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Estimating the intrinsic dimension of hyperspectral images using a noise-whitened eigengap approach / Abderrahim Halimi in IEEE Transactions on geoscience and remote sensing, vol 54 n° 7 (July 2016)
[article]
Titre : Estimating the intrinsic dimension of hyperspectral images using a noise-whitened eigengap approach Type de document : Article/Communication Auteurs : Abderrahim Halimi, Auteur ; Paul Honeine, Auteur ; Malika Kharouf, Auteur ; Cédric Richard, Auteur ; Jean-Yves Tourneret, Auteur Année de publication : 2016 Article en page(s) : pp 3811 - 3821 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] bruit blanc
[Termes IGN] image hyperspectrale
[Termes IGN] modèle de mélange multilinéaire
[Termes IGN] valeur propreRésumé : (Auteur) Linear mixture models are commonly used to represent a hyperspectral data cube as linear combinations of endmember spectra. However, determining the number of endmembers for images embedded in noise is a crucial task. This paper proposes a fully automatic approach for estimating the number of endmembers in hyperspectral images. The estimation is based on recent results of random matrix theory related to the so-called spiked population model. More precisely, we study the gap between successive eigenvalues of the sample covariance matrix constructed from high-dimensional noisy samples. The resulting estimation strategy is fully automatic and robust to correlated noise owing to the consideration of a noise-whitening step. This strategy is validated on both synthetic and real images. The experimental results are very promising and show the accuracy of this algorithm with respect to state-of-the-art algorithms. Numéro de notice : A2016-873 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2016.2528298 En ligne : http://dx.doi.org/10.1109/TGRS.2016.2528298 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83032
in IEEE Transactions on geoscience and remote sensing > vol 54 n° 7 (July 2016) . - pp 3811 - 3821[article]Geographically weighted evidence combination approaches for combining discordant and inconsistent volunteered geographical information / Alexis Comber in Geoinformatica, vol 20 n° 3 (July - September 2016)
[article]
Titre : Geographically weighted evidence combination approaches for combining discordant and inconsistent volunteered geographical information Type de document : Article/Communication Auteurs : Alexis Comber, Auteur ; Cidália Costa Fonte, Auteur ; Giles M. Foody, Auteur ; Ana-Maria Olteanu-Raimond , Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 503 – 527 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géomatique web
[Termes IGN] analyse combinatoire (maths)
[Termes IGN] classification bayesienne
[Termes IGN] classification de Dempster-Shafer
[Termes IGN] classification floue
[Termes IGN] données localisées des bénévoles
[Termes IGN] données multisources
[Termes IGN] incertitude des données
[Termes IGN] occupation du sol
[Termes IGN] pondération
[Termes IGN] qualité des données
[Termes IGN] régression géographiquement pondérée
[Termes IGN] WikimapiaRésumé : (auteur) There is much interest in being able to combine crowdsourced data. One of the critical issues in information sciences is how to combine data or information that are discordant or inconsistent in some way. Many previous approaches have taken a majority rules approach under the assumption that most people are correct most of the time. This paper analyses crowdsourced land cover data generated by the Geo-Wiki initiative in order to infer the land cover present at locations on a 50 km grid. It compares four evidence combination approaches (Dempster-Shafer, Bayes, Fuzzy Sets and Possibility) applied under a geographically weighted kernel with the geographically weighted average approach applied in many current Geo-Wiki analyses. A geographically weighted approach uses a moving kernel under which local analyses are undertaken. The contribution (or salience) of each data point to the analysis is weighted by its distance to the kernel centre, reflecting Tobler’s 1st law of geography. A series of analyses were undertaken using different kernel sizes (or bandwidths). Each of the geographically weighted evidence combination methods generated spatially distributed measures of belief in hypotheses associated with the presence of individual land cover classes at each location on the grid. These were compared with GlobCover, a global land cover product. The results from the geographically weighted average approach in general had higher correspondence with the reference data and this increased with bandwidth. However, for some classes other evidence combination approaches had higher correspondences possibly because of greater ambiguity over class conceptualisations and / or lower densities of crowdsourced data. The outputs also allowed the beliefs in each class to be mapped. The differences in the soft and the crisp maps are clearly associated with the logics of each evidence combination approach and of course the different questions that they ask of the data. The results show that discordant data can be combined (rather than being removed from analysis) and that data integrated in this way can be parameterised by different measures of belief uncertainty. The discussion highlights a number of critical areas for future research. Numéro de notice : A2016-379 Affiliation des auteurs : LASTIG COGIT+Ext (2012-2019) Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s10707-016-0248-z Date de publication en ligne : 27/02/2016 En ligne : http://dx.doi.org/ 10.1007/s10707-016-0248-z Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81146
in Geoinformatica > vol 20 n° 3 (July - September 2016) . - pp 503 – 527[article]Location K-anonymity in indoor spaces / Joon-Seok Kim in Geoinformatica, vol 20 n° 3 (July - September 2016)
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Titre : Location K-anonymity in indoor spaces Type de document : Article/Communication Auteurs : Joon-Seok Kim, Auteur ; Ki-Joune Li, Auteur Année de publication : 2016 Article en page(s) : pp 415–451 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géomatique
[Termes IGN] anonymisation
[Termes IGN] classification barycentrique
[Termes IGN] espace euclidien
[Termes IGN] graphe
[Termes IGN] positionnement en intérieur
[Termes IGN] protection de la vie privée
[Termes IGN] service fondé sur la positionRésumé : (auteur) With the expansion of wireless-communication infrastructure and the evolution of indoor positioning technologies, the demand for location-based services (LBS) has been increasing in indoor as well as outdoor spaces. However, we should consider a significant challenge regarding the location privacy for realizing indoor LBS. To avoid violations of location privacy, much research has been performed, and location K-anonymity has been intensively studied to blur a user location with a cloaking region involving at least K−1 locations of other persons. Owing to the differences between indoor and outdoor spaces, it is, however, difficult to apply this approach directly in an indoor space. First, the definition of the distance metric in indoor space is different from that in Euclidean and road-network spaces. Second, a bounding region, which is a general form of an anonymizing spatial region (ASR) in Euclidean space, does not respect the locality property in indoor space, where movement is constrained by building components. Therefore, we introduce the concept of indoor location K-anonymity in this paper. Then, we investigate the requirements of ASR in indoor spaces and propose novel methods to determine the ASR, considering hierarchical structures of the indoor space. While indoor ASRs are determined at the anonymizer, we also propose processing methods for r-range queries and k-nearest-neighbor queries at a location-based service provider. We validate our methods with experimental analysis of query-processing performance and resilience against attacks in indoor spaces. Numéro de notice : A2016-377 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1007/s10707-015-0241-y En ligne : http://dx.doi.org/10.1007/s10707-015-0241-y Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81144
in Geoinformatica > vol 20 n° 3 (July - September 2016) . - pp 415–451[article]Recursive orthogonal projection-based simplex growing algorithm / Hsiao-Chi Li in IEEE Transactions on geoscience and remote sensing, vol 54 n° 7 (July 2016)
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Titre : Recursive orthogonal projection-based simplex growing algorithm Type de document : Article/Communication Auteurs : Hsiao-Chi Li, Auteur ; Chein-I Chang, Auteur Année de publication : 2016 Article en page(s) : pp 3780 - 3793 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] algorithme du simplexe
[Termes IGN] filtre de Kalman
[Termes IGN] géophysique
[Termes IGN] image hyperspectrale
[Termes IGN] projection orthogonaleRésumé : (Auteur) The simplex growing algorithm (SGA) has been widely used for finding endmembers. It can be considered as a sequential version of the well-known endmember finding algorithm, N-finder algorithm (N-FINDR), which finds endmembers one at a time by growing simplexes. However, one of the major hurdles for N-FINDR and SGA is the calculation of simplex volume (SV) which poses a great challenge in designing any algorithm using SV as a criterion for finding endmembers. This paper develops an orthogonal projection (OP)-based SGA (OP-SGA) which essentially resolves this computational issue. It converts the issue of calculating SV to calculating the OP on previously found simplexes without computing matrix determinants. Most importantly, a recursive Kalman filter-like OP-SGA, to be called recursive OP-SGA (ROP-SGA), can be also derived to ease computation. By virtue of ROP-SGA, several advantages and benefits in computational savings and hardware implementation can be gained for which N-FINDR and SGA do not have. Numéro de notice : A2016-871 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2016.2527737 En ligne : http://dx.doi.org/10.1109/TGRS.2016.2527737 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83028
in IEEE Transactions on geoscience and remote sensing > vol 54 n° 7 (July 2016) . - pp 3780 - 3793[article]Robust high-quality interpolation of regions to moving regions / Florian Heinz in Geoinformatica, vol 20 n° 3 (July - September 2016)
[article]
Titre : Robust high-quality interpolation of regions to moving regions Type de document : Article/Communication Auteurs : Florian Heinz, Auteur ; Ralf Hartmut Güting, Auteur Année de publication : 2016 Article en page(s) : pp 385 – 413 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] analyse spatio-temporelle
[Termes IGN] base de données orientée objet
[Termes IGN] données spatiotemporelles
[Termes IGN] implémentation (informatique)
[Termes IGN] interpolation linéaire
[Termes IGN] méthode robuste
[Termes IGN] objet mobile
[Termes IGN] représentation du changementRésumé : (auteur) With the rise of moving object databases it is possible to store and process spatial and temporal data, for example geometrical structures together with the information about how these behave over intervals of time. For simple objects like moving points the spatiotemporal development is derived from the start and end position in space and time, which is then linearly interpolated. For moving regions, especially with changing shapes, it is more challenging to obtain the necessary data to represent them. An elegant and intuitive solution is to create an algorithm, which automatically interpolates the moving region from the start and end shape over a specified time interval. Two papers on this topic have been published in the past, each focussing on different aspects of this so-called Region Interpolation Problem. This paper tries to combine the advantages and improve these approaches to provide high-quality interpolations while maintaining robustness even in border cases. This results in the implementation of a library, which can be easily integrated into existing moving objects database systems, as for example the DBMS Secondo developed at the FernUniversität in Hagen. Numéro de notice : A2016-376 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1007/s10707-015-0240-z Date de publication en ligne : 12/11/2015 En ligne : https://doi.org/https://doi.org/10.1007/s10707-015-0240-z Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81143
in Geoinformatica > vol 20 n° 3 (July - September 2016) . - pp 385 – 413[article]Sparse and low-rank graph for discriminant analysis of hyperspectral imagery / Wei Li in IEEE Transactions on geoscience and remote sensing, vol 54 n° 7 (July 2016)PermalinkTask selection in spatial crowdsourcing from worker’s perspective / Dingxiong Deng in Geoinformatica, vol 20 n° 3 (July - September 2016)PermalinkSpectral band selection for urban material classification using hyperspectral libraries / Arnaud Le Bris in ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences, vol III-7 (July 2016)PermalinkFusion of hyperspectral and VHR multispectral image classifications in urban α–areas / Alexandre Hervieu in ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences, vol III-3 (July 2016)PermalinkIntegrating risk preferences in forest harvest scheduling / Kyle J. Eyvindson in Annals of Forest Science, vol 73 n° 2 (June 2016)PermalinkMesure de robustesse d'un réseau géodésique 3D : cas du réseau GPS de la ville d'Oran (Algérie) / Bachir Gourine in XYZ, n° 147 (juin - août 2016)PermalinkOptimization of observation plan based on the stochastic characteristics of the geodetic network / Wojciech Pachelski in Reports on geodesy and geoinformatics, vol 101 (June 2016)PermalinkVariants of the empirical interpolation method: symmetric formulation, choice of norms and rectangular extension / Fabien Casenave in Applied Mathematics Letters, vol 56 (June 2016)PermalinkVector attribute profiles for hyperspectral image classification / Erchan Aptoula in IEEE Transactions on geoscience and remote sensing, vol 54 n° 6 (June 2016)PermalinkReconstruction of the vertical electron density profile based on vertical TEC using the simulated annealing algorithm / Chunhua Jiang in Advances in space research, vol 57 n° 10 (May 2016)Permalink