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Popularity-aware collective keyword queries in road networks / Sen Zhao in Geoinformatica, vol 21 n° 3 (July - September 2017)
[article]
Titre : Popularity-aware collective keyword queries in road networks Type de document : Article/Communication Auteurs : Sen Zhao, Auteur ; Xiang Cheng, Auteur ; Sen Su, Auteur ; Kai Shuang, Auteur Année de publication : 2017 Article en page(s) : pp 485 - 518 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géomatique web
[Termes IGN] graphe
[Termes IGN] langage de requête
[Termes IGN] langage naturel (informatique)
[Termes IGN] point d'intérêt
[Termes IGN] positionnement automatique
[Termes IGN] requête (informatique)
[Termes IGN] réseau routierRésumé : (Auteur) This paper addresses a popularity-aware collective keyword (PAC-K) query in road networks. Given a road network with POIs (Points of Interest), which is modeled as a road network graph, where each node locating in a two-dimensional space represents a road intersection or a POI, and each edge with weight represents a road segment, the PACK query aims to find a group of popular POIs (i.e., a popular region) that cover the query’s keywords and satisfy the distance requirements from each node to the query node and between each pair of nodes, such that the sum of rating scores over these nodes for the query keywords is maximized. We show the problem of answering the PACK query is NP-Hard. To solve this problem, we present exact and heuristic solutions on small and large road networks, respectively. In particular, to improve query performance, we propose a rating score scaling technique to reduce the search space and a redundant computation reducing technique to reduce the excessive redundant computations in query processing. Extensive performance studies using two real datasets confirm the efficiency, accuracy, and scalability of the proposed solutions. Numéro de notice : A2017-378 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1007/s10707-017-0299-9 En ligne : https://doi.org/10.1007/s10707-017-0299-9 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=85810
in Geoinformatica > vol 21 n° 3 (July - September 2017) . - pp 485 - 518[article]Extracting urban functional regions from points of interest and human activities on location-based social networks / Song Gao in Transactions in GIS, vol 21 n° 3 (June 2017)
[article]
Titre : Extracting urban functional regions from points of interest and human activities on location-based social networks Type de document : Article/Communication Auteurs : Song Gao, Auteur ; Krzysztof Janowicz, Auteur ; Helen Couclelis, Auteur Année de publication : 2017 Article en page(s) : pp 446 - 467 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] classification par nuées dynamiques
[Termes IGN] connaissance thématique
[Termes IGN] Etats-Unis
[Termes IGN] point d'intérêt
[Termes IGN] problème de Dirichlet
[Termes IGN] réseau social géodépendant
[Termes IGN] trace GPS
[Termes IGN] triangulation de Delaunay
[Termes IGN] zone urbaineRésumé : (Auteur) Data about points of interest (POI) have been widely used in studying urban land use types and for sensing human behavior. However, it is difficult to quantify the correct mix or the spatial relations among different POI types indicative of specific urban functions. In this research, we develop a statistical framework to help discover semantically meaningful topics and functional regions based on the co-occurrence patterns of POI types. The framework applies the latent Dirichlet allocation (LDA) topic modeling technique and incorporates user check-in activities on location-based social networks. Using a large corpus of about 100,000 Foursquare venues and user check-in behavior in the 10 most populated urban areas of the US, we demonstrate the effectiveness of our proposed methodology by identifying distinctive types of latent topics and, further, by extracting urban functional regions using K-means clustering and Delaunay triangulation spatial constraints clustering. We show that a region can support multiple functions but with different probabilities, while the same type of functional region can span multiple geographically non-adjacent locations. Since each region can be modeled as a vector consisting of multinomial topic distributions, similar regions with regard to their thematic topic signatures can be identified. Compared with remote sensing images which mainly uncover the physical landscape of urban environments, our popularity-based POI topic modeling approach can be seen as a complementary social sensing view on urban space based on human activities. Numéro de notice : A2017-623 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/tgis.12289 En ligne : http://dx.doi.org/10.1111/tgis.12289 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=86938
in Transactions in GIS > vol 21 n° 3 (June 2017) . - pp 446 - 467[article]Effectiveness of Natura 2000 network in Romanian Alpine Biogeographical Region: an assessment based on forest landscape connectivity / Mihaita Iulian Niculae in Annals of forest research, vol 60 n° 1 (January - June 2017)
[article]
Titre : Effectiveness of Natura 2000 network in Romanian Alpine Biogeographical Region: an assessment based on forest landscape connectivity Type de document : Article/Communication Auteurs : Mihaita Iulian Niculae, Auteur ; Sorin Avram, Auteur ; Gabriel Ovidiu Vanau, Auteur ; Maria Patroescu, Auteur Année de publication : 2017 Article en page(s) : pp 19 - 32 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] connexité (topologie)
[Termes IGN] corridor biologique
[Termes IGN] forêt tempérée
[Termes IGN] graphe
[Termes IGN] politique de conservation (biodiversité)
[Termes IGN] Roumanie
[Termes IGN] site Natura 2000
[Vedettes matières IGN] Ecologie forestièreRésumé : (auteur) Maintaining and increasing landscape connectivity, especially of forest landscapes, are some of the main concerns regarding biodiversity conservation. The connectivity of protected areas for different species represents an indicator for evaluating the effectiveness of the Natura 2000 network. Our research aims to evaluate the connectivity of forest landscapes in the Romanian Alpine Biogeographical Region (ABR) for various terrestrial species. We analysed the distribution of forest patches and Sites of Community Importance (SCI), as part of Natura 2000 network, in the Romanian ABR. We evaluated the connectivity of forest patches for terrestrial species with different dispersal distances, identifying those patches with significant contribution to maintain the forest landscape connectivity, through the graph theory approach. To quantify the importance of each node, we evaluated the dPCconnector fraction derived from the dPC index. Of the 125 SCIs in the Romanian ABR, 71 protected areas have over 1000 ha, four of them have more than 100,000 ha. The total protected surfaces cover ~35% of the Romanian ABR, and the forest surfaces, protected in SCIs, cover 26% of the total Romanian ABR. Regarding the connectivity scores, we found that the forest surfaces across the ABR are well connected (0.89 or 1 for different dispersal distances) in comparison with the Natura 2000 forest patches. The forest patches are well connected especially for the species with large dispersal distance in both cases (d = 25 km). For the species characterized by a small dispersion distance, the connectivity is lower (0.46) in the case of protected forests. Our results evidence that the connectivity objective of the forest surfaces protected through the Nature 2000 network is not totally achieved. Furthermore new protected areas are needed where the forest are still present for increasing landscape connectivity for species. Numéro de notice : A2017-610 Affiliation des auteurs : non IGN Thématique : BIODIVERSITE/FORET Nature : Article DOI : 10.15287/afr.2016.793 En ligne : http://doi.org/10.15287/afr.2016.793 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=86918
in Annals of forest research > vol 60 n° 1 (January - June 2017) . - pp 19 - 32[article]The analysis and measurement of building patterns using texton co-occurrence matrices / Wenhao Yu in International journal of geographical information science IJGIS, vol 31 n° 5-6 (May-June 2017)
[article]
Titre : The analysis and measurement of building patterns using texton co-occurrence matrices Type de document : Article/Communication Auteurs : Wenhao Yu, Auteur ; Tinghua Ai, Auteur ; Pengcheng Liu, Auteur ; Xiaoqiang Cheng, Auteur Année de publication : 2017 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Photogrammétrie numérique
[Termes IGN] données vectorielles
[Termes IGN] matrice de co-occurrence
[Termes IGN] métrique
[Termes IGN] modèle géométrique du bâti
[Termes IGN] reconnaissance de formes
[Termes IGN] reconstruction 2D du bâti
[Termes IGN] tessellation
[Termes IGN] triangulation de Delaunay
[Termes IGN] voisinage (relation topologique)Résumé : (auteur) The representation and analysis of building patterns are critical for characterizing urban scenes and making decisions in urban planning. The evaluation of building patterns is a difficult spatial analysis problem that exhibits properties of symbolization, homogeneity and regularity. Open issues in this field include the development of approaches for representing building patterns and vector-based methods for computing various pattern metrics. In the image analysis domain, there are many methods for pattern recognition (e.g., texture analysis), but there are few corresponding solutions for vector data. The aim of this research is to develop several building pattern metrics and offer a texton co-occurrence matrix (TCM)-based method to quantitatively evaluate the features of building patterns. The procedure first constructs a spatial field based on a Delaunay triangulation skeleton to partition a set of buildings into a set of tessellation cells. The tessellations of building clusters have a similar structure as image representations, in that each cell corresponds to an image pixel. We then use the texton analysis to establish a matrix to describe the tessellation structure, including the neighboring relationships and individual attribute information. Finally, a set of feature descriptors is obtained from the TCM to capture the texture-related information of building groups. Through experiments on building pattern analysis and spatial queries, we show that the results of TCM-based evaluation of building patterns are consistent with those of human cognition. Numéro de notice : A2017-242 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/13658816.2016.1265121 En ligne : http://dx.doi.org/10.1080/13658816.2016.1265121 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=85178
in International journal of geographical information science IJGIS > vol 31 n° 5-6 (May-June 2017)[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-2017031 RAB Revue Centre de documentation En réserve L003 Disponible Asymptotic behavior of the growth-fragmentation equation with bounded fragmentation rate / Etienne Bernard in Journal of functional analysis, vol 272 n° 8 (15 April 2017)
[article]
Titre : Asymptotic behavior of the growth-fragmentation equation with bounded fragmentation rate Type de document : Article/Communication Auteurs : Etienne Bernard , Auteur ; Pierre Gabriel, Auteur Année de publication : 2017 Projets : KIBORD / Article en page(s) : pp 3455 - 3485 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse numérique
[Termes IGN] analyse fonctionnelle (mathématiques)
[Termes IGN] équation intégrale
[Termes IGN] invariantRésumé : (Auteur) We are interested in the large time behavior of the solutions to the growth-fragmentation equation. We work in the space of integrable functions weighted with the principal dual eigenfunction of the growth-fragmentation operator. This space is the largest one in which we can expect convergence to the steady size distribution. Although this convergence is known to occur under fairly general conditions on the coefficients of the equation, we prove that it does not happen uniformly with respect to the initial data when the fragmentation rate in bounded. First we get the result for fragmentation kernels which do not form arbitrarily small fragments by taking advantage of the Dyson–Phillips series. Then we extend it to general kernels by using the notion of quasi-compactness and the fact that it is a topological invariant. Numéro de notice : A2017-779 Affiliation des auteurs : LASTIG LAREG+Ext (2012-mi2018) Thématique : MATHEMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.jfa.2017.01.009 Date de publication en ligne : 31/01/2017 En ligne : https://doi.org/10.1016/j.jfa.2017.01.009 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=88986
in Journal of functional analysis > vol 272 n° 8 (15 April 2017) . - pp 3455 - 3485[article]Approximation algorithms for visibility computation and testing over a terrain / Sharareh Alipour in Applied geomatics, vol 9 n° 1 (March 2017)PermalinkEfficient edge-aware surface mesh reconstruction for urban scenes / András Bódis-Szomorú in Computer Vision and image understanding, vol 157 (April 2017)PermalinkA spatial anomaly points and regions detection method using multi-constrained graphs and local density / Yan Shi in Transactions in GIS, vol 21 n° 2 (April 2017)PermalinkGeodesic equations and their numerical solutions in geodetic and cartesian coordinates on an oblate spheroid / Georgios Panou in Journal of geodetic science, vol 7 n° 1 (February 2017)PermalinkDonnées 3D et SIG en open source / Anonyme in Géomatique expert, n° 114 (janvier - février 2017)PermalinkEtude et méthodes d'intégration et d'interaction de données 3D complexes type "nuages de points" vers un web SIG / Victor Lambert (2017)PermalinkFusion of graph embedding and sparse representation for feature extraction and classification of hyperspectral imagery / Fulin Luo in Photogrammetric Engineering & Remote Sensing, PERS, vol 83 n° 1 (January 2017)PermalinkHigh-quality seamless DEM generation blending SRTM-1, ASTER GDEM v2 and ICESat/GLAS observations / Linwei Yue in ISPRS Journal of photogrammetry and remote sensing, vol 123 (January 2017)PermalinkPermalinkA taxonomy and survey of dynamic graph visualization / Fabian Beck in Computer graphics forum, vol 36 n° 1 (January 2017)Permalink