Descripteur
Termes IGN > mathématiques > analyse numérique > optimisation (mathématiques)
optimisation (mathématiques)Synonyme(s)algorithme d'optimisation minimisationVoir aussi |
Documents disponibles dans cette catégorie (347)
Ajouter le résultat dans votre panier
Visionner les documents numériques
Affiner la recherche Interroger des sources externes
Etendre la recherche sur niveau(x) vers le bas
Global optimization of GNSS station reference networks / David Coulot in GPS solutions, vol 19 n° 4 (october 2015)
[article]
Titre : Global optimization of GNSS station reference networks Type de document : Article/Communication Auteurs : David Coulot , Auteur ; Paul Rebischung , Auteur ; Arnaud Pollet , Auteur ; Loïc Grondin, Auteur ; Guillaume Collot, Auteur Année de publication : 2015 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] algorithme génétique
[Termes IGN] International GNSS Service
[Termes IGN] optimisation (mathématiques)
[Termes IGN] réseau géodésique permanentRésumé : (auteur) The IGS08 reference network, adopted by the International GNSS Service (IGS) in 2011, and IGS08 core network are both of primary importance for the international GNSS community. They were empirically designed so as to fulfill several standards, such as the quality of the ITRF2008 positions and velocities of the involved stations, the reliability of the data they provide, and their global distribution. The present study shows that such global reference networks and well-distributed sub-networks can be objectively and rigorously designed with genetic algorithms (global optimization stochastic algorithms), on the basis of equivalent criteria. The IGS08-like reference networks and IGS08 core-like sub-networks provided by genetic algorithms respectively outperform the IGS08 and IGS08 core networks for the specific criteria in play. This opens the way to future essential applications: objective design of the next IGS reference and core networks, construction of dynamic core networks, and computation of user-specific global or regional GNSS reference networks. Numéro de notice : A2015-466 Affiliation des auteurs : LASTIG LAREG+Ext (2012-mi2018) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s10291-014-0416-2 Date de publication en ligne : 14/10/2014 En ligne : https://doi.org/10.1007/s10291-014-0416-2 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=77154
in GPS solutions > vol 19 n° 4 (october 2015)[article]Stochastic geometrical model and Monte Carlo optimization methods for building reconstruction from InSAR data / Yue Zhang in ISPRS Journal of photogrammetry and remote sensing, vol 108 (October 2015)
[article]
Titre : Stochastic geometrical model and Monte Carlo optimization methods for building reconstruction from InSAR data Type de document : Article/Communication Auteurs : Yue Zhang, Auteur ; Xuan Sun, Auteur ; Antje Thiele, Auteur ; Stefan Hinz, Auteur Année de publication : 2015 Article en page(s) : pp 49 – 61 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] image radar moirée
[Termes IGN] image TanDEM-X
[Termes IGN] interféromètrie par radar à antenne synthétique
[Termes IGN] méthode de Monte-Carlo
[Termes IGN] modèle stochastique
[Termes IGN] optimisation (mathématiques)
[Termes IGN] reconstruction 3D du bâtiRésumé : (auteur) Synthetic aperture radar (SAR) systems, such as TanDEM-X, TerraSAR-X and Cosmo-SkyMed, acquire imagery with high spatial resolution (HR), making it possible to observe objects in urban areas with high detail. In this paper, we propose a new top-down framework for three-dimensional (3D) building reconstruction from HR interferometric SAR (InSAR) data. Unlike most methods proposed before, we adopt a generative model and utilize the reconstruction process by maximizing a posteriori estimation (MAP) through Monte Carlo methods. The reason for this strategy refers to the fact that the noisiness of SAR images calls for a thorough prior model to better cope with the inherent amplitude and phase fluctuations.
In the reconstruction process, according to the radar configuration and the building geometry, a 3D building hypothesis is mapped to the SAR image plane and decomposed to feature regions such as layover, corner line, and shadow. Then, the statistical properties of intensity, interferometric phase and coherence of each region are explored respectively, and are included as region terms. Roofs are not directly considered as they are mixed with wall into layover area in most cases. When estimating the similarity between the building hypothesis and the real data, the prior, the region term, together with the edge term related to the contours of layover and corner line, are taken into consideration. In the optimization step, in order to achieve convergent reconstruction outputs and get rid of local extrema, special transition kernels are designed. The proposed framework is evaluated on the TanDEM-X dataset and performs well for buildings reconstruction.Numéro de notice : A2015-851 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2015.06.004 En ligne : http://dx.doi.org/10.1016/j.isprsjprs.2015.06.004 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79221
in ISPRS Journal of photogrammetry and remote sensing > vol 108 (October 2015) . - pp 49 – 61[article]Minimum volume simplex analysis: A fast algorithm for linear hyperspectral unmixing / Jun Li in IEEE Transactions on geoscience and remote sensing, vol 53 n° 9 (September 2015)
[article]
Titre : Minimum volume simplex analysis: A fast algorithm for linear hyperspectral unmixing Type de document : Article/Communication Auteurs : Jun Li, Auteur ; Alexander Agathos, Auteur ; Daniela Zaharie, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 5067 - 5082 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] algorithme du simplexe
[Termes IGN] analyse linéaire des mélanges spectraux
[Termes IGN] décomposition du pixel
[Termes IGN] image hyperspectrale
[Termes IGN] implémentation (informatique)Résumé : (Auteur) Linear spectral unmixing aims at estimating the number of pure spectral substances, also called endmembers, their spectral signatures, and their abundance fractions in remotely sensed hyperspectral images. This paper describes a method for unsupervised hyperspectral unmixing called minimum volume simplex analysis (MVSA) and introduces a new computationally efficient implementation. MVSA approaches hyperspectral unmixing by fitting a minimum volume simplex to the hyperspectral data, constraining the abundance fractions to belong to the probability simplex. The resulting optimization problem, which is computationally complex, is solved in this paper by implementing a sequence of quadratically constrained subproblems using the interior point method, which is particularly effective from the computational viewpoint. The proposed implementation (available online: www.lx.it.pt/%7ejun/DemoMVSA.zip) is shown to exhibit state-of-the-art performance not only in terms of unmixing accuracy, particularly in nonpure pixel scenarios, but also in terms of computational performance. Our experiments have been conducted using both synthetic and real data sets. An important assumption of MVSA is that pure pixels may not be present in the hyperspectral data, thus addressing a common situation in real scenarios which are often dominated by highly mixed pixels. In our experiments, we observe that MVSA yields competitive performance when compared with other available algorithms that work under the nonpure pixel regime. Our results also demonstrate that MVSA is well suited to problems involving a high number of endmembers (i.e., complex scenes) and also for problems involving a high number of pixels (i.e., large scenes). Numéro de notice : A2015-528 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2015.2417162 Date de publication en ligne : 21/04/2015 En ligne : https://doi.org/10.1109/TGRS.2015.2417162 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=77556
in IEEE Transactions on geoscience and remote sensing > vol 53 n° 9 (September 2015) . - pp 5067 - 5082[article]Réservation
Réserver ce documentExemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 065-2015091 SL Revue Centre de documentation Revues en salle Disponible Routes visualization: Automated placement of multiple route symbols along a physical network infrastructure / Jules Teulade-Denantes in Journal of Spatial Information Science (JoSIS), n° 11 (September 2015)
[article]
Titre : Routes visualization: Automated placement of multiple route symbols along a physical network infrastructure Type de document : Article/Communication Auteurs : Jules Teulade-Denantes, Auteur ; Adrien Maudet , Auteur ; Cécile Duchêne , Auteur Année de publication : 2015 Article en page(s) : 53--79 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] algorithme du recuit simulé
[Termes IGN] carte routière
[Termes IGN] optimisation (mathématiques)
[Termes IGN] placement automatique des signes conventionnels
[Termes IGN] programmation par contraintes
[Termes IGN] réseau routier
[Termes IGN] sentier
[Vedettes matières IGN] GénéralisationMots-clés libres : automated cartography route maps symbol placement constraint formulation constraint optimization problem simulated annealing Résumé : (auteur) This paper tackles the representation of routes carried by a physical network infrastructure on a map. In particular, the paper examines the case where each route is represented by a separate colored linear symbol offset from the physical network segments and from other routes—as on public transit maps with bus routes offset from roads. In this study, the objective is to automate the placement of such route symbols while maximizing their legibility, especially at junctions. The problem is modeled as a constraint optimization problem. Legibility criteria are identified and formalized as constraints to optimize, while focusing on the case of hiking routes in a physical network composed of roads and pedestrian paths. Two solving methods are tested, based on backtracking and simulated annealing meta-heuristics respectively. Encouraging results obtained on real data are presented and discussed. Numéro de notice : A2015--057 Affiliation des auteurs : LASTIG COGIT (2012-2019) Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.5311/JOSIS.2015.11.230 Date de publication en ligne : 17/09/2015 En ligne : http://dx.doi.org/10.5311/JOSIS.2015.11.230 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83281
in Journal of Spatial Information Science (JoSIS) > n° 11 (September 2015) . - 53--79[article]Documents numériques
en open access
Routes visualizationAdobe Acrobat PDF Short-term surface deformation on the Northern Hayward Fault, CA, and nearby landslides using polarimetric SAR interferometry (PolInSAR) / Samira Alipour in Pure and applied geophysics, vol 172 n° 8 (August 2015)
[article]
Titre : Short-term surface deformation on the Northern Hayward Fault, CA, and nearby landslides using polarimetric SAR interferometry (PolInSAR) Type de document : Article/Communication Auteurs : Samira Alipour, Auteur ; Christy F. Tiampo, Auteur ; Sergey V. Samsonov, Auteur ; Pablo J. González, Auteur Année de publication : 2015 Article en page(s) : pp 2179 - 2193 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] Californie (Etats-Unis)
[Termes IGN] faille géologique
[Termes IGN] image Radarsat
[Termes IGN] optimisation (mathématiques)
[Termes IGN] polarimétrie radar
[Termes IGN] risque naturelRésumé : (auteur) In this study, we analyze 25 RADARSAT-2 images from ascending and descending geometries to study the creep rate on the Hayward fault and landslide motions near Berkeley, CA. We applied a coherence optimization technique from polarimetric synthetic aperture radar interferometry (PolInSAR) to increase the accuracy of the measurements. We resolve 3–5 mm/year of motion along the Hayward fault, in agreement with earlier creep estimates. We identify a potential motion on secondary fault, northeast and parallel to the Hayward fault, which is creeping at a lower rate of ~1.5 mm/year. In addition, we identify a number of landslides along the hills east of the fault that agree with earlier results from advanced interferometric synthetic aperture radar (SAR) analysis and field investigations. We investigate four particular slope instabilities, one of which was marked as moderately active, and three as highly active, by earlier field investigations. The resolved along-hill slope displacement is estimated at ~23 mm/year. Our results demonstrate that PolInSAR is an effective method to increase the interferometric coherence and provide improved resolution of deformation features associated with natural hazards. Numéro de notice : A2015-492 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1007/s00024-013-0747-x Date de publication en ligne : 10/12/2013 En ligne : https://doi.org/10.1007/s00024-013-0747-x Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=77287
in Pure and applied geophysics > vol 172 n° 8 (August 2015) . - pp 2179 - 2193[article]Hyperspectral and multispectral image fusion based on a sparse representation / Qi Wei in IEEE Transactions on geoscience and remote sensing, vol 53 n° 7 (July 2015)PermalinkAdaptive relative motion representation of space–time trajectories / Antoni B. Moore in Cartographic journal (the), Vol 52 n° 2 (May 2015)PermalinkA technique for simultaneous visualization and segmentation of hyperspectral data / Abhimitra Meka in IEEE Transactions on geoscience and remote sensing, vol 53 n° 4 (April 2015)PermalinkCollaborative representation for hyperspectral anomaly detection / Wei Li in IEEE Transactions on geoscience and remote sensing, vol 53 n° 3 (March 2015)PermalinkProgressive band processing of constrained energy minimization for subpixel detection / Chein-I Chang in IEEE Transactions on geoscience and remote sensing, vol 53 n° 3 (March 2015)PermalinkMultibaseline polarimetric synthetic aperture radar tomography of forested areas using wavelet-based distribution compressive sensing / Lei Liang in Journal of applied remote sensing, vol 9 (2015)PermalinkAlgorithms for vision-based path following along previously taught paths / Deon George Sabatta (2015)PermalinkAutomatic spatial–spectral feature selection for hyperspectral image via discriminative sparse multimodal learning / Qian Zhang in IEEE Transactions on geoscience and remote sensing, vol 53 n° 1 (January 2015)PermalinkPermalinkOptimisation de la configuration d’un instrument superspectral aéroporté pour la classification : application au milieu urbain / Arnaud Le Bris (2015)Permalink