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Modeling vague spatial data warehouses using the VSCube conceptual model / Thiago Luís Lopes-Siqueira in Geoinformatica, vol 18 n° 2 (April 2014)  

Public [article]  inGeoinformatica > vol 18 n° 2 (April 2014) . - pp 313 - 356 Titre : Modeling vague spatial data warehouses using the VSCube conceptual model Type de document : Article/Communication Auteurs : Thiago Luís Lopes-Siqueira, Auteur ; Cristina Dutra de Aguiar Ciferri, Auteur ; Valéria Cesário Times, Auteur ; Ricardo Rodrigues Ciferre, Auteur Année de publication : 2014 Article en page(s) : pp 313 - 356 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées [Termes IGN] analyse spatiale [Termes IGN] entrepôt de données localisées [Termes IGN] incertitude des données [Termes IGN] modèle conceptuel de données [Termes IGN] objet flou [Termes IGN] SOLAP Résumé : (Auteur) Although many real world phenomena are vague and characterized by having uncertain location or vague shape, existing spatial data warehouse models do not support spatial vagueness and then cannot properly represent these phenomena. In this paper, we propose the VSCube conceptual model to represent and manipulate shape vagueness in spatial data warehouses, allowing the analysis of business scores related to vague spatial data, and therefore improving the decision-making process. Our VSCube conceptual model is based on the cube metaphor and supports geometric shapes and the corresponding membership values, thus providing more expressiveness to represent vague spatial data. We also define vague spatial aggregation functions (e.g. vague spatial union) and vague spatial predicates to enable vague SOLAP queries (e.g. intersection range queries). Finally, we introduce the concept of vague SOLAP and its operations (e.g. drill-down and roll-up). We demonstrate the applicability of our model by describing an application concerning pest control in agriculture and by discussing the reuse of existing models in the VSCube conceptual model. Numéro de notice : A2014-228 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article DOI : 10.1007/s10707-013-0186-y Date de publication en ligne : 12/01/2014 En ligne : https://doi.org/10.1007/s10707-013-0186-y Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=33131 [article]

Exemplaires(1)

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057-2014021	RAB	Revue	Centre de documentation	En réserve L003	Disponible

The SB-index and the HSB-index: efficient indices for spatial data warehouses / Thiago Luís Lopes Siqueira in Geoinformatica, vol 16 n° 1 (January 2012)  

Public [article]  inGeoinformatica > vol 16 n° 1 (January 2012) . - pp 165 - 205 Titre : The SB-index and the HSB-index: efficient indices for spatial data warehouses Type de document : Article/Communication Auteurs : Thiago Luís Lopes Siqueira, Auteur ; Cristina Dutra de Aguiar Ciferri, Auteur ; Valéria Cesário Times, Auteur ; Ricardo Rodrigues Ciferri, Auteur Année de publication : 2012 Article en page(s) : pp 165 - 205 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Infrastructure de données [Termes IGN] entrepôt de données localisées [Termes IGN] format BITMAP [Termes IGN] index spatial [Termes IGN] indexation spatiale [Termes IGN] SOLAP Résumé : (Auteur) Spatial data warehouses (SDWs) allow for spatial analysis together with analytical multidimensional queries over huge volumes of data. The challenge is to retrieve data related to ad hoc spatial query windows according to spatial predicates, avoiding the high cost of joining large tables. Therefore, mechanisms to provide efficient query processing over SDWs are essential. In this paper, we propose two efficient indices for SDW: the SB-index and the HSB-index. The proposed indices share the following characteristics. They enable multidimensional queries with spatial predicate for SDW and also support predefined spatial hierarchies. Furthermore, they compute the spatial predicate and transform it into a conventional one, which can be evaluated together with other conventional predicates by accessing a star-join Bitmap index. While the SB-index has a sequential data structure, the HSB-index uses a hierarchical data structure to enable spatial objects clustering and a specialized buffer-pool to decrease the number of disk accesses. The advantages of the SB-index and the HSB-index over the DBMS resources for SDW indexing (i.e. star-join computation and materialized views) were investigated through performance tests, which issued roll-up operations extended with containment and intersection range queries. The performance results showed that improvements ranged from 68% up to 99% over both the star-join computation and the materialized view. Furthermore, the proposed indices proved to be very compact, adding only less than 1% to the storage requirements. Therefore, both the SB-index and the HSB-index are excellent choices for SDW indexing. Choosing between the SB-index and the HSB-index mainly depends on the query selectivity of spatial predicates. While low query selectivity benefits the HSB-index, the SB-index provides better performance for higher query selectivity. Numéro de notice : A2012-085 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1007/s10707-011-0128-5 Date de publication en ligne : 14/06/2011 En ligne : https://doi.org/10.1007/s10707-011-0128-5 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=31533 [article]

Exemplaires(1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
057-2012011	RAB	Revue	Centre de documentation	En réserve L003	Disponible