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GMOBench: Benchmarking generic moving objects / Jianqiu Xu in Geoinformatica, vol 19 n° 2 (April - June 2015)
[article]
Titre : GMOBench: Benchmarking generic moving objects Type de document : Article/Communication Auteurs : Jianqiu Xu, Auteur ; Ralf Hartmut Güting, Auteur ; Xiaolin Qin, Auteur Année de publication : 2015 Article en page(s) : pp 227 - 276 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géomatique
[Termes IGN] arbre-R
[Termes IGN] base de données orientée objet
[Termes IGN] implémentation (informatique)
[Termes IGN] index spatial
[Termes IGN] mobilité humaine
[Termes IGN] mobilité urbaine
[Termes IGN] objet mobile
[Termes IGN] point de repère
[Termes IGN] requête spatiale
[Termes IGN] test de performanceRésumé : (auteur) In real world scenarios, people’s movement include several environments rather than one, for example, road network, pavement areas and indoor. This imposes a new challenge for moving objects database that the complete trip needs to be managed by a database system. In the meantime, novel queries regarding different transportation modes should also be supported. Since existing methods are limited to trips in a single environment and do not support queries on moving objects with different transportation modes, new technologies are essentially needed in a database system. In this paper, we introduce a benchmark called GMOBench that aims to evaluate the performance of a database system managing moving objects in different environments. GMOBench is settled in a realistic scenario and is comprised of three components: (1) a data generator with the capability of creating a scalable set of trips representing the complete movement of humans (both indoor and outdoor); (2) a set of carefully designed and benchmark queries; (3) Mode-RTree, an index structure for managing generic moving objects. The generator defines some parameters so that users can control the characteristics of results. We create the benchmark data in such a way that the dataset can mirror important characteristics and real world distributions of human mobility. Efficient access methods and optimization techniques are developed for query processing. In particular, we propose an index structure called Mode-RTree to manage moving objects in different environments. By employing the proposed index, the cost of benchmark queries is greatly reduced. GMOBench is implemented in a real database system to have a practical result. We perform an extensive experimental study on comprehensive datasets to evaluate the performance. The results show that by using the Mode-RTree we achieve significant performance improvement over the baseline method, demonstrating the effectiveness and efficiency of our approaches. Numéro de notice : A2015-488 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1007/s10707-014-0211-9 Date de publication en ligne : 26/06/2014 En ligne : https://doi.org/10.1007/s10707-014-0211-9 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=77281
in Geoinformatica > vol 19 n° 2 (April - June 2015) . - pp 227 - 276[article]The largest empty rectangle containing only a query object in Spatial Databases / Gilberto Gutiérrez in Geoinformatica, vol 18 n° 2 (April 2014)
[article]
Titre : The largest empty rectangle containing only a query object in Spatial Databases Type de document : Article/Communication Auteurs : Gilberto Gutiérrez, Auteur ; José R. Paramá, Auteur ; Nieves Brisaboa, Auteur ; Antonio Corral, Auteur Année de publication : 2014 Article en page(s) : pp 193 - 228 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] arbre-R
[Termes IGN] base de données localisées
[Termes IGN] classification automatique d'objets
[Termes IGN] indexation spatiale
[Termes IGN] requête spatiale
[Termes IGN] traitement automatique de donnéesRésumé : (Auteur) Let S be a set of n points in a fixed axis-parallel rectangle R Í R2 , i.e. in the two-dimensional space (2D). Assuming that those points are stored in an R-tree, this paper presents several algorithms for finding the empty rectangle in R with the largest area, sides parallel to the axes of the space, and containing only a query point q. This point can not be part of S, that is, it is not stored in the R-tree. All algorithms follow the basic idea of discarding part of the points of S, in such a way that the problem can be solved only considering the remaining points. As a consequence, the algorithms only have to access a very small portion of the nodes (disk blocks) of the R-tree, saving main memory resources and computation time. We provide formal proofs of the correctness of our algorithms and, in order to evaluate the performance of the algorithms, we run an extensive set of experiments using synthetic and real data. The results have demonstrated the efficiency and scalability of our algorithms for different dataset configurations. Numéro de notice : A2014-224 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article DOI : 10.1007/s10707-013-0178-y Date de publication en ligne : 19/04/2013 En ligne : https://doi.org/10.1007/s10707-013-0178-y Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=33127
in Geoinformatica > vol 18 n° 2 (April 2014) . - pp 193 - 228[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 057-2014021 RAB Revue Centre de documentation En réserve L003 Disponible The k closest pairs in spatial databases: When only set is indexed / Gilberto Gutiérrez in Geoinformatica, vol 17 n° 4 (October 2013)
[article]
Titre : The k closest pairs in spatial databases: When only set is indexed Type de document : Article/Communication Auteurs : Gilberto Gutiérrez, Auteur ; Pablo Saez, Auteur Année de publication : 2013 Article en page(s) : pp 543 - 565 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] arbre-R
[Termes IGN] base de données localisées
[Termes IGN] extensibilité
[Termes IGN] rectangle englobant minimum
[Termes IGN] requête spatialeRésumé : (Auteur) We provide in this article a branch-and-bound algorithm that solves the problem of finding the k closest pairs of points (p,q), p € P,q € Q, considering two sets of points in the euclidean plane P,Q stored in external memory assuming that only one of the sets has a spatial index. This problem arises naturally in many scenarios, for instance when the set without an index is the answer to a spatial query. The main idea of our algorithm is to partition the space occupied by the set without an index into several cells or subspaces and to make use of the properties of a set of metrics defined on two Minimum Bounding Rectangles (MBRs). We evaluated our algorithm for different values of k by means of a series of experiments that considered both synthetical and real world datasets. We compared the performance of our algorithm with that of techniques that either assume that both datasets have a spatial index or that none has an index. The results show that our algorithm needs only between a 0.3 and a 35 % of the disk accesses required by such techniques. Our algorithm also shows a good scalability, both in terms of k and of the size of the data set. Numéro de notice : A2013-509 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article DOI : 10.1007/s10707-012-0169-4 Date de publication en ligne : 14/09/2012 En ligne : https://doi.org/10.1007/s10707-012-0169-4 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32647
in Geoinformatica > vol 17 n° 4 (October 2013) . - pp 543 - 565[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 057-2013041 RAB Revue Centre de documentation En réserve L003 Disponible Generic and efficient framework for search trees on flash memory storage systems / Mohamed Sarwat in Geoinformatica, vol 17 n° 3 (July 2013)
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Titre : Generic and efficient framework for search trees on flash memory storage systems Type de document : Article/Communication Auteurs : Mohamed Sarwat, Auteur ; Mohamed F. Mokbel, Auteur ; Xun Zhou, Auteur ; Suman Nath, Auteur Année de publication : 2013 Article en page(s) : pp 489 - 519 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Informatique
[Termes IGN] arbre (mathématique)
[Termes IGN] arbre-R
[Termes IGN] indexation spatiale
[Termes IGN] mémoire d'ordinateur
[Termes IGN] mémoire flashRésumé : (Auteur) Tree index structures are crucial components in data management systems. Existing tree index structure are designed with the implicit assumption that the underlying external memory storage is the conventional magnetic hard disk drives. This assumption is going to be invalid soon, as flash memory storage is increasingly adopted as the main storage media in mobile devices, digital cameras, embedded sensors, and notebooks. Though it is direct and simple to port existing tree index structures on the flash memory storage, that direct approach does not consider the unique characteristics of flash memory, i.e., slow write operations, and erase-before-update property, which would result in a sub optimal performance. In this paper, we introduce FAST (i.e., Flash-Aware Search Trees) as a generic framework for flash-aware tree index structures. FAST distinguishes itself from all previous attempts of flash memory indexing in two aspects: (1) FAST is a generic framework that can be applied to a wide class of data partitioning tree structures including R-tree and its variants, and (2) FAST achieves both efficiency and durability of read and write flash operations through memory flushing and crash recovery techniques. Extensive experimental results, based on an actual implementation of FAST inside the GiST index structure in PostgreSQL, show that FAST achieves better performance than its competitors. Numéro de notice : A2013-381 Affiliation des auteurs : non IGN Thématique : INFORMATIQUE Nature : Article DOI : 10.1007/s10707-012-0164-9 Date de publication en ligne : 30/08/2012 En ligne : https://doi.org/10.1007/s10707-012-0164-9 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32519
in Geoinformatica > vol 17 n° 3 (July 2013) . - pp 489 - 519[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 057-2013031 RAB Revue Centre de documentation En réserve L003 Disponible Multi-level representation of terrain features on a contour map / Eric Guilbert in Geoinformatica, vol 17 n° 2 (April 2013)
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Titre : Multi-level representation of terrain features on a contour map Type de document : Article/Communication Auteurs : Eric Guilbert, Auteur Année de publication : 2013 Article en page(s) : pp 301 - 324 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] adjacence
[Termes IGN] arbre (mathématique)
[Termes IGN] carte isoplèthe
[Termes IGN] contour
[Termes IGN] description multiniveau
[Termes IGN] détail topographique
[Termes IGN] généralisation automatique de données
[Termes IGN] représentation multipleRésumé : (Auteur) Contour lines are important for quantitatively displaying relief and identifying morphometric features on a map. Contour trees are often used to represent spatial relationships between contours and assist the user in analysing the terrain. However, automatic analysis from the contour tree is still limited as features identified on a map by sets of contours are not only characterised by local relationships between contours but also by relationships with other features at different levels of representation. In this paper, a new method based on adjacency and inclusion relationships between regions defined by sets of contours is presented. The method extracts terrain features and stores them in a feature tree providing a description of the landscape at multiple levels of detail. The method is applied to terrain analysis and generalisation of a contour map by selecting the most relevant features according to the purpose of the map. Experimental results are presented and discussed. Numéro de notice : A2013-161 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article DOI : 10.1007/s10707-012-0153-z Date de publication en ligne : 11/04/2012 En ligne : https://doi.org/10.1007/s10707-012-0153-z Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32299
in Geoinformatica > vol 17 n° 2 (April 2013) . - pp 301 - 324[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 057-2013021 RAB Revue Centre de documentation En réserve L003 Disponible Parallel indexing technique for spatio-temporal data / Zhenwen He in ISPRS Journal of photogrammetry and remote sensing, vol 78 (April 2013)PermalinkSegmentation hyperspectrale de forêts tropicales par arbres de partition binaires / Guillaume Tochon in Revue Française de Photogrammétrie et de Télédétection, n° 202 (Avril 2013)PermalinkAlgorithmique / Sébastien Rohaut (2013)PermalinkAn efficient point cloud management method based on a 3D R-tree / J. Gong in Photogrammetric Engineering & Remote Sensing, PERS, vol 78 n° 4 (April 2012)PermalinkAn interactive framework for spatial joins : a statistical approach to data analysis in GIS / S. Alkobaisi in Geoinformatica, vol 16 n° 2 (April 2012)PermalinkTree topology representation from TLS point clouds using depth-first search in voxel space / A. Schilling in Photogrammetric Engineering & Remote Sensing, PERS, vol 78 n° 4 (April 2012)PermalinkFiltering and segmentation of polarimetric SAR data based on binary partition trees / A. Alonso-Gonzalez in IEEE Transactions on geoscience and remote sensing, vol 50 n° 2 (February 2012)PermalinkAlgorithms for constrained k-nearest neighbor queries over moving object trajectories / Yunjun Gao in Geoinformatica, vol 14 n° 2 (April 2010)PermalinkUpdate-efficient indexing of moving objects in road networks / J. Chen in Geoinformatica, vol 13 n° 4 (December 2009)PermalinkAlgorithmique / Sébastien Rohaut (2009)Permalink