness of new data with respect to the whole spatial region. We find that STLT does much better (in average, about 65%) than the existing technique for skewed data sets as well for large sizes of both the large tree and the small tree in terms of insertion time, while keeping comparable query tree quality. STLT consistently outperforms the alternate technique in all other circumstances in terms of bulk insertion time, especially, even up to 2,000% for the cases when the area of new data sets covers up to 4% of the global region covered by the existing index tree; however, at the cost of a deteriorating resulting tree quality. Numéro de notice : A2002-107 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article DOI : 10.1023/A:1013764014000 En ligne : https://doi.org/10.1023/A:1013764014000 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=22022
in Geoinformatica > vol 6 n° 1 (March - May 2002) . - pp 7 - 34[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 057-02011 RAB Revue Centre de documentation En réserve L003 Disponible Modelling a discrete spatial response using generalized linear mixed models: application to Lyme disease vectors / Abhik Das in International journal of geographical information science IJGIS, vol 16 n° 2 (march 2002)
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Titre : Modelling a discrete spatial response using generalized linear mixed models: application to Lyme disease vectors Type de document : Article/Communication Auteurs : Abhik Das, Auteur ; S.R. Lele, Auteur ; G.E. Glass, Auteur ; T. Shields, Auteur ; J. Patz, Auteur Année de publication : 2002 Article en page(s) : pp 151 - 166 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] corrélation automatique de points homologues
[Termes IGN] distribution de Poisson
[Termes IGN] distribution spatiale
[Termes IGN] maladie bactérienne
[Termes IGN] modélisation spatialeRésumé : (Auteur) Predicting disease risk by identifying environmental factors responsible for the geographical distribution of disease vectors can help target control strategies and optimize preventive measures. In this study we present a hierarchical approach to model the distribution of Lyme disease ticks as a function of environmental factors. We use the Poisson framework natural for count data while allowing for spatial correlations. To help identify environmental factors that best explain tick abundance, we develop an intuitive procedure for covariate selection in the spatial context. These methods could be useful in analysing effects of environmental and climatological changes on the distribution of disease vectors, and the spatial extrapolation of vector abundance under such scenarios. Numéro de notice : A2002-025 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article DOI : 10.1080/13658810110099134 En ligne : https://doi.org/10.1080/13658810110099134 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=21942
in International journal of geographical information science IJGIS > vol 16 n° 2 (march 2002) . - pp 151 - 166[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-02021 RAB Revue Centre de documentation En réserve L003 Disponible Optimized resource allocation for GIS-based model implementation / M. Crosetto in Photogrammetric Engineering & Remote Sensing, PERS, vol 68 n° 3 (March 2002)
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Titre : Optimized resource allocation for GIS-based model implementation Type de document : Article/Communication Auteurs : M. Crosetto, Auteur ; F. Crosetto, Auteur ; S. Tarantola, Auteur Année de publication : 2002 Article en page(s) : pp 225 - 232 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] aide à la décision
[Termes IGN] analyse de sensibilité
[Termes IGN] implémentation (informatique)
[Termes IGN] incertitude des données
[Termes IGN] modèle conceptuel de donnéesRésumé : (Auteur) This paper focuses on a new procedure to support the planning and implementation of GIS-based models. Critical decisions are often based on the outputs of such models. A major goal of the GIS planning stage is to implement a model whose output can reliably support the decision process. The procedure allows the above goal to be achieved with an optimized allocation of resources for GIS data acquisition. It is based on two important modeling tools: uncertainty analysis and sensitivity analysis. An application of the procedure to a GIS-based hydrologic model for flood forecasting is discussed. Numéro de notice : A2002-027 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article DOI : sans En ligne : https://www.researchgate.net/profile/M-Crosetto/publication/251813611_Optimised_ [...] Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=21944
in Photogrammetric Engineering & Remote Sensing, PERS > vol 68 n° 3 (March 2002) . - pp 225 - 232[article]Uncertainty propagation in wildland fire behaviour modelling / A. Bachmann in International journal of geographical information science IJGIS, vol 16 n° 2 (march 2002)
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Titre : Uncertainty propagation in wildland fire behaviour modelling Type de document : Article/Communication Auteurs : A. Bachmann, Auteur ; B. Allgower, Auteur Année de publication : 2002 Article en page(s) : pp 115 - 127 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] aide à la décision
[Termes IGN] combustible
[Termes IGN] incendie
[Termes IGN] incendie de forêt
[Termes IGN] incertitude géométrique
[Termes IGN] modèle d'incertitude
[Termes IGN] modélisation spatiale
[Termes IGN] risque naturelRésumé : (Auteur) Rothermel's model is the most widely used fire behaviour model in wildland fire research and management. It is a complex model that considers 17 input variables describing fuel type, fuel moisture, terrain and wind. Uncertainties in the input variables can have a substantial impact on the resulting errors and have to be considered, especially when the results are used in spatial decision making. In this paper it is shown that the analysis of uncertainty propagation can be carried out with the Taylor series method. This method is computationally cheaper than Monte Carlo and offers easy-to-use, preliminary sensitivity estimations. Numéro de notice : A2002-023 Affiliation des auteurs : non IGN Thématique : FORET/GEOMATIQUE/INFORMATIQUE Nature : Article DOI : 10.1080/13658810110099080 En ligne : https://doi.org/10.1080/13658810110099080 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=21940
in International journal of geographical information science IJGIS > vol 16 n° 2 (march 2002) . - pp 115 - 127[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-02021 RAB Revue Centre de documentation En réserve L003 Disponible An integrated approach to the Conceptual Data Modeling of an entire highway agency Geographic Information System (GIS) / Hande Demirel (2002)
Titre : An integrated approach to the Conceptual Data Modeling of an entire highway agency Geographic Information System (GIS) Type de document : Thèse/HDR Auteurs : Hande Demirel, Auteur Editeur : Munich : Bayerische Akademie der Wissenschaften Année de publication : 2002 Collection : DGK - C Sous-collection : Dissertationen num. 554 Importance : 107 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-7696-9593-9 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] autoroute
[Termes IGN] cohérence des données
[Termes IGN] généalogie des données
[Termes IGN] modèle conceptuel de données localisées
[Termes IGN] qualité des données
[Termes IGN] réseau routier
[Termes IGN] spécification de contenu
[Termes IGN] système d'information géographiqueRésumé : (Auteur) World-wide highway administrations are stressed to implement new technologies, due to the large amount of information associated with highway networks and the necessity of using sources efficiently in order to realize their tasks. Geographic Information Systems-Transportation (GIS-T), which are specifically tailored for highway administrations, are identified having the highest information technology payoff potential by the highway administrations due to road information spatial character. Contrarily, road information spatial character is not adequately considered during system design, as a result, many of the benefits of GIS-T are not fully realized and efficiency of this technology is mainly under estimated. The relative success of implemented system is not clear without a detailed information analysis and a data model, which rely on formal data model design methodologies. It was determined during this study that several demands of highway administrations were not responded by means of current systems. These topics can be summarized as follows ; firstly, relationships among geometry, topology and thematic information were not structured. The geometry information can not be mapped in various reference systems without redundancy. Thirdly, the non-planar multi-abstraction topological information was not exist. The entire highway administrations business rules can not be performed in the current systems. The existing information and methods were not integrated into the system. The metadata including consistency rules, quality specifications and history information needed to be incorporated into the system. Especially in order to determine permanent, non-spatial and a unique object identifier, regulations and new approaches are required.
In order to increase the efficiency of GIS-T and fullfil these requirements, this study considered a progressive approach appropriate to the conceptual data modeling requirements of an entire highway agency. The main approach of the proposed data model was abstraction and decomposition of geometry, topology and non-spatial data. In order to achieve data integration, control of redundancy and optimization of data maintenance, linear elements were mapped by means of datum invariant parameters. The proposed conceptual data model was successfully implemented using the integrated approach in one object-relational system and results were discussed.Numéro de notice : 13122 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Thèse étrangère Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=54890 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 13122-01 37.10 Livre Centre de documentation Géomatique Disponible L'appariement pour la constitution de bases de données géographiques multi-résolutions / David Sheeren (2002)
PermalinkApport de l'information géographique dans le traitement des incidents ferroviaires / E. Rousseau (2002)
PermalinkPermalinkComparaison des éléments linéaires de deux bases de données géographiques, version 1.2 / Patrick Marmonier (2002)
PermalinkConstruction d'une base de données images pour le référentiel géographique infrastructure de la SNCF / B. Gandelot (2002)
PermalinkContribution à la définition d'une méthodologie d'évaluation de l'évolution du territoire / Chantal Lefebvre (2002)
PermalinkContribution au développement d'une base de données à référence spatiale pour l'aide à la décision dans la lutte contre la désertification / K. Talbi (2002)
PermalinkPermalinkElaboration d'une base de données relatives aux mesures agro-environnementales / K. Joussaume (2002)
PermalinkElaboration et mise en œuvre du contrôle qualité de la base de données du registre parcellaire graphique 2002 / S. Darly (2002)
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