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Hyperspectral band selection via optimal neighborhood reconstruction / Qi Wang in IEEE Transactions on geoscience and remote sensing, Vol 58 n° 12 (December 2020)
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Titre : Hyperspectral band selection via optimal neighborhood reconstruction Type de document : Article/Communication Auteurs : Qi Wang, Auteur ; Fahong Zhang, Auteur ; Xuelong Li, Auteur Année de publication : 2020 Article en page(s) : pp 8465 - 8476 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes descripteurs IGN] analyse combinatoire (maths)
[Termes descripteurs IGN] image hyperspectrale
[Termes descripteurs IGN] image multibande
[Termes descripteurs IGN] optimisation (mathématiques)
[Termes descripteurs IGN] reconstruction d'image
[Termes descripteurs IGN] réductionRésumé : (auteur) Band selection is one of the most important technique in the reduction of hyperspectral image (HSI). Different from traditional feature selection problem, an important characteristic of it is that there is usually strong correlation between neighboring bands, that is, bands with close indexes. Aiming to fully exploit this prior information, a novel band selection method called optimal neighborhood reconstruction (ONR) is proposed. In ONR, band selection is considered as a combinatorial optimization problem. It evaluates a band combination by assessing its ability to reconstruct the original data, and applies a noise reducer to minimize the influence of noisy bands. Instead of using some approximate algorithms, ONR exploits a recurrence relation that underlies the optimization target to obtain the optimal solution in an efficient way. Besides, we develop a parameter selection approach to automatically determine the parameter of ONR, ensuring it is adaptable to different data sets. In experiments, ONR is compared with some state-of-the-art methods on six HSI data sets. The results demonstrate that ONR is more effective and robust than the others in most of the cases. Numéro de notice : A2020-742 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2020.2987955 date de publication en ligne : 29/04/2020 En ligne : https://doi.org/10.1109/TGRS.2020.2987955 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96372
in IEEE Transactions on geoscience and remote sensing > Vol 58 n° 12 (December 2020) . - pp 8465 - 8476[article]Mining regional patterns of land use with adaptive adjacent criteria / Xinmeng Tu in Cartography and Geographic Information Science, Vol 47 n° 5 (September 2020)
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Titre : Mining regional patterns of land use with adaptive adjacent criteria Type de document : Article/Communication Auteurs : Xinmeng Tu, Auteur ; Zhenjie Chen, Auteur ; Beibei Wang, Auteur ; changqing Xu, Auteur Année de publication : 2020 Article en page(s) : pp 418 - 431 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes descripteurs IGN] adjacence
[Termes descripteurs IGN] analyse combinatoire (maths)
[Termes descripteurs IGN] analyse de groupement
[Termes descripteurs IGN] analyse spatio-temporelle
[Termes descripteurs IGN] changement d'utilisation du sol
[Termes descripteurs IGN] Chine
[Termes descripteurs IGN] construction
[Termes descripteurs IGN] extraction de modèle
[Termes descripteurs IGN] filtrage spatiotemporel
[Termes descripteurs IGN] occupation du sol
[Termes descripteurs IGN] polygone
[Termes descripteurs IGN] région
[Termes descripteurs IGN] relation spatiale
[Termes descripteurs IGN] surface cultivée
[Termes descripteurs IGN] urbanisation
[Termes descripteurs IGN] utilisation du sol
[Termes descripteurs IGN] variogrammeRésumé : (auteur) Land use/cover changes (LULC) are complicated and regionally diverse. When mining regional patterns, the use of a spatial relationship that is determined without considering the spatial correlation among geographical objects can lead to problematic results, e.g. mistakenly treating unrelated objects as adjacent. Additionally, traditional prevalence measures are unstable for uneven datasets such as LULC, wherein some land-use change types show small numbers and uneven quantities, and valuable rules for some land-use categories may be ignored. Therefore, we proposed a regional pattern mining method. First, we developed adaptive adjacent criteria, which can be automatically generated for each specific zone to define adjacency for better spatial-temporal mining. Then, a combinational decision model was built to improve the stability of the prevalence measure, which was used to filter out the insignificant spatial-temporal rules. Furthermore, we proposed two levels of land-use pattern mining, i.e. cluster-level mining and polygon-level mining, to first discover hot-spot areas where similar land-use change has occurred frequently and then to determine the location, frequency, and change time of rules related to different land-use activities. The proposed method was used for mining the dependence of land use and regional patterns on land-use changes. Results show that the proposed method can determine the spatial dependence between the land-use categories, as well as regional patterns of land-use changes. According to our research, the study area, Xinbei District, China, is undergoing land-use change involving rapid urbanization, extensive transportation construction, and losses of farmland. Numéro de notice : A2020-487 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/URBANISME Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/15230406.2020.1761452 date de publication en ligne : 18/06/2020 En ligne : https://doi.org/10.1080/15230406.2020.1761452 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95655
in Cartography and Geographic Information Science > Vol 47 n° 5 (September 2020) . - pp 418 - 431[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 032-2020051 SL Revue Centre de documentation Revues en salle Disponible Combinatorial optimization applied to VLBI scheduling / A. Corbin in Journal of geodesy, vol 94 n°2 (February 2020)
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Titre : Combinatorial optimization applied to VLBI scheduling Type de document : Article/Communication Auteurs : A. Corbin, Auteur ; B. Niedermann, Auteur ; Axel Nothnagel, Auteur ; et al., Auteur Année de publication : 2020 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes descripteurs IGN] analyse combinatoire (maths)
[Termes descripteurs IGN] données VGOS
[Termes descripteurs IGN] interférométrie à très grande base
[Termes descripteurs IGN] positionnement par ITGB
[Termes descripteurs IGN] programmation linéaire
[Termes descripteurs IGN] retard troposphérique zénithal
[Termes descripteurs IGN] station VLBI
[Termes descripteurs IGN] téléscope
[Termes descripteurs IGN] temps universel coordonnéRésumé : (auteur) Due to the advent of powerful solvers, today linear programming has seen many applications in production and routing. In this publication, we present mixed-integer linear programming as applied to scheduling geodetic very-long-baseline interferometry (VLBI) observations. The approach uses combinatorial optimization and formulates the scheduling task as a mixed-integer linear program. Within this new method, the schedule is considered as an entity containing all possible observations of an observing session at the same time, leading to a global optimum. In our example, the optimum is found by maximizing the sky coverage score. The sky coverage score is computed by a hierarchical partitioning of the local sky above each telescope into a number of cells. Each cell including at least one observation adds a certain gain to the score. The method is computationally expensive and this publication may be ahead of its time for large networks and large numbers of VLBI observations. However, considering that developments of solvers for combinatorial optimization are progressing rapidly and that computers increase in performance, the usefulness of this approach may come up again in some distant future. Nevertheless, readers may be prompted to look into these optimization methods already today seeing that they are available also in the geodetic literature. The validity of the concept and the applicability of the logic are demonstrated by evaluating test schedules for five 1-h, single-baseline Intensive VLBI sessions. Compared to schedules that were produced with the scheduling software sked, the number of observations per session is increased on average by three observations and the simulated precision of UT1-UTC is improved in four out of five cases (6 μs average improvement in quadrature). Moreover, a simplified and thus much faster version of the mixed-integer linear program has been developed for modern VLBI Global Observing System telescopes. Numéro de notice : A2020-153 Affiliation des auteurs : non IGN Thématique : MATHEMATIQUE/POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-020-01348-w date de publication en ligne : 29/01/2020 En ligne : https://doi.org/10.1007/s00190-020-01348-w Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94786
in Journal of geodesy > vol 94 n°2 (February 2020)[article]Spatiotemporal model for assessing the stability of urban human convergence and divergence patterns / Zhixiang Fang in International journal of geographical information science IJGIS, vol 31 n° 11-12 (November - December 2017)
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Titre : Spatiotemporal model for assessing the stability of urban human convergence and divergence patterns Type de document : Article/Communication Auteurs : Zhixiang Fang, Auteur ; Xiping Yang, Auteur ; Yang Xu, Auteur ; et al., Auteur Année de publication : 2017 Article en page(s) : pp 2119 - 2141 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes descripteurs IGN] analyse combinatoire (maths)
[Termes descripteurs IGN] analyse spatio-temporelle
[Termes descripteurs IGN] échelle variable
[Termes descripteurs IGN] géopositionnement
[Termes descripteurs IGN] Kouangtoung (Chine)
[Termes descripteurs IGN] mobilité urbaine
[Termes descripteurs IGN] réseau de transport
[Termes descripteurs IGN] téléphonie mobile
[Termes descripteurs IGN] trace GPS
[Termes descripteurs IGN] transport collectifRésumé : (Auteur) Understanding the stability of urban flows is critical for urban transportation, urban planning and public health. However, few studies have measured the stability of aggregate human convergence or divergence patterns. We propose a spatiotemporal model for assessing the stability of human convergence and divergence patterns. A mobile phone location data set obtained from Shenzhen, China, was used to assess the stability of daily human convergence and divergence patterns at three different spatial scales, i.e. points (cell phone towers), lines (bus lines) and areas (traffic analysis zones [TAZs]). Our analysis results demonstrated that the proposed model can identify points and bus lines with time-dependent variations in stability, which is useful for delineating TAZs for transportation planning, or adjusting bus timetables and routes to meet the needs of bus riders. Comparisons of the results obtained from the proposed model and the widely used entropy measure indicated that the proposed model is suitable for assessing the differences in stability for various types of spatial analysis units, e.g. cell phone towers. Therefore, the proposed model is a useful alternative approach of measuring spatiotemporal stability of aggregate human convergence and divergence patterns, which can be derived from the space–time trajectories of moving objects. Numéro de notice : A2017-698 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/URBANISME Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/13658816.2017.1346256 En ligne : https://doi.org/10.1080/13658816.2017.1346256 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=88079
in International journal of geographical information science IJGIS > vol 31 n° 11-12 (November - December 2017) . - pp 2119 - 2141[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-2017061 RAB Revue Centre de documentation En réserve 3L Disponible 079-2017062 RAB Revue Centre de documentation En réserve 3L Disponible Snapshot and continuous points-based trajectory search / Shuyao Qi in Geoinformatica [en ligne], vol 21 n° 4 (October - December 2017)
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Titre : Snapshot and continuous points-based trajectory search Type de document : Article/Communication Auteurs : Shuyao Qi, Auteur ; Dimitri Sacharidis, Auteur ; Panagiotis Bouros, Auteur ; Nikos Mamoulis, Auteur Année de publication : 2017 Article en page(s) : pp 669 - 701 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes descripteurs IGN] analyse combinatoire (maths)
[Termes descripteurs IGN] calcul d'itinéraire
[Termes descripteurs IGN] distance
[Termes descripteurs IGN] itinéraire voisin le plus proche
[Termes descripteurs IGN] temps
[Termes descripteurs IGN] temps instantané
[Termes descripteurs IGN] théorie des possibilitésRésumé : (Auteur) Trajectory data capture the traveling history of moving objects such as people or vehicles. With the proliferation of GPS and tracking technologies, huge volumes of trajectories are rapidly generated and collected. Under this, applications such as route recommendation and traveling behavior mining call for efficient trajectory retrieval. In this paper, we first focus on distance-to-points trajectory search; given a collection of trajectories and a set query points, the goal is to retrieve the top-k trajectories that pass as close as possible to all query points. We advance the state-of-the-art by combining existing approaches to a hybrid nearest neighbor-based method while also proposing an alternative, more efficient spatial range-based approach. Second, we investigate the continuous counterpart of distance-to-points trajectory search where the query is long-standing and the set of returned trajectories needs to be maintained whenever updates occur to the query and/or the data. Third, we propose and study two practical variants of distance-to-points trajectory search, which take into account the temporal characteristics of the searched trajectories. Through an extensive experimental analysis with real trajectory data, we show that our range-based approach outperforms previous methods by at least one order of magnitude for the snapshot and up to several times for the continuous version of the queries. Numéro de notice : A2017-600 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1007/s10707-016-0267-9 En ligne : https://doi.org/10.1007/s10707-016-0267-9 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=86908
in Geoinformatica [en ligne] > vol 21 n° 4 (October - December 2017) . - pp 669 - 701[article]BIM : New perspectives / Nigel Alexander in GEO: Geoconnexion international, vol 16 n° 3 (March 2017)
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PermalinkGeographically weighted evidence combination approaches for combining discordant and inconsistent volunteered geographical information / Alexis Comber in Geoinformatica [en ligne], vol 20 n° 3 (July - September 2016)
PermalinkToward a generalizable image representation for large-scale change detection : application to generic damage analysis / Lionel Gueguen in IEEE Transactions on geoscience and remote sensing, vol 54 n° 6 (June 2016)
PermalinkAn enhanced algorithm to estimate BDS satellite’s differential code biases / Chuang Shi in Journal of geodesy, vol 90 n° 2 (February 2016)
PermalinkCombining spaceborne SAR images with 3D point clouds for infrastructure monitoring applications / Andrei Anghel in ISPRS Journal of photogrammetry and remote sensing, vol 111 (January 2016)
PermalinkSimplifying photogrammetric analysis for assessment of large mammal mass : automated targeting and 3D model building / L. Catherine Bester in Photogrammetric record, vol 30 n° 150 (June - August 2015)
PermalinkMéthode de factorisation progressive pour accroître l’abstraction d’un modèle de classes / André Miralles in Ingénierie des systèmes d'information, ISI : Revue des sciences et technologies de l'information, RSTI, vol 20 n° 2 (mars - avril 2015)
PermalinkCalibration of area based diameter distribution with individual tree based diameter estimates using airborne laser scanning / Qing Xu in ISPRS Journal of photogrammetry and remote sensing, vol 93 (July 2014)
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