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UL-Isomap based nonlinear dimensionality reduction for hyperspectral imagery classification / Weiwei Sun in ISPRS Journal of photogrammetry and remote sensing, vol 89 (March 2014)
[article]
Titre : UL-Isomap based nonlinear dimensionality reduction for hyperspectral imagery classification Type de document : Article/Communication Auteurs : Weiwei Sun, Auteur ; Avner Halevy, Auteur ; John J. Benedetto, Auteur ; Chun Liu, Auteur ; et al., Auteur Année de publication : 2014 Article en page(s) : pp 25 - 36 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] carte isoplèthe
[Termes IGN] classification barycentrique
[Termes IGN] graphe
[Termes IGN] image hyperspectrale
[Termes IGN] isoligne
[Termes IGN] point de repère
[Termes IGN] précision de la classification
[Termes IGN] réduction géométrique
[Termes IGN] valeur propreRésumé : (Auteur) The paper proposes an upgraded landmark-Isometric mapping (UL-Isomap) method to solve the two problems of landmark selection and computational complexity in dimensionality reduction using Landmark Isometric mapping (LIsomap) for hyperspectral imagery (HSI) classification. First, the vector quantization method is introduced to select proper landmarks for HSI data. The approach considers the variations in local density of pixels in the spectral space. It locates the unique landmarks representing the geometric structures of HSI data. Then, random projections are used to reduce the bands of HSI data. After that, the new method incorporates the Recursive Lanczos Bisection (RLB) algorithm to construct the fast approximate k-nearest neighbor graph. The RLB algorithm accompanied with random projections improves the speed of neighbor searching in UL-Isomap. After constructing the geodesic distance graph between landmarks and all pixels, the method uses a fast randomized low-rank approximate method to speed up the eigenvalue decomposition of the inner-product matrix in multidimensional scaling. Manifold coordinates of landmarks are then computed. Manifold coordinates of non-landmarks are computed through the pseudo inverse transformation of landmark coordinates. Five experiments on two different HSI datasets are run to test the new UL-Isomap method. Experimental results show that UL-Isomap surpasses LIsomap, both in the overall classification accuracy (OCA) and in computational speed, with a speed over 5 times faster. Moreover, the UL-Isomap method, when compared against the Isometric mapping (Isomap) method, obtains only slightly lower OCAs. Numéro de notice : A2014-122 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2013.12.003 En ligne : https://doi.org/10.1016/j.isprsjprs.2013.12.003 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=33027
in ISPRS Journal of photogrammetry and remote sensing > vol 89 (March 2014) . - pp 25 - 36[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-2014031 RAB Revue Centre de documentation En réserve L003 Disponible Dynamic positioning configuration and its first-order optimization / Shuqiang Xue in Journal of geodesy, vol 88 n° 2 (February 2014)
[article]
Titre : Dynamic positioning configuration and its first-order optimization Type de document : Article/Communication Auteurs : Shuqiang Xue, Auteur ; Yuanxi Yang, Auteur ; et al., Auteur Année de publication : 2014 Article en page(s) : pp 127 - 143 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] espace de Hilbert
[Termes IGN] optimisation (mathématiques)
[Termes IGN] positionnement par GPS
[Termes IGN] réseau de premier ordre
[Termes IGN] réseau géodésiqueRésumé : (Auteur) Traditional geodetic network optimization deals with static and discrete control points. The modern space geodetic network is, on the other hand, composed of moving control points in space (satellites) and on the Earth (ground stations). The network configuration composed of these facilities is essentially dynamic and continuous. Moreover, besides the position parameter which needs to be estimated, other geophysical information or signals can also be extracted from the continuous observations. The dynamic (continuous) configuration of the space network determines whether a particular frequency of signals can be identified by this system. In this paper, we employ the functional analysis and graph theory to study the dynamic configuration of space geodetic networks, and mainly focus on the optimal estimation of the position and clock-offset parameters. The principle of the D-optimization is introduced in the Hilbert space after the concept of the traditional discrete configuration is generalized from the finite space to the infinite space. It shows that the D-optimization developed in the discrete optimization is still valid in the dynamic configuration optimization, and this is attributed to the natural generalization of least squares from the Euclidean space to the Hilbert space. Then, we introduce the principle of D-optimality invariance under the combination operation and rotation operation, and propose some D-optimal simplex dynamic configurations: (1) (Semi) circular configuration in 2-dimensional space; (2) the D-optimal cone configuration and D-optimal helical configuration which is close to the GPS constellation in 3-dimensional space. The initial design of GPS constellation can be approximately treated as a combination of 24 D-optimal helixes by properly adjusting the ascending node of different satellites to realize a so-called Walker constellation. In the case of estimating the receiver clock-offset parameter, we show that the circular configuration, the symmetrical cone configuration and helical curve configuration are still D-optimal. It shows that the given total observation time determines the optimal frequency (repeatability) of moving known points and vice versa, and one way to improve the repeatability is to increase the rotational speed. Under the Newton’s law of motion, the frequency of satellite motion determines the orbital altitude. Furthermore, we study three kinds of complex dynamic configurations, one of which is the combination of D-optimal cone configurations and a so-called Walker constellation composed of D-optimal helical configuration, the other is the nested cone configuration composed of n cones, and the last is the nested helical configuration composed of n orbital planes. It shows that an effective way to achieve high coverage is to employ the configuration composed of a certain number of moving known points instead of the simplex configuration (such as D-optimal helical configuration), and one can use the D-optimal simplex solutions or D-optimal complex configurations in any combination to achieve powerful configurations with flexile coverage and flexile repeatability. Alternately, how to optimally generate and assess the discrete configurations sampled from the continuous one is discussed. The proposed configuration optimization framework has taken the well-known regular polygons (such as equilateral triangle and quadrangular) in two-dimensional space and regular polyhedrons (regular tetrahedron, cube, regular octahedron, regular icosahedron, or regular dodecahedron) into account. It shows that the conclusions made by the proposed technique are more general and no longer limited by different sampling schemes. By the conditional equation of D-optimal nested helical configuration, the relevance issues of GNSS constellation optimization are solved and some examples are performed by GPS constellation to verify the validation of the newly proposed optimization technique. The proposed technique is potentially helpful in maintenance and quadratic optimization of single GNSS of which the orbital inclination and the orbital altitude change under the precession, as well as in optimally nesting GNSSs to perform global homogeneous coverage of the Earth. Numéro de notice : A2014-139 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-013-0683-7 Date de publication en ligne : 03/12/2013 En ligne : https://doi.org/10.1007/s00190-013-0683-7 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=33044
in Journal of geodesy > vol 88 n° 2 (February 2014) . - pp 127 - 143[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 266-2014021 SL Revue Centre de documentation Revues en salle Disponible GDQM-PL13 – the new gravimetric quasigeoid model for Poland / Malgorzata Szelachowska in Geoinformation issues, vol 6 n° 1 (2014)
[article]
Titre : GDQM-PL13 – the new gravimetric quasigeoid model for Poland Type de document : Article/Communication Auteurs : Malgorzata Szelachowska, Auteur ; Jan Krynski, Auteur Année de publication : 2014 Article en page(s) : pp 5 - 19 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] anomalie de pesanteur
[Termes IGN] collocation par moindres carrés
[Termes IGN] données GNSS
[Termes IGN] géoïde gravimétrique
[Termes IGN] Pologne
[Termes IGN] quasi-géoïdeRésumé : (auteur) The new gravimetric quasigeoid model GDQM-PL13 for Poland was determined. The 1’×1’ mean Faye anomalies, deflections of the vertical for the territory of Poland, gravity anomalies from the neighbouring countries and the EGM2008 were used as input data. The remove-compute-restore (RCR) method and the least squares collocation approach with the planar logarithmic covariance function of gravity anomalies were applied. Height anomalies computed from the GDQM-PL13 have been compared with the corresponding ones obtained from GNSS/levelling data at the stations of the POLREF, EUVN and ASG-EUPOS networks and the precise GNSS/levelling control traverse. The new quasigeoid model was also compared with the gravimetric quasigeoid model GDQ08 developed in 2008 for the area of Poland, with the EGM2008, and with the most recent global geopotential model based on GOCE data. The results of the comparison were analysed and the accuracy of the GDQM-PL13 has been assessed and discussed. Numéro de notice : A2014-764 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans En ligne : http://www.igik.edu.pl/upload/File/wydawnictwa/GI6MSJK1.pdf Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76834
in Geoinformation issues > vol 6 n° 1 (2014) . - pp 5 - 19[article]Nonlinear unmixing of hyperspectral data using semi-nonnegative matrix factorization / Naoto Yokoya in IEEE Transactions on geoscience and remote sensing, vol 52 n° 2 (February 2014)
[article]
Titre : Nonlinear unmixing of hyperspectral data using semi-nonnegative matrix factorization Type de document : Article/Communication Auteurs : Naoto Yokoya, Auteur ; Jocelyn Chanussot, Auteur ; Akira Iwasaki, Auteur Année de publication : 2014 Article en page(s) : pp 1430 - 1437 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] analyse des mélanges spectraux
[Termes IGN] factorisation
[Termes IGN] image hyperspectrale
[Termes IGN] matrice
[Termes IGN] modèle non linéaireRésumé : (Auteur) Nonlinear spectral mixture models have recently received particular attention in hyperspectral image processing. In this paper, we present a novel optimization method of nonlinear unmixing based on a generalized bilinear model (GBM), which considers the second-order scattering of photons in a spectral mixture model. Semi-nonnegative matrix factorization (semi-NMF) is used for the optimization to process a whole image in matrix form. When endmember spectra are given, the optimization of abundance and interaction abundance fractions converge to a local optimum by alternating update rules with simple implementation. The proposed method is evaluated using synthetic datasets considering its robustness for the accuracy of endmember extraction and spectral complexity, and shows smaller errors in abundance fractions rather than conventional methods. GBM-based unmixing using semi-NMF is applied to the analysis of an airborne hyperspectral image taken over an agricultural field with many endmembers, and it visualizes the impact of a nonlinear interaction on abundance maps at reasonable computational cost. Numéro de notice : A2014-076 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2013.2245671 En ligne : https://doi.org/10.1109/TGRS.2013.2245671 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32981
in IEEE Transactions on geoscience and remote sensing > vol 52 n° 2 (February 2014) . - pp 1430 - 1437[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-2014021 RAB Revue Centre de documentation En réserve L003 Disponible Spatial patterns of historical growth changes in Norway spruce across western European mountains and the key effect of climate warming / Marie Charru in Trees, vol 28 n° 1 (February 2014)
[article]
Titre : Spatial patterns of historical growth changes in Norway spruce across western European mountains and the key effect of climate warming Type de document : Article/Communication Auteurs : Marie Charru, Auteur ; Ingrid Seynave, Auteur ; Jean-Christophe Hervé (1961-2017) , Auteur ; Jean-Daniel Bontemps , Auteur Année de publication : 2014 Article en page(s) : pp 205 - 221 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] Alpes (France)
[Termes IGN] analyse diachronique
[Termes IGN] changement climatique
[Termes IGN] croissance des arbres
[Termes IGN] inventaire forestier national (données France)
[Termes IGN] Jura, massif du
[Termes IGN] Massif central (France)
[Termes IGN] Picea abies
[Termes IGN] régression géographiquement pondérée
[Termes IGN] surface terrière
[Vedettes matières IGN] Végétation et changement climatiqueRésumé : (auteur) While forest growth changes have been observed in many places worldwide, their spatial variation and environmental origin remain poorly documented. Analysis of these historical changes in contrasted regional contexts, and their mapping over continuous environmental gradients, may help uncover their environmental causes. The approach was tested on Norway spruce (Picea abies) in three western European mountain contexts (Massif Central, Alps and Jura), using National Forest Inventory (NFI) data. We explored the environmental factors influencing stand basal area increment (BAI) in each context. We then estimated and compared mean regional changes in BAI and related these to the regional environmental limitations evidenced. Within each region, we further mapped local BAI trends using a geographically weighted regression (GWR) approach. In each region, local estimates of BAI changes were finally correlated to environmental indicators. We found an increase in BAI in the three regions over 1980–2005, greater in the Massif Central (+71 %) than in the Alps (+19 %) and the Jura Mountains (+21 %). Inter-regional differences in BAI changes suggested the release of a thermal constraint—found more important in the Massif Central—by the strong temperature increase over the period, and a limitation by water availability in the Jura and the Alps Mountains. Spatial patterns of BAI change revealed significant local variations in the Massif Central and the Alps. From the correlation analysis, these were again found consistent with the hypothesis of an enhancing effect of climate warming in these mountain ranges. They were also related to local soil nutritional status in the two regions, and negatively related to nitrogen deposition level in the Massif Central. As a main outcome, a strong context and spatial scale dependence of productivity changes is emphasized. In addition, the enhancing effect of climate warming on productivity is suggested, with local modulation by climatic and nutritional conditions. Numéro de notice : A2014-801 Affiliation des auteurs : LIF+Ext (2012-2019) Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00468-013-0943-4 Date de publication en ligne : 23/10/2013 En ligne : http://dx.doi.org/10.1007/s00468-013-0943-4 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83814
in Trees > vol 28 n° 1 (February 2014) . - pp 205 - 221[article]Statistical data fusion of multi-sensor AOD over the Continental United States / Sweta Jinnagara Puttaswamy in Geocarto international, vol 29 n° 1 - 2 (February - April 2014)PermalinkStructured sparse method for hyperspectral unmixing / Feiyun Zhu in ISPRS Journal of photogrammetry and remote sensing, vol 88 (February 2014)PermalinkActive learning of user’s preferences estimation towards a personalized 3D navigation of geo-referenced scenes / Christos Yiakoumettis in Geoinformatica, vol 18 n° 1 (January 2014)PermalinkAmélioration de la localisation 3D de données laser terrestre à l'aide de cartes 2D ou modèles 3D / Fabrice Monnier (2014)PermalinkAn algorithm for automatic detection of pole-like street furniture objects from Mobile Laser Scanner point clouds / C. Cabo in ISPRS Journal of photogrammetry and remote sensing, vol 87 (January 2014)PermalinkPermalinkComparing seven candidate mission configurations for temporal gravity field retrieval through full-scale numerical simulation / Basem Elsaka in Journal of geodesy, vol 88 n° 1 (January 2014)PermalinkGénération de modèles numériques de surface et détection de changements 3D à partir d'imagerie satellite stéréoscopique très haute résolution / Cyrielle Guerin (2014)PermalinkImagerie terrestre urbaine : vers une méthode physique d'estimation de la réflectance / Fabien Coubard (2014)PermalinkPermalinkPermalinkManifold harmonic transform and spatial relationships for partial 3D object retrieval / Nguyen-Vu Hoang (April 2014)PermalinkPrise en compte des déformations co- et post-sismiques pour la détermination d'un repère de référence / Daphné Lercier (2014)PermalinkRecherche des sous-réseaux d’antennes VLBI et de radio‐sources extra‐galactiques par algorithmes génétiques / Serge Nyoka (2014)PermalinkSémiologie graphique pour la représentation des dynamiques urbaines : Identification et modélisation de connaissances pour la conception de cartes diachroniques efficaces en superposition / Cécile Remy (2014)PermalinkSpatiotemporal filtering of regional GNSS network’s position time series with missing data using principle component analysis / Yunzhong Shen in Journal of geodesy, vol 88 n° 1 (January 2014)PermalinkA stochastic method for the generation of optimized building-layouts respecting urban regulation / Shuang He (oct 2014)PermalinkThe diffusion approximation for the linear Boltzmann equation with vanishing scattering coefficient / Claude Bardos in Communications in Mathematical Sciences, vol 13 n° 3 (2014)PermalinkToutes les mathématiques, nouveau programme / Luc Verschueren (2014)PermalinkUsing mobile laser scanning data for automated extraction of road markings / Haiyan Guan in ISPRS Journal of photogrammetry and remote sensing, vol 87 (January 2014)Permalink