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Query rewriting for semantic query optimization in spatial databases / Eduardo Mella in Geoinformatica, vol 23 n° 1 (January 2019)  

Public [article]  inGeoinformatica > vol 23 n° 1 (January 2019) . - pp 79 - 104 Titre : Query rewriting for semantic query optimization in spatial databases Type de document : Article/Communication Auteurs : Eduardo Mella, Auteur ; M. Andrea Rodríguez, Auteur ; Loreto Bravo, Auteur ; Diego Gatica, Auteur Année de publication : 2019 Article en page(s) : pp 79 - 104 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées [Termes IGN] contrainte d'intégrité [Termes IGN] jointure spatiale [Termes IGN] optimisation (mathématiques) [Termes IGN] programmation par contraintes [Termes IGN] relation topologique [Termes IGN] requête (informatique) [Termes IGN] requête spatiale [Termes IGN] système de gestion de bases de données orientées objet Résumé : (auteur) Query processing is an important challenge for spatial databases due to the use of complex data types that represent spatial attributes. In particular, due to the cost of spatial joins, several optimization algorithms based on indexing structures exist. The work in this paper proposes a strategy for semantic query optimization of spatial join queries. The strategy detects queries with empty results and rewrites queries to eliminate unnecessary spatial joins or to replace spatial by thematic joins. This is done automatically by analyzing the semantics imposed by the database schema through topological dependencies and topological referential integrity constraints. In this way, the strategy comes to complement current state-of-art algorithms for processing spatial join queries. The experimental evaluation with real data sets shows that the optimization strategy can achieve a decrease in the time cost of a join query using indexing structures in a spatial database management system (SDBMS). Numéro de notice : A2019-224 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s10707-018-00335-w Date de publication en ligne : 04/01/2019 En ligne : http://dx.doi.org/10.1007/s10707-018-00335-w Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92623 [article]

Rank-based strategies for cleaning inconsistent spatial databases / Nieves R. Brisaboa in International journal of geographical information science IJGIS, vol 29 n° 2 (February 2015)  

Public [article]  inInternational journal of geographical information science IJGIS > vol 29 n° 2 (February 2015) . - pp 280 - 304 Titre : Rank-based strategies for cleaning inconsistent spatial databases Type de document : Article/Communication Auteurs : Nieves R. Brisaboa, Auteur ; M. Andrea Rodríguez, Auteur ; Diego Seco, Auteur Année de publication : 2015 Article en page(s) : pp 280 - 304 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées [Termes IGN] cohérence des données [Termes IGN] contrainte d'intégrité [Termes IGN] données massives [Termes IGN] efficacité [Termes IGN] intégrité topologique [Termes IGN] qualité des données [Termes IGN] relation topologique [Termes IGN] révision des données Résumé : (Auteur) A spatial data set is consistent if it satisfies a set of integrity constraints. Although consistency is a desirable property of databases, enforcing the satisfaction of integrity constraints might not be always feasible. In such cases, the presence of inconsistent data may have a negative effect on the results of data analysis and processing and, in consequence, there is an important need for data-cleaning tools to detect and remove, if possible, inconsistencies in large data sets. This work proposes strategies to support data cleaning of spatial databases with respect to a set of integrity constraints that impose topological relations between spatial objects. The basic idea is to rank the geometries in a spatial data set that should be modified to improve the quality of the data (in terms of consistency). An experimental evaluation validates the proposal and shows that the order in which geometries are modified affects both the overall quality of the database and the final number of geometries to be processed to restore consistency. Numéro de notice : A2015-580 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/13658816.2014.965711 En ligne : http://www.tandfonline.com/doi/full/10.1080/13658816.2014.965711 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=77842 [article]

Comparing geospatial entity classes: an asymmetric and context-dependent similarity measure / M. Andrea Rodríguez in International journal of geographical information science IJGIS, vol 18 n° 3 (april - may 2004)  

Public [article]  inInternational journal of geographical information science IJGIS > vol 18 n° 3 (april - may 2004) . - pp 229 - 256 Titre : Comparing geospatial entity classes: an asymmetric and context-dependent similarity measure Type de document : Article/Communication Auteurs : M. Andrea Rodríguez, Auteur ; Max J. Egenhofer, Auteur Année de publication : 2004 Article en page(s) : pp 229 - 256 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées [Termes IGN] analyse comparative [Termes IGN] appariement géométrique [Termes IGN] classe d'objets [Termes IGN] distance [Termes IGN] données hétérogènes [Termes IGN] généralisation automatique de données [Termes IGN] identification automatique [Termes IGN] prise en compte du contexte [Termes IGN] recherche d'information géographique [Termes IGN] similitude sémantique [Termes IGN] système d'information géographique Résumé : (Auteur) Semantic similarity plays an important role in geographic information systems as it supports the identification of objects that are conceptually close, but not identical. Similarity assessments are particularly important for retrieval of geospatial data in such settings as digital libraries, heterogeneous databases, and the World Wide Web. Although some computational models for semantic similarity assessment exist, these models are typically limited by their inability to handle such important cognitive properties of similarity judgements as their inherent asymmetry and their dependence on context. This paper defines the Matching-Distance Similarity Measure (MDSM) for determining semantic similarity among spatial entity classes, taking into account the distinguishing features of these classes (parts, functions, and attributes) and their semantic interrelations (is-a and part-whole relations). A matching process is combined with a semantic-distance calculation to obtain asymmetric values of similarity that depend on the degree of generalization of entity classes. MDSM's matching process is also driven by contextual considerations, where the context determines the relative importance of distinguishing features. Based on a human-subject experiment, MDSM results correlate well with people's judgements of similarity. When contextual information is used for determining the importance of distinguishing features, this correlation increases; however, the major component of the correlation between MDSM results and people's judgements is due to a detailed definition of entity classes. Numéro de notice : A2004-159 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article DOI : 10.1080/13658810310001629592 En ligne : https://doi.org/10.1080/13658810310001629592 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26686 [article]

Exemplaires(2)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
079-04031	RAB	Revue	Centre de documentation	En réserve L003	Disponible
079-04032	RAB	Revue	Centre de documentation	En réserve L003	Disponible

From geo- to eco-ontologies / Frederico Fonseca (2002)

Public contenu dans Geographic information science, Giscience 2002 / Max J. Egenhofer (2002)   Titre : From geo- to eco-ontologies Type de document : Article/Communication Auteurs : Frederico Fonseca, Auteur ; James Martin, Auteur ; M. Andrea Rodríguez, Auteur Editeur : Berlin, Heidelberg, Vienne, New York, ... : Springer Année de publication : 2002 Collection : Lecture notes in Computer Science, ISSN 0302-9743 num. 2478 Conférence : GIScience 2002, 2nd International Conference on geographic information science 25/09/2002 28/09/2002 Boulder Colorado - Etats-Unis Proceedings Springer Importance : pp 93 - 107 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Infrastructure de données [Termes IGN] écologie [Termes IGN] ontologie [Termes IGN] système d'information géographique Résumé : (Auteur) Ecology is a subject of great debate today among scientists, governments, and the general public. Issues such as global warming and biodiversity require a mutual agreement among different groups of people. Many times these groups are separated by language, political interests, and culture. Environmental Information Systems need to integrate data from different Geographic Information Systems. This may cause problems resulting from the semantic heterogeneity of the source communities. Before this kind of integration can happen among different groups, the concepts that people have about the real world must be explicitly formalized ; such an explicit formalization of our mental models is called an ontology. In this paper, we discuss two options for structuring such ontologies. First we discuss the use of hierarchies and roles in the structure of geographic ontologies. Second, we discuss some of the fundamental characteristics of ecological ontologies and draw attention to several formal differences between ecological and geographic ontologies. We conclude by identifying some of the important questions that arise in light of our conception of eco-ontologies. Numéro de notice : C2002-012 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Communication Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=64970