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Continuous aggregate nearest neighbor queries / H. Elmongui in Geoinformatica, vol 17 n° 1 (January 2013)  

Public [article]  inGeoinformatica > vol 17 n° 1 (January 2013) . - pp 63 - 95 Titre : Continuous aggregate nearest neighbor queries Type de document : Article/Communication Auteurs : H. Elmongui, Auteur ; M. Mokbel, Auteur ; W. Aref, Auteur Année de publication : 2013 Article en page(s) : pp 63 - 95 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes d'information géographique [Termes IGN] agrégation spatiale [Termes IGN] données spatiotemporelles [Termes IGN] flux de données [Termes IGN] objet mobile [Termes IGN] plus proche voisin, algorithme du [Termes IGN] requête continue [Termes IGN] requête spatiotemporelle Résumé : (Auteur) This paper addresses the problem of continuous aggregate nearest-neighbor (CANN) queries for moving objects in spatio-temporal data stream management systems. A CANN query specifies a set of landmarks, an integer k, and an aggregate distance function f (e.g., min, max, or sum), where f computes the aggregate distance between a moving object and each of the landmarks. The answer to this continuous query is the set of k moving objects that have the smallest aggregate distance f. A CANN query may also be viewed as a combined set of nearest neighbor queries. We introduce several algorithms to continuously and incrementally answer CANN queries. Extensive experimentation shows that the proposed operators outperform the state-of-the-art algorithms by up to a factor of 3 and incur low memory overhead. Numéro de notice : A2013-047 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article DOI : 10.1007/s10707-011-0149-0 En ligne : https://doi.org/10.1007/s10707-011-0149-0 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32185 [article]

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Efficient evaluation of continuous spatio-temporal queries on moving objects whith uncertain velocity / Y. Huang in Geoinformatica, vol 14 n° 2 (April 2010)  

Public [article]  inGeoinformatica > vol 14 n° 2 (April 2010) . - pp 163 - 200 Titre : Efficient evaluation of continuous spatio-temporal queries on moving objects whith uncertain velocity Type de document : Article/Communication Auteurs : Y. Huang, Auteur ; C. Lee, Auteur Année de publication : 2010 Article en page(s) : pp 163 - 200 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées [Termes IGN] classification barycentrique [Termes IGN] distance euclidienne [Termes IGN] objet mobile [Termes IGN] requête continue [Termes IGN] requête spatiotemporelle [Termes IGN] vitesse Résumé : (Auteur) Continuous Range (CR) query and Continuous K-Nearest Neighbor (CKNN) query are two important types of spatio-temporal queries. Given a time interval [ts , te ] and a moving query object q, a CR query is to find the moving objects whose Euclidean distances to q are within a user-given distance at each time instant within [ts , te ]. A CKNN query is to retrieve the K-Nearest Neighbors (KNNs) of this query object q at each time instant within [ts , te ]. In this paper, we investigate how to process these spatio-temporal queries efficiently under the situation that the velocity of each object is not fixed. This uncertainty on the velocity of object inevitably results in high complexity in processing spatio-temporal queries. We will discuss the complications incurred by this uncertainty and propose two algorithms, namely the Possibility-based possible within objects searching algorithm and the Possibility-based possible KNN searching algorithm, for the CR query and the CKNN query, respectively. A Possibility-based model is designed accordingly to quantify the possibility of each object being the result of a CR query or a CKNN query. Comprehensive experiments are performed to demonstrate the effectiveness and the efficiency of the proposed approaches. Copyright Springer Numéro de notice : A2010-064 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article DOI : 10.1007/s10707-009-0081-8 Date de publication en ligne : 23/04/2009 En ligne : https://doi.org/10.1007/s10707-009-0081-8 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30260 [article]

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Code-barres	Cote	Support	Localisation	Section	Disponibilité
057-2010021	RAB	Revue	Centre de documentation	En réserve L003	Disponible